diff options
| -rw-r--r-- | chipset_enable.c | 47 |
1 files changed, 27 insertions, 20 deletions
diff --git a/chipset_enable.c b/chipset_enable.c index 39e59dd7..995d2c51 100644 --- a/chipset_enable.c +++ b/chipset_enable.c @@ -281,22 +281,15 @@ static int enable_flash_piix4(struct pci_dev *dev, const char *name) * See ie. page 375 of "Intel I/O Controller Hub 7 (ICH7) Family Datasheet" * http://download.intel.com/design/chipsets/datashts/30701303.pdf */ -static int enable_flash_ich(struct pci_dev *dev, const char *name, - int bios_cntl) +static int enable_flash_ich(struct pci_dev *dev, const char *name, uint8_t bios_cntl) { uint8_t old, new, wanted; /* - * Note: the ICH0-ICH5 BIOS_CNTL register is actually 16 bit wide, but + * Note: the ICH0-ICH5 BIOS_CNTL register is actually 16 bit wide, in Tunnel Creek it is even 32b, but * just treating it as 8 bit wide seems to work fine in practice. */ - old = pci_read_byte(dev, bios_cntl); - - msg_pdbg("\nBIOS Lock Enable: %sabled, ", - (old & (1 << 1)) ? "en" : "dis"); - msg_pdbg("BIOS Write Enable: %sabled, ", - (old & (1 << 0)) ? "en" : "dis"); - msg_pdbg("BIOS_CNTL is 0x%x\n", old); + wanted = old = pci_read_byte(dev, bios_cntl); /* * Quote from the 6 Series datasheet (Document Number: 324645-004): @@ -304,22 +297,36 @@ static int enable_flash_ich(struct pci_dev *dev, const char *name, * 1 = BIOS region SMM protection is enabled. * The BIOS Region is not writable unless all processors are in SMM." * In earlier chipsets this bit is reserved. + * + * Try to unset it in any case. + * It won't hurt and makes sense in some cases according to Stefan Reinauer. */ - if (old & (1 << 5)) + wanted &= ~(1 << 5); + + /* Set BIOS Write Enable */ + wanted |= (1 << 0); + + /* Only write the register if it's necessary */ + if (wanted != old) { + rpci_write_byte(dev, bios_cntl, wanted); + new = pci_read_byte(dev, bios_cntl); + } else + new = old; + + msg_pdbg("\nBIOS_CNTL = 0x%02x: ", new); + msg_pdbg("BIOS Lock Enable: %sabled, ", (new & (1 << 1)) ? "en" : "dis"); + msg_pdbg("BIOS Write Enable: %sabled\n", (new & (1 << 0)) ? "en" : "dis"); + if (new & (1 << 5)) msg_pinfo("WARNING: BIOS region SMM protection is enabled!\n"); - wanted = old | 1; - if (wanted == old) - return 0; - rpci_write_byte(dev, bios_cntl, wanted); + if (new != wanted) + msg_pinfo("WARNING: Setting Bios Control at 0x%x from 0x%02x to 0x%02x on %s failed.\n" + "New value is 0x%02x.\n", bios_cntl, old, wanted, name, new); - if ((new = pci_read_byte(dev, bios_cntl)) != wanted) { - msg_pinfo("WARNING: Setting 0x%x from 0x%x to 0x%x on %s " - "failed. New value is 0x%x.\n", - bios_cntl, old, wanted, name, new); + /* Return an error if we could not set the write enable */ + if (!(new & (1 << 0))) return -1; - } return 0; } |