From e037f9f17473b0bd21b8ca63b1cb9479652f3b6b Mon Sep 17 00:00:00 2001 From: Florian Zumbiehl Date: Tue, 1 Nov 2011 20:17:13 +0100 Subject: add support for writing to SMBus with vt8237 Change-Id: I70fe072f8f3447d0be7b7ac64508a954fe47091d Signed-off-by: Florian Zumbiehl Reviewed-on: http://review.coreboot.org/372 Tested-by: build bot (Jenkins) Reviewed-by: Rudolf Marek --- src/southbridge/via/vt8237r/early_smbus.c | 31 +++++++++++++++++++++---------- src/southbridge/via/vt8237r/vt8237r.h | 1 + 2 files changed, 22 insertions(+), 10 deletions(-) (limited to 'src/southbridge/via') diff --git a/src/southbridge/via/vt8237r/early_smbus.c b/src/southbridge/via/vt8237r/early_smbus.c index a298e84676..e25535bf0f 100644 --- a/src/southbridge/via/vt8237r/early_smbus.c +++ b/src/southbridge/via/vt8237r/early_smbus.c @@ -87,17 +87,12 @@ static void smbus_reset(void) PRINT_DEBUG("\n"); } -/** - * Read a byte from the SMBus. - * - * @param dimm The address location of the DIMM on the SMBus. - * @param offset The offset the data is located at. - */ -u8 smbus_read_byte(u8 dimm, u8 offset) +static u8 smbus_transaction(u8 dimm, u8 offset, u8 data, int do_read) { u8 val; - PRINT_DEBUG("DIMM "); + PRINT_DEBUG(do_read ? "RD: " : "WR: "); + PRINT_DEBUG("ADDR "); PRINT_DEBUG_HEX16(dimm); PRINT_DEBUG(" OFFSET "); PRINT_DEBUG_HEX16(offset); @@ -106,13 +101,13 @@ u8 smbus_read_byte(u8 dimm, u8 offset) smbus_reset(); /* Clear host data port. */ - outb(0x00, SMBHSTDAT0); + outb(do_read ? 0x00 : data, SMBHSTDAT0); SMBUS_DELAY(); smbus_wait_until_ready(); /* Actual addr to reg format. */ dimm = (dimm << 1); - dimm |= 1; + dimm |= !!do_read; outb(dimm, SMBXMITADD); outb(offset, SMBHSTCMD); @@ -132,6 +127,22 @@ u8 smbus_read_byte(u8 dimm, u8 offset) return val; } +/** + * Read a byte from the SMBus. + * + * @param dimm The address location of the DIMM on the SMBus. + * @param offset The offset the data is located at. + */ +u8 smbus_read_byte(u8 dimm, u8 offset) +{ + return smbus_transaction(dimm, offset, 0, 1); +} + +void smbus_write_byte(u8 dimm, u8 offset, u8 data) +{ + smbus_transaction(dimm, offset, data, 0); +} + #define PSONREADY_TIMEOUT 0x7fffffff static device_t get_vt8237_lpc(void) diff --git a/src/southbridge/via/vt8237r/vt8237r.h b/src/southbridge/via/vt8237r/vt8237r.h index 94b1840361..9d5a1fc608 100644 --- a/src/southbridge/via/vt8237r/vt8237r.h +++ b/src/southbridge/via/vt8237r/vt8237r.h @@ -148,6 +148,7 @@ __attribute__ ((packed)) #ifdef __PRE_RAM__ #ifndef __ROMCC__ u8 smbus_read_byte(u8 dimm, u8 offset); +void smbus_write_byte(u8 dimm, u8 offset, u8 data); void enable_smbus(void); void smbus_fixup(const struct mem_controller *ctrl); // these are in vt8237_early_smbus.c - do they really belong there? -- cgit v1.2.3