blob: f0f97c516f8c29e0c73b8019b1019532eaa051ab [file] [log] [blame]
// Support for enabling/disabling BIOS ram shadowing.
//
// Copyright (C) 2008,2009 Kevin O'Connor <kevin@koconnor.net>
// Copyright (C) 2006 Fabrice Bellard
//
// This file may be distributed under the terms of the GNU LGPLv3 license.
#include "util.h" // memcpy
#include "pci.h" // pci_config_writeb
#include "config.h" // CONFIG_*
#include "pci_ids.h" // PCI_VENDOR_ID_INTEL
// Test if 'addr' is in the range from 'start'..'start+size'
#define IN_RANGE(addr, start, size) ({ \
u32 __addr = (addr); \
u32 __start = (start); \
u32 __size = (size); \
(__addr - __start < __size); \
})
// On the emulators, the bios at 0xf0000 is also at 0xffff0000
#define BIOS_SRC_ADDR 0xffff0000
// Enable shadowing and copy bios.
static void
__make_bios_writable(u16 bdf)
{
// Make ram from 0xc0000-0xf0000 writable
int clear = 0;
int i;
for (i=0; i<6; i++) {
if (CONFIG_OPTIONROMS_DEPLOYED) {
int reg = pci_config_readb(bdf, 0x5a + i);
if ((reg & 0x11) != 0x11) {
// Need to copy optionroms to work around qemu implementation
void *mem = (void*)(BUILD_ROM_START + i * 32*1024);
memcpy((void*)BUILD_BIOS_TMP_ADDR, mem, 32*1024);
pci_config_writeb(bdf, 0x5a + i, 0x33);
memcpy(mem, (void*)BUILD_BIOS_TMP_ADDR, 32*1024);
clear = 1;
} else {
pci_config_writeb(bdf, 0x5a + i, 0x33);
}
} else {
pci_config_writeb(bdf, 0x5a + i, 0x33);
}
}
if (clear)
memset((void*)BUILD_BIOS_TMP_ADDR, 0, 32*1024);
// Make ram from 0xf0000-0x100000 writable
int reg = pci_config_readb(bdf, 0x59);
pci_config_writeb(bdf, 0x59, 0x30);
if (reg & 0x10)
// Ram already present.
return;
// Copy bios.
memcpy((void*)BUILD_BIOS_ADDR, (void*)BIOS_SRC_ADDR, BUILD_BIOS_SIZE);
}
// Make the 0xc0000-0x100000 area read/writable.
void
make_bios_writable()
{
if (CONFIG_COREBOOT)
return;
dprintf(3, "enabling shadow ram\n");
// Locate chip controlling ram shadowing.
int bdf = pci_find_device(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82441);
if (bdf < 0) {
dprintf(1, "Unable to unlock ram - bridge not found\n");
return;
}
int reg = pci_config_readb(bdf, 0x59);
if (!(reg & 0x10)) {
// QEMU doesn't fully implement the piix shadow capabilities -
// if ram isn't backing the bios segment when shadowing is
// disabled, the code itself wont be in memory. So, run the
// code from the high-memory flash location.
u32 pos = (u32)__make_bios_writable - BUILD_BIOS_ADDR + BIOS_SRC_ADDR;
void (*func)(u16 bdf) = (void*)pos;
func(bdf);
return;
}
// Ram already present - just enable writes
__make_bios_writable(bdf);
}
// Make the BIOS code segment area (0xf0000) read-only.
void
make_bios_readonly()
{
if (CONFIG_COREBOOT)
return;
dprintf(3, "locking shadow ram\n");
int bdf = pci_find_device(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82441);
if (bdf < 0) {
dprintf(1, "Unable to lock ram - bridge not found\n");
return;
}
// Flush any pending writes before locking memory.
wbinvd();
// Write protect roms from 0xc0000-0xf0000
int i;
for (i=0; i<6; i++) {
u32 mem = BUILD_ROM_START + i * 32*1024;
if (RomEnd <= mem + 16*1024) {
if (RomEnd > mem)
pci_config_writeb(bdf, 0x5a + i, 0x31);
break;
}
pci_config_writeb(bdf, 0x5a + i, 0x11);
}
// Write protect 0xf0000-0x100000
pci_config_writeb(bdf, 0x59, 0x10);
}