Patch set updated for coreboot: intel raminit: properly handle DDR3 DIMMs with address mirroring

[Patrick Rudolph]

Patrick Rudolph ([e-mail]) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/10652

-gerrit

commit 48f5a4d4966823f8ed484f7a1deb49b8b7285971
Author: Patrick Rudolph 
Date:   Wed Jun 24 19:14:53 2015 +0200

intel raminit: properly handle DDR3 DIMMs with address mirroring

Issue observed:
    DDR3 DIMM with address mirroring enabled doesn't work when placed in
    slot 1 and slot 0 is empty. It does work when placed in slot 0 and
    slot 1 is empty.

Test system:
    * Intel IvyBridge
    * Gigabyte GA-B75M-D3H
    * Kingston KVR1066D3N7/4G (address mirroring enabled DIMM)

Problem description:
    The address mirror enable bit is slot-swapped in the DIMM mapping code,
    but none of the remaining code is aware of DIMM mapping. Removing the
    code, that is swapping the mirror enable bit, results in the correct
    behaviour. The DIMM is now working in every slot.

Change-Id: I7a51bbc8d156209449fd67c954930835814a40ee
    Signed-off-by: Patrick Rudolph 
---
 src/northbridge/intel/sandybridge/raminit_native.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/src/northbridge/intel/sandybridge/raminit_native.c b/src/northbridge/intel/sandybridge/raminit_native.c
index a569411..e567cce 100644
--- a/src/northbridge/intel/sandybridge/raminit_native.c
+++ b/src/northbridge/intel/sandybridge/raminit_native.c
@@ -812,7 +812,6 @@ static void dram_timing_regs(ramctr_timing * ctrl)

static void dram_dimm_mapping(dimm_info * info, ramctr_timing * ctrl)
 {
-	int t;
    u32 reg, val32;
    int channel;

@@ -832,11 +831,6 @@ static void dram_dimm_mapping(dimm_info * info, ramctr_timing * ctrl)
    		dimmA = &info->dimm[channel][1];
    		dimmB = &info->dimm[channel][0];
    		reg |= (1 << 16);
-			// swap dimm info
-			t = ctrl->rank_mirror[channel][1];
-			ctrl->rank_mirror[channel][1] =
-			    ctrl->rank_mirror[channel][3];
-			ctrl->rank_mirror[channel][3] = t;
    	}
    	// dimmA
    	if (dimmA && (dimmA->ranks > 0)) {
@@ -1231,6 +1225,9 @@ static void write_mrreg(ramctr_timing * ctrl, int channel, int slotrank,
    printram("MRd: %x <= %x\n", reg, val);

if (ctrl->rank_mirror[channel][slotrank]) {
+		/* DDR3 Rank1 Address mirror
+		 * swap the following pins:
+		 * A3<->A4, A5<->A6, A7<->A8, BA0<->BA1 */
    	reg = ((reg >> 1) & 1) | ((reg << 1) & 2);
    	val = (val & ~0x1f8) | ((val >> 1) & 0xa8)
    	    | ((val & 0xa8) << 1);