| #include "bios.h" |
| #include "pci.h" |
| #include "string.h" |
| |
| #define PCI_VENDOR_ID_INTEL 0x8086 |
| #define PCI_DEVICE_ID_INTEL_82441 0x1237 |
| #define PCI_DEVICE_ID_INTEL_Q35_MCH 0x29c0 |
| |
| #define I440FX_PAM0 0x59 |
| #define Q35_HOST_BRIDGE_PAM0 0x90 |
| |
| static void make_bios_writable(void) |
| { |
| const int bdf = 0; |
| const uint8_t *bios_start = (uint8_t *)0xffff0000; |
| uint8_t *low_start = (uint8_t *)0xf0000; |
| int pambase; |
| |
| uint32_t id = pci_config_readl(bdf, 0); |
| if (id == (PCI_VENDOR_ID_INTEL | (PCI_DEVICE_ID_INTEL_82441 << 16))) |
| pambase = I440FX_PAM0; |
| else if (id == (PCI_VENDOR_ID_INTEL | (PCI_DEVICE_ID_INTEL_Q35_MCH << 16))) |
| pambase = Q35_HOST_BRIDGE_PAM0; |
| else |
| panic(); |
| |
| // Make ram from 0xc0000-0xf0000 read-write |
| int i; |
| for (i=0; i<6; i++) { |
| int pam = pambase + 1 + i; |
| pci_config_writeb(bdf, pam, 0x33); |
| } |
| |
| // Make ram from 0xf0000-0x100000 read-write and shadow BIOS |
| // We're still running from 0xffff0000 |
| pci_config_writeb(bdf, pambase, 0x30); |
| memcpy(low_start, bios_start, 0x10000); |
| } |
| |
| |
| int main(void) |
| { |
| make_bios_writable(); |
| // extract_acpi(); |
| // extract_smbios(); |
| // extract_kernel(); |
| // boot_linux(); |
| panic(); |
| } |