Return to shadow.c CVS log

Up to [Qemu by Fabrice Bellard] / qemu / roms / seabios / src

Annotation of qemu/roms/seabios/src/shadow.c, revision 1.1

1.1     ! root        1: // Support for enabling/disabling BIOS ram shadowing.
        !             2: //
        !             3: // Copyright (C) 2008,2009  Kevin O'Connor <[email protected]>
        !             4: // Copyright (C) 2006 Fabrice Bellard
        !             5: //
        !             6: // This file may be distributed under the terms of the GNU LGPLv3 license.
        !             7: 
        !             8: #include "util.h" // memcpy
        !             9: #include "pci.h" // pci_config_writeb
        !            10: #include "config.h" // CONFIG_*
        !            11: #include "pci_ids.h" // PCI_VENDOR_ID_INTEL
        !            12: 
        !            13: // Test if 'addr' is in the range from 'start'..'start+size'
        !            14: #define IN_RANGE(addr, start, size) ({   \
        !            15:             u32 __addr = (addr);         \
        !            16:             u32 __start = (start);       \
        !            17:             u32 __size = (size);         \
        !            18:             (__addr - __start < __size); \
        !            19:         })
        !            20: 
        !            21: // On the emulators, the bios at 0xf0000 is also at 0xffff0000
        !            22: #define BIOS_SRC_ADDR 0xffff0000
        !            23: 
        !            24: // Enable shadowing and copy bios.
        !            25: static void
        !            26: __make_bios_writable(u16 bdf)
        !            27: {
        !            28:     // Make ram from 0xc0000-0xf0000 writable
        !            29:     int clear = 0;
        !            30:     int i;
        !            31:     for (i=0; i<6; i++) {
        !            32:         int reg = pci_config_readb(bdf, 0x5a + i);
        !            33:         if ((reg & 0x11) != 0x11) {
        !            34:             // Need to copy optionroms to work around qemu implementation
        !            35:             void *mem = (void*)(BUILD_ROM_START + i * 32*1024);
        !            36:             memcpy((void*)BUILD_BIOS_TMP_ADDR, mem, 32*1024);
        !            37:             pci_config_writeb(bdf, 0x5a + i, 0x33);
        !            38:             memcpy(mem, (void*)BUILD_BIOS_TMP_ADDR, 32*1024);
        !            39:             clear = 1;
        !            40:         } else {
        !            41:             pci_config_writeb(bdf, 0x5a + i, 0x33);
        !            42:         }
        !            43:     }
        !            44:     if (clear)
        !            45:         memset((void*)BUILD_BIOS_TMP_ADDR, 0, 32*1024);
        !            46: 
        !            47:     // Make ram from 0xf0000-0x100000 writable
        !            48:     int reg = pci_config_readb(bdf, 0x59);
        !            49:     pci_config_writeb(bdf, 0x59, 0x30);
        !            50:     if (reg & 0x10)
        !            51:         // Ram already present.
        !            52:         return;
        !            53: 
        !            54:     // Copy bios.
        !            55:     memcpy((void*)BUILD_BIOS_ADDR, (void*)BIOS_SRC_ADDR, BUILD_BIOS_SIZE);
        !            56: }
        !            57: 
        !            58: // Make the 0xc0000-0x100000 area read/writable.
        !            59: void
        !            60: make_bios_writable()
        !            61: {
        !            62:     if (CONFIG_COREBOOT)
        !            63:         return;
        !            64: 
        !            65:     dprintf(3, "enabling shadow ram\n");
        !            66: 
        !            67:     // Locate chip controlling ram shadowing.
        !            68:     int bdf = pci_find_device(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82441);
        !            69:     if (bdf < 0) {
        !            70:         dprintf(1, "Unable to unlock ram - bridge not found\n");
        !            71:         return;
        !            72:     }
        !            73: 
        !            74:     int reg = pci_config_readb(bdf, 0x59);
        !            75:     if (!(reg & 0x10)) {
        !            76:         // QEMU doesn't fully implement the piix shadow capabilities -
        !            77:         // if ram isn't backing the bios segment when shadowing is
        !            78:         // disabled, the code itself wont be in memory.  So, run the
        !            79:         // code from the high-memory flash location.
        !            80:         u32 pos = (u32)__make_bios_writable - BUILD_BIOS_ADDR + BIOS_SRC_ADDR;
        !            81:         void (*func)(u16 bdf) = (void*)pos;
        !            82:         func(bdf);
        !            83:         return;
        !            84:     }
        !            85:     // Ram already present - just enable writes
        !            86:     __make_bios_writable(bdf);
        !            87: }
        !            88: 
        !            89: // Make the BIOS code segment area (0xf0000) read-only.
        !            90: void
        !            91: make_bios_readonly()
        !            92: {
        !            93:     if (CONFIG_COREBOOT)
        !            94:         return;
        !            95: 
        !            96:     dprintf(3, "locking shadow ram\n");
        !            97: 
        !            98:     int bdf = pci_find_device(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82441);
        !            99:     if (bdf < 0) {
        !           100:         dprintf(1, "Unable to lock ram - bridge not found\n");
        !           101:         return;
        !           102:     }
        !           103: 
        !           104:     // Flush any pending writes before locking memory.
        !           105:     wbinvd();
        !           106: 
        !           107:     // Write protect roms from 0xc0000-0xf0000
        !           108:     int i;
        !           109:     for (i=0; i<6; i++) {
        !           110:         u32 mem = BUILD_ROM_START + i * 32*1024;
        !           111:         if (RomEnd <= mem + 16*1024) {
        !           112:             if (RomEnd > mem)
        !           113:                 pci_config_writeb(bdf, 0x5a + i, 0x31);
        !           114:             break;
        !           115:         }
        !           116:         pci_config_writeb(bdf, 0x5a + i, 0x11);
        !           117:     }
        !           118: 
        !           119:     // Write protect 0xf0000-0x100000
        !           120:     pci_config_writeb(bdf, 0x59, 0x10);
        !           121: }

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.