Change in coreboot[master]: mb/google/poppy/variants/nautilus: Set CABC_EN to GPO high before EDP...

[Seunghwan Kim (Code Review)]

Seunghwan Kim has uploaded this change for review. ( https://review.coreboot.org/27773

Change subject: mb/google/poppy/variants/nautilus: Set CABC_EN to GPO high before EDP power on
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mb/google/poppy/variants/nautilus: Set CABC_EN to GPO high before EDP power on

If GPP_E22(CABC_EN) remained floating GPI(SoC default) at V3.3_DX_EDP on,
it may cause damage on the GPIO pad.

To prevent, we would set this pad to GPO on romstage before EDP power on.

Since we need to cover all systems in market, I put it into romstage
instead of early_gpio_table.

BUG=b:111860510
BRANCH=poppy
TEST=Verified CABC_EN is set to GPO high 5ms before EDP power on

Change-Id: I34e2fe86329a88eb05e0ea3c6beac6a64754b41e
Signed-off-by: Seunghwan Kim 
---
M src/mainboard/google/poppy/variants/nautilus/memory.c
1 file changed, 5 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/73/27773/1

diff --git a/src/mainboard/google/poppy/variants/nautilus/memory.c b/src/mainboard/google/poppy/variants/nautilus/memory.c
index dc845bc..bf2accf 100644
--- a/src/mainboard/google/poppy/variants/nautilus/memory.c
+++ b/src/mainboard/google/poppy/variants/nautilus/memory.c
@@ -14,6 +14,7 @@
  */

#include <baseboard/variants.h>
+#include <gpio.h>

/* DQ byte map */
 static const u8 dq_map[][12] = {
@@ -46,4 +47,8 @@
    p->rcomp_resistor_size = sizeof(rcomp_resistor);
    p->rcomp_target = rcomp_target;
    p->rcomp_target_size = sizeof(rcomp_target);
+
+	/* Ensure GPP_E22(CABC_EN) is set to GPO before enabling V3.3_DX_EDP.
+	 * If it is remained floating GPI, it may cause damage on the pad.*/
+	gpio_output(GPP_E22, 1);
 }