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v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  libata-sff.c - helper library for PCI IDE BMDMA
   4 *
   5 *  Copyright 2003-2006 Red Hat, Inc.  All rights reserved.
   6 *  Copyright 2003-2006 Jeff Garzik
   7 *
   8 *  libata documentation is available via 'make {ps|pdf}docs',
   9 *  as Documentation/driver-api/libata.rst
  10 *
  11 *  Hardware documentation available from http://www.t13.org/ and
  12 *  http://www.sata-io.org/
  13 */
  14
  15#include <linux/kernel.h>
  16#include <linux/gfp.h>
  17#include <linux/pci.h>
  18#include <linux/module.h>
  19#include <linux/libata.h>
  20#include <linux/highmem.h>
  21#include <trace/events/libata.h>
  22#include "libata.h"
  23
  24static struct workqueue_struct *ata_sff_wq;
  25
  26const struct ata_port_operations ata_sff_port_ops = {
  27	.inherits		= &ata_base_port_ops,
  28
 
  29	.qc_issue		= ata_sff_qc_issue,
  30	.qc_fill_rtf		= ata_sff_qc_fill_rtf,
  31
  32	.freeze			= ata_sff_freeze,
  33	.thaw			= ata_sff_thaw,
  34	.prereset		= ata_sff_prereset,
  35	.softreset		= ata_sff_softreset,
  36	.hardreset		= sata_sff_hardreset,
  37	.postreset		= ata_sff_postreset,
  38	.error_handler		= ata_sff_error_handler,
  39
  40	.sff_dev_select		= ata_sff_dev_select,
  41	.sff_check_status	= ata_sff_check_status,
  42	.sff_tf_load		= ata_sff_tf_load,
  43	.sff_tf_read		= ata_sff_tf_read,
  44	.sff_exec_command	= ata_sff_exec_command,
  45	.sff_data_xfer		= ata_sff_data_xfer,
  46	.sff_drain_fifo		= ata_sff_drain_fifo,
  47
  48	.lost_interrupt		= ata_sff_lost_interrupt,
  49};
  50EXPORT_SYMBOL_GPL(ata_sff_port_ops);
  51
  52/**
  53 *	ata_sff_check_status - Read device status reg & clear interrupt
  54 *	@ap: port where the device is
  55 *
  56 *	Reads ATA taskfile status register for currently-selected device
  57 *	and return its value. This also clears pending interrupts
  58 *      from this device
  59 *
  60 *	LOCKING:
  61 *	Inherited from caller.
  62 */
  63u8 ata_sff_check_status(struct ata_port *ap)
  64{
  65	return ioread8(ap->ioaddr.status_addr);
  66}
  67EXPORT_SYMBOL_GPL(ata_sff_check_status);
  68
  69/**
  70 *	ata_sff_altstatus - Read device alternate status reg
  71 *	@ap: port where the device is
  72 *	@status: pointer to a status value
  73 *
  74 *	Reads ATA alternate status register for currently-selected device
  75 *	and return its value.
  76 *
  77 *	RETURN:
  78 *	true if the register exists, false if not.
  79 *
  80 *	LOCKING:
  81 *	Inherited from caller.
  82 */
  83static bool ata_sff_altstatus(struct ata_port *ap, u8 *status)
  84{
  85	u8 tmp;
  86
  87	if (ap->ops->sff_check_altstatus) {
  88		tmp = ap->ops->sff_check_altstatus(ap);
  89		goto read;
  90	}
  91	if (ap->ioaddr.altstatus_addr) {
  92		tmp = ioread8(ap->ioaddr.altstatus_addr);
  93		goto read;
  94	}
  95	return false;
  96
  97read:
  98	if (status)
  99		*status = tmp;
 100	return true;
 101}
 102
 103/**
 104 *	ata_sff_irq_status - Check if the device is busy
 105 *	@ap: port where the device is
 106 *
 107 *	Determine if the port is currently busy. Uses altstatus
 108 *	if available in order to avoid clearing shared IRQ status
 109 *	when finding an IRQ source. Non ctl capable devices don't
 110 *	share interrupt lines fortunately for us.
 111 *
 112 *	LOCKING:
 113 *	Inherited from caller.
 114 */
 115static u8 ata_sff_irq_status(struct ata_port *ap)
 116{
 117	u8 status;
 118
 119	/* Not us: We are busy */
 120	if (ata_sff_altstatus(ap, &status) && (status & ATA_BUSY))
 121		return status;
 122	/* Clear INTRQ latch */
 123	status = ap->ops->sff_check_status(ap);
 124	return status;
 125}
 126
 127/**
 128 *	ata_sff_sync - Flush writes
 129 *	@ap: Port to wait for.
 130 *
 131 *	CAUTION:
 132 *	If we have an mmio device with no ctl and no altstatus
 133 *	method this will fail. No such devices are known to exist.
 134 *
 135 *	LOCKING:
 136 *	Inherited from caller.
 137 */
 138
 139static void ata_sff_sync(struct ata_port *ap)
 140{
 141	ata_sff_altstatus(ap, NULL);
 142}
 143
 144/**
 145 *	ata_sff_pause		-	Flush writes and wait 400nS
 146 *	@ap: Port to pause for.
 147 *
 148 *	CAUTION:
 149 *	If we have an mmio device with no ctl and no altstatus
 150 *	method this will fail. No such devices are known to exist.
 151 *
 152 *	LOCKING:
 153 *	Inherited from caller.
 154 */
 155
 156void ata_sff_pause(struct ata_port *ap)
 157{
 158	ata_sff_sync(ap);
 159	ndelay(400);
 160}
 161EXPORT_SYMBOL_GPL(ata_sff_pause);
 162
 163/**
 164 *	ata_sff_dma_pause	-	Pause before commencing DMA
 165 *	@ap: Port to pause for.
 166 *
 167 *	Perform I/O fencing and ensure sufficient cycle delays occur
 168 *	for the HDMA1:0 transition
 169 */
 170
 171void ata_sff_dma_pause(struct ata_port *ap)
 172{
 173	/*
 174	 * An altstatus read will cause the needed delay without
 175	 * messing up the IRQ status
 176	 */
 177	if (ata_sff_altstatus(ap, NULL))
 178		return;
 179	/* There are no DMA controllers without ctl. BUG here to ensure
 180	   we never violate the HDMA1:0 transition timing and risk
 181	   corruption. */
 182	BUG();
 183}
 184EXPORT_SYMBOL_GPL(ata_sff_dma_pause);
 185
 186static int ata_sff_check_ready(struct ata_link *link)
 187{
 188	u8 status = link->ap->ops->sff_check_status(link->ap);
 189
 190	return ata_check_ready(status);
 191}
 192
 193/**
 194 *	ata_sff_wait_ready - sleep until BSY clears, or timeout
 195 *	@link: SFF link to wait ready status for
 196 *	@deadline: deadline jiffies for the operation
 197 *
 198 *	Sleep until ATA Status register bit BSY clears, or timeout
 199 *	occurs.
 200 *
 201 *	LOCKING:
 202 *	Kernel thread context (may sleep).
 203 *
 204 *	RETURNS:
 205 *	0 on success, -errno otherwise.
 206 */
 207int ata_sff_wait_ready(struct ata_link *link, unsigned long deadline)
 208{
 209	return ata_wait_ready(link, deadline, ata_sff_check_ready);
 210}
 211EXPORT_SYMBOL_GPL(ata_sff_wait_ready);
 212
 213/**
 214 *	ata_sff_set_devctl - Write device control reg
 215 *	@ap: port where the device is
 216 *	@ctl: value to write
 217 *
 218 *	Writes ATA device control register.
 219 *
 220 *	RETURN:
 221 *	true if the register exists, false if not.
 222 *
 223 *	LOCKING:
 224 *	Inherited from caller.
 225 */
 226static bool ata_sff_set_devctl(struct ata_port *ap, u8 ctl)
 227{
 228	if (ap->ops->sff_set_devctl) {
 229		ap->ops->sff_set_devctl(ap, ctl);
 230		return true;
 231	}
 232	if (ap->ioaddr.ctl_addr) {
 233		iowrite8(ctl, ap->ioaddr.ctl_addr);
 234		return true;
 235	}
 236
 237	return false;
 238}
 239
 240/**
 241 *	ata_sff_dev_select - Select device 0/1 on ATA bus
 242 *	@ap: ATA channel to manipulate
 243 *	@device: ATA device (numbered from zero) to select
 244 *
 245 *	Use the method defined in the ATA specification to
 246 *	make either device 0, or device 1, active on the
 247 *	ATA channel.  Works with both PIO and MMIO.
 248 *
 249 *	May be used as the dev_select() entry in ata_port_operations.
 250 *
 251 *	LOCKING:
 252 *	caller.
 253 */
 254void ata_sff_dev_select(struct ata_port *ap, unsigned int device)
 255{
 256	u8 tmp;
 257
 258	if (device == 0)
 259		tmp = ATA_DEVICE_OBS;
 260	else
 261		tmp = ATA_DEVICE_OBS | ATA_DEV1;
 262
 263	iowrite8(tmp, ap->ioaddr.device_addr);
 264	ata_sff_pause(ap);	/* needed; also flushes, for mmio */
 265}
 266EXPORT_SYMBOL_GPL(ata_sff_dev_select);
 267
 268/**
 269 *	ata_dev_select - Select device 0/1 on ATA bus
 270 *	@ap: ATA channel to manipulate
 271 *	@device: ATA device (numbered from zero) to select
 272 *	@wait: non-zero to wait for Status register BSY bit to clear
 273 *	@can_sleep: non-zero if context allows sleeping
 274 *
 275 *	Use the method defined in the ATA specification to
 276 *	make either device 0, or device 1, active on the
 277 *	ATA channel.
 278 *
 279 *	This is a high-level version of ata_sff_dev_select(), which
 280 *	additionally provides the services of inserting the proper
 281 *	pauses and status polling, where needed.
 282 *
 283 *	LOCKING:
 284 *	caller.
 285 */
 286static void ata_dev_select(struct ata_port *ap, unsigned int device,
 287			   unsigned int wait, unsigned int can_sleep)
 288{
 289	if (wait)
 290		ata_wait_idle(ap);
 291
 292	ap->ops->sff_dev_select(ap, device);
 293
 294	if (wait) {
 295		if (can_sleep && ap->link.device[device].class == ATA_DEV_ATAPI)
 296			ata_msleep(ap, 150);
 297		ata_wait_idle(ap);
 298	}
 299}
 300
 301/**
 302 *	ata_sff_irq_on - Enable interrupts on a port.
 303 *	@ap: Port on which interrupts are enabled.
 304 *
 305 *	Enable interrupts on a legacy IDE device using MMIO or PIO,
 306 *	wait for idle, clear any pending interrupts.
 307 *
 308 *	Note: may NOT be used as the sff_irq_on() entry in
 309 *	ata_port_operations.
 310 *
 311 *	LOCKING:
 312 *	Inherited from caller.
 313 */
 314void ata_sff_irq_on(struct ata_port *ap)
 315{
 316	if (ap->ops->sff_irq_on) {
 317		ap->ops->sff_irq_on(ap);
 318		return;
 319	}
 320
 321	ap->ctl &= ~ATA_NIEN;
 322	ap->last_ctl = ap->ctl;
 323
 324	ata_sff_set_devctl(ap, ap->ctl);
 325	ata_wait_idle(ap);
 326
 327	if (ap->ops->sff_irq_clear)
 328		ap->ops->sff_irq_clear(ap);
 329}
 330EXPORT_SYMBOL_GPL(ata_sff_irq_on);
 331
 332/**
 333 *	ata_sff_tf_load - send taskfile registers to host controller
 334 *	@ap: Port to which output is sent
 335 *	@tf: ATA taskfile register set
 336 *
 337 *	Outputs ATA taskfile to standard ATA host controller.
 338 *
 339 *	LOCKING:
 340 *	Inherited from caller.
 341 */
 342void ata_sff_tf_load(struct ata_port *ap, const struct ata_taskfile *tf)
 343{
 344	struct ata_ioports *ioaddr = &ap->ioaddr;
 345	unsigned int is_addr = tf->flags & ATA_TFLAG_ISADDR;
 346
 347	if (tf->ctl != ap->last_ctl) {
 348		if (ioaddr->ctl_addr)
 349			iowrite8(tf->ctl, ioaddr->ctl_addr);
 350		ap->last_ctl = tf->ctl;
 351		ata_wait_idle(ap);
 352	}
 353
 354	if (is_addr && (tf->flags & ATA_TFLAG_LBA48)) {
 355		WARN_ON_ONCE(!ioaddr->ctl_addr);
 356		iowrite8(tf->hob_feature, ioaddr->feature_addr);
 357		iowrite8(tf->hob_nsect, ioaddr->nsect_addr);
 358		iowrite8(tf->hob_lbal, ioaddr->lbal_addr);
 359		iowrite8(tf->hob_lbam, ioaddr->lbam_addr);
 360		iowrite8(tf->hob_lbah, ioaddr->lbah_addr);
 361	}
 362
 363	if (is_addr) {
 364		iowrite8(tf->feature, ioaddr->feature_addr);
 365		iowrite8(tf->nsect, ioaddr->nsect_addr);
 366		iowrite8(tf->lbal, ioaddr->lbal_addr);
 367		iowrite8(tf->lbam, ioaddr->lbam_addr);
 368		iowrite8(tf->lbah, ioaddr->lbah_addr);
 369	}
 370
 371	if (tf->flags & ATA_TFLAG_DEVICE)
 372		iowrite8(tf->device, ioaddr->device_addr);
 373
 374	ata_wait_idle(ap);
 375}
 376EXPORT_SYMBOL_GPL(ata_sff_tf_load);
 377
 378/**
 379 *	ata_sff_tf_read - input device's ATA taskfile shadow registers
 380 *	@ap: Port from which input is read
 381 *	@tf: ATA taskfile register set for storing input
 382 *
 383 *	Reads ATA taskfile registers for currently-selected device
 384 *	into @tf. Assumes the device has a fully SFF compliant task file
 385 *	layout and behaviour. If you device does not (eg has a different
 386 *	status method) then you will need to provide a replacement tf_read
 387 *
 388 *	LOCKING:
 389 *	Inherited from caller.
 390 */
 391void ata_sff_tf_read(struct ata_port *ap, struct ata_taskfile *tf)
 392{
 393	struct ata_ioports *ioaddr = &ap->ioaddr;
 394
 395	tf->status = ata_sff_check_status(ap);
 396	tf->error = ioread8(ioaddr->error_addr);
 397	tf->nsect = ioread8(ioaddr->nsect_addr);
 398	tf->lbal = ioread8(ioaddr->lbal_addr);
 399	tf->lbam = ioread8(ioaddr->lbam_addr);
 400	tf->lbah = ioread8(ioaddr->lbah_addr);
 401	tf->device = ioread8(ioaddr->device_addr);
 402
 403	if (tf->flags & ATA_TFLAG_LBA48) {
 404		if (likely(ioaddr->ctl_addr)) {
 405			iowrite8(tf->ctl | ATA_HOB, ioaddr->ctl_addr);
 406			tf->hob_feature = ioread8(ioaddr->error_addr);
 407			tf->hob_nsect = ioread8(ioaddr->nsect_addr);
 408			tf->hob_lbal = ioread8(ioaddr->lbal_addr);
 409			tf->hob_lbam = ioread8(ioaddr->lbam_addr);
 410			tf->hob_lbah = ioread8(ioaddr->lbah_addr);
 411			iowrite8(tf->ctl, ioaddr->ctl_addr);
 412			ap->last_ctl = tf->ctl;
 413		} else
 414			WARN_ON_ONCE(1);
 415	}
 416}
 417EXPORT_SYMBOL_GPL(ata_sff_tf_read);
 418
 419/**
 420 *	ata_sff_exec_command - issue ATA command to host controller
 421 *	@ap: port to which command is being issued
 422 *	@tf: ATA taskfile register set
 423 *
 424 *	Issues ATA command, with proper synchronization with interrupt
 425 *	handler / other threads.
 426 *
 427 *	LOCKING:
 428 *	spin_lock_irqsave(host lock)
 429 */
 430void ata_sff_exec_command(struct ata_port *ap, const struct ata_taskfile *tf)
 431{
 432	iowrite8(tf->command, ap->ioaddr.command_addr);
 433	ata_sff_pause(ap);
 434}
 435EXPORT_SYMBOL_GPL(ata_sff_exec_command);
 436
 437/**
 438 *	ata_tf_to_host - issue ATA taskfile to host controller
 439 *	@ap: port to which command is being issued
 440 *	@tf: ATA taskfile register set
 441 *	@tag: tag of the associated command
 442 *
 443 *	Issues ATA taskfile register set to ATA host controller,
 444 *	with proper synchronization with interrupt handler and
 445 *	other threads.
 446 *
 447 *	LOCKING:
 448 *	spin_lock_irqsave(host lock)
 449 */
 450static inline void ata_tf_to_host(struct ata_port *ap,
 451				  const struct ata_taskfile *tf,
 452				  unsigned int tag)
 453{
 454	trace_ata_tf_load(ap, tf);
 455	ap->ops->sff_tf_load(ap, tf);
 456	trace_ata_exec_command(ap, tf, tag);
 457	ap->ops->sff_exec_command(ap, tf);
 458}
 459
 460/**
 461 *	ata_sff_data_xfer - Transfer data by PIO
 462 *	@qc: queued command
 463 *	@buf: data buffer
 464 *	@buflen: buffer length
 465 *	@rw: read/write
 466 *
 467 *	Transfer data from/to the device data register by PIO.
 468 *
 469 *	LOCKING:
 470 *	Inherited from caller.
 471 *
 472 *	RETURNS:
 473 *	Bytes consumed.
 474 */
 475unsigned int ata_sff_data_xfer(struct ata_queued_cmd *qc, unsigned char *buf,
 476			       unsigned int buflen, int rw)
 477{
 478	struct ata_port *ap = qc->dev->link->ap;
 479	void __iomem *data_addr = ap->ioaddr.data_addr;
 480	unsigned int words = buflen >> 1;
 481
 482	/* Transfer multiple of 2 bytes */
 483	if (rw == READ)
 484		ioread16_rep(data_addr, buf, words);
 485	else
 486		iowrite16_rep(data_addr, buf, words);
 487
 488	/* Transfer trailing byte, if any. */
 489	if (unlikely(buflen & 0x01)) {
 490		unsigned char pad[2] = { };
 491
 492		/* Point buf to the tail of buffer */
 493		buf += buflen - 1;
 494
 495		/*
 496		 * Use io*16_rep() accessors here as well to avoid pointlessly
 497		 * swapping bytes to and from on the big endian machines...
 498		 */
 499		if (rw == READ) {
 500			ioread16_rep(data_addr, pad, 1);
 501			*buf = pad[0];
 502		} else {
 503			pad[0] = *buf;
 504			iowrite16_rep(data_addr, pad, 1);
 505		}
 506		words++;
 507	}
 508
 509	return words << 1;
 510}
 511EXPORT_SYMBOL_GPL(ata_sff_data_xfer);
 512
 513/**
 514 *	ata_sff_data_xfer32 - Transfer data by PIO
 515 *	@qc: queued command
 516 *	@buf: data buffer
 517 *	@buflen: buffer length
 518 *	@rw: read/write
 519 *
 520 *	Transfer data from/to the device data register by PIO using 32bit
 521 *	I/O operations.
 522 *
 523 *	LOCKING:
 524 *	Inherited from caller.
 525 *
 526 *	RETURNS:
 527 *	Bytes consumed.
 528 */
 529
 530unsigned int ata_sff_data_xfer32(struct ata_queued_cmd *qc, unsigned char *buf,
 531			       unsigned int buflen, int rw)
 532{
 533	struct ata_device *dev = qc->dev;
 534	struct ata_port *ap = dev->link->ap;
 535	void __iomem *data_addr = ap->ioaddr.data_addr;
 536	unsigned int words = buflen >> 2;
 537	int slop = buflen & 3;
 538
 539	if (!(ap->pflags & ATA_PFLAG_PIO32))
 540		return ata_sff_data_xfer(qc, buf, buflen, rw);
 541
 542	/* Transfer multiple of 4 bytes */
 543	if (rw == READ)
 544		ioread32_rep(data_addr, buf, words);
 545	else
 546		iowrite32_rep(data_addr, buf, words);
 547
 548	/* Transfer trailing bytes, if any */
 549	if (unlikely(slop)) {
 550		unsigned char pad[4] = { };
 551
 552		/* Point buf to the tail of buffer */
 553		buf += buflen - slop;
 554
 555		/*
 556		 * Use io*_rep() accessors here as well to avoid pointlessly
 557		 * swapping bytes to and from on the big endian machines...
 558		 */
 559		if (rw == READ) {
 560			if (slop < 3)
 561				ioread16_rep(data_addr, pad, 1);
 562			else
 563				ioread32_rep(data_addr, pad, 1);
 564			memcpy(buf, pad, slop);
 565		} else {
 566			memcpy(pad, buf, slop);
 567			if (slop < 3)
 568				iowrite16_rep(data_addr, pad, 1);
 569			else
 570				iowrite32_rep(data_addr, pad, 1);
 571		}
 572	}
 573	return (buflen + 1) & ~1;
 574}
 575EXPORT_SYMBOL_GPL(ata_sff_data_xfer32);
 576
 577static void ata_pio_xfer(struct ata_queued_cmd *qc, struct page *page,
 578		unsigned int offset, size_t xfer_size)
 579{
 580	bool do_write = (qc->tf.flags & ATA_TFLAG_WRITE);
 581	unsigned char *buf;
 582
 583	buf = kmap_atomic(page);
 584	qc->ap->ops->sff_data_xfer(qc, buf + offset, xfer_size, do_write);
 585	kunmap_atomic(buf);
 586
 587	if (!do_write && !PageSlab(page))
 588		flush_dcache_page(page);
 589}
 590
 591/**
 592 *	ata_pio_sector - Transfer a sector of data.
 593 *	@qc: Command on going
 594 *
 595 *	Transfer qc->sect_size bytes of data from/to the ATA device.
 596 *
 597 *	LOCKING:
 598 *	Inherited from caller.
 599 */
 600static void ata_pio_sector(struct ata_queued_cmd *qc)
 601{
 602	struct ata_port *ap = qc->ap;
 603	struct page *page;
 604	unsigned int offset, count;
 605
 606	if (!qc->cursg) {
 607		qc->curbytes = qc->nbytes;
 608		return;
 609	}
 610	if (qc->curbytes == qc->nbytes - qc->sect_size)
 611		ap->hsm_task_state = HSM_ST_LAST;
 612
 613	page = sg_page(qc->cursg);
 614	offset = qc->cursg->offset + qc->cursg_ofs;
 615
 616	/* get the current page and offset */
 617	page = nth_page(page, (offset >> PAGE_SHIFT));
 618	offset %= PAGE_SIZE;
 619
 620	/* don't overrun current sg */
 621	count = min(qc->cursg->length - qc->cursg_ofs, qc->sect_size);
 622
 623	trace_ata_sff_pio_transfer_data(qc, offset, count);
 624
 625	/*
 626	 * Split the transfer when it splits a page boundary.  Note that the
 627	 * split still has to be dword aligned like all ATA data transfers.
 628	 */
 629	WARN_ON_ONCE(offset % 4);
 630	if (offset + count > PAGE_SIZE) {
 631		unsigned int split_len = PAGE_SIZE - offset;
 632
 633		ata_pio_xfer(qc, page, offset, split_len);
 634		ata_pio_xfer(qc, nth_page(page, 1), 0, count - split_len);
 
 635	} else {
 636		ata_pio_xfer(qc, page, offset, count);
 637	}
 638
 639	qc->curbytes += count;
 640	qc->cursg_ofs += count;
 641
 642	if (qc->cursg_ofs == qc->cursg->length) {
 643		qc->cursg = sg_next(qc->cursg);
 644		if (!qc->cursg)
 645			ap->hsm_task_state = HSM_ST_LAST;
 646		qc->cursg_ofs = 0;
 647	}
 648}
 649
 650/**
 651 *	ata_pio_sectors - Transfer one or many sectors.
 652 *	@qc: Command on going
 653 *
 654 *	Transfer one or many sectors of data from/to the
 655 *	ATA device for the DRQ request.
 656 *
 657 *	LOCKING:
 658 *	Inherited from caller.
 659 */
 660static void ata_pio_sectors(struct ata_queued_cmd *qc)
 661{
 662	if (is_multi_taskfile(&qc->tf)) {
 663		/* READ/WRITE MULTIPLE */
 664		unsigned int nsect;
 665
 666		WARN_ON_ONCE(qc->dev->multi_count == 0);
 667
 668		nsect = min((qc->nbytes - qc->curbytes) / qc->sect_size,
 669			    qc->dev->multi_count);
 670		while (nsect--)
 671			ata_pio_sector(qc);
 672	} else
 673		ata_pio_sector(qc);
 674
 675	ata_sff_sync(qc->ap); /* flush */
 676}
 677
 678/**
 679 *	atapi_send_cdb - Write CDB bytes to hardware
 680 *	@ap: Port to which ATAPI device is attached.
 681 *	@qc: Taskfile currently active
 682 *
 683 *	When device has indicated its readiness to accept
 684 *	a CDB, this function is called.  Send the CDB.
 685 *
 686 *	LOCKING:
 687 *	caller.
 688 */
 689static void atapi_send_cdb(struct ata_port *ap, struct ata_queued_cmd *qc)
 690{
 691	/* send SCSI cdb */
 692	trace_atapi_send_cdb(qc, 0, qc->dev->cdb_len);
 693	WARN_ON_ONCE(qc->dev->cdb_len < 12);
 694
 695	ap->ops->sff_data_xfer(qc, qc->cdb, qc->dev->cdb_len, 1);
 696	ata_sff_sync(ap);
 697	/* FIXME: If the CDB is for DMA do we need to do the transition delay
 698	   or is bmdma_start guaranteed to do it ? */
 699	switch (qc->tf.protocol) {
 700	case ATAPI_PROT_PIO:
 701		ap->hsm_task_state = HSM_ST;
 702		break;
 703	case ATAPI_PROT_NODATA:
 704		ap->hsm_task_state = HSM_ST_LAST;
 705		break;
 706#ifdef CONFIG_ATA_BMDMA
 707	case ATAPI_PROT_DMA:
 708		ap->hsm_task_state = HSM_ST_LAST;
 709		/* initiate bmdma */
 710		trace_ata_bmdma_start(ap, &qc->tf, qc->tag);
 711		ap->ops->bmdma_start(qc);
 712		break;
 713#endif /* CONFIG_ATA_BMDMA */
 714	default:
 715		BUG();
 716	}
 717}
 718
 719/**
 720 *	__atapi_pio_bytes - Transfer data from/to the ATAPI device.
 721 *	@qc: Command on going
 722 *	@bytes: number of bytes
 723 *
 724 *	Transfer data from/to the ATAPI device.
 725 *
 726 *	LOCKING:
 727 *	Inherited from caller.
 728 *
 729 */
 730static int __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
 731{
 732	int rw = (qc->tf.flags & ATA_TFLAG_WRITE) ? WRITE : READ;
 733	struct ata_port *ap = qc->ap;
 734	struct ata_device *dev = qc->dev;
 735	struct ata_eh_info *ehi = &dev->link->eh_info;
 736	struct scatterlist *sg;
 737	struct page *page;
 738	unsigned char *buf;
 739	unsigned int offset, count, consumed;
 740
 741next_sg:
 742	sg = qc->cursg;
 743	if (unlikely(!sg)) {
 744		ata_ehi_push_desc(ehi, "unexpected or too much trailing data "
 745				  "buf=%u cur=%u bytes=%u",
 746				  qc->nbytes, qc->curbytes, bytes);
 747		return -1;
 748	}
 749
 750	page = sg_page(sg);
 751	offset = sg->offset + qc->cursg_ofs;
 752
 753	/* get the current page and offset */
 754	page = nth_page(page, (offset >> PAGE_SHIFT));
 755	offset %= PAGE_SIZE;
 756
 757	/* don't overrun current sg */
 758	count = min(sg->length - qc->cursg_ofs, bytes);
 759
 760	/* don't cross page boundaries */
 761	count = min(count, (unsigned int)PAGE_SIZE - offset);
 762
 763	trace_atapi_pio_transfer_data(qc, offset, count);
 764
 765	/* do the actual data transfer */
 766	buf = kmap_atomic(page);
 767	consumed = ap->ops->sff_data_xfer(qc, buf + offset, count, rw);
 768	kunmap_atomic(buf);
 769
 770	bytes -= min(bytes, consumed);
 771	qc->curbytes += count;
 772	qc->cursg_ofs += count;
 773
 774	if (qc->cursg_ofs == sg->length) {
 775		qc->cursg = sg_next(qc->cursg);
 776		qc->cursg_ofs = 0;
 777	}
 778
 779	/*
 780	 * There used to be a  WARN_ON_ONCE(qc->cursg && count != consumed);
 781	 * Unfortunately __atapi_pio_bytes doesn't know enough to do the WARN
 782	 * check correctly as it doesn't know if it is the last request being
 783	 * made. Somebody should implement a proper sanity check.
 784	 */
 785	if (bytes)
 786		goto next_sg;
 787	return 0;
 788}
 789
 790/**
 791 *	atapi_pio_bytes - Transfer data from/to the ATAPI device.
 792 *	@qc: Command on going
 793 *
 794 *	Transfer Transfer data from/to the ATAPI device.
 795 *
 796 *	LOCKING:
 797 *	Inherited from caller.
 798 */
 799static void atapi_pio_bytes(struct ata_queued_cmd *qc)
 800{
 801	struct ata_port *ap = qc->ap;
 802	struct ata_device *dev = qc->dev;
 803	struct ata_eh_info *ehi = &dev->link->eh_info;
 804	unsigned int ireason, bc_lo, bc_hi, bytes;
 805	int i_write, do_write = (qc->tf.flags & ATA_TFLAG_WRITE) ? 1 : 0;
 806
 807	/* Abuse qc->result_tf for temp storage of intermediate TF
 808	 * here to save some kernel stack usage.
 809	 * For normal completion, qc->result_tf is not relevant. For
 810	 * error, qc->result_tf is later overwritten by ata_qc_complete().
 811	 * So, the correctness of qc->result_tf is not affected.
 812	 */
 813	ap->ops->sff_tf_read(ap, &qc->result_tf);
 814	ireason = qc->result_tf.nsect;
 815	bc_lo = qc->result_tf.lbam;
 816	bc_hi = qc->result_tf.lbah;
 817	bytes = (bc_hi << 8) | bc_lo;
 818
 819	/* shall be cleared to zero, indicating xfer of data */
 820	if (unlikely(ireason & ATAPI_COD))
 821		goto atapi_check;
 822
 823	/* make sure transfer direction matches expected */
 824	i_write = ((ireason & ATAPI_IO) == 0) ? 1 : 0;
 825	if (unlikely(do_write != i_write))
 826		goto atapi_check;
 827
 828	if (unlikely(!bytes))
 829		goto atapi_check;
 830
 831	if (unlikely(__atapi_pio_bytes(qc, bytes)))
 832		goto err_out;
 833	ata_sff_sync(ap); /* flush */
 834
 835	return;
 836
 837 atapi_check:
 838	ata_ehi_push_desc(ehi, "ATAPI check failed (ireason=0x%x bytes=%u)",
 839			  ireason, bytes);
 840 err_out:
 841	qc->err_mask |= AC_ERR_HSM;
 842	ap->hsm_task_state = HSM_ST_ERR;
 843}
 844
 845/**
 846 *	ata_hsm_ok_in_wq - Check if the qc can be handled in the workqueue.
 847 *	@ap: the target ata_port
 848 *	@qc: qc on going
 849 *
 850 *	RETURNS:
 851 *	1 if ok in workqueue, 0 otherwise.
 852 */
 853static inline int ata_hsm_ok_in_wq(struct ata_port *ap,
 854						struct ata_queued_cmd *qc)
 855{
 856	if (qc->tf.flags & ATA_TFLAG_POLLING)
 857		return 1;
 858
 859	if (ap->hsm_task_state == HSM_ST_FIRST) {
 860		if (qc->tf.protocol == ATA_PROT_PIO &&
 861		   (qc->tf.flags & ATA_TFLAG_WRITE))
 862		    return 1;
 863
 864		if (ata_is_atapi(qc->tf.protocol) &&
 865		   !(qc->dev->flags & ATA_DFLAG_CDB_INTR))
 866			return 1;
 867	}
 868
 869	return 0;
 870}
 871
 872/**
 873 *	ata_hsm_qc_complete - finish a qc running on standard HSM
 874 *	@qc: Command to complete
 875 *	@in_wq: 1 if called from workqueue, 0 otherwise
 876 *
 877 *	Finish @qc which is running on standard HSM.
 878 *
 879 *	LOCKING:
 880 *	If @in_wq is zero, spin_lock_irqsave(host lock).
 881 *	Otherwise, none on entry and grabs host lock.
 882 */
 883static void ata_hsm_qc_complete(struct ata_queued_cmd *qc, int in_wq)
 884{
 885	struct ata_port *ap = qc->ap;
 886
 887	if (in_wq) {
 888		/* EH might have kicked in while host lock is released. */
 889		qc = ata_qc_from_tag(ap, qc->tag);
 890		if (qc) {
 891			if (likely(!(qc->err_mask & AC_ERR_HSM))) {
 892				ata_sff_irq_on(ap);
 
 
 
 
 
 
 
 
 
 893				ata_qc_complete(qc);
 894			} else
 895				ata_port_freeze(ap);
 896		}
 897	} else {
 898		if (likely(!(qc->err_mask & AC_ERR_HSM)))
 
 
 
 899			ata_qc_complete(qc);
 900		else
 901			ata_port_freeze(ap);
 902	}
 903}
 904
 905/**
 906 *	ata_sff_hsm_move - move the HSM to the next state.
 907 *	@ap: the target ata_port
 908 *	@qc: qc on going
 909 *	@status: current device status
 910 *	@in_wq: 1 if called from workqueue, 0 otherwise
 911 *
 912 *	RETURNS:
 913 *	1 when poll next status needed, 0 otherwise.
 914 */
 915int ata_sff_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc,
 916		     u8 status, int in_wq)
 917{
 918	struct ata_link *link = qc->dev->link;
 919	struct ata_eh_info *ehi = &link->eh_info;
 920	int poll_next;
 921
 922	lockdep_assert_held(ap->lock);
 923
 924	WARN_ON_ONCE((qc->flags & ATA_QCFLAG_ACTIVE) == 0);
 925
 926	/* Make sure ata_sff_qc_issue() does not throw things
 927	 * like DMA polling into the workqueue. Notice that
 928	 * in_wq is not equivalent to (qc->tf.flags & ATA_TFLAG_POLLING).
 929	 */
 930	WARN_ON_ONCE(in_wq != ata_hsm_ok_in_wq(ap, qc));
 931
 932fsm_start:
 933	trace_ata_sff_hsm_state(qc, status);
 934
 935	switch (ap->hsm_task_state) {
 936	case HSM_ST_FIRST:
 937		/* Send first data block or PACKET CDB */
 938
 939		/* If polling, we will stay in the work queue after
 940		 * sending the data. Otherwise, interrupt handler
 941		 * takes over after sending the data.
 942		 */
 943		poll_next = (qc->tf.flags & ATA_TFLAG_POLLING);
 944
 945		/* check device status */
 946		if (unlikely((status & ATA_DRQ) == 0)) {
 947			/* handle BSY=0, DRQ=0 as error */
 948			if (likely(status & (ATA_ERR | ATA_DF)))
 949				/* device stops HSM for abort/error */
 950				qc->err_mask |= AC_ERR_DEV;
 951			else {
 952				/* HSM violation. Let EH handle this */
 953				ata_ehi_push_desc(ehi,
 954					"ST_FIRST: !(DRQ|ERR|DF)");
 955				qc->err_mask |= AC_ERR_HSM;
 956			}
 957
 958			ap->hsm_task_state = HSM_ST_ERR;
 959			goto fsm_start;
 960		}
 961
 962		/* Device should not ask for data transfer (DRQ=1)
 963		 * when it finds something wrong.
 964		 * We ignore DRQ here and stop the HSM by
 965		 * changing hsm_task_state to HSM_ST_ERR and
 966		 * let the EH abort the command or reset the device.
 967		 */
 968		if (unlikely(status & (ATA_ERR | ATA_DF))) {
 969			/* Some ATAPI tape drives forget to clear the ERR bit
 970			 * when doing the next command (mostly request sense).
 971			 * We ignore ERR here to workaround and proceed sending
 972			 * the CDB.
 973			 */
 974			if (!(qc->dev->quirks & ATA_QUIRK_STUCK_ERR)) {
 975				ata_ehi_push_desc(ehi, "ST_FIRST: "
 976					"DRQ=1 with device error, "
 977					"dev_stat 0x%X", status);
 978				qc->err_mask |= AC_ERR_HSM;
 979				ap->hsm_task_state = HSM_ST_ERR;
 980				goto fsm_start;
 981			}
 982		}
 983
 984		if (qc->tf.protocol == ATA_PROT_PIO) {
 985			/* PIO data out protocol.
 986			 * send first data block.
 987			 */
 988
 989			/* ata_pio_sectors() might change the state
 990			 * to HSM_ST_LAST. so, the state is changed here
 991			 * before ata_pio_sectors().
 992			 */
 993			ap->hsm_task_state = HSM_ST;
 994			ata_pio_sectors(qc);
 995		} else
 996			/* send CDB */
 997			atapi_send_cdb(ap, qc);
 998
 999		/* if polling, ata_sff_pio_task() handles the rest.
1000		 * otherwise, interrupt handler takes over from here.
1001		 */
1002		break;
1003
1004	case HSM_ST:
1005		/* complete command or read/write the data register */
1006		if (qc->tf.protocol == ATAPI_PROT_PIO) {
1007			/* ATAPI PIO protocol */
1008			if ((status & ATA_DRQ) == 0) {
1009				/* No more data to transfer or device error.
1010				 * Device error will be tagged in HSM_ST_LAST.
1011				 */
1012				ap->hsm_task_state = HSM_ST_LAST;
1013				goto fsm_start;
1014			}
1015
1016			/* Device should not ask for data transfer (DRQ=1)
1017			 * when it finds something wrong.
1018			 * We ignore DRQ here and stop the HSM by
1019			 * changing hsm_task_state to HSM_ST_ERR and
1020			 * let the EH abort the command or reset the device.
1021			 */
1022			if (unlikely(status & (ATA_ERR | ATA_DF))) {
1023				ata_ehi_push_desc(ehi, "ST-ATAPI: "
1024					"DRQ=1 with device error, "
1025					"dev_stat 0x%X", status);
1026				qc->err_mask |= AC_ERR_HSM;
1027				ap->hsm_task_state = HSM_ST_ERR;
1028				goto fsm_start;
1029			}
1030
1031			atapi_pio_bytes(qc);
1032
1033			if (unlikely(ap->hsm_task_state == HSM_ST_ERR))
1034				/* bad ireason reported by device */
1035				goto fsm_start;
1036
1037		} else {
1038			/* ATA PIO protocol */
1039			if (unlikely((status & ATA_DRQ) == 0)) {
1040				/* handle BSY=0, DRQ=0 as error */
1041				if (likely(status & (ATA_ERR | ATA_DF))) {
1042					/* device stops HSM for abort/error */
1043					qc->err_mask |= AC_ERR_DEV;
1044
1045					/* If diagnostic failed and this is
1046					 * IDENTIFY, it's likely a phantom
1047					 * device.  Mark hint.
1048					 */
1049					if (qc->dev->quirks &
1050					    ATA_QUIRK_DIAGNOSTIC)
1051						qc->err_mask |=
1052							AC_ERR_NODEV_HINT;
1053				} else {
1054					/* HSM violation. Let EH handle this.
1055					 * Phantom devices also trigger this
1056					 * condition.  Mark hint.
1057					 */
1058					ata_ehi_push_desc(ehi, "ST-ATA: "
1059						"DRQ=0 without device error, "
1060						"dev_stat 0x%X", status);
1061					qc->err_mask |= AC_ERR_HSM |
1062							AC_ERR_NODEV_HINT;
1063				}
1064
1065				ap->hsm_task_state = HSM_ST_ERR;
1066				goto fsm_start;
1067			}
1068
1069			/* For PIO reads, some devices may ask for
1070			 * data transfer (DRQ=1) alone with ERR=1.
1071			 * We respect DRQ here and transfer one
1072			 * block of junk data before changing the
1073			 * hsm_task_state to HSM_ST_ERR.
1074			 *
1075			 * For PIO writes, ERR=1 DRQ=1 doesn't make
1076			 * sense since the data block has been
1077			 * transferred to the device.
1078			 */
1079			if (unlikely(status & (ATA_ERR | ATA_DF))) {
1080				/* data might be corrputed */
1081				qc->err_mask |= AC_ERR_DEV;
1082
1083				if (!(qc->tf.flags & ATA_TFLAG_WRITE)) {
1084					ata_pio_sectors(qc);
1085					status = ata_wait_idle(ap);
1086				}
1087
1088				if (status & (ATA_BUSY | ATA_DRQ)) {
1089					ata_ehi_push_desc(ehi, "ST-ATA: "
1090						"BUSY|DRQ persists on ERR|DF, "
1091						"dev_stat 0x%X", status);
1092					qc->err_mask |= AC_ERR_HSM;
1093				}
1094
1095				/* There are oddball controllers with
1096				 * status register stuck at 0x7f and
1097				 * lbal/m/h at zero which makes it
1098				 * pass all other presence detection
1099				 * mechanisms we have.  Set NODEV_HINT
1100				 * for it.  Kernel bz#7241.
1101				 */
1102				if (status == 0x7f)
1103					qc->err_mask |= AC_ERR_NODEV_HINT;
1104
1105				/* ata_pio_sectors() might change the
1106				 * state to HSM_ST_LAST. so, the state
1107				 * is changed after ata_pio_sectors().
1108				 */
1109				ap->hsm_task_state = HSM_ST_ERR;
1110				goto fsm_start;
1111			}
1112
1113			ata_pio_sectors(qc);
1114
1115			if (ap->hsm_task_state == HSM_ST_LAST &&
1116			    (!(qc->tf.flags & ATA_TFLAG_WRITE))) {
1117				/* all data read */
1118				status = ata_wait_idle(ap);
1119				goto fsm_start;
1120			}
1121		}
1122
1123		poll_next = 1;
1124		break;
1125
1126	case HSM_ST_LAST:
1127		if (unlikely(!ata_ok(status))) {
1128			qc->err_mask |= __ac_err_mask(status);
1129			ap->hsm_task_state = HSM_ST_ERR;
1130			goto fsm_start;
1131		}
1132
1133		/* no more data to transfer */
1134		trace_ata_sff_hsm_command_complete(qc, status);
1135
1136		WARN_ON_ONCE(qc->err_mask & (AC_ERR_DEV | AC_ERR_HSM));
1137
1138		ap->hsm_task_state = HSM_ST_IDLE;
1139
1140		/* complete taskfile transaction */
1141		ata_hsm_qc_complete(qc, in_wq);
1142
1143		poll_next = 0;
1144		break;
1145
1146	case HSM_ST_ERR:
1147		ap->hsm_task_state = HSM_ST_IDLE;
1148
1149		/* complete taskfile transaction */
1150		ata_hsm_qc_complete(qc, in_wq);
1151
1152		poll_next = 0;
1153		break;
1154	default:
1155		poll_next = 0;
1156		WARN(true, "ata%d: SFF host state machine in invalid state %d",
1157		     ap->print_id, ap->hsm_task_state);
1158	}
1159
1160	return poll_next;
1161}
1162EXPORT_SYMBOL_GPL(ata_sff_hsm_move);
1163
1164void ata_sff_queue_work(struct work_struct *work)
1165{
1166	queue_work(ata_sff_wq, work);
1167}
1168EXPORT_SYMBOL_GPL(ata_sff_queue_work);
1169
1170void ata_sff_queue_delayed_work(struct delayed_work *dwork, unsigned long delay)
1171{
1172	queue_delayed_work(ata_sff_wq, dwork, delay);
1173}
1174EXPORT_SYMBOL_GPL(ata_sff_queue_delayed_work);
1175
1176void ata_sff_queue_pio_task(struct ata_link *link, unsigned long delay)
1177{
1178	struct ata_port *ap = link->ap;
1179
1180	WARN_ON((ap->sff_pio_task_link != NULL) &&
1181		(ap->sff_pio_task_link != link));
1182	ap->sff_pio_task_link = link;
1183
1184	/* may fail if ata_sff_flush_pio_task() in progress */
1185	ata_sff_queue_delayed_work(&ap->sff_pio_task, msecs_to_jiffies(delay));
1186}
1187EXPORT_SYMBOL_GPL(ata_sff_queue_pio_task);
1188
1189void ata_sff_flush_pio_task(struct ata_port *ap)
1190{
1191	trace_ata_sff_flush_pio_task(ap);
1192
1193	cancel_delayed_work_sync(&ap->sff_pio_task);
1194
1195	/*
1196	 * We wanna reset the HSM state to IDLE.  If we do so without
1197	 * grabbing the port lock, critical sections protected by it which
1198	 * expect the HSM state to stay stable may get surprised.  For
1199	 * example, we may set IDLE in between the time
1200	 * __ata_sff_port_intr() checks for HSM_ST_IDLE and before it calls
1201	 * ata_sff_hsm_move() causing ata_sff_hsm_move() to BUG().
1202	 */
1203	spin_lock_irq(ap->lock);
1204	ap->hsm_task_state = HSM_ST_IDLE;
1205	spin_unlock_irq(ap->lock);
1206
1207	ap->sff_pio_task_link = NULL;
1208}
1209
1210static void ata_sff_pio_task(struct work_struct *work)
1211{
1212	struct ata_port *ap =
1213		container_of(work, struct ata_port, sff_pio_task.work);
1214	struct ata_link *link = ap->sff_pio_task_link;
1215	struct ata_queued_cmd *qc;
1216	u8 status;
1217	int poll_next;
1218
1219	spin_lock_irq(ap->lock);
1220
1221	BUG_ON(ap->sff_pio_task_link == NULL);
1222	/* qc can be NULL if timeout occurred */
1223	qc = ata_qc_from_tag(ap, link->active_tag);
1224	if (!qc) {
1225		ap->sff_pio_task_link = NULL;
1226		goto out_unlock;
1227	}
1228
1229fsm_start:
1230	WARN_ON_ONCE(ap->hsm_task_state == HSM_ST_IDLE);
1231
1232	/*
1233	 * This is purely heuristic.  This is a fast path.
1234	 * Sometimes when we enter, BSY will be cleared in
1235	 * a chk-status or two.  If not, the drive is probably seeking
1236	 * or something.  Snooze for a couple msecs, then
1237	 * chk-status again.  If still busy, queue delayed work.
1238	 */
1239	status = ata_sff_busy_wait(ap, ATA_BUSY, 5);
1240	if (status & ATA_BUSY) {
1241		spin_unlock_irq(ap->lock);
1242		ata_msleep(ap, 2);
1243		spin_lock_irq(ap->lock);
1244
1245		status = ata_sff_busy_wait(ap, ATA_BUSY, 10);
1246		if (status & ATA_BUSY) {
1247			ata_sff_queue_pio_task(link, ATA_SHORT_PAUSE);
1248			goto out_unlock;
1249		}
1250	}
1251
1252	/*
1253	 * hsm_move() may trigger another command to be processed.
1254	 * clean the link beforehand.
1255	 */
1256	ap->sff_pio_task_link = NULL;
1257	/* move the HSM */
1258	poll_next = ata_sff_hsm_move(ap, qc, status, 1);
1259
1260	/* another command or interrupt handler
1261	 * may be running at this point.
1262	 */
1263	if (poll_next)
1264		goto fsm_start;
1265out_unlock:
1266	spin_unlock_irq(ap->lock);
1267}
1268
1269/**
1270 *	ata_sff_qc_issue - issue taskfile to a SFF controller
1271 *	@qc: command to issue to device
1272 *
1273 *	This function issues a PIO or NODATA command to a SFF
1274 *	controller.
1275 *
1276 *	LOCKING:
1277 *	spin_lock_irqsave(host lock)
1278 *
1279 *	RETURNS:
1280 *	Zero on success, AC_ERR_* mask on failure
1281 */
1282unsigned int ata_sff_qc_issue(struct ata_queued_cmd *qc)
1283{
1284	struct ata_port *ap = qc->ap;
1285	struct ata_link *link = qc->dev->link;
1286
1287	/* Use polling pio if the LLD doesn't handle
1288	 * interrupt driven pio and atapi CDB interrupt.
1289	 */
1290	if (ap->flags & ATA_FLAG_PIO_POLLING)
1291		qc->tf.flags |= ATA_TFLAG_POLLING;
1292
1293	/* select the device */
1294	ata_dev_select(ap, qc->dev->devno, 1, 0);
1295
1296	/* start the command */
1297	switch (qc->tf.protocol) {
1298	case ATA_PROT_NODATA:
1299		if (qc->tf.flags & ATA_TFLAG_POLLING)
1300			ata_qc_set_polling(qc);
1301
1302		ata_tf_to_host(ap, &qc->tf, qc->tag);
1303		ap->hsm_task_state = HSM_ST_LAST;
1304
1305		if (qc->tf.flags & ATA_TFLAG_POLLING)
1306			ata_sff_queue_pio_task(link, 0);
1307
1308		break;
1309
1310	case ATA_PROT_PIO:
1311		if (qc->tf.flags & ATA_TFLAG_POLLING)
1312			ata_qc_set_polling(qc);
1313
1314		ata_tf_to_host(ap, &qc->tf, qc->tag);
1315
1316		if (qc->tf.flags & ATA_TFLAG_WRITE) {
1317			/* PIO data out protocol */
1318			ap->hsm_task_state = HSM_ST_FIRST;
1319			ata_sff_queue_pio_task(link, 0);
1320
1321			/* always send first data block using the
1322			 * ata_sff_pio_task() codepath.
1323			 */
1324		} else {
1325			/* PIO data in protocol */
1326			ap->hsm_task_state = HSM_ST;
1327
1328			if (qc->tf.flags & ATA_TFLAG_POLLING)
1329				ata_sff_queue_pio_task(link, 0);
1330
1331			/* if polling, ata_sff_pio_task() handles the
1332			 * rest.  otherwise, interrupt handler takes
1333			 * over from here.
1334			 */
1335		}
1336
1337		break;
1338
1339	case ATAPI_PROT_PIO:
1340	case ATAPI_PROT_NODATA:
1341		if (qc->tf.flags & ATA_TFLAG_POLLING)
1342			ata_qc_set_polling(qc);
1343
1344		ata_tf_to_host(ap, &qc->tf, qc->tag);
1345
1346		ap->hsm_task_state = HSM_ST_FIRST;
1347
1348		/* send cdb by polling if no cdb interrupt */
1349		if ((!(qc->dev->flags & ATA_DFLAG_CDB_INTR)) ||
1350		    (qc->tf.flags & ATA_TFLAG_POLLING))
1351			ata_sff_queue_pio_task(link, 0);
1352		break;
1353
1354	default:
1355		return AC_ERR_SYSTEM;
1356	}
1357
1358	return 0;
1359}
1360EXPORT_SYMBOL_GPL(ata_sff_qc_issue);
1361
1362/**
1363 *	ata_sff_qc_fill_rtf - fill result TF using ->sff_tf_read
1364 *	@qc: qc to fill result TF for
1365 *
1366 *	@qc is finished and result TF needs to be filled.  Fill it
1367 *	using ->sff_tf_read.
1368 *
1369 *	LOCKING:
1370 *	spin_lock_irqsave(host lock)
 
 
 
1371 */
1372void ata_sff_qc_fill_rtf(struct ata_queued_cmd *qc)
1373{
1374	qc->ap->ops->sff_tf_read(qc->ap, &qc->result_tf);
 
1375}
1376EXPORT_SYMBOL_GPL(ata_sff_qc_fill_rtf);
1377
1378static unsigned int ata_sff_idle_irq(struct ata_port *ap)
1379{
1380	ap->stats.idle_irq++;
1381
1382#ifdef ATA_IRQ_TRAP
1383	if ((ap->stats.idle_irq % 1000) == 0) {
1384		ap->ops->sff_check_status(ap);
1385		if (ap->ops->sff_irq_clear)
1386			ap->ops->sff_irq_clear(ap);
1387		ata_port_warn(ap, "irq trap\n");
1388		return 1;
1389	}
1390#endif
1391	return 0;	/* irq not handled */
1392}
1393
1394static unsigned int __ata_sff_port_intr(struct ata_port *ap,
1395					struct ata_queued_cmd *qc,
1396					bool hsmv_on_idle)
1397{
1398	u8 status;
1399
1400	trace_ata_sff_port_intr(qc, hsmv_on_idle);
1401
1402	/* Check whether we are expecting interrupt in this state */
1403	switch (ap->hsm_task_state) {
1404	case HSM_ST_FIRST:
1405		/* Some pre-ATAPI-4 devices assert INTRQ
1406		 * at this state when ready to receive CDB.
1407		 */
1408
1409		/* Check the ATA_DFLAG_CDB_INTR flag is enough here.
1410		 * The flag was turned on only for atapi devices.  No
1411		 * need to check ata_is_atapi(qc->tf.protocol) again.
1412		 */
1413		if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
1414			return ata_sff_idle_irq(ap);
1415		break;
1416	case HSM_ST_IDLE:
1417		return ata_sff_idle_irq(ap);
1418	default:
1419		break;
1420	}
1421
1422	/* check main status, clearing INTRQ if needed */
1423	status = ata_sff_irq_status(ap);
1424	if (status & ATA_BUSY) {
1425		if (hsmv_on_idle) {
1426			/* BMDMA engine is already stopped, we're screwed */
1427			qc->err_mask |= AC_ERR_HSM;
1428			ap->hsm_task_state = HSM_ST_ERR;
1429		} else
1430			return ata_sff_idle_irq(ap);
1431	}
1432
1433	/* clear irq events */
1434	if (ap->ops->sff_irq_clear)
1435		ap->ops->sff_irq_clear(ap);
1436
1437	ata_sff_hsm_move(ap, qc, status, 0);
1438
1439	return 1;	/* irq handled */
1440}
1441
1442/**
1443 *	ata_sff_port_intr - Handle SFF port interrupt
1444 *	@ap: Port on which interrupt arrived (possibly...)
1445 *	@qc: Taskfile currently active in engine
1446 *
1447 *	Handle port interrupt for given queued command.
1448 *
1449 *	LOCKING:
1450 *	spin_lock_irqsave(host lock)
1451 *
1452 *	RETURNS:
1453 *	One if interrupt was handled, zero if not (shared irq).
1454 */
1455unsigned int ata_sff_port_intr(struct ata_port *ap, struct ata_queued_cmd *qc)
1456{
1457	return __ata_sff_port_intr(ap, qc, false);
1458}
1459EXPORT_SYMBOL_GPL(ata_sff_port_intr);
1460
1461static inline irqreturn_t __ata_sff_interrupt(int irq, void *dev_instance,
1462	unsigned int (*port_intr)(struct ata_port *, struct ata_queued_cmd *))
1463{
1464	struct ata_host *host = dev_instance;
1465	bool retried = false;
1466	unsigned int i;
1467	unsigned int handled, idle, polling;
1468	unsigned long flags;
1469
1470	/* TODO: make _irqsave conditional on x86 PCI IDE legacy mode */
1471	spin_lock_irqsave(&host->lock, flags);
1472
1473retry:
1474	handled = idle = polling = 0;
1475	for (i = 0; i < host->n_ports; i++) {
1476		struct ata_port *ap = host->ports[i];
1477		struct ata_queued_cmd *qc;
1478
1479		qc = ata_qc_from_tag(ap, ap->link.active_tag);
1480		if (qc) {
1481			if (!(qc->tf.flags & ATA_TFLAG_POLLING))
1482				handled |= port_intr(ap, qc);
1483			else
1484				polling |= 1 << i;
1485		} else
1486			idle |= 1 << i;
1487	}
1488
1489	/*
1490	 * If no port was expecting IRQ but the controller is actually
1491	 * asserting IRQ line, nobody cared will ensue.  Check IRQ
1492	 * pending status if available and clear spurious IRQ.
1493	 */
1494	if (!handled && !retried) {
1495		bool retry = false;
1496
1497		for (i = 0; i < host->n_ports; i++) {
1498			struct ata_port *ap = host->ports[i];
1499
1500			if (polling & (1 << i))
1501				continue;
1502
1503			if (!ap->ops->sff_irq_check ||
1504			    !ap->ops->sff_irq_check(ap))
1505				continue;
1506
1507			if (idle & (1 << i)) {
1508				ap->ops->sff_check_status(ap);
1509				if (ap->ops->sff_irq_clear)
1510					ap->ops->sff_irq_clear(ap);
1511			} else {
1512				/* clear INTRQ and check if BUSY cleared */
1513				if (!(ap->ops->sff_check_status(ap) & ATA_BUSY))
1514					retry |= true;
1515				/*
1516				 * With command in flight, we can't do
1517				 * sff_irq_clear() w/o racing with completion.
1518				 */
1519			}
1520		}
1521
1522		if (retry) {
1523			retried = true;
1524			goto retry;
1525		}
1526	}
1527
1528	spin_unlock_irqrestore(&host->lock, flags);
1529
1530	return IRQ_RETVAL(handled);
1531}
1532
1533/**
1534 *	ata_sff_interrupt - Default SFF ATA host interrupt handler
1535 *	@irq: irq line (unused)
1536 *	@dev_instance: pointer to our ata_host information structure
1537 *
1538 *	Default interrupt handler for PCI IDE devices.  Calls
1539 *	ata_sff_port_intr() for each port that is not disabled.
1540 *
1541 *	LOCKING:
1542 *	Obtains host lock during operation.
1543 *
1544 *	RETURNS:
1545 *	IRQ_NONE or IRQ_HANDLED.
1546 */
1547irqreturn_t ata_sff_interrupt(int irq, void *dev_instance)
1548{
1549	return __ata_sff_interrupt(irq, dev_instance, ata_sff_port_intr);
1550}
1551EXPORT_SYMBOL_GPL(ata_sff_interrupt);
1552
1553/**
1554 *	ata_sff_lost_interrupt	-	Check for an apparent lost interrupt
1555 *	@ap: port that appears to have timed out
1556 *
1557 *	Called from the libata error handlers when the core code suspects
1558 *	an interrupt has been lost. If it has complete anything we can and
1559 *	then return. Interface must support altstatus for this faster
1560 *	recovery to occur.
1561 *
1562 *	Locking:
1563 *	Caller holds host lock
1564 */
1565
1566void ata_sff_lost_interrupt(struct ata_port *ap)
1567{
1568	u8 status = 0;
1569	struct ata_queued_cmd *qc;
1570
1571	/* Only one outstanding command per SFF channel */
1572	qc = ata_qc_from_tag(ap, ap->link.active_tag);
1573	/* We cannot lose an interrupt on a non-existent or polled command */
1574	if (!qc || qc->tf.flags & ATA_TFLAG_POLLING)
1575		return;
1576	/* See if the controller thinks it is still busy - if so the command
1577	   isn't a lost IRQ but is still in progress */
1578	if (WARN_ON_ONCE(!ata_sff_altstatus(ap, &status)))
1579		return;
1580	if (status & ATA_BUSY)
1581		return;
1582
1583	/* There was a command running, we are no longer busy and we have
1584	   no interrupt. */
1585	ata_port_warn(ap, "lost interrupt (Status 0x%x)\n", status);
1586	/* Run the host interrupt logic as if the interrupt had not been
1587	   lost */
1588	ata_sff_port_intr(ap, qc);
1589}
1590EXPORT_SYMBOL_GPL(ata_sff_lost_interrupt);
1591
1592/**
1593 *	ata_sff_freeze - Freeze SFF controller port
1594 *	@ap: port to freeze
1595 *
1596 *	Freeze SFF controller port.
1597 *
1598 *	LOCKING:
1599 *	Inherited from caller.
1600 */
1601void ata_sff_freeze(struct ata_port *ap)
1602{
1603	ap->ctl |= ATA_NIEN;
1604	ap->last_ctl = ap->ctl;
1605
1606	ata_sff_set_devctl(ap, ap->ctl);
1607
1608	/* Under certain circumstances, some controllers raise IRQ on
1609	 * ATA_NIEN manipulation.  Also, many controllers fail to mask
1610	 * previously pending IRQ on ATA_NIEN assertion.  Clear it.
1611	 */
1612	ap->ops->sff_check_status(ap);
1613
1614	if (ap->ops->sff_irq_clear)
1615		ap->ops->sff_irq_clear(ap);
1616}
1617EXPORT_SYMBOL_GPL(ata_sff_freeze);
1618
1619/**
1620 *	ata_sff_thaw - Thaw SFF controller port
1621 *	@ap: port to thaw
1622 *
1623 *	Thaw SFF controller port.
1624 *
1625 *	LOCKING:
1626 *	Inherited from caller.
1627 */
1628void ata_sff_thaw(struct ata_port *ap)
1629{
1630	/* clear & re-enable interrupts */
1631	ap->ops->sff_check_status(ap);
1632	if (ap->ops->sff_irq_clear)
1633		ap->ops->sff_irq_clear(ap);
1634	ata_sff_irq_on(ap);
1635}
1636EXPORT_SYMBOL_GPL(ata_sff_thaw);
1637
1638/**
1639 *	ata_sff_prereset - prepare SFF link for reset
1640 *	@link: SFF link to be reset
1641 *	@deadline: deadline jiffies for the operation
1642 *
1643 *	SFF link @link is about to be reset.  Initialize it.  It first
1644 *	calls ata_std_prereset() and wait for !BSY if the port is
1645 *	being softreset.
1646 *
1647 *	LOCKING:
1648 *	Kernel thread context (may sleep)
1649 *
1650 *	RETURNS:
1651 *	Always 0.
1652 */
1653int ata_sff_prereset(struct ata_link *link, unsigned long deadline)
1654{
1655	struct ata_eh_context *ehc = &link->eh_context;
1656	int rc;
1657
1658	/* The standard prereset is best-effort and always returns 0 */
1659	ata_std_prereset(link, deadline);
1660
1661	/* if we're about to do hardreset, nothing more to do */
1662	if (ehc->i.action & ATA_EH_HARDRESET)
1663		return 0;
1664
1665	/* wait for !BSY if we don't know that no device is attached */
1666	if (!ata_link_offline(link)) {
1667		rc = ata_sff_wait_ready(link, deadline);
1668		if (rc && rc != -ENODEV) {
1669			ata_link_warn(link,
1670				      "device not ready (errno=%d), forcing hardreset\n",
1671				      rc);
1672			ehc->i.action |= ATA_EH_HARDRESET;
1673		}
1674	}
1675
1676	return 0;
1677}
1678EXPORT_SYMBOL_GPL(ata_sff_prereset);
1679
1680/**
1681 *	ata_devchk - PATA device presence detection
1682 *	@ap: ATA channel to examine
1683 *	@device: Device to examine (starting at zero)
1684 *
1685 *	This technique was originally described in
1686 *	Hale Landis's ATADRVR (www.ata-atapi.com), and
1687 *	later found its way into the ATA/ATAPI spec.
1688 *
1689 *	Write a pattern to the ATA shadow registers,
1690 *	and if a device is present, it will respond by
1691 *	correctly storing and echoing back the
1692 *	ATA shadow register contents.
1693 *
1694 *	RETURN:
1695 *	true if device is present, false if not.
1696 *
1697 *	LOCKING:
1698 *	caller.
1699 */
1700static bool ata_devchk(struct ata_port *ap, unsigned int device)
1701{
1702	struct ata_ioports *ioaddr = &ap->ioaddr;
1703	u8 nsect, lbal;
1704
1705	ap->ops->sff_dev_select(ap, device);
1706
1707	iowrite8(0x55, ioaddr->nsect_addr);
1708	iowrite8(0xaa, ioaddr->lbal_addr);
1709
1710	iowrite8(0xaa, ioaddr->nsect_addr);
1711	iowrite8(0x55, ioaddr->lbal_addr);
1712
1713	iowrite8(0x55, ioaddr->nsect_addr);
1714	iowrite8(0xaa, ioaddr->lbal_addr);
1715
1716	nsect = ioread8(ioaddr->nsect_addr);
1717	lbal = ioread8(ioaddr->lbal_addr);
1718
1719	if ((nsect == 0x55) && (lbal == 0xaa))
1720		return true;	/* we found a device */
1721
1722	return false;		/* nothing found */
1723}
1724
1725/**
1726 *	ata_sff_dev_classify - Parse returned ATA device signature
1727 *	@dev: ATA device to classify (starting at zero)
1728 *	@present: device seems present
1729 *	@r_err: Value of error register on completion
1730 *
1731 *	After an event -- SRST, E.D.D., or SATA COMRESET -- occurs,
1732 *	an ATA/ATAPI-defined set of values is placed in the ATA
1733 *	shadow registers, indicating the results of device detection
1734 *	and diagnostics.
1735 *
1736 *	Select the ATA device, and read the values from the ATA shadow
1737 *	registers.  Then parse according to the Error register value,
1738 *	and the spec-defined values examined by ata_dev_classify().
1739 *
1740 *	LOCKING:
1741 *	caller.
1742 *
1743 *	RETURNS:
1744 *	Device type - %ATA_DEV_ATA, %ATA_DEV_ATAPI or %ATA_DEV_NONE.
1745 */
1746unsigned int ata_sff_dev_classify(struct ata_device *dev, int present,
1747				  u8 *r_err)
1748{
1749	struct ata_port *ap = dev->link->ap;
1750	struct ata_taskfile tf;
1751	unsigned int class;
1752	u8 err;
1753
1754	ap->ops->sff_dev_select(ap, dev->devno);
1755
1756	memset(&tf, 0, sizeof(tf));
1757
1758	ap->ops->sff_tf_read(ap, &tf);
1759	err = tf.error;
1760	if (r_err)
1761		*r_err = err;
1762
1763	/* see if device passed diags: continue and warn later */
1764	if (err == 0)
1765		/* diagnostic fail : do nothing _YET_ */
1766		dev->quirks |= ATA_QUIRK_DIAGNOSTIC;
1767	else if (err == 1)
1768		/* do nothing */ ;
1769	else if ((dev->devno == 0) && (err == 0x81))
1770		/* do nothing */ ;
1771	else
1772		return ATA_DEV_NONE;
1773
1774	/* determine if device is ATA or ATAPI */
1775	class = ata_port_classify(ap, &tf);
1776	switch (class) {
1777	case ATA_DEV_UNKNOWN:
1778		/*
1779		 * If the device failed diagnostic, it's likely to
1780		 * have reported incorrect device signature too.
1781		 * Assume ATA device if the device seems present but
1782		 * device signature is invalid with diagnostic
1783		 * failure.
1784		 */
1785		if (present && (dev->quirks & ATA_QUIRK_DIAGNOSTIC))
1786			class = ATA_DEV_ATA;
1787		else
1788			class = ATA_DEV_NONE;
1789		break;
1790	case ATA_DEV_ATA:
1791		if (ap->ops->sff_check_status(ap) == 0)
1792			class = ATA_DEV_NONE;
1793		break;
1794	}
1795	return class;
1796}
1797EXPORT_SYMBOL_GPL(ata_sff_dev_classify);
1798
1799/**
1800 *	ata_sff_wait_after_reset - wait for devices to become ready after reset
1801 *	@link: SFF link which is just reset
1802 *	@devmask: mask of present devices
1803 *	@deadline: deadline jiffies for the operation
1804 *
1805 *	Wait devices attached to SFF @link to become ready after
1806 *	reset.  It contains preceding 150ms wait to avoid accessing TF
1807 *	status register too early.
1808 *
1809 *	LOCKING:
1810 *	Kernel thread context (may sleep).
1811 *
1812 *	RETURNS:
1813 *	0 on success, -ENODEV if some or all of devices in @devmask
1814 *	don't seem to exist.  -errno on other errors.
1815 */
1816int ata_sff_wait_after_reset(struct ata_link *link, unsigned int devmask,
1817			     unsigned long deadline)
1818{
1819	struct ata_port *ap = link->ap;
1820	struct ata_ioports *ioaddr = &ap->ioaddr;
1821	unsigned int dev0 = devmask & (1 << 0);
1822	unsigned int dev1 = devmask & (1 << 1);
1823	int rc, ret = 0;
1824
1825	ata_msleep(ap, ATA_WAIT_AFTER_RESET);
1826
1827	/* always check readiness of the master device */
1828	rc = ata_sff_wait_ready(link, deadline);
1829	/* -ENODEV means the odd clown forgot the D7 pulldown resistor
1830	 * and TF status is 0xff, bail out on it too.
1831	 */
1832	if (rc)
1833		return rc;
1834
1835	/* if device 1 was found in ata_devchk, wait for register
1836	 * access briefly, then wait for BSY to clear.
1837	 */
1838	if (dev1) {
1839		int i;
1840
1841		ap->ops->sff_dev_select(ap, 1);
1842
1843		/* Wait for register access.  Some ATAPI devices fail
1844		 * to set nsect/lbal after reset, so don't waste too
1845		 * much time on it.  We're gonna wait for !BSY anyway.
1846		 */
1847		for (i = 0; i < 2; i++) {
1848			u8 nsect, lbal;
1849
1850			nsect = ioread8(ioaddr->nsect_addr);
1851			lbal = ioread8(ioaddr->lbal_addr);
1852			if ((nsect == 1) && (lbal == 1))
1853				break;
1854			ata_msleep(ap, 50);	/* give drive a breather */
1855		}
1856
1857		rc = ata_sff_wait_ready(link, deadline);
1858		if (rc) {
1859			if (rc != -ENODEV)
1860				return rc;
1861			ret = rc;
1862		}
1863	}
1864
1865	/* is all this really necessary? */
1866	ap->ops->sff_dev_select(ap, 0);
1867	if (dev1)
1868		ap->ops->sff_dev_select(ap, 1);
1869	if (dev0)
1870		ap->ops->sff_dev_select(ap, 0);
1871
1872	return ret;
1873}
1874EXPORT_SYMBOL_GPL(ata_sff_wait_after_reset);
1875
1876static int ata_bus_softreset(struct ata_port *ap, unsigned int devmask,
1877			     unsigned long deadline)
1878{
1879	struct ata_ioports *ioaddr = &ap->ioaddr;
1880
1881	if (ap->ioaddr.ctl_addr) {
1882		/* software reset.  causes dev0 to be selected */
1883		iowrite8(ap->ctl, ioaddr->ctl_addr);
1884		udelay(20);	/* FIXME: flush */
1885		iowrite8(ap->ctl | ATA_SRST, ioaddr->ctl_addr);
1886		udelay(20);	/* FIXME: flush */
1887		iowrite8(ap->ctl, ioaddr->ctl_addr);
1888		ap->last_ctl = ap->ctl;
1889	}
1890
1891	/* wait the port to become ready */
1892	return ata_sff_wait_after_reset(&ap->link, devmask, deadline);
1893}
1894
1895/**
1896 *	ata_sff_softreset - reset host port via ATA SRST
1897 *	@link: ATA link to reset
1898 *	@classes: resulting classes of attached devices
1899 *	@deadline: deadline jiffies for the operation
1900 *
1901 *	Reset host port using ATA SRST.
1902 *
1903 *	LOCKING:
1904 *	Kernel thread context (may sleep)
1905 *
1906 *	RETURNS:
1907 *	0 on success, -errno otherwise.
1908 */
1909int ata_sff_softreset(struct ata_link *link, unsigned int *classes,
1910		      unsigned long deadline)
1911{
1912	struct ata_port *ap = link->ap;
1913	unsigned int slave_possible = ap->flags & ATA_FLAG_SLAVE_POSS;
1914	unsigned int devmask = 0;
1915	int rc;
1916	u8 err;
1917
1918	/* determine if device 0/1 are present */
1919	if (ata_devchk(ap, 0))
1920		devmask |= (1 << 0);
1921	if (slave_possible && ata_devchk(ap, 1))
1922		devmask |= (1 << 1);
1923
1924	/* select device 0 again */
1925	ap->ops->sff_dev_select(ap, 0);
1926
1927	/* issue bus reset */
1928	rc = ata_bus_softreset(ap, devmask, deadline);
1929	/* if link is occupied, -ENODEV too is an error */
1930	if (rc && (rc != -ENODEV || sata_scr_valid(link))) {
1931		ata_link_err(link, "SRST failed (errno=%d)\n", rc);
1932		return rc;
1933	}
1934
1935	/* determine by signature whether we have ATA or ATAPI devices */
1936	classes[0] = ata_sff_dev_classify(&link->device[0],
1937					  devmask & (1 << 0), &err);
1938	if (slave_possible && err != 0x81)
1939		classes[1] = ata_sff_dev_classify(&link->device[1],
1940						  devmask & (1 << 1), &err);
1941
1942	return 0;
1943}
1944EXPORT_SYMBOL_GPL(ata_sff_softreset);
1945
1946/**
1947 *	sata_sff_hardreset - reset host port via SATA phy reset
1948 *	@link: link to reset
1949 *	@class: resulting class of attached device
1950 *	@deadline: deadline jiffies for the operation
1951 *
1952 *	SATA phy-reset host port using DET bits of SControl register,
1953 *	wait for !BSY and classify the attached device.
1954 *
1955 *	LOCKING:
1956 *	Kernel thread context (may sleep)
1957 *
1958 *	RETURNS:
1959 *	0 on success, -errno otherwise.
1960 */
1961int sata_sff_hardreset(struct ata_link *link, unsigned int *class,
1962		       unsigned long deadline)
1963{
1964	struct ata_eh_context *ehc = &link->eh_context;
1965	const unsigned int *timing = sata_ehc_deb_timing(ehc);
1966	bool online;
1967	int rc;
1968
1969	rc = sata_link_hardreset(link, timing, deadline, &online,
1970				 ata_sff_check_ready);
1971	if (online)
1972		*class = ata_sff_dev_classify(link->device, 1, NULL);
1973
1974	return rc;
1975}
1976EXPORT_SYMBOL_GPL(sata_sff_hardreset);
1977
1978/**
1979 *	ata_sff_postreset - SFF postreset callback
1980 *	@link: the target SFF ata_link
1981 *	@classes: classes of attached devices
1982 *
1983 *	This function is invoked after a successful reset.  It first
1984 *	calls ata_std_postreset() and performs SFF specific postreset
1985 *	processing.
1986 *
1987 *	LOCKING:
1988 *	Kernel thread context (may sleep)
1989 */
1990void ata_sff_postreset(struct ata_link *link, unsigned int *classes)
1991{
1992	struct ata_port *ap = link->ap;
1993
1994	ata_std_postreset(link, classes);
1995
1996	/* is double-select really necessary? */
1997	if (classes[0] != ATA_DEV_NONE)
1998		ap->ops->sff_dev_select(ap, 1);
1999	if (classes[1] != ATA_DEV_NONE)
2000		ap->ops->sff_dev_select(ap, 0);
2001
2002	/* bail out if no device is present */
2003	if (classes[0] == ATA_DEV_NONE && classes[1] == ATA_DEV_NONE)
2004		return;
2005
2006	/* set up device control */
2007	if (ata_sff_set_devctl(ap, ap->ctl))
2008		ap->last_ctl = ap->ctl;
2009}
2010EXPORT_SYMBOL_GPL(ata_sff_postreset);
2011
2012/**
2013 *	ata_sff_drain_fifo - Stock FIFO drain logic for SFF controllers
2014 *	@qc: command
2015 *
2016 *	Drain the FIFO and device of any stuck data following a command
2017 *	failing to complete. In some cases this is necessary before a
2018 *	reset will recover the device.
2019 *
2020 */
2021
2022void ata_sff_drain_fifo(struct ata_queued_cmd *qc)
2023{
2024	int count;
2025	struct ata_port *ap;
2026
2027	/* We only need to flush incoming data when a command was running */
2028	if (qc == NULL || qc->dma_dir == DMA_TO_DEVICE)
2029		return;
2030
2031	ap = qc->ap;
2032	/* Drain up to 64K of data before we give up this recovery method */
2033	for (count = 0; (ap->ops->sff_check_status(ap) & ATA_DRQ)
2034						&& count < 65536; count += 2)
2035		ioread16(ap->ioaddr.data_addr);
2036
2037	if (count)
2038		ata_port_dbg(ap, "drained %d bytes to clear DRQ\n", count);
2039
2040}
2041EXPORT_SYMBOL_GPL(ata_sff_drain_fifo);
2042
2043/**
2044 *	ata_sff_error_handler - Stock error handler for SFF controller
2045 *	@ap: port to handle error for
2046 *
2047 *	Stock error handler for SFF controller.  It can handle both
2048 *	PATA and SATA controllers.  Many controllers should be able to
2049 *	use this EH as-is or with some added handling before and
2050 *	after.
2051 *
2052 *	LOCKING:
2053 *	Kernel thread context (may sleep)
2054 */
2055void ata_sff_error_handler(struct ata_port *ap)
2056{
2057	ata_reset_fn_t softreset = ap->ops->softreset;
2058	ata_reset_fn_t hardreset = ap->ops->hardreset;
2059	struct ata_queued_cmd *qc;
2060	unsigned long flags;
2061
2062	qc = __ata_qc_from_tag(ap, ap->link.active_tag);
2063	if (qc && !(qc->flags & ATA_QCFLAG_EH))
2064		qc = NULL;
2065
2066	spin_lock_irqsave(ap->lock, flags);
2067
2068	/*
2069	 * We *MUST* do FIFO draining before we issue a reset as
2070	 * several devices helpfully clear their internal state and
2071	 * will lock solid if we touch the data port post reset. Pass
2072	 * qc in case anyone wants to do different PIO/DMA recovery or
2073	 * has per command fixups
2074	 */
2075	if (ap->ops->sff_drain_fifo)
2076		ap->ops->sff_drain_fifo(qc);
2077
2078	spin_unlock_irqrestore(ap->lock, flags);
2079
2080	/* ignore built-in hardresets if SCR access is not available */
2081	if ((hardreset == sata_std_hardreset ||
2082	     hardreset == sata_sff_hardreset) && !sata_scr_valid(&ap->link))
2083		hardreset = NULL;
2084
2085	ata_do_eh(ap, ap->ops->prereset, softreset, hardreset,
2086		  ap->ops->postreset);
2087}
2088EXPORT_SYMBOL_GPL(ata_sff_error_handler);
2089
2090/**
2091 *	ata_sff_std_ports - initialize ioaddr with standard port offsets.
2092 *	@ioaddr: IO address structure to be initialized
2093 *
2094 *	Utility function which initializes data_addr, error_addr,
2095 *	feature_addr, nsect_addr, lbal_addr, lbam_addr, lbah_addr,
2096 *	device_addr, status_addr, and command_addr to standard offsets
2097 *	relative to cmd_addr.
2098 *
2099 *	Does not set ctl_addr, altstatus_addr, bmdma_addr, or scr_addr.
2100 */
2101void ata_sff_std_ports(struct ata_ioports *ioaddr)
2102{
2103	ioaddr->data_addr = ioaddr->cmd_addr + ATA_REG_DATA;
2104	ioaddr->error_addr = ioaddr->cmd_addr + ATA_REG_ERR;
2105	ioaddr->feature_addr = ioaddr->cmd_addr + ATA_REG_FEATURE;
2106	ioaddr->nsect_addr = ioaddr->cmd_addr + ATA_REG_NSECT;
2107	ioaddr->lbal_addr = ioaddr->cmd_addr + ATA_REG_LBAL;
2108	ioaddr->lbam_addr = ioaddr->cmd_addr + ATA_REG_LBAM;
2109	ioaddr->lbah_addr = ioaddr->cmd_addr + ATA_REG_LBAH;
2110	ioaddr->device_addr = ioaddr->cmd_addr + ATA_REG_DEVICE;
2111	ioaddr->status_addr = ioaddr->cmd_addr + ATA_REG_STATUS;
2112	ioaddr->command_addr = ioaddr->cmd_addr + ATA_REG_CMD;
2113}
2114EXPORT_SYMBOL_GPL(ata_sff_std_ports);
2115
2116#ifdef CONFIG_PCI
2117
2118static bool ata_resources_present(struct pci_dev *pdev, int port)
2119{
2120	int i;
2121
2122	/* Check the PCI resources for this channel are enabled */
2123	port *= 2;
2124	for (i = 0; i < 2; i++) {
2125		if (pci_resource_start(pdev, port + i) == 0 ||
2126		    pci_resource_len(pdev, port + i) == 0)
2127			return false;
2128	}
2129	return true;
2130}
2131
2132/**
2133 *	ata_pci_sff_init_host - acquire native PCI ATA resources and init host
2134 *	@host: target ATA host
2135 *
2136 *	Acquire native PCI ATA resources for @host and initialize the
2137 *	first two ports of @host accordingly.  Ports marked dummy are
2138 *	skipped and allocation failure makes the port dummy.
2139 *
2140 *	Note that native PCI resources are valid even for legacy hosts
2141 *	as we fix up pdev resources array early in boot, so this
2142 *	function can be used for both native and legacy SFF hosts.
2143 *
2144 *	LOCKING:
2145 *	Inherited from calling layer (may sleep).
2146 *
2147 *	RETURNS:
2148 *	0 if at least one port is initialized, -ENODEV if no port is
2149 *	available.
2150 */
2151int ata_pci_sff_init_host(struct ata_host *host)
2152{
2153	struct device *gdev = host->dev;
2154	struct pci_dev *pdev = to_pci_dev(gdev);
2155	unsigned int mask = 0;
2156	int i, rc;
2157
2158	/* request, iomap BARs and init port addresses accordingly */
2159	for (i = 0; i < 2; i++) {
2160		struct ata_port *ap = host->ports[i];
2161		int base = i * 2;
2162		void __iomem * const *iomap;
2163
2164		if (ata_port_is_dummy(ap))
2165			continue;
2166
2167		/* Discard disabled ports.  Some controllers show
2168		 * their unused channels this way.  Disabled ports are
2169		 * made dummy.
2170		 */
2171		if (!ata_resources_present(pdev, i)) {
2172			ap->ops = &ata_dummy_port_ops;
2173			continue;
2174		}
2175
2176		rc = pcim_iomap_regions(pdev, 0x3 << base,
2177					dev_driver_string(gdev));
2178		if (rc) {
2179			dev_warn(gdev,
2180				 "failed to request/iomap BARs for port %d (errno=%d)\n",
2181				 i, rc);
2182			if (rc == -EBUSY)
2183				pcim_pin_device(pdev);
2184			ap->ops = &ata_dummy_port_ops;
2185			continue;
2186		}
2187		host->iomap = iomap = pcim_iomap_table(pdev);
2188
2189		ap->ioaddr.cmd_addr = iomap[base];
2190		ap->ioaddr.altstatus_addr =
2191		ap->ioaddr.ctl_addr = (void __iomem *)
2192			((unsigned long)iomap[base + 1] | ATA_PCI_CTL_OFS);
2193		ata_sff_std_ports(&ap->ioaddr);
2194
2195		ata_port_desc(ap, "cmd 0x%llx ctl 0x%llx",
2196			(unsigned long long)pci_resource_start(pdev, base),
2197			(unsigned long long)pci_resource_start(pdev, base + 1));
2198
2199		mask |= 1 << i;
2200	}
2201
2202	if (!mask) {
2203		dev_err(gdev, "no available native port\n");
2204		return -ENODEV;
2205	}
2206
2207	return 0;
2208}
2209EXPORT_SYMBOL_GPL(ata_pci_sff_init_host);
2210
2211/**
2212 *	ata_pci_sff_prepare_host - helper to prepare PCI PIO-only SFF ATA host
2213 *	@pdev: target PCI device
2214 *	@ppi: array of port_info, must be enough for two ports
2215 *	@r_host: out argument for the initialized ATA host
2216 *
2217 *	Helper to allocate PIO-only SFF ATA host for @pdev, acquire
2218 *	all PCI resources and initialize it accordingly in one go.
2219 *
2220 *	LOCKING:
2221 *	Inherited from calling layer (may sleep).
2222 *
2223 *	RETURNS:
2224 *	0 on success, -errno otherwise.
2225 */
2226int ata_pci_sff_prepare_host(struct pci_dev *pdev,
2227			     const struct ata_port_info * const *ppi,
2228			     struct ata_host **r_host)
2229{
2230	struct ata_host *host;
2231	int rc;
2232
2233	if (!devres_open_group(&pdev->dev, NULL, GFP_KERNEL))
2234		return -ENOMEM;
2235
2236	host = ata_host_alloc_pinfo(&pdev->dev, ppi, 2);
2237	if (!host) {
2238		dev_err(&pdev->dev, "failed to allocate ATA host\n");
2239		rc = -ENOMEM;
2240		goto err_out;
2241	}
2242
2243	rc = ata_pci_sff_init_host(host);
2244	if (rc)
2245		goto err_out;
2246
2247	devres_remove_group(&pdev->dev, NULL);
2248	*r_host = host;
2249	return 0;
2250
2251err_out:
2252	devres_release_group(&pdev->dev, NULL);
2253	return rc;
2254}
2255EXPORT_SYMBOL_GPL(ata_pci_sff_prepare_host);
2256
2257/**
2258 *	ata_pci_sff_activate_host - start SFF host, request IRQ and register it
2259 *	@host: target SFF ATA host
2260 *	@irq_handler: irq_handler used when requesting IRQ(s)
2261 *	@sht: scsi_host_template to use when registering the host
2262 *
2263 *	This is the counterpart of ata_host_activate() for SFF ATA
2264 *	hosts.  This separate helper is necessary because SFF hosts
2265 *	use two separate interrupts in legacy mode.
2266 *
2267 *	LOCKING:
2268 *	Inherited from calling layer (may sleep).
2269 *
2270 *	RETURNS:
2271 *	0 on success, -errno otherwise.
2272 */
2273int ata_pci_sff_activate_host(struct ata_host *host,
2274			      irq_handler_t irq_handler,
2275			      const struct scsi_host_template *sht)
2276{
2277	struct device *dev = host->dev;
2278	struct pci_dev *pdev = to_pci_dev(dev);
2279	const char *drv_name = dev_driver_string(host->dev);
2280	int legacy_mode = 0, rc;
2281
2282	rc = ata_host_start(host);
2283	if (rc)
2284		return rc;
2285
2286	if ((pdev->class >> 8) == PCI_CLASS_STORAGE_IDE) {
2287		u8 tmp8, mask = 0;
2288
2289		/*
2290		 * ATA spec says we should use legacy mode when one
2291		 * port is in legacy mode, but disabled ports on some
2292		 * PCI hosts appear as fixed legacy ports, e.g SB600/700
2293		 * on which the secondary port is not wired, so
2294		 * ignore ports that are marked as 'dummy' during
2295		 * this check
2296		 */
2297		pci_read_config_byte(pdev, PCI_CLASS_PROG, &tmp8);
2298		if (!ata_port_is_dummy(host->ports[0]))
2299			mask |= (1 << 0);
2300		if (!ata_port_is_dummy(host->ports[1]))
2301			mask |= (1 << 2);
2302		if ((tmp8 & mask) != mask)
2303			legacy_mode = 1;
2304	}
2305
2306	if (!devres_open_group(dev, NULL, GFP_KERNEL))
2307		return -ENOMEM;
2308
2309	if (!legacy_mode && pdev->irq) {
2310		int i;
2311
2312		rc = devm_request_irq(dev, pdev->irq, irq_handler,
2313				      IRQF_SHARED, drv_name, host);
2314		if (rc)
2315			goto out;
2316
2317		for (i = 0; i < 2; i++) {
2318			if (ata_port_is_dummy(host->ports[i]))
2319				continue;
2320			ata_port_desc_misc(host->ports[i], pdev->irq);
2321		}
2322	} else if (legacy_mode) {
2323		if (!ata_port_is_dummy(host->ports[0])) {
2324			rc = devm_request_irq(dev, ATA_PRIMARY_IRQ(pdev),
2325					      irq_handler, IRQF_SHARED,
2326					      drv_name, host);
2327			if (rc)
2328				goto out;
2329
2330			ata_port_desc_misc(host->ports[0],
2331					   ATA_PRIMARY_IRQ(pdev));
2332		}
2333
2334		if (!ata_port_is_dummy(host->ports[1])) {
2335			rc = devm_request_irq(dev, ATA_SECONDARY_IRQ(pdev),
2336					      irq_handler, IRQF_SHARED,
2337					      drv_name, host);
2338			if (rc)
2339				goto out;
2340
2341			ata_port_desc_misc(host->ports[1],
2342					   ATA_SECONDARY_IRQ(pdev));
2343		}
2344	}
2345
2346	rc = ata_host_register(host, sht);
2347out:
2348	if (rc == 0)
2349		devres_remove_group(dev, NULL);
2350	else
2351		devres_release_group(dev, NULL);
2352
2353	return rc;
2354}
2355EXPORT_SYMBOL_GPL(ata_pci_sff_activate_host);
2356
2357static const struct ata_port_info *ata_sff_find_valid_pi(
2358					const struct ata_port_info * const *ppi)
2359{
2360	int i;
2361
2362	/* look up the first valid port_info */
2363	for (i = 0; i < 2 && ppi[i]; i++)
2364		if (ppi[i]->port_ops != &ata_dummy_port_ops)
2365			return ppi[i];
2366
2367	return NULL;
2368}
2369
2370static int ata_pci_init_one(struct pci_dev *pdev,
2371		const struct ata_port_info * const *ppi,
2372		const struct scsi_host_template *sht, void *host_priv,
2373		int hflags, bool bmdma)
2374{
2375	struct device *dev = &pdev->dev;
2376	const struct ata_port_info *pi;
2377	struct ata_host *host = NULL;
2378	int rc;
2379
2380	pi = ata_sff_find_valid_pi(ppi);
2381	if (!pi) {
2382		dev_err(&pdev->dev, "no valid port_info specified\n");
2383		return -EINVAL;
2384	}
2385
2386	if (!devres_open_group(dev, NULL, GFP_KERNEL))
2387		return -ENOMEM;
2388
2389	rc = pcim_enable_device(pdev);
2390	if (rc)
2391		goto out;
2392
2393#ifdef CONFIG_ATA_BMDMA
2394	if (bmdma)
2395		/* prepare and activate BMDMA host */
2396		rc = ata_pci_bmdma_prepare_host(pdev, ppi, &host);
2397	else
2398#endif
2399		/* prepare and activate SFF host */
2400		rc = ata_pci_sff_prepare_host(pdev, ppi, &host);
2401	if (rc)
2402		goto out;
2403	host->private_data = host_priv;
2404	host->flags |= hflags;
2405
2406#ifdef CONFIG_ATA_BMDMA
2407	if (bmdma) {
2408		pci_set_master(pdev);
2409		rc = ata_pci_sff_activate_host(host, ata_bmdma_interrupt, sht);
2410	} else
2411#endif
2412		rc = ata_pci_sff_activate_host(host, ata_sff_interrupt, sht);
2413out:
2414	if (rc == 0)
2415		devres_remove_group(&pdev->dev, NULL);
2416	else
2417		devres_release_group(&pdev->dev, NULL);
2418
2419	return rc;
2420}
2421
2422/**
2423 *	ata_pci_sff_init_one - Initialize/register PIO-only PCI IDE controller
2424 *	@pdev: Controller to be initialized
2425 *	@ppi: array of port_info, must be enough for two ports
2426 *	@sht: scsi_host_template to use when registering the host
2427 *	@host_priv: host private_data
2428 *	@hflag: host flags
2429 *
2430 *	This is a helper function which can be called from a driver's
2431 *	xxx_init_one() probe function if the hardware uses traditional
2432 *	IDE taskfile registers and is PIO only.
2433 *
2434 *	ASSUMPTION:
2435 *	Nobody makes a single channel controller that appears solely as
2436 *	the secondary legacy port on PCI.
2437 *
2438 *	LOCKING:
2439 *	Inherited from PCI layer (may sleep).
2440 *
2441 *	RETURNS:
2442 *	Zero on success, negative on errno-based value on error.
2443 */
2444int ata_pci_sff_init_one(struct pci_dev *pdev,
2445		 const struct ata_port_info * const *ppi,
2446		 const struct scsi_host_template *sht, void *host_priv, int hflag)
2447{
2448	return ata_pci_init_one(pdev, ppi, sht, host_priv, hflag, 0);
2449}
2450EXPORT_SYMBOL_GPL(ata_pci_sff_init_one);
2451
2452#endif /* CONFIG_PCI */
2453
2454/*
2455 *	BMDMA support
2456 */
2457
2458#ifdef CONFIG_ATA_BMDMA
2459
2460const struct ata_port_operations ata_bmdma_port_ops = {
2461	.inherits		= &ata_sff_port_ops,
2462
2463	.error_handler		= ata_bmdma_error_handler,
2464	.post_internal_cmd	= ata_bmdma_post_internal_cmd,
2465
2466	.qc_prep		= ata_bmdma_qc_prep,
2467	.qc_issue		= ata_bmdma_qc_issue,
2468
2469	.sff_irq_clear		= ata_bmdma_irq_clear,
2470	.bmdma_setup		= ata_bmdma_setup,
2471	.bmdma_start		= ata_bmdma_start,
2472	.bmdma_stop		= ata_bmdma_stop,
2473	.bmdma_status		= ata_bmdma_status,
2474
2475	.port_start		= ata_bmdma_port_start,
2476};
2477EXPORT_SYMBOL_GPL(ata_bmdma_port_ops);
2478
2479const struct ata_port_operations ata_bmdma32_port_ops = {
2480	.inherits		= &ata_bmdma_port_ops,
2481
2482	.sff_data_xfer		= ata_sff_data_xfer32,
2483	.port_start		= ata_bmdma_port_start32,
2484};
2485EXPORT_SYMBOL_GPL(ata_bmdma32_port_ops);
2486
2487/**
2488 *	ata_bmdma_fill_sg - Fill PCI IDE PRD table
2489 *	@qc: Metadata associated with taskfile to be transferred
2490 *
2491 *	Fill PCI IDE PRD (scatter-gather) table with segments
2492 *	associated with the current disk command.
2493 *
2494 *	LOCKING:
2495 *	spin_lock_irqsave(host lock)
2496 *
2497 */
2498static void ata_bmdma_fill_sg(struct ata_queued_cmd *qc)
2499{
2500	struct ata_port *ap = qc->ap;
2501	struct ata_bmdma_prd *prd = ap->bmdma_prd;
2502	struct scatterlist *sg;
2503	unsigned int si, pi;
2504
2505	pi = 0;
2506	for_each_sg(qc->sg, sg, qc->n_elem, si) {
2507		u32 addr, offset;
2508		u32 sg_len, len;
2509
2510		/* determine if physical DMA addr spans 64K boundary.
2511		 * Note h/w doesn't support 64-bit, so we unconditionally
2512		 * truncate dma_addr_t to u32.
2513		 */
2514		addr = (u32) sg_dma_address(sg);
2515		sg_len = sg_dma_len(sg);
2516
2517		while (sg_len) {
2518			offset = addr & 0xffff;
2519			len = sg_len;
2520			if ((offset + sg_len) > 0x10000)
2521				len = 0x10000 - offset;
2522
2523			prd[pi].addr = cpu_to_le32(addr);
2524			prd[pi].flags_len = cpu_to_le32(len & 0xffff);
2525
2526			pi++;
2527			sg_len -= len;
2528			addr += len;
2529		}
2530	}
2531
2532	prd[pi - 1].flags_len |= cpu_to_le32(ATA_PRD_EOT);
2533}
2534
2535/**
2536 *	ata_bmdma_fill_sg_dumb - Fill PCI IDE PRD table
2537 *	@qc: Metadata associated with taskfile to be transferred
2538 *
2539 *	Fill PCI IDE PRD (scatter-gather) table with segments
2540 *	associated with the current disk command. Perform the fill
2541 *	so that we avoid writing any length 64K records for
2542 *	controllers that don't follow the spec.
2543 *
2544 *	LOCKING:
2545 *	spin_lock_irqsave(host lock)
2546 *
2547 */
2548static void ata_bmdma_fill_sg_dumb(struct ata_queued_cmd *qc)
2549{
2550	struct ata_port *ap = qc->ap;
2551	struct ata_bmdma_prd *prd = ap->bmdma_prd;
2552	struct scatterlist *sg;
2553	unsigned int si, pi;
2554
2555	pi = 0;
2556	for_each_sg(qc->sg, sg, qc->n_elem, si) {
2557		u32 addr, offset;
2558		u32 sg_len, len, blen;
2559
2560		/* determine if physical DMA addr spans 64K boundary.
2561		 * Note h/w doesn't support 64-bit, so we unconditionally
2562		 * truncate dma_addr_t to u32.
2563		 */
2564		addr = (u32) sg_dma_address(sg);
2565		sg_len = sg_dma_len(sg);
2566
2567		while (sg_len) {
2568			offset = addr & 0xffff;
2569			len = sg_len;
2570			if ((offset + sg_len) > 0x10000)
2571				len = 0x10000 - offset;
2572
2573			blen = len & 0xffff;
2574			prd[pi].addr = cpu_to_le32(addr);
2575			if (blen == 0) {
2576				/* Some PATA chipsets like the CS5530 can't
2577				   cope with 0x0000 meaning 64K as the spec
2578				   says */
2579				prd[pi].flags_len = cpu_to_le32(0x8000);
2580				blen = 0x8000;
2581				prd[++pi].addr = cpu_to_le32(addr + 0x8000);
2582			}
2583			prd[pi].flags_len = cpu_to_le32(blen);
2584
2585			pi++;
2586			sg_len -= len;
2587			addr += len;
2588		}
2589	}
2590
2591	prd[pi - 1].flags_len |= cpu_to_le32(ATA_PRD_EOT);
2592}
2593
2594/**
2595 *	ata_bmdma_qc_prep - Prepare taskfile for submission
2596 *	@qc: Metadata associated with taskfile to be prepared
2597 *
2598 *	Prepare ATA taskfile for submission.
2599 *
2600 *	LOCKING:
2601 *	spin_lock_irqsave(host lock)
2602 */
2603enum ata_completion_errors ata_bmdma_qc_prep(struct ata_queued_cmd *qc)
2604{
2605	if (!(qc->flags & ATA_QCFLAG_DMAMAP))
2606		return AC_ERR_OK;
2607
2608	ata_bmdma_fill_sg(qc);
2609
2610	return AC_ERR_OK;
2611}
2612EXPORT_SYMBOL_GPL(ata_bmdma_qc_prep);
2613
2614/**
2615 *	ata_bmdma_dumb_qc_prep - Prepare taskfile for submission
2616 *	@qc: Metadata associated with taskfile to be prepared
2617 *
2618 *	Prepare ATA taskfile for submission.
2619 *
2620 *	LOCKING:
2621 *	spin_lock_irqsave(host lock)
2622 */
2623enum ata_completion_errors ata_bmdma_dumb_qc_prep(struct ata_queued_cmd *qc)
2624{
2625	if (!(qc->flags & ATA_QCFLAG_DMAMAP))
2626		return AC_ERR_OK;
2627
2628	ata_bmdma_fill_sg_dumb(qc);
2629
2630	return AC_ERR_OK;
2631}
2632EXPORT_SYMBOL_GPL(ata_bmdma_dumb_qc_prep);
2633
2634/**
2635 *	ata_bmdma_qc_issue - issue taskfile to a BMDMA controller
2636 *	@qc: command to issue to device
2637 *
2638 *	This function issues a PIO, NODATA or DMA command to a
2639 *	SFF/BMDMA controller.  PIO and NODATA are handled by
2640 *	ata_sff_qc_issue().
2641 *
2642 *	LOCKING:
2643 *	spin_lock_irqsave(host lock)
2644 *
2645 *	RETURNS:
2646 *	Zero on success, AC_ERR_* mask on failure
2647 */
2648unsigned int ata_bmdma_qc_issue(struct ata_queued_cmd *qc)
2649{
2650	struct ata_port *ap = qc->ap;
2651	struct ata_link *link = qc->dev->link;
2652
2653	/* defer PIO handling to sff_qc_issue */
2654	if (!ata_is_dma(qc->tf.protocol))
2655		return ata_sff_qc_issue(qc);
2656
2657	/* select the device */
2658	ata_dev_select(ap, qc->dev->devno, 1, 0);
2659
2660	/* start the command */
2661	switch (qc->tf.protocol) {
2662	case ATA_PROT_DMA:
2663		WARN_ON_ONCE(qc->tf.flags & ATA_TFLAG_POLLING);
2664
2665		trace_ata_tf_load(ap, &qc->tf);
2666		ap->ops->sff_tf_load(ap, &qc->tf);  /* load tf registers */
2667		trace_ata_bmdma_setup(ap, &qc->tf, qc->tag);
2668		ap->ops->bmdma_setup(qc);	    /* set up bmdma */
2669		trace_ata_bmdma_start(ap, &qc->tf, qc->tag);
2670		ap->ops->bmdma_start(qc);	    /* initiate bmdma */
2671		ap->hsm_task_state = HSM_ST_LAST;
2672		break;
2673
2674	case ATAPI_PROT_DMA:
2675		WARN_ON_ONCE(qc->tf.flags & ATA_TFLAG_POLLING);
2676
2677		trace_ata_tf_load(ap, &qc->tf);
2678		ap->ops->sff_tf_load(ap, &qc->tf);  /* load tf registers */
2679		trace_ata_bmdma_setup(ap, &qc->tf, qc->tag);
2680		ap->ops->bmdma_setup(qc);	    /* set up bmdma */
2681		ap->hsm_task_state = HSM_ST_FIRST;
2682
2683		/* send cdb by polling if no cdb interrupt */
2684		if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
2685			ata_sff_queue_pio_task(link, 0);
2686		break;
2687
2688	default:
2689		WARN_ON(1);
2690		return AC_ERR_SYSTEM;
2691	}
2692
2693	return 0;
2694}
2695EXPORT_SYMBOL_GPL(ata_bmdma_qc_issue);
2696
2697/**
2698 *	ata_bmdma_port_intr - Handle BMDMA port interrupt
2699 *	@ap: Port on which interrupt arrived (possibly...)
2700 *	@qc: Taskfile currently active in engine
2701 *
2702 *	Handle port interrupt for given queued command.
2703 *
2704 *	LOCKING:
2705 *	spin_lock_irqsave(host lock)
2706 *
2707 *	RETURNS:
2708 *	One if interrupt was handled, zero if not (shared irq).
2709 */
2710unsigned int ata_bmdma_port_intr(struct ata_port *ap, struct ata_queued_cmd *qc)
2711{
2712	struct ata_eh_info *ehi = &ap->link.eh_info;
2713	u8 host_stat = 0;
2714	bool bmdma_stopped = false;
2715	unsigned int handled;
2716
2717	if (ap->hsm_task_state == HSM_ST_LAST && ata_is_dma(qc->tf.protocol)) {
2718		/* check status of DMA engine */
2719		host_stat = ap->ops->bmdma_status(ap);
2720		trace_ata_bmdma_status(ap, host_stat);
2721
2722		/* if it's not our irq... */
2723		if (!(host_stat & ATA_DMA_INTR))
2724			return ata_sff_idle_irq(ap);
2725
2726		/* before we do anything else, clear DMA-Start bit */
2727		trace_ata_bmdma_stop(ap, &qc->tf, qc->tag);
2728		ap->ops->bmdma_stop(qc);
2729		bmdma_stopped = true;
2730
2731		if (unlikely(host_stat & ATA_DMA_ERR)) {
2732			/* error when transferring data to/from memory */
2733			qc->err_mask |= AC_ERR_HOST_BUS;
2734			ap->hsm_task_state = HSM_ST_ERR;
2735		}
2736	}
2737
2738	handled = __ata_sff_port_intr(ap, qc, bmdma_stopped);
2739
2740	if (unlikely(qc->err_mask) && ata_is_dma(qc->tf.protocol))
2741		ata_ehi_push_desc(ehi, "BMDMA stat 0x%x", host_stat);
2742
2743	return handled;
2744}
2745EXPORT_SYMBOL_GPL(ata_bmdma_port_intr);
2746
2747/**
2748 *	ata_bmdma_interrupt - Default BMDMA ATA host interrupt handler
2749 *	@irq: irq line (unused)
2750 *	@dev_instance: pointer to our ata_host information structure
2751 *
2752 *	Default interrupt handler for PCI IDE devices.  Calls
2753 *	ata_bmdma_port_intr() for each port that is not disabled.
2754 *
2755 *	LOCKING:
2756 *	Obtains host lock during operation.
2757 *
2758 *	RETURNS:
2759 *	IRQ_NONE or IRQ_HANDLED.
2760 */
2761irqreturn_t ata_bmdma_interrupt(int irq, void *dev_instance)
2762{
2763	return __ata_sff_interrupt(irq, dev_instance, ata_bmdma_port_intr);
2764}
2765EXPORT_SYMBOL_GPL(ata_bmdma_interrupt);
2766
2767/**
2768 *	ata_bmdma_error_handler - Stock error handler for BMDMA controller
2769 *	@ap: port to handle error for
2770 *
2771 *	Stock error handler for BMDMA controller.  It can handle both
2772 *	PATA and SATA controllers.  Most BMDMA controllers should be
2773 *	able to use this EH as-is or with some added handling before
2774 *	and after.
2775 *
2776 *	LOCKING:
2777 *	Kernel thread context (may sleep)
2778 */
2779void ata_bmdma_error_handler(struct ata_port *ap)
2780{
2781	struct ata_queued_cmd *qc;
2782	unsigned long flags;
2783	bool thaw = false;
2784
2785	qc = __ata_qc_from_tag(ap, ap->link.active_tag);
2786	if (qc && !(qc->flags & ATA_QCFLAG_EH))
2787		qc = NULL;
2788
2789	/* reset PIO HSM and stop DMA engine */
2790	spin_lock_irqsave(ap->lock, flags);
2791
2792	if (qc && ata_is_dma(qc->tf.protocol)) {
2793		u8 host_stat;
2794
2795		host_stat = ap->ops->bmdma_status(ap);
2796		trace_ata_bmdma_status(ap, host_stat);
2797
2798		/* BMDMA controllers indicate host bus error by
2799		 * setting DMA_ERR bit and timing out.  As it wasn't
2800		 * really a timeout event, adjust error mask and
2801		 * cancel frozen state.
2802		 */
2803		if (qc->err_mask == AC_ERR_TIMEOUT && (host_stat & ATA_DMA_ERR)) {
2804			qc->err_mask = AC_ERR_HOST_BUS;
2805			thaw = true;
2806		}
2807
2808		trace_ata_bmdma_stop(ap, &qc->tf, qc->tag);
2809		ap->ops->bmdma_stop(qc);
2810
2811		/* if we're gonna thaw, make sure IRQ is clear */
2812		if (thaw) {
2813			ap->ops->sff_check_status(ap);
2814			if (ap->ops->sff_irq_clear)
2815				ap->ops->sff_irq_clear(ap);
2816		}
2817	}
2818
2819	spin_unlock_irqrestore(ap->lock, flags);
2820
2821	if (thaw)
2822		ata_eh_thaw_port(ap);
2823
2824	ata_sff_error_handler(ap);
2825}
2826EXPORT_SYMBOL_GPL(ata_bmdma_error_handler);
2827
2828/**
2829 *	ata_bmdma_post_internal_cmd - Stock post_internal_cmd for BMDMA
2830 *	@qc: internal command to clean up
2831 *
2832 *	LOCKING:
2833 *	Kernel thread context (may sleep)
2834 */
2835void ata_bmdma_post_internal_cmd(struct ata_queued_cmd *qc)
2836{
2837	struct ata_port *ap = qc->ap;
2838	unsigned long flags;
2839
2840	if (ata_is_dma(qc->tf.protocol)) {
2841		spin_lock_irqsave(ap->lock, flags);
2842		trace_ata_bmdma_stop(ap, &qc->tf, qc->tag);
2843		ap->ops->bmdma_stop(qc);
2844		spin_unlock_irqrestore(ap->lock, flags);
2845	}
2846}
2847EXPORT_SYMBOL_GPL(ata_bmdma_post_internal_cmd);
2848
2849/**
2850 *	ata_bmdma_irq_clear - Clear PCI IDE BMDMA interrupt.
2851 *	@ap: Port associated with this ATA transaction.
2852 *
2853 *	Clear interrupt and error flags in DMA status register.
2854 *
2855 *	May be used as the irq_clear() entry in ata_port_operations.
2856 *
2857 *	LOCKING:
2858 *	spin_lock_irqsave(host lock)
2859 */
2860void ata_bmdma_irq_clear(struct ata_port *ap)
2861{
2862	void __iomem *mmio = ap->ioaddr.bmdma_addr;
2863
2864	if (!mmio)
2865		return;
2866
2867	iowrite8(ioread8(mmio + ATA_DMA_STATUS), mmio + ATA_DMA_STATUS);
2868}
2869EXPORT_SYMBOL_GPL(ata_bmdma_irq_clear);
2870
2871/**
2872 *	ata_bmdma_setup - Set up PCI IDE BMDMA transaction
2873 *	@qc: Info associated with this ATA transaction.
2874 *
2875 *	LOCKING:
2876 *	spin_lock_irqsave(host lock)
2877 */
2878void ata_bmdma_setup(struct ata_queued_cmd *qc)
2879{
2880	struct ata_port *ap = qc->ap;
2881	unsigned int rw = (qc->tf.flags & ATA_TFLAG_WRITE);
2882	u8 dmactl;
2883
2884	/* load PRD table addr. */
2885	mb();	/* make sure PRD table writes are visible to controller */
2886	iowrite32(ap->bmdma_prd_dma, ap->ioaddr.bmdma_addr + ATA_DMA_TABLE_OFS);
2887
2888	/* specify data direction, triple-check start bit is clear */
2889	dmactl = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
2890	dmactl &= ~(ATA_DMA_WR | ATA_DMA_START);
2891	if (!rw)
2892		dmactl |= ATA_DMA_WR;
2893	iowrite8(dmactl, ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
2894
2895	/* issue r/w command */
2896	ap->ops->sff_exec_command(ap, &qc->tf);
2897}
2898EXPORT_SYMBOL_GPL(ata_bmdma_setup);
2899
2900/**
2901 *	ata_bmdma_start - Start a PCI IDE BMDMA transaction
2902 *	@qc: Info associated with this ATA transaction.
2903 *
2904 *	LOCKING:
2905 *	spin_lock_irqsave(host lock)
2906 */
2907void ata_bmdma_start(struct ata_queued_cmd *qc)
2908{
2909	struct ata_port *ap = qc->ap;
2910	u8 dmactl;
2911
2912	/* start host DMA transaction */
2913	dmactl = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
2914	iowrite8(dmactl | ATA_DMA_START, ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
2915
2916	/* Strictly, one may wish to issue an ioread8() here, to
2917	 * flush the mmio write.  However, control also passes
2918	 * to the hardware at this point, and it will interrupt
2919	 * us when we are to resume control.  So, in effect,
2920	 * we don't care when the mmio write flushes.
2921	 * Further, a read of the DMA status register _immediately_
2922	 * following the write may not be what certain flaky hardware
2923	 * is expected, so I think it is best to not add a readb()
2924	 * without first all the MMIO ATA cards/mobos.
2925	 * Or maybe I'm just being paranoid.
2926	 *
2927	 * FIXME: The posting of this write means I/O starts are
2928	 * unnecessarily delayed for MMIO
2929	 */
2930}
2931EXPORT_SYMBOL_GPL(ata_bmdma_start);
2932
2933/**
2934 *	ata_bmdma_stop - Stop PCI IDE BMDMA transfer
2935 *	@qc: Command we are ending DMA for
2936 *
2937 *	Clears the ATA_DMA_START flag in the dma control register
2938 *
2939 *	May be used as the bmdma_stop() entry in ata_port_operations.
2940 *
2941 *	LOCKING:
2942 *	spin_lock_irqsave(host lock)
2943 */
2944void ata_bmdma_stop(struct ata_queued_cmd *qc)
2945{
2946	struct ata_port *ap = qc->ap;
2947	void __iomem *mmio = ap->ioaddr.bmdma_addr;
2948
2949	/* clear start/stop bit */
2950	iowrite8(ioread8(mmio + ATA_DMA_CMD) & ~ATA_DMA_START,
2951		 mmio + ATA_DMA_CMD);
2952
2953	/* one-PIO-cycle guaranteed wait, per spec, for HDMA1:0 transition */
2954	ata_sff_dma_pause(ap);
2955}
2956EXPORT_SYMBOL_GPL(ata_bmdma_stop);
2957
2958/**
2959 *	ata_bmdma_status - Read PCI IDE BMDMA status
2960 *	@ap: Port associated with this ATA transaction.
2961 *
2962 *	Read and return BMDMA status register.
2963 *
2964 *	May be used as the bmdma_status() entry in ata_port_operations.
2965 *
2966 *	LOCKING:
2967 *	spin_lock_irqsave(host lock)
2968 */
2969u8 ata_bmdma_status(struct ata_port *ap)
2970{
2971	return ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);
2972}
2973EXPORT_SYMBOL_GPL(ata_bmdma_status);
2974
2975
2976/**
2977 *	ata_bmdma_port_start - Set port up for bmdma.
2978 *	@ap: Port to initialize
2979 *
2980 *	Called just after data structures for each port are
2981 *	initialized.  Allocates space for PRD table.
2982 *
2983 *	May be used as the port_start() entry in ata_port_operations.
2984 *
2985 *	LOCKING:
2986 *	Inherited from caller.
2987 */
2988int ata_bmdma_port_start(struct ata_port *ap)
2989{
2990	if (ap->mwdma_mask || ap->udma_mask) {
2991		ap->bmdma_prd =
2992			dmam_alloc_coherent(ap->host->dev, ATA_PRD_TBL_SZ,
2993					    &ap->bmdma_prd_dma, GFP_KERNEL);
2994		if (!ap->bmdma_prd)
2995			return -ENOMEM;
2996	}
2997
2998	return 0;
2999}
3000EXPORT_SYMBOL_GPL(ata_bmdma_port_start);
3001
3002/**
3003 *	ata_bmdma_port_start32 - Set port up for dma.
3004 *	@ap: Port to initialize
3005 *
3006 *	Called just after data structures for each port are
3007 *	initialized.  Enables 32bit PIO and allocates space for PRD
3008 *	table.
3009 *
3010 *	May be used as the port_start() entry in ata_port_operations for
3011 *	devices that are capable of 32bit PIO.
3012 *
3013 *	LOCKING:
3014 *	Inherited from caller.
3015 */
3016int ata_bmdma_port_start32(struct ata_port *ap)
3017{
3018	ap->pflags |= ATA_PFLAG_PIO32 | ATA_PFLAG_PIO32CHANGE;
3019	return ata_bmdma_port_start(ap);
3020}
3021EXPORT_SYMBOL_GPL(ata_bmdma_port_start32);
3022
3023#ifdef CONFIG_PCI
3024
3025/**
3026 *	ata_pci_bmdma_clear_simplex -	attempt to kick device out of simplex
3027 *	@pdev: PCI device
3028 *
3029 *	Some PCI ATA devices report simplex mode but in fact can be told to
3030 *	enter non simplex mode. This implements the necessary logic to
3031 *	perform the task on such devices. Calling it on other devices will
3032 *	have -undefined- behaviour.
3033 */
3034int ata_pci_bmdma_clear_simplex(struct pci_dev *pdev)
3035{
3036#ifdef CONFIG_HAS_IOPORT
3037	unsigned long bmdma = pci_resource_start(pdev, 4);
3038	u8 simplex;
3039
3040	if (bmdma == 0)
3041		return -ENOENT;
3042
3043	simplex = inb(bmdma + 0x02);
3044	outb(simplex & 0x60, bmdma + 0x02);
3045	simplex = inb(bmdma + 0x02);
3046	if (simplex & 0x80)
3047		return -EOPNOTSUPP;
3048	return 0;
3049#else
3050	return -ENOENT;
3051#endif /* CONFIG_HAS_IOPORT */
3052}
3053EXPORT_SYMBOL_GPL(ata_pci_bmdma_clear_simplex);
3054
3055static void ata_bmdma_nodma(struct ata_host *host, const char *reason)
3056{
3057	int i;
3058
3059	dev_err(host->dev, "BMDMA: %s, falling back to PIO\n", reason);
3060
3061	for (i = 0; i < 2; i++) {
3062		host->ports[i]->mwdma_mask = 0;
3063		host->ports[i]->udma_mask = 0;
3064	}
3065}
3066
3067/**
3068 *	ata_pci_bmdma_init - acquire PCI BMDMA resources and init ATA host
3069 *	@host: target ATA host
3070 *
3071 *	Acquire PCI BMDMA resources and initialize @host accordingly.
3072 *
3073 *	LOCKING:
3074 *	Inherited from calling layer (may sleep).
3075 */
3076void ata_pci_bmdma_init(struct ata_host *host)
3077{
3078	struct device *gdev = host->dev;
3079	struct pci_dev *pdev = to_pci_dev(gdev);
3080	int i, rc;
3081
3082	/* No BAR4 allocation: No DMA */
3083	if (pci_resource_start(pdev, 4) == 0) {
3084		ata_bmdma_nodma(host, "BAR4 is zero");
3085		return;
3086	}
3087
3088	/*
3089	 * Some controllers require BMDMA region to be initialized
3090	 * even if DMA is not in use to clear IRQ status via
3091	 * ->sff_irq_clear method.  Try to initialize bmdma_addr
3092	 * regardless of dma masks.
3093	 */
3094	rc = dma_set_mask_and_coherent(&pdev->dev, ATA_DMA_MASK);
3095	if (rc)
3096		ata_bmdma_nodma(host, "failed to set dma mask");
3097
3098	/* request and iomap DMA region */
3099	rc = pcim_iomap_regions(pdev, 1 << 4, dev_driver_string(gdev));
3100	if (rc) {
3101		ata_bmdma_nodma(host, "failed to request/iomap BAR4");
3102		return;
3103	}
3104	host->iomap = pcim_iomap_table(pdev);
3105
3106	for (i = 0; i < 2; i++) {
3107		struct ata_port *ap = host->ports[i];
3108		void __iomem *bmdma = host->iomap[4] + 8 * i;
3109
3110		if (ata_port_is_dummy(ap))
3111			continue;
3112
3113		ap->ioaddr.bmdma_addr = bmdma;
3114		if ((!(ap->flags & ATA_FLAG_IGN_SIMPLEX)) &&
3115		    (ioread8(bmdma + 2) & 0x80))
3116			host->flags |= ATA_HOST_SIMPLEX;
3117
3118		ata_port_desc(ap, "bmdma 0x%llx",
3119		    (unsigned long long)pci_resource_start(pdev, 4) + 8 * i);
3120	}
3121}
3122EXPORT_SYMBOL_GPL(ata_pci_bmdma_init);
3123
3124/**
3125 *	ata_pci_bmdma_prepare_host - helper to prepare PCI BMDMA ATA host
3126 *	@pdev: target PCI device
3127 *	@ppi: array of port_info, must be enough for two ports
3128 *	@r_host: out argument for the initialized ATA host
3129 *
3130 *	Helper to allocate BMDMA ATA host for @pdev, acquire all PCI
3131 *	resources and initialize it accordingly in one go.
3132 *
3133 *	LOCKING:
3134 *	Inherited from calling layer (may sleep).
3135 *
3136 *	RETURNS:
3137 *	0 on success, -errno otherwise.
3138 */
3139int ata_pci_bmdma_prepare_host(struct pci_dev *pdev,
3140			       const struct ata_port_info * const * ppi,
3141			       struct ata_host **r_host)
3142{
3143	int rc;
3144
3145	rc = ata_pci_sff_prepare_host(pdev, ppi, r_host);
3146	if (rc)
3147		return rc;
3148
3149	ata_pci_bmdma_init(*r_host);
3150	return 0;
3151}
3152EXPORT_SYMBOL_GPL(ata_pci_bmdma_prepare_host);
3153
3154/**
3155 *	ata_pci_bmdma_init_one - Initialize/register BMDMA PCI IDE controller
3156 *	@pdev: Controller to be initialized
3157 *	@ppi: array of port_info, must be enough for two ports
3158 *	@sht: scsi_host_template to use when registering the host
3159 *	@host_priv: host private_data
3160 *	@hflags: host flags
3161 *
3162 *	This function is similar to ata_pci_sff_init_one() but also
3163 *	takes care of BMDMA initialization.
3164 *
3165 *	LOCKING:
3166 *	Inherited from PCI layer (may sleep).
3167 *
3168 *	RETURNS:
3169 *	Zero on success, negative on errno-based value on error.
3170 */
3171int ata_pci_bmdma_init_one(struct pci_dev *pdev,
3172			   const struct ata_port_info * const * ppi,
3173			   const struct scsi_host_template *sht, void *host_priv,
3174			   int hflags)
3175{
3176	return ata_pci_init_one(pdev, ppi, sht, host_priv, hflags, 1);
3177}
3178EXPORT_SYMBOL_GPL(ata_pci_bmdma_init_one);
3179
3180#endif /* CONFIG_PCI */
3181#endif /* CONFIG_ATA_BMDMA */
3182
3183/**
3184 *	ata_sff_port_init - Initialize SFF/BMDMA ATA port
3185 *	@ap: Port to initialize
3186 *
3187 *	Called on port allocation to initialize SFF/BMDMA specific
3188 *	fields.
3189 *
3190 *	LOCKING:
3191 *	None.
3192 */
3193void ata_sff_port_init(struct ata_port *ap)
3194{
3195	INIT_DELAYED_WORK(&ap->sff_pio_task, ata_sff_pio_task);
3196	ap->ctl = ATA_DEVCTL_OBS;
3197	ap->last_ctl = 0xFF;
3198}
3199
3200int __init ata_sff_init(void)
3201{
3202	ata_sff_wq = alloc_workqueue("ata_sff", WQ_MEM_RECLAIM, WQ_MAX_ACTIVE);
3203	if (!ata_sff_wq)
3204		return -ENOMEM;
3205
3206	return 0;
3207}
3208
3209void ata_sff_exit(void)
3210{
3211	destroy_workqueue(ata_sff_wq);
3212}
v6.2
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  libata-sff.c - helper library for PCI IDE BMDMA
   4 *
   5 *  Copyright 2003-2006 Red Hat, Inc.  All rights reserved.
   6 *  Copyright 2003-2006 Jeff Garzik
   7 *
   8 *  libata documentation is available via 'make {ps|pdf}docs',
   9 *  as Documentation/driver-api/libata.rst
  10 *
  11 *  Hardware documentation available from http://www.t13.org/ and
  12 *  http://www.sata-io.org/
  13 */
  14
  15#include <linux/kernel.h>
  16#include <linux/gfp.h>
  17#include <linux/pci.h>
  18#include <linux/module.h>
  19#include <linux/libata.h>
  20#include <linux/highmem.h>
  21#include <trace/events/libata.h>
  22#include "libata.h"
  23
  24static struct workqueue_struct *ata_sff_wq;
  25
  26const struct ata_port_operations ata_sff_port_ops = {
  27	.inherits		= &ata_base_port_ops,
  28
  29	.qc_prep		= ata_noop_qc_prep,
  30	.qc_issue		= ata_sff_qc_issue,
  31	.qc_fill_rtf		= ata_sff_qc_fill_rtf,
  32
  33	.freeze			= ata_sff_freeze,
  34	.thaw			= ata_sff_thaw,
  35	.prereset		= ata_sff_prereset,
  36	.softreset		= ata_sff_softreset,
  37	.hardreset		= sata_sff_hardreset,
  38	.postreset		= ata_sff_postreset,
  39	.error_handler		= ata_sff_error_handler,
  40
  41	.sff_dev_select		= ata_sff_dev_select,
  42	.sff_check_status	= ata_sff_check_status,
  43	.sff_tf_load		= ata_sff_tf_load,
  44	.sff_tf_read		= ata_sff_tf_read,
  45	.sff_exec_command	= ata_sff_exec_command,
  46	.sff_data_xfer		= ata_sff_data_xfer,
  47	.sff_drain_fifo		= ata_sff_drain_fifo,
  48
  49	.lost_interrupt		= ata_sff_lost_interrupt,
  50};
  51EXPORT_SYMBOL_GPL(ata_sff_port_ops);
  52
  53/**
  54 *	ata_sff_check_status - Read device status reg & clear interrupt
  55 *	@ap: port where the device is
  56 *
  57 *	Reads ATA taskfile status register for currently-selected device
  58 *	and return its value. This also clears pending interrupts
  59 *      from this device
  60 *
  61 *	LOCKING:
  62 *	Inherited from caller.
  63 */
  64u8 ata_sff_check_status(struct ata_port *ap)
  65{
  66	return ioread8(ap->ioaddr.status_addr);
  67}
  68EXPORT_SYMBOL_GPL(ata_sff_check_status);
  69
  70/**
  71 *	ata_sff_altstatus - Read device alternate status reg
  72 *	@ap: port where the device is
  73 *	@status: pointer to a status value
  74 *
  75 *	Reads ATA alternate status register for currently-selected device
  76 *	and return its value.
  77 *
  78 *	RETURN:
  79 *	true if the register exists, false if not.
  80 *
  81 *	LOCKING:
  82 *	Inherited from caller.
  83 */
  84static bool ata_sff_altstatus(struct ata_port *ap, u8 *status)
  85{
  86	u8 tmp;
  87
  88	if (ap->ops->sff_check_altstatus) {
  89		tmp = ap->ops->sff_check_altstatus(ap);
  90		goto read;
  91	}
  92	if (ap->ioaddr.altstatus_addr) {
  93		tmp = ioread8(ap->ioaddr.altstatus_addr);
  94		goto read;
  95	}
  96	return false;
  97
  98read:
  99	if (status)
 100		*status = tmp;
 101	return true;
 102}
 103
 104/**
 105 *	ata_sff_irq_status - Check if the device is busy
 106 *	@ap: port where the device is
 107 *
 108 *	Determine if the port is currently busy. Uses altstatus
 109 *	if available in order to avoid clearing shared IRQ status
 110 *	when finding an IRQ source. Non ctl capable devices don't
 111 *	share interrupt lines fortunately for us.
 112 *
 113 *	LOCKING:
 114 *	Inherited from caller.
 115 */
 116static u8 ata_sff_irq_status(struct ata_port *ap)
 117{
 118	u8 status;
 119
 120	/* Not us: We are busy */
 121	if (ata_sff_altstatus(ap, &status) && (status & ATA_BUSY))
 122		return status;
 123	/* Clear INTRQ latch */
 124	status = ap->ops->sff_check_status(ap);
 125	return status;
 126}
 127
 128/**
 129 *	ata_sff_sync - Flush writes
 130 *	@ap: Port to wait for.
 131 *
 132 *	CAUTION:
 133 *	If we have an mmio device with no ctl and no altstatus
 134 *	method this will fail. No such devices are known to exist.
 135 *
 136 *	LOCKING:
 137 *	Inherited from caller.
 138 */
 139
 140static void ata_sff_sync(struct ata_port *ap)
 141{
 142	ata_sff_altstatus(ap, NULL);
 143}
 144
 145/**
 146 *	ata_sff_pause		-	Flush writes and wait 400nS
 147 *	@ap: Port to pause for.
 148 *
 149 *	CAUTION:
 150 *	If we have an mmio device with no ctl and no altstatus
 151 *	method this will fail. No such devices are known to exist.
 152 *
 153 *	LOCKING:
 154 *	Inherited from caller.
 155 */
 156
 157void ata_sff_pause(struct ata_port *ap)
 158{
 159	ata_sff_sync(ap);
 160	ndelay(400);
 161}
 162EXPORT_SYMBOL_GPL(ata_sff_pause);
 163
 164/**
 165 *	ata_sff_dma_pause	-	Pause before commencing DMA
 166 *	@ap: Port to pause for.
 167 *
 168 *	Perform I/O fencing and ensure sufficient cycle delays occur
 169 *	for the HDMA1:0 transition
 170 */
 171
 172void ata_sff_dma_pause(struct ata_port *ap)
 173{
 174	/*
 175	 * An altstatus read will cause the needed delay without
 176	 * messing up the IRQ status
 177	 */
 178	if (ata_sff_altstatus(ap, NULL))
 179		return;
 180	/* There are no DMA controllers without ctl. BUG here to ensure
 181	   we never violate the HDMA1:0 transition timing and risk
 182	   corruption. */
 183	BUG();
 184}
 185EXPORT_SYMBOL_GPL(ata_sff_dma_pause);
 186
 187static int ata_sff_check_ready(struct ata_link *link)
 188{
 189	u8 status = link->ap->ops->sff_check_status(link->ap);
 190
 191	return ata_check_ready(status);
 192}
 193
 194/**
 195 *	ata_sff_wait_ready - sleep until BSY clears, or timeout
 196 *	@link: SFF link to wait ready status for
 197 *	@deadline: deadline jiffies for the operation
 198 *
 199 *	Sleep until ATA Status register bit BSY clears, or timeout
 200 *	occurs.
 201 *
 202 *	LOCKING:
 203 *	Kernel thread context (may sleep).
 204 *
 205 *	RETURNS:
 206 *	0 on success, -errno otherwise.
 207 */
 208int ata_sff_wait_ready(struct ata_link *link, unsigned long deadline)
 209{
 210	return ata_wait_ready(link, deadline, ata_sff_check_ready);
 211}
 212EXPORT_SYMBOL_GPL(ata_sff_wait_ready);
 213
 214/**
 215 *	ata_sff_set_devctl - Write device control reg
 216 *	@ap: port where the device is
 217 *	@ctl: value to write
 218 *
 219 *	Writes ATA device control register.
 220 *
 221 *	RETURN:
 222 *	true if the register exists, false if not.
 223 *
 224 *	LOCKING:
 225 *	Inherited from caller.
 226 */
 227static bool ata_sff_set_devctl(struct ata_port *ap, u8 ctl)
 228{
 229	if (ap->ops->sff_set_devctl) {
 230		ap->ops->sff_set_devctl(ap, ctl);
 231		return true;
 232	}
 233	if (ap->ioaddr.ctl_addr) {
 234		iowrite8(ctl, ap->ioaddr.ctl_addr);
 235		return true;
 236	}
 237
 238	return false;
 239}
 240
 241/**
 242 *	ata_sff_dev_select - Select device 0/1 on ATA bus
 243 *	@ap: ATA channel to manipulate
 244 *	@device: ATA device (numbered from zero) to select
 245 *
 246 *	Use the method defined in the ATA specification to
 247 *	make either device 0, or device 1, active on the
 248 *	ATA channel.  Works with both PIO and MMIO.
 249 *
 250 *	May be used as the dev_select() entry in ata_port_operations.
 251 *
 252 *	LOCKING:
 253 *	caller.
 254 */
 255void ata_sff_dev_select(struct ata_port *ap, unsigned int device)
 256{
 257	u8 tmp;
 258
 259	if (device == 0)
 260		tmp = ATA_DEVICE_OBS;
 261	else
 262		tmp = ATA_DEVICE_OBS | ATA_DEV1;
 263
 264	iowrite8(tmp, ap->ioaddr.device_addr);
 265	ata_sff_pause(ap);	/* needed; also flushes, for mmio */
 266}
 267EXPORT_SYMBOL_GPL(ata_sff_dev_select);
 268
 269/**
 270 *	ata_dev_select - Select device 0/1 on ATA bus
 271 *	@ap: ATA channel to manipulate
 272 *	@device: ATA device (numbered from zero) to select
 273 *	@wait: non-zero to wait for Status register BSY bit to clear
 274 *	@can_sleep: non-zero if context allows sleeping
 275 *
 276 *	Use the method defined in the ATA specification to
 277 *	make either device 0, or device 1, active on the
 278 *	ATA channel.
 279 *
 280 *	This is a high-level version of ata_sff_dev_select(), which
 281 *	additionally provides the services of inserting the proper
 282 *	pauses and status polling, where needed.
 283 *
 284 *	LOCKING:
 285 *	caller.
 286 */
 287static void ata_dev_select(struct ata_port *ap, unsigned int device,
 288			   unsigned int wait, unsigned int can_sleep)
 289{
 290	if (wait)
 291		ata_wait_idle(ap);
 292
 293	ap->ops->sff_dev_select(ap, device);
 294
 295	if (wait) {
 296		if (can_sleep && ap->link.device[device].class == ATA_DEV_ATAPI)
 297			ata_msleep(ap, 150);
 298		ata_wait_idle(ap);
 299	}
 300}
 301
 302/**
 303 *	ata_sff_irq_on - Enable interrupts on a port.
 304 *	@ap: Port on which interrupts are enabled.
 305 *
 306 *	Enable interrupts on a legacy IDE device using MMIO or PIO,
 307 *	wait for idle, clear any pending interrupts.
 308 *
 309 *	Note: may NOT be used as the sff_irq_on() entry in
 310 *	ata_port_operations.
 311 *
 312 *	LOCKING:
 313 *	Inherited from caller.
 314 */
 315void ata_sff_irq_on(struct ata_port *ap)
 316{
 317	if (ap->ops->sff_irq_on) {
 318		ap->ops->sff_irq_on(ap);
 319		return;
 320	}
 321
 322	ap->ctl &= ~ATA_NIEN;
 323	ap->last_ctl = ap->ctl;
 324
 325	ata_sff_set_devctl(ap, ap->ctl);
 326	ata_wait_idle(ap);
 327
 328	if (ap->ops->sff_irq_clear)
 329		ap->ops->sff_irq_clear(ap);
 330}
 331EXPORT_SYMBOL_GPL(ata_sff_irq_on);
 332
 333/**
 334 *	ata_sff_tf_load - send taskfile registers to host controller
 335 *	@ap: Port to which output is sent
 336 *	@tf: ATA taskfile register set
 337 *
 338 *	Outputs ATA taskfile to standard ATA host controller.
 339 *
 340 *	LOCKING:
 341 *	Inherited from caller.
 342 */
 343void ata_sff_tf_load(struct ata_port *ap, const struct ata_taskfile *tf)
 344{
 345	struct ata_ioports *ioaddr = &ap->ioaddr;
 346	unsigned int is_addr = tf->flags & ATA_TFLAG_ISADDR;
 347
 348	if (tf->ctl != ap->last_ctl) {
 349		if (ioaddr->ctl_addr)
 350			iowrite8(tf->ctl, ioaddr->ctl_addr);
 351		ap->last_ctl = tf->ctl;
 352		ata_wait_idle(ap);
 353	}
 354
 355	if (is_addr && (tf->flags & ATA_TFLAG_LBA48)) {
 356		WARN_ON_ONCE(!ioaddr->ctl_addr);
 357		iowrite8(tf->hob_feature, ioaddr->feature_addr);
 358		iowrite8(tf->hob_nsect, ioaddr->nsect_addr);
 359		iowrite8(tf->hob_lbal, ioaddr->lbal_addr);
 360		iowrite8(tf->hob_lbam, ioaddr->lbam_addr);
 361		iowrite8(tf->hob_lbah, ioaddr->lbah_addr);
 362	}
 363
 364	if (is_addr) {
 365		iowrite8(tf->feature, ioaddr->feature_addr);
 366		iowrite8(tf->nsect, ioaddr->nsect_addr);
 367		iowrite8(tf->lbal, ioaddr->lbal_addr);
 368		iowrite8(tf->lbam, ioaddr->lbam_addr);
 369		iowrite8(tf->lbah, ioaddr->lbah_addr);
 370	}
 371
 372	if (tf->flags & ATA_TFLAG_DEVICE)
 373		iowrite8(tf->device, ioaddr->device_addr);
 374
 375	ata_wait_idle(ap);
 376}
 377EXPORT_SYMBOL_GPL(ata_sff_tf_load);
 378
 379/**
 380 *	ata_sff_tf_read - input device's ATA taskfile shadow registers
 381 *	@ap: Port from which input is read
 382 *	@tf: ATA taskfile register set for storing input
 383 *
 384 *	Reads ATA taskfile registers for currently-selected device
 385 *	into @tf. Assumes the device has a fully SFF compliant task file
 386 *	layout and behaviour. If you device does not (eg has a different
 387 *	status method) then you will need to provide a replacement tf_read
 388 *
 389 *	LOCKING:
 390 *	Inherited from caller.
 391 */
 392void ata_sff_tf_read(struct ata_port *ap, struct ata_taskfile *tf)
 393{
 394	struct ata_ioports *ioaddr = &ap->ioaddr;
 395
 396	tf->status = ata_sff_check_status(ap);
 397	tf->error = ioread8(ioaddr->error_addr);
 398	tf->nsect = ioread8(ioaddr->nsect_addr);
 399	tf->lbal = ioread8(ioaddr->lbal_addr);
 400	tf->lbam = ioread8(ioaddr->lbam_addr);
 401	tf->lbah = ioread8(ioaddr->lbah_addr);
 402	tf->device = ioread8(ioaddr->device_addr);
 403
 404	if (tf->flags & ATA_TFLAG_LBA48) {
 405		if (likely(ioaddr->ctl_addr)) {
 406			iowrite8(tf->ctl | ATA_HOB, ioaddr->ctl_addr);
 407			tf->hob_feature = ioread8(ioaddr->error_addr);
 408			tf->hob_nsect = ioread8(ioaddr->nsect_addr);
 409			tf->hob_lbal = ioread8(ioaddr->lbal_addr);
 410			tf->hob_lbam = ioread8(ioaddr->lbam_addr);
 411			tf->hob_lbah = ioread8(ioaddr->lbah_addr);
 412			iowrite8(tf->ctl, ioaddr->ctl_addr);
 413			ap->last_ctl = tf->ctl;
 414		} else
 415			WARN_ON_ONCE(1);
 416	}
 417}
 418EXPORT_SYMBOL_GPL(ata_sff_tf_read);
 419
 420/**
 421 *	ata_sff_exec_command - issue ATA command to host controller
 422 *	@ap: port to which command is being issued
 423 *	@tf: ATA taskfile register set
 424 *
 425 *	Issues ATA command, with proper synchronization with interrupt
 426 *	handler / other threads.
 427 *
 428 *	LOCKING:
 429 *	spin_lock_irqsave(host lock)
 430 */
 431void ata_sff_exec_command(struct ata_port *ap, const struct ata_taskfile *tf)
 432{
 433	iowrite8(tf->command, ap->ioaddr.command_addr);
 434	ata_sff_pause(ap);
 435}
 436EXPORT_SYMBOL_GPL(ata_sff_exec_command);
 437
 438/**
 439 *	ata_tf_to_host - issue ATA taskfile to host controller
 440 *	@ap: port to which command is being issued
 441 *	@tf: ATA taskfile register set
 442 *	@tag: tag of the associated command
 443 *
 444 *	Issues ATA taskfile register set to ATA host controller,
 445 *	with proper synchronization with interrupt handler and
 446 *	other threads.
 447 *
 448 *	LOCKING:
 449 *	spin_lock_irqsave(host lock)
 450 */
 451static inline void ata_tf_to_host(struct ata_port *ap,
 452				  const struct ata_taskfile *tf,
 453				  unsigned int tag)
 454{
 455	trace_ata_tf_load(ap, tf);
 456	ap->ops->sff_tf_load(ap, tf);
 457	trace_ata_exec_command(ap, tf, tag);
 458	ap->ops->sff_exec_command(ap, tf);
 459}
 460
 461/**
 462 *	ata_sff_data_xfer - Transfer data by PIO
 463 *	@qc: queued command
 464 *	@buf: data buffer
 465 *	@buflen: buffer length
 466 *	@rw: read/write
 467 *
 468 *	Transfer data from/to the device data register by PIO.
 469 *
 470 *	LOCKING:
 471 *	Inherited from caller.
 472 *
 473 *	RETURNS:
 474 *	Bytes consumed.
 475 */
 476unsigned int ata_sff_data_xfer(struct ata_queued_cmd *qc, unsigned char *buf,
 477			       unsigned int buflen, int rw)
 478{
 479	struct ata_port *ap = qc->dev->link->ap;
 480	void __iomem *data_addr = ap->ioaddr.data_addr;
 481	unsigned int words = buflen >> 1;
 482
 483	/* Transfer multiple of 2 bytes */
 484	if (rw == READ)
 485		ioread16_rep(data_addr, buf, words);
 486	else
 487		iowrite16_rep(data_addr, buf, words);
 488
 489	/* Transfer trailing byte, if any. */
 490	if (unlikely(buflen & 0x01)) {
 491		unsigned char pad[2] = { };
 492
 493		/* Point buf to the tail of buffer */
 494		buf += buflen - 1;
 495
 496		/*
 497		 * Use io*16_rep() accessors here as well to avoid pointlessly
 498		 * swapping bytes to and from on the big endian machines...
 499		 */
 500		if (rw == READ) {
 501			ioread16_rep(data_addr, pad, 1);
 502			*buf = pad[0];
 503		} else {
 504			pad[0] = *buf;
 505			iowrite16_rep(data_addr, pad, 1);
 506		}
 507		words++;
 508	}
 509
 510	return words << 1;
 511}
 512EXPORT_SYMBOL_GPL(ata_sff_data_xfer);
 513
 514/**
 515 *	ata_sff_data_xfer32 - Transfer data by PIO
 516 *	@qc: queued command
 517 *	@buf: data buffer
 518 *	@buflen: buffer length
 519 *	@rw: read/write
 520 *
 521 *	Transfer data from/to the device data register by PIO using 32bit
 522 *	I/O operations.
 523 *
 524 *	LOCKING:
 525 *	Inherited from caller.
 526 *
 527 *	RETURNS:
 528 *	Bytes consumed.
 529 */
 530
 531unsigned int ata_sff_data_xfer32(struct ata_queued_cmd *qc, unsigned char *buf,
 532			       unsigned int buflen, int rw)
 533{
 534	struct ata_device *dev = qc->dev;
 535	struct ata_port *ap = dev->link->ap;
 536	void __iomem *data_addr = ap->ioaddr.data_addr;
 537	unsigned int words = buflen >> 2;
 538	int slop = buflen & 3;
 539
 540	if (!(ap->pflags & ATA_PFLAG_PIO32))
 541		return ata_sff_data_xfer(qc, buf, buflen, rw);
 542
 543	/* Transfer multiple of 4 bytes */
 544	if (rw == READ)
 545		ioread32_rep(data_addr, buf, words);
 546	else
 547		iowrite32_rep(data_addr, buf, words);
 548
 549	/* Transfer trailing bytes, if any */
 550	if (unlikely(slop)) {
 551		unsigned char pad[4] = { };
 552
 553		/* Point buf to the tail of buffer */
 554		buf += buflen - slop;
 555
 556		/*
 557		 * Use io*_rep() accessors here as well to avoid pointlessly
 558		 * swapping bytes to and from on the big endian machines...
 559		 */
 560		if (rw == READ) {
 561			if (slop < 3)
 562				ioread16_rep(data_addr, pad, 1);
 563			else
 564				ioread32_rep(data_addr, pad, 1);
 565			memcpy(buf, pad, slop);
 566		} else {
 567			memcpy(pad, buf, slop);
 568			if (slop < 3)
 569				iowrite16_rep(data_addr, pad, 1);
 570			else
 571				iowrite32_rep(data_addr, pad, 1);
 572		}
 573	}
 574	return (buflen + 1) & ~1;
 575}
 576EXPORT_SYMBOL_GPL(ata_sff_data_xfer32);
 577
 578static void ata_pio_xfer(struct ata_queued_cmd *qc, struct page *page,
 579		unsigned int offset, size_t xfer_size)
 580{
 581	bool do_write = (qc->tf.flags & ATA_TFLAG_WRITE);
 582	unsigned char *buf;
 583
 584	buf = kmap_atomic(page);
 585	qc->ap->ops->sff_data_xfer(qc, buf + offset, xfer_size, do_write);
 586	kunmap_atomic(buf);
 587
 588	if (!do_write && !PageSlab(page))
 589		flush_dcache_page(page);
 590}
 591
 592/**
 593 *	ata_pio_sector - Transfer a sector of data.
 594 *	@qc: Command on going
 595 *
 596 *	Transfer qc->sect_size bytes of data from/to the ATA device.
 597 *
 598 *	LOCKING:
 599 *	Inherited from caller.
 600 */
 601static void ata_pio_sector(struct ata_queued_cmd *qc)
 602{
 603	struct ata_port *ap = qc->ap;
 604	struct page *page;
 605	unsigned int offset;
 606
 607	if (!qc->cursg) {
 608		qc->curbytes = qc->nbytes;
 609		return;
 610	}
 611	if (qc->curbytes == qc->nbytes - qc->sect_size)
 612		ap->hsm_task_state = HSM_ST_LAST;
 613
 614	page = sg_page(qc->cursg);
 615	offset = qc->cursg->offset + qc->cursg_ofs;
 616
 617	/* get the current page and offset */
 618	page = nth_page(page, (offset >> PAGE_SHIFT));
 619	offset %= PAGE_SIZE;
 620
 621	trace_ata_sff_pio_transfer_data(qc, offset, qc->sect_size);
 
 
 
 622
 623	/*
 624	 * Split the transfer when it splits a page boundary.  Note that the
 625	 * split still has to be dword aligned like all ATA data transfers.
 626	 */
 627	WARN_ON_ONCE(offset % 4);
 628	if (offset + qc->sect_size > PAGE_SIZE) {
 629		unsigned int split_len = PAGE_SIZE - offset;
 630
 631		ata_pio_xfer(qc, page, offset, split_len);
 632		ata_pio_xfer(qc, nth_page(page, 1), 0,
 633			     qc->sect_size - split_len);
 634	} else {
 635		ata_pio_xfer(qc, page, offset, qc->sect_size);
 636	}
 637
 638	qc->curbytes += qc->sect_size;
 639	qc->cursg_ofs += qc->sect_size;
 640
 641	if (qc->cursg_ofs == qc->cursg->length) {
 642		qc->cursg = sg_next(qc->cursg);
 643		if (!qc->cursg)
 644			ap->hsm_task_state = HSM_ST_LAST;
 645		qc->cursg_ofs = 0;
 646	}
 647}
 648
 649/**
 650 *	ata_pio_sectors - Transfer one or many sectors.
 651 *	@qc: Command on going
 652 *
 653 *	Transfer one or many sectors of data from/to the
 654 *	ATA device for the DRQ request.
 655 *
 656 *	LOCKING:
 657 *	Inherited from caller.
 658 */
 659static void ata_pio_sectors(struct ata_queued_cmd *qc)
 660{
 661	if (is_multi_taskfile(&qc->tf)) {
 662		/* READ/WRITE MULTIPLE */
 663		unsigned int nsect;
 664
 665		WARN_ON_ONCE(qc->dev->multi_count == 0);
 666
 667		nsect = min((qc->nbytes - qc->curbytes) / qc->sect_size,
 668			    qc->dev->multi_count);
 669		while (nsect--)
 670			ata_pio_sector(qc);
 671	} else
 672		ata_pio_sector(qc);
 673
 674	ata_sff_sync(qc->ap); /* flush */
 675}
 676
 677/**
 678 *	atapi_send_cdb - Write CDB bytes to hardware
 679 *	@ap: Port to which ATAPI device is attached.
 680 *	@qc: Taskfile currently active
 681 *
 682 *	When device has indicated its readiness to accept
 683 *	a CDB, this function is called.  Send the CDB.
 684 *
 685 *	LOCKING:
 686 *	caller.
 687 */
 688static void atapi_send_cdb(struct ata_port *ap, struct ata_queued_cmd *qc)
 689{
 690	/* send SCSI cdb */
 691	trace_atapi_send_cdb(qc, 0, qc->dev->cdb_len);
 692	WARN_ON_ONCE(qc->dev->cdb_len < 12);
 693
 694	ap->ops->sff_data_xfer(qc, qc->cdb, qc->dev->cdb_len, 1);
 695	ata_sff_sync(ap);
 696	/* FIXME: If the CDB is for DMA do we need to do the transition delay
 697	   or is bmdma_start guaranteed to do it ? */
 698	switch (qc->tf.protocol) {
 699	case ATAPI_PROT_PIO:
 700		ap->hsm_task_state = HSM_ST;
 701		break;
 702	case ATAPI_PROT_NODATA:
 703		ap->hsm_task_state = HSM_ST_LAST;
 704		break;
 705#ifdef CONFIG_ATA_BMDMA
 706	case ATAPI_PROT_DMA:
 707		ap->hsm_task_state = HSM_ST_LAST;
 708		/* initiate bmdma */
 709		trace_ata_bmdma_start(ap, &qc->tf, qc->tag);
 710		ap->ops->bmdma_start(qc);
 711		break;
 712#endif /* CONFIG_ATA_BMDMA */
 713	default:
 714		BUG();
 715	}
 716}
 717
 718/**
 719 *	__atapi_pio_bytes - Transfer data from/to the ATAPI device.
 720 *	@qc: Command on going
 721 *	@bytes: number of bytes
 722 *
 723 *	Transfer data from/to the ATAPI device.
 724 *
 725 *	LOCKING:
 726 *	Inherited from caller.
 727 *
 728 */
 729static int __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
 730{
 731	int rw = (qc->tf.flags & ATA_TFLAG_WRITE) ? WRITE : READ;
 732	struct ata_port *ap = qc->ap;
 733	struct ata_device *dev = qc->dev;
 734	struct ata_eh_info *ehi = &dev->link->eh_info;
 735	struct scatterlist *sg;
 736	struct page *page;
 737	unsigned char *buf;
 738	unsigned int offset, count, consumed;
 739
 740next_sg:
 741	sg = qc->cursg;
 742	if (unlikely(!sg)) {
 743		ata_ehi_push_desc(ehi, "unexpected or too much trailing data "
 744				  "buf=%u cur=%u bytes=%u",
 745				  qc->nbytes, qc->curbytes, bytes);
 746		return -1;
 747	}
 748
 749	page = sg_page(sg);
 750	offset = sg->offset + qc->cursg_ofs;
 751
 752	/* get the current page and offset */
 753	page = nth_page(page, (offset >> PAGE_SHIFT));
 754	offset %= PAGE_SIZE;
 755
 756	/* don't overrun current sg */
 757	count = min(sg->length - qc->cursg_ofs, bytes);
 758
 759	/* don't cross page boundaries */
 760	count = min(count, (unsigned int)PAGE_SIZE - offset);
 761
 762	trace_atapi_pio_transfer_data(qc, offset, count);
 763
 764	/* do the actual data transfer */
 765	buf = kmap_atomic(page);
 766	consumed = ap->ops->sff_data_xfer(qc, buf + offset, count, rw);
 767	kunmap_atomic(buf);
 768
 769	bytes -= min(bytes, consumed);
 770	qc->curbytes += count;
 771	qc->cursg_ofs += count;
 772
 773	if (qc->cursg_ofs == sg->length) {
 774		qc->cursg = sg_next(qc->cursg);
 775		qc->cursg_ofs = 0;
 776	}
 777
 778	/*
 779	 * There used to be a  WARN_ON_ONCE(qc->cursg && count != consumed);
 780	 * Unfortunately __atapi_pio_bytes doesn't know enough to do the WARN
 781	 * check correctly as it doesn't know if it is the last request being
 782	 * made. Somebody should implement a proper sanity check.
 783	 */
 784	if (bytes)
 785		goto next_sg;
 786	return 0;
 787}
 788
 789/**
 790 *	atapi_pio_bytes - Transfer data from/to the ATAPI device.
 791 *	@qc: Command on going
 792 *
 793 *	Transfer Transfer data from/to the ATAPI device.
 794 *
 795 *	LOCKING:
 796 *	Inherited from caller.
 797 */
 798static void atapi_pio_bytes(struct ata_queued_cmd *qc)
 799{
 800	struct ata_port *ap = qc->ap;
 801	struct ata_device *dev = qc->dev;
 802	struct ata_eh_info *ehi = &dev->link->eh_info;
 803	unsigned int ireason, bc_lo, bc_hi, bytes;
 804	int i_write, do_write = (qc->tf.flags & ATA_TFLAG_WRITE) ? 1 : 0;
 805
 806	/* Abuse qc->result_tf for temp storage of intermediate TF
 807	 * here to save some kernel stack usage.
 808	 * For normal completion, qc->result_tf is not relevant. For
 809	 * error, qc->result_tf is later overwritten by ata_qc_complete().
 810	 * So, the correctness of qc->result_tf is not affected.
 811	 */
 812	ap->ops->sff_tf_read(ap, &qc->result_tf);
 813	ireason = qc->result_tf.nsect;
 814	bc_lo = qc->result_tf.lbam;
 815	bc_hi = qc->result_tf.lbah;
 816	bytes = (bc_hi << 8) | bc_lo;
 817
 818	/* shall be cleared to zero, indicating xfer of data */
 819	if (unlikely(ireason & ATAPI_COD))
 820		goto atapi_check;
 821
 822	/* make sure transfer direction matches expected */
 823	i_write = ((ireason & ATAPI_IO) == 0) ? 1 : 0;
 824	if (unlikely(do_write != i_write))
 825		goto atapi_check;
 826
 827	if (unlikely(!bytes))
 828		goto atapi_check;
 829
 830	if (unlikely(__atapi_pio_bytes(qc, bytes)))
 831		goto err_out;
 832	ata_sff_sync(ap); /* flush */
 833
 834	return;
 835
 836 atapi_check:
 837	ata_ehi_push_desc(ehi, "ATAPI check failed (ireason=0x%x bytes=%u)",
 838			  ireason, bytes);
 839 err_out:
 840	qc->err_mask |= AC_ERR_HSM;
 841	ap->hsm_task_state = HSM_ST_ERR;
 842}
 843
 844/**
 845 *	ata_hsm_ok_in_wq - Check if the qc can be handled in the workqueue.
 846 *	@ap: the target ata_port
 847 *	@qc: qc on going
 848 *
 849 *	RETURNS:
 850 *	1 if ok in workqueue, 0 otherwise.
 851 */
 852static inline int ata_hsm_ok_in_wq(struct ata_port *ap,
 853						struct ata_queued_cmd *qc)
 854{
 855	if (qc->tf.flags & ATA_TFLAG_POLLING)
 856		return 1;
 857
 858	if (ap->hsm_task_state == HSM_ST_FIRST) {
 859		if (qc->tf.protocol == ATA_PROT_PIO &&
 860		   (qc->tf.flags & ATA_TFLAG_WRITE))
 861		    return 1;
 862
 863		if (ata_is_atapi(qc->tf.protocol) &&
 864		   !(qc->dev->flags & ATA_DFLAG_CDB_INTR))
 865			return 1;
 866	}
 867
 868	return 0;
 869}
 870
 871/**
 872 *	ata_hsm_qc_complete - finish a qc running on standard HSM
 873 *	@qc: Command to complete
 874 *	@in_wq: 1 if called from workqueue, 0 otherwise
 875 *
 876 *	Finish @qc which is running on standard HSM.
 877 *
 878 *	LOCKING:
 879 *	If @in_wq is zero, spin_lock_irqsave(host lock).
 880 *	Otherwise, none on entry and grabs host lock.
 881 */
 882static void ata_hsm_qc_complete(struct ata_queued_cmd *qc, int in_wq)
 883{
 884	struct ata_port *ap = qc->ap;
 885
 886	if (ap->ops->error_handler) {
 887		if (in_wq) {
 888			/* EH might have kicked in while host lock is
 889			 * released.
 890			 */
 891			qc = ata_qc_from_tag(ap, qc->tag);
 892			if (qc) {
 893				if (likely(!(qc->err_mask & AC_ERR_HSM))) {
 894					ata_sff_irq_on(ap);
 895					ata_qc_complete(qc);
 896				} else
 897					ata_port_freeze(ap);
 898			}
 899		} else {
 900			if (likely(!(qc->err_mask & AC_ERR_HSM)))
 901				ata_qc_complete(qc);
 902			else
 903				ata_port_freeze(ap);
 904		}
 905	} else {
 906		if (in_wq) {
 907			ata_sff_irq_on(ap);
 908			ata_qc_complete(qc);
 909		} else
 910			ata_qc_complete(qc);
 
 
 911	}
 912}
 913
 914/**
 915 *	ata_sff_hsm_move - move the HSM to the next state.
 916 *	@ap: the target ata_port
 917 *	@qc: qc on going
 918 *	@status: current device status
 919 *	@in_wq: 1 if called from workqueue, 0 otherwise
 920 *
 921 *	RETURNS:
 922 *	1 when poll next status needed, 0 otherwise.
 923 */
 924int ata_sff_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc,
 925		     u8 status, int in_wq)
 926{
 927	struct ata_link *link = qc->dev->link;
 928	struct ata_eh_info *ehi = &link->eh_info;
 929	int poll_next;
 930
 931	lockdep_assert_held(ap->lock);
 932
 933	WARN_ON_ONCE((qc->flags & ATA_QCFLAG_ACTIVE) == 0);
 934
 935	/* Make sure ata_sff_qc_issue() does not throw things
 936	 * like DMA polling into the workqueue. Notice that
 937	 * in_wq is not equivalent to (qc->tf.flags & ATA_TFLAG_POLLING).
 938	 */
 939	WARN_ON_ONCE(in_wq != ata_hsm_ok_in_wq(ap, qc));
 940
 941fsm_start:
 942	trace_ata_sff_hsm_state(qc, status);
 943
 944	switch (ap->hsm_task_state) {
 945	case HSM_ST_FIRST:
 946		/* Send first data block or PACKET CDB */
 947
 948		/* If polling, we will stay in the work queue after
 949		 * sending the data. Otherwise, interrupt handler
 950		 * takes over after sending the data.
 951		 */
 952		poll_next = (qc->tf.flags & ATA_TFLAG_POLLING);
 953
 954		/* check device status */
 955		if (unlikely((status & ATA_DRQ) == 0)) {
 956			/* handle BSY=0, DRQ=0 as error */
 957			if (likely(status & (ATA_ERR | ATA_DF)))
 958				/* device stops HSM for abort/error */
 959				qc->err_mask |= AC_ERR_DEV;
 960			else {
 961				/* HSM violation. Let EH handle this */
 962				ata_ehi_push_desc(ehi,
 963					"ST_FIRST: !(DRQ|ERR|DF)");
 964				qc->err_mask |= AC_ERR_HSM;
 965			}
 966
 967			ap->hsm_task_state = HSM_ST_ERR;
 968			goto fsm_start;
 969		}
 970
 971		/* Device should not ask for data transfer (DRQ=1)
 972		 * when it finds something wrong.
 973		 * We ignore DRQ here and stop the HSM by
 974		 * changing hsm_task_state to HSM_ST_ERR and
 975		 * let the EH abort the command or reset the device.
 976		 */
 977		if (unlikely(status & (ATA_ERR | ATA_DF))) {
 978			/* Some ATAPI tape drives forget to clear the ERR bit
 979			 * when doing the next command (mostly request sense).
 980			 * We ignore ERR here to workaround and proceed sending
 981			 * the CDB.
 982			 */
 983			if (!(qc->dev->horkage & ATA_HORKAGE_STUCK_ERR)) {
 984				ata_ehi_push_desc(ehi, "ST_FIRST: "
 985					"DRQ=1 with device error, "
 986					"dev_stat 0x%X", status);
 987				qc->err_mask |= AC_ERR_HSM;
 988				ap->hsm_task_state = HSM_ST_ERR;
 989				goto fsm_start;
 990			}
 991		}
 992
 993		if (qc->tf.protocol == ATA_PROT_PIO) {
 994			/* PIO data out protocol.
 995			 * send first data block.
 996			 */
 997
 998			/* ata_pio_sectors() might change the state
 999			 * to HSM_ST_LAST. so, the state is changed here
1000			 * before ata_pio_sectors().
1001			 */
1002			ap->hsm_task_state = HSM_ST;
1003			ata_pio_sectors(qc);
1004		} else
1005			/* send CDB */
1006			atapi_send_cdb(ap, qc);
1007
1008		/* if polling, ata_sff_pio_task() handles the rest.
1009		 * otherwise, interrupt handler takes over from here.
1010		 */
1011		break;
1012
1013	case HSM_ST:
1014		/* complete command or read/write the data register */
1015		if (qc->tf.protocol == ATAPI_PROT_PIO) {
1016			/* ATAPI PIO protocol */
1017			if ((status & ATA_DRQ) == 0) {
1018				/* No more data to transfer or device error.
1019				 * Device error will be tagged in HSM_ST_LAST.
1020				 */
1021				ap->hsm_task_state = HSM_ST_LAST;
1022				goto fsm_start;
1023			}
1024
1025			/* Device should not ask for data transfer (DRQ=1)
1026			 * when it finds something wrong.
1027			 * We ignore DRQ here and stop the HSM by
1028			 * changing hsm_task_state to HSM_ST_ERR and
1029			 * let the EH abort the command or reset the device.
1030			 */
1031			if (unlikely(status & (ATA_ERR | ATA_DF))) {
1032				ata_ehi_push_desc(ehi, "ST-ATAPI: "
1033					"DRQ=1 with device error, "
1034					"dev_stat 0x%X", status);
1035				qc->err_mask |= AC_ERR_HSM;
1036				ap->hsm_task_state = HSM_ST_ERR;
1037				goto fsm_start;
1038			}
1039
1040			atapi_pio_bytes(qc);
1041
1042			if (unlikely(ap->hsm_task_state == HSM_ST_ERR))
1043				/* bad ireason reported by device */
1044				goto fsm_start;
1045
1046		} else {
1047			/* ATA PIO protocol */
1048			if (unlikely((status & ATA_DRQ) == 0)) {
1049				/* handle BSY=0, DRQ=0 as error */
1050				if (likely(status & (ATA_ERR | ATA_DF))) {
1051					/* device stops HSM for abort/error */
1052					qc->err_mask |= AC_ERR_DEV;
1053
1054					/* If diagnostic failed and this is
1055					 * IDENTIFY, it's likely a phantom
1056					 * device.  Mark hint.
1057					 */
1058					if (qc->dev->horkage &
1059					    ATA_HORKAGE_DIAGNOSTIC)
1060						qc->err_mask |=
1061							AC_ERR_NODEV_HINT;
1062				} else {
1063					/* HSM violation. Let EH handle this.
1064					 * Phantom devices also trigger this
1065					 * condition.  Mark hint.
1066					 */
1067					ata_ehi_push_desc(ehi, "ST-ATA: "
1068						"DRQ=0 without device error, "
1069						"dev_stat 0x%X", status);
1070					qc->err_mask |= AC_ERR_HSM |
1071							AC_ERR_NODEV_HINT;
1072				}
1073
1074				ap->hsm_task_state = HSM_ST_ERR;
1075				goto fsm_start;
1076			}
1077
1078			/* For PIO reads, some devices may ask for
1079			 * data transfer (DRQ=1) alone with ERR=1.
1080			 * We respect DRQ here and transfer one
1081			 * block of junk data before changing the
1082			 * hsm_task_state to HSM_ST_ERR.
1083			 *
1084			 * For PIO writes, ERR=1 DRQ=1 doesn't make
1085			 * sense since the data block has been
1086			 * transferred to the device.
1087			 */
1088			if (unlikely(status & (ATA_ERR | ATA_DF))) {
1089				/* data might be corrputed */
1090				qc->err_mask |= AC_ERR_DEV;
1091
1092				if (!(qc->tf.flags & ATA_TFLAG_WRITE)) {
1093					ata_pio_sectors(qc);
1094					status = ata_wait_idle(ap);
1095				}
1096
1097				if (status & (ATA_BUSY | ATA_DRQ)) {
1098					ata_ehi_push_desc(ehi, "ST-ATA: "
1099						"BUSY|DRQ persists on ERR|DF, "
1100						"dev_stat 0x%X", status);
1101					qc->err_mask |= AC_ERR_HSM;
1102				}
1103
1104				/* There are oddball controllers with
1105				 * status register stuck at 0x7f and
1106				 * lbal/m/h at zero which makes it
1107				 * pass all other presence detection
1108				 * mechanisms we have.  Set NODEV_HINT
1109				 * for it.  Kernel bz#7241.
1110				 */
1111				if (status == 0x7f)
1112					qc->err_mask |= AC_ERR_NODEV_HINT;
1113
1114				/* ata_pio_sectors() might change the
1115				 * state to HSM_ST_LAST. so, the state
1116				 * is changed after ata_pio_sectors().
1117				 */
1118				ap->hsm_task_state = HSM_ST_ERR;
1119				goto fsm_start;
1120			}
1121
1122			ata_pio_sectors(qc);
1123
1124			if (ap->hsm_task_state == HSM_ST_LAST &&
1125			    (!(qc->tf.flags & ATA_TFLAG_WRITE))) {
1126				/* all data read */
1127				status = ata_wait_idle(ap);
1128				goto fsm_start;
1129			}
1130		}
1131
1132		poll_next = 1;
1133		break;
1134
1135	case HSM_ST_LAST:
1136		if (unlikely(!ata_ok(status))) {
1137			qc->err_mask |= __ac_err_mask(status);
1138			ap->hsm_task_state = HSM_ST_ERR;
1139			goto fsm_start;
1140		}
1141
1142		/* no more data to transfer */
1143		trace_ata_sff_hsm_command_complete(qc, status);
1144
1145		WARN_ON_ONCE(qc->err_mask & (AC_ERR_DEV | AC_ERR_HSM));
1146
1147		ap->hsm_task_state = HSM_ST_IDLE;
1148
1149		/* complete taskfile transaction */
1150		ata_hsm_qc_complete(qc, in_wq);
1151
1152		poll_next = 0;
1153		break;
1154
1155	case HSM_ST_ERR:
1156		ap->hsm_task_state = HSM_ST_IDLE;
1157
1158		/* complete taskfile transaction */
1159		ata_hsm_qc_complete(qc, in_wq);
1160
1161		poll_next = 0;
1162		break;
1163	default:
1164		poll_next = 0;
1165		WARN(true, "ata%d: SFF host state machine in invalid state %d",
1166		     ap->print_id, ap->hsm_task_state);
1167	}
1168
1169	return poll_next;
1170}
1171EXPORT_SYMBOL_GPL(ata_sff_hsm_move);
1172
1173void ata_sff_queue_work(struct work_struct *work)
1174{
1175	queue_work(ata_sff_wq, work);
1176}
1177EXPORT_SYMBOL_GPL(ata_sff_queue_work);
1178
1179void ata_sff_queue_delayed_work(struct delayed_work *dwork, unsigned long delay)
1180{
1181	queue_delayed_work(ata_sff_wq, dwork, delay);
1182}
1183EXPORT_SYMBOL_GPL(ata_sff_queue_delayed_work);
1184
1185void ata_sff_queue_pio_task(struct ata_link *link, unsigned long delay)
1186{
1187	struct ata_port *ap = link->ap;
1188
1189	WARN_ON((ap->sff_pio_task_link != NULL) &&
1190		(ap->sff_pio_task_link != link));
1191	ap->sff_pio_task_link = link;
1192
1193	/* may fail if ata_sff_flush_pio_task() in progress */
1194	ata_sff_queue_delayed_work(&ap->sff_pio_task, msecs_to_jiffies(delay));
1195}
1196EXPORT_SYMBOL_GPL(ata_sff_queue_pio_task);
1197
1198void ata_sff_flush_pio_task(struct ata_port *ap)
1199{
1200	trace_ata_sff_flush_pio_task(ap);
1201
1202	cancel_delayed_work_sync(&ap->sff_pio_task);
1203
1204	/*
1205	 * We wanna reset the HSM state to IDLE.  If we do so without
1206	 * grabbing the port lock, critical sections protected by it which
1207	 * expect the HSM state to stay stable may get surprised.  For
1208	 * example, we may set IDLE in between the time
1209	 * __ata_sff_port_intr() checks for HSM_ST_IDLE and before it calls
1210	 * ata_sff_hsm_move() causing ata_sff_hsm_move() to BUG().
1211	 */
1212	spin_lock_irq(ap->lock);
1213	ap->hsm_task_state = HSM_ST_IDLE;
1214	spin_unlock_irq(ap->lock);
1215
1216	ap->sff_pio_task_link = NULL;
1217}
1218
1219static void ata_sff_pio_task(struct work_struct *work)
1220{
1221	struct ata_port *ap =
1222		container_of(work, struct ata_port, sff_pio_task.work);
1223	struct ata_link *link = ap->sff_pio_task_link;
1224	struct ata_queued_cmd *qc;
1225	u8 status;
1226	int poll_next;
1227
1228	spin_lock_irq(ap->lock);
1229
1230	BUG_ON(ap->sff_pio_task_link == NULL);
1231	/* qc can be NULL if timeout occurred */
1232	qc = ata_qc_from_tag(ap, link->active_tag);
1233	if (!qc) {
1234		ap->sff_pio_task_link = NULL;
1235		goto out_unlock;
1236	}
1237
1238fsm_start:
1239	WARN_ON_ONCE(ap->hsm_task_state == HSM_ST_IDLE);
1240
1241	/*
1242	 * This is purely heuristic.  This is a fast path.
1243	 * Sometimes when we enter, BSY will be cleared in
1244	 * a chk-status or two.  If not, the drive is probably seeking
1245	 * or something.  Snooze for a couple msecs, then
1246	 * chk-status again.  If still busy, queue delayed work.
1247	 */
1248	status = ata_sff_busy_wait(ap, ATA_BUSY, 5);
1249	if (status & ATA_BUSY) {
1250		spin_unlock_irq(ap->lock);
1251		ata_msleep(ap, 2);
1252		spin_lock_irq(ap->lock);
1253
1254		status = ata_sff_busy_wait(ap, ATA_BUSY, 10);
1255		if (status & ATA_BUSY) {
1256			ata_sff_queue_pio_task(link, ATA_SHORT_PAUSE);
1257			goto out_unlock;
1258		}
1259	}
1260
1261	/*
1262	 * hsm_move() may trigger another command to be processed.
1263	 * clean the link beforehand.
1264	 */
1265	ap->sff_pio_task_link = NULL;
1266	/* move the HSM */
1267	poll_next = ata_sff_hsm_move(ap, qc, status, 1);
1268
1269	/* another command or interrupt handler
1270	 * may be running at this point.
1271	 */
1272	if (poll_next)
1273		goto fsm_start;
1274out_unlock:
1275	spin_unlock_irq(ap->lock);
1276}
1277
1278/**
1279 *	ata_sff_qc_issue - issue taskfile to a SFF controller
1280 *	@qc: command to issue to device
1281 *
1282 *	This function issues a PIO or NODATA command to a SFF
1283 *	controller.
1284 *
1285 *	LOCKING:
1286 *	spin_lock_irqsave(host lock)
1287 *
1288 *	RETURNS:
1289 *	Zero on success, AC_ERR_* mask on failure
1290 */
1291unsigned int ata_sff_qc_issue(struct ata_queued_cmd *qc)
1292{
1293	struct ata_port *ap = qc->ap;
1294	struct ata_link *link = qc->dev->link;
1295
1296	/* Use polling pio if the LLD doesn't handle
1297	 * interrupt driven pio and atapi CDB interrupt.
1298	 */
1299	if (ap->flags & ATA_FLAG_PIO_POLLING)
1300		qc->tf.flags |= ATA_TFLAG_POLLING;
1301
1302	/* select the device */
1303	ata_dev_select(ap, qc->dev->devno, 1, 0);
1304
1305	/* start the command */
1306	switch (qc->tf.protocol) {
1307	case ATA_PROT_NODATA:
1308		if (qc->tf.flags & ATA_TFLAG_POLLING)
1309			ata_qc_set_polling(qc);
1310
1311		ata_tf_to_host(ap, &qc->tf, qc->tag);
1312		ap->hsm_task_state = HSM_ST_LAST;
1313
1314		if (qc->tf.flags & ATA_TFLAG_POLLING)
1315			ata_sff_queue_pio_task(link, 0);
1316
1317		break;
1318
1319	case ATA_PROT_PIO:
1320		if (qc->tf.flags & ATA_TFLAG_POLLING)
1321			ata_qc_set_polling(qc);
1322
1323		ata_tf_to_host(ap, &qc->tf, qc->tag);
1324
1325		if (qc->tf.flags & ATA_TFLAG_WRITE) {
1326			/* PIO data out protocol */
1327			ap->hsm_task_state = HSM_ST_FIRST;
1328			ata_sff_queue_pio_task(link, 0);
1329
1330			/* always send first data block using the
1331			 * ata_sff_pio_task() codepath.
1332			 */
1333		} else {
1334			/* PIO data in protocol */
1335			ap->hsm_task_state = HSM_ST;
1336
1337			if (qc->tf.flags & ATA_TFLAG_POLLING)
1338				ata_sff_queue_pio_task(link, 0);
1339
1340			/* if polling, ata_sff_pio_task() handles the
1341			 * rest.  otherwise, interrupt handler takes
1342			 * over from here.
1343			 */
1344		}
1345
1346		break;
1347
1348	case ATAPI_PROT_PIO:
1349	case ATAPI_PROT_NODATA:
1350		if (qc->tf.flags & ATA_TFLAG_POLLING)
1351			ata_qc_set_polling(qc);
1352
1353		ata_tf_to_host(ap, &qc->tf, qc->tag);
1354
1355		ap->hsm_task_state = HSM_ST_FIRST;
1356
1357		/* send cdb by polling if no cdb interrupt */
1358		if ((!(qc->dev->flags & ATA_DFLAG_CDB_INTR)) ||
1359		    (qc->tf.flags & ATA_TFLAG_POLLING))
1360			ata_sff_queue_pio_task(link, 0);
1361		break;
1362
1363	default:
1364		return AC_ERR_SYSTEM;
1365	}
1366
1367	return 0;
1368}
1369EXPORT_SYMBOL_GPL(ata_sff_qc_issue);
1370
1371/**
1372 *	ata_sff_qc_fill_rtf - fill result TF using ->sff_tf_read
1373 *	@qc: qc to fill result TF for
1374 *
1375 *	@qc is finished and result TF needs to be filled.  Fill it
1376 *	using ->sff_tf_read.
1377 *
1378 *	LOCKING:
1379 *	spin_lock_irqsave(host lock)
1380 *
1381 *	RETURNS:
1382 *	true indicating that result TF is successfully filled.
1383 */
1384bool ata_sff_qc_fill_rtf(struct ata_queued_cmd *qc)
1385{
1386	qc->ap->ops->sff_tf_read(qc->ap, &qc->result_tf);
1387	return true;
1388}
1389EXPORT_SYMBOL_GPL(ata_sff_qc_fill_rtf);
1390
1391static unsigned int ata_sff_idle_irq(struct ata_port *ap)
1392{
1393	ap->stats.idle_irq++;
1394
1395#ifdef ATA_IRQ_TRAP
1396	if ((ap->stats.idle_irq % 1000) == 0) {
1397		ap->ops->sff_check_status(ap);
1398		if (ap->ops->sff_irq_clear)
1399			ap->ops->sff_irq_clear(ap);
1400		ata_port_warn(ap, "irq trap\n");
1401		return 1;
1402	}
1403#endif
1404	return 0;	/* irq not handled */
1405}
1406
1407static unsigned int __ata_sff_port_intr(struct ata_port *ap,
1408					struct ata_queued_cmd *qc,
1409					bool hsmv_on_idle)
1410{
1411	u8 status;
1412
1413	trace_ata_sff_port_intr(qc, hsmv_on_idle);
1414
1415	/* Check whether we are expecting interrupt in this state */
1416	switch (ap->hsm_task_state) {
1417	case HSM_ST_FIRST:
1418		/* Some pre-ATAPI-4 devices assert INTRQ
1419		 * at this state when ready to receive CDB.
1420		 */
1421
1422		/* Check the ATA_DFLAG_CDB_INTR flag is enough here.
1423		 * The flag was turned on only for atapi devices.  No
1424		 * need to check ata_is_atapi(qc->tf.protocol) again.
1425		 */
1426		if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
1427			return ata_sff_idle_irq(ap);
1428		break;
1429	case HSM_ST_IDLE:
1430		return ata_sff_idle_irq(ap);
1431	default:
1432		break;
1433	}
1434
1435	/* check main status, clearing INTRQ if needed */
1436	status = ata_sff_irq_status(ap);
1437	if (status & ATA_BUSY) {
1438		if (hsmv_on_idle) {
1439			/* BMDMA engine is already stopped, we're screwed */
1440			qc->err_mask |= AC_ERR_HSM;
1441			ap->hsm_task_state = HSM_ST_ERR;
1442		} else
1443			return ata_sff_idle_irq(ap);
1444	}
1445
1446	/* clear irq events */
1447	if (ap->ops->sff_irq_clear)
1448		ap->ops->sff_irq_clear(ap);
1449
1450	ata_sff_hsm_move(ap, qc, status, 0);
1451
1452	return 1;	/* irq handled */
1453}
1454
1455/**
1456 *	ata_sff_port_intr - Handle SFF port interrupt
1457 *	@ap: Port on which interrupt arrived (possibly...)
1458 *	@qc: Taskfile currently active in engine
1459 *
1460 *	Handle port interrupt for given queued command.
1461 *
1462 *	LOCKING:
1463 *	spin_lock_irqsave(host lock)
1464 *
1465 *	RETURNS:
1466 *	One if interrupt was handled, zero if not (shared irq).
1467 */
1468unsigned int ata_sff_port_intr(struct ata_port *ap, struct ata_queued_cmd *qc)
1469{
1470	return __ata_sff_port_intr(ap, qc, false);
1471}
1472EXPORT_SYMBOL_GPL(ata_sff_port_intr);
1473
1474static inline irqreturn_t __ata_sff_interrupt(int irq, void *dev_instance,
1475	unsigned int (*port_intr)(struct ata_port *, struct ata_queued_cmd *))
1476{
1477	struct ata_host *host = dev_instance;
1478	bool retried = false;
1479	unsigned int i;
1480	unsigned int handled, idle, polling;
1481	unsigned long flags;
1482
1483	/* TODO: make _irqsave conditional on x86 PCI IDE legacy mode */
1484	spin_lock_irqsave(&host->lock, flags);
1485
1486retry:
1487	handled = idle = polling = 0;
1488	for (i = 0; i < host->n_ports; i++) {
1489		struct ata_port *ap = host->ports[i];
1490		struct ata_queued_cmd *qc;
1491
1492		qc = ata_qc_from_tag(ap, ap->link.active_tag);
1493		if (qc) {
1494			if (!(qc->tf.flags & ATA_TFLAG_POLLING))
1495				handled |= port_intr(ap, qc);
1496			else
1497				polling |= 1 << i;
1498		} else
1499			idle |= 1 << i;
1500	}
1501
1502	/*
1503	 * If no port was expecting IRQ but the controller is actually
1504	 * asserting IRQ line, nobody cared will ensue.  Check IRQ
1505	 * pending status if available and clear spurious IRQ.
1506	 */
1507	if (!handled && !retried) {
1508		bool retry = false;
1509
1510		for (i = 0; i < host->n_ports; i++) {
1511			struct ata_port *ap = host->ports[i];
1512
1513			if (polling & (1 << i))
1514				continue;
1515
1516			if (!ap->ops->sff_irq_check ||
1517			    !ap->ops->sff_irq_check(ap))
1518				continue;
1519
1520			if (idle & (1 << i)) {
1521				ap->ops->sff_check_status(ap);
1522				if (ap->ops->sff_irq_clear)
1523					ap->ops->sff_irq_clear(ap);
1524			} else {
1525				/* clear INTRQ and check if BUSY cleared */
1526				if (!(ap->ops->sff_check_status(ap) & ATA_BUSY))
1527					retry |= true;
1528				/*
1529				 * With command in flight, we can't do
1530				 * sff_irq_clear() w/o racing with completion.
1531				 */
1532			}
1533		}
1534
1535		if (retry) {
1536			retried = true;
1537			goto retry;
1538		}
1539	}
1540
1541	spin_unlock_irqrestore(&host->lock, flags);
1542
1543	return IRQ_RETVAL(handled);
1544}
1545
1546/**
1547 *	ata_sff_interrupt - Default SFF ATA host interrupt handler
1548 *	@irq: irq line (unused)
1549 *	@dev_instance: pointer to our ata_host information structure
1550 *
1551 *	Default interrupt handler for PCI IDE devices.  Calls
1552 *	ata_sff_port_intr() for each port that is not disabled.
1553 *
1554 *	LOCKING:
1555 *	Obtains host lock during operation.
1556 *
1557 *	RETURNS:
1558 *	IRQ_NONE or IRQ_HANDLED.
1559 */
1560irqreturn_t ata_sff_interrupt(int irq, void *dev_instance)
1561{
1562	return __ata_sff_interrupt(irq, dev_instance, ata_sff_port_intr);
1563}
1564EXPORT_SYMBOL_GPL(ata_sff_interrupt);
1565
1566/**
1567 *	ata_sff_lost_interrupt	-	Check for an apparent lost interrupt
1568 *	@ap: port that appears to have timed out
1569 *
1570 *	Called from the libata error handlers when the core code suspects
1571 *	an interrupt has been lost. If it has complete anything we can and
1572 *	then return. Interface must support altstatus for this faster
1573 *	recovery to occur.
1574 *
1575 *	Locking:
1576 *	Caller holds host lock
1577 */
1578
1579void ata_sff_lost_interrupt(struct ata_port *ap)
1580{
1581	u8 status = 0;
1582	struct ata_queued_cmd *qc;
1583
1584	/* Only one outstanding command per SFF channel */
1585	qc = ata_qc_from_tag(ap, ap->link.active_tag);
1586	/* We cannot lose an interrupt on a non-existent or polled command */
1587	if (!qc || qc->tf.flags & ATA_TFLAG_POLLING)
1588		return;
1589	/* See if the controller thinks it is still busy - if so the command
1590	   isn't a lost IRQ but is still in progress */
1591	if (WARN_ON_ONCE(!ata_sff_altstatus(ap, &status)))
1592		return;
1593	if (status & ATA_BUSY)
1594		return;
1595
1596	/* There was a command running, we are no longer busy and we have
1597	   no interrupt. */
1598	ata_port_warn(ap, "lost interrupt (Status 0x%x)\n", status);
1599	/* Run the host interrupt logic as if the interrupt had not been
1600	   lost */
1601	ata_sff_port_intr(ap, qc);
1602}
1603EXPORT_SYMBOL_GPL(ata_sff_lost_interrupt);
1604
1605/**
1606 *	ata_sff_freeze - Freeze SFF controller port
1607 *	@ap: port to freeze
1608 *
1609 *	Freeze SFF controller port.
1610 *
1611 *	LOCKING:
1612 *	Inherited from caller.
1613 */
1614void ata_sff_freeze(struct ata_port *ap)
1615{
1616	ap->ctl |= ATA_NIEN;
1617	ap->last_ctl = ap->ctl;
1618
1619	ata_sff_set_devctl(ap, ap->ctl);
1620
1621	/* Under certain circumstances, some controllers raise IRQ on
1622	 * ATA_NIEN manipulation.  Also, many controllers fail to mask
1623	 * previously pending IRQ on ATA_NIEN assertion.  Clear it.
1624	 */
1625	ap->ops->sff_check_status(ap);
1626
1627	if (ap->ops->sff_irq_clear)
1628		ap->ops->sff_irq_clear(ap);
1629}
1630EXPORT_SYMBOL_GPL(ata_sff_freeze);
1631
1632/**
1633 *	ata_sff_thaw - Thaw SFF controller port
1634 *	@ap: port to thaw
1635 *
1636 *	Thaw SFF controller port.
1637 *
1638 *	LOCKING:
1639 *	Inherited from caller.
1640 */
1641void ata_sff_thaw(struct ata_port *ap)
1642{
1643	/* clear & re-enable interrupts */
1644	ap->ops->sff_check_status(ap);
1645	if (ap->ops->sff_irq_clear)
1646		ap->ops->sff_irq_clear(ap);
1647	ata_sff_irq_on(ap);
1648}
1649EXPORT_SYMBOL_GPL(ata_sff_thaw);
1650
1651/**
1652 *	ata_sff_prereset - prepare SFF link for reset
1653 *	@link: SFF link to be reset
1654 *	@deadline: deadline jiffies for the operation
1655 *
1656 *	SFF link @link is about to be reset.  Initialize it.  It first
1657 *	calls ata_std_prereset() and wait for !BSY if the port is
1658 *	being softreset.
1659 *
1660 *	LOCKING:
1661 *	Kernel thread context (may sleep)
1662 *
1663 *	RETURNS:
1664 *	Always 0.
1665 */
1666int ata_sff_prereset(struct ata_link *link, unsigned long deadline)
1667{
1668	struct ata_eh_context *ehc = &link->eh_context;
1669	int rc;
1670
1671	/* The standard prereset is best-effort and always returns 0 */
1672	ata_std_prereset(link, deadline);
1673
1674	/* if we're about to do hardreset, nothing more to do */
1675	if (ehc->i.action & ATA_EH_HARDRESET)
1676		return 0;
1677
1678	/* wait for !BSY if we don't know that no device is attached */
1679	if (!ata_link_offline(link)) {
1680		rc = ata_sff_wait_ready(link, deadline);
1681		if (rc && rc != -ENODEV) {
1682			ata_link_warn(link,
1683				      "device not ready (errno=%d), forcing hardreset\n",
1684				      rc);
1685			ehc->i.action |= ATA_EH_HARDRESET;
1686		}
1687	}
1688
1689	return 0;
1690}
1691EXPORT_SYMBOL_GPL(ata_sff_prereset);
1692
1693/**
1694 *	ata_devchk - PATA device presence detection
1695 *	@ap: ATA channel to examine
1696 *	@device: Device to examine (starting at zero)
1697 *
1698 *	This technique was originally described in
1699 *	Hale Landis's ATADRVR (www.ata-atapi.com), and
1700 *	later found its way into the ATA/ATAPI spec.
1701 *
1702 *	Write a pattern to the ATA shadow registers,
1703 *	and if a device is present, it will respond by
1704 *	correctly storing and echoing back the
1705 *	ATA shadow register contents.
1706 *
1707 *	RETURN:
1708 *	true if device is present, false if not.
1709 *
1710 *	LOCKING:
1711 *	caller.
1712 */
1713static bool ata_devchk(struct ata_port *ap, unsigned int device)
1714{
1715	struct ata_ioports *ioaddr = &ap->ioaddr;
1716	u8 nsect, lbal;
1717
1718	ap->ops->sff_dev_select(ap, device);
1719
1720	iowrite8(0x55, ioaddr->nsect_addr);
1721	iowrite8(0xaa, ioaddr->lbal_addr);
1722
1723	iowrite8(0xaa, ioaddr->nsect_addr);
1724	iowrite8(0x55, ioaddr->lbal_addr);
1725
1726	iowrite8(0x55, ioaddr->nsect_addr);
1727	iowrite8(0xaa, ioaddr->lbal_addr);
1728
1729	nsect = ioread8(ioaddr->nsect_addr);
1730	lbal = ioread8(ioaddr->lbal_addr);
1731
1732	if ((nsect == 0x55) && (lbal == 0xaa))
1733		return true;	/* we found a device */
1734
1735	return false;		/* nothing found */
1736}
1737
1738/**
1739 *	ata_sff_dev_classify - Parse returned ATA device signature
1740 *	@dev: ATA device to classify (starting at zero)
1741 *	@present: device seems present
1742 *	@r_err: Value of error register on completion
1743 *
1744 *	After an event -- SRST, E.D.D., or SATA COMRESET -- occurs,
1745 *	an ATA/ATAPI-defined set of values is placed in the ATA
1746 *	shadow registers, indicating the results of device detection
1747 *	and diagnostics.
1748 *
1749 *	Select the ATA device, and read the values from the ATA shadow
1750 *	registers.  Then parse according to the Error register value,
1751 *	and the spec-defined values examined by ata_dev_classify().
1752 *
1753 *	LOCKING:
1754 *	caller.
1755 *
1756 *	RETURNS:
1757 *	Device type - %ATA_DEV_ATA, %ATA_DEV_ATAPI or %ATA_DEV_NONE.
1758 */
1759unsigned int ata_sff_dev_classify(struct ata_device *dev, int present,
1760				  u8 *r_err)
1761{
1762	struct ata_port *ap = dev->link->ap;
1763	struct ata_taskfile tf;
1764	unsigned int class;
1765	u8 err;
1766
1767	ap->ops->sff_dev_select(ap, dev->devno);
1768
1769	memset(&tf, 0, sizeof(tf));
1770
1771	ap->ops->sff_tf_read(ap, &tf);
1772	err = tf.error;
1773	if (r_err)
1774		*r_err = err;
1775
1776	/* see if device passed diags: continue and warn later */
1777	if (err == 0)
1778		/* diagnostic fail : do nothing _YET_ */
1779		dev->horkage |= ATA_HORKAGE_DIAGNOSTIC;
1780	else if (err == 1)
1781		/* do nothing */ ;
1782	else if ((dev->devno == 0) && (err == 0x81))
1783		/* do nothing */ ;
1784	else
1785		return ATA_DEV_NONE;
1786
1787	/* determine if device is ATA or ATAPI */
1788	class = ata_port_classify(ap, &tf);
1789	switch (class) {
1790	case ATA_DEV_UNKNOWN:
1791		/*
1792		 * If the device failed diagnostic, it's likely to
1793		 * have reported incorrect device signature too.
1794		 * Assume ATA device if the device seems present but
1795		 * device signature is invalid with diagnostic
1796		 * failure.
1797		 */
1798		if (present && (dev->horkage & ATA_HORKAGE_DIAGNOSTIC))
1799			class = ATA_DEV_ATA;
1800		else
1801			class = ATA_DEV_NONE;
1802		break;
1803	case ATA_DEV_ATA:
1804		if (ap->ops->sff_check_status(ap) == 0)
1805			class = ATA_DEV_NONE;
1806		break;
1807	}
1808	return class;
1809}
1810EXPORT_SYMBOL_GPL(ata_sff_dev_classify);
1811
1812/**
1813 *	ata_sff_wait_after_reset - wait for devices to become ready after reset
1814 *	@link: SFF link which is just reset
1815 *	@devmask: mask of present devices
1816 *	@deadline: deadline jiffies for the operation
1817 *
1818 *	Wait devices attached to SFF @link to become ready after
1819 *	reset.  It contains preceding 150ms wait to avoid accessing TF
1820 *	status register too early.
1821 *
1822 *	LOCKING:
1823 *	Kernel thread context (may sleep).
1824 *
1825 *	RETURNS:
1826 *	0 on success, -ENODEV if some or all of devices in @devmask
1827 *	don't seem to exist.  -errno on other errors.
1828 */
1829int ata_sff_wait_after_reset(struct ata_link *link, unsigned int devmask,
1830			     unsigned long deadline)
1831{
1832	struct ata_port *ap = link->ap;
1833	struct ata_ioports *ioaddr = &ap->ioaddr;
1834	unsigned int dev0 = devmask & (1 << 0);
1835	unsigned int dev1 = devmask & (1 << 1);
1836	int rc, ret = 0;
1837
1838	ata_msleep(ap, ATA_WAIT_AFTER_RESET);
1839
1840	/* always check readiness of the master device */
1841	rc = ata_sff_wait_ready(link, deadline);
1842	/* -ENODEV means the odd clown forgot the D7 pulldown resistor
1843	 * and TF status is 0xff, bail out on it too.
1844	 */
1845	if (rc)
1846		return rc;
1847
1848	/* if device 1 was found in ata_devchk, wait for register
1849	 * access briefly, then wait for BSY to clear.
1850	 */
1851	if (dev1) {
1852		int i;
1853
1854		ap->ops->sff_dev_select(ap, 1);
1855
1856		/* Wait for register access.  Some ATAPI devices fail
1857		 * to set nsect/lbal after reset, so don't waste too
1858		 * much time on it.  We're gonna wait for !BSY anyway.
1859		 */
1860		for (i = 0; i < 2; i++) {
1861			u8 nsect, lbal;
1862
1863			nsect = ioread8(ioaddr->nsect_addr);
1864			lbal = ioread8(ioaddr->lbal_addr);
1865			if ((nsect == 1) && (lbal == 1))
1866				break;
1867			ata_msleep(ap, 50);	/* give drive a breather */
1868		}
1869
1870		rc = ata_sff_wait_ready(link, deadline);
1871		if (rc) {
1872			if (rc != -ENODEV)
1873				return rc;
1874			ret = rc;
1875		}
1876	}
1877
1878	/* is all this really necessary? */
1879	ap->ops->sff_dev_select(ap, 0);
1880	if (dev1)
1881		ap->ops->sff_dev_select(ap, 1);
1882	if (dev0)
1883		ap->ops->sff_dev_select(ap, 0);
1884
1885	return ret;
1886}
1887EXPORT_SYMBOL_GPL(ata_sff_wait_after_reset);
1888
1889static int ata_bus_softreset(struct ata_port *ap, unsigned int devmask,
1890			     unsigned long deadline)
1891{
1892	struct ata_ioports *ioaddr = &ap->ioaddr;
1893
1894	if (ap->ioaddr.ctl_addr) {
1895		/* software reset.  causes dev0 to be selected */
1896		iowrite8(ap->ctl, ioaddr->ctl_addr);
1897		udelay(20);	/* FIXME: flush */
1898		iowrite8(ap->ctl | ATA_SRST, ioaddr->ctl_addr);
1899		udelay(20);	/* FIXME: flush */
1900		iowrite8(ap->ctl, ioaddr->ctl_addr);
1901		ap->last_ctl = ap->ctl;
1902	}
1903
1904	/* wait the port to become ready */
1905	return ata_sff_wait_after_reset(&ap->link, devmask, deadline);
1906}
1907
1908/**
1909 *	ata_sff_softreset - reset host port via ATA SRST
1910 *	@link: ATA link to reset
1911 *	@classes: resulting classes of attached devices
1912 *	@deadline: deadline jiffies for the operation
1913 *
1914 *	Reset host port using ATA SRST.
1915 *
1916 *	LOCKING:
1917 *	Kernel thread context (may sleep)
1918 *
1919 *	RETURNS:
1920 *	0 on success, -errno otherwise.
1921 */
1922int ata_sff_softreset(struct ata_link *link, unsigned int *classes,
1923		      unsigned long deadline)
1924{
1925	struct ata_port *ap = link->ap;
1926	unsigned int slave_possible = ap->flags & ATA_FLAG_SLAVE_POSS;
1927	unsigned int devmask = 0;
1928	int rc;
1929	u8 err;
1930
1931	/* determine if device 0/1 are present */
1932	if (ata_devchk(ap, 0))
1933		devmask |= (1 << 0);
1934	if (slave_possible && ata_devchk(ap, 1))
1935		devmask |= (1 << 1);
1936
1937	/* select device 0 again */
1938	ap->ops->sff_dev_select(ap, 0);
1939
1940	/* issue bus reset */
1941	rc = ata_bus_softreset(ap, devmask, deadline);
1942	/* if link is occupied, -ENODEV too is an error */
1943	if (rc && (rc != -ENODEV || sata_scr_valid(link))) {
1944		ata_link_err(link, "SRST failed (errno=%d)\n", rc);
1945		return rc;
1946	}
1947
1948	/* determine by signature whether we have ATA or ATAPI devices */
1949	classes[0] = ata_sff_dev_classify(&link->device[0],
1950					  devmask & (1 << 0), &err);
1951	if (slave_possible && err != 0x81)
1952		classes[1] = ata_sff_dev_classify(&link->device[1],
1953						  devmask & (1 << 1), &err);
1954
1955	return 0;
1956}
1957EXPORT_SYMBOL_GPL(ata_sff_softreset);
1958
1959/**
1960 *	sata_sff_hardreset - reset host port via SATA phy reset
1961 *	@link: link to reset
1962 *	@class: resulting class of attached device
1963 *	@deadline: deadline jiffies for the operation
1964 *
1965 *	SATA phy-reset host port using DET bits of SControl register,
1966 *	wait for !BSY and classify the attached device.
1967 *
1968 *	LOCKING:
1969 *	Kernel thread context (may sleep)
1970 *
1971 *	RETURNS:
1972 *	0 on success, -errno otherwise.
1973 */
1974int sata_sff_hardreset(struct ata_link *link, unsigned int *class,
1975		       unsigned long deadline)
1976{
1977	struct ata_eh_context *ehc = &link->eh_context;
1978	const unsigned long *timing = sata_ehc_deb_timing(ehc);
1979	bool online;
1980	int rc;
1981
1982	rc = sata_link_hardreset(link, timing, deadline, &online,
1983				 ata_sff_check_ready);
1984	if (online)
1985		*class = ata_sff_dev_classify(link->device, 1, NULL);
1986
1987	return rc;
1988}
1989EXPORT_SYMBOL_GPL(sata_sff_hardreset);
1990
1991/**
1992 *	ata_sff_postreset - SFF postreset callback
1993 *	@link: the target SFF ata_link
1994 *	@classes: classes of attached devices
1995 *
1996 *	This function is invoked after a successful reset.  It first
1997 *	calls ata_std_postreset() and performs SFF specific postreset
1998 *	processing.
1999 *
2000 *	LOCKING:
2001 *	Kernel thread context (may sleep)
2002 */
2003void ata_sff_postreset(struct ata_link *link, unsigned int *classes)
2004{
2005	struct ata_port *ap = link->ap;
2006
2007	ata_std_postreset(link, classes);
2008
2009	/* is double-select really necessary? */
2010	if (classes[0] != ATA_DEV_NONE)
2011		ap->ops->sff_dev_select(ap, 1);
2012	if (classes[1] != ATA_DEV_NONE)
2013		ap->ops->sff_dev_select(ap, 0);
2014
2015	/* bail out if no device is present */
2016	if (classes[0] == ATA_DEV_NONE && classes[1] == ATA_DEV_NONE)
2017		return;
2018
2019	/* set up device control */
2020	if (ata_sff_set_devctl(ap, ap->ctl))
2021		ap->last_ctl = ap->ctl;
2022}
2023EXPORT_SYMBOL_GPL(ata_sff_postreset);
2024
2025/**
2026 *	ata_sff_drain_fifo - Stock FIFO drain logic for SFF controllers
2027 *	@qc: command
2028 *
2029 *	Drain the FIFO and device of any stuck data following a command
2030 *	failing to complete. In some cases this is necessary before a
2031 *	reset will recover the device.
2032 *
2033 */
2034
2035void ata_sff_drain_fifo(struct ata_queued_cmd *qc)
2036{
2037	int count;
2038	struct ata_port *ap;
2039
2040	/* We only need to flush incoming data when a command was running */
2041	if (qc == NULL || qc->dma_dir == DMA_TO_DEVICE)
2042		return;
2043
2044	ap = qc->ap;
2045	/* Drain up to 64K of data before we give up this recovery method */
2046	for (count = 0; (ap->ops->sff_check_status(ap) & ATA_DRQ)
2047						&& count < 65536; count += 2)
2048		ioread16(ap->ioaddr.data_addr);
2049
2050	if (count)
2051		ata_port_dbg(ap, "drained %d bytes to clear DRQ\n", count);
2052
2053}
2054EXPORT_SYMBOL_GPL(ata_sff_drain_fifo);
2055
2056/**
2057 *	ata_sff_error_handler - Stock error handler for SFF controller
2058 *	@ap: port to handle error for
2059 *
2060 *	Stock error handler for SFF controller.  It can handle both
2061 *	PATA and SATA controllers.  Many controllers should be able to
2062 *	use this EH as-is or with some added handling before and
2063 *	after.
2064 *
2065 *	LOCKING:
2066 *	Kernel thread context (may sleep)
2067 */
2068void ata_sff_error_handler(struct ata_port *ap)
2069{
2070	ata_reset_fn_t softreset = ap->ops->softreset;
2071	ata_reset_fn_t hardreset = ap->ops->hardreset;
2072	struct ata_queued_cmd *qc;
2073	unsigned long flags;
2074
2075	qc = __ata_qc_from_tag(ap, ap->link.active_tag);
2076	if (qc && !(qc->flags & ATA_QCFLAG_FAILED))
2077		qc = NULL;
2078
2079	spin_lock_irqsave(ap->lock, flags);
2080
2081	/*
2082	 * We *MUST* do FIFO draining before we issue a reset as
2083	 * several devices helpfully clear their internal state and
2084	 * will lock solid if we touch the data port post reset. Pass
2085	 * qc in case anyone wants to do different PIO/DMA recovery or
2086	 * has per command fixups
2087	 */
2088	if (ap->ops->sff_drain_fifo)
2089		ap->ops->sff_drain_fifo(qc);
2090
2091	spin_unlock_irqrestore(ap->lock, flags);
2092
2093	/* ignore built-in hardresets if SCR access is not available */
2094	if ((hardreset == sata_std_hardreset ||
2095	     hardreset == sata_sff_hardreset) && !sata_scr_valid(&ap->link))
2096		hardreset = NULL;
2097
2098	ata_do_eh(ap, ap->ops->prereset, softreset, hardreset,
2099		  ap->ops->postreset);
2100}
2101EXPORT_SYMBOL_GPL(ata_sff_error_handler);
2102
2103/**
2104 *	ata_sff_std_ports - initialize ioaddr with standard port offsets.
2105 *	@ioaddr: IO address structure to be initialized
2106 *
2107 *	Utility function which initializes data_addr, error_addr,
2108 *	feature_addr, nsect_addr, lbal_addr, lbam_addr, lbah_addr,
2109 *	device_addr, status_addr, and command_addr to standard offsets
2110 *	relative to cmd_addr.
2111 *
2112 *	Does not set ctl_addr, altstatus_addr, bmdma_addr, or scr_addr.
2113 */
2114void ata_sff_std_ports(struct ata_ioports *ioaddr)
2115{
2116	ioaddr->data_addr = ioaddr->cmd_addr + ATA_REG_DATA;
2117	ioaddr->error_addr = ioaddr->cmd_addr + ATA_REG_ERR;
2118	ioaddr->feature_addr = ioaddr->cmd_addr + ATA_REG_FEATURE;
2119	ioaddr->nsect_addr = ioaddr->cmd_addr + ATA_REG_NSECT;
2120	ioaddr->lbal_addr = ioaddr->cmd_addr + ATA_REG_LBAL;
2121	ioaddr->lbam_addr = ioaddr->cmd_addr + ATA_REG_LBAM;
2122	ioaddr->lbah_addr = ioaddr->cmd_addr + ATA_REG_LBAH;
2123	ioaddr->device_addr = ioaddr->cmd_addr + ATA_REG_DEVICE;
2124	ioaddr->status_addr = ioaddr->cmd_addr + ATA_REG_STATUS;
2125	ioaddr->command_addr = ioaddr->cmd_addr + ATA_REG_CMD;
2126}
2127EXPORT_SYMBOL_GPL(ata_sff_std_ports);
2128
2129#ifdef CONFIG_PCI
2130
2131static bool ata_resources_present(struct pci_dev *pdev, int port)
2132{
2133	int i;
2134
2135	/* Check the PCI resources for this channel are enabled */
2136	port *= 2;
2137	for (i = 0; i < 2; i++) {
2138		if (pci_resource_start(pdev, port + i) == 0 ||
2139		    pci_resource_len(pdev, port + i) == 0)
2140			return false;
2141	}
2142	return true;
2143}
2144
2145/**
2146 *	ata_pci_sff_init_host - acquire native PCI ATA resources and init host
2147 *	@host: target ATA host
2148 *
2149 *	Acquire native PCI ATA resources for @host and initialize the
2150 *	first two ports of @host accordingly.  Ports marked dummy are
2151 *	skipped and allocation failure makes the port dummy.
2152 *
2153 *	Note that native PCI resources are valid even for legacy hosts
2154 *	as we fix up pdev resources array early in boot, so this
2155 *	function can be used for both native and legacy SFF hosts.
2156 *
2157 *	LOCKING:
2158 *	Inherited from calling layer (may sleep).
2159 *
2160 *	RETURNS:
2161 *	0 if at least one port is initialized, -ENODEV if no port is
2162 *	available.
2163 */
2164int ata_pci_sff_init_host(struct ata_host *host)
2165{
2166	struct device *gdev = host->dev;
2167	struct pci_dev *pdev = to_pci_dev(gdev);
2168	unsigned int mask = 0;
2169	int i, rc;
2170
2171	/* request, iomap BARs and init port addresses accordingly */
2172	for (i = 0; i < 2; i++) {
2173		struct ata_port *ap = host->ports[i];
2174		int base = i * 2;
2175		void __iomem * const *iomap;
2176
2177		if (ata_port_is_dummy(ap))
2178			continue;
2179
2180		/* Discard disabled ports.  Some controllers show
2181		 * their unused channels this way.  Disabled ports are
2182		 * made dummy.
2183		 */
2184		if (!ata_resources_present(pdev, i)) {
2185			ap->ops = &ata_dummy_port_ops;
2186			continue;
2187		}
2188
2189		rc = pcim_iomap_regions(pdev, 0x3 << base,
2190					dev_driver_string(gdev));
2191		if (rc) {
2192			dev_warn(gdev,
2193				 "failed to request/iomap BARs for port %d (errno=%d)\n",
2194				 i, rc);
2195			if (rc == -EBUSY)
2196				pcim_pin_device(pdev);
2197			ap->ops = &ata_dummy_port_ops;
2198			continue;
2199		}
2200		host->iomap = iomap = pcim_iomap_table(pdev);
2201
2202		ap->ioaddr.cmd_addr = iomap[base];
2203		ap->ioaddr.altstatus_addr =
2204		ap->ioaddr.ctl_addr = (void __iomem *)
2205			((unsigned long)iomap[base + 1] | ATA_PCI_CTL_OFS);
2206		ata_sff_std_ports(&ap->ioaddr);
2207
2208		ata_port_desc(ap, "cmd 0x%llx ctl 0x%llx",
2209			(unsigned long long)pci_resource_start(pdev, base),
2210			(unsigned long long)pci_resource_start(pdev, base + 1));
2211
2212		mask |= 1 << i;
2213	}
2214
2215	if (!mask) {
2216		dev_err(gdev, "no available native port\n");
2217		return -ENODEV;
2218	}
2219
2220	return 0;
2221}
2222EXPORT_SYMBOL_GPL(ata_pci_sff_init_host);
2223
2224/**
2225 *	ata_pci_sff_prepare_host - helper to prepare PCI PIO-only SFF ATA host
2226 *	@pdev: target PCI device
2227 *	@ppi: array of port_info, must be enough for two ports
2228 *	@r_host: out argument for the initialized ATA host
2229 *
2230 *	Helper to allocate PIO-only SFF ATA host for @pdev, acquire
2231 *	all PCI resources and initialize it accordingly in one go.
2232 *
2233 *	LOCKING:
2234 *	Inherited from calling layer (may sleep).
2235 *
2236 *	RETURNS:
2237 *	0 on success, -errno otherwise.
2238 */
2239int ata_pci_sff_prepare_host(struct pci_dev *pdev,
2240			     const struct ata_port_info * const *ppi,
2241			     struct ata_host **r_host)
2242{
2243	struct ata_host *host;
2244	int rc;
2245
2246	if (!devres_open_group(&pdev->dev, NULL, GFP_KERNEL))
2247		return -ENOMEM;
2248
2249	host = ata_host_alloc_pinfo(&pdev->dev, ppi, 2);
2250	if (!host) {
2251		dev_err(&pdev->dev, "failed to allocate ATA host\n");
2252		rc = -ENOMEM;
2253		goto err_out;
2254	}
2255
2256	rc = ata_pci_sff_init_host(host);
2257	if (rc)
2258		goto err_out;
2259
2260	devres_remove_group(&pdev->dev, NULL);
2261	*r_host = host;
2262	return 0;
2263
2264err_out:
2265	devres_release_group(&pdev->dev, NULL);
2266	return rc;
2267}
2268EXPORT_SYMBOL_GPL(ata_pci_sff_prepare_host);
2269
2270/**
2271 *	ata_pci_sff_activate_host - start SFF host, request IRQ and register it
2272 *	@host: target SFF ATA host
2273 *	@irq_handler: irq_handler used when requesting IRQ(s)
2274 *	@sht: scsi_host_template to use when registering the host
2275 *
2276 *	This is the counterpart of ata_host_activate() for SFF ATA
2277 *	hosts.  This separate helper is necessary because SFF hosts
2278 *	use two separate interrupts in legacy mode.
2279 *
2280 *	LOCKING:
2281 *	Inherited from calling layer (may sleep).
2282 *
2283 *	RETURNS:
2284 *	0 on success, -errno otherwise.
2285 */
2286int ata_pci_sff_activate_host(struct ata_host *host,
2287			      irq_handler_t irq_handler,
2288			      struct scsi_host_template *sht)
2289{
2290	struct device *dev = host->dev;
2291	struct pci_dev *pdev = to_pci_dev(dev);
2292	const char *drv_name = dev_driver_string(host->dev);
2293	int legacy_mode = 0, rc;
2294
2295	rc = ata_host_start(host);
2296	if (rc)
2297		return rc;
2298
2299	if ((pdev->class >> 8) == PCI_CLASS_STORAGE_IDE) {
2300		u8 tmp8, mask = 0;
2301
2302		/*
2303		 * ATA spec says we should use legacy mode when one
2304		 * port is in legacy mode, but disabled ports on some
2305		 * PCI hosts appear as fixed legacy ports, e.g SB600/700
2306		 * on which the secondary port is not wired, so
2307		 * ignore ports that are marked as 'dummy' during
2308		 * this check
2309		 */
2310		pci_read_config_byte(pdev, PCI_CLASS_PROG, &tmp8);
2311		if (!ata_port_is_dummy(host->ports[0]))
2312			mask |= (1 << 0);
2313		if (!ata_port_is_dummy(host->ports[1]))
2314			mask |= (1 << 2);
2315		if ((tmp8 & mask) != mask)
2316			legacy_mode = 1;
2317	}
2318
2319	if (!devres_open_group(dev, NULL, GFP_KERNEL))
2320		return -ENOMEM;
2321
2322	if (!legacy_mode && pdev->irq) {
2323		int i;
2324
2325		rc = devm_request_irq(dev, pdev->irq, irq_handler,
2326				      IRQF_SHARED, drv_name, host);
2327		if (rc)
2328			goto out;
2329
2330		for (i = 0; i < 2; i++) {
2331			if (ata_port_is_dummy(host->ports[i]))
2332				continue;
2333			ata_port_desc(host->ports[i], "irq %d", pdev->irq);
2334		}
2335	} else if (legacy_mode) {
2336		if (!ata_port_is_dummy(host->ports[0])) {
2337			rc = devm_request_irq(dev, ATA_PRIMARY_IRQ(pdev),
2338					      irq_handler, IRQF_SHARED,
2339					      drv_name, host);
2340			if (rc)
2341				goto out;
2342
2343			ata_port_desc(host->ports[0], "irq %d",
2344				      ATA_PRIMARY_IRQ(pdev));
2345		}
2346
2347		if (!ata_port_is_dummy(host->ports[1])) {
2348			rc = devm_request_irq(dev, ATA_SECONDARY_IRQ(pdev),
2349					      irq_handler, IRQF_SHARED,
2350					      drv_name, host);
2351			if (rc)
2352				goto out;
2353
2354			ata_port_desc(host->ports[1], "irq %d",
2355				      ATA_SECONDARY_IRQ(pdev));
2356		}
2357	}
2358
2359	rc = ata_host_register(host, sht);
2360out:
2361	if (rc == 0)
2362		devres_remove_group(dev, NULL);
2363	else
2364		devres_release_group(dev, NULL);
2365
2366	return rc;
2367}
2368EXPORT_SYMBOL_GPL(ata_pci_sff_activate_host);
2369
2370static const struct ata_port_info *ata_sff_find_valid_pi(
2371					const struct ata_port_info * const *ppi)
2372{
2373	int i;
2374
2375	/* look up the first valid port_info */
2376	for (i = 0; i < 2 && ppi[i]; i++)
2377		if (ppi[i]->port_ops != &ata_dummy_port_ops)
2378			return ppi[i];
2379
2380	return NULL;
2381}
2382
2383static int ata_pci_init_one(struct pci_dev *pdev,
2384		const struct ata_port_info * const *ppi,
2385		struct scsi_host_template *sht, void *host_priv,
2386		int hflags, bool bmdma)
2387{
2388	struct device *dev = &pdev->dev;
2389	const struct ata_port_info *pi;
2390	struct ata_host *host = NULL;
2391	int rc;
2392
2393	pi = ata_sff_find_valid_pi(ppi);
2394	if (!pi) {
2395		dev_err(&pdev->dev, "no valid port_info specified\n");
2396		return -EINVAL;
2397	}
2398
2399	if (!devres_open_group(dev, NULL, GFP_KERNEL))
2400		return -ENOMEM;
2401
2402	rc = pcim_enable_device(pdev);
2403	if (rc)
2404		goto out;
2405
2406#ifdef CONFIG_ATA_BMDMA
2407	if (bmdma)
2408		/* prepare and activate BMDMA host */
2409		rc = ata_pci_bmdma_prepare_host(pdev, ppi, &host);
2410	else
2411#endif
2412		/* prepare and activate SFF host */
2413		rc = ata_pci_sff_prepare_host(pdev, ppi, &host);
2414	if (rc)
2415		goto out;
2416	host->private_data = host_priv;
2417	host->flags |= hflags;
2418
2419#ifdef CONFIG_ATA_BMDMA
2420	if (bmdma) {
2421		pci_set_master(pdev);
2422		rc = ata_pci_sff_activate_host(host, ata_bmdma_interrupt, sht);
2423	} else
2424#endif
2425		rc = ata_pci_sff_activate_host(host, ata_sff_interrupt, sht);
2426out:
2427	if (rc == 0)
2428		devres_remove_group(&pdev->dev, NULL);
2429	else
2430		devres_release_group(&pdev->dev, NULL);
2431
2432	return rc;
2433}
2434
2435/**
2436 *	ata_pci_sff_init_one - Initialize/register PIO-only PCI IDE controller
2437 *	@pdev: Controller to be initialized
2438 *	@ppi: array of port_info, must be enough for two ports
2439 *	@sht: scsi_host_template to use when registering the host
2440 *	@host_priv: host private_data
2441 *	@hflag: host flags
2442 *
2443 *	This is a helper function which can be called from a driver's
2444 *	xxx_init_one() probe function if the hardware uses traditional
2445 *	IDE taskfile registers and is PIO only.
2446 *
2447 *	ASSUMPTION:
2448 *	Nobody makes a single channel controller that appears solely as
2449 *	the secondary legacy port on PCI.
2450 *
2451 *	LOCKING:
2452 *	Inherited from PCI layer (may sleep).
2453 *
2454 *	RETURNS:
2455 *	Zero on success, negative on errno-based value on error.
2456 */
2457int ata_pci_sff_init_one(struct pci_dev *pdev,
2458		 const struct ata_port_info * const *ppi,
2459		 struct scsi_host_template *sht, void *host_priv, int hflag)
2460{
2461	return ata_pci_init_one(pdev, ppi, sht, host_priv, hflag, 0);
2462}
2463EXPORT_SYMBOL_GPL(ata_pci_sff_init_one);
2464
2465#endif /* CONFIG_PCI */
2466
2467/*
2468 *	BMDMA support
2469 */
2470
2471#ifdef CONFIG_ATA_BMDMA
2472
2473const struct ata_port_operations ata_bmdma_port_ops = {
2474	.inherits		= &ata_sff_port_ops,
2475
2476	.error_handler		= ata_bmdma_error_handler,
2477	.post_internal_cmd	= ata_bmdma_post_internal_cmd,
2478
2479	.qc_prep		= ata_bmdma_qc_prep,
2480	.qc_issue		= ata_bmdma_qc_issue,
2481
2482	.sff_irq_clear		= ata_bmdma_irq_clear,
2483	.bmdma_setup		= ata_bmdma_setup,
2484	.bmdma_start		= ata_bmdma_start,
2485	.bmdma_stop		= ata_bmdma_stop,
2486	.bmdma_status		= ata_bmdma_status,
2487
2488	.port_start		= ata_bmdma_port_start,
2489};
2490EXPORT_SYMBOL_GPL(ata_bmdma_port_ops);
2491
2492const struct ata_port_operations ata_bmdma32_port_ops = {
2493	.inherits		= &ata_bmdma_port_ops,
2494
2495	.sff_data_xfer		= ata_sff_data_xfer32,
2496	.port_start		= ata_bmdma_port_start32,
2497};
2498EXPORT_SYMBOL_GPL(ata_bmdma32_port_ops);
2499
2500/**
2501 *	ata_bmdma_fill_sg - Fill PCI IDE PRD table
2502 *	@qc: Metadata associated with taskfile to be transferred
2503 *
2504 *	Fill PCI IDE PRD (scatter-gather) table with segments
2505 *	associated with the current disk command.
2506 *
2507 *	LOCKING:
2508 *	spin_lock_irqsave(host lock)
2509 *
2510 */
2511static void ata_bmdma_fill_sg(struct ata_queued_cmd *qc)
2512{
2513	struct ata_port *ap = qc->ap;
2514	struct ata_bmdma_prd *prd = ap->bmdma_prd;
2515	struct scatterlist *sg;
2516	unsigned int si, pi;
2517
2518	pi = 0;
2519	for_each_sg(qc->sg, sg, qc->n_elem, si) {
2520		u32 addr, offset;
2521		u32 sg_len, len;
2522
2523		/* determine if physical DMA addr spans 64K boundary.
2524		 * Note h/w doesn't support 64-bit, so we unconditionally
2525		 * truncate dma_addr_t to u32.
2526		 */
2527		addr = (u32) sg_dma_address(sg);
2528		sg_len = sg_dma_len(sg);
2529
2530		while (sg_len) {
2531			offset = addr & 0xffff;
2532			len = sg_len;
2533			if ((offset + sg_len) > 0x10000)
2534				len = 0x10000 - offset;
2535
2536			prd[pi].addr = cpu_to_le32(addr);
2537			prd[pi].flags_len = cpu_to_le32(len & 0xffff);
2538
2539			pi++;
2540			sg_len -= len;
2541			addr += len;
2542		}
2543	}
2544
2545	prd[pi - 1].flags_len |= cpu_to_le32(ATA_PRD_EOT);
2546}
2547
2548/**
2549 *	ata_bmdma_fill_sg_dumb - Fill PCI IDE PRD table
2550 *	@qc: Metadata associated with taskfile to be transferred
2551 *
2552 *	Fill PCI IDE PRD (scatter-gather) table with segments
2553 *	associated with the current disk command. Perform the fill
2554 *	so that we avoid writing any length 64K records for
2555 *	controllers that don't follow the spec.
2556 *
2557 *	LOCKING:
2558 *	spin_lock_irqsave(host lock)
2559 *
2560 */
2561static void ata_bmdma_fill_sg_dumb(struct ata_queued_cmd *qc)
2562{
2563	struct ata_port *ap = qc->ap;
2564	struct ata_bmdma_prd *prd = ap->bmdma_prd;
2565	struct scatterlist *sg;
2566	unsigned int si, pi;
2567
2568	pi = 0;
2569	for_each_sg(qc->sg, sg, qc->n_elem, si) {
2570		u32 addr, offset;
2571		u32 sg_len, len, blen;
2572
2573		/* determine if physical DMA addr spans 64K boundary.
2574		 * Note h/w doesn't support 64-bit, so we unconditionally
2575		 * truncate dma_addr_t to u32.
2576		 */
2577		addr = (u32) sg_dma_address(sg);
2578		sg_len = sg_dma_len(sg);
2579
2580		while (sg_len) {
2581			offset = addr & 0xffff;
2582			len = sg_len;
2583			if ((offset + sg_len) > 0x10000)
2584				len = 0x10000 - offset;
2585
2586			blen = len & 0xffff;
2587			prd[pi].addr = cpu_to_le32(addr);
2588			if (blen == 0) {
2589				/* Some PATA chipsets like the CS5530 can't
2590				   cope with 0x0000 meaning 64K as the spec
2591				   says */
2592				prd[pi].flags_len = cpu_to_le32(0x8000);
2593				blen = 0x8000;
2594				prd[++pi].addr = cpu_to_le32(addr + 0x8000);
2595			}
2596			prd[pi].flags_len = cpu_to_le32(blen);
2597
2598			pi++;
2599			sg_len -= len;
2600			addr += len;
2601		}
2602	}
2603
2604	prd[pi - 1].flags_len |= cpu_to_le32(ATA_PRD_EOT);
2605}
2606
2607/**
2608 *	ata_bmdma_qc_prep - Prepare taskfile for submission
2609 *	@qc: Metadata associated with taskfile to be prepared
2610 *
2611 *	Prepare ATA taskfile for submission.
2612 *
2613 *	LOCKING:
2614 *	spin_lock_irqsave(host lock)
2615 */
2616enum ata_completion_errors ata_bmdma_qc_prep(struct ata_queued_cmd *qc)
2617{
2618	if (!(qc->flags & ATA_QCFLAG_DMAMAP))
2619		return AC_ERR_OK;
2620
2621	ata_bmdma_fill_sg(qc);
2622
2623	return AC_ERR_OK;
2624}
2625EXPORT_SYMBOL_GPL(ata_bmdma_qc_prep);
2626
2627/**
2628 *	ata_bmdma_dumb_qc_prep - Prepare taskfile for submission
2629 *	@qc: Metadata associated with taskfile to be prepared
2630 *
2631 *	Prepare ATA taskfile for submission.
2632 *
2633 *	LOCKING:
2634 *	spin_lock_irqsave(host lock)
2635 */
2636enum ata_completion_errors ata_bmdma_dumb_qc_prep(struct ata_queued_cmd *qc)
2637{
2638	if (!(qc->flags & ATA_QCFLAG_DMAMAP))
2639		return AC_ERR_OK;
2640
2641	ata_bmdma_fill_sg_dumb(qc);
2642
2643	return AC_ERR_OK;
2644}
2645EXPORT_SYMBOL_GPL(ata_bmdma_dumb_qc_prep);
2646
2647/**
2648 *	ata_bmdma_qc_issue - issue taskfile to a BMDMA controller
2649 *	@qc: command to issue to device
2650 *
2651 *	This function issues a PIO, NODATA or DMA command to a
2652 *	SFF/BMDMA controller.  PIO and NODATA are handled by
2653 *	ata_sff_qc_issue().
2654 *
2655 *	LOCKING:
2656 *	spin_lock_irqsave(host lock)
2657 *
2658 *	RETURNS:
2659 *	Zero on success, AC_ERR_* mask on failure
2660 */
2661unsigned int ata_bmdma_qc_issue(struct ata_queued_cmd *qc)
2662{
2663	struct ata_port *ap = qc->ap;
2664	struct ata_link *link = qc->dev->link;
2665
2666	/* defer PIO handling to sff_qc_issue */
2667	if (!ata_is_dma(qc->tf.protocol))
2668		return ata_sff_qc_issue(qc);
2669
2670	/* select the device */
2671	ata_dev_select(ap, qc->dev->devno, 1, 0);
2672
2673	/* start the command */
2674	switch (qc->tf.protocol) {
2675	case ATA_PROT_DMA:
2676		WARN_ON_ONCE(qc->tf.flags & ATA_TFLAG_POLLING);
2677
2678		trace_ata_tf_load(ap, &qc->tf);
2679		ap->ops->sff_tf_load(ap, &qc->tf);  /* load tf registers */
2680		trace_ata_bmdma_setup(ap, &qc->tf, qc->tag);
2681		ap->ops->bmdma_setup(qc);	    /* set up bmdma */
2682		trace_ata_bmdma_start(ap, &qc->tf, qc->tag);
2683		ap->ops->bmdma_start(qc);	    /* initiate bmdma */
2684		ap->hsm_task_state = HSM_ST_LAST;
2685		break;
2686
2687	case ATAPI_PROT_DMA:
2688		WARN_ON_ONCE(qc->tf.flags & ATA_TFLAG_POLLING);
2689
2690		trace_ata_tf_load(ap, &qc->tf);
2691		ap->ops->sff_tf_load(ap, &qc->tf);  /* load tf registers */
2692		trace_ata_bmdma_setup(ap, &qc->tf, qc->tag);
2693		ap->ops->bmdma_setup(qc);	    /* set up bmdma */
2694		ap->hsm_task_state = HSM_ST_FIRST;
2695
2696		/* send cdb by polling if no cdb interrupt */
2697		if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
2698			ata_sff_queue_pio_task(link, 0);
2699		break;
2700
2701	default:
2702		WARN_ON(1);
2703		return AC_ERR_SYSTEM;
2704	}
2705
2706	return 0;
2707}
2708EXPORT_SYMBOL_GPL(ata_bmdma_qc_issue);
2709
2710/**
2711 *	ata_bmdma_port_intr - Handle BMDMA port interrupt
2712 *	@ap: Port on which interrupt arrived (possibly...)
2713 *	@qc: Taskfile currently active in engine
2714 *
2715 *	Handle port interrupt for given queued command.
2716 *
2717 *	LOCKING:
2718 *	spin_lock_irqsave(host lock)
2719 *
2720 *	RETURNS:
2721 *	One if interrupt was handled, zero if not (shared irq).
2722 */
2723unsigned int ata_bmdma_port_intr(struct ata_port *ap, struct ata_queued_cmd *qc)
2724{
2725	struct ata_eh_info *ehi = &ap->link.eh_info;
2726	u8 host_stat = 0;
2727	bool bmdma_stopped = false;
2728	unsigned int handled;
2729
2730	if (ap->hsm_task_state == HSM_ST_LAST && ata_is_dma(qc->tf.protocol)) {
2731		/* check status of DMA engine */
2732		host_stat = ap->ops->bmdma_status(ap);
2733		trace_ata_bmdma_status(ap, host_stat);
2734
2735		/* if it's not our irq... */
2736		if (!(host_stat & ATA_DMA_INTR))
2737			return ata_sff_idle_irq(ap);
2738
2739		/* before we do anything else, clear DMA-Start bit */
2740		trace_ata_bmdma_stop(ap, &qc->tf, qc->tag);
2741		ap->ops->bmdma_stop(qc);
2742		bmdma_stopped = true;
2743
2744		if (unlikely(host_stat & ATA_DMA_ERR)) {
2745			/* error when transferring data to/from memory */
2746			qc->err_mask |= AC_ERR_HOST_BUS;
2747			ap->hsm_task_state = HSM_ST_ERR;
2748		}
2749	}
2750
2751	handled = __ata_sff_port_intr(ap, qc, bmdma_stopped);
2752
2753	if (unlikely(qc->err_mask) && ata_is_dma(qc->tf.protocol))
2754		ata_ehi_push_desc(ehi, "BMDMA stat 0x%x", host_stat);
2755
2756	return handled;
2757}
2758EXPORT_SYMBOL_GPL(ata_bmdma_port_intr);
2759
2760/**
2761 *	ata_bmdma_interrupt - Default BMDMA ATA host interrupt handler
2762 *	@irq: irq line (unused)
2763 *	@dev_instance: pointer to our ata_host information structure
2764 *
2765 *	Default interrupt handler for PCI IDE devices.  Calls
2766 *	ata_bmdma_port_intr() for each port that is not disabled.
2767 *
2768 *	LOCKING:
2769 *	Obtains host lock during operation.
2770 *
2771 *	RETURNS:
2772 *	IRQ_NONE or IRQ_HANDLED.
2773 */
2774irqreturn_t ata_bmdma_interrupt(int irq, void *dev_instance)
2775{
2776	return __ata_sff_interrupt(irq, dev_instance, ata_bmdma_port_intr);
2777}
2778EXPORT_SYMBOL_GPL(ata_bmdma_interrupt);
2779
2780/**
2781 *	ata_bmdma_error_handler - Stock error handler for BMDMA controller
2782 *	@ap: port to handle error for
2783 *
2784 *	Stock error handler for BMDMA controller.  It can handle both
2785 *	PATA and SATA controllers.  Most BMDMA controllers should be
2786 *	able to use this EH as-is or with some added handling before
2787 *	and after.
2788 *
2789 *	LOCKING:
2790 *	Kernel thread context (may sleep)
2791 */
2792void ata_bmdma_error_handler(struct ata_port *ap)
2793{
2794	struct ata_queued_cmd *qc;
2795	unsigned long flags;
2796	bool thaw = false;
2797
2798	qc = __ata_qc_from_tag(ap, ap->link.active_tag);
2799	if (qc && !(qc->flags & ATA_QCFLAG_FAILED))
2800		qc = NULL;
2801
2802	/* reset PIO HSM and stop DMA engine */
2803	spin_lock_irqsave(ap->lock, flags);
2804
2805	if (qc && ata_is_dma(qc->tf.protocol)) {
2806		u8 host_stat;
2807
2808		host_stat = ap->ops->bmdma_status(ap);
2809		trace_ata_bmdma_status(ap, host_stat);
2810
2811		/* BMDMA controllers indicate host bus error by
2812		 * setting DMA_ERR bit and timing out.  As it wasn't
2813		 * really a timeout event, adjust error mask and
2814		 * cancel frozen state.
2815		 */
2816		if (qc->err_mask == AC_ERR_TIMEOUT && (host_stat & ATA_DMA_ERR)) {
2817			qc->err_mask = AC_ERR_HOST_BUS;
2818			thaw = true;
2819		}
2820
2821		trace_ata_bmdma_stop(ap, &qc->tf, qc->tag);
2822		ap->ops->bmdma_stop(qc);
2823
2824		/* if we're gonna thaw, make sure IRQ is clear */
2825		if (thaw) {
2826			ap->ops->sff_check_status(ap);
2827			if (ap->ops->sff_irq_clear)
2828				ap->ops->sff_irq_clear(ap);
2829		}
2830	}
2831
2832	spin_unlock_irqrestore(ap->lock, flags);
2833
2834	if (thaw)
2835		ata_eh_thaw_port(ap);
2836
2837	ata_sff_error_handler(ap);
2838}
2839EXPORT_SYMBOL_GPL(ata_bmdma_error_handler);
2840
2841/**
2842 *	ata_bmdma_post_internal_cmd - Stock post_internal_cmd for BMDMA
2843 *	@qc: internal command to clean up
2844 *
2845 *	LOCKING:
2846 *	Kernel thread context (may sleep)
2847 */
2848void ata_bmdma_post_internal_cmd(struct ata_queued_cmd *qc)
2849{
2850	struct ata_port *ap = qc->ap;
2851	unsigned long flags;
2852
2853	if (ata_is_dma(qc->tf.protocol)) {
2854		spin_lock_irqsave(ap->lock, flags);
2855		trace_ata_bmdma_stop(ap, &qc->tf, qc->tag);
2856		ap->ops->bmdma_stop(qc);
2857		spin_unlock_irqrestore(ap->lock, flags);
2858	}
2859}
2860EXPORT_SYMBOL_GPL(ata_bmdma_post_internal_cmd);
2861
2862/**
2863 *	ata_bmdma_irq_clear - Clear PCI IDE BMDMA interrupt.
2864 *	@ap: Port associated with this ATA transaction.
2865 *
2866 *	Clear interrupt and error flags in DMA status register.
2867 *
2868 *	May be used as the irq_clear() entry in ata_port_operations.
2869 *
2870 *	LOCKING:
2871 *	spin_lock_irqsave(host lock)
2872 */
2873void ata_bmdma_irq_clear(struct ata_port *ap)
2874{
2875	void __iomem *mmio = ap->ioaddr.bmdma_addr;
2876
2877	if (!mmio)
2878		return;
2879
2880	iowrite8(ioread8(mmio + ATA_DMA_STATUS), mmio + ATA_DMA_STATUS);
2881}
2882EXPORT_SYMBOL_GPL(ata_bmdma_irq_clear);
2883
2884/**
2885 *	ata_bmdma_setup - Set up PCI IDE BMDMA transaction
2886 *	@qc: Info associated with this ATA transaction.
2887 *
2888 *	LOCKING:
2889 *	spin_lock_irqsave(host lock)
2890 */
2891void ata_bmdma_setup(struct ata_queued_cmd *qc)
2892{
2893	struct ata_port *ap = qc->ap;
2894	unsigned int rw = (qc->tf.flags & ATA_TFLAG_WRITE);
2895	u8 dmactl;
2896
2897	/* load PRD table addr. */
2898	mb();	/* make sure PRD table writes are visible to controller */
2899	iowrite32(ap->bmdma_prd_dma, ap->ioaddr.bmdma_addr + ATA_DMA_TABLE_OFS);
2900
2901	/* specify data direction, triple-check start bit is clear */
2902	dmactl = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
2903	dmactl &= ~(ATA_DMA_WR | ATA_DMA_START);
2904	if (!rw)
2905		dmactl |= ATA_DMA_WR;
2906	iowrite8(dmactl, ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
2907
2908	/* issue r/w command */
2909	ap->ops->sff_exec_command(ap, &qc->tf);
2910}
2911EXPORT_SYMBOL_GPL(ata_bmdma_setup);
2912
2913/**
2914 *	ata_bmdma_start - Start a PCI IDE BMDMA transaction
2915 *	@qc: Info associated with this ATA transaction.
2916 *
2917 *	LOCKING:
2918 *	spin_lock_irqsave(host lock)
2919 */
2920void ata_bmdma_start(struct ata_queued_cmd *qc)
2921{
2922	struct ata_port *ap = qc->ap;
2923	u8 dmactl;
2924
2925	/* start host DMA transaction */
2926	dmactl = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
2927	iowrite8(dmactl | ATA_DMA_START, ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
2928
2929	/* Strictly, one may wish to issue an ioread8() here, to
2930	 * flush the mmio write.  However, control also passes
2931	 * to the hardware at this point, and it will interrupt
2932	 * us when we are to resume control.  So, in effect,
2933	 * we don't care when the mmio write flushes.
2934	 * Further, a read of the DMA status register _immediately_
2935	 * following the write may not be what certain flaky hardware
2936	 * is expected, so I think it is best to not add a readb()
2937	 * without first all the MMIO ATA cards/mobos.
2938	 * Or maybe I'm just being paranoid.
2939	 *
2940	 * FIXME: The posting of this write means I/O starts are
2941	 * unnecessarily delayed for MMIO
2942	 */
2943}
2944EXPORT_SYMBOL_GPL(ata_bmdma_start);
2945
2946/**
2947 *	ata_bmdma_stop - Stop PCI IDE BMDMA transfer
2948 *	@qc: Command we are ending DMA for
2949 *
2950 *	Clears the ATA_DMA_START flag in the dma control register
2951 *
2952 *	May be used as the bmdma_stop() entry in ata_port_operations.
2953 *
2954 *	LOCKING:
2955 *	spin_lock_irqsave(host lock)
2956 */
2957void ata_bmdma_stop(struct ata_queued_cmd *qc)
2958{
2959	struct ata_port *ap = qc->ap;
2960	void __iomem *mmio = ap->ioaddr.bmdma_addr;
2961
2962	/* clear start/stop bit */
2963	iowrite8(ioread8(mmio + ATA_DMA_CMD) & ~ATA_DMA_START,
2964		 mmio + ATA_DMA_CMD);
2965
2966	/* one-PIO-cycle guaranteed wait, per spec, for HDMA1:0 transition */
2967	ata_sff_dma_pause(ap);
2968}
2969EXPORT_SYMBOL_GPL(ata_bmdma_stop);
2970
2971/**
2972 *	ata_bmdma_status - Read PCI IDE BMDMA status
2973 *	@ap: Port associated with this ATA transaction.
2974 *
2975 *	Read and return BMDMA status register.
2976 *
2977 *	May be used as the bmdma_status() entry in ata_port_operations.
2978 *
2979 *	LOCKING:
2980 *	spin_lock_irqsave(host lock)
2981 */
2982u8 ata_bmdma_status(struct ata_port *ap)
2983{
2984	return ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);
2985}
2986EXPORT_SYMBOL_GPL(ata_bmdma_status);
2987
2988
2989/**
2990 *	ata_bmdma_port_start - Set port up for bmdma.
2991 *	@ap: Port to initialize
2992 *
2993 *	Called just after data structures for each port are
2994 *	initialized.  Allocates space for PRD table.
2995 *
2996 *	May be used as the port_start() entry in ata_port_operations.
2997 *
2998 *	LOCKING:
2999 *	Inherited from caller.
3000 */
3001int ata_bmdma_port_start(struct ata_port *ap)
3002{
3003	if (ap->mwdma_mask || ap->udma_mask) {
3004		ap->bmdma_prd =
3005			dmam_alloc_coherent(ap->host->dev, ATA_PRD_TBL_SZ,
3006					    &ap->bmdma_prd_dma, GFP_KERNEL);
3007		if (!ap->bmdma_prd)
3008			return -ENOMEM;
3009	}
3010
3011	return 0;
3012}
3013EXPORT_SYMBOL_GPL(ata_bmdma_port_start);
3014
3015/**
3016 *	ata_bmdma_port_start32 - Set port up for dma.
3017 *	@ap: Port to initialize
3018 *
3019 *	Called just after data structures for each port are
3020 *	initialized.  Enables 32bit PIO and allocates space for PRD
3021 *	table.
3022 *
3023 *	May be used as the port_start() entry in ata_port_operations for
3024 *	devices that are capable of 32bit PIO.
3025 *
3026 *	LOCKING:
3027 *	Inherited from caller.
3028 */
3029int ata_bmdma_port_start32(struct ata_port *ap)
3030{
3031	ap->pflags |= ATA_PFLAG_PIO32 | ATA_PFLAG_PIO32CHANGE;
3032	return ata_bmdma_port_start(ap);
3033}
3034EXPORT_SYMBOL_GPL(ata_bmdma_port_start32);
3035
3036#ifdef CONFIG_PCI
3037
3038/**
3039 *	ata_pci_bmdma_clear_simplex -	attempt to kick device out of simplex
3040 *	@pdev: PCI device
3041 *
3042 *	Some PCI ATA devices report simplex mode but in fact can be told to
3043 *	enter non simplex mode. This implements the necessary logic to
3044 *	perform the task on such devices. Calling it on other devices will
3045 *	have -undefined- behaviour.
3046 */
3047int ata_pci_bmdma_clear_simplex(struct pci_dev *pdev)
3048{
 
3049	unsigned long bmdma = pci_resource_start(pdev, 4);
3050	u8 simplex;
3051
3052	if (bmdma == 0)
3053		return -ENOENT;
3054
3055	simplex = inb(bmdma + 0x02);
3056	outb(simplex & 0x60, bmdma + 0x02);
3057	simplex = inb(bmdma + 0x02);
3058	if (simplex & 0x80)
3059		return -EOPNOTSUPP;
3060	return 0;
 
 
 
3061}
3062EXPORT_SYMBOL_GPL(ata_pci_bmdma_clear_simplex);
3063
3064static void ata_bmdma_nodma(struct ata_host *host, const char *reason)
3065{
3066	int i;
3067
3068	dev_err(host->dev, "BMDMA: %s, falling back to PIO\n", reason);
3069
3070	for (i = 0; i < 2; i++) {
3071		host->ports[i]->mwdma_mask = 0;
3072		host->ports[i]->udma_mask = 0;
3073	}
3074}
3075
3076/**
3077 *	ata_pci_bmdma_init - acquire PCI BMDMA resources and init ATA host
3078 *	@host: target ATA host
3079 *
3080 *	Acquire PCI BMDMA resources and initialize @host accordingly.
3081 *
3082 *	LOCKING:
3083 *	Inherited from calling layer (may sleep).
3084 */
3085void ata_pci_bmdma_init(struct ata_host *host)
3086{
3087	struct device *gdev = host->dev;
3088	struct pci_dev *pdev = to_pci_dev(gdev);
3089	int i, rc;
3090
3091	/* No BAR4 allocation: No DMA */
3092	if (pci_resource_start(pdev, 4) == 0) {
3093		ata_bmdma_nodma(host, "BAR4 is zero");
3094		return;
3095	}
3096
3097	/*
3098	 * Some controllers require BMDMA region to be initialized
3099	 * even if DMA is not in use to clear IRQ status via
3100	 * ->sff_irq_clear method.  Try to initialize bmdma_addr
3101	 * regardless of dma masks.
3102	 */
3103	rc = dma_set_mask_and_coherent(&pdev->dev, ATA_DMA_MASK);
3104	if (rc)
3105		ata_bmdma_nodma(host, "failed to set dma mask");
3106
3107	/* request and iomap DMA region */
3108	rc = pcim_iomap_regions(pdev, 1 << 4, dev_driver_string(gdev));
3109	if (rc) {
3110		ata_bmdma_nodma(host, "failed to request/iomap BAR4");
3111		return;
3112	}
3113	host->iomap = pcim_iomap_table(pdev);
3114
3115	for (i = 0; i < 2; i++) {
3116		struct ata_port *ap = host->ports[i];
3117		void __iomem *bmdma = host->iomap[4] + 8 * i;
3118
3119		if (ata_port_is_dummy(ap))
3120			continue;
3121
3122		ap->ioaddr.bmdma_addr = bmdma;
3123		if ((!(ap->flags & ATA_FLAG_IGN_SIMPLEX)) &&
3124		    (ioread8(bmdma + 2) & 0x80))
3125			host->flags |= ATA_HOST_SIMPLEX;
3126
3127		ata_port_desc(ap, "bmdma 0x%llx",
3128		    (unsigned long long)pci_resource_start(pdev, 4) + 8 * i);
3129	}
3130}
3131EXPORT_SYMBOL_GPL(ata_pci_bmdma_init);
3132
3133/**
3134 *	ata_pci_bmdma_prepare_host - helper to prepare PCI BMDMA ATA host
3135 *	@pdev: target PCI device
3136 *	@ppi: array of port_info, must be enough for two ports
3137 *	@r_host: out argument for the initialized ATA host
3138 *
3139 *	Helper to allocate BMDMA ATA host for @pdev, acquire all PCI
3140 *	resources and initialize it accordingly in one go.
3141 *
3142 *	LOCKING:
3143 *	Inherited from calling layer (may sleep).
3144 *
3145 *	RETURNS:
3146 *	0 on success, -errno otherwise.
3147 */
3148int ata_pci_bmdma_prepare_host(struct pci_dev *pdev,
3149			       const struct ata_port_info * const * ppi,
3150			       struct ata_host **r_host)
3151{
3152	int rc;
3153
3154	rc = ata_pci_sff_prepare_host(pdev, ppi, r_host);
3155	if (rc)
3156		return rc;
3157
3158	ata_pci_bmdma_init(*r_host);
3159	return 0;
3160}
3161EXPORT_SYMBOL_GPL(ata_pci_bmdma_prepare_host);
3162
3163/**
3164 *	ata_pci_bmdma_init_one - Initialize/register BMDMA PCI IDE controller
3165 *	@pdev: Controller to be initialized
3166 *	@ppi: array of port_info, must be enough for two ports
3167 *	@sht: scsi_host_template to use when registering the host
3168 *	@host_priv: host private_data
3169 *	@hflags: host flags
3170 *
3171 *	This function is similar to ata_pci_sff_init_one() but also
3172 *	takes care of BMDMA initialization.
3173 *
3174 *	LOCKING:
3175 *	Inherited from PCI layer (may sleep).
3176 *
3177 *	RETURNS:
3178 *	Zero on success, negative on errno-based value on error.
3179 */
3180int ata_pci_bmdma_init_one(struct pci_dev *pdev,
3181			   const struct ata_port_info * const * ppi,
3182			   struct scsi_host_template *sht, void *host_priv,
3183			   int hflags)
3184{
3185	return ata_pci_init_one(pdev, ppi, sht, host_priv, hflags, 1);
3186}
3187EXPORT_SYMBOL_GPL(ata_pci_bmdma_init_one);
3188
3189#endif /* CONFIG_PCI */
3190#endif /* CONFIG_ATA_BMDMA */
3191
3192/**
3193 *	ata_sff_port_init - Initialize SFF/BMDMA ATA port
3194 *	@ap: Port to initialize
3195 *
3196 *	Called on port allocation to initialize SFF/BMDMA specific
3197 *	fields.
3198 *
3199 *	LOCKING:
3200 *	None.
3201 */
3202void ata_sff_port_init(struct ata_port *ap)
3203{
3204	INIT_DELAYED_WORK(&ap->sff_pio_task, ata_sff_pio_task);
3205	ap->ctl = ATA_DEVCTL_OBS;
3206	ap->last_ctl = 0xFF;
3207}
3208
3209int __init ata_sff_init(void)
3210{
3211	ata_sff_wq = alloc_workqueue("ata_sff", WQ_MEM_RECLAIM, WQ_MAX_ACTIVE);
3212	if (!ata_sff_wq)
3213		return -ENOMEM;
3214
3215	return 0;
3216}
3217
3218void ata_sff_exit(void)
3219{
3220	destroy_workqueue(ata_sff_wq);
3221}