From fbdbcb713f1f1f184604a3a63e34904ee37a58d9 Mon Sep 17 00:00:00 2001 From: Kyösti Mälkki Date: Fri, 31 Jan 2014 20:32:54 +0200 Subject: AMD cimx/sb800: Set SPI frequency and prefetch MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Broken with/since commit d1cb0eec. Original intention was to set the frequency for 'Fast Read' command in bits 15..14, and enable 'Fast Read' command. Modified register contains SPI frequency for 'Normal Read' command in bits 13..12. Default for this is 11b for 16.5 MHz. Existing code unintentionally clears these bits, increasing SPI frequency to 66MHz for 'Normal Read' command. This is above specifications for many common SPI flash components and also makes flashrom older than 0.9.7-r1750 to operate unreliably on read/write/erase for these platforms. Change-Id: I30109e2a0410c0bb0bdc968ea71787396b32e761 Signed-off-by: Kyösti Mälkki Reviewed-on: http://review.coreboot.org/5089 Tested-by: build bot (Jenkins) Reviewed-by: Kevin O'Connor Reviewed-by: Paul Menzel Reviewed-by: Marc Jones --- src/southbridge/amd/cimx/sb800/bootblock.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'src') diff --git a/src/southbridge/amd/cimx/sb800/bootblock.c b/src/southbridge/amd/cimx/sb800/bootblock.c index ac9351e4c2..4fd2739442 100644 --- a/src/southbridge/amd/cimx/sb800/bootblock.c +++ b/src/southbridge/amd/cimx/sb800/bootblock.c @@ -66,7 +66,6 @@ static void enable_prefetch(void) static void enable_spi_fast_mode(void) { - u8 byte; u32 dword; device_t dev = PCI_DEV(0, 0x14, 0x03); @@ -76,8 +75,8 @@ static void enable_spi_fast_mode(void) pci_io_write_config32(dev, 0xa0, (u32) spi_base | 2); // early enable of SPI 33 MHz fast mode read - byte = spi_base[3]; - spi_base[3] = (byte & ~(3 << 14)) | (1 << 14); + dword = spi_base[3]; + spi_base[3] = (dword & ~(3 << 14)) | (1 << 14); spi_base[0] = spi_base[0] | (1 << 18); // fast read enable pci_io_write_config32(dev, 0xa0, save); -- cgit v1.2.3