| // 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++) { |
| 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); |
| } |
| } |
| 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(void) |
| { |
| 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(void) |
| { |
| 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); |
| } |