[coreboot-gerrit] Change in ...coreboot[master]: soc/intel/cannonlake: Use MEM_CH_SEL to initialize MemorySpdPrts

[Shelley Chen (Code Review)]

Shelley Chen has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/31262

Change subject: soc/intel/cannonlake: Use MEM_CH_SEL to initialize MemorySpdPrts
......................................................................

soc/intel/cannonlake: Use MEM_CH_SEL to initialize MemorySpdPrts

MEM_CH_SEL is used to indicate whether we are on a single or dual
channel device, where MEM_CH_SEL = 1 for single channel skus and
MEM_CH_SEL = 0 for dual channel skus.  Initialize MemorySpdPrt
pointers based on the value read from MEM_CH_SEL, which is read from
GPP_F2.  In the first build, we did not use GPP_F2, so we need to add
an internal pulldown as those early devices were all dual channel
devices.

BUG=b:123062346, b:122959294
BRANCH=None
TEST=Boot into current boards and ensure that we have 2 channels as expected
     Also, verify that GPP_F2 is set to 0.

Change-Id: Ice22b103664187834e255d1359bfd9b51993b5b6
Signed-off-by: Shelley Chen 
---
M src/soc/intel/cannonlake/cnl_memcfg_init.c
1 file changed, 12 insertions(+), 2 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/62/31262/1

diff --git a/src/soc/intel/cannonlake/cnl_memcfg_init.c b/src/soc/intel/cannonlake/cnl_memcfg_init.c
index 4425862..8bd82a6 100644
--- a/src/soc/intel/cannonlake/cnl_memcfg_init.c
+++ b/src/soc/intel/cannonlake/cnl_memcfg_init.c
@@ -15,7 +15,9 @@
 #include <assert.h>
 #include <console/console.h>
 #include <fsp/util.h>
+#include <gpio.h>
 #include <soc/cnl_memcfg_init.h>
+#include <soc/gpio_soc_defs.h>
 #include <spd_bin.h>
 #include <string.h>

@@ -55,8 +57,16 @@
    mem_cfg->MemorySpdDataLen = spd_data_len;
    mem_cfg->MemorySpdPtr00 = spd_data_ptr;

-	/* Use the same spd data for channel 1, Dimm 0 */
-	mem_cfg->MemorySpdPtr10 = mem_cfg->MemorySpdPtr00;
+	/*
+	 * GPP_F2 is the MEM_CH_SEL gpio, which is set to 1 for single
+	 * channel skus and 0 for dual channel skus.
+	 */
+	if (gpio_get(GPP_F2) == 1)
+		mem_cfg->MemorySpdPtr10 = 0;
+	else {
+		/* Use the same spd data for channel 1, Dimm 0 */
+		mem_cfg->MemorySpdPtr10 = mem_cfg->MemorySpdPtr00;
+	}
 }

/*