Timothy Pearson (tpearson(a)raptorengineeringinc.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/11987
-gerrit
commit 058cf14316c87d81a3a7d033231e797b0f90ec12
Author: Timothy Pearson <tpearson(a)raptorengineeringinc.com>
Date: Thu Jun 11 16:14:15 2015 -0500
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 <tpearson(a)raptorengineeringinc.com>
---
src/mainboard/asus/kgpe-d16/cmos.default | 1 +
src/mainboard/asus/kgpe-d16/cmos.layout | 6 +++++-
src/northbridge/amd/amdmct/mct_ddr3/mct_d.c | 5 +++--
src/northbridge/amd/amdmct/wrappers/mcti_d.c | 8 ++++++++
4 files changed, 17 insertions(+), 3 deletions(-)
diff --git a/src/mainboard/asus/kgpe-d16/cmos.default b/src/mainboard/asus/kgpe-d16/cmos.default
index 0b87c91..3473bc9 100644
--- a/src/mainboard/asus/kgpe-d16/cmos.default
+++ b/src/mainboard/asus/kgpe-d16/cmos.default
@@ -8,6 +8,7 @@ nmi = Disable
hypertransport_speed_limit = Auto
max_mem_clock = DDR3-1600
minimum_memory_voltage = 1.5V
+dimm_spd_checksum = Enforce
ECC_memory = Enable
ECC_redirection = Enable
ecc_scrub_rate = 1.28us
diff --git a/src/mainboard/asus/kgpe-d16/cmos.layout b/src/mainboard/asus/kgpe-d16/cmos.layout
index 19c7e7d..0bc6db8 100644
--- a/src/mainboard/asus/kgpe-d16/cmos.layout
+++ b/src/mainboard/asus/kgpe-d16/cmos.layout
@@ -42,7 +42,8 @@ entries
466 1 e 1 cpu_cc6_state
467 1 e 1 sata_ahci_mode
468 4 h 0 maximum_p_state_limit
-473 1 r 0 allow_spd_nvram_cache_restore
+472 2 e 13 dimm_spd_checksum
+474 1 r 0 allow_spd_nvram_cache_restore
477 1 e 1 ieee1394_controller
728 256 h 0 user_data
984 16 h 0 check_sum
@@ -137,6 +138,9 @@ enumerations
12 1 1.35V
12 2 1.25V
12 3 1.15V
+13 0 Enforce
+13 1 Ignore
+13 2 Override
checksums
diff --git a/src/northbridge/amd/amdmct/mct_ddr3/mct_d.c b/src/northbridge/amd/amdmct/mct_ddr3/mct_d.c
index 2841b18..4bfb08a 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 a030f71..95d57fc 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 */