• Greg Kroah-Hartman's avatar
    License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
    Greg Kroah-Hartman authored
    Many source files in the tree are missing licensing information, which
    makes it harder for compliance tools to determine the correct license.
    
    By default all files without license information are under the default
    license of the kernel, which is GPL version 2.
    
    Update the files which contain no license information with the 'GPL-2.0'
    SPDX license identifier.  The SPDX identifier is a legally binding
    shorthand, which can be used instead of the full boiler plate text.
    
    This patch is based on work done by Thomas Gleixner and Kate Stewart and
    Philippe Ombredanne.
    
    How this work was done:
    
    Patches were generated and checked against linux-4.14-rc6 for a subset of
    the use cases:
     - file had no licensing information it it.
     - file was a */uapi/* one with no licensing information in it,
     - file was a */uapi/* one with existing licensing information,
    
    Further patches will be generated in subsequent months to fix up cases
    where non-standard...
    b2441318
probe_roms.c 6.31 KB
// SPDX-License-Identifier: GPL-2.0
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/uaccess.h>
#include <linux/mmzone.h>
#include <linux/ioport.h>
#include <linux/seq_file.h>
#include <linux/console.h>
#include <linux/init.h>
#include <linux/edd.h>
#include <linux/dmi.h>
#include <linux/pfn.h>
#include <linux/pci.h>
#include <linux/export.h>

#include <asm/probe_roms.h>
#include <asm/pci-direct.h>
#include <asm/e820/api.h>
#include <asm/mmzone.h>
#include <asm/setup.h>
#include <asm/sections.h>
#include <asm/io.h>
#include <asm/setup_arch.h>

static struct resource system_rom_resource = {
	.name	= "System ROM",
	.start	= 0xf0000,
	.end	= 0xfffff,
	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
};

static struct resource extension_rom_resource = {
	.name	= "Extension ROM",
	.start	= 0xe0000,
	.end	= 0xeffff,
	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
};

static struct resource adapter_rom_resources[] = { {
	.name 	= "Adapter ROM",
	.start	= 0xc8000,
	.end	= 0,
	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
}, {
	.name 	= "Adapter ROM",
	.start	= 0,
	.end	= 0,
	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
}, {
	.name 	= "Adapter ROM",
	.start	= 0,
	.end	= 0,
	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
}, {
	.name 	= "Adapter ROM",
	.start	= 0,
	.end	= 0,
	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
}, {
	.name 	= "Adapter ROM",
	.start	= 0,
	.end	= 0,
	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
}, {
	.name 	= "Adapter ROM",
	.start	= 0,
	.end	= 0,
	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
} };

static struct resource video_rom_resource = {
	.name 	= "Video ROM",
	.start	= 0xc0000,
	.end	= 0xc7fff,
	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
};

/* does this oprom support the given pci device, or any of the devices
 * that the driver supports?
 */
static bool match_id(struct pci_dev *pdev, unsigned short vendor, unsigned short device)
{
	struct pci_driver *drv = pdev->driver;
	const struct pci_device_id *id;

	if (pdev->vendor == vendor && pdev->device == device)
		return true;

	for (id = drv ? drv->id_table : NULL; id && id->vendor; id++)
		if (id->vendor == vendor && id->device == device)
			break;

	return id && id->vendor;
}

static bool probe_list(struct pci_dev *pdev, unsigned short vendor,
		       const unsigned char *rom_list)
{
	unsigned short device;

	do {
		if (probe_kernel_address(rom_list, device) != 0)
			device = 0;

		if (device && match_id(pdev, vendor, device))
			break;

		rom_list += 2;
	} while (device);

	return !!device;
}

static struct resource *find_oprom(struct pci_dev *pdev)
{
	struct resource *oprom = NULL;
	int i;

	for (i = 0; i < ARRAY_SIZE(adapter_rom_resources); i++) {
		struct resource *res = &adapter_rom_resources[i];
		unsigned short offset, vendor, device, list, rev;
		const unsigned char *rom;

		if (res->end == 0)
			break;

		rom = isa_bus_to_virt(res->start);
		if (probe_kernel_address(rom + 0x18, offset) != 0)
			continue;

		if (probe_kernel_address(rom + offset + 0x4, vendor) != 0)
			continue;

		if (probe_kernel_address(rom + offset + 0x6, device) != 0)
			continue;

		if (match_id(pdev, vendor, device)) {
			oprom = res;
			break;
		}

		if (probe_kernel_address(rom + offset + 0x8, list) == 0 &&
		    probe_kernel_address(rom + offset + 0xc, rev) == 0 &&
		    rev >= 3 && list &&
		    probe_list(pdev, vendor, rom + offset + list)) {
			oprom = res;
			break;
		}
	}

	return oprom;
}

void __iomem *pci_map_biosrom(struct pci_dev *pdev)
{
	struct resource *oprom = find_oprom(pdev);

	if (!oprom)
		return NULL;

	return ioremap(oprom->start, resource_size(oprom));
}
EXPORT_SYMBOL(pci_map_biosrom);

void pci_unmap_biosrom(void __iomem *image)
{
	iounmap(image);
}
EXPORT_SYMBOL(pci_unmap_biosrom);

size_t pci_biosrom_size(struct pci_dev *pdev)
{
	struct resource *oprom = find_oprom(pdev);

	return oprom ? resource_size(oprom) : 0;
}
EXPORT_SYMBOL(pci_biosrom_size);

#define ROMSIGNATURE 0xaa55

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

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

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

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

void __init probe_roms(void)
{
	const unsigned char *rom;
	unsigned long start, length, upper;
	unsigned char c;
	int i;

	/* video rom */
	upper = adapter_rom_resources[0].start;
	for (start = video_rom_resource.start; start < upper; start += 2048) {
		rom = isa_bus_to_virt(start);
		if (!romsignature(rom))
			continue;

		video_rom_resource.start = start;

		if (probe_kernel_address(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;

		request_resource(&iomem_resource, &video_rom_resource);
		break;
	}

	start = (video_rom_resource.end + 1 + 2047) & ~2047UL;
	if (start < upper)
		start = upper;

	/* system rom */
	request_resource(&iomem_resource, &system_rom_resource);
	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 = resource_size(&extension_rom_resource);
		if (romchecksum(rom, length)) {
			request_resource(&iomem_resource, &extension_rom_resource);
			upper = extension_rom_resource.start;
		}
	}

	/* check for adapter roms on 2k boundaries */
	for (i = 0; i < ARRAY_SIZE(adapter_rom_resources) && start < upper; start += 2048) {
		rom = isa_bus_to_virt(start);
		if (!romsignature(rom))
			continue;

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

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

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

		adapter_rom_resources[i].start = start;
		adapter_rom_resources[i].end = start + length - 1;
		request_resource(&iomem_resource, &adapter_rom_resources[i]);

		start = adapter_rom_resources[i++].end & ~2047UL;
	}
}