1/*
   2 * RapidIO enumeration and discovery support
   3 *
   4 * Copyright 2005 MontaVista Software, Inc.
   5 * Matt Porter <mporter@kernel.crashing.org>
   6 *
   7 * Copyright 2009 Integrated Device Technology, Inc.
   8 * Alex Bounine <alexandre.bounine@idt.com>
   9 * - Added Port-Write/Error Management initialization and handling
  10 *
  11 * Copyright 2009 Sysgo AG
  12 * Thomas Moll <thomas.moll@sysgo.com>
  13 * - Added Input- Output- enable functionality, to allow full communication
  14 *
  15 * This program is free software; you can redistribute  it and/or modify it
  16 * under  the terms of  the GNU General  Public License as published by the
  17 * Free Software Foundation;  either version 2 of the  License, or (at your
  18 * option) any later version.
  19 */
  20
  21#include <linux/types.h>
  22#include <linux/kernel.h>
  23
  24#include <linux/delay.h>
  25#include <linux/dma-mapping.h>
  26#include <linux/init.h>
  27#include <linux/rio.h>
  28#include <linux/rio_drv.h>
  29#include <linux/rio_ids.h>
  30#include <linux/rio_regs.h>
  31#include <linux/module.h>
  32#include <linux/spinlock.h>
  33#include <linux/timer.h>
  34#include <linux/sched.h>
  35#include <linux/jiffies.h>
  36#include <linux/slab.h>
  37
  38#include "rio.h"
  39
  40static void rio_init_em(struct rio_dev *rdev);
  41
  42struct rio_id_table {
  43	u16 start;	/* logical minimal id */
  44	u32 max;	/* max number of IDs in table */
  45	spinlock_t lock;
  46	unsigned long table[0];
  47};
  48
  49static int next_destid = 0;
  50static int next_comptag = 1;
  51
  52static int rio_mport_phys_table[] = {
  53	RIO_EFB_PAR_EP_ID,
  54	RIO_EFB_PAR_EP_REC_ID,
  55	RIO_EFB_SER_EP_ID,
  56	RIO_EFB_SER_EP_REC_ID,
  57	-1,
  58};
  59
  60
  61/**
  62 * rio_destid_alloc - Allocate next available destID for given network
  63 * @net: RIO network
  64 *
  65 * Returns next available device destination ID for the specified RIO network.
  66 * Marks allocated ID as one in use.
  67 * Returns RIO_INVALID_DESTID if new destID is not available.
  68 */
  69static u16 rio_destid_alloc(struct rio_net *net)
  70{
  71	int destid;
  72	struct rio_id_table *idtab = (struct rio_id_table *)net->enum_data;
  73
  74	spin_lock(&idtab->lock);
  75	destid = find_first_zero_bit(idtab->table, idtab->max);
  76
  77	if (destid < idtab->max) {
  78		set_bit(destid, idtab->table);
  79		destid += idtab->start;
  80	} else
  81		destid = RIO_INVALID_DESTID;
  82
  83	spin_unlock(&idtab->lock);
  84	return (u16)destid;
  85}
  86
  87/**
  88 * rio_destid_reserve - Reserve the specivied destID
  89 * @net: RIO network
  90 * @destid: destID to reserve
  91 *
  92 * Tries to reserve the specified destID.
  93 * Returns 0 if successful.
  94 */
  95static int rio_destid_reserve(struct rio_net *net, u16 destid)
  96{
  97	int oldbit;
  98	struct rio_id_table *idtab = (struct rio_id_table *)net->enum_data;
  99
 100	destid -= idtab->start;
 101	spin_lock(&idtab->lock);
 102	oldbit = test_and_set_bit(destid, idtab->table);
 103	spin_unlock(&idtab->lock);
 104	return oldbit;
 105}
 106
 107/**
 108 * rio_destid_free - free a previously allocated destID
 109 * @net: RIO network
 110 * @destid: destID to free
 111 *
 112 * Makes the specified destID available for use.
 113 */
 114static void rio_destid_free(struct rio_net *net, u16 destid)
 115{
 116	struct rio_id_table *idtab = (struct rio_id_table *)net->enum_data;
 117
 118	destid -= idtab->start;
 119	spin_lock(&idtab->lock);
 120	clear_bit(destid, idtab->table);
 121	spin_unlock(&idtab->lock);
 122}
 123
 124/**
 125 * rio_destid_first - return first destID in use
 126 * @net: RIO network
 127 */
 128static u16 rio_destid_first(struct rio_net *net)
 129{
 130	int destid;
 131	struct rio_id_table *idtab = (struct rio_id_table *)net->enum_data;
 132
 133	spin_lock(&idtab->lock);
 134	destid = find_first_bit(idtab->table, idtab->max);
 135	if (destid >= idtab->max)
 136		destid = RIO_INVALID_DESTID;
 137	else
 138		destid += idtab->start;
 139	spin_unlock(&idtab->lock);
 140	return (u16)destid;
 141}
 142
 143/**
 144 * rio_destid_next - return next destID in use
 145 * @net: RIO network
 146 * @from: destination ID from which search shall continue
 147 */
 148static u16 rio_destid_next(struct rio_net *net, u16 from)
 149{
 150	int destid;
 151	struct rio_id_table *idtab = (struct rio_id_table *)net->enum_data;
 152
 153	spin_lock(&idtab->lock);
 154	destid = find_next_bit(idtab->table, idtab->max, from);
 155	if (destid >= idtab->max)
 156		destid = RIO_INVALID_DESTID;
 157	else
 158		destid += idtab->start;
 159	spin_unlock(&idtab->lock);
 160	return (u16)destid;
 161}
 162
 163/**
 164 * rio_get_device_id - Get the base/extended device id for a device
 165 * @port: RIO master port
 166 * @destid: Destination ID of device
 167 * @hopcount: Hopcount to device
 168 *
 169 * Reads the base/extended device id from a device. Returns the
 170 * 8/16-bit device ID.
 171 */
 172static u16 rio_get_device_id(struct rio_mport *port, u16 destid, u8 hopcount)
 173{
 174	u32 result;
 175
 176	rio_mport_read_config_32(port, destid, hopcount, RIO_DID_CSR, &result);
 177
 178	return RIO_GET_DID(port->sys_size, result);
 179}
 180
 181/**
 182 * rio_set_device_id - Set the base/extended device id for a device
 183 * @port: RIO master port
 184 * @destid: Destination ID of device
 185 * @hopcount: Hopcount to device
 186 * @did: Device ID value to be written
 187 *
 188 * Writes the base/extended device id from a device.
 189 */
 190static void rio_set_device_id(struct rio_mport *port, u16 destid, u8 hopcount, u16 did)
 191{
 192	rio_mport_write_config_32(port, destid, hopcount, RIO_DID_CSR,
 193				  RIO_SET_DID(port->sys_size, did));
 194}
 195
 196/**
 197 * rio_clear_locks- Release all host locks and signal enumeration complete
 198 * @net: RIO network to run on
 199 *
 200 * Marks the component tag CSR on each device with the enumeration
 201 * complete flag. When complete, it then release the host locks on
 202 * each device. Returns 0 on success or %-EINVAL on failure.
 203 */
 204static int rio_clear_locks(struct rio_net *net)
 205{
 206	struct rio_mport *port = net->hport;
 207	struct rio_dev *rdev;
 208	u32 result;
 209	int ret = 0;
 210
 211	/* Release host device id locks */
 212	rio_local_write_config_32(port, RIO_HOST_DID_LOCK_CSR,
 213				  port->host_deviceid);
 214	rio_local_read_config_32(port, RIO_HOST_DID_LOCK_CSR, &result);
 215	if ((result & 0xffff) != 0xffff) {
 216		printk(KERN_INFO
 217		       "RIO: badness when releasing host lock on master port, result %8.8x\n",
 218		       result);
 219		ret = -EINVAL;
 220	}
 221	list_for_each_entry(rdev, &net->devices, net_list) {
 222		rio_write_config_32(rdev, RIO_HOST_DID_LOCK_CSR,
 223				    port->host_deviceid);
 224		rio_read_config_32(rdev, RIO_HOST_DID_LOCK_CSR, &result);
 225		if ((result & 0xffff) != 0xffff) {
 226			printk(KERN_INFO
 227			       "RIO: badness when releasing host lock on vid %4.4x did %4.4x\n",
 228			       rdev->vid, rdev->did);
 229			ret = -EINVAL;
 230		}
 231
 232		/* Mark device as discovered and enable master */
 233		rio_read_config_32(rdev,
 234				   rdev->phys_efptr + RIO_PORT_GEN_CTL_CSR,
 235				   &result);
 236		result |= RIO_PORT_GEN_DISCOVERED | RIO_PORT_GEN_MASTER;
 237		rio_write_config_32(rdev,
 238				    rdev->phys_efptr + RIO_PORT_GEN_CTL_CSR,
 239				    result);
 240	}
 241
 242	return ret;
 243}
 244
 245/**
 246 * rio_enum_host- Set host lock and initialize host destination ID
 247 * @port: Master port to issue transaction
 248 *
 249 * Sets the local host master port lock and destination ID register
 250 * with the host device ID value. The host device ID value is provided
 251 * by the platform. Returns %0 on success or %-1 on failure.
 252 */
 253static int rio_enum_host(struct rio_mport *port)
 254{
 255	u32 result;
 256
 257	/* Set master port host device id lock */
 258	rio_local_write_config_32(port, RIO_HOST_DID_LOCK_CSR,
 259				  port->host_deviceid);
 260
 261	rio_local_read_config_32(port, RIO_HOST_DID_LOCK_CSR, &result);
 262	if ((result & 0xffff) != port->host_deviceid)
 263		return -1;
 264
 265	/* Set master port destid and init destid ctr */
 266	rio_local_set_device_id(port, port->host_deviceid);
 267	return 0;
 268}
 269
 270/**
 271 * rio_device_has_destid- Test if a device contains a destination ID register
 272 * @port: Master port to issue transaction
 273 * @src_ops: RIO device source operations
 274 * @dst_ops: RIO device destination operations
 275 *
 276 * Checks the provided @src_ops and @dst_ops for the necessary transaction
 277 * capabilities that indicate whether or not a device will implement a
 278 * destination ID register. Returns 1 if true or 0 if false.
 279 */
 280static int rio_device_has_destid(struct rio_mport *port, int src_ops,
 281				 int dst_ops)
 282{
 283	u32 mask = RIO_OPS_READ | RIO_OPS_WRITE | RIO_OPS_ATOMIC_TST_SWP | RIO_OPS_ATOMIC_INC | RIO_OPS_ATOMIC_DEC | RIO_OPS_ATOMIC_SET | RIO_OPS_ATOMIC_CLR;
 284
 285	return !!((src_ops | dst_ops) & mask);
 286}
 287
 288/**
 289 * rio_release_dev- Frees a RIO device struct
 290 * @dev: LDM device associated with a RIO device struct
 291 *
 292 * Gets the RIO device struct associated a RIO device struct.
 293 * The RIO device struct is freed.
 294 */
 295static void rio_release_dev(struct device *dev)
 296{
 297	struct rio_dev *rdev;
 298
 299	rdev = to_rio_dev(dev);
 300	kfree(rdev);
 301}
 302
 303/**
 304 * rio_is_switch- Tests if a RIO device has switch capabilities
 305 * @rdev: RIO device
 306 *
 307 * Gets the RIO device Processing Element Features register
 308 * contents and tests for switch capabilities. Returns 1 if
 309 * the device is a switch or 0 if it is not a switch.
 310 * The RIO device struct is freed.
 311 */
 312static int rio_is_switch(struct rio_dev *rdev)
 313{
 314	if (rdev->pef & RIO_PEF_SWITCH)
 315		return 1;
 316	return 0;
 317}
 318
 319/**
 320 * rio_setup_device- Allocates and sets up a RIO device
 321 * @net: RIO network
 322 * @port: Master port to send transactions
 323 * @destid: Current destination ID
 324 * @hopcount: Current hopcount
 325 * @do_enum: Enumeration/Discovery mode flag
 326 *
 327 * Allocates a RIO device and configures fields based on configuration
 328 * space contents. If device has a destination ID register, a destination
 329 * ID is either assigned in enumeration mode or read from configuration
 330 * space in discovery mode.  If the device has switch capabilities, then
 331 * a switch is allocated and configured appropriately. Returns a pointer
 332 * to a RIO device on success or NULL on failure.
 333 *
 334 */
 335static struct rio_dev *rio_setup_device(struct rio_net *net,
 336					struct rio_mport *port, u16 destid,
 337					u8 hopcount, int do_enum)
 338{
 339	int ret = 0;
 340	struct rio_dev *rdev;
 341	struct rio_switch *rswitch = NULL;
 342	int result, rdid;
 343	size_t size;
 344	u32 swpinfo = 0;
 345
 346	size = sizeof(struct rio_dev);
 347	if (rio_mport_read_config_32(port, destid, hopcount,
 348				     RIO_PEF_CAR, &result))
 349		return NULL;
 350
 351	if (result & (RIO_PEF_SWITCH | RIO_PEF_MULTIPORT)) {
 352		rio_mport_read_config_32(port, destid, hopcount,
 353					 RIO_SWP_INFO_CAR, &swpinfo);
 354		if (result & RIO_PEF_SWITCH) {
 355			size += (RIO_GET_TOTAL_PORTS(swpinfo) *
 356				sizeof(rswitch->nextdev[0])) + sizeof(*rswitch);
 357		}
 358	}
 359
 360	rdev = kzalloc(size, GFP_KERNEL);
 361	if (!rdev)
 362		return NULL;
 363
 364	rdev->net = net;
 365	rdev->pef = result;
 366	rdev->swpinfo = swpinfo;
 367	rio_mport_read_config_32(port, destid, hopcount, RIO_DEV_ID_CAR,
 368				 &result);
 369	rdev->did = result >> 16;
 370	rdev->vid = result & 0xffff;
 371	rio_mport_read_config_32(port, destid, hopcount, RIO_DEV_INFO_CAR,
 372				 &rdev->device_rev);
 373	rio_mport_read_config_32(port, destid, hopcount, RIO_ASM_ID_CAR,
 374				 &result);
 375	rdev->asm_did = result >> 16;
 376	rdev->asm_vid = result & 0xffff;
 377	rio_mport_read_config_32(port, destid, hopcount, RIO_ASM_INFO_CAR,
 378				 &result);
 379	rdev->asm_rev = result >> 16;
 380	if (rdev->pef & RIO_PEF_EXT_FEATURES) {
 381		rdev->efptr = result & 0xffff;
 382		rdev->phys_efptr = rio_mport_get_physefb(port, 0, destid,
 383							 hopcount);
 384
 385		rdev->em_efptr = rio_mport_get_feature(port, 0, destid,
 386						hopcount, RIO_EFB_ERR_MGMNT);
 387	}
 388
 389	rio_mport_read_config_32(port, destid, hopcount, RIO_SRC_OPS_CAR,
 390				 &rdev->src_ops);
 391	rio_mport_read_config_32(port, destid, hopcount, RIO_DST_OPS_CAR,
 392				 &rdev->dst_ops);
 393
 394	if (do_enum) {
 395		/* Assign component tag to device */
 396		if (next_comptag >= 0x10000) {
 397			pr_err("RIO: Component Tag Counter Overflow\n");
 398			goto cleanup;
 399		}
 400		rio_mport_write_config_32(port, destid, hopcount,
 401					  RIO_COMPONENT_TAG_CSR, next_comptag);
 402		rdev->comp_tag = next_comptag++;
 403		rdev->do_enum = true;
 404	}  else {
 405		rio_mport_read_config_32(port, destid, hopcount,
 406					 RIO_COMPONENT_TAG_CSR,
 407					 &rdev->comp_tag);
 408	}
 409
 410	if (rio_device_has_destid(port, rdev->src_ops, rdev->dst_ops)) {
 411		if (do_enum) {
 412			rio_set_device_id(port, destid, hopcount, next_destid);
 413			rdev->destid = next_destid;
 414			next_destid = rio_destid_alloc(net);
 415		} else
 416			rdev->destid = rio_get_device_id(port, destid, hopcount);
 417
 418		rdev->hopcount = 0xff;
 419	} else {
 420		/* Switch device has an associated destID which
 421		 * will be adjusted later
 422		 */
 423		rdev->destid = destid;
 424		rdev->hopcount = hopcount;
 425	}
 426
 427	/* If a PE has both switch and other functions, show it as a switch */
 428	if (rio_is_switch(rdev)) {
 429		rswitch = rdev->rswitch;
 430		rswitch->port_ok = 0;
 431		spin_lock_init(&rswitch->lock);
 432		rswitch->route_table = kzalloc(sizeof(u8)*
 433					RIO_MAX_ROUTE_ENTRIES(port->sys_size),
 434					GFP_KERNEL);
 435		if (!rswitch->route_table)
 436			goto cleanup;
 437		/* Initialize switch route table */
 438		for (rdid = 0; rdid < RIO_MAX_ROUTE_ENTRIES(port->sys_size);
 439				rdid++)
 440			rswitch->route_table[rdid] = RIO_INVALID_ROUTE;
 441		dev_set_name(&rdev->dev, "%02x:s:%04x", rdev->net->id,
 442			     rdev->comp_tag & RIO_CTAG_UDEVID);
 443
 444		if (do_enum)
 445			rio_route_clr_table(rdev, RIO_GLOBAL_TABLE, 0);
 446	} else {
 447		if (do_enum)
 448			/*Enable Input Output Port (transmitter reviever)*/
 449			rio_enable_rx_tx_port(port, 0, destid, hopcount, 0);
 450
 451		dev_set_name(&rdev->dev, "%02x:e:%04x", rdev->net->id,
 452			     rdev->comp_tag & RIO_CTAG_UDEVID);
 453	}
 454
 455	rdev->dev.parent = &net->dev;
 456	rio_attach_device(rdev);
 457	rdev->dev.release = rio_release_dev;
 458	rdev->dma_mask = DMA_BIT_MASK(32);
 459	rdev->dev.dma_mask = &rdev->dma_mask;
 460	rdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 461
 462	if (rdev->dst_ops & RIO_DST_OPS_DOORBELL)
 463		rio_init_dbell_res(&rdev->riores[RIO_DOORBELL_RESOURCE],
 464				   0, 0xffff);
 465
 466	ret = rio_add_device(rdev);
 467	if (ret)
 468		goto cleanup;
 469
 470	rio_dev_get(rdev);
 471
 472	return rdev;
 473
 474cleanup:
 475	if (rswitch)
 476		kfree(rswitch->route_table);
 477
 478	kfree(rdev);
 479	return NULL;
 480}
 481
 482/**
 483 * rio_sport_is_active- Tests if a switch port has an active connection.
 484 * @port: Master port to send transaction
 485 * @destid: Associated destination ID for switch
 486 * @hopcount: Hopcount to reach switch
 487 * @sport: Switch port number
 488 *
 489 * Reads the port error status CSR for a particular switch port to
 490 * determine if the port has an active link.  Returns
 491 * %RIO_PORT_N_ERR_STS_PORT_OK if the port is active or %0 if it is
 492 * inactive.
 493 */
 494static int
 495rio_sport_is_active(struct rio_mport *port, u16 destid, u8 hopcount, int sport)
 496{
 497	u32 result = 0;
 498	u32 ext_ftr_ptr;
 499
 500	ext_ftr_ptr = rio_mport_get_efb(port, 0, destid, hopcount, 0);
 501
 502	while (ext_ftr_ptr) {
 503		rio_mport_read_config_32(port, destid, hopcount,
 504					 ext_ftr_ptr, &result);
 505		result = RIO_GET_BLOCK_ID(result);
 506		if ((result == RIO_EFB_SER_EP_FREE_ID) ||
 507		    (result == RIO_EFB_SER_EP_FREE_ID_V13P) ||
 508		    (result == RIO_EFB_SER_EP_FREC_ID))
 509			break;
 510
 511		ext_ftr_ptr = rio_mport_get_efb(port, 0, destid, hopcount,
 512						ext_ftr_ptr);
 513	}
 514
 515	if (ext_ftr_ptr)
 516		rio_mport_read_config_32(port, destid, hopcount,
 517					 ext_ftr_ptr +
 518					 RIO_PORT_N_ERR_STS_CSR(sport),
 519					 &result);
 520
 521	return result & RIO_PORT_N_ERR_STS_PORT_OK;
 522}
 523
 524/**
 525 * rio_get_host_deviceid_lock- Reads the Host Device ID Lock CSR on a device
 526 * @port: Master port to send transaction
 527 * @hopcount: Number of hops to the device
 528 *
 529 * Used during enumeration to read the Host Device ID Lock CSR on a
 530 * RIO device. Returns the value of the lock register.
 531 */
 532static u16 rio_get_host_deviceid_lock(struct rio_mport *port, u8 hopcount)
 533{
 534	u32 result;
 535
 536	rio_mport_read_config_32(port, RIO_ANY_DESTID(port->sys_size), hopcount,
 537				 RIO_HOST_DID_LOCK_CSR, &result);
 538
 539	return (u16) (result & 0xffff);
 540}
 541
 542/**
 543 * rio_enum_peer- Recursively enumerate a RIO network through a master port
 544 * @net: RIO network being enumerated
 545 * @port: Master port to send transactions
 546 * @hopcount: Number of hops into the network
 547 * @prev: Previous RIO device connected to the enumerated one
 548 * @prev_port: Port on previous RIO device
 549 *
 550 * Recursively enumerates a RIO network.  Transactions are sent via the
 551 * master port passed in @port.
 552 */
 553static int rio_enum_peer(struct rio_net *net, struct rio_mport *port,
 554			 u8 hopcount, struct rio_dev *prev, int prev_port)
 555{
 556	struct rio_dev *rdev;
 557	u32 regval;
 558	int tmp;
 559
 560	if (rio_mport_chk_dev_access(port,
 561			RIO_ANY_DESTID(port->sys_size), hopcount)) {
 562		pr_debug("RIO: device access check failed\n");
 563		return -1;
 564	}
 565
 566	if (rio_get_host_deviceid_lock(port, hopcount) == port->host_deviceid) {
 567		pr_debug("RIO: PE already discovered by this host\n");
 568		/*
 569		 * Already discovered by this host. Add it as another
 570		 * link to the existing device.
 571		 */
 572		rio_mport_read_config_32(port, RIO_ANY_DESTID(port->sys_size),
 573				hopcount, RIO_COMPONENT_TAG_CSR, &regval);
 574
 575		if (regval) {
 576			rdev = rio_get_comptag((regval & 0xffff), NULL);
 577
 578			if (rdev && prev && rio_is_switch(prev)) {
 579				pr_debug("RIO: redundant path to %s\n",
 580					 rio_name(rdev));
 581				prev->rswitch->nextdev[prev_port] = rdev;
 582			}
 583		}
 584
 585		return 0;
 586	}
 587
 588	/* Attempt to acquire device lock */
 589	rio_mport_write_config_32(port, RIO_ANY_DESTID(port->sys_size),
 590				  hopcount,
 591				  RIO_HOST_DID_LOCK_CSR, port->host_deviceid);
 592	while ((tmp = rio_get_host_deviceid_lock(port, hopcount))
 593	       < port->host_deviceid) {
 594		/* Delay a bit */
 595		mdelay(1);
 596		/* Attempt to acquire device lock again */
 597		rio_mport_write_config_32(port, RIO_ANY_DESTID(port->sys_size),
 598					  hopcount,
 599					  RIO_HOST_DID_LOCK_CSR,
 600					  port->host_deviceid);
 601	}
 602
 603	if (rio_get_host_deviceid_lock(port, hopcount) > port->host_deviceid) {
 604		pr_debug(
 605		    "RIO: PE locked by a higher priority host...retreating\n");
 606		return -1;
 607	}
 608
 609	/* Setup new RIO device */
 610	rdev = rio_setup_device(net, port, RIO_ANY_DESTID(port->sys_size),
 611					hopcount, 1);
 612	if (rdev) {
 613		rdev->prev = prev;
 614		if (prev && rio_is_switch(prev))
 615			prev->rswitch->nextdev[prev_port] = rdev;
 616	} else
 617		return -1;
 618
 619	if (rio_is_switch(rdev)) {
 620		int sw_destid;
 621		int cur_destid;
 622		int sw_inport;
 623		u16 destid;
 624		int port_num;
 625
 626		sw_inport = RIO_GET_PORT_NUM(rdev->swpinfo);
 627		rio_route_add_entry(rdev, RIO_GLOBAL_TABLE,
 628				    port->host_deviceid, sw_inport, 0);
 629		rdev->rswitch->route_table[port->host_deviceid] = sw_inport;
 630
 631		destid = rio_destid_first(net);
 632		while (destid != RIO_INVALID_DESTID && destid < next_destid) {
 633			if (destid != port->host_deviceid) {
 634				rio_route_add_entry(rdev, RIO_GLOBAL_TABLE,
 635						    destid, sw_inport, 0);
 636				rdev->rswitch->route_table[destid] = sw_inport;
 637			}
 638			destid = rio_destid_next(net, destid + 1);
 639		}
 640		pr_debug(
 641		    "RIO: found %s (vid %4.4x did %4.4x) with %d ports\n",
 642		    rio_name(rdev), rdev->vid, rdev->did,
 643		    RIO_GET_TOTAL_PORTS(rdev->swpinfo));
 644		sw_destid = next_destid;
 645		for (port_num = 0;
 646		     port_num < RIO_GET_TOTAL_PORTS(rdev->swpinfo);
 647		     port_num++) {
 648			if (sw_inport == port_num) {
 649				rio_enable_rx_tx_port(port, 0,
 650					      RIO_ANY_DESTID(port->sys_size),
 651					      hopcount, port_num);
 652				rdev->rswitch->port_ok |= (1 << port_num);
 653				continue;
 654			}
 655
 656			cur_destid = next_destid;
 657
 658			if (rio_sport_is_active
 659			    (port, RIO_ANY_DESTID(port->sys_size), hopcount,
 660			     port_num)) {
 661				pr_debug(
 662				    "RIO: scanning device on port %d\n",
 663				    port_num);
 664				rio_enable_rx_tx_port(port, 0,
 665					      RIO_ANY_DESTID(port->sys_size),
 666					      hopcount, port_num);
 667				rdev->rswitch->port_ok |= (1 << port_num);
 668				rio_route_add_entry(rdev, RIO_GLOBAL_TABLE,
 669						RIO_ANY_DESTID(port->sys_size),
 670						port_num, 0);
 671
 672				if (rio_enum_peer(net, port, hopcount + 1,
 673						  rdev, port_num) < 0)
 674					return -1;
 675
 676				/* Update routing tables */
 677				destid = rio_destid_next(net, cur_destid + 1);
 678				if (destid != RIO_INVALID_DESTID) {
 679					for (destid = cur_destid;
 680					     destid < next_destid;) {
 681						if (destid != port->host_deviceid) {
 682							rio_route_add_entry(rdev,
 683								    RIO_GLOBAL_TABLE,
 684								    destid,
 685								    port_num,
 686								    0);
 687							rdev->rswitch->
 688								route_table[destid] =
 689								port_num;
 690						}
 691						destid = rio_destid_next(net,
 692								destid + 1);
 693					}
 694				}
 695			} else {
 696				/* If switch supports Error Management,
 697				 * set PORT_LOCKOUT bit for unused port
 698				 */
 699				if (rdev->em_efptr)
 700					rio_set_port_lockout(rdev, port_num, 1);
 701
 702				rdev->rswitch->port_ok &= ~(1 << port_num);
 703			}
 704		}
 705
 706		/* Direct Port-write messages to the enumeratiing host */
 707		if ((rdev->src_ops & RIO_SRC_OPS_PORT_WRITE) &&
 708		    (rdev->em_efptr)) {
 709			rio_write_config_32(rdev,
 710					rdev->em_efptr + RIO_EM_PW_TGT_DEVID,
 711					(port->host_deviceid << 16) |
 712					(port->sys_size << 15));
 713		}
 714
 715		rio_init_em(rdev);
 716
 717		/* Check for empty switch */
 718		if (next_destid == sw_destid)
 719			next_destid = rio_destid_alloc(net);
 720
 721		rdev->destid = sw_destid;
 722	} else
 723		pr_debug("RIO: found %s (vid %4.4x did %4.4x)\n",
 724		    rio_name(rdev), rdev->vid, rdev->did);
 725
 726	return 0;
 727}
 728
 729/**
 730 * rio_enum_complete- Tests if enumeration of a network is complete
 731 * @port: Master port to send transaction
 732 *
 733 * Tests the PGCCSR discovered bit for non-zero value (enumeration
 734 * complete flag). Return %1 if enumeration is complete or %0 if
 735 * enumeration is incomplete.
 736 */
 737static int rio_enum_complete(struct rio_mport *port)
 738{
 739	u32 regval;
 740
 741	rio_local_read_config_32(port, port->phys_efptr + RIO_PORT_GEN_CTL_CSR,
 742				 &regval);
 743	return (regval & RIO_PORT_GEN_DISCOVERED) ? 1 : 0;
 744}
 745
 746/**
 747 * rio_disc_peer- Recursively discovers a RIO network through a master port
 748 * @net: RIO network being discovered
 749 * @port: Master port to send transactions
 750 * @destid: Current destination ID in network
 751 * @hopcount: Number of hops into the network
 752 * @prev: previous rio_dev
 753 * @prev_port: previous port number
 754 *
 755 * Recursively discovers a RIO network.  Transactions are sent via the
 756 * master port passed in @port.
 757 */
 758static int
 759rio_disc_peer(struct rio_net *net, struct rio_mport *port, u16 destid,
 760	      u8 hopcount, struct rio_dev *prev, int prev_port)
 761{
 762	u8 port_num, route_port;
 763	struct rio_dev *rdev;
 764	u16 ndestid;
 765
 766	/* Setup new RIO device */
 767	if ((rdev = rio_setup_device(net, port, destid, hopcount, 0))) {
 768		rdev->prev = prev;
 769		if (prev && rio_is_switch(prev))
 770			prev->rswitch->nextdev[prev_port] = rdev;
 771	} else
 772		return -1;
 773
 774	if (rio_is_switch(rdev)) {
 775		/* Associated destid is how we accessed this switch */
 776		rdev->destid = destid;
 777
 778		pr_debug(
 779		    "RIO: found %s (vid %4.4x did %4.4x) with %d ports\n",
 780		    rio_name(rdev), rdev->vid, rdev->did,
 781		    RIO_GET_TOTAL_PORTS(rdev->swpinfo));
 782		for (port_num = 0;
 783		     port_num < RIO_GET_TOTAL_PORTS(rdev->swpinfo);
 784		     port_num++) {
 785			if (RIO_GET_PORT_NUM(rdev->swpinfo) == port_num)
 786				continue;
 787
 788			if (rio_sport_is_active
 789			    (port, destid, hopcount, port_num)) {
 790				pr_debug(
 791				    "RIO: scanning device on port %d\n",
 792				    port_num);
 793
 794				rio_lock_device(port, destid, hopcount, 1000);
 795
 796				for (ndestid = 0;
 797				     ndestid < RIO_ANY_DESTID(port->sys_size);
 798				     ndestid++) {
 799					rio_route_get_entry(rdev,
 800							    RIO_GLOBAL_TABLE,
 801							    ndestid,
 802							    &route_port, 0);
 803					if (route_port == port_num)
 804						break;
 805				}
 806
 807				if (ndestid == RIO_ANY_DESTID(port->sys_size))
 808					continue;
 809				rio_unlock_device(port, destid, hopcount);
 810				if (rio_disc_peer(net, port, ndestid,
 811					hopcount + 1, rdev, port_num) < 0)
 812					return -1;
 813			}
 814		}
 815	} else
 816		pr_debug("RIO: found %s (vid %4.4x did %4.4x)\n",
 817		    rio_name(rdev), rdev->vid, rdev->did);
 818
 819	return 0;
 820}
 821
 822/**
 823 * rio_mport_is_active- Tests if master port link is active
 824 * @port: Master port to test
 825 *
 826 * Reads the port error status CSR for the master port to
 827 * determine if the port has an active link.  Returns
 828 * %RIO_PORT_N_ERR_STS_PORT_OK if the  master port is active
 829 * or %0 if it is inactive.
 830 */
 831static int rio_mport_is_active(struct rio_mport *port)
 832{
 833	u32 result = 0;
 834	u32 ext_ftr_ptr;
 835	int *entry = rio_mport_phys_table;
 836
 837	do {
 838		if ((ext_ftr_ptr =
 839		     rio_mport_get_feature(port, 1, 0, 0, *entry)))
 840			break;
 841	} while (*++entry >= 0);
 842
 843	if (ext_ftr_ptr)
 844		rio_local_read_config_32(port,
 845					 ext_ftr_ptr +
 846					 RIO_PORT_N_ERR_STS_CSR(port->index),
 847					 &result);
 848
 849	return result & RIO_PORT_N_ERR_STS_PORT_OK;
 850}
 851
 852static void rio_scan_release_net(struct rio_net *net)
 853{
 854	pr_debug("RIO-SCAN: %s: net_%d\n", __func__, net->id);
 855	kfree(net->enum_data);
 856}
 857
 858static void rio_scan_release_dev(struct device *dev)
 859{
 860	struct rio_net *net;
 861
 862	net = to_rio_net(dev);
 863	pr_debug("RIO-SCAN: %s: net_%d\n", __func__, net->id);
 864	kfree(net);
 865}
 866
 867/*
 868 * rio_scan_alloc_net - Allocate and configure a new RIO network
 869 * @mport: Master port associated with the RIO network
 870 * @do_enum: Enumeration/Discovery mode flag
 871 * @start: logical minimal start id for new net
 872 *
 873 * Allocates a new RIO network structure and initializes enumerator-specific
 874 * part of it (if required).
 875 * Returns a RIO network pointer on success or %NULL on failure.
 876 */
 877static struct rio_net *rio_scan_alloc_net(struct rio_mport *mport,
 878					  int do_enum, u16 start)
 879{
 880	struct rio_net *net;
 881
 882	net = rio_alloc_net(mport);
 883
 884	if (net && do_enum) {
 885		struct rio_id_table *idtab;
 886		size_t size;
 887
 888		size = sizeof(struct rio_id_table) +
 889				BITS_TO_LONGS(
 890					RIO_MAX_ROUTE_ENTRIES(mport->sys_size)
 891					) * sizeof(long);
 892
 893		idtab = kzalloc(size, GFP_KERNEL);
 894
 895		if (idtab == NULL) {
 896			pr_err("RIO: failed to allocate destID table\n");
 897			rio_free_net(net);
 898			net = NULL;
 899		} else {
 900			net->enum_data = idtab;
 901			net->release = rio_scan_release_net;
 902			idtab->start = start;
 903			idtab->max = RIO_MAX_ROUTE_ENTRIES(mport->sys_size);
 904			spin_lock_init(&idtab->lock);
 905		}
 906	}
 907
 908	if (net) {
 909		net->id = mport->id;
 910		net->hport = mport;
 911		dev_set_name(&net->dev, "rnet_%d", net->id);
 912		net->dev.parent = &mport->dev;
 913		net->dev.release = rio_scan_release_dev;
 914		rio_add_net(net);
 915	}
 916
 917	return net;
 918}
 919
 920/**
 921 * rio_update_route_tables- Updates route tables in switches
 922 * @net: RIO network to run update on
 923 *
 924 * For each enumerated device, ensure that each switch in a system
 925 * has correct routing entries. Add routes for devices that where
 926 * unknown dirung the first enumeration pass through the switch.
 927 */
 928static void rio_update_route_tables(struct rio_net *net)
 929{
 930	struct rio_dev *rdev, *swrdev;
 931	struct rio_switch *rswitch;
 932	u8 sport;
 933	u16 destid;
 934
 935	list_for_each_entry(rdev, &net->devices, net_list) {
 936
 937		destid = rdev->destid;
 938
 939		list_for_each_entry(rswitch, &net->switches, node) {
 940
 941			if (rio_is_switch(rdev)	&& (rdev->rswitch == rswitch))
 942				continue;
 943
 944			if (RIO_INVALID_ROUTE == rswitch->route_table[destid]) {
 945				swrdev = sw_to_rio_dev(rswitch);
 946
 947				/* Skip if destid ends in empty switch*/
 948				if (swrdev->destid == destid)
 949					continue;
 950
 951				sport = RIO_GET_PORT_NUM(swrdev->swpinfo);
 952
 953				rio_route_add_entry(swrdev, RIO_GLOBAL_TABLE,
 954						    destid, sport, 0);
 955				rswitch->route_table[destid] = sport;
 956			}
 957		}
 958	}
 959}
 960
 961/**
 962 * rio_init_em - Initializes RIO Error Management (for switches)
 963 * @rdev: RIO device
 964 *
 965 * For each enumerated switch, call device-specific error management
 966 * initialization routine (if supplied by the switch driver).
 967 */
 968static void rio_init_em(struct rio_dev *rdev)
 969{
 970	if (rio_is_switch(rdev) && (rdev->em_efptr) &&
 971	    rdev->rswitch->ops && rdev->rswitch->ops->em_init) {
 972		rdev->rswitch->ops->em_init(rdev);
 973	}
 974}
 975
 976/**
 977 * rio_enum_mport- Start enumeration through a master port
 978 * @mport: Master port to send transactions
 979 * @flags: Enumeration control flags
 980 *
 981 * Starts the enumeration process. If somebody has enumerated our
 982 * master port device, then give up. If not and we have an active
 983 * link, then start recursive peer enumeration. Returns %0 if
 984 * enumeration succeeds or %-EBUSY if enumeration fails.
 985 */
 986static int rio_enum_mport(struct rio_mport *mport, u32 flags)
 987{
 988	struct rio_net *net = NULL;
 989	int rc = 0;
 990
 991	printk(KERN_INFO "RIO: enumerate master port %d, %s\n", mport->id,
 992	       mport->name);
 993
 994	/*
 995	 * To avoid multiple start requests (repeat enumeration is not supported
 996	 * by this method) check if enumeration/discovery was performed for this
 997	 * mport: if mport was added into the list of mports for a net exit
 998	 * with error.
 999	 */
1000	if (mport->nnode.next || mport->nnode.prev)
1001		return -EBUSY;
1002
1003	/* If somebody else enumerated our master port device, bail. */
1004	if (rio_enum_host(mport) < 0) {
1005		printk(KERN_INFO
1006		       "RIO: master port %d device has been enumerated by a remote host\n",
1007		       mport->id);
1008		rc = -EBUSY;
1009		goto out;
1010	}
1011
1012	/* If master port has an active link, allocate net and enum peers */
1013	if (rio_mport_is_active(mport)) {
1014		net = rio_scan_alloc_net(mport, 1, 0);
1015		if (!net) {
1016			printk(KERN_ERR "RIO: failed to allocate new net\n");
1017			rc = -ENOMEM;
1018			goto out;
1019		}
1020
1021		/* reserve mport destID in new net */
1022		rio_destid_reserve(net, mport->host_deviceid);
1023
1024		/* Enable Input Output Port (transmitter reviever) */
1025		rio_enable_rx_tx_port(mport, 1, 0, 0, 0);
1026
1027		/* Set component tag for host */
1028		rio_local_write_config_32(mport, RIO_COMPONENT_TAG_CSR,
1029					  next_comptag++);
1030
1031		next_destid = rio_destid_alloc(net);
1032
1033		if (rio_enum_peer(net, mport, 0, NULL, 0) < 0) {
1034			/* A higher priority host won enumeration, bail. */
1035			printk(KERN_INFO
1036			       "RIO: master port %d device has lost enumeration to a remote host\n",
1037			       mport->id);
1038			rio_clear_locks(net);
1039			rc = -EBUSY;
1040			goto out;
1041		}
1042		/* free the last allocated destID (unused) */
1043		rio_destid_free(net, next_destid);
1044		rio_update_route_tables(net);
1045		rio_clear_locks(net);
1046		rio_pw_enable(mport, 1);
1047	} else {
1048		printk(KERN_INFO "RIO: master port %d link inactive\n",
1049		       mport->id);
1050		rc = -EINVAL;
1051	}
1052
1053      out:
1054	return rc;
1055}
1056
1057/**
1058 * rio_build_route_tables- Generate route tables from switch route entries
1059 * @net: RIO network to run route tables scan on
1060 *
1061 * For each switch device, generate a route table by copying existing
1062 * route entries from the switch.
1063 */
1064static void rio_build_route_tables(struct rio_net *net)
1065{
1066	struct rio_switch *rswitch;
1067	struct rio_dev *rdev;
1068	int i;
1069	u8 sport;
1070
1071	list_for_each_entry(rswitch, &net->switches, node) {
1072		rdev = sw_to_rio_dev(rswitch);
1073
1074		rio_lock_device(net->hport, rdev->destid,
1075				rdev->hopcount, 1000);
1076		for (i = 0;
1077		     i < RIO_MAX_ROUTE_ENTRIES(net->hport->sys_size);
1078		     i++) {
1079			if (rio_route_get_entry(rdev, RIO_GLOBAL_TABLE,
1080						i, &sport, 0) < 0)
1081				continue;
1082			rswitch->route_table[i] = sport;
1083		}
1084
1085		rio_unlock_device(net->hport, rdev->destid, rdev->hopcount);
1086	}
1087}
1088
1089/**
1090 * rio_disc_mport- Start discovery through a master port
1091 * @mport: Master port to send transactions
1092 * @flags: discovery control flags
1093 *
1094 * Starts the discovery process. If we have an active link,
1095 * then wait for the signal that enumeration is complete (if wait
1096 * is allowed).
1097 * When enumeration completion is signaled, start recursive
1098 * peer discovery. Returns %0 if discovery succeeds or %-EBUSY
1099 * on failure.
1100 */
1101static int rio_disc_mport(struct rio_mport *mport, u32 flags)
1102{
1103	struct rio_net *net = NULL;
1104	unsigned long to_end;
1105
1106	printk(KERN_INFO "RIO: discover master port %d, %s\n", mport->id,
1107	       mport->name);
1108
1109	/* If master port has an active link, allocate net and discover peers */
1110	if (rio_mport_is_active(mport)) {
1111		if (rio_enum_complete(mport))
1112			goto enum_done;
1113		else if (flags & RIO_SCAN_ENUM_NO_WAIT)
1114			return -EAGAIN;
1115
1116		pr_debug("RIO: wait for enumeration to complete...\n");
1117
1118		to_end = jiffies + CONFIG_RAPIDIO_DISC_TIMEOUT * HZ;
1119		while (time_before(jiffies, to_end)) {
1120			if (rio_enum_complete(mport))
1121				goto enum_done;
1122			msleep(10);
1123		}
1124
1125		pr_debug("RIO: discovery timeout on mport %d %s\n",
1126			 mport->id, mport->name);
1127		goto bail;
1128enum_done:
1129		pr_debug("RIO: ... enumeration done\n");
1130
1131		net = rio_scan_alloc_net(mport, 0, 0);
1132		if (!net) {
1133			printk(KERN_ERR "RIO: Failed to allocate new net\n");
1134			goto bail;
1135		}
1136
1137		/* Read DestID assigned by enumerator */
1138		rio_local_read_config_32(mport, RIO_DID_CSR,
1139					 &mport->host_deviceid);
1140		mport->host_deviceid = RIO_GET_DID(mport->sys_size,
1141						   mport->host_deviceid);
1142
1143		if (rio_disc_peer(net, mport, RIO_ANY_DESTID(mport->sys_size),
1144					0, NULL, 0) < 0) {
1145			printk(KERN_INFO
1146			       "RIO: master port %d device has failed discovery\n",
1147			       mport->id);
1148			goto bail;
1149		}
1150
1151		rio_build_route_tables(net);
1152	}
1153
1154	return 0;
1155bail:
1156	return -EBUSY;
1157}
1158
1159static struct rio_scan rio_scan_ops = {
1160	.owner = THIS_MODULE,
1161	.enumerate = rio_enum_mport,
1162	.discover = rio_disc_mport,
1163};
1164
1165static bool scan;
1166module_param(scan, bool, 0);
1167MODULE_PARM_DESC(scan, "Start RapidIO network enumeration/discovery "
1168			"(default = 0)");
1169
1170/**
1171 * rio_basic_attach:
1172 *
1173 * When this enumeration/discovery method is loaded as a module this function
1174 * registers its specific enumeration and discover routines for all available
1175 * RapidIO mport devices. The "scan" command line parameter controls ability of
1176 * the module to start RapidIO enumeration/discovery automatically.
1177 *
1178 * Returns 0 for success or -EIO if unable to register itself.
1179 *
1180 * This enumeration/discovery method cannot be unloaded and therefore does not
1181 * provide a matching cleanup_module routine.
1182 */
1183
1184static int __init rio_basic_attach(void)
1185{
1186	if (rio_register_scan(RIO_MPORT_ANY, &rio_scan_ops))
1187		return -EIO;
1188	if (scan)
1189		rio_init_mports();
1190	return 0;
1191}
1192
1193late_initcall(rio_basic_attach);
1194
1195MODULE_DESCRIPTION("Basic RapidIO enumeration/discovery");
1196MODULE_LICENSE("GPL");