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v3.1
   1/*
   2 * PowerMac G5 SMU driver
   3 *
   4 * Copyright 2004 J. Mayer <l_indien@magic.fr>
   5 * Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
   6 *
   7 * Released under the term of the GNU GPL v2.
   8 */
   9
  10/*
  11 * TODO:
  12 *  - maybe add timeout to commands ?
  13 *  - blocking version of time functions
  14 *  - polling version of i2c commands (including timer that works with
  15 *    interrupts off)
  16 *  - maybe avoid some data copies with i2c by directly using the smu cmd
  17 *    buffer and a lower level internal interface
  18 *  - understand SMU -> CPU events and implement reception of them via
  19 *    the userland interface
  20 */
  21
  22#include <linux/types.h>
  23#include <linux/kernel.h>
  24#include <linux/device.h>
  25#include <linux/dmapool.h>
  26#include <linux/bootmem.h>
  27#include <linux/vmalloc.h>
  28#include <linux/highmem.h>
  29#include <linux/jiffies.h>
  30#include <linux/interrupt.h>
  31#include <linux/rtc.h>
  32#include <linux/completion.h>
  33#include <linux/miscdevice.h>
  34#include <linux/delay.h>
  35#include <linux/sysdev.h>
  36#include <linux/poll.h>
  37#include <linux/mutex.h>
  38#include <linux/of_device.h>
 
  39#include <linux/of_platform.h>
  40#include <linux/slab.h>
 
  41
  42#include <asm/byteorder.h>
  43#include <asm/io.h>
  44#include <asm/prom.h>
  45#include <asm/machdep.h>
  46#include <asm/pmac_feature.h>
  47#include <asm/smu.h>
  48#include <asm/sections.h>
  49#include <asm/abs_addr.h>
  50#include <asm/uaccess.h>
  51
  52#define VERSION "0.7"
  53#define AUTHOR  "(c) 2005 Benjamin Herrenschmidt, IBM Corp."
  54
  55#undef DEBUG_SMU
  56
  57#ifdef DEBUG_SMU
  58#define DPRINTK(fmt, args...) do { printk(KERN_DEBUG fmt , ##args); } while (0)
  59#else
  60#define DPRINTK(fmt, args...) do { } while (0)
  61#endif
  62
  63/*
  64 * This is the command buffer passed to the SMU hardware
  65 */
  66#define SMU_MAX_DATA	254
  67
  68struct smu_cmd_buf {
  69	u8 cmd;
  70	u8 length;
  71	u8 data[SMU_MAX_DATA];
  72};
  73
  74struct smu_device {
  75	spinlock_t		lock;
  76	struct device_node	*of_node;
  77	struct platform_device	*of_dev;
  78	int			doorbell;	/* doorbell gpio */
  79	u32 __iomem		*db_buf;	/* doorbell buffer */
  80	struct device_node	*db_node;
  81	unsigned int		db_irq;
  82	int			msg;
  83	struct device_node	*msg_node;
  84	unsigned int		msg_irq;
  85	struct smu_cmd_buf	*cmd_buf;	/* command buffer virtual */
  86	u32			cmd_buf_abs;	/* command buffer absolute */
  87	struct list_head	cmd_list;
  88	struct smu_cmd		*cmd_cur;	/* pending command */
  89	int			broken_nap;
  90	struct list_head	cmd_i2c_list;
  91	struct smu_i2c_cmd	*cmd_i2c_cur;	/* pending i2c command */
  92	struct timer_list	i2c_timer;
  93};
  94
  95/*
  96 * I don't think there will ever be more than one SMU, so
  97 * for now, just hard code that
  98 */
  99static DEFINE_MUTEX(smu_mutex);
 100static struct smu_device	*smu;
 101static DEFINE_MUTEX(smu_part_access);
 102static int smu_irq_inited;
 
 103
 104static void smu_i2c_retry(unsigned long data);
 105
 106/*
 107 * SMU driver low level stuff
 108 */
 109
 110static void smu_start_cmd(void)
 111{
 112	unsigned long faddr, fend;
 113	struct smu_cmd *cmd;
 114
 115	if (list_empty(&smu->cmd_list))
 116		return;
 117
 118	/* Fetch first command in queue */
 119	cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link);
 120	smu->cmd_cur = cmd;
 121	list_del(&cmd->link);
 122
 123	DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd,
 124		cmd->data_len);
 125	DPRINTK("SMU: data buffer: %02x %02x %02x %02x %02x %02x %02x %02x\n",
 126		((u8 *)cmd->data_buf)[0], ((u8 *)cmd->data_buf)[1],
 127		((u8 *)cmd->data_buf)[2], ((u8 *)cmd->data_buf)[3],
 128		((u8 *)cmd->data_buf)[4], ((u8 *)cmd->data_buf)[5],
 129		((u8 *)cmd->data_buf)[6], ((u8 *)cmd->data_buf)[7]);
 130
 131	/* Fill the SMU command buffer */
 132	smu->cmd_buf->cmd = cmd->cmd;
 133	smu->cmd_buf->length = cmd->data_len;
 134	memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len);
 135
 136	/* Flush command and data to RAM */
 137	faddr = (unsigned long)smu->cmd_buf;
 138	fend = faddr + smu->cmd_buf->length + 2;
 139	flush_inval_dcache_range(faddr, fend);
 140
 141
 142	/* We also disable NAP mode for the duration of the command
 143	 * on U3 based machines.
 144	 * This is slightly racy as it can be written back to 1 by a sysctl
 145	 * but that never happens in practice. There seem to be an issue with
 146	 * U3 based machines such as the iMac G5 where napping for the
 147	 * whole duration of the command prevents the SMU from fetching it
 148	 * from memory. This might be related to the strange i2c based
 149	 * mechanism the SMU uses to access memory.
 150	 */
 151	if (smu->broken_nap)
 152		powersave_nap = 0;
 153
 154	/* This isn't exactly a DMA mapping here, I suspect
 155	 * the SMU is actually communicating with us via i2c to the
 156	 * northbridge or the CPU to access RAM.
 157	 */
 158	writel(smu->cmd_buf_abs, smu->db_buf);
 159
 160	/* Ring the SMU doorbell */
 161	pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4);
 162}
 163
 164
 165static irqreturn_t smu_db_intr(int irq, void *arg)
 166{
 167	unsigned long flags;
 168	struct smu_cmd *cmd;
 169	void (*done)(struct smu_cmd *cmd, void *misc) = NULL;
 170	void *misc = NULL;
 171	u8 gpio;
 172	int rc = 0;
 173
 174	/* SMU completed the command, well, we hope, let's make sure
 175	 * of it
 176	 */
 177	spin_lock_irqsave(&smu->lock, flags);
 178
 179	gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
 180	if ((gpio & 7) != 7) {
 181		spin_unlock_irqrestore(&smu->lock, flags);
 182		return IRQ_HANDLED;
 183	}
 184
 185	cmd = smu->cmd_cur;
 186	smu->cmd_cur = NULL;
 187	if (cmd == NULL)
 188		goto bail;
 189
 190	if (rc == 0) {
 191		unsigned long faddr;
 192		int reply_len;
 193		u8 ack;
 194
 195		/* CPU might have brought back the cache line, so we need
 196		 * to flush again before peeking at the SMU response. We
 197		 * flush the entire buffer for now as we haven't read the
 198		 * reply length (it's only 2 cache lines anyway)
 199		 */
 200		faddr = (unsigned long)smu->cmd_buf;
 201		flush_inval_dcache_range(faddr, faddr + 256);
 202
 203		/* Now check ack */
 204		ack = (~cmd->cmd) & 0xff;
 205		if (ack != smu->cmd_buf->cmd) {
 206			DPRINTK("SMU: incorrect ack, want %x got %x\n",
 207				ack, smu->cmd_buf->cmd);
 208			rc = -EIO;
 209		}
 210		reply_len = rc == 0 ? smu->cmd_buf->length : 0;
 211		DPRINTK("SMU: reply len: %d\n", reply_len);
 212		if (reply_len > cmd->reply_len) {
 213			printk(KERN_WARNING "SMU: reply buffer too small,"
 214			       "got %d bytes for a %d bytes buffer\n",
 215			       reply_len, cmd->reply_len);
 216			reply_len = cmd->reply_len;
 217		}
 218		cmd->reply_len = reply_len;
 219		if (cmd->reply_buf && reply_len)
 220			memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len);
 221	}
 222
 223	/* Now complete the command. Write status last in order as we lost
 224	 * ownership of the command structure as soon as it's no longer -1
 225	 */
 226	done = cmd->done;
 227	misc = cmd->misc;
 228	mb();
 229	cmd->status = rc;
 230
 231	/* Re-enable NAP mode */
 232	if (smu->broken_nap)
 233		powersave_nap = 1;
 234 bail:
 235	/* Start next command if any */
 236	smu_start_cmd();
 237	spin_unlock_irqrestore(&smu->lock, flags);
 238
 239	/* Call command completion handler if any */
 240	if (done)
 241		done(cmd, misc);
 242
 243	/* It's an edge interrupt, nothing to do */
 244	return IRQ_HANDLED;
 245}
 246
 247
 248static irqreturn_t smu_msg_intr(int irq, void *arg)
 249{
 250	/* I don't quite know what to do with this one, we seem to never
 251	 * receive it, so I suspect we have to arm it someway in the SMU
 252	 * to start getting events that way.
 253	 */
 254
 255	printk(KERN_INFO "SMU: message interrupt !\n");
 256
 257	/* It's an edge interrupt, nothing to do */
 258	return IRQ_HANDLED;
 259}
 260
 261
 262/*
 263 * Queued command management.
 264 *
 265 */
 266
 267int smu_queue_cmd(struct smu_cmd *cmd)
 268{
 269	unsigned long flags;
 270
 271	if (smu == NULL)
 272		return -ENODEV;
 273	if (cmd->data_len > SMU_MAX_DATA ||
 274	    cmd->reply_len > SMU_MAX_DATA)
 275		return -EINVAL;
 276
 277	cmd->status = 1;
 278	spin_lock_irqsave(&smu->lock, flags);
 279	list_add_tail(&cmd->link, &smu->cmd_list);
 280	if (smu->cmd_cur == NULL)
 281		smu_start_cmd();
 282	spin_unlock_irqrestore(&smu->lock, flags);
 283
 284	/* Workaround for early calls when irq isn't available */
 285	if (!smu_irq_inited || smu->db_irq == NO_IRQ)
 286		smu_spinwait_cmd(cmd);
 287
 288	return 0;
 289}
 290EXPORT_SYMBOL(smu_queue_cmd);
 291
 292
 293int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command,
 294		     unsigned int data_len,
 295		     void (*done)(struct smu_cmd *cmd, void *misc),
 296		     void *misc, ...)
 297{
 298	struct smu_cmd *cmd = &scmd->cmd;
 299	va_list list;
 300	int i;
 301
 302	if (data_len > sizeof(scmd->buffer))
 303		return -EINVAL;
 304
 305	memset(scmd, 0, sizeof(*scmd));
 306	cmd->cmd = command;
 307	cmd->data_len = data_len;
 308	cmd->data_buf = scmd->buffer;
 309	cmd->reply_len = sizeof(scmd->buffer);
 310	cmd->reply_buf = scmd->buffer;
 311	cmd->done = done;
 312	cmd->misc = misc;
 313
 314	va_start(list, misc);
 315	for (i = 0; i < data_len; ++i)
 316		scmd->buffer[i] = (u8)va_arg(list, int);
 317	va_end(list);
 318
 319	return smu_queue_cmd(cmd);
 320}
 321EXPORT_SYMBOL(smu_queue_simple);
 322
 323
 324void smu_poll(void)
 325{
 326	u8 gpio;
 327
 328	if (smu == NULL)
 329		return;
 330
 331	gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
 332	if ((gpio & 7) == 7)
 333		smu_db_intr(smu->db_irq, smu);
 334}
 335EXPORT_SYMBOL(smu_poll);
 336
 337
 338void smu_done_complete(struct smu_cmd *cmd, void *misc)
 339{
 340	struct completion *comp = misc;
 341
 342	complete(comp);
 343}
 344EXPORT_SYMBOL(smu_done_complete);
 345
 346
 347void smu_spinwait_cmd(struct smu_cmd *cmd)
 348{
 349	while(cmd->status == 1)
 350		smu_poll();
 351}
 352EXPORT_SYMBOL(smu_spinwait_cmd);
 353
 354
 355/* RTC low level commands */
 356static inline int bcd2hex (int n)
 357{
 358	return (((n & 0xf0) >> 4) * 10) + (n & 0xf);
 359}
 360
 361
 362static inline int hex2bcd (int n)
 363{
 364	return ((n / 10) << 4) + (n % 10);
 365}
 366
 367
 368static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf,
 369					struct rtc_time *time)
 370{
 371	cmd_buf->cmd = 0x8e;
 372	cmd_buf->length = 8;
 373	cmd_buf->data[0] = 0x80;
 374	cmd_buf->data[1] = hex2bcd(time->tm_sec);
 375	cmd_buf->data[2] = hex2bcd(time->tm_min);
 376	cmd_buf->data[3] = hex2bcd(time->tm_hour);
 377	cmd_buf->data[4] = time->tm_wday;
 378	cmd_buf->data[5] = hex2bcd(time->tm_mday);
 379	cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1;
 380	cmd_buf->data[7] = hex2bcd(time->tm_year - 100);
 381}
 382
 383
 384int smu_get_rtc_time(struct rtc_time *time, int spinwait)
 385{
 386	struct smu_simple_cmd cmd;
 387	int rc;
 388
 389	if (smu == NULL)
 390		return -ENODEV;
 391
 392	memset(time, 0, sizeof(struct rtc_time));
 393	rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL,
 394			      SMU_CMD_RTC_GET_DATETIME);
 395	if (rc)
 396		return rc;
 397	smu_spinwait_simple(&cmd);
 398
 399	time->tm_sec = bcd2hex(cmd.buffer[0]);
 400	time->tm_min = bcd2hex(cmd.buffer[1]);
 401	time->tm_hour = bcd2hex(cmd.buffer[2]);
 402	time->tm_wday = bcd2hex(cmd.buffer[3]);
 403	time->tm_mday = bcd2hex(cmd.buffer[4]);
 404	time->tm_mon = bcd2hex(cmd.buffer[5]) - 1;
 405	time->tm_year = bcd2hex(cmd.buffer[6]) + 100;
 406
 407	return 0;
 408}
 409
 410
 411int smu_set_rtc_time(struct rtc_time *time, int spinwait)
 412{
 413	struct smu_simple_cmd cmd;
 414	int rc;
 415
 416	if (smu == NULL)
 417		return -ENODEV;
 418
 419	rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL,
 420			      SMU_CMD_RTC_SET_DATETIME,
 421			      hex2bcd(time->tm_sec),
 422			      hex2bcd(time->tm_min),
 423			      hex2bcd(time->tm_hour),
 424			      time->tm_wday,
 425			      hex2bcd(time->tm_mday),
 426			      hex2bcd(time->tm_mon) + 1,
 427			      hex2bcd(time->tm_year - 100));
 428	if (rc)
 429		return rc;
 430	smu_spinwait_simple(&cmd);
 431
 432	return 0;
 433}
 434
 435
 436void smu_shutdown(void)
 437{
 438	struct smu_simple_cmd cmd;
 439
 440	if (smu == NULL)
 441		return;
 442
 443	if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL,
 444			     'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0))
 445		return;
 446	smu_spinwait_simple(&cmd);
 447	for (;;)
 448		;
 449}
 450
 451
 452void smu_restart(void)
 453{
 454	struct smu_simple_cmd cmd;
 455
 456	if (smu == NULL)
 457		return;
 458
 459	if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL,
 460			     'R', 'E', 'S', 'T', 'A', 'R', 'T', 0))
 461		return;
 462	smu_spinwait_simple(&cmd);
 463	for (;;)
 464		;
 465}
 466
 467
 468int smu_present(void)
 469{
 470	return smu != NULL;
 471}
 472EXPORT_SYMBOL(smu_present);
 473
 474
 475int __init smu_init (void)
 476{
 477	struct device_node *np;
 478	const u32 *data;
 479	int ret = 0;
 480
 481        np = of_find_node_by_type(NULL, "smu");
 482        if (np == NULL)
 483		return -ENODEV;
 484
 485	printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR);
 486
 
 
 
 
 
 487	if (smu_cmdbuf_abs == 0) {
 488		printk(KERN_ERR "SMU: Command buffer not allocated !\n");
 489		ret = -EINVAL;
 490		goto fail_np;
 491	}
 492
 493	smu = alloc_bootmem(sizeof(struct smu_device));
 494
 495	spin_lock_init(&smu->lock);
 496	INIT_LIST_HEAD(&smu->cmd_list);
 497	INIT_LIST_HEAD(&smu->cmd_i2c_list);
 498	smu->of_node = np;
 499	smu->db_irq = NO_IRQ;
 500	smu->msg_irq = NO_IRQ;
 501
 502	/* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a
 503	 * 32 bits value safely
 504	 */
 505	smu->cmd_buf_abs = (u32)smu_cmdbuf_abs;
 506	smu->cmd_buf = (struct smu_cmd_buf *)abs_to_virt(smu_cmdbuf_abs);
 507
 508	smu->db_node = of_find_node_by_name(NULL, "smu-doorbell");
 509	if (smu->db_node == NULL) {
 510		printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n");
 511		ret = -ENXIO;
 512		goto fail_bootmem;
 513	}
 514	data = of_get_property(smu->db_node, "reg", NULL);
 515	if (data == NULL) {
 516		printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n");
 517		ret = -ENXIO;
 518		goto fail_db_node;
 519	}
 520
 521	/* Current setup has one doorbell GPIO that does both doorbell
 522	 * and ack. GPIOs are at 0x50, best would be to find that out
 523	 * in the device-tree though.
 524	 */
 525	smu->doorbell = *data;
 526	if (smu->doorbell < 0x50)
 527		smu->doorbell += 0x50;
 528
 529	/* Now look for the smu-interrupt GPIO */
 530	do {
 531		smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt");
 532		if (smu->msg_node == NULL)
 533			break;
 534		data = of_get_property(smu->msg_node, "reg", NULL);
 535		if (data == NULL) {
 536			of_node_put(smu->msg_node);
 537			smu->msg_node = NULL;
 538			break;
 539		}
 540		smu->msg = *data;
 541		if (smu->msg < 0x50)
 542			smu->msg += 0x50;
 543	} while(0);
 544
 545	/* Doorbell buffer is currently hard-coded, I didn't find a proper
 546	 * device-tree entry giving the address. Best would probably to use
 547	 * an offset for K2 base though, but let's do it that way for now.
 548	 */
 549	smu->db_buf = ioremap(0x8000860c, 0x1000);
 550	if (smu->db_buf == NULL) {
 551		printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n");
 552		ret = -ENXIO;
 553		goto fail_msg_node;
 554	}
 555
 556	/* U3 has an issue with NAP mode when issuing SMU commands */
 557	smu->broken_nap = pmac_get_uninorth_variant() < 4;
 558	if (smu->broken_nap)
 559		printk(KERN_INFO "SMU: using NAP mode workaround\n");
 560
 561	sys_ctrler = SYS_CTRLER_SMU;
 562	return 0;
 563
 564fail_msg_node:
 565	if (smu->msg_node)
 566		of_node_put(smu->msg_node);
 567fail_db_node:
 568	of_node_put(smu->db_node);
 569fail_bootmem:
 570	free_bootmem((unsigned long)smu, sizeof(struct smu_device));
 571	smu = NULL;
 572fail_np:
 573	of_node_put(np);
 574	return ret;
 575}
 576
 577
 578static int smu_late_init(void)
 579{
 580	if (!smu)
 581		return 0;
 582
 583	init_timer(&smu->i2c_timer);
 584	smu->i2c_timer.function = smu_i2c_retry;
 585	smu->i2c_timer.data = (unsigned long)smu;
 586
 587	if (smu->db_node) {
 588		smu->db_irq = irq_of_parse_and_map(smu->db_node, 0);
 589		if (smu->db_irq == NO_IRQ)
 590			printk(KERN_ERR "smu: failed to map irq for node %s\n",
 591			       smu->db_node->full_name);
 592	}
 593	if (smu->msg_node) {
 594		smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0);
 595		if (smu->msg_irq == NO_IRQ)
 596			printk(KERN_ERR "smu: failed to map irq for node %s\n",
 597			       smu->msg_node->full_name);
 598	}
 599
 600	/*
 601	 * Try to request the interrupts
 602	 */
 603
 604	if (smu->db_irq != NO_IRQ) {
 605		if (request_irq(smu->db_irq, smu_db_intr,
 606				IRQF_SHARED, "SMU doorbell", smu) < 0) {
 607			printk(KERN_WARNING "SMU: can't "
 608			       "request interrupt %d\n",
 609			       smu->db_irq);
 610			smu->db_irq = NO_IRQ;
 611		}
 612	}
 613
 614	if (smu->msg_irq != NO_IRQ) {
 615		if (request_irq(smu->msg_irq, smu_msg_intr,
 616				IRQF_SHARED, "SMU message", smu) < 0) {
 617			printk(KERN_WARNING "SMU: can't "
 618			       "request interrupt %d\n",
 619			       smu->msg_irq);
 620			smu->msg_irq = NO_IRQ;
 621		}
 622	}
 623
 624	smu_irq_inited = 1;
 625	return 0;
 626}
 627/* This has to be before arch_initcall as the low i2c stuff relies on the
 628 * above having been done before we reach arch_initcalls
 629 */
 630core_initcall(smu_late_init);
 631
 632/*
 633 * sysfs visibility
 634 */
 635
 636static void smu_expose_childs(struct work_struct *unused)
 637{
 638	struct device_node *np;
 639
 640	for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;)
 641		if (of_device_is_compatible(np, "smu-sensors"))
 642			of_platform_device_create(np, "smu-sensors",
 643						  &smu->of_dev->dev);
 644}
 645
 646static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs);
 647
 648static int smu_platform_probe(struct platform_device* dev)
 649{
 650	if (!smu)
 651		return -ENODEV;
 652	smu->of_dev = dev;
 653
 654	/*
 655	 * Ok, we are matched, now expose all i2c busses. We have to defer
 656	 * that unfortunately or it would deadlock inside the device model
 657	 */
 658	schedule_work(&smu_expose_childs_work);
 659
 660	return 0;
 661}
 662
 663static const struct of_device_id smu_platform_match[] =
 664{
 665	{
 666		.type		= "smu",
 667	},
 668	{},
 669};
 670
 671static struct platform_driver smu_of_platform_driver =
 672{
 673	.driver = {
 674		.name = "smu",
 675		.owner = THIS_MODULE,
 676		.of_match_table = smu_platform_match,
 677	},
 678	.probe		= smu_platform_probe,
 679};
 680
 681static int __init smu_init_sysfs(void)
 682{
 683	/*
 684	 * Due to sysfs bogosity, a sysdev is not a real device, so
 685	 * we should in fact create both if we want sysdev semantics
 686	 * for power management.
 687	 * For now, we don't power manage machines with an SMU chip,
 688	 * I'm a bit too far from figuring out how that works with those
 689	 * new chipsets, but that will come back and bite us
 690	 */
 691	platform_driver_register(&smu_of_platform_driver);
 692	return 0;
 693}
 694
 695device_initcall(smu_init_sysfs);
 696
 697struct platform_device *smu_get_ofdev(void)
 698{
 699	if (!smu)
 700		return NULL;
 701	return smu->of_dev;
 702}
 703
 704EXPORT_SYMBOL_GPL(smu_get_ofdev);
 705
 706/*
 707 * i2c interface
 708 */
 709
 710static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail)
 711{
 712	void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done;
 713	void *misc = cmd->misc;
 714	unsigned long flags;
 715
 716	/* Check for read case */
 717	if (!fail && cmd->read) {
 718		if (cmd->pdata[0] < 1)
 719			fail = 1;
 720		else
 721			memcpy(cmd->info.data, &cmd->pdata[1],
 722			       cmd->info.datalen);
 723	}
 724
 725	DPRINTK("SMU: completing, success: %d\n", !fail);
 726
 727	/* Update status and mark no pending i2c command with lock
 728	 * held so nobody comes in while we dequeue an eventual
 729	 * pending next i2c command
 730	 */
 731	spin_lock_irqsave(&smu->lock, flags);
 732	smu->cmd_i2c_cur = NULL;
 733	wmb();
 734	cmd->status = fail ? -EIO : 0;
 735
 736	/* Is there another i2c command waiting ? */
 737	if (!list_empty(&smu->cmd_i2c_list)) {
 738		struct smu_i2c_cmd *newcmd;
 739
 740		/* Fetch it, new current, remove from list */
 741		newcmd = list_entry(smu->cmd_i2c_list.next,
 742				    struct smu_i2c_cmd, link);
 743		smu->cmd_i2c_cur = newcmd;
 744		list_del(&cmd->link);
 745
 746		/* Queue with low level smu */
 747		list_add_tail(&cmd->scmd.link, &smu->cmd_list);
 748		if (smu->cmd_cur == NULL)
 749			smu_start_cmd();
 750	}
 751	spin_unlock_irqrestore(&smu->lock, flags);
 752
 753	/* Call command completion handler if any */
 754	if (done)
 755		done(cmd, misc);
 756
 757}
 758
 759
 760static void smu_i2c_retry(unsigned long data)
 761{
 762	struct smu_i2c_cmd	*cmd = smu->cmd_i2c_cur;
 763
 764	DPRINTK("SMU: i2c failure, requeuing...\n");
 765
 766	/* requeue command simply by resetting reply_len */
 767	cmd->pdata[0] = 0xff;
 768	cmd->scmd.reply_len = sizeof(cmd->pdata);
 769	smu_queue_cmd(&cmd->scmd);
 770}
 771
 772
 773static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc)
 774{
 775	struct smu_i2c_cmd	*cmd = misc;
 776	int			fail = 0;
 777
 778	DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n",
 779		cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len);
 780
 781	/* Check for possible status */
 782	if (scmd->status < 0)
 783		fail = 1;
 784	else if (cmd->read) {
 785		if (cmd->stage == 0)
 786			fail = cmd->pdata[0] != 0;
 787		else
 788			fail = cmd->pdata[0] >= 0x80;
 789	} else {
 790		fail = cmd->pdata[0] != 0;
 791	}
 792
 793	/* Handle failures by requeuing command, after 5ms interval
 794	 */
 795	if (fail && --cmd->retries > 0) {
 796		DPRINTK("SMU: i2c failure, starting timer...\n");
 797		BUG_ON(cmd != smu->cmd_i2c_cur);
 798		if (!smu_irq_inited) {
 799			mdelay(5);
 800			smu_i2c_retry(0);
 801			return;
 802		}
 803		mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5));
 804		return;
 805	}
 806
 807	/* If failure or stage 1, command is complete */
 808	if (fail || cmd->stage != 0) {
 809		smu_i2c_complete_command(cmd, fail);
 810		return;
 811	}
 812
 813	DPRINTK("SMU: going to stage 1\n");
 814
 815	/* Ok, initial command complete, now poll status */
 816	scmd->reply_buf = cmd->pdata;
 817	scmd->reply_len = sizeof(cmd->pdata);
 818	scmd->data_buf = cmd->pdata;
 819	scmd->data_len = 1;
 820	cmd->pdata[0] = 0;
 821	cmd->stage = 1;
 822	cmd->retries = 20;
 823	smu_queue_cmd(scmd);
 824}
 825
 826
 827int smu_queue_i2c(struct smu_i2c_cmd *cmd)
 828{
 829	unsigned long flags;
 830
 831	if (smu == NULL)
 832		return -ENODEV;
 833
 834	/* Fill most fields of scmd */
 835	cmd->scmd.cmd = SMU_CMD_I2C_COMMAND;
 836	cmd->scmd.done = smu_i2c_low_completion;
 837	cmd->scmd.misc = cmd;
 838	cmd->scmd.reply_buf = cmd->pdata;
 839	cmd->scmd.reply_len = sizeof(cmd->pdata);
 840	cmd->scmd.data_buf = (u8 *)(char *)&cmd->info;
 841	cmd->scmd.status = 1;
 842	cmd->stage = 0;
 843	cmd->pdata[0] = 0xff;
 844	cmd->retries = 20;
 845	cmd->status = 1;
 846
 847	/* Check transfer type, sanitize some "info" fields
 848	 * based on transfer type and do more checking
 849	 */
 850	cmd->info.caddr = cmd->info.devaddr;
 851	cmd->read = cmd->info.devaddr & 0x01;
 852	switch(cmd->info.type) {
 853	case SMU_I2C_TRANSFER_SIMPLE:
 854		memset(&cmd->info.sublen, 0, 4);
 855		break;
 856	case SMU_I2C_TRANSFER_COMBINED:
 857		cmd->info.devaddr &= 0xfe;
 858	case SMU_I2C_TRANSFER_STDSUB:
 859		if (cmd->info.sublen > 3)
 860			return -EINVAL;
 861		break;
 862	default:
 863		return -EINVAL;
 864	}
 865
 866	/* Finish setting up command based on transfer direction
 867	 */
 868	if (cmd->read) {
 869		if (cmd->info.datalen > SMU_I2C_READ_MAX)
 870			return -EINVAL;
 871		memset(cmd->info.data, 0xff, cmd->info.datalen);
 872		cmd->scmd.data_len = 9;
 873	} else {
 874		if (cmd->info.datalen > SMU_I2C_WRITE_MAX)
 875			return -EINVAL;
 876		cmd->scmd.data_len = 9 + cmd->info.datalen;
 877	}
 878
 879	DPRINTK("SMU: i2c enqueuing command\n");
 880	DPRINTK("SMU:   %s, len=%d bus=%x addr=%x sub0=%x type=%x\n",
 881		cmd->read ? "read" : "write", cmd->info.datalen,
 882		cmd->info.bus, cmd->info.caddr,
 883		cmd->info.subaddr[0], cmd->info.type);
 884
 885
 886	/* Enqueue command in i2c list, and if empty, enqueue also in
 887	 * main command list
 888	 */
 889	spin_lock_irqsave(&smu->lock, flags);
 890	if (smu->cmd_i2c_cur == NULL) {
 891		smu->cmd_i2c_cur = cmd;
 892		list_add_tail(&cmd->scmd.link, &smu->cmd_list);
 893		if (smu->cmd_cur == NULL)
 894			smu_start_cmd();
 895	} else
 896		list_add_tail(&cmd->link, &smu->cmd_i2c_list);
 897	spin_unlock_irqrestore(&smu->lock, flags);
 898
 899	return 0;
 900}
 901
 902/*
 903 * Handling of "partitions"
 904 */
 905
 906static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len)
 907{
 908	DECLARE_COMPLETION_ONSTACK(comp);
 909	unsigned int chunk;
 910	struct smu_cmd cmd;
 911	int rc;
 912	u8 params[8];
 913
 914	/* We currently use a chunk size of 0xe. We could check the
 915	 * SMU firmware version and use bigger sizes though
 916	 */
 917	chunk = 0xe;
 918
 919	while (len) {
 920		unsigned int clen = min(len, chunk);
 921
 922		cmd.cmd = SMU_CMD_MISC_ee_COMMAND;
 923		cmd.data_len = 7;
 924		cmd.data_buf = params;
 925		cmd.reply_len = chunk;
 926		cmd.reply_buf = dest;
 927		cmd.done = smu_done_complete;
 928		cmd.misc = &comp;
 929		params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC;
 930		params[1] = 0x4;
 931		*((u32 *)&params[2]) = addr;
 932		params[6] = clen;
 933
 934		rc = smu_queue_cmd(&cmd);
 935		if (rc)
 936			return rc;
 937		wait_for_completion(&comp);
 938		if (cmd.status != 0)
 939			return rc;
 940		if (cmd.reply_len != clen) {
 941			printk(KERN_DEBUG "SMU: short read in "
 942			       "smu_read_datablock, got: %d, want: %d\n",
 943			       cmd.reply_len, clen);
 944			return -EIO;
 945		}
 946		len -= clen;
 947		addr += clen;
 948		dest += clen;
 949	}
 950	return 0;
 951}
 952
 953static struct smu_sdbp_header *smu_create_sdb_partition(int id)
 954{
 955	DECLARE_COMPLETION_ONSTACK(comp);
 956	struct smu_simple_cmd cmd;
 957	unsigned int addr, len, tlen;
 958	struct smu_sdbp_header *hdr;
 959	struct property *prop;
 960
 961	/* First query the partition info */
 962	DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq);
 963	smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2,
 964			 smu_done_complete, &comp,
 965			 SMU_CMD_PARTITION_LATEST, id);
 966	wait_for_completion(&comp);
 967	DPRINTK("SMU: done, status: %d, reply_len: %d\n",
 968		cmd.cmd.status, cmd.cmd.reply_len);
 969
 970	/* Partition doesn't exist (or other error) */
 971	if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6)
 972		return NULL;
 973
 974	/* Fetch address and length from reply */
 975	addr = *((u16 *)cmd.buffer);
 976	len = cmd.buffer[3] << 2;
 977	/* Calucluate total length to allocate, including the 17 bytes
 978	 * for "sdb-partition-XX" that we append at the end of the buffer
 979	 */
 980	tlen = sizeof(struct property) + len + 18;
 981
 982	prop = kzalloc(tlen, GFP_KERNEL);
 983	if (prop == NULL)
 984		return NULL;
 985	hdr = (struct smu_sdbp_header *)(prop + 1);
 986	prop->name = ((char *)prop) + tlen - 18;
 987	sprintf(prop->name, "sdb-partition-%02x", id);
 988	prop->length = len;
 989	prop->value = hdr;
 990	prop->next = NULL;
 991
 992	/* Read the datablock */
 993	if (smu_read_datablock((u8 *)hdr, addr, len)) {
 994		printk(KERN_DEBUG "SMU: datablock read failed while reading "
 995		       "partition %02x !\n", id);
 996		goto failure;
 997	}
 998
 999	/* Got it, check a few things and create the property */
1000	if (hdr->id != id) {
1001		printk(KERN_DEBUG "SMU: Reading partition %02x and got "
1002		       "%02x !\n", id, hdr->id);
1003		goto failure;
1004	}
1005	if (prom_add_property(smu->of_node, prop)) {
1006		printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x "
1007		       "property !\n", id);
1008		goto failure;
1009	}
1010
1011	return hdr;
1012 failure:
1013	kfree(prop);
1014	return NULL;
1015}
1016
1017/* Note: Only allowed to return error code in pointers (using ERR_PTR)
1018 * when interruptible is 1
1019 */
1020const struct smu_sdbp_header *__smu_get_sdb_partition(int id,
1021		unsigned int *size, int interruptible)
1022{
1023	char pname[32];
1024	const struct smu_sdbp_header *part;
1025
1026	if (!smu)
1027		return NULL;
1028
1029	sprintf(pname, "sdb-partition-%02x", id);
1030
1031	DPRINTK("smu_get_sdb_partition(%02x)\n", id);
1032
1033	if (interruptible) {
1034		int rc;
1035		rc = mutex_lock_interruptible(&smu_part_access);
1036		if (rc)
1037			return ERR_PTR(rc);
1038	} else
1039		mutex_lock(&smu_part_access);
1040
1041	part = of_get_property(smu->of_node, pname, size);
1042	if (part == NULL) {
1043		DPRINTK("trying to extract from SMU ...\n");
1044		part = smu_create_sdb_partition(id);
1045		if (part != NULL && size)
1046			*size = part->len << 2;
1047	}
1048	mutex_unlock(&smu_part_access);
1049	return part;
1050}
1051
1052const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size)
1053{
1054	return __smu_get_sdb_partition(id, size, 0);
1055}
1056EXPORT_SYMBOL(smu_get_sdb_partition);
1057
1058
1059/*
1060 * Userland driver interface
1061 */
1062
1063
1064static LIST_HEAD(smu_clist);
1065static DEFINE_SPINLOCK(smu_clist_lock);
1066
1067enum smu_file_mode {
1068	smu_file_commands,
1069	smu_file_events,
1070	smu_file_closing
1071};
1072
1073struct smu_private
1074{
1075	struct list_head	list;
1076	enum smu_file_mode	mode;
1077	int			busy;
1078	struct smu_cmd		cmd;
1079	spinlock_t		lock;
1080	wait_queue_head_t	wait;
1081	u8			buffer[SMU_MAX_DATA];
1082};
1083
1084
1085static int smu_open(struct inode *inode, struct file *file)
1086{
1087	struct smu_private *pp;
1088	unsigned long flags;
1089
1090	pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL);
1091	if (pp == 0)
1092		return -ENOMEM;
1093	spin_lock_init(&pp->lock);
1094	pp->mode = smu_file_commands;
1095	init_waitqueue_head(&pp->wait);
1096
1097	mutex_lock(&smu_mutex);
1098	spin_lock_irqsave(&smu_clist_lock, flags);
1099	list_add(&pp->list, &smu_clist);
1100	spin_unlock_irqrestore(&smu_clist_lock, flags);
1101	file->private_data = pp;
1102	mutex_unlock(&smu_mutex);
1103
1104	return 0;
1105}
1106
1107
1108static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc)
1109{
1110	struct smu_private *pp = misc;
1111
1112	wake_up_all(&pp->wait);
1113}
1114
1115
1116static ssize_t smu_write(struct file *file, const char __user *buf,
1117			 size_t count, loff_t *ppos)
1118{
1119	struct smu_private *pp = file->private_data;
1120	unsigned long flags;
1121	struct smu_user_cmd_hdr hdr;
1122	int rc = 0;
1123
1124	if (pp->busy)
1125		return -EBUSY;
1126	else if (copy_from_user(&hdr, buf, sizeof(hdr)))
1127		return -EFAULT;
1128	else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) {
1129		pp->mode = smu_file_events;
1130		return 0;
1131	} else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) {
1132		const struct smu_sdbp_header *part;
1133		part = __smu_get_sdb_partition(hdr.cmd, NULL, 1);
1134		if (part == NULL)
1135			return -EINVAL;
1136		else if (IS_ERR(part))
1137			return PTR_ERR(part);
1138		return 0;
1139	} else if (hdr.cmdtype != SMU_CMDTYPE_SMU)
1140		return -EINVAL;
1141	else if (pp->mode != smu_file_commands)
1142		return -EBADFD;
1143	else if (hdr.data_len > SMU_MAX_DATA)
1144		return -EINVAL;
1145
1146	spin_lock_irqsave(&pp->lock, flags);
1147	if (pp->busy) {
1148		spin_unlock_irqrestore(&pp->lock, flags);
1149		return -EBUSY;
1150	}
1151	pp->busy = 1;
1152	pp->cmd.status = 1;
1153	spin_unlock_irqrestore(&pp->lock, flags);
1154
1155	if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) {
1156		pp->busy = 0;
1157		return -EFAULT;
1158	}
1159
1160	pp->cmd.cmd = hdr.cmd;
1161	pp->cmd.data_len = hdr.data_len;
1162	pp->cmd.reply_len = SMU_MAX_DATA;
1163	pp->cmd.data_buf = pp->buffer;
1164	pp->cmd.reply_buf = pp->buffer;
1165	pp->cmd.done = smu_user_cmd_done;
1166	pp->cmd.misc = pp;
1167	rc = smu_queue_cmd(&pp->cmd);
1168	if (rc < 0)
1169		return rc;
1170	return count;
1171}
1172
1173
1174static ssize_t smu_read_command(struct file *file, struct smu_private *pp,
1175				char __user *buf, size_t count)
1176{
1177	DECLARE_WAITQUEUE(wait, current);
1178	struct smu_user_reply_hdr hdr;
1179	unsigned long flags;
1180	int size, rc = 0;
1181
1182	if (!pp->busy)
1183		return 0;
1184	if (count < sizeof(struct smu_user_reply_hdr))
1185		return -EOVERFLOW;
1186	spin_lock_irqsave(&pp->lock, flags);
1187	if (pp->cmd.status == 1) {
1188		if (file->f_flags & O_NONBLOCK) {
1189			spin_unlock_irqrestore(&pp->lock, flags);
1190			return -EAGAIN;
1191		}
1192		add_wait_queue(&pp->wait, &wait);
1193		for (;;) {
1194			set_current_state(TASK_INTERRUPTIBLE);
1195			rc = 0;
1196			if (pp->cmd.status != 1)
1197				break;
1198			rc = -ERESTARTSYS;
1199			if (signal_pending(current))
1200				break;
1201			spin_unlock_irqrestore(&pp->lock, flags);
1202			schedule();
1203			spin_lock_irqsave(&pp->lock, flags);
1204		}
1205		set_current_state(TASK_RUNNING);
1206		remove_wait_queue(&pp->wait, &wait);
1207	}
1208	spin_unlock_irqrestore(&pp->lock, flags);
1209	if (rc)
1210		return rc;
1211	if (pp->cmd.status != 0)
1212		pp->cmd.reply_len = 0;
1213	size = sizeof(hdr) + pp->cmd.reply_len;
1214	if (count < size)
1215		size = count;
1216	rc = size;
1217	hdr.status = pp->cmd.status;
1218	hdr.reply_len = pp->cmd.reply_len;
1219	if (copy_to_user(buf, &hdr, sizeof(hdr)))
1220		return -EFAULT;
1221	size -= sizeof(hdr);
1222	if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size))
1223		return -EFAULT;
1224	pp->busy = 0;
1225
1226	return rc;
1227}
1228
1229
1230static ssize_t smu_read_events(struct file *file, struct smu_private *pp,
1231			       char __user *buf, size_t count)
1232{
1233	/* Not implemented */
1234	msleep_interruptible(1000);
1235	return 0;
1236}
1237
1238
1239static ssize_t smu_read(struct file *file, char __user *buf,
1240			size_t count, loff_t *ppos)
1241{
1242	struct smu_private *pp = file->private_data;
1243
1244	if (pp->mode == smu_file_commands)
1245		return smu_read_command(file, pp, buf, count);
1246	if (pp->mode == smu_file_events)
1247		return smu_read_events(file, pp, buf, count);
1248
1249	return -EBADFD;
1250}
1251
1252static unsigned int smu_fpoll(struct file *file, poll_table *wait)
1253{
1254	struct smu_private *pp = file->private_data;
1255	unsigned int mask = 0;
1256	unsigned long flags;
1257
1258	if (pp == 0)
1259		return 0;
1260
1261	if (pp->mode == smu_file_commands) {
1262		poll_wait(file, &pp->wait, wait);
1263
1264		spin_lock_irqsave(&pp->lock, flags);
1265		if (pp->busy && pp->cmd.status != 1)
1266			mask |= POLLIN;
1267		spin_unlock_irqrestore(&pp->lock, flags);
1268	} if (pp->mode == smu_file_events) {
 
1269		/* Not yet implemented */
1270	}
1271	return mask;
1272}
1273
1274static int smu_release(struct inode *inode, struct file *file)
1275{
1276	struct smu_private *pp = file->private_data;
1277	unsigned long flags;
1278	unsigned int busy;
1279
1280	if (pp == 0)
1281		return 0;
1282
1283	file->private_data = NULL;
1284
1285	/* Mark file as closing to avoid races with new request */
1286	spin_lock_irqsave(&pp->lock, flags);
1287	pp->mode = smu_file_closing;
1288	busy = pp->busy;
1289
1290	/* Wait for any pending request to complete */
1291	if (busy && pp->cmd.status == 1) {
1292		DECLARE_WAITQUEUE(wait, current);
1293
1294		add_wait_queue(&pp->wait, &wait);
1295		for (;;) {
1296			set_current_state(TASK_UNINTERRUPTIBLE);
1297			if (pp->cmd.status != 1)
1298				break;
1299			spin_unlock_irqrestore(&pp->lock, flags);
1300			schedule();
1301			spin_lock_irqsave(&pp->lock, flags);
1302		}
1303		set_current_state(TASK_RUNNING);
1304		remove_wait_queue(&pp->wait, &wait);
1305	}
1306	spin_unlock_irqrestore(&pp->lock, flags);
1307
1308	spin_lock_irqsave(&smu_clist_lock, flags);
1309	list_del(&pp->list);
1310	spin_unlock_irqrestore(&smu_clist_lock, flags);
1311	kfree(pp);
1312
1313	return 0;
1314}
1315
1316
1317static const struct file_operations smu_device_fops = {
1318	.llseek		= no_llseek,
1319	.read		= smu_read,
1320	.write		= smu_write,
1321	.poll		= smu_fpoll,
1322	.open		= smu_open,
1323	.release	= smu_release,
1324};
1325
1326static struct miscdevice pmu_device = {
1327	MISC_DYNAMIC_MINOR, "smu", &smu_device_fops
1328};
1329
1330static int smu_device_init(void)
1331{
1332	if (!smu)
1333		return -ENODEV;
1334	if (misc_register(&pmu_device) < 0)
1335		printk(KERN_ERR "via-pmu: cannot register misc device.\n");
1336	return 0;
1337}
1338device_initcall(smu_device_init);
v4.10.11
   1/*
   2 * PowerMac G5 SMU driver
   3 *
   4 * Copyright 2004 J. Mayer <l_indien@magic.fr>
   5 * Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
   6 *
   7 * Released under the term of the GNU GPL v2.
   8 */
   9
  10/*
  11 * TODO:
  12 *  - maybe add timeout to commands ?
  13 *  - blocking version of time functions
  14 *  - polling version of i2c commands (including timer that works with
  15 *    interrupts off)
  16 *  - maybe avoid some data copies with i2c by directly using the smu cmd
  17 *    buffer and a lower level internal interface
  18 *  - understand SMU -> CPU events and implement reception of them via
  19 *    the userland interface
  20 */
  21
  22#include <linux/types.h>
  23#include <linux/kernel.h>
  24#include <linux/device.h>
  25#include <linux/dmapool.h>
  26#include <linux/bootmem.h>
  27#include <linux/vmalloc.h>
  28#include <linux/highmem.h>
  29#include <linux/jiffies.h>
  30#include <linux/interrupt.h>
  31#include <linux/rtc.h>
  32#include <linux/completion.h>
  33#include <linux/miscdevice.h>
  34#include <linux/delay.h>
 
  35#include <linux/poll.h>
  36#include <linux/mutex.h>
  37#include <linux/of_device.h>
  38#include <linux/of_irq.h>
  39#include <linux/of_platform.h>
  40#include <linux/slab.h>
  41#include <linux/memblock.h>
  42
  43#include <asm/byteorder.h>
  44#include <asm/io.h>
  45#include <asm/prom.h>
  46#include <asm/machdep.h>
  47#include <asm/pmac_feature.h>
  48#include <asm/smu.h>
  49#include <asm/sections.h>
  50#include <linux/uaccess.h>
 
  51
  52#define VERSION "0.7"
  53#define AUTHOR  "(c) 2005 Benjamin Herrenschmidt, IBM Corp."
  54
  55#undef DEBUG_SMU
  56
  57#ifdef DEBUG_SMU
  58#define DPRINTK(fmt, args...) do { printk(KERN_DEBUG fmt , ##args); } while (0)
  59#else
  60#define DPRINTK(fmt, args...) do { } while (0)
  61#endif
  62
  63/*
  64 * This is the command buffer passed to the SMU hardware
  65 */
  66#define SMU_MAX_DATA	254
  67
  68struct smu_cmd_buf {
  69	u8 cmd;
  70	u8 length;
  71	u8 data[SMU_MAX_DATA];
  72};
  73
  74struct smu_device {
  75	spinlock_t		lock;
  76	struct device_node	*of_node;
  77	struct platform_device	*of_dev;
  78	int			doorbell;	/* doorbell gpio */
  79	u32 __iomem		*db_buf;	/* doorbell buffer */
  80	struct device_node	*db_node;
  81	unsigned int		db_irq;
  82	int			msg;
  83	struct device_node	*msg_node;
  84	unsigned int		msg_irq;
  85	struct smu_cmd_buf	*cmd_buf;	/* command buffer virtual */
  86	u32			cmd_buf_abs;	/* command buffer absolute */
  87	struct list_head	cmd_list;
  88	struct smu_cmd		*cmd_cur;	/* pending command */
  89	int			broken_nap;
  90	struct list_head	cmd_i2c_list;
  91	struct smu_i2c_cmd	*cmd_i2c_cur;	/* pending i2c command */
  92	struct timer_list	i2c_timer;
  93};
  94
  95/*
  96 * I don't think there will ever be more than one SMU, so
  97 * for now, just hard code that
  98 */
  99static DEFINE_MUTEX(smu_mutex);
 100static struct smu_device	*smu;
 101static DEFINE_MUTEX(smu_part_access);
 102static int smu_irq_inited;
 103static unsigned long smu_cmdbuf_abs;
 104
 105static void smu_i2c_retry(unsigned long data);
 106
 107/*
 108 * SMU driver low level stuff
 109 */
 110
 111static void smu_start_cmd(void)
 112{
 113	unsigned long faddr, fend;
 114	struct smu_cmd *cmd;
 115
 116	if (list_empty(&smu->cmd_list))
 117		return;
 118
 119	/* Fetch first command in queue */
 120	cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link);
 121	smu->cmd_cur = cmd;
 122	list_del(&cmd->link);
 123
 124	DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd,
 125		cmd->data_len);
 126	DPRINTK("SMU: data buffer: %8ph\n", cmd->data_buf);
 
 
 
 
 127
 128	/* Fill the SMU command buffer */
 129	smu->cmd_buf->cmd = cmd->cmd;
 130	smu->cmd_buf->length = cmd->data_len;
 131	memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len);
 132
 133	/* Flush command and data to RAM */
 134	faddr = (unsigned long)smu->cmd_buf;
 135	fend = faddr + smu->cmd_buf->length + 2;
 136	flush_inval_dcache_range(faddr, fend);
 137
 138
 139	/* We also disable NAP mode for the duration of the command
 140	 * on U3 based machines.
 141	 * This is slightly racy as it can be written back to 1 by a sysctl
 142	 * but that never happens in practice. There seem to be an issue with
 143	 * U3 based machines such as the iMac G5 where napping for the
 144	 * whole duration of the command prevents the SMU from fetching it
 145	 * from memory. This might be related to the strange i2c based
 146	 * mechanism the SMU uses to access memory.
 147	 */
 148	if (smu->broken_nap)
 149		powersave_nap = 0;
 150
 151	/* This isn't exactly a DMA mapping here, I suspect
 152	 * the SMU is actually communicating with us via i2c to the
 153	 * northbridge or the CPU to access RAM.
 154	 */
 155	writel(smu->cmd_buf_abs, smu->db_buf);
 156
 157	/* Ring the SMU doorbell */
 158	pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4);
 159}
 160
 161
 162static irqreturn_t smu_db_intr(int irq, void *arg)
 163{
 164	unsigned long flags;
 165	struct smu_cmd *cmd;
 166	void (*done)(struct smu_cmd *cmd, void *misc) = NULL;
 167	void *misc = NULL;
 168	u8 gpio;
 169	int rc = 0;
 170
 171	/* SMU completed the command, well, we hope, let's make sure
 172	 * of it
 173	 */
 174	spin_lock_irqsave(&smu->lock, flags);
 175
 176	gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
 177	if ((gpio & 7) != 7) {
 178		spin_unlock_irqrestore(&smu->lock, flags);
 179		return IRQ_HANDLED;
 180	}
 181
 182	cmd = smu->cmd_cur;
 183	smu->cmd_cur = NULL;
 184	if (cmd == NULL)
 185		goto bail;
 186
 187	if (rc == 0) {
 188		unsigned long faddr;
 189		int reply_len;
 190		u8 ack;
 191
 192		/* CPU might have brought back the cache line, so we need
 193		 * to flush again before peeking at the SMU response. We
 194		 * flush the entire buffer for now as we haven't read the
 195		 * reply length (it's only 2 cache lines anyway)
 196		 */
 197		faddr = (unsigned long)smu->cmd_buf;
 198		flush_inval_dcache_range(faddr, faddr + 256);
 199
 200		/* Now check ack */
 201		ack = (~cmd->cmd) & 0xff;
 202		if (ack != smu->cmd_buf->cmd) {
 203			DPRINTK("SMU: incorrect ack, want %x got %x\n",
 204				ack, smu->cmd_buf->cmd);
 205			rc = -EIO;
 206		}
 207		reply_len = rc == 0 ? smu->cmd_buf->length : 0;
 208		DPRINTK("SMU: reply len: %d\n", reply_len);
 209		if (reply_len > cmd->reply_len) {
 210			printk(KERN_WARNING "SMU: reply buffer too small,"
 211			       "got %d bytes for a %d bytes buffer\n",
 212			       reply_len, cmd->reply_len);
 213			reply_len = cmd->reply_len;
 214		}
 215		cmd->reply_len = reply_len;
 216		if (cmd->reply_buf && reply_len)
 217			memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len);
 218	}
 219
 220	/* Now complete the command. Write status last in order as we lost
 221	 * ownership of the command structure as soon as it's no longer -1
 222	 */
 223	done = cmd->done;
 224	misc = cmd->misc;
 225	mb();
 226	cmd->status = rc;
 227
 228	/* Re-enable NAP mode */
 229	if (smu->broken_nap)
 230		powersave_nap = 1;
 231 bail:
 232	/* Start next command if any */
 233	smu_start_cmd();
 234	spin_unlock_irqrestore(&smu->lock, flags);
 235
 236	/* Call command completion handler if any */
 237	if (done)
 238		done(cmd, misc);
 239
 240	/* It's an edge interrupt, nothing to do */
 241	return IRQ_HANDLED;
 242}
 243
 244
 245static irqreturn_t smu_msg_intr(int irq, void *arg)
 246{
 247	/* I don't quite know what to do with this one, we seem to never
 248	 * receive it, so I suspect we have to arm it someway in the SMU
 249	 * to start getting events that way.
 250	 */
 251
 252	printk(KERN_INFO "SMU: message interrupt !\n");
 253
 254	/* It's an edge interrupt, nothing to do */
 255	return IRQ_HANDLED;
 256}
 257
 258
 259/*
 260 * Queued command management.
 261 *
 262 */
 263
 264int smu_queue_cmd(struct smu_cmd *cmd)
 265{
 266	unsigned long flags;
 267
 268	if (smu == NULL)
 269		return -ENODEV;
 270	if (cmd->data_len > SMU_MAX_DATA ||
 271	    cmd->reply_len > SMU_MAX_DATA)
 272		return -EINVAL;
 273
 274	cmd->status = 1;
 275	spin_lock_irqsave(&smu->lock, flags);
 276	list_add_tail(&cmd->link, &smu->cmd_list);
 277	if (smu->cmd_cur == NULL)
 278		smu_start_cmd();
 279	spin_unlock_irqrestore(&smu->lock, flags);
 280
 281	/* Workaround for early calls when irq isn't available */
 282	if (!smu_irq_inited || !smu->db_irq)
 283		smu_spinwait_cmd(cmd);
 284
 285	return 0;
 286}
 287EXPORT_SYMBOL(smu_queue_cmd);
 288
 289
 290int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command,
 291		     unsigned int data_len,
 292		     void (*done)(struct smu_cmd *cmd, void *misc),
 293		     void *misc, ...)
 294{
 295	struct smu_cmd *cmd = &scmd->cmd;
 296	va_list list;
 297	int i;
 298
 299	if (data_len > sizeof(scmd->buffer))
 300		return -EINVAL;
 301
 302	memset(scmd, 0, sizeof(*scmd));
 303	cmd->cmd = command;
 304	cmd->data_len = data_len;
 305	cmd->data_buf = scmd->buffer;
 306	cmd->reply_len = sizeof(scmd->buffer);
 307	cmd->reply_buf = scmd->buffer;
 308	cmd->done = done;
 309	cmd->misc = misc;
 310
 311	va_start(list, misc);
 312	for (i = 0; i < data_len; ++i)
 313		scmd->buffer[i] = (u8)va_arg(list, int);
 314	va_end(list);
 315
 316	return smu_queue_cmd(cmd);
 317}
 318EXPORT_SYMBOL(smu_queue_simple);
 319
 320
 321void smu_poll(void)
 322{
 323	u8 gpio;
 324
 325	if (smu == NULL)
 326		return;
 327
 328	gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
 329	if ((gpio & 7) == 7)
 330		smu_db_intr(smu->db_irq, smu);
 331}
 332EXPORT_SYMBOL(smu_poll);
 333
 334
 335void smu_done_complete(struct smu_cmd *cmd, void *misc)
 336{
 337	struct completion *comp = misc;
 338
 339	complete(comp);
 340}
 341EXPORT_SYMBOL(smu_done_complete);
 342
 343
 344void smu_spinwait_cmd(struct smu_cmd *cmd)
 345{
 346	while(cmd->status == 1)
 347		smu_poll();
 348}
 349EXPORT_SYMBOL(smu_spinwait_cmd);
 350
 351
 352/* RTC low level commands */
 353static inline int bcd2hex (int n)
 354{
 355	return (((n & 0xf0) >> 4) * 10) + (n & 0xf);
 356}
 357
 358
 359static inline int hex2bcd (int n)
 360{
 361	return ((n / 10) << 4) + (n % 10);
 362}
 363
 364
 365static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf,
 366					struct rtc_time *time)
 367{
 368	cmd_buf->cmd = 0x8e;
 369	cmd_buf->length = 8;
 370	cmd_buf->data[0] = 0x80;
 371	cmd_buf->data[1] = hex2bcd(time->tm_sec);
 372	cmd_buf->data[2] = hex2bcd(time->tm_min);
 373	cmd_buf->data[3] = hex2bcd(time->tm_hour);
 374	cmd_buf->data[4] = time->tm_wday;
 375	cmd_buf->data[5] = hex2bcd(time->tm_mday);
 376	cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1;
 377	cmd_buf->data[7] = hex2bcd(time->tm_year - 100);
 378}
 379
 380
 381int smu_get_rtc_time(struct rtc_time *time, int spinwait)
 382{
 383	struct smu_simple_cmd cmd;
 384	int rc;
 385
 386	if (smu == NULL)
 387		return -ENODEV;
 388
 389	memset(time, 0, sizeof(struct rtc_time));
 390	rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL,
 391			      SMU_CMD_RTC_GET_DATETIME);
 392	if (rc)
 393		return rc;
 394	smu_spinwait_simple(&cmd);
 395
 396	time->tm_sec = bcd2hex(cmd.buffer[0]);
 397	time->tm_min = bcd2hex(cmd.buffer[1]);
 398	time->tm_hour = bcd2hex(cmd.buffer[2]);
 399	time->tm_wday = bcd2hex(cmd.buffer[3]);
 400	time->tm_mday = bcd2hex(cmd.buffer[4]);
 401	time->tm_mon = bcd2hex(cmd.buffer[5]) - 1;
 402	time->tm_year = bcd2hex(cmd.buffer[6]) + 100;
 403
 404	return 0;
 405}
 406
 407
 408int smu_set_rtc_time(struct rtc_time *time, int spinwait)
 409{
 410	struct smu_simple_cmd cmd;
 411	int rc;
 412
 413	if (smu == NULL)
 414		return -ENODEV;
 415
 416	rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL,
 417			      SMU_CMD_RTC_SET_DATETIME,
 418			      hex2bcd(time->tm_sec),
 419			      hex2bcd(time->tm_min),
 420			      hex2bcd(time->tm_hour),
 421			      time->tm_wday,
 422			      hex2bcd(time->tm_mday),
 423			      hex2bcd(time->tm_mon) + 1,
 424			      hex2bcd(time->tm_year - 100));
 425	if (rc)
 426		return rc;
 427	smu_spinwait_simple(&cmd);
 428
 429	return 0;
 430}
 431
 432
 433void smu_shutdown(void)
 434{
 435	struct smu_simple_cmd cmd;
 436
 437	if (smu == NULL)
 438		return;
 439
 440	if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL,
 441			     'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0))
 442		return;
 443	smu_spinwait_simple(&cmd);
 444	for (;;)
 445		;
 446}
 447
 448
 449void smu_restart(void)
 450{
 451	struct smu_simple_cmd cmd;
 452
 453	if (smu == NULL)
 454		return;
 455
 456	if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL,
 457			     'R', 'E', 'S', 'T', 'A', 'R', 'T', 0))
 458		return;
 459	smu_spinwait_simple(&cmd);
 460	for (;;)
 461		;
 462}
 463
 464
 465int smu_present(void)
 466{
 467	return smu != NULL;
 468}
 469EXPORT_SYMBOL(smu_present);
 470
 471
 472int __init smu_init (void)
 473{
 474	struct device_node *np;
 475	const u32 *data;
 476	int ret = 0;
 477
 478        np = of_find_node_by_type(NULL, "smu");
 479        if (np == NULL)
 480		return -ENODEV;
 481
 482	printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR);
 483
 484	/*
 485	 * SMU based G5s need some memory below 2Gb. Thankfully this is
 486	 * called at a time where memblock is still available.
 487	 */
 488	smu_cmdbuf_abs = memblock_alloc_base(4096, 4096, 0x80000000UL);
 489	if (smu_cmdbuf_abs == 0) {
 490		printk(KERN_ERR "SMU: Command buffer allocation failed !\n");
 491		ret = -EINVAL;
 492		goto fail_np;
 493	}
 494
 495	smu = alloc_bootmem(sizeof(struct smu_device));
 496
 497	spin_lock_init(&smu->lock);
 498	INIT_LIST_HEAD(&smu->cmd_list);
 499	INIT_LIST_HEAD(&smu->cmd_i2c_list);
 500	smu->of_node = np;
 501	smu->db_irq = 0;
 502	smu->msg_irq = 0;
 503
 504	/* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a
 505	 * 32 bits value safely
 506	 */
 507	smu->cmd_buf_abs = (u32)smu_cmdbuf_abs;
 508	smu->cmd_buf = __va(smu_cmdbuf_abs);
 509
 510	smu->db_node = of_find_node_by_name(NULL, "smu-doorbell");
 511	if (smu->db_node == NULL) {
 512		printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n");
 513		ret = -ENXIO;
 514		goto fail_bootmem;
 515	}
 516	data = of_get_property(smu->db_node, "reg", NULL);
 517	if (data == NULL) {
 518		printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n");
 519		ret = -ENXIO;
 520		goto fail_db_node;
 521	}
 522
 523	/* Current setup has one doorbell GPIO that does both doorbell
 524	 * and ack. GPIOs are at 0x50, best would be to find that out
 525	 * in the device-tree though.
 526	 */
 527	smu->doorbell = *data;
 528	if (smu->doorbell < 0x50)
 529		smu->doorbell += 0x50;
 530
 531	/* Now look for the smu-interrupt GPIO */
 532	do {
 533		smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt");
 534		if (smu->msg_node == NULL)
 535			break;
 536		data = of_get_property(smu->msg_node, "reg", NULL);
 537		if (data == NULL) {
 538			of_node_put(smu->msg_node);
 539			smu->msg_node = NULL;
 540			break;
 541		}
 542		smu->msg = *data;
 543		if (smu->msg < 0x50)
 544			smu->msg += 0x50;
 545	} while(0);
 546
 547	/* Doorbell buffer is currently hard-coded, I didn't find a proper
 548	 * device-tree entry giving the address. Best would probably to use
 549	 * an offset for K2 base though, but let's do it that way for now.
 550	 */
 551	smu->db_buf = ioremap(0x8000860c, 0x1000);
 552	if (smu->db_buf == NULL) {
 553		printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n");
 554		ret = -ENXIO;
 555		goto fail_msg_node;
 556	}
 557
 558	/* U3 has an issue with NAP mode when issuing SMU commands */
 559	smu->broken_nap = pmac_get_uninorth_variant() < 4;
 560	if (smu->broken_nap)
 561		printk(KERN_INFO "SMU: using NAP mode workaround\n");
 562
 563	sys_ctrler = SYS_CTRLER_SMU;
 564	return 0;
 565
 566fail_msg_node:
 567	of_node_put(smu->msg_node);
 
 568fail_db_node:
 569	of_node_put(smu->db_node);
 570fail_bootmem:
 571	free_bootmem(__pa(smu), sizeof(struct smu_device));
 572	smu = NULL;
 573fail_np:
 574	of_node_put(np);
 575	return ret;
 576}
 577
 578
 579static int smu_late_init(void)
 580{
 581	if (!smu)
 582		return 0;
 583
 584	init_timer(&smu->i2c_timer);
 585	smu->i2c_timer.function = smu_i2c_retry;
 586	smu->i2c_timer.data = (unsigned long)smu;
 587
 588	if (smu->db_node) {
 589		smu->db_irq = irq_of_parse_and_map(smu->db_node, 0);
 590		if (!smu->db_irq)
 591			printk(KERN_ERR "smu: failed to map irq for node %s\n",
 592			       smu->db_node->full_name);
 593	}
 594	if (smu->msg_node) {
 595		smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0);
 596		if (!smu->msg_irq)
 597			printk(KERN_ERR "smu: failed to map irq for node %s\n",
 598			       smu->msg_node->full_name);
 599	}
 600
 601	/*
 602	 * Try to request the interrupts
 603	 */
 604
 605	if (smu->db_irq) {
 606		if (request_irq(smu->db_irq, smu_db_intr,
 607				IRQF_SHARED, "SMU doorbell", smu) < 0) {
 608			printk(KERN_WARNING "SMU: can't "
 609			       "request interrupt %d\n",
 610			       smu->db_irq);
 611			smu->db_irq = 0;
 612		}
 613	}
 614
 615	if (smu->msg_irq) {
 616		if (request_irq(smu->msg_irq, smu_msg_intr,
 617				IRQF_SHARED, "SMU message", smu) < 0) {
 618			printk(KERN_WARNING "SMU: can't "
 619			       "request interrupt %d\n",
 620			       smu->msg_irq);
 621			smu->msg_irq = 0;
 622		}
 623	}
 624
 625	smu_irq_inited = 1;
 626	return 0;
 627}
 628/* This has to be before arch_initcall as the low i2c stuff relies on the
 629 * above having been done before we reach arch_initcalls
 630 */
 631core_initcall(smu_late_init);
 632
 633/*
 634 * sysfs visibility
 635 */
 636
 637static void smu_expose_childs(struct work_struct *unused)
 638{
 639	struct device_node *np;
 640
 641	for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;)
 642		if (of_device_is_compatible(np, "smu-sensors"))
 643			of_platform_device_create(np, "smu-sensors",
 644						  &smu->of_dev->dev);
 645}
 646
 647static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs);
 648
 649static int smu_platform_probe(struct platform_device* dev)
 650{
 651	if (!smu)
 652		return -ENODEV;
 653	smu->of_dev = dev;
 654
 655	/*
 656	 * Ok, we are matched, now expose all i2c busses. We have to defer
 657	 * that unfortunately or it would deadlock inside the device model
 658	 */
 659	schedule_work(&smu_expose_childs_work);
 660
 661	return 0;
 662}
 663
 664static const struct of_device_id smu_platform_match[] =
 665{
 666	{
 667		.type		= "smu",
 668	},
 669	{},
 670};
 671
 672static struct platform_driver smu_of_platform_driver =
 673{
 674	.driver = {
 675		.name = "smu",
 
 676		.of_match_table = smu_platform_match,
 677	},
 678	.probe		= smu_platform_probe,
 679};
 680
 681static int __init smu_init_sysfs(void)
 682{
 683	/*
 
 
 
 684	 * For now, we don't power manage machines with an SMU chip,
 685	 * I'm a bit too far from figuring out how that works with those
 686	 * new chipsets, but that will come back and bite us
 687	 */
 688	platform_driver_register(&smu_of_platform_driver);
 689	return 0;
 690}
 691
 692device_initcall(smu_init_sysfs);
 693
 694struct platform_device *smu_get_ofdev(void)
 695{
 696	if (!smu)
 697		return NULL;
 698	return smu->of_dev;
 699}
 700
 701EXPORT_SYMBOL_GPL(smu_get_ofdev);
 702
 703/*
 704 * i2c interface
 705 */
 706
 707static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail)
 708{
 709	void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done;
 710	void *misc = cmd->misc;
 711	unsigned long flags;
 712
 713	/* Check for read case */
 714	if (!fail && cmd->read) {
 715		if (cmd->pdata[0] < 1)
 716			fail = 1;
 717		else
 718			memcpy(cmd->info.data, &cmd->pdata[1],
 719			       cmd->info.datalen);
 720	}
 721
 722	DPRINTK("SMU: completing, success: %d\n", !fail);
 723
 724	/* Update status and mark no pending i2c command with lock
 725	 * held so nobody comes in while we dequeue an eventual
 726	 * pending next i2c command
 727	 */
 728	spin_lock_irqsave(&smu->lock, flags);
 729	smu->cmd_i2c_cur = NULL;
 730	wmb();
 731	cmd->status = fail ? -EIO : 0;
 732
 733	/* Is there another i2c command waiting ? */
 734	if (!list_empty(&smu->cmd_i2c_list)) {
 735		struct smu_i2c_cmd *newcmd;
 736
 737		/* Fetch it, new current, remove from list */
 738		newcmd = list_entry(smu->cmd_i2c_list.next,
 739				    struct smu_i2c_cmd, link);
 740		smu->cmd_i2c_cur = newcmd;
 741		list_del(&cmd->link);
 742
 743		/* Queue with low level smu */
 744		list_add_tail(&cmd->scmd.link, &smu->cmd_list);
 745		if (smu->cmd_cur == NULL)
 746			smu_start_cmd();
 747	}
 748	spin_unlock_irqrestore(&smu->lock, flags);
 749
 750	/* Call command completion handler if any */
 751	if (done)
 752		done(cmd, misc);
 753
 754}
 755
 756
 757static void smu_i2c_retry(unsigned long data)
 758{
 759	struct smu_i2c_cmd	*cmd = smu->cmd_i2c_cur;
 760
 761	DPRINTK("SMU: i2c failure, requeuing...\n");
 762
 763	/* requeue command simply by resetting reply_len */
 764	cmd->pdata[0] = 0xff;
 765	cmd->scmd.reply_len = sizeof(cmd->pdata);
 766	smu_queue_cmd(&cmd->scmd);
 767}
 768
 769
 770static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc)
 771{
 772	struct smu_i2c_cmd	*cmd = misc;
 773	int			fail = 0;
 774
 775	DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n",
 776		cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len);
 777
 778	/* Check for possible status */
 779	if (scmd->status < 0)
 780		fail = 1;
 781	else if (cmd->read) {
 782		if (cmd->stage == 0)
 783			fail = cmd->pdata[0] != 0;
 784		else
 785			fail = cmd->pdata[0] >= 0x80;
 786	} else {
 787		fail = cmd->pdata[0] != 0;
 788	}
 789
 790	/* Handle failures by requeuing command, after 5ms interval
 791	 */
 792	if (fail && --cmd->retries > 0) {
 793		DPRINTK("SMU: i2c failure, starting timer...\n");
 794		BUG_ON(cmd != smu->cmd_i2c_cur);
 795		if (!smu_irq_inited) {
 796			mdelay(5);
 797			smu_i2c_retry(0);
 798			return;
 799		}
 800		mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5));
 801		return;
 802	}
 803
 804	/* If failure or stage 1, command is complete */
 805	if (fail || cmd->stage != 0) {
 806		smu_i2c_complete_command(cmd, fail);
 807		return;
 808	}
 809
 810	DPRINTK("SMU: going to stage 1\n");
 811
 812	/* Ok, initial command complete, now poll status */
 813	scmd->reply_buf = cmd->pdata;
 814	scmd->reply_len = sizeof(cmd->pdata);
 815	scmd->data_buf = cmd->pdata;
 816	scmd->data_len = 1;
 817	cmd->pdata[0] = 0;
 818	cmd->stage = 1;
 819	cmd->retries = 20;
 820	smu_queue_cmd(scmd);
 821}
 822
 823
 824int smu_queue_i2c(struct smu_i2c_cmd *cmd)
 825{
 826	unsigned long flags;
 827
 828	if (smu == NULL)
 829		return -ENODEV;
 830
 831	/* Fill most fields of scmd */
 832	cmd->scmd.cmd = SMU_CMD_I2C_COMMAND;
 833	cmd->scmd.done = smu_i2c_low_completion;
 834	cmd->scmd.misc = cmd;
 835	cmd->scmd.reply_buf = cmd->pdata;
 836	cmd->scmd.reply_len = sizeof(cmd->pdata);
 837	cmd->scmd.data_buf = (u8 *)(char *)&cmd->info;
 838	cmd->scmd.status = 1;
 839	cmd->stage = 0;
 840	cmd->pdata[0] = 0xff;
 841	cmd->retries = 20;
 842	cmd->status = 1;
 843
 844	/* Check transfer type, sanitize some "info" fields
 845	 * based on transfer type and do more checking
 846	 */
 847	cmd->info.caddr = cmd->info.devaddr;
 848	cmd->read = cmd->info.devaddr & 0x01;
 849	switch(cmd->info.type) {
 850	case SMU_I2C_TRANSFER_SIMPLE:
 851		memset(&cmd->info.sublen, 0, 4);
 852		break;
 853	case SMU_I2C_TRANSFER_COMBINED:
 854		cmd->info.devaddr &= 0xfe;
 855	case SMU_I2C_TRANSFER_STDSUB:
 856		if (cmd->info.sublen > 3)
 857			return -EINVAL;
 858		break;
 859	default:
 860		return -EINVAL;
 861	}
 862
 863	/* Finish setting up command based on transfer direction
 864	 */
 865	if (cmd->read) {
 866		if (cmd->info.datalen > SMU_I2C_READ_MAX)
 867			return -EINVAL;
 868		memset(cmd->info.data, 0xff, cmd->info.datalen);
 869		cmd->scmd.data_len = 9;
 870	} else {
 871		if (cmd->info.datalen > SMU_I2C_WRITE_MAX)
 872			return -EINVAL;
 873		cmd->scmd.data_len = 9 + cmd->info.datalen;
 874	}
 875
 876	DPRINTK("SMU: i2c enqueuing command\n");
 877	DPRINTK("SMU:   %s, len=%d bus=%x addr=%x sub0=%x type=%x\n",
 878		cmd->read ? "read" : "write", cmd->info.datalen,
 879		cmd->info.bus, cmd->info.caddr,
 880		cmd->info.subaddr[0], cmd->info.type);
 881
 882
 883	/* Enqueue command in i2c list, and if empty, enqueue also in
 884	 * main command list
 885	 */
 886	spin_lock_irqsave(&smu->lock, flags);
 887	if (smu->cmd_i2c_cur == NULL) {
 888		smu->cmd_i2c_cur = cmd;
 889		list_add_tail(&cmd->scmd.link, &smu->cmd_list);
 890		if (smu->cmd_cur == NULL)
 891			smu_start_cmd();
 892	} else
 893		list_add_tail(&cmd->link, &smu->cmd_i2c_list);
 894	spin_unlock_irqrestore(&smu->lock, flags);
 895
 896	return 0;
 897}
 898
 899/*
 900 * Handling of "partitions"
 901 */
 902
 903static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len)
 904{
 905	DECLARE_COMPLETION_ONSTACK(comp);
 906	unsigned int chunk;
 907	struct smu_cmd cmd;
 908	int rc;
 909	u8 params[8];
 910
 911	/* We currently use a chunk size of 0xe. We could check the
 912	 * SMU firmware version and use bigger sizes though
 913	 */
 914	chunk = 0xe;
 915
 916	while (len) {
 917		unsigned int clen = min(len, chunk);
 918
 919		cmd.cmd = SMU_CMD_MISC_ee_COMMAND;
 920		cmd.data_len = 7;
 921		cmd.data_buf = params;
 922		cmd.reply_len = chunk;
 923		cmd.reply_buf = dest;
 924		cmd.done = smu_done_complete;
 925		cmd.misc = &comp;
 926		params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC;
 927		params[1] = 0x4;
 928		*((u32 *)&params[2]) = addr;
 929		params[6] = clen;
 930
 931		rc = smu_queue_cmd(&cmd);
 932		if (rc)
 933			return rc;
 934		wait_for_completion(&comp);
 935		if (cmd.status != 0)
 936			return rc;
 937		if (cmd.reply_len != clen) {
 938			printk(KERN_DEBUG "SMU: short read in "
 939			       "smu_read_datablock, got: %d, want: %d\n",
 940			       cmd.reply_len, clen);
 941			return -EIO;
 942		}
 943		len -= clen;
 944		addr += clen;
 945		dest += clen;
 946	}
 947	return 0;
 948}
 949
 950static struct smu_sdbp_header *smu_create_sdb_partition(int id)
 951{
 952	DECLARE_COMPLETION_ONSTACK(comp);
 953	struct smu_simple_cmd cmd;
 954	unsigned int addr, len, tlen;
 955	struct smu_sdbp_header *hdr;
 956	struct property *prop;
 957
 958	/* First query the partition info */
 959	DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq);
 960	smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2,
 961			 smu_done_complete, &comp,
 962			 SMU_CMD_PARTITION_LATEST, id);
 963	wait_for_completion(&comp);
 964	DPRINTK("SMU: done, status: %d, reply_len: %d\n",
 965		cmd.cmd.status, cmd.cmd.reply_len);
 966
 967	/* Partition doesn't exist (or other error) */
 968	if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6)
 969		return NULL;
 970
 971	/* Fetch address and length from reply */
 972	addr = *((u16 *)cmd.buffer);
 973	len = cmd.buffer[3] << 2;
 974	/* Calucluate total length to allocate, including the 17 bytes
 975	 * for "sdb-partition-XX" that we append at the end of the buffer
 976	 */
 977	tlen = sizeof(struct property) + len + 18;
 978
 979	prop = kzalloc(tlen, GFP_KERNEL);
 980	if (prop == NULL)
 981		return NULL;
 982	hdr = (struct smu_sdbp_header *)(prop + 1);
 983	prop->name = ((char *)prop) + tlen - 18;
 984	sprintf(prop->name, "sdb-partition-%02x", id);
 985	prop->length = len;
 986	prop->value = hdr;
 987	prop->next = NULL;
 988
 989	/* Read the datablock */
 990	if (smu_read_datablock((u8 *)hdr, addr, len)) {
 991		printk(KERN_DEBUG "SMU: datablock read failed while reading "
 992		       "partition %02x !\n", id);
 993		goto failure;
 994	}
 995
 996	/* Got it, check a few things and create the property */
 997	if (hdr->id != id) {
 998		printk(KERN_DEBUG "SMU: Reading partition %02x and got "
 999		       "%02x !\n", id, hdr->id);
1000		goto failure;
1001	}
1002	if (of_add_property(smu->of_node, prop)) {
1003		printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x "
1004		       "property !\n", id);
1005		goto failure;
1006	}
1007
1008	return hdr;
1009 failure:
1010	kfree(prop);
1011	return NULL;
1012}
1013
1014/* Note: Only allowed to return error code in pointers (using ERR_PTR)
1015 * when interruptible is 1
1016 */
1017const struct smu_sdbp_header *__smu_get_sdb_partition(int id,
1018		unsigned int *size, int interruptible)
1019{
1020	char pname[32];
1021	const struct smu_sdbp_header *part;
1022
1023	if (!smu)
1024		return NULL;
1025
1026	sprintf(pname, "sdb-partition-%02x", id);
1027
1028	DPRINTK("smu_get_sdb_partition(%02x)\n", id);
1029
1030	if (interruptible) {
1031		int rc;
1032		rc = mutex_lock_interruptible(&smu_part_access);
1033		if (rc)
1034			return ERR_PTR(rc);
1035	} else
1036		mutex_lock(&smu_part_access);
1037
1038	part = of_get_property(smu->of_node, pname, size);
1039	if (part == NULL) {
1040		DPRINTK("trying to extract from SMU ...\n");
1041		part = smu_create_sdb_partition(id);
1042		if (part != NULL && size)
1043			*size = part->len << 2;
1044	}
1045	mutex_unlock(&smu_part_access);
1046	return part;
1047}
1048
1049const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size)
1050{
1051	return __smu_get_sdb_partition(id, size, 0);
1052}
1053EXPORT_SYMBOL(smu_get_sdb_partition);
1054
1055
1056/*
1057 * Userland driver interface
1058 */
1059
1060
1061static LIST_HEAD(smu_clist);
1062static DEFINE_SPINLOCK(smu_clist_lock);
1063
1064enum smu_file_mode {
1065	smu_file_commands,
1066	smu_file_events,
1067	smu_file_closing
1068};
1069
1070struct smu_private
1071{
1072	struct list_head	list;
1073	enum smu_file_mode	mode;
1074	int			busy;
1075	struct smu_cmd		cmd;
1076	spinlock_t		lock;
1077	wait_queue_head_t	wait;
1078	u8			buffer[SMU_MAX_DATA];
1079};
1080
1081
1082static int smu_open(struct inode *inode, struct file *file)
1083{
1084	struct smu_private *pp;
1085	unsigned long flags;
1086
1087	pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL);
1088	if (pp == 0)
1089		return -ENOMEM;
1090	spin_lock_init(&pp->lock);
1091	pp->mode = smu_file_commands;
1092	init_waitqueue_head(&pp->wait);
1093
1094	mutex_lock(&smu_mutex);
1095	spin_lock_irqsave(&smu_clist_lock, flags);
1096	list_add(&pp->list, &smu_clist);
1097	spin_unlock_irqrestore(&smu_clist_lock, flags);
1098	file->private_data = pp;
1099	mutex_unlock(&smu_mutex);
1100
1101	return 0;
1102}
1103
1104
1105static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc)
1106{
1107	struct smu_private *pp = misc;
1108
1109	wake_up_all(&pp->wait);
1110}
1111
1112
1113static ssize_t smu_write(struct file *file, const char __user *buf,
1114			 size_t count, loff_t *ppos)
1115{
1116	struct smu_private *pp = file->private_data;
1117	unsigned long flags;
1118	struct smu_user_cmd_hdr hdr;
1119	int rc = 0;
1120
1121	if (pp->busy)
1122		return -EBUSY;
1123	else if (copy_from_user(&hdr, buf, sizeof(hdr)))
1124		return -EFAULT;
1125	else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) {
1126		pp->mode = smu_file_events;
1127		return 0;
1128	} else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) {
1129		const struct smu_sdbp_header *part;
1130		part = __smu_get_sdb_partition(hdr.cmd, NULL, 1);
1131		if (part == NULL)
1132			return -EINVAL;
1133		else if (IS_ERR(part))
1134			return PTR_ERR(part);
1135		return 0;
1136	} else if (hdr.cmdtype != SMU_CMDTYPE_SMU)
1137		return -EINVAL;
1138	else if (pp->mode != smu_file_commands)
1139		return -EBADFD;
1140	else if (hdr.data_len > SMU_MAX_DATA)
1141		return -EINVAL;
1142
1143	spin_lock_irqsave(&pp->lock, flags);
1144	if (pp->busy) {
1145		spin_unlock_irqrestore(&pp->lock, flags);
1146		return -EBUSY;
1147	}
1148	pp->busy = 1;
1149	pp->cmd.status = 1;
1150	spin_unlock_irqrestore(&pp->lock, flags);
1151
1152	if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) {
1153		pp->busy = 0;
1154		return -EFAULT;
1155	}
1156
1157	pp->cmd.cmd = hdr.cmd;
1158	pp->cmd.data_len = hdr.data_len;
1159	pp->cmd.reply_len = SMU_MAX_DATA;
1160	pp->cmd.data_buf = pp->buffer;
1161	pp->cmd.reply_buf = pp->buffer;
1162	pp->cmd.done = smu_user_cmd_done;
1163	pp->cmd.misc = pp;
1164	rc = smu_queue_cmd(&pp->cmd);
1165	if (rc < 0)
1166		return rc;
1167	return count;
1168}
1169
1170
1171static ssize_t smu_read_command(struct file *file, struct smu_private *pp,
1172				char __user *buf, size_t count)
1173{
1174	DECLARE_WAITQUEUE(wait, current);
1175	struct smu_user_reply_hdr hdr;
1176	unsigned long flags;
1177	int size, rc = 0;
1178
1179	if (!pp->busy)
1180		return 0;
1181	if (count < sizeof(struct smu_user_reply_hdr))
1182		return -EOVERFLOW;
1183	spin_lock_irqsave(&pp->lock, flags);
1184	if (pp->cmd.status == 1) {
1185		if (file->f_flags & O_NONBLOCK) {
1186			spin_unlock_irqrestore(&pp->lock, flags);
1187			return -EAGAIN;
1188		}
1189		add_wait_queue(&pp->wait, &wait);
1190		for (;;) {
1191			set_current_state(TASK_INTERRUPTIBLE);
1192			rc = 0;
1193			if (pp->cmd.status != 1)
1194				break;
1195			rc = -ERESTARTSYS;
1196			if (signal_pending(current))
1197				break;
1198			spin_unlock_irqrestore(&pp->lock, flags);
1199			schedule();
1200			spin_lock_irqsave(&pp->lock, flags);
1201		}
1202		set_current_state(TASK_RUNNING);
1203		remove_wait_queue(&pp->wait, &wait);
1204	}
1205	spin_unlock_irqrestore(&pp->lock, flags);
1206	if (rc)
1207		return rc;
1208	if (pp->cmd.status != 0)
1209		pp->cmd.reply_len = 0;
1210	size = sizeof(hdr) + pp->cmd.reply_len;
1211	if (count < size)
1212		size = count;
1213	rc = size;
1214	hdr.status = pp->cmd.status;
1215	hdr.reply_len = pp->cmd.reply_len;
1216	if (copy_to_user(buf, &hdr, sizeof(hdr)))
1217		return -EFAULT;
1218	size -= sizeof(hdr);
1219	if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size))
1220		return -EFAULT;
1221	pp->busy = 0;
1222
1223	return rc;
1224}
1225
1226
1227static ssize_t smu_read_events(struct file *file, struct smu_private *pp,
1228			       char __user *buf, size_t count)
1229{
1230	/* Not implemented */
1231	msleep_interruptible(1000);
1232	return 0;
1233}
1234
1235
1236static ssize_t smu_read(struct file *file, char __user *buf,
1237			size_t count, loff_t *ppos)
1238{
1239	struct smu_private *pp = file->private_data;
1240
1241	if (pp->mode == smu_file_commands)
1242		return smu_read_command(file, pp, buf, count);
1243	if (pp->mode == smu_file_events)
1244		return smu_read_events(file, pp, buf, count);
1245
1246	return -EBADFD;
1247}
1248
1249static unsigned int smu_fpoll(struct file *file, poll_table *wait)
1250{
1251	struct smu_private *pp = file->private_data;
1252	unsigned int mask = 0;
1253	unsigned long flags;
1254
1255	if (pp == 0)
1256		return 0;
1257
1258	if (pp->mode == smu_file_commands) {
1259		poll_wait(file, &pp->wait, wait);
1260
1261		spin_lock_irqsave(&pp->lock, flags);
1262		if (pp->busy && pp->cmd.status != 1)
1263			mask |= POLLIN;
1264		spin_unlock_irqrestore(&pp->lock, flags);
1265	}
1266	if (pp->mode == smu_file_events) {
1267		/* Not yet implemented */
1268	}
1269	return mask;
1270}
1271
1272static int smu_release(struct inode *inode, struct file *file)
1273{
1274	struct smu_private *pp = file->private_data;
1275	unsigned long flags;
1276	unsigned int busy;
1277
1278	if (pp == 0)
1279		return 0;
1280
1281	file->private_data = NULL;
1282
1283	/* Mark file as closing to avoid races with new request */
1284	spin_lock_irqsave(&pp->lock, flags);
1285	pp->mode = smu_file_closing;
1286	busy = pp->busy;
1287
1288	/* Wait for any pending request to complete */
1289	if (busy && pp->cmd.status == 1) {
1290		DECLARE_WAITQUEUE(wait, current);
1291
1292		add_wait_queue(&pp->wait, &wait);
1293		for (;;) {
1294			set_current_state(TASK_UNINTERRUPTIBLE);
1295			if (pp->cmd.status != 1)
1296				break;
1297			spin_unlock_irqrestore(&pp->lock, flags);
1298			schedule();
1299			spin_lock_irqsave(&pp->lock, flags);
1300		}
1301		set_current_state(TASK_RUNNING);
1302		remove_wait_queue(&pp->wait, &wait);
1303	}
1304	spin_unlock_irqrestore(&pp->lock, flags);
1305
1306	spin_lock_irqsave(&smu_clist_lock, flags);
1307	list_del(&pp->list);
1308	spin_unlock_irqrestore(&smu_clist_lock, flags);
1309	kfree(pp);
1310
1311	return 0;
1312}
1313
1314
1315static const struct file_operations smu_device_fops = {
1316	.llseek		= no_llseek,
1317	.read		= smu_read,
1318	.write		= smu_write,
1319	.poll		= smu_fpoll,
1320	.open		= smu_open,
1321	.release	= smu_release,
1322};
1323
1324static struct miscdevice pmu_device = {
1325	MISC_DYNAMIC_MINOR, "smu", &smu_device_fops
1326};
1327
1328static int smu_device_init(void)
1329{
1330	if (!smu)
1331		return -ENODEV;
1332	if (misc_register(&pmu_device) < 0)
1333		printk(KERN_ERR "via-pmu: cannot register misc device.\n");
1334	return 0;
1335}
1336device_initcall(smu_device_init);