[coreboot-gerrit] Patch set updated for coreboot: db9f37c armv7/exynos: Fix and remove memory reset workarounds

[Patrick Georgi]

Patrick Georgi ([e-mail]) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/4433

-gerrit

commit db9f37cebf202a79835fb849686637de712721c3
Author: Hung-Te Lin 
Date:   Tue Aug 6 10:48:48 2013 +0800

armv7/exynos: Fix and remove memory reset workarounds

The memory corruption problem in Exynos suspend/resume process is caused by two
    things together: PHY_RESET and MRS command.

After stop sending MRS on resume, we can now remove the workaround of skipping
    PHY_RESET.

Change-Id: I64acc27c1d2bb549ae6ad7d32ecda94b0355972c
    Reviewed-on: https://gerrit.chromium.org/gerrit/64736
    Tested-by: Hung-Te Lin 
    Reviewed-by: David Hendricks 
    Commit-Queue: Hung-Te Lin 
---
 src/cpu/samsung/exynos5250/dmc_init_ddr3.c | 10 ++++++++--
 src/cpu/samsung/exynos5420/dmc_init_ddr3.c | 12 +++++++++---
 src/mainboard/google/snow/romstage.c       |  7 -------
 3 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/src/cpu/samsung/exynos5250/dmc_init_ddr3.c b/src/cpu/samsung/exynos5250/dmc_init_ddr3.c
index e3d46ab..f2c228d 100644
--- a/src/cpu/samsung/exynos5250/dmc_init_ddr3.c
+++ b/src/cpu/samsung/exynos5250/dmc_init_ddr3.c
@@ -158,8 +158,14 @@ int ddr3_mem_ctrl_init(struct mem_timings *mem, unsigned long mem_iv_size,
    /* Send PALL command */
    dmc_config_prech(mem, dmc);

-	/* Send NOP, MRS and ZQINIT commands */
-	dmc_config_mrs(mem, dmc);
+	if (mem_reset) {
+		/* Send NOP, MRS and ZQINIT commands.
+		 * Sending MRS command will reset the DRAM. We should not be
+		 * reseting the DRAM after resume, this will lead to memory
+		 * corruption as DRAM content is lost after DRAM reset
+		 */
+		dmc_config_mrs(mem, dmc);
+	}

if (mem->gate_leveling_enable) {
    	val = PHY_CON0_RESET_VAL;
diff --git a/src/cpu/samsung/exynos5420/dmc_init_ddr3.c b/src/cpu/samsung/exynos5420/dmc_init_ddr3.c
index 74ee7e9..ebfe1e1 100644
--- a/src/cpu/samsung/exynos5420/dmc_init_ddr3.c
+++ b/src/cpu/samsung/exynos5420/dmc_init_ddr3.c
@@ -184,9 +184,15 @@ int ddr3_mem_ctrl_init(struct mem_timings *mem, int interleave_size, int reset)
    writel(mem->timing_power, &drex0->timingpower);
    writel(mem->timing_power, &drex1->timingpower);

-	/* Send NOP, MRS and ZQINIT commands */
-	dmc_config_mrs(mem, drex0);
-	dmc_config_mrs(mem, drex1);
+	/* Send NOP, MRS and ZQINIT commands.
+	 * Sending MRS command will reset the DRAM. We should not be
+	 * reseting the DRAM after resume, this will lead to memory
+	 * corruption as DRAM content is lost after DRAM reset.
+	 */
+	if (reset) {
+		dmc_config_mrs(mem, drex0);
+		dmc_config_mrs(mem, drex1);
+	}

if (mem->gate_leveling_enable) {

diff --git a/src/mainboard/google/snow/romstage.c b/src/mainboard/google/snow/romstage.c
index f69fb1f..92fa21e 100644
--- a/src/mainboard/google/snow/romstage.c
+++ b/src/mainboard/google/snow/romstage.c
@@ -141,13 +141,6 @@ static void setup_memory(struct mem_timings *mem, int is_resume)
           mem->mpll_mdiv,
           mem->frequency_mhz);

-	/* FIXME Currently memory initialization with mem_reset on normal boot
-	 * will cause resume to fail (even if we don't do mem_reset on resume),
-	 * and the workaround is to temporarily always enable "is_resume".
-	 * This should be removed when the root cause of resume issue is found.
-	 */
-	is_resume = 1;
-
    if (ddr3_mem_ctrl_init(mem, DMC_INTERLEAVE_SIZE, !is_resume)) {
    	die("Failed to initialize memory controller.\n");
    }