pci.c 11.8 KB
Newer Older
J
Jan Glauber 已提交
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557
/*
 * Copyright IBM Corp. 2012
 *
 * Author(s):
 *   Jan Glauber <jang@linux.vnet.ibm.com>
 *
 * The System z PCI code is a rewrite from a prototype by
 * the following people (Kudoz!):
 *   Alexander Schmidt <alexschm@de.ibm.com>
 *   Christoph Raisch <raisch@de.ibm.com>
 *   Hannes Hering <hering2@de.ibm.com>
 *   Hoang-Nam Nguyen <hnguyen@de.ibm.com>
 *   Jan-Bernd Themann <themann@de.ibm.com>
 *   Stefan Roscher <stefan.roscher@de.ibm.com>
 *   Thomas Klein <tklein@de.ibm.com>
 */

#define COMPONENT "zPCI"
#define pr_fmt(fmt) COMPONENT ": " fmt

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/delay.h>
#include <linux/seq_file.h>
#include <linux/pci.h>
#include <linux/msi.h>

#include <asm/facility.h>
#include <asm/pci_insn.h>

#define DEBUG				/* enable pr_debug */

#define ZPCI_NR_DMA_SPACES		1
#define ZPCI_NR_DEVICES			CONFIG_PCI_NR_FUNCTIONS

/* list of all detected zpci devices */
LIST_HEAD(zpci_list);
DEFINE_MUTEX(zpci_list_lock);

static DECLARE_BITMAP(zpci_domain, ZPCI_NR_DEVICES);
static DEFINE_SPINLOCK(zpci_domain_lock);

/* I/O Map */
static DEFINE_SPINLOCK(zpci_iomap_lock);
static DECLARE_BITMAP(zpci_iomap, ZPCI_IOMAP_MAX_ENTRIES);
struct zpci_iomap_entry *zpci_iomap_start;
EXPORT_SYMBOL_GPL(zpci_iomap_start);

struct zpci_dev *get_zdev(struct pci_dev *pdev)
{
	return (struct zpci_dev *) pdev->sysdata;
}

struct zpci_dev *get_zdev_by_fid(u32 fid)
{
	struct zpci_dev *tmp, *zdev = NULL;

	mutex_lock(&zpci_list_lock);
	list_for_each_entry(tmp, &zpci_list, entry) {
		if (tmp->fid == fid) {
			zdev = tmp;
			break;
		}
	}
	mutex_unlock(&zpci_list_lock);
	return zdev;
}

bool zpci_fid_present(u32 fid)
{
	return (get_zdev_by_fid(fid) != NULL) ? true : false;
}

static struct zpci_dev *get_zdev_by_bus(struct pci_bus *bus)
{
	return (bus && bus->sysdata) ? (struct zpci_dev *) bus->sysdata : NULL;
}

int pci_domain_nr(struct pci_bus *bus)
{
	return ((struct zpci_dev *) bus->sysdata)->domain;
}
EXPORT_SYMBOL_GPL(pci_domain_nr);

int pci_proc_domain(struct pci_bus *bus)
{
	return pci_domain_nr(bus);
}
EXPORT_SYMBOL_GPL(pci_proc_domain);

/* Store PCI function information block */
static int zpci_store_fib(struct zpci_dev *zdev, u8 *fc)
{
	struct zpci_fib *fib;
	u8 status, cc;

	fib = (void *) get_zeroed_page(GFP_KERNEL);
	if (!fib)
		return -ENOMEM;

	do {
		cc = __stpcifc(zdev->fh, 0, fib, &status);
		if (cc == 2) {
			msleep(ZPCI_INSN_BUSY_DELAY);
			memset(fib, 0, PAGE_SIZE);
		}
	} while (cc == 2);

	if (cc)
		pr_err_once("%s: cc: %u  status: %u\n",
			    __func__, cc, status);

	/* Return PCI function controls */
	*fc = fib->fc;

	free_page((unsigned long) fib);
	return (cc) ? -EIO : 0;
}

#define ZPCI_PCIAS_CFGSPC	15

static int zpci_cfg_load(struct zpci_dev *zdev, int offset, u32 *val, u8 len)
{
	u64 req = ZPCI_CREATE_REQ(zdev->fh, ZPCI_PCIAS_CFGSPC, len);
	u64 data;
	int rc;

	rc = pcilg_instr(&data, req, offset);
	data = data << ((8 - len) * 8);
	data = le64_to_cpu(data);
	if (!rc)
		*val = (u32) data;
	else
		*val = 0xffffffff;
	return rc;
}

static int zpci_cfg_store(struct zpci_dev *zdev, int offset, u32 val, u8 len)
{
	u64 req = ZPCI_CREATE_REQ(zdev->fh, ZPCI_PCIAS_CFGSPC, len);
	u64 data = val;
	int rc;

	data = cpu_to_le64(data);
	data = data >> ((8 - len) * 8);
	rc = pcistg_instr(data, req, offset);
	return rc;
}

void __devinit pcibios_fixup_bus(struct pci_bus *bus)
{
}

resource_size_t pcibios_align_resource(void *data, const struct resource *res,
				       resource_size_t size,
				       resource_size_t align)
{
	return 0;
}

/* Create a virtual mapping cookie for a PCI BAR */
void __iomem *pci_iomap(struct pci_dev *pdev, int bar, unsigned long max)
{
	struct zpci_dev *zdev =	get_zdev(pdev);
	u64 addr;
	int idx;

	if ((bar & 7) != bar)
		return NULL;

	idx = zdev->bars[bar].map_idx;
	spin_lock(&zpci_iomap_lock);
	zpci_iomap_start[idx].fh = zdev->fh;
	zpci_iomap_start[idx].bar = bar;
	spin_unlock(&zpci_iomap_lock);

	addr = ZPCI_IOMAP_ADDR_BASE | ((u64) idx << 48);
	return (void __iomem *) addr;
}
EXPORT_SYMBOL_GPL(pci_iomap);

void pci_iounmap(struct pci_dev *pdev, void __iomem *addr)
{
	unsigned int idx;

	idx = (((__force u64) addr) & ~ZPCI_IOMAP_ADDR_BASE) >> 48;
	spin_lock(&zpci_iomap_lock);
	zpci_iomap_start[idx].fh = 0;
	zpci_iomap_start[idx].bar = 0;
	spin_unlock(&zpci_iomap_lock);
}
EXPORT_SYMBOL_GPL(pci_iounmap);

static int pci_read(struct pci_bus *bus, unsigned int devfn, int where,
		    int size, u32 *val)
{
	struct zpci_dev *zdev = get_zdev_by_bus(bus);

	if (!zdev || devfn != ZPCI_DEVFN)
		return 0;
	return zpci_cfg_load(zdev, where, val, size);
}

static int pci_write(struct pci_bus *bus, unsigned int devfn, int where,
		     int size, u32 val)
{
	struct zpci_dev *zdev = get_zdev_by_bus(bus);

	if (!zdev || devfn != ZPCI_DEVFN)
		return 0;
	return zpci_cfg_store(zdev, where, val, size);
}

static struct pci_ops pci_root_ops = {
	.read = pci_read,
	.write = pci_write,
};

static void zpci_map_resources(struct zpci_dev *zdev)
{
	struct pci_dev *pdev = zdev->pdev;
	resource_size_t len;
	int i;

	for (i = 0; i < PCI_BAR_COUNT; i++) {
		len = pci_resource_len(pdev, i);
		if (!len)
			continue;
		pdev->resource[i].start = (resource_size_t) pci_iomap(pdev, i, 0);
		pdev->resource[i].end = pdev->resource[i].start + len - 1;
		pr_debug("BAR%i: -> start: %Lx  end: %Lx\n",
			i, pdev->resource[i].start, pdev->resource[i].end);
	}
};

static void zpci_unmap_resources(struct pci_dev *pdev)
{
	resource_size_t len;
	int i;

	for (i = 0; i < PCI_BAR_COUNT; i++) {
		len = pci_resource_len(pdev, i);
		if (!len)
			continue;
		pci_iounmap(pdev, (void *) pdev->resource[i].start);
	}
};

struct zpci_dev *zpci_alloc_device(void)
{
	struct zpci_dev *zdev;

	/* Alloc memory for our private pci device data */
	zdev = kzalloc(sizeof(*zdev), GFP_KERNEL);
	if (!zdev)
		return ERR_PTR(-ENOMEM);
	return zdev;
}

void zpci_free_device(struct zpci_dev *zdev)
{
	kfree(zdev);
}

/* Called on removal of pci_dev, leaves zpci and bus device */
static void zpci_remove_device(struct pci_dev *pdev)
{
	struct zpci_dev *zdev = get_zdev(pdev);

	dev_info(&pdev->dev, "Removing device %u\n", zdev->domain);
	zdev->state = ZPCI_FN_STATE_CONFIGURED;
	zpci_unmap_resources(pdev);
	list_del(&zdev->entry);		/* can be called from init */
	zdev->pdev = NULL;
}

static void zpci_scan_devices(void)
{
	struct zpci_dev *zdev;

	mutex_lock(&zpci_list_lock);
	list_for_each_entry(zdev, &zpci_list, entry)
		if (zdev->state == ZPCI_FN_STATE_CONFIGURED)
			zpci_scan_device(zdev);
	mutex_unlock(&zpci_list_lock);
}

/*
 * Too late for any s390 specific setup, since interrupts must be set up
 * already which requires DMA setup too and the pci scan will access the
 * config space, which only works if the function handle is enabled.
 */
int pcibios_enable_device(struct pci_dev *pdev, int mask)
{
	struct resource *res;
	u16 cmd;
	int i;

	pci_read_config_word(pdev, PCI_COMMAND, &cmd);

	for (i = 0; i < PCI_BAR_COUNT; i++) {
		res = &pdev->resource[i];

		if (res->flags & IORESOURCE_IO)
			return -EINVAL;

		if (res->flags & IORESOURCE_MEM)
			cmd |= PCI_COMMAND_MEMORY;
	}
	pci_write_config_word(pdev, PCI_COMMAND, cmd);
	return 0;
}

void pcibios_disable_device(struct pci_dev *pdev)
{
	zpci_remove_device(pdev);
	pdev->sysdata = NULL;
}

static struct resource *zpci_alloc_bus_resource(unsigned long start, unsigned long size,
						unsigned long flags, int domain)
{
	struct resource *r;
	char *name;
	int rc;

	r = kzalloc(sizeof(*r), GFP_KERNEL);
	if (!r)
		return ERR_PTR(-ENOMEM);
	r->start = start;
	r->end = r->start + size - 1;
	r->flags = flags;
	r->parent = &iomem_resource;
	name = kmalloc(18, GFP_KERNEL);
	if (!name) {
		kfree(r);
		return ERR_PTR(-ENOMEM);
	}
	sprintf(name, "PCI Bus: %04x:%02x", domain, ZPCI_BUS_NR);
	r->name = name;

	rc = request_resource(&iomem_resource, r);
	if (rc)
		pr_debug("request resource %pR failed\n", r);
	return r;
}

static int zpci_alloc_iomap(struct zpci_dev *zdev)
{
	int entry;

	spin_lock(&zpci_iomap_lock);
	entry = find_first_zero_bit(zpci_iomap, ZPCI_IOMAP_MAX_ENTRIES);
	if (entry == ZPCI_IOMAP_MAX_ENTRIES) {
		spin_unlock(&zpci_iomap_lock);
		return -ENOSPC;
	}
	set_bit(entry, zpci_iomap);
	spin_unlock(&zpci_iomap_lock);
	return entry;
}

static void zpci_free_iomap(struct zpci_dev *zdev, int entry)
{
	spin_lock(&zpci_iomap_lock);
	memset(&zpci_iomap_start[entry], 0, sizeof(struct zpci_iomap_entry));
	clear_bit(entry, zpci_iomap);
	spin_unlock(&zpci_iomap_lock);
}

static int zpci_create_device_bus(struct zpci_dev *zdev)
{
	struct resource *res;
	LIST_HEAD(resources);
	int i;

	/* allocate mapping entry for each used bar */
	for (i = 0; i < PCI_BAR_COUNT; i++) {
		unsigned long addr, size, flags;
		int entry;

		if (!zdev->bars[i].size)
			continue;
		entry = zpci_alloc_iomap(zdev);
		if (entry < 0)
			return entry;
		zdev->bars[i].map_idx = entry;

		/* only MMIO is supported */
		flags = IORESOURCE_MEM;
		if (zdev->bars[i].val & 8)
			flags |= IORESOURCE_PREFETCH;
		if (zdev->bars[i].val & 4)
			flags |= IORESOURCE_MEM_64;

		addr = ZPCI_IOMAP_ADDR_BASE + ((u64) entry << 48);

		size = 1UL << zdev->bars[i].size;

		res = zpci_alloc_bus_resource(addr, size, flags, zdev->domain);
		if (IS_ERR(res)) {
			zpci_free_iomap(zdev, entry);
			return PTR_ERR(res);
		}
		pci_add_resource(&resources, res);
	}

	zdev->bus = pci_create_root_bus(NULL, ZPCI_BUS_NR, &pci_root_ops,
					zdev, &resources);
	if (!zdev->bus)
		return -EIO;

	zdev->bus->max_bus_speed = zdev->max_bus_speed;
	return 0;
}

static int zpci_alloc_domain(struct zpci_dev *zdev)
{
	spin_lock(&zpci_domain_lock);
	zdev->domain = find_first_zero_bit(zpci_domain, ZPCI_NR_DEVICES);
	if (zdev->domain == ZPCI_NR_DEVICES) {
		spin_unlock(&zpci_domain_lock);
		return -ENOSPC;
	}
	set_bit(zdev->domain, zpci_domain);
	spin_unlock(&zpci_domain_lock);
	return 0;
}

static void zpci_free_domain(struct zpci_dev *zdev)
{
	spin_lock(&zpci_domain_lock);
	clear_bit(zdev->domain, zpci_domain);
	spin_unlock(&zpci_domain_lock);
}

int zpci_create_device(struct zpci_dev *zdev)
{
	int rc;

	rc = zpci_alloc_domain(zdev);
	if (rc)
		goto out;

	rc = zpci_create_device_bus(zdev);
	if (rc)
		goto out_bus;

	mutex_lock(&zpci_list_lock);
	list_add_tail(&zdev->entry, &zpci_list);
	mutex_unlock(&zpci_list_lock);

	if (zdev->state == ZPCI_FN_STATE_STANDBY)
		return 0;

	return 0;

out_bus:
	zpci_free_domain(zdev);
out:
	return rc;
}

void zpci_stop_device(struct zpci_dev *zdev)
{
	/*
	 * Note: SCLP disables fh via set-pci-fn so don't
	 * do that here.
	 */
}
EXPORT_SYMBOL_GPL(zpci_stop_device);

int zpci_scan_device(struct zpci_dev *zdev)
{
	zdev->pdev = pci_scan_single_device(zdev->bus, ZPCI_DEVFN);
	if (!zdev->pdev) {
		pr_err("pci_scan_single_device failed for fid: 0x%x\n",
			zdev->fid);
		goto out;
	}

	zpci_map_resources(zdev);
	pci_bus_add_devices(zdev->bus);

	/* now that pdev was added to the bus mark it as used */
	zdev->state = ZPCI_FN_STATE_ONLINE;
	return 0;

out:
	return -EIO;
}
EXPORT_SYMBOL_GPL(zpci_scan_device);

static inline int barsize(u8 size)
{
	return (size) ? (1 << size) >> 10 : 0;
}

static int zpci_mem_init(void)
{
	/* TODO: use realloc */
	zpci_iomap_start = kzalloc(ZPCI_IOMAP_MAX_ENTRIES * sizeof(*zpci_iomap_start),
				   GFP_KERNEL);
	if (!zpci_iomap_start)
		goto error_zdev;
	return 0;

error_zdev:
	return -ENOMEM;
}

static void zpci_mem_exit(void)
{
	kfree(zpci_iomap_start);
}

unsigned int pci_probe = 1;
EXPORT_SYMBOL_GPL(pci_probe);

char * __init pcibios_setup(char *str)
{
	if (!strcmp(str, "off")) {
		pci_probe = 0;
		return NULL;
	}
	return str;
}

static int __init pci_base_init(void)
{
	int rc;

	if (!pci_probe)
		return 0;

	if (!test_facility(2) || !test_facility(69)
	    || !test_facility(71) || !test_facility(72))
		return 0;

	pr_info("Probing PCI hardware: PCI:%d  SID:%d  AEN:%d\n",
		test_facility(69), test_facility(70),
		test_facility(71));

	rc = zpci_mem_init();
	if (rc)
		goto out_mem;

	zpci_scan_devices();
	return 0;

	zpci_mem_exit();
out_mem:
	return rc;
}
subsys_initcall(pci_base_init);