[coreboot-gerrit] Change in coreboot[master]: drivers/vpd: add VPD region VPD_RW_THEN_RO

[Patrick Georgi (Code Review)]

Patrick Georgi has submitted this change. ( https://review.coreboot.org/c/coreboot/+/41732 )

Change subject: drivers/vpd: add VPD region VPD_RW_THEN_RO
......................................................................

drivers/vpd: add VPD region VPD_RW_THEN_RO

This change is based on the concept that system user's (overwrite)
settings are held in VPD_RW region, while system owner's (default)
settings are held in VPD_RO region.

Add VPD_RW_THEN_RO region type, so that VPD_RW region is searched
first to get overwrite setting, otherwise VPD_RO region is searched
to get default setting.

Signed-off-by: Jonathan Zhang 
Change-Id: Icd7cbd9c3fb2a6b02fc417ad45d7d22ca6795457
Reviewed-on: https://review.coreboot.org/c/coreboot/+/41732
Tested-by: build bot (Jenkins) 
Reviewed-by: Hung-Te Lin 
---
M src/drivers/vpd/vpd.c
M src/drivers/vpd/vpd.h
2 files changed, 10 insertions(+), 5 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Hung-Te Lin: Looks good to me, approved

diff --git a/src/drivers/vpd/vpd.c b/src/drivers/vpd/vpd.c
index f5ac81e..c332a6e 100644
--- a/src/drivers/vpd/vpd.c
+++ b/src/drivers/vpd/vpd.c
@@ -209,10 +209,14 @@

init_vpd_rdevs();

-	if (region != VPD_RW)
+	if (region == VPD_RW_THEN_RO)
+		vpd_find_in(&rw_vpd, &arg);
+
+	if (!arg.matched && (region == VPD_RO || region == VPD_RO_THEN_RW ||
+			region == VPD_RW_THEN_RO))
    	vpd_find_in(&ro_vpd, &arg);

-	if (!arg.matched && region != VPD_RO)
+	if (!arg.matched && (region == VPD_RW || region == VPD_RO_THEN_RW))
    	vpd_find_in(&rw_vpd, &arg);

if (!arg.matched)
diff --git a/src/drivers/vpd/vpd.h b/src/drivers/vpd/vpd.h
index df7711a..25e0aed 100644
--- a/src/drivers/vpd/vpd.h
+++ b/src/drivers/vpd/vpd.h
@@ -8,9 +8,10 @@
 #define GOOGLE_VPD_2_0_OFFSET 0x600

enum vpd_region {
-	VPD_RO_THEN_RW = 0,
-	VPD_RO = 1,
-	VPD_RW = 2
+	VPD_RO,
+	VPD_RW,
+	VPD_RO_THEN_RW,
+	VPD_RW_THEN_RO
 };

/*