This patch enables SB700 option PrefetchEnSPIFromHost in early setup. It affects only systems booting from SPI flash, not those booting from LPC flash. By default, the SB700 reads dwords from the SPI flash chip. Setting PrefetchEnSPIFromHost causes the SB700 to read entire cache lines from the flash chip.
Thanks, Scott Signed-off-by: Scott Duplichan <[email protected]> Index: src/southbridge/amd/sb700/sb700_early_setup.c =================================================================== --- src/southbridge/amd/sb700/sb700_early_setup.c (revision 5964) +++ src/southbridge/amd/sb700/sb700_early_setup.c (working copy) @@ -129,6 +129,11 @@ reg8 |= (1 << 5) | (1 << 6); pci_write_config8(dev, 0x47, reg8); + /* Enable PrefetchEnSPIFromHost to speed up SPI flash read (does not affect LPC) */ + reg8 = pci_read_config8(dev, 0xbb); + reg8 |= 1 << 0; + pci_write_config8(dev, 0xbb, reg8); + /* SuperIO, LPC ROM */ reg8 = pci_read_config8(dev, 0x48); /* Decode ports 0x2e-0x2f, 0x4e-0x4f (SuperI/O configuration) */ -- coreboot mailing list: [email protected] http://www.coreboot.org/mailman/listinfo/coreboot
