[thirdparty/mdadm.git] / probe_roms.c

/*
 * probe_roms - scan for Adapter ROMS
 *
 * (based on linux-2.6:arch/x86/kernel/probe_roms_32.c)
 *
 * Copyright (C) 2008 Intel Corporation
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include "probe_roms.h"
#include "mdadm.h"
#include <unistd.h>
#include <signal.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <asm/types.h>

static void *rom_mem = MAP_FAILED;
static int rom_fd = -1;
static const int rom_len = 0xf0000 - 0xc0000; /* option-rom memory region */
static int _sigbus;
static unsigned long rom_align;

static void roms_deinit(void);
static int roms_init(void);

static void sigbus(int sig)
{
	_sigbus = 1;
}

static int probe_address8(const __u8 *ptr, __u8 *val)
{
	int rc = 0;

	*val = *ptr;
	if (_sigbus)
		rc = -1;
	_sigbus = 0;

	return rc;
}

static int probe_address16(const __u16 *ptr, __u16 *val)
{
	int rc = 0;

	*val = *ptr;
	if (_sigbus)
		rc = -1;
	_sigbus = 0;

	return rc;
}

void probe_roms_exit(void)
{
	signal(SIGBUS, SIG_DFL);
	if (rom_fd >= 0) {
		close(rom_fd);
		rom_fd = -1;
	}
	if (rom_mem != MAP_FAILED) {
		munmap(rom_mem, rom_len);
		rom_mem = MAP_FAILED;
	}
	roms_deinit();
}

int probe_roms_init(unsigned long align)
{
	int fd = -1;
	int rc = 0;

	/* valid values are 2048 and 512.  512 is for PCI-3.0 compliant
	 * systems, or systems that do not have dangerous/legacy ISA
	 * devices.  2048 should always be safe
	 */
	if (align == 512 || align == 2048)
		rom_align = align;
	else
		return -1;

	if (roms_init())
		return -1;

	if (signal(SIGBUS, sigbus) == SIG_ERR)
		rc = -1;
	if (rc == 0) {
		fd = open("/dev/mem", O_RDONLY);
		if (fd < 0)
			rc = -1;
	}
	if (rc == 0) {
		rom_mem = mmap(NULL, rom_len, PROT_READ, MAP_PRIVATE, fd, 0xc0000);
		if (rom_mem == MAP_FAILED)
			rc = -1;
	}

	if (rc == 0)
		rom_fd = fd;
	else {
		if (fd >= 0)
			close(fd);
		probe_roms_exit();
	}
	return rc;
}

/**
 * isa_bus_to_virt - convert physical address to mmap'd region
 * @addr - address to convert
 *
 * Only valid between a successful call to probe_roms_init and the
 * corresponding probe_roms_exit
 */
static void *isa_bus_to_virt(unsigned long addr)
{
	return rom_mem + (addr - 0xc0000);
}

struct resource {
	unsigned long start;
	unsigned long end;
	unsigned long data;
	const char *name;
	struct resource *next;
};

static struct resource system_rom_resource = {
	.name	= "System ROM",
	.start	= 0xf0000,
	.data   = 0,
	.end	= 0xfffff,
};

static struct resource extension_rom_resource = {
	.name	= "Extension ROM",
	.start	= 0xe0000,
	.data   = 0,
	.end	= 0xeffff,
};

static struct resource *adapter_rom_resources;

static struct resource video_rom_resource = {
	.name	= "Video ROM",
	.start	= 0xc0000,
	.data   = 0,
	.end	= 0xc7fff,
};

static int roms_init(void)
{
	adapter_rom_resources = malloc(sizeof(struct resource));
	if (adapter_rom_resources == NULL)
		return 1;
	adapter_rom_resources->name = "Adapter ROM";
	adapter_rom_resources->start = 0xc8000;
	adapter_rom_resources->data = 0;
	adapter_rom_resources->end = 0;
	adapter_rom_resources->next = NULL;
	return 0;
}

static void roms_deinit(void)
{
	struct resource *res;

	res = adapter_rom_resources;
	while (res) {
		struct resource *tmp = res;

		res = res->next;
		free(tmp);
	}
}

#define ROMSIGNATURE 0xaa55


static int romsignature(const unsigned char *rom)
{
	const unsigned short * const ptr = (const unsigned short *)rom;
	unsigned short sig = 0;

	return probe_address16(ptr, &sig) == 0 && sig == ROMSIGNATURE;
}

static int romchecksum(const unsigned char *rom, unsigned long length)
{
	unsigned char sum, c;

	for (sum = 0; length && probe_address8(rom++, &c) == 0; length--)
		sum += c;
	return !length && !sum;
}

int scan_adapter_roms(scan_fn fn)
{
	/* let scan_fn examing each of the adapter roms found by probe_roms */
	struct resource *res = adapter_rom_resources;
	int found;

	if (rom_fd < 0)
		return 0;

	found = 0;
	while (res) {
		if (res->start) {
			found = fn(isa_bus_to_virt(res->start),
				   isa_bus_to_virt(res->end),
				   isa_bus_to_virt(res->data));
			if (found)
				break;
		} else
			break;
		res = res->next;
	}

	return found;
}

static unsigned long align(unsigned long addr, unsigned long alignment)
{
	return (addr + alignment - 1) & ~(alignment - 1);
}

void probe_roms(void)
{
	const void *rom;
	unsigned long start, length, upper;
	unsigned char c;
	struct resource *res = adapter_rom_resources;
	__u16 val=0;

	if (rom_fd < 0)
		return;

	/* video rom */
	upper = res->start;
	for (start = video_rom_resource.start; start < upper; start += rom_align) {
		rom = isa_bus_to_virt(start);
		if (!romsignature(rom))
			continue;

		video_rom_resource.start = start;

		if (probe_address8(rom + 2, &c) != 0)
			continue;

		/* 0 < length <= 0x7f * 512, historically */
		length = c * 512;

		/* if checksum okay, trust length byte */
		if (length && romchecksum(rom, length))
			video_rom_resource.end = start + length - 1;
		break;
	}

	start = align(video_rom_resource.end + 1, rom_align);
	if (start < upper)
		start = upper;

	/* system rom */
	upper = system_rom_resource.start;

	/* check for extension rom (ignore length byte!) */
	rom = isa_bus_to_virt(extension_rom_resource.start);
	if (romsignature(rom)) {
		length = extension_rom_resource.end - extension_rom_resource.start + 1;
		if (romchecksum(rom, length))
			upper = extension_rom_resource.start;
	}

	struct resource *prev_res = res;
	/* check for adapter roms on 2k boundaries */
	for (; start < upper; start += rom_align) {
		rom = isa_bus_to_virt(start);
		if (!romsignature(rom))
			continue;

		if (probe_address8(rom + 2, &c) != 0)
			continue;

		/* 0 < length <= 0x7f * 512, historically */
		length = c * 512;

		/* Retrieve 16-bit pointer to PCI Data Structure (offset 18h-19h)
		 * The data can be within 64KB forward of the first location
		 * of this code image. The pointer is in little-endian order
		 */

		if (probe_address16(rom + 0x18, &val) != 0)
			continue;
		val = __le16_to_cpu(val);

		/* but accept any length that fits if checksum okay */
		if (!length || start + length > upper || !romchecksum(rom, length))
			continue;

		if (res == NULL) {
			res = calloc(1, sizeof(struct resource));
			if (res == NULL)
				return;
			prev_res->next = res;
		}

		res->start = start;
		res->data = start + (unsigned long)val;
		res->end = start + length - 1;

		start = res->end & ~(rom_align - 1);
		prev_res = res;
		res = res->next;
	}
}
Commit	Line	Data
39795f9c DW	1	/*
	2	* probe_roms - scan for Adapter ROMS
	3	*
	4	* (based on linux-2.6:arch/x86/kernel/probe_roms_32.c)
	5	*
	6	* Copyright (C) 2008 Intel Corporation
	7	*
	8	* This program is free software; you can redistribute it and/or modify it
	9	* under the terms and conditions of the GNU General Public License,
	10	* version 2, as published by the Free Software Foundation.
	11	*
	12	* This program is distributed in the hope it will be useful, but WITHOUT
	13	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	14	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	15	* more details.
	16	*
	17	* You should have received a copy of the GNU General Public License along with
	18	* this program; if not, write to the Free Software Foundation, Inc.,
	19	* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
	20	*/
	21
	22	#include "probe_roms.h"
3c8bfb5d	23	#include "mdadm.h"
39795f9c DW	24	#include <unistd.h>
	25	#include <signal.h>
	26	#include <fcntl.h>
	27	#include <sys/mman.h>
	28	#include <sys/stat.h>
	29	#include <sys/types.h>
	30	#include <asm/types.h>
	31
	32	static void *rom_mem = MAP_FAILED;
	33	static int rom_fd = -1;
f21e18ca	34	static const int rom_len = 0xf0000 - 0xc0000; /* option-rom memory region */
39795f9c	35	static int _sigbus;
969c2555 DW	36	static unsigned long rom_align;
969c2555 DW	37
4ec389e3 RS	38	static void roms_deinit(void);
	39	static int roms_init(void);
	40
39795f9c DW	41	static void sigbus(int sig)
	42	{
	43	_sigbus = 1;
	44	}
	45
	46	static int probe_address8(const __u8 ptr, __u8 val)
	47	{
	48	int rc = 0;
	49
	50	val = ptr;
	51	if (_sigbus)
	52	rc = -1;
	53	_sigbus = 0;
	54
	55	return rc;
	56	}
	57
	58	static int probe_address16(const __u16 ptr, __u16 val)
	59	{
	60	int rc = 0;
	61
	62	val = ptr;
	63	if (_sigbus)
	64	rc = -1;
	65	_sigbus = 0;
	66
	67	return rc;
	68	}
	69
	70	void probe_roms_exit(void)
	71	{
	72	signal(SIGBUS, SIG_DFL);
	73	if (rom_fd >= 0) {
	74	close(rom_fd);
	75	rom_fd = -1;
	76	}
	77	if (rom_mem != MAP_FAILED) {
	78	munmap(rom_mem, rom_len);
	79	rom_mem = MAP_FAILED;
	80	}
4ec389e3	81	roms_deinit();
39795f9c DW	82	}
39795f9c DW	83
969c2555	84	int probe_roms_init(unsigned long align)
39795f9c	85	{
922f66a9	86	int fd = -1;
39795f9c DW	87	int rc = 0;
39795f9c DW	88
969c2555 DW	89	/* valid values are 2048 and 512. 512 is for PCI-3.0 compliant
	90	* systems, or systems that do not have dangerous/legacy ISA
	91	* devices. 2048 should always be safe
	92	*/
	93	if (align == 512 \|\| align == 2048)
	94	rom_align = align;
	95	else
	96	return -1;
	97
4ec389e3 RS	98	if (roms_init())
	99	return -1;
	100
39795f9c DW	101	if (signal(SIGBUS, sigbus) == SIG_ERR)
	102	rc = -1;
	103	if (rc == 0) {
	104	fd = open("/dev/mem", O_RDONLY);
	105	if (fd < 0)
	106	rc = -1;
	107	}
	108	if (rc == 0) {
	109	rom_mem = mmap(NULL, rom_len, PROT_READ, MAP_PRIVATE, fd, 0xc0000);
	110	if (rom_mem == MAP_FAILED)
	111	rc = -1;
	112	}
	113
	114	if (rc == 0)
	115	rom_fd = fd;
922f66a9	116	else {
1011e834	117	if (fd >= 0)
922f66a9	118	close(fd);
39795f9c	119	probe_roms_exit();
922f66a9	120	}
39795f9c DW	121	return rc;
	122	}
	123
	124	/**
	125	* isa_bus_to_virt - convert physical address to mmap'd region
	126	* @addr - address to convert
	127	*
	128	* Only valid between a successful call to probe_roms_init and the
	129	* corresponding probe_roms_exit
	130	*/
	131	static void *isa_bus_to_virt(unsigned long addr)
	132	{
	133	return rom_mem + (addr - 0xc0000);
	134	}
	135
	136	struct resource {
	137	unsigned long start;
	138	unsigned long end;
3c8bfb5d	139	unsigned long data;
39795f9c	140	const char *name;
4ec389e3	141	struct resource *next;
39795f9c DW	142	};
	143
	144	static struct resource system_rom_resource = {
	145	.name = "System ROM",
	146	.start = 0xf0000,
3c8bfb5d	147	.data = 0,
39795f9c DW	148	.end = 0xfffff,
	149	};
	150
	151	static struct resource extension_rom_resource = {
	152	.name = "Extension ROM",
	153	.start = 0xe0000,
3c8bfb5d	154	.data = 0,
39795f9c DW	155	.end = 0xeffff,
	156	};
	157
4ec389e3	158	static struct resource *adapter_rom_resources;
39795f9c DW	159
39795f9c DW	160	static struct resource video_rom_resource = {
1011e834	161	.name = "Video ROM",
39795f9c	162	.start = 0xc0000,
3c8bfb5d	163	.data = 0,
39795f9c DW	164	.end = 0xc7fff,
	165	};
	166
4ec389e3 RS	167	static int roms_init(void)
	168	{
	169	adapter_rom_resources = malloc(sizeof(struct resource));
	170	if (adapter_rom_resources == NULL)
	171	return 1;
	172	adapter_rom_resources->name = "Adapter ROM";
	173	adapter_rom_resources->start = 0xc8000;
	174	adapter_rom_resources->data = 0;
	175	adapter_rom_resources->end = 0;
	176	adapter_rom_resources->next = NULL;
	177	return 0;
	178	}
	179
	180	static void roms_deinit(void)
	181	{
	182	struct resource *res;
	183
	184	res = adapter_rom_resources;
	185	while (res) {
	186	struct resource *tmp = res;
	187
	188	res = res->next;
	189	free(tmp);
	190	}
	191	}
	192
39795f9c DW	193	#define ROMSIGNATURE 0xaa55
39795f9c DW	194
4ec389e3	195
39795f9c DW	196	static int romsignature(const unsigned char *rom)
	197	{
	198	const unsigned short * const ptr = (const unsigned short *)rom;
	199	unsigned short sig = 0;
	200
	201	return probe_address16(ptr, &sig) == 0 && sig == ROMSIGNATURE;
	202	}
	203
	204	static int romchecksum(const unsigned char *rom, unsigned long length)
	205	{
	206	unsigned char sum, c;
	207
	208	for (sum = 0; length && probe_address8(rom++, &c) == 0; length--)
	209	sum += c;
	210	return !length && !sum;
	211	}
	212
	213	int scan_adapter_roms(scan_fn fn)
	214	{
	215	/* let scan_fn examing each of the adapter roms found by probe_roms */
4ec389e3	216	struct resource *res = adapter_rom_resources;
39795f9c DW	217	int found;
	218
	219	if (rom_fd < 0)
	220	return 0;
	221
	222	found = 0;
4ec389e3	223	while (res) {
39795f9c DW	224	if (res->start) {
39795f9c DW	225	found = fn(isa_bus_to_virt(res->start),
3c8bfb5d LM	226	isa_bus_to_virt(res->end),
3c8bfb5d LM	227	isa_bus_to_virt(res->data));
39795f9c DW	228	if (found)
	229	break;
	230	} else
	231	break;
4ec389e3	232	res = res->next;
39795f9c DW	233	}
	234
	235	return found;
	236	}
	237
969c2555 DW	238	static unsigned long align(unsigned long addr, unsigned long alignment)
	239	{
	240	return (addr + alignment - 1) & ~(alignment - 1);
	241	}
	242
39795f9c DW	243	void probe_roms(void)
	244	{
	245	const void *rom;
	246	unsigned long start, length, upper;
	247	unsigned char c;
4ec389e3	248	struct resource *res = adapter_rom_resources;
3c8bfb5d	249	__u16 val=0;
39795f9c DW	250
	251	if (rom_fd < 0)
	252	return;
	253
	254	/* video rom */
4ec389e3	255	upper = res->start;
969c2555	256	for (start = video_rom_resource.start; start < upper; start += rom_align) {
39795f9c DW	257	rom = isa_bus_to_virt(start);
	258	if (!romsignature(rom))
	259	continue;
	260
	261	video_rom_resource.start = start;
	262
	263	if (probe_address8(rom + 2, &c) != 0)
	264	continue;
	265
	266	/* 0 < length <= 0x7f * 512, historically */
	267	length = c * 512;
	268
	269	/* if checksum okay, trust length byte */
	270	if (length && romchecksum(rom, length))
	271	video_rom_resource.end = start + length - 1;
	272	break;
	273	}
	274
969c2555	275	start = align(video_rom_resource.end + 1, rom_align);
39795f9c DW	276	if (start < upper)
	277	start = upper;
	278
	279	/* system rom */
	280	upper = system_rom_resource.start;
	281
	282	/* check for extension rom (ignore length byte!) */
	283	rom = isa_bus_to_virt(extension_rom_resource.start);
	284	if (romsignature(rom)) {
	285	length = extension_rom_resource.end - extension_rom_resource.start + 1;
	286	if (romchecksum(rom, length))
	287	upper = extension_rom_resource.start;
	288	}
	289
4ec389e3	290	struct resource *prev_res = res;
39795f9c	291	/* check for adapter roms on 2k boundaries */
4ec389e3	292	for (; start < upper; start += rom_align) {
39795f9c DW	293	rom = isa_bus_to_virt(start);
	294	if (!romsignature(rom))
	295	continue;
	296
	297	if (probe_address8(rom + 2, &c) != 0)
	298	continue;
	299
	300	/* 0 < length <= 0x7f * 512, historically */
	301	length = c * 512;
	302
3c8bfb5d LM	303	/* Retrieve 16-bit pointer to PCI Data Structure (offset 18h-19h)
	304	* The data can be within 64KB forward of the first location
	305	* of this code image. The pointer is in little-endian order
	306	*/
	307
	308	if (probe_address16(rom + 0x18, &val) != 0)
	309	continue;
	310	val = __le16_to_cpu(val);
	311
39795f9c DW	312	/* but accept any length that fits if checksum okay */
	313	if (!length \|\| start + length > upper \|\| !romchecksum(rom, length))
	314	continue;
	315
4ec389e3 RS	316	if (res == NULL) {
	317	res = calloc(1, sizeof(struct resource));
	318	if (res == NULL)
	319	return;
	320	prev_res->next = res;
	321	}
	322
	323	res->start = start;
	324	res->data = start + (unsigned long)val;
	325	res->end = start + length - 1;
39795f9c	326
4ec389e3 RS	327	start = res->end & ~(rom_align - 1);
	328	prev_res = res;
	329	res = res->next;
39795f9c DW	330	}
39795f9c DW	331	}