Add support for Intel PIIX4/PIIX4E/PIIX4M-based mainboards
Tested on real hardware, reading, detecting and writing various chips works.
Corresponding to flashrom svn r68 and coreboot v2 svn r2489.
Signed-off-by: Uwe Hermann <uwe@hermann-uwe.de>
Acked-by: Stefan Reinauer <stepan@coresystems.de>
diff --git a/flash_enable.c b/flash_enable.c
index 6c894e7..187b61d 100644
--- a/flash_enable.c
+++ b/flash_enable.c
@@ -77,6 +77,37 @@
return 0;
}
+/* Datasheet: http://www.intel.com/design/intarch/datashts/290562.htm */
+static int enable_flash_piix4(struct pci_dev *dev, char *name)
+{
+ uint16_t old, new;
+ uint16_t xbcs = 0x4e; /* X-Bus Chip Select register. */
+
+ old = pci_read_word(dev, xbcs);
+
+ /* Set bit 9: 1-Meg Extended BIOS Enable (PCI master accesses to
+ FFF00000-FFF7FFFF are forwarded to ISA).
+ Set bit 7: Extended BIOS Enable (PCI master accesses to
+ FFF80000-FFFDFFFF are forwarded to ISA).
+ Set bit 6: Lower BIOS Enable (PCI master, or ISA master accesses to
+ the lower 64-Kbyte BIOS block (E00000EFFFF) at the top
+ of 1 Mbyte, or the aliases at the top of 4 Gbyte
+ (FFFE0000-FFFEFFF) result in the generation of BIOSCS#.
+ Set bit 2: BIOSCS# Write Protect Enable (1=enable, 0=disable). */
+ new = old | 0x2c4;
+
+ if (new == old)
+ return 0;
+
+ pci_write_word(dev, xbcs, new);
+
+ if (pci_read_word(dev, xbcs) != new) {
+ printf("tried to set 0x%x to 0x%x on %s failed (WARNING ONLY)\n", xbcs, new, name);
+ return -1;
+ }
+ return 0;
+}
+
static int enable_flash_ich(struct pci_dev *dev, char *name, int bios_cntl)
{
/* register 4e.b gets or'ed with one */
@@ -362,6 +393,7 @@
static FLASH_ENABLE enables[] = {
{0x1039, 0x0630, "SIS630", enable_flash_sis630},
+ {0x8086, 0x7110, "PIIX4/PIIX4E/PIIX4M", enable_flash_piix4},
{0x8086, 0x2410, "ICH", enable_flash_ich_4e},
{0x8086, 0x2420, "ICH0", enable_flash_ich_4e},
{0x8086, 0x2440, "ICH2", enable_flash_ich_4e},