summaryrefslogtreecommitdiff
path: root/src/northbridge
diff options
context:
space:
mode:
authorDan Elkouby <streetwalkermc@gmail.com>2018-04-13 18:47:10 +0300
committerPatrick Georgi <pgeorgi@google.com>2018-04-16 08:46:30 +0000
commitdabebc3716bac1dbe9445dfb2bbbbb833ee21de1 (patch)
tree5cc39ad5a948381b6f76a664332bde6077112ebc /src/northbridge
parent0c024208cdd3cfdfd7689b6fcba1b5c877f550c7 (diff)
downloadcoreboot-dabebc3716bac1dbe9445dfb2bbbbb833ee21de1.tar.xz
nb/intel/sandybridge: support more XMP timings
Tested with a pair of GSkill F3-1866C9-8GSR. This makes sure in particular that we honor the CMD rate requested by the XMP profile. This memory kit needs a CMD rate of 2 to be stable at DDR3-1600 and up, even though it passes training at 1. Also respect requested CWL to match vendor firmware and for a potential increase in performance. The tested kit requests a tighter value than the per-frequency table provides and has shown to be stable using that setting. Change-Id: I634bed764d76345c27f02a2fae5abb2d81b38fd9 Signed-off-by: Dan Elkouby <streetwalkermc@gmail.com> Reviewed-on: https://review.coreboot.org/25664 Reviewed-by: Patrick Rudolph <siro@das-labor.org> Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Diffstat (limited to 'src/northbridge')
-rw-r--r--src/northbridge/intel/sandybridge/raminit_common.c8
-rw-r--r--src/northbridge/intel/sandybridge/raminit_common.h2
-rw-r--r--src/northbridge/intel/sandybridge/raminit_ivy.c5
-rw-r--r--src/northbridge/intel/sandybridge/raminit_sandy.c5
4 files changed, 17 insertions, 3 deletions
diff --git a/src/northbridge/intel/sandybridge/raminit_common.c b/src/northbridge/intel/sandybridge/raminit_common.c
index 0a44220bd6..5f6753fefc 100644
--- a/src/northbridge/intel/sandybridge/raminit_common.c
+++ b/src/northbridge/intel/sandybridge/raminit_common.c
@@ -160,6 +160,8 @@ void dram_find_common_params(ramctr_timing *ctrl)
ctrl->tWTR = MAX(ctrl->tWTR, dimm->tWTR);
ctrl->tRTP = MAX(ctrl->tRTP, dimm->tRTP);
ctrl->tFAW = MAX(ctrl->tFAW, dimm->tFAW);
+ ctrl->tCWL = MAX(ctrl->tCWL, dimm->tCWL);
+ ctrl->tCMD = MAX(ctrl->tCMD, dimm->tCMD);
}
if (!ctrl->cas_supported)
@@ -2350,12 +2352,16 @@ int command_training(ramctr_timing *ctrl)
* will fail in write training.
* Workaround: Skip 1T in dual DIMM mode, that's only
* supported by a few DIMMs.
- * TODO: How to detect "1T" DIMMs ?
+ * Only try 1T mode for XMP DIMMs that request it in dual DIMM
+ * mode.
*
* Single DIMM per channel:
* Try command rate 1T and 2T
*/
cmdrate = ((ctrl->rankmap[channel] & 0x5) == 0x5);
+ if (ctrl->tCMD)
+ /* XMP gives the CMD rate in clock ticks, not ns */
+ cmdrate = MIN(DIV_ROUND_UP(ctrl->tCMD, 256) - 1, 1);
for (; cmdrate < 2; cmdrate++) {
err = try_cmd_stretch(ctrl, channel, cmdrate << 1);
diff --git a/src/northbridge/intel/sandybridge/raminit_common.h b/src/northbridge/intel/sandybridge/raminit_common.h
index ab6e592f07..1f32dcddc4 100644
--- a/src/northbridge/intel/sandybridge/raminit_common.h
+++ b/src/northbridge/intel/sandybridge/raminit_common.h
@@ -94,6 +94,8 @@ typedef struct ramctr_timing_st {
u32 tWTR;
u32 tRTP;
u32 tFAW;
+ u32 tCWL;
+ u32 tCMD;
/* Latencies in terms of clock cycles
* They are saved separately as they are needed for DRAM MRS commands*/
u8 CAS; /* CAS read latency */
diff --git a/src/northbridge/intel/sandybridge/raminit_ivy.c b/src/northbridge/intel/sandybridge/raminit_ivy.c
index 675ac7181c..19dea2f2e1 100644
--- a/src/northbridge/intel/sandybridge/raminit_ivy.c
+++ b/src/northbridge/intel/sandybridge/raminit_ivy.c
@@ -479,7 +479,10 @@ static void dram_timing(ramctr_timing *ctrl)
/* DLL_CONFIG_MDLL_W_TIMER */
ctrl->reg_5064b0 = (128000 / ctrl->tCK) + 3;
- ctrl->CWL = get_CWL(ctrl->tCK);
+ if (ctrl->tCWL)
+ ctrl->CWL = DIV_ROUND_UP(ctrl->tCWL, ctrl->tCK);
+ else
+ ctrl->CWL = get_CWL(ctrl->tCK);
printk(BIOS_DEBUG, "Selected CWL latency : %uT\n", ctrl->CWL);
/* Find tRCD */
diff --git a/src/northbridge/intel/sandybridge/raminit_sandy.c b/src/northbridge/intel/sandybridge/raminit_sandy.c
index 3acc5631a3..99c107ec06 100644
--- a/src/northbridge/intel/sandybridge/raminit_sandy.c
+++ b/src/northbridge/intel/sandybridge/raminit_sandy.c
@@ -251,7 +251,10 @@ static void dram_timing(ramctr_timing *ctrl)
/* DLL_CONFIG_MDLL_W_TIMER */
ctrl->reg_5064b0 = (128000 / ctrl->tCK) + 3;
- ctrl->CWL = get_CWL(ctrl->tCK);
+ if (ctrl->tCWL)
+ ctrl->CWL = DIV_ROUND_UP(ctrl->tCWL, ctrl->tCK);
+ else
+ ctrl->CWL = get_CWL(ctrl->tCK);
printk(BIOS_DEBUG, "Selected CWL latency : %uT\n", ctrl->CWL);
/* Find tRCD */