From f3b9fd32658a9a6788b87431464b84cda3c3c24b Mon Sep 17 00:00:00 2001 From: Timothy Pearson Date: Thu, 11 Jun 2015 16:14:15 -0500 Subject: src/northbridge/amd/amdmct: Add option to override bad SPD checksum Certain DIMMs, for example DIMMs on which the EEPROM has been modified by the end user, may not contain a valid SPD checksum. While this is not a normal condition, it may be useful to allow a checksum override while memory timing parameters are being altered, e.g. in the course of overclocking or underclocking, or when recovering from a bad SPD write. This is an advanced level feature primarily useful for debugging and development. Change-Id: Ia743a13348d0a6e5e4dfffa04ed9582e0f7f3dad Signed-off-by: Timothy Pearson Reviewed-on: http://review.coreboot.org/11987 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer Reviewed-by: Alexandru Gagniuc --- src/northbridge/amd/amdmct/mct_ddr3/mct_d.c | 5 +++-- src/northbridge/amd/amdmct/wrappers/mcti_d.c | 8 ++++++++ 2 files changed, 11 insertions(+), 2 deletions(-) (limited to 'src') diff --git a/src/northbridge/amd/amdmct/mct_ddr3/mct_d.c b/src/northbridge/amd/amdmct/mct_ddr3/mct_d.c index 2841b18c6d..4bfb08aafc 100644 --- a/src/northbridge/amd/amdmct/mct_ddr3/mct_d.c +++ b/src/northbridge/amd/amdmct/mct_ddr3/mct_d.c @@ -1456,7 +1456,7 @@ restartinit: } } if (NodesWmem == 0) { - printk(BIOS_DEBUG, "No Nodes?!\n"); + printk(BIOS_ALERT, "Unable to detect valid memory on any nodes. Halting!\n"); goto fatalexit; } @@ -3892,13 +3892,14 @@ static u8 DIMMPresence_D(struct MCTStatStruc *pMCTstat, read_spd_bytes(pMCTstat, pDCTstat, i); crc_status = crcCheck(pDCTstat, i); } - if (crc_status) { /* CRC is OK */ + if ((crc_status) || (SPDCtrl == 2)) { /* CRC is OK */ byte = pDCTstat->spd_data.spd_bytes[i][SPD_TYPE]; if (byte == JED_DDR3SDRAM) { /*Dimm is 'Present'*/ pDCTstat->DIMMValid |= 1 << i; } } else { + printk(BIOS_WARNING, "Node %d DIMM %d: SPD checksum invalid\n", pDCTstat->Node_ID, i); pDCTstat->DIMMSPDCSE = 1 << i; if (SPDCtrl == 0) { pDCTstat->ErrStatus |= 1 << SB_DIMMChkSum; diff --git a/src/northbridge/amd/amdmct/wrappers/mcti_d.c b/src/northbridge/amd/amdmct/wrappers/mcti_d.c index 45f817791b..f49e973a68 100644 --- a/src/northbridge/amd/amdmct/wrappers/mcti_d.c +++ b/src/northbridge/amd/amdmct/wrappers/mcti_d.c @@ -146,6 +146,14 @@ static u16 mctGet_NVbits(u8 index) case NV_SPDCHK_RESTRT: val = 0; /* Exit current node initialization if any DIMM has SPD checksum error */ //val = 1; /* Ignore faulty SPD checksum (DIMM will still be disabled), continue current node intialization */ + //val = 2; /* Override faulty SPD checksum (DIMM will be enabled), continue current node intialization */ + + if (get_option(&nvram, "dimm_spd_checksum") == CB_SUCCESS) + val = nvram & 0x3; + + if (val > 2) + val = 2; + break; case NV_DQSTrainCTL: //val = 0; /*Skip dqs training */ -- cgit v1.2.3