[linux-2.6-block.git] / drivers / pci / rom.c

/*
 * drivers/pci/rom.c
 *
 * (C) Copyright 2004 Jon Smirl <jonsmirl@yahoo.com>
 * (C) Copyright 2004 Silicon Graphics, Inc. Jesse Barnes <jbarnes@sgi.com>
 *
 * PCI ROM access routines
 */
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/slab.h>

#include "pci.h"

/**
 * pci_enable_rom - enable ROM decoding for a PCI device
 * @pdev: PCI device to enable
 *
 * Enable ROM decoding on @dev.  This involves simply turning on the last
 * bit of the PCI ROM BAR.  Note that some cards may share address decoders
 * between the ROM and other resources, so enabling it may disable access
 * to MMIO registers or other card memory.
 */
static int pci_enable_rom(struct pci_dev *pdev)
{
	struct resource *res = pdev->resource + PCI_ROM_RESOURCE;
	struct pci_bus_region region;
	u32 rom_addr;

	if (!res->flags)
		return -1;

	pcibios_resource_to_bus(pdev, &region, res);
	pci_read_config_dword(pdev, pdev->rom_base_reg, &rom_addr);
	rom_addr &= ~PCI_ROM_ADDRESS_MASK;
	rom_addr |= region.start | PCI_ROM_ADDRESS_ENABLE;
	pci_write_config_dword(pdev, pdev->rom_base_reg, rom_addr);
	return 0;
}

/**
 * pci_disable_rom - disable ROM decoding for a PCI device
 * @pdev: PCI device to disable
 *
 * Disable ROM decoding on a PCI device by turning off the last bit in the
 * ROM BAR.
 */
static void pci_disable_rom(struct pci_dev *pdev)
{
	u32 rom_addr;
	pci_read_config_dword(pdev, pdev->rom_base_reg, &rom_addr);
	rom_addr &= ~PCI_ROM_ADDRESS_ENABLE;
	pci_write_config_dword(pdev, pdev->rom_base_reg, rom_addr);
}

/**
 * pci_map_rom - map a PCI ROM to kernel space
 * @pdev: pointer to pci device struct
 * @size: pointer to receive size of pci window over ROM
 * @return: kernel virtual pointer to image of ROM
 *
 * Map a PCI ROM into kernel space. If ROM is boot video ROM,
 * the shadow BIOS copy will be returned instead of the
 * actual ROM.
 */
void __iomem *pci_map_rom(struct pci_dev *pdev, size_t *size)
{
	struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
	loff_t start;
	void __iomem *rom;
	void __iomem *image;
	int last_image;

	/* IORESOURCE_ROM_SHADOW only set on x86 */
	if (res->flags & IORESOURCE_ROM_SHADOW) {
		/* primary video rom always starts here */
		start = (loff_t)0xC0000;
		*size = 0x20000; /* cover C000:0 through E000:0 */
	} else {
		if (res->flags & IORESOURCE_ROM_COPY) {
			*size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
			return (void __iomem *)pci_resource_start(pdev,
							     PCI_ROM_RESOURCE);
		} else {
			/* assign the ROM an address if it doesn't have one */
			if (res->parent == NULL &&
			    pci_assign_resource(pdev,PCI_ROM_RESOURCE))
				return NULL;
			start = pci_resource_start(pdev, PCI_ROM_RESOURCE);
			*size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
			if (*size == 0)
				return NULL;

			/* Enable ROM space decodes */
			if (pci_enable_rom(pdev))
				return NULL;
		}
	}

	rom = ioremap(start, *size);
	if (!rom) {
		/* restore enable if ioremap fails */
		if (!(res->flags & (IORESOURCE_ROM_ENABLE |
				    IORESOURCE_ROM_SHADOW |
				    IORESOURCE_ROM_COPY)))
			pci_disable_rom(pdev);
		return NULL;
	}

	/*
	 * Try to find the true size of the ROM since sometimes the PCI window
	 * size is much larger than the actual size of the ROM.
	 * True size is important if the ROM is going to be copied.
	 */
	image = rom;
	do {
		void __iomem *pds;
		/* Standard PCI ROMs start out with these bytes 55 AA */
		if (readb(image) != 0x55)
			break;
		if (readb(image + 1) != 0xAA)
			break;
		/* get the PCI data structure and check its signature */
		pds = image + readw(image + 24);
		if (readb(pds) != 'P')
			break;
		if (readb(pds + 1) != 'C')
			break;
		if (readb(pds + 2) != 'I')
			break;
		if (readb(pds + 3) != 'R')
			break;
		last_image = readb(pds + 21) & 0x80;
		/* this length is reliable */
		image += readw(pds + 16) * 512;
	} while (!last_image);

	/* never return a size larger than the PCI resource window */
	/* there are known ROMs that get the size wrong */
	*size = min((size_t)(image - rom), *size);

	return rom;
}

/**
 * pci_map_rom_copy - map a PCI ROM to kernel space, create a copy
 * @pdev: pointer to pci device struct
 * @size: pointer to receive size of pci window over ROM
 * @return: kernel virtual pointer to image of ROM
 *
 * Map a PCI ROM into kernel space. If ROM is boot video ROM,
 * the shadow BIOS copy will be returned instead of the
 * actual ROM.
 */
void __iomem *pci_map_rom_copy(struct pci_dev *pdev, size_t *size)
{
	struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
	void __iomem *rom;

	rom = pci_map_rom(pdev, size);
	if (!rom)
		return NULL;

	if (res->flags & (IORESOURCE_ROM_COPY | IORESOURCE_ROM_SHADOW))
		return rom;

	res->start = (unsigned long)kmalloc(*size, GFP_KERNEL);
	if (!res->start)
		return rom;

	res->end = res->start + *size;
	memcpy_fromio((void*)res->start, rom, *size);
	pci_unmap_rom(pdev, rom);
	res->flags |= IORESOURCE_ROM_COPY;

	return (void __iomem *)res->start;
}

/**
 * pci_unmap_rom - unmap the ROM from kernel space
 * @pdev: pointer to pci device struct
 * @rom: virtual address of the previous mapping
 *
 * Remove a mapping of a previously mapped ROM
 */
void pci_unmap_rom(struct pci_dev *pdev, void __iomem *rom)
{
	struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];

	if (res->flags & IORESOURCE_ROM_COPY)
		return;

	iounmap(rom);

	/* Disable again before continuing, leave enabled if pci=rom */
	if (!(res->flags & (IORESOURCE_ROM_ENABLE | IORESOURCE_ROM_SHADOW)))
		pci_disable_rom(pdev);
}

/**
 * pci_remove_rom - disable the ROM and remove its sysfs attribute
 * @pdev: pointer to pci device struct
 *
 * Remove the rom file in sysfs and disable ROM decoding.
 */
void pci_remove_rom(struct pci_dev *pdev)
{
	struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];

	if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
		sysfs_remove_bin_file(&pdev->dev.kobj, pdev->rom_attr);
	if (!(res->flags & (IORESOURCE_ROM_ENABLE |
			    IORESOURCE_ROM_SHADOW |
			    IORESOURCE_ROM_COPY)))
		pci_disable_rom(pdev);
}

/**
 * pci_cleanup_rom - internal routine for freeing the ROM copy created
 * by pci_map_rom_copy called from remove.c
 * @pdev: pointer to pci device struct
 *
 * Free the copied ROM if we allocated one.
 */
void pci_cleanup_rom(struct pci_dev *pdev)
{
	struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
	if (res->flags & IORESOURCE_ROM_COPY) {
		kfree((void*)res->start);
		res->flags &= ~IORESOURCE_ROM_COPY;
		res->start = 0;
		res->end = 0;
	}
}

EXPORT_SYMBOL(pci_map_rom);
EXPORT_SYMBOL(pci_map_rom_copy);
EXPORT_SYMBOL(pci_unmap_rom);
EXPORT_SYMBOL(pci_remove_rom);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* drivers/pci/rom.c
	3	*
	4	* (C) Copyright 2004 Jon Smirl <jonsmirl@yahoo.com>
	5	* (C) Copyright 2004 Silicon Graphics, Inc. Jesse Barnes <jbarnes@sgi.com>
	6	*
	7	* PCI ROM access routines
	8	*/
	9	#include <linux/config.h>
	10	#include <linux/kernel.h>
	11	#include <linux/pci.h>
4e57b681	12	#include <linux/slab.h>
1da177e4 LT	13
	14	#include "pci.h"
	15
	16	/**
	17	* pci_enable_rom - enable ROM decoding for a PCI device
67be2dd1	18	* @pdev: PCI device to enable
1da177e4 LT	19	*
	20	* Enable ROM decoding on @dev. This involves simply turning on the last
	21	* bit of the PCI ROM BAR. Note that some cards may share address decoders
	22	* between the ROM and other resources, so enabling it may disable access
	23	* to MMIO registers or other card memory.
	24	*/
8085ce08	25	static int pci_enable_rom(struct pci_dev *pdev)
1da177e4	26	{
8085ce08 BH	27	struct resource *res = pdev->resource + PCI_ROM_RESOURCE;
8085ce08 BH	28	struct pci_bus_region region;
1da177e4 LT	29	u32 rom_addr;
1da177e4 LT	30
8085ce08 BH	31	if (!res->flags)
	32	return -1;
	33
	34	pcibios_resource_to_bus(pdev, &region, res);
1da177e4	35	pci_read_config_dword(pdev, pdev->rom_base_reg, &rom_addr);
8085ce08 BH	36	rom_addr &= ~PCI_ROM_ADDRESS_MASK;
8085ce08 BH	37	rom_addr \|= region.start \| PCI_ROM_ADDRESS_ENABLE;
1da177e4	38	pci_write_config_dword(pdev, pdev->rom_base_reg, rom_addr);
8085ce08	39	return 0;
1da177e4 LT	40	}
	41
	42	/**
	43	* pci_disable_rom - disable ROM decoding for a PCI device
67be2dd1	44	* @pdev: PCI device to disable
1da177e4 LT	45	*
	46	* Disable ROM decoding on a PCI device by turning off the last bit in the
	47	* ROM BAR.
	48	*/
	49	static void pci_disable_rom(struct pci_dev *pdev)
	50	{
	51	u32 rom_addr;
	52	pci_read_config_dword(pdev, pdev->rom_base_reg, &rom_addr);
	53	rom_addr &= ~PCI_ROM_ADDRESS_ENABLE;
	54	pci_write_config_dword(pdev, pdev->rom_base_reg, rom_addr);
	55	}
	56
	57	/**
	58	* pci_map_rom - map a PCI ROM to kernel space
67be2dd1	59	* @pdev: pointer to pci device struct
1da177e4 LT	60	* @size: pointer to receive size of pci window over ROM
	61	* @return: kernel virtual pointer to image of ROM
	62	*
	63	* Map a PCI ROM into kernel space. If ROM is boot video ROM,
	64	* the shadow BIOS copy will be returned instead of the
	65	* actual ROM.
	66	*/
	67	void __iomem pci_map_rom(struct pci_dev pdev, size_t *size)
	68	{
	69	struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
	70	loff_t start;
	71	void __iomem *rom;
	72	void __iomem *image;
	73	int last_image;
	74
	75	/* IORESOURCE_ROM_SHADOW only set on x86 */
	76	if (res->flags & IORESOURCE_ROM_SHADOW) {
	77	/* primary video rom always starts here */
	78	start = (loff_t)0xC0000;
	79	size = 0x20000; / cover C000:0 through E000:0 */
	80	} else {
	81	if (res->flags & IORESOURCE_ROM_COPY) {
	82	*size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
8085ce08 BH	83	return (void __iomem *)pci_resource_start(pdev,
8085ce08 BH	84	PCI_ROM_RESOURCE);
1da177e4 LT	85	} else {
1da177e4 LT	86	/* assign the ROM an address if it doesn't have one */
8085ce08 BH	87	if (res->parent == NULL &&
	88	pci_assign_resource(pdev,PCI_ROM_RESOURCE))
	89	return NULL;
1da177e4 LT	90	start = pci_resource_start(pdev, PCI_ROM_RESOURCE);
	91	*size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
	92	if (*size == 0)
	93	return NULL;
	94
	95	/* Enable ROM space decodes */
8085ce08 BH	96	if (pci_enable_rom(pdev))
8085ce08 BH	97	return NULL;
1da177e4 LT	98	}
	99	}
	100
	101	rom = ioremap(start, *size);
	102	if (!rom) {
	103	/* restore enable if ioremap fails */
	104	if (!(res->flags & (IORESOURCE_ROM_ENABLE \|
	105	IORESOURCE_ROM_SHADOW \|
	106	IORESOURCE_ROM_COPY)))
	107	pci_disable_rom(pdev);
	108	return NULL;
	109	}
	110
	111	/*
	112	* Try to find the true size of the ROM since sometimes the PCI window
	113	* size is much larger than the actual size of the ROM.
	114	* True size is important if the ROM is going to be copied.
	115	*/
	116	image = rom;
	117	do {
	118	void __iomem *pds;
	119	/* Standard PCI ROMs start out with these bytes 55 AA */
	120	if (readb(image) != 0x55)
	121	break;
	122	if (readb(image + 1) != 0xAA)
	123	break;
	124	/* get the PCI data structure and check its signature */
	125	pds = image + readw(image + 24);
	126	if (readb(pds) != 'P')
	127	break;
	128	if (readb(pds + 1) != 'C')
	129	break;
	130	if (readb(pds + 2) != 'I')
	131	break;
	132	if (readb(pds + 3) != 'R')
	133	break;
	134	last_image = readb(pds + 21) & 0x80;
	135	/* this length is reliable */
	136	image += readw(pds + 16) * 512;
	137	} while (!last_image);
	138
761a3ac0 JS	139	/* never return a size larger than the PCI resource window */
	140	/* there are known ROMs that get the size wrong */
	141	size = min((size_t)(image - rom), size);
1da177e4 LT	142
	143	return rom;
	144	}
	145
	146	/**
	147	* pci_map_rom_copy - map a PCI ROM to kernel space, create a copy
67be2dd1	148	* @pdev: pointer to pci device struct
1da177e4 LT	149	* @size: pointer to receive size of pci window over ROM
	150	* @return: kernel virtual pointer to image of ROM
	151	*
	152	* Map a PCI ROM into kernel space. If ROM is boot video ROM,
	153	* the shadow BIOS copy will be returned instead of the
	154	* actual ROM.
	155	*/
	156	void __iomem pci_map_rom_copy(struct pci_dev pdev, size_t *size)
	157	{
	158	struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
	159	void __iomem *rom;
	160
	161	rom = pci_map_rom(pdev, size);
	162	if (!rom)
	163	return NULL;
	164
	165	if (res->flags & (IORESOURCE_ROM_COPY \| IORESOURCE_ROM_SHADOW))
	166	return rom;
	167
	168	res->start = (unsigned long)kmalloc(*size, GFP_KERNEL);
	169	if (!res->start)
	170	return rom;
	171
	172	res->end = res->start + *size;
	173	memcpy_fromio((void)res->start, rom, size);
	174	pci_unmap_rom(pdev, rom);
	175	res->flags \|= IORESOURCE_ROM_COPY;
	176
	177	return (void __iomem *)res->start;
	178	}
	179
	180	/**
	181	* pci_unmap_rom - unmap the ROM from kernel space
67be2dd1	182	* @pdev: pointer to pci device struct
1da177e4 LT	183	* @rom: virtual address of the previous mapping
	184	*
	185	* Remove a mapping of a previously mapped ROM
	186	*/
	187	void pci_unmap_rom(struct pci_dev pdev, void __iomem rom)
	188	{
	189	struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
	190
	191	if (res->flags & IORESOURCE_ROM_COPY)
	192	return;
	193
	194	iounmap(rom);
	195
	196	/* Disable again before continuing, leave enabled if pci=rom */
	197	if (!(res->flags & (IORESOURCE_ROM_ENABLE \| IORESOURCE_ROM_SHADOW)))
	198	pci_disable_rom(pdev);
	199	}
	200
	201	/**
	202	* pci_remove_rom - disable the ROM and remove its sysfs attribute
67be2dd1	203	* @pdev: pointer to pci device struct
1da177e4 LT	204	*
	205	* Remove the rom file in sysfs and disable ROM decoding.
	206	*/
	207	void pci_remove_rom(struct pci_dev *pdev)
	208	{
	209	struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
	210
	211	if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
	212	sysfs_remove_bin_file(&pdev->dev.kobj, pdev->rom_attr);
	213	if (!(res->flags & (IORESOURCE_ROM_ENABLE \|
	214	IORESOURCE_ROM_SHADOW \|
	215	IORESOURCE_ROM_COPY)))
	216	pci_disable_rom(pdev);
	217	}
	218
	219	/**
	220	* pci_cleanup_rom - internal routine for freeing the ROM copy created
	221	* by pci_map_rom_copy called from remove.c
67be2dd1	222	* @pdev: pointer to pci device struct
1da177e4 LT	223	*
	224	* Free the copied ROM if we allocated one.
	225	*/
	226	void pci_cleanup_rom(struct pci_dev *pdev)
	227	{
	228	struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
	229	if (res->flags & IORESOURCE_ROM_COPY) {
	230	kfree((void*)res->start);
	231	res->flags &= ~IORESOURCE_ROM_COPY;
	232	res->start = 0;
	233	res->end = 0;
	234	}
	235	}
	236
	237	EXPORT_SYMBOL(pci_map_rom);
	238	EXPORT_SYMBOL(pci_map_rom_copy);
	239	EXPORT_SYMBOL(pci_unmap_rom);
	240	EXPORT_SYMBOL(pci_remove_rom);