xref: /rk3399_rockchip-uboot/cmd/pci.c (revision efe4ea7cc24665b65821fc603c505bdffc01c9ef)
1 /*
2  * (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
3  * Andreas Heppel <aheppel@sysgo.de>
4  *
5  * (C) Copyright 2002
6  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
7  * Wolfgang Grandegger, DENX Software Engineering, wg@denx.de.
8  *
9  * SPDX-License-Identifier:	GPL-2.0+
10  */
11 
12 /*
13  * PCI routines
14  */
15 
16 #include <common.h>
17 #include <bootretry.h>
18 #include <cli.h>
19 #include <command.h>
20 #include <console.h>
21 #include <dm.h>
22 #include <asm/processor.h>
23 #include <asm/io.h>
24 #include <pci.h>
25 
26 struct pci_reg_info {
27 	const char *name;
28 	enum pci_size_t size;
29 	u8 offset;
30 };
31 
32 static int pci_byte_size(enum pci_size_t size)
33 {
34 	switch (size) {
35 	case PCI_SIZE_8:
36 		return 1;
37 	case PCI_SIZE_16:
38 		return 2;
39 	case PCI_SIZE_32:
40 	default:
41 		return 4;
42 	}
43 }
44 
45 static int pci_field_width(enum pci_size_t size)
46 {
47 	return pci_byte_size(size) * 2;
48 }
49 
50 static void pci_show_regs(struct udevice *dev, struct pci_reg_info *regs)
51 {
52 	for (; regs->name; regs++) {
53 		unsigned long val;
54 
55 		dm_pci_read_config(dev, regs->offset, &val, regs->size);
56 		printf("  %s =%*s%#.*lx\n", regs->name,
57 		       (int)(28 - strlen(regs->name)), "",
58 		       pci_field_width(regs->size), val);
59 	}
60 }
61 
62 static int pci_bar_show(struct udevice *dev)
63 {
64 	u8 header_type;
65 	int bar_cnt, bar_id, mem_type;
66 	bool is_64, is_io;
67 	u32 base_low, base_high;
68 	u32 size_low, size_high;
69 	u64 base, size;
70 	u32 reg_addr;
71 	int prefetchable;
72 
73 	dm_pci_read_config8(dev, PCI_HEADER_TYPE, &header_type);
74 
75 	if (header_type == PCI_HEADER_TYPE_CARDBUS) {
76 		printf("CardBus doesn't support BARs\n");
77 		return -ENOSYS;
78 	}
79 
80 	bar_cnt = (header_type == PCI_HEADER_TYPE_NORMAL) ? 6 : 2;
81 
82 	printf("ID   Base                Size                Width  Type\n");
83 	printf("----------------------------------------------------------\n");
84 
85 	bar_id = 0;
86 	reg_addr = PCI_BASE_ADDRESS_0;
87 	while (bar_cnt) {
88 		dm_pci_read_config32(dev, reg_addr, &base_low);
89 		dm_pci_write_config32(dev, reg_addr, 0xffffffff);
90 		dm_pci_read_config32(dev, reg_addr, &size_low);
91 		dm_pci_write_config32(dev, reg_addr, base_low);
92 		reg_addr += 4;
93 
94 		base = base_low & ~0xf;
95 		size = size_low & ~0xf;
96 		base_high = 0x0;
97 		size_high = 0xffffffff;
98 		is_64 = 0;
99 		prefetchable = base_low & PCI_BASE_ADDRESS_MEM_PREFETCH;
100 		is_io = base_low & PCI_BASE_ADDRESS_SPACE_IO;
101 		mem_type = base_low & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
102 
103 		if (mem_type == PCI_BASE_ADDRESS_MEM_TYPE_64) {
104 			dm_pci_read_config32(dev, reg_addr, &base_high);
105 			dm_pci_write_config32(dev, reg_addr, 0xffffffff);
106 			dm_pci_read_config32(dev, reg_addr, &size_high);
107 			dm_pci_write_config32(dev, reg_addr, base_high);
108 			bar_cnt--;
109 			reg_addr += 4;
110 			is_64 = 1;
111 		}
112 
113 		base = base | ((u64)base_high << 32);
114 		size = size | ((u64)size_high << 32);
115 
116 		if ((!is_64 && size_low) || (is_64 && size)) {
117 			size = ~size + 1;
118 			printf(" %d   %#018llx  %#018llx  %d     %s   %s\n",
119 			       bar_id, (unsigned long long)base,
120 			       (unsigned long long)size, is_64 ? 64 : 32,
121 			       is_io ? "I/O" : "MEM",
122 			       prefetchable ? "Prefetchable" : "");
123 		}
124 
125 		bar_id++;
126 		bar_cnt--;
127 	}
128 
129 	return 0;
130 }
131 
132 static struct pci_reg_info regs_start[] = {
133 	{ "vendor ID", PCI_SIZE_16, PCI_VENDOR_ID },
134 	{ "device ID", PCI_SIZE_16, PCI_DEVICE_ID },
135 	{ "command register ID", PCI_SIZE_16, PCI_COMMAND },
136 	{ "status register", PCI_SIZE_16, PCI_STATUS },
137 	{ "revision ID", PCI_SIZE_8, PCI_REVISION_ID },
138 	{},
139 };
140 
141 static struct pci_reg_info regs_rest[] = {
142 	{ "sub class code", PCI_SIZE_8, PCI_CLASS_SUB_CODE },
143 	{ "programming interface", PCI_SIZE_8, PCI_CLASS_PROG },
144 	{ "cache line", PCI_SIZE_8, PCI_CACHE_LINE_SIZE },
145 	{ "latency time", PCI_SIZE_8, PCI_LATENCY_TIMER },
146 	{ "header type", PCI_SIZE_8, PCI_HEADER_TYPE },
147 	{ "BIST", PCI_SIZE_8, PCI_BIST },
148 	{ "base address 0", PCI_SIZE_32, PCI_BASE_ADDRESS_0 },
149 	{},
150 };
151 
152 static struct pci_reg_info regs_normal[] = {
153 	{ "base address 1", PCI_SIZE_32, PCI_BASE_ADDRESS_1 },
154 	{ "base address 2", PCI_SIZE_32, PCI_BASE_ADDRESS_2 },
155 	{ "base address 3", PCI_SIZE_32, PCI_BASE_ADDRESS_3 },
156 	{ "base address 4", PCI_SIZE_32, PCI_BASE_ADDRESS_4 },
157 	{ "base address 5", PCI_SIZE_32, PCI_BASE_ADDRESS_5 },
158 	{ "cardBus CIS pointer", PCI_SIZE_32, PCI_CARDBUS_CIS },
159 	{ "sub system vendor ID", PCI_SIZE_16, PCI_SUBSYSTEM_VENDOR_ID },
160 	{ "sub system ID", PCI_SIZE_16, PCI_SUBSYSTEM_ID },
161 	{ "expansion ROM base address", PCI_SIZE_32, PCI_ROM_ADDRESS },
162 	{ "interrupt line", PCI_SIZE_8, PCI_INTERRUPT_LINE },
163 	{ "interrupt pin", PCI_SIZE_8, PCI_INTERRUPT_PIN },
164 	{ "min Grant", PCI_SIZE_8, PCI_MIN_GNT },
165 	{ "max Latency", PCI_SIZE_8, PCI_MAX_LAT },
166 	{},
167 };
168 
169 static struct pci_reg_info regs_bridge[] = {
170 	{ "base address 1", PCI_SIZE_32, PCI_BASE_ADDRESS_1 },
171 	{ "primary bus number", PCI_SIZE_8, PCI_PRIMARY_BUS },
172 	{ "secondary bus number", PCI_SIZE_8, PCI_SECONDARY_BUS },
173 	{ "subordinate bus number", PCI_SIZE_8, PCI_SUBORDINATE_BUS },
174 	{ "secondary latency timer", PCI_SIZE_8, PCI_SEC_LATENCY_TIMER },
175 	{ "IO base", PCI_SIZE_8, PCI_IO_BASE },
176 	{ "IO limit", PCI_SIZE_8, PCI_IO_LIMIT },
177 	{ "secondary status", PCI_SIZE_16, PCI_SEC_STATUS },
178 	{ "memory base", PCI_SIZE_16, PCI_MEMORY_BASE },
179 	{ "memory limit", PCI_SIZE_16, PCI_MEMORY_LIMIT },
180 	{ "prefetch memory base", PCI_SIZE_16, PCI_PREF_MEMORY_BASE },
181 	{ "prefetch memory limit", PCI_SIZE_16, PCI_PREF_MEMORY_LIMIT },
182 	{ "prefetch memory base upper", PCI_SIZE_32, PCI_PREF_BASE_UPPER32 },
183 	{ "prefetch memory limit upper", PCI_SIZE_32, PCI_PREF_LIMIT_UPPER32 },
184 	{ "IO base upper 16 bits", PCI_SIZE_16, PCI_IO_BASE_UPPER16 },
185 	{ "IO limit upper 16 bits", PCI_SIZE_16, PCI_IO_LIMIT_UPPER16 },
186 	{ "expansion ROM base address", PCI_SIZE_32, PCI_ROM_ADDRESS1 },
187 	{ "interrupt line", PCI_SIZE_8, PCI_INTERRUPT_LINE },
188 	{ "interrupt pin", PCI_SIZE_8, PCI_INTERRUPT_PIN },
189 	{ "bridge control", PCI_SIZE_16, PCI_BRIDGE_CONTROL },
190 	{},
191 };
192 
193 static struct pci_reg_info regs_cardbus[] = {
194 	{ "capabilities", PCI_SIZE_8, PCI_CB_CAPABILITY_LIST },
195 	{ "secondary status", PCI_SIZE_16, PCI_CB_SEC_STATUS },
196 	{ "primary bus number", PCI_SIZE_8, PCI_CB_PRIMARY_BUS },
197 	{ "CardBus number", PCI_SIZE_8, PCI_CB_CARD_BUS },
198 	{ "subordinate bus number", PCI_SIZE_8, PCI_CB_SUBORDINATE_BUS },
199 	{ "CardBus latency timer", PCI_SIZE_8, PCI_CB_LATENCY_TIMER },
200 	{ "CardBus memory base 0", PCI_SIZE_32, PCI_CB_MEMORY_BASE_0 },
201 	{ "CardBus memory limit 0", PCI_SIZE_32, PCI_CB_MEMORY_LIMIT_0 },
202 	{ "CardBus memory base 1", PCI_SIZE_32, PCI_CB_MEMORY_BASE_1 },
203 	{ "CardBus memory limit 1", PCI_SIZE_32, PCI_CB_MEMORY_LIMIT_1 },
204 	{ "CardBus IO base 0", PCI_SIZE_16, PCI_CB_IO_BASE_0 },
205 	{ "CardBus IO base high 0", PCI_SIZE_16, PCI_CB_IO_BASE_0_HI },
206 	{ "CardBus IO limit 0", PCI_SIZE_16, PCI_CB_IO_LIMIT_0 },
207 	{ "CardBus IO limit high 0", PCI_SIZE_16, PCI_CB_IO_LIMIT_0_HI },
208 	{ "CardBus IO base 1", PCI_SIZE_16, PCI_CB_IO_BASE_1 },
209 	{ "CardBus IO base high 1", PCI_SIZE_16, PCI_CB_IO_BASE_1_HI },
210 	{ "CardBus IO limit 1", PCI_SIZE_16, PCI_CB_IO_LIMIT_1 },
211 	{ "CardBus IO limit high 1", PCI_SIZE_16, PCI_CB_IO_LIMIT_1_HI },
212 	{ "interrupt line", PCI_SIZE_8, PCI_INTERRUPT_LINE },
213 	{ "interrupt pin", PCI_SIZE_8, PCI_INTERRUPT_PIN },
214 	{ "bridge control", PCI_SIZE_16, PCI_CB_BRIDGE_CONTROL },
215 	{ "subvendor ID", PCI_SIZE_16, PCI_CB_SUBSYSTEM_VENDOR_ID },
216 	{ "subdevice ID", PCI_SIZE_16, PCI_CB_SUBSYSTEM_ID },
217 	{ "PC Card 16bit base address", PCI_SIZE_32, PCI_CB_LEGACY_MODE_BASE },
218 	{},
219 };
220 
221 /**
222  * pci_header_show() - Show the header of the specified PCI device.
223  *
224  * @dev: Bus+Device+Function number
225  */
226 static void pci_header_show(struct udevice *dev)
227 {
228 	unsigned long class, header_type;
229 
230 	dm_pci_read_config(dev, PCI_CLASS_CODE, &class, PCI_SIZE_8);
231 	dm_pci_read_config(dev, PCI_HEADER_TYPE, &header_type, PCI_SIZE_8);
232 	pci_show_regs(dev, regs_start);
233 	printf("  class code =                  0x%.2x (%s)\n", (int)class,
234 	       pci_class_str(class));
235 	pci_show_regs(dev, regs_rest);
236 
237 	switch (header_type & 0x03) {
238 	case PCI_HEADER_TYPE_NORMAL:	/* "normal" PCI device */
239 		pci_show_regs(dev, regs_normal);
240 		break;
241 	case PCI_HEADER_TYPE_BRIDGE:	/* PCI-to-PCI bridge */
242 		pci_show_regs(dev, regs_bridge);
243 		break;
244 	case PCI_HEADER_TYPE_CARDBUS:	/* PCI-to-CardBus bridge */
245 		pci_show_regs(dev, regs_cardbus);
246 		break;
247 
248 	default:
249 		printf("unknown header\n");
250 		break;
251     }
252 }
253 
254 static void pciinfo_header(int busnum, bool short_listing)
255 {
256 	printf("Scanning PCI devices on bus %d\n", busnum);
257 
258 	if (short_listing) {
259 		printf("BusDevFun  VendorId   DeviceId   Device Class       Sub-Class\n");
260 		printf("_____________________________________________________________\n");
261 	}
262 }
263 
264 /**
265  * pci_header_show_brief() - Show the short-form PCI device header
266  *
267  * Reads and prints the header of the specified PCI device in short form.
268  *
269  * @dev: PCI device to show
270  */
271 static void pci_header_show_brief(struct udevice *dev)
272 {
273 	ulong vendor, device;
274 	ulong class, subclass;
275 
276 	dm_pci_read_config(dev, PCI_VENDOR_ID, &vendor, PCI_SIZE_16);
277 	dm_pci_read_config(dev, PCI_DEVICE_ID, &device, PCI_SIZE_16);
278 	dm_pci_read_config(dev, PCI_CLASS_CODE, &class, PCI_SIZE_8);
279 	dm_pci_read_config(dev, PCI_CLASS_SUB_CODE, &subclass, PCI_SIZE_8);
280 
281 	printf("0x%.4lx     0x%.4lx     %-23s 0x%.2lx\n",
282 	       vendor, device,
283 	       pci_class_str(class), subclass);
284 }
285 
286 static void pciinfo(struct udevice *bus, bool short_listing)
287 {
288 	struct udevice *dev;
289 
290 	pciinfo_header(bus->seq, short_listing);
291 
292 	for (device_find_first_child(bus, &dev);
293 	     dev;
294 	     device_find_next_child(&dev)) {
295 		struct pci_child_platdata *pplat;
296 
297 		pplat = dev_get_parent_platdata(dev);
298 		if (short_listing) {
299 			printf("%02x.%02x.%02x   ", bus->seq,
300 			       PCI_DEV(pplat->devfn), PCI_FUNC(pplat->devfn));
301 			pci_header_show_brief(dev);
302 		} else {
303 			printf("\nFound PCI device %02x.%02x.%02x:\n", bus->seq,
304 			       PCI_DEV(pplat->devfn), PCI_FUNC(pplat->devfn));
305 			pci_header_show(dev);
306 		}
307 	}
308 }
309 
310 /**
311  * get_pci_dev() - Convert the "bus.device.function" identifier into a number
312  *
313  * @name: Device string in the form "bus.device.function" where each is in hex
314  * @return encoded pci_dev_t or -1 if the string was invalid
315  */
316 static pci_dev_t get_pci_dev(char *name)
317 {
318 	char cnum[12];
319 	int len, i, iold, n;
320 	int bdfs[3] = {0,0,0};
321 
322 	len = strlen(name);
323 	if (len > 8)
324 		return -1;
325 	for (i = 0, iold = 0, n = 0; i < len; i++) {
326 		if (name[i] == '.') {
327 			memcpy(cnum, &name[iold], i - iold);
328 			cnum[i - iold] = '\0';
329 			bdfs[n++] = simple_strtoul(cnum, NULL, 16);
330 			iold = i + 1;
331 		}
332 	}
333 	strcpy(cnum, &name[iold]);
334 	if (n == 0)
335 		n = 1;
336 	bdfs[n] = simple_strtoul(cnum, NULL, 16);
337 
338 	return PCI_BDF(bdfs[0], bdfs[1], bdfs[2]);
339 }
340 
341 static int pci_cfg_display(struct udevice *dev, ulong addr,
342 			   enum pci_size_t size, ulong length)
343 {
344 #define DISP_LINE_LEN	16
345 	ulong i, nbytes, linebytes;
346 	int byte_size;
347 	int rc = 0;
348 
349 	byte_size = pci_byte_size(size);
350 	if (length == 0)
351 		length = 0x40 / byte_size; /* Standard PCI config space */
352 
353 	/* Print the lines.
354 	 * once, and all accesses are with the specified bus width.
355 	 */
356 	nbytes = length * byte_size;
357 	do {
358 		printf("%08lx:", addr);
359 		linebytes = (nbytes > DISP_LINE_LEN) ? DISP_LINE_LEN : nbytes;
360 		for (i = 0; i < linebytes; i += byte_size) {
361 			unsigned long val;
362 
363 			dm_pci_read_config(dev, addr, &val, size);
364 			printf(" %0*lx", pci_field_width(size), val);
365 			addr += byte_size;
366 		}
367 		printf("\n");
368 		nbytes -= linebytes;
369 		if (ctrlc()) {
370 			rc = 1;
371 			break;
372 		}
373 	} while (nbytes > 0);
374 
375 	return (rc);
376 }
377 
378 static int pci_cfg_modify(struct udevice *dev, ulong addr, ulong size,
379 			  ulong value, int incrflag)
380 {
381 	ulong	i;
382 	int	nbytes;
383 	ulong val;
384 
385 	/* Print the address, followed by value.  Then accept input for
386 	 * the next value.  A non-converted value exits.
387 	 */
388 	do {
389 		printf("%08lx:", addr);
390 		dm_pci_read_config(dev, addr, &val, size);
391 		printf(" %0*lx", pci_field_width(size), val);
392 
393 		nbytes = cli_readline(" ? ");
394 		if (nbytes == 0 || (nbytes == 1 && console_buffer[0] == '-')) {
395 			/* <CR> pressed as only input, don't modify current
396 			 * location and move to next. "-" pressed will go back.
397 			 */
398 			if (incrflag)
399 				addr += nbytes ? -size : size;
400 			nbytes = 1;
401 			/* good enough to not time out */
402 			bootretry_reset_cmd_timeout();
403 		}
404 #ifdef CONFIG_BOOT_RETRY_TIME
405 		else if (nbytes == -2) {
406 			break;	/* timed out, exit the command	*/
407 		}
408 #endif
409 		else {
410 			char *endp;
411 			i = simple_strtoul(console_buffer, &endp, 16);
412 			nbytes = endp - console_buffer;
413 			if (nbytes) {
414 				/* good enough to not time out
415 				 */
416 				bootretry_reset_cmd_timeout();
417 				dm_pci_write_config(dev, addr, i, size);
418 				if (incrflag)
419 					addr += size;
420 			}
421 		}
422 	} while (nbytes);
423 
424 	return 0;
425 }
426 
427 static const struct pci_flag_info {
428 	uint flag;
429 	const char *name;
430 } pci_flag_info[] = {
431 	{ PCI_REGION_IO, "io" },
432 	{ PCI_REGION_PREFETCH, "prefetch" },
433 	{ PCI_REGION_SYS_MEMORY, "sysmem" },
434 	{ PCI_REGION_RO, "readonly" },
435 	{ PCI_REGION_IO, "io" },
436 };
437 
438 static void pci_show_regions(struct udevice *bus)
439 {
440 	struct pci_controller *hose = dev_get_uclass_priv(bus);
441 	const struct pci_region *reg;
442 	int i, j;
443 
444 	if (!hose) {
445 		printf("Bus '%s' is not a PCI controller\n", bus->name);
446 		return;
447 	}
448 
449 	printf("#   %-18s %-18s %-18s  %s\n", "Bus start", "Phys start", "Size",
450 	       "Flags");
451 	for (i = 0, reg = hose->regions; i < hose->region_count; i++, reg++) {
452 		printf("%d   %#018llx %#018llx %#018llx  ", i,
453 		       (unsigned long long)reg->bus_start,
454 		       (unsigned long long)reg->phys_start,
455 		       (unsigned long long)reg->size);
456 		if (!(reg->flags & PCI_REGION_TYPE))
457 			printf("mem ");
458 		for (j = 0; j < ARRAY_SIZE(pci_flag_info); j++) {
459 			if (reg->flags & pci_flag_info[j].flag)
460 				printf("%s ", pci_flag_info[j].name);
461 		}
462 		printf("\n");
463 	}
464 }
465 
466 /* PCI Configuration Space access commands
467  *
468  * Syntax:
469  *	pci display[.b, .w, .l] bus.device.function} [addr] [len]
470  *	pci next[.b, .w, .l] bus.device.function [addr]
471  *      pci modify[.b, .w, .l] bus.device.function [addr]
472  *      pci write[.b, .w, .l] bus.device.function addr value
473  */
474 static int do_pci(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
475 {
476 	ulong addr = 0, value = 0, cmd_size = 0;
477 	enum pci_size_t size = PCI_SIZE_32;
478 	struct udevice *dev, *bus;
479 	int busnum = 0;
480 	pci_dev_t bdf = 0;
481 	char cmd = 's';
482 	int ret = 0;
483 
484 	if (argc > 1)
485 		cmd = argv[1][0];
486 
487 	switch (cmd) {
488 	case 'd':		/* display */
489 	case 'n':		/* next */
490 	case 'm':		/* modify */
491 	case 'w':		/* write */
492 		/* Check for a size specification. */
493 		cmd_size = cmd_get_data_size(argv[1], 4);
494 		size = (cmd_size == 4) ? PCI_SIZE_32 : cmd_size - 1;
495 		if (argc > 3)
496 			addr = simple_strtoul(argv[3], NULL, 16);
497 		if (argc > 4)
498 			value = simple_strtoul(argv[4], NULL, 16);
499 	case 'h':		/* header */
500 	case 'b':		/* bars */
501 		if (argc < 3)
502 			goto usage;
503 		if ((bdf = get_pci_dev(argv[2])) == -1)
504 			return 1;
505 		break;
506 	case 'e':
507 		pci_init();
508 		return 0;
509 	case 'r': /* no break */
510 	default:		/* scan bus */
511 		value = 1; /* short listing */
512 		if (argc > 1) {
513 			if (cmd != 'r' && argv[argc-1][0] == 'l') {
514 				value = 0;
515 				argc--;
516 			}
517 			if (argc > 1)
518 				busnum = simple_strtoul(argv[1], NULL, 16);
519 		}
520 		ret = uclass_get_device_by_seq(UCLASS_PCI, busnum, &bus);
521 		if (ret) {
522 			printf("No such bus\n");
523 			return CMD_RET_FAILURE;
524 		}
525 		if (cmd == 'r')
526 			pci_show_regions(bus);
527 		else
528 			pciinfo(bus, value);
529 		return 0;
530 	}
531 
532 	ret = dm_pci_bus_find_bdf(bdf, &dev);
533 	if (ret) {
534 		printf("No such device\n");
535 		return CMD_RET_FAILURE;
536 	}
537 
538 	switch (argv[1][0]) {
539 	case 'h':		/* header */
540 		pci_header_show(dev);
541 		break;
542 	case 'd':		/* display */
543 		return pci_cfg_display(dev, addr, size, value);
544 	case 'n':		/* next */
545 		if (argc < 4)
546 			goto usage;
547 		ret = pci_cfg_modify(dev, addr, size, value, 0);
548 		break;
549 	case 'm':		/* modify */
550 		if (argc < 4)
551 			goto usage;
552 		ret = pci_cfg_modify(dev, addr, size, value, 1);
553 		break;
554 	case 'w':		/* write */
555 		if (argc < 5)
556 			goto usage;
557 		ret = dm_pci_write_config(dev, addr, value, size);
558 		break;
559 	case 'b':		/* bars */
560 		return pci_bar_show(dev);
561 	default:
562 		ret = CMD_RET_USAGE;
563 		break;
564 	}
565 
566 	return ret;
567  usage:
568 	return CMD_RET_USAGE;
569 }
570 
571 /***************************************************/
572 
573 #ifdef CONFIG_SYS_LONGHELP
574 static char pci_help_text[] =
575 	"[bus] [long]\n"
576 	"    - short or long list of PCI devices on bus 'bus'\n"
577 	"pci enum\n"
578 	"    - Enumerate PCI buses\n"
579 	"pci header b.d.f\n"
580 	"    - show header of PCI device 'bus.device.function'\n"
581 	"pci bar b.d.f\n"
582 	"    - show BARs base and size for device b.d.f'\n"
583 	"pci regions\n"
584 	"    - show PCI regions\n"
585 	"pci display[.b, .w, .l] b.d.f [address] [# of objects]\n"
586 	"    - display PCI configuration space (CFG)\n"
587 	"pci next[.b, .w, .l] b.d.f address\n"
588 	"    - modify, read and keep CFG address\n"
589 	"pci modify[.b, .w, .l] b.d.f address\n"
590 	"    -  modify, auto increment CFG address\n"
591 	"pci write[.b, .w, .l] b.d.f address value\n"
592 	"    - write to CFG address";
593 #endif
594 
595 U_BOOT_CMD(
596 	pci,	5,	1,	do_pci,
597 	"list and access PCI Configuration Space", pci_help_text
598 );
599