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[PATCH] x86-64: Don't reserve ROMs

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We trust the e820 table, so explicitely reserving ROMs shouldn't
be needed.

Signed-off-by: Andi Kleen <ak@suse.de>
This commit is contained in:
Andi Kleen 2007-02-13 13:26:24 +01:00 committed by Andi Kleen
parent 00edefae05
commit fc986db4fc
1 changed files with 2 additions and 128 deletions
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130
arch/x86_64/kernel/setup.c
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@ -138,128 +138,6 @@ struct resource code_resource = {
.flags = IORESOURCE_RAM,
};
#define IORESOURCE_ROM (IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM)
static struct resource system_rom_resource = {
.name = "System ROM",
.start = 0xf0000,
.end = 0xfffff,
.flags = IORESOURCE_ROM,
};
static struct resource extension_rom_resource = {
.name = "Extension ROM",
.start = 0xe0000,
.end = 0xeffff,
.flags = IORESOURCE_ROM,
};
static struct resource adapter_rom_resources[] = {
{ .name = "Adapter ROM", .start = 0xc8000, .end = 0,
.flags = IORESOURCE_ROM },
{ .name = "Adapter ROM", .start = 0, .end = 0,
.flags = IORESOURCE_ROM },
{ .name = "Adapter ROM", .start = 0, .end = 0,
.flags = IORESOURCE_ROM },
{ .name = "Adapter ROM", .start = 0, .end = 0,
.flags = IORESOURCE_ROM },
{ .name = "Adapter ROM", .start = 0, .end = 0,
.flags = IORESOURCE_ROM },
{ .name = "Adapter ROM", .start = 0, .end = 0,
.flags = IORESOURCE_ROM }
};
static struct resource video_rom_resource = {
.name = "Video ROM",
.start = 0xc0000,
.end = 0xc7fff,
.flags = IORESOURCE_ROM,
};
static struct resource video_ram_resource = {
.name = "Video RAM area",
.start = 0xa0000,
.end = 0xbffff,
.flags = IORESOURCE_RAM,
};
#define romsignature(x) (*(unsigned short *)(x) == 0xaa55)
static int __init romchecksum(unsigned char *rom, unsigned long length)
{
unsigned char *p, sum = 0;
for (p = rom; p < rom + length; p++)
sum += *p;
return sum == 0;
}
static void __init probe_roms(void)
{
unsigned long start, length, upper;
unsigned char *rom;
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;
/* 0 < length <= 0x7f * 512, historically */
length = rom[2] * 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 = extension_rom_resource.end - extension_rom_resource.start + 1;
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;
/* 0 < length <= 0x7f * 512, historically */
length = rom[2] * 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;
}
}
#ifdef CONFIG_PROC_VMCORE
/* elfcorehdr= specifies the location of elf core header
* stored by the crashed kernel. This option will be passed
@ -524,15 +402,11 @@ void __init setup_arch(char **cmdline_p)
init_apic_mappings();
/*
* Request address space for all standard RAM and ROM resources
* and also for regions reported as reserved by the e820.
*/
probe_roms();
* We trust e820 completely. No explicit ROM probing in memory.
*/
e820_reserve_resources();
e820_mark_nosave_regions();
request_resource(&iomem_resource, &video_ram_resource);
{
unsigned i;
/* request I/O space for devices used on all i[345]86 PCs */