From 7adcfde079324b834c9a6370af38e56e34f1c45c Mon Sep 17 00:00:00 2001 From: Jamie Chen Date: Thu, 16 Apr 2020 01:20:29 +0800 Subject: lib/spd_bin: add get_spd_sn function This patch adds the get_spd_sn function. It's for reading SODIMM serial number. In spd_cache implementation it can use to get serial number before reading whole SPD by smbus. BUG=b:146457985 BRANCH=None TEST=Wrote sample code to get the serial number and ran on puff. It can get the serial number correctly. Change-Id: I406bba7cc56debbd9851d430f069e4fb96ec937c Signed-off-by: Jamie Chen Reviewed-on: https://review.coreboot.org/c/coreboot/+/40414 Reviewed-by: Patrick Georgi Tested-by: build bot (Jenkins) --- src/soc/intel/common/block/smbus/smbuslib.c | 48 +++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) (limited to 'src/soc/intel/common/block') diff --git a/src/soc/intel/common/block/smbus/smbuslib.c b/src/soc/intel/common/block/smbus/smbuslib.c index f7192c85d4..5441b06219 100644 --- a/src/soc/intel/common/block/smbus/smbuslib.c +++ b/src/soc/intel/common/block/smbus/smbuslib.c @@ -79,3 +79,51 @@ void get_spd_smbus(struct spd_block *blk) update_spd_len(blk); } + +/* + * get_spd_sn returns the SODIMM serial number. It only supports DDR3 and DDR4. + * return CB_SUCCESS, sn is the serial number and sn=0xffffffff if the dimm is not present. + * return CB_ERR, if dram_type is not supported or addr is a zero. + */ +enum cb_err get_spd_sn(u8 addr, u32 *sn) +{ + u8 i; + u8 dram_type; + int smbus_ret; + + /* addr is not a zero. */ + if (addr == 0x0) + return CB_ERR; + + /* If dimm is not present, set sn to 0xff. */ + smbus_ret = do_smbus_read_byte(SMBUS_IO_BASE, addr, SPD_DRAM_TYPE); + if (smbus_ret < 0) { + printk(BIOS_INFO, "No memory dimm at address %02X\n", addr); + *sn = 0xffffffff; + return CB_SUCCESS; + } + + dram_type = smbus_ret & 0xff; + + /* Check if module is DDR4, DDR4 spd is 512 byte. */ + if (dram_type == SPD_DRAM_DDR4 && CONFIG_DIMM_SPD_SIZE > SPD_PAGE_LEN) { + /* Switch to page 1 */ + do_smbus_write_byte(SMBUS_IO_BASE, SPD_PAGE_1, 0, 0); + + for (i = 0; i < SPD_SN_LEN; i++) + *((u8 *)sn + i) = do_smbus_read_byte(SMBUS_IO_BASE, addr, + i + DDR4_SPD_SN_OFF); + + /* Restore to page 0 */ + do_smbus_write_byte(SMBUS_IO_BASE, SPD_PAGE_0, 0, 0); + } else if (dram_type == SPD_DRAM_DDR3) { + for (i = 0; i < SPD_SN_LEN; i++) + *((u8 *)sn + i) = do_smbus_read_byte(SMBUS_IO_BASE, addr, + i + DDR3_SPD_SN_OFF); + } else { + printk(BIOS_ERR, "Unsupported dram_type\n"); + return CB_ERR; + } + + return CB_SUCCESS; +} -- cgit v1.2.3