New patch to review for coreboot: soc/intel/apollolake: Disable Periodic Retraining per-SKU

[Andrey Petrov]

Andrey Petrov ([e-mail]) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/16320

-gerrit

commit 41ab84594430929f572a464c889f9600fb9e3a1e
Author: Andrey Petrov 
Date:   Thu Aug 25 11:06:08 2016 -0700

soc/intel/apollolake: Disable Periodic Retraining per-SKU

Certain LPDDR4 models have some HW issues that can be workarounded
    by turning off Periodic Retraining feature in the memory controller.
    Add option to disable PR per SKU.

BUG=chrome-os-partner:55466
    TEST=not tested yet

Change-Id: Ie7aa79586665f6d3a7edd854a9eef07e6a1b2ab8
    Signed-off-by: Andrey Petrov 
---
 src/mainboard/google/reef/romstage.c           | 1 +
 src/soc/intel/apollolake/include/soc/meminit.h | 2 ++
 src/soc/intel/apollolake/meminit.c             | 2 ++
 3 files changed, 5 insertions(+)

diff --git a/src/mainboard/google/reef/romstage.c b/src/mainboard/google/reef/romstage.c
index e8d8e16..a963095 100644
--- a/src/mainboard/google/reef/romstage.c
+++ b/src/mainboard/google/reef/romstage.c
@@ -110,6 +110,7 @@ static const struct lpddr4_sku skus[] = {
    	.ch0_rank_density = LP4_8Gb_DENSITY,
    	.ch1_rank_density = LP4_8Gb_DENSITY,
    	.part_num = "MT53B256M32D1NP",
+		.per_retrn_dis = 1,
    },
    /* K4F8E304HB-MGCH - both logical channels */
    [PROTO_SKU] = {
diff --git a/src/soc/intel/apollolake/include/soc/meminit.h b/src/soc/intel/apollolake/include/soc/meminit.h
index c115c4a..0f95392 100644
--- a/src/soc/intel/apollolake/include/soc/meminit.h
+++ b/src/soc/intel/apollolake/include/soc/meminit.h
@@ -102,6 +102,8 @@ struct lpddr4_sku {
    int ch0_dual_rank;
    int ch1_dual_rank;
    const char *part_num;
+	/* Disable periodic retraining. */
+	bool per_retrn_dis;
 };

struct lpddr4_cfg {
diff --git a/src/soc/intel/apollolake/meminit.c b/src/soc/intel/apollolake/meminit.c
index 03e9ac4..dc770d8 100644
--- a/src/soc/intel/apollolake/meminit.c
+++ b/src/soc/intel/apollolake/meminit.c
@@ -254,6 +254,8 @@ void meminit_lpddr4_by_sku(struct FSP_M_CONFIG *cfg,
    					sku->ch1_dual_rank,
    					lpcfg->swizzle_config);
    }
+
+	cfg->PeriodicRetrainingDisable = sku->per_retrn_dis;
 }

void save_lpddr4_dimm_info(const struct lpddr4_cfg *lp4cfg, size_t mem_sku)