New patch to review for coreboot: nb/amd_mct_ddr3: Move DRAM MCE sync flood enable to ramstage

[Timothy Pearson]

Timothy Pearson ([e-mail]) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/14192

-gerrit

commit a989e41ec446eb06c8a9074d4087351e30500667
Author: Timothy Pearson 
Date:   Wed Mar 30 13:48:24 2016 -0500

nb/amd_mct_ddr3: Move DRAM MCE sync flood enable to ramstage

Enabling sync flood on DRAM MCE directly after ECC clear can
    lead to a system hang with no way to determine the offending
    DRAM module.  Clear MCEs after ECC setup, but do not enable
    sync flood until NB setup in ramstage to allow time for any
    MCEs to accumulate in the status registers.  Before enabling
    sync flood on MCE, determine if any MCEs were logged during
    ramstage execution and display them on the serial console.

Change-Id: Ibd93801be2eed06d89c8d306c14aef5558dd5a15
    Signed-off-by: Timothy Pearson 
---
 src/northbridge/amd/amdfam10/misc_control.c    | 42 ++++++++++++++++++++++++++
 src/northbridge/amd/amdmct/mct_ddr3/mctecc_d.c | 10 ------
 2 files changed, 42 insertions(+), 10 deletions(-)

diff --git a/src/northbridge/amd/amdfam10/misc_control.c b/src/northbridge/amd/amdfam10/misc_control.c
index 4c65bca..cc415cd 100644
--- a/src/northbridge/amd/amdfam10/misc_control.c
+++ b/src/northbridge/amd/amdfam10/misc_control.c
@@ -29,6 +29,7 @@
 #include <device/pci_ops.h>
 #include <pc80/mc146818rtc.h>
 #include <lib.h>
+#include <cbmem.h>
 #include <cpu/amd/model_10xxx_rev.h>

#include "amdfam10.h"
@@ -136,12 +137,53 @@ static void mcf3_set_resources_fam15h(device_t dev)
 static void misc_control_init(struct device *dev)
 {
    uint32_t dword;
+	uint8_t node;
+	uint8_t slot;
    uint8_t nvram;
+	uint8_t dimm_present;
    uint8_t boost_limit;
    uint8_t current_boost;

printk(BIOS_DEBUG, "NB: Function 3 Misc Control.. ");

+	/* Restore DRAM MCA registers */
+	struct amdmct_memory_info *mem_info;
+	mem_info = cbmem_find(CBMEM_ID_AMDMCT_MEMINFO);
+	if (mem_info) {
+		node = PCI_SLOT(dev->path.pci.devfn) - 0x18;
+
+		/* Check node for installed DIMMs */
+		dimm_present = 0;
+
+		/* Check all slots for installed DIMMs */
+		for (slot = 0; slot < MAX_DIMMS_SUPPORTED; slot++) {
+			if (mem_info->dct_stat[node].DIMMPresent & (1 << slot)) {
+				dimm_present = 1;
+				break;
+			}
+		}
+
+		if (dimm_present) {
+			uint32_t mc4_status_high = pci_read_config32(dev, 0x4c);
+			uint32_t mc4_status_low = pci_read_config32(dev, 0x48);
+			if (mc4_status_high != 0) {
+				printk(BIOS_WARNING, "WARNING: MC4 Machine Check Exception detected on node %d!\n"
+					"Signature: %08x%08x\n", node, mc4_status_high, mc4_status_low);
+			}
+
+			/* Clear MC4 error status */
+			pci_write_config32(dev, 0x48, 0x0);
+			pci_write_config32(dev, 0x4c, 0x0);
+
+			if (mem_info->dct_stat[node].mca_config_backed_up) {
+				dword = pci_read_config32(dev, 0x44);
+				dword |= (mem_info->dct_stat[node].sync_flood_on_dram_err & 0x1) << 30;
+				dword |= (mem_info->dct_stat[node].sync_flood_on_any_uc_err & 0x1) << 21;
+				pci_write_config32(dev, 0x44, dword);
+			}
+		}
+	}
+
    /* Disable Machine checks from Invalid Locations.
     * This is needed for PC backwards compatibility.
     */
diff --git a/src/northbridge/amd/amdmct/mct_ddr3/mctecc_d.c b/src/northbridge/amd/amdmct/mct_ddr3/mctecc_d.c
index 07eb0bd..1077cb8 100644
--- a/src/northbridge/amd/amdmct/mct_ddr3/mctecc_d.c
+++ b/src/northbridge/amd/amdmct/mct_ddr3/mctecc_d.c
@@ -84,8 +84,6 @@ u8 ECCInit_D(struct MCTStatStruc *pMCTstat, struct DCTStatStruc *pDCTstatA)
    u32 val;
    u16 nvbits;

-	uint32_t dword;
-
    mctHookBeforeECC();

/* Construct these booleans, based on setup options, for easy handling
@@ -266,14 +264,6 @@ u8 ECCInit_D(struct MCTStatStruc *pMCTstat, struct DCTStatStruc *pDCTstatA)
    			/* Clear MC4 error status */
    			pci_write_config32(pDCTstat->dev_nbmisc, 0x48, 0x0);
    			pci_write_config32(pDCTstat->dev_nbmisc, 0x4c, 0x0);
-
-				/* Restore previous MCA error handling settings */
-				if (pDCTstat->mca_config_backed_up) {
-					dword = Get_NB32(pDCTstat->dev_nbmisc, 0x44);
-					dword |= (pDCTstat->sync_flood_on_dram_err & 0x1) << 30;
-					dword |= (pDCTstat->sync_flood_on_any_uc_err & 0x1) << 21;
-					Set_NB32(pDCTstat->dev_nbmisc, 0x44, dword);
-				}
    		}
    	}
    }