[S] Change in coreboot[main]: nb/intel/sandybridge: Add Kconfig to set default IGD allocation

[Matt DeVillier (Code Review)]

Matt DeVillier has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/84225?usp=email )

Change subject: nb/intel/sandybridge: Add Kconfig to set default IGD allocation
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nb/intel/sandybridge: Add Kconfig to set default IGD allocation

Add a Kconfig choice to select the default IGD memory allocation, for
users/ boards which do not use an option table to set it.

TEST=build/boot google/link, verify IGD size changes with selection.

Change-Id: I83d57cf4657cfccbb21416c5da05eeff9e95a44f
Signed-off-by: Matt DeVillier 
---
M src/northbridge/intel/sandybridge/Kconfig
M src/northbridge/intel/sandybridge/early_init.c
2 files changed, 31 insertions(+), 2 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/25/84225/1

diff --git a/src/northbridge/intel/sandybridge/Kconfig b/src/northbridge/intel/sandybridge/Kconfig
index fa40b06..7c8dba3 100644
--- a/src/northbridge/intel/sandybridge/Kconfig
+++ b/src/northbridge/intel/sandybridge/Kconfig
@@ -180,4 +180,32 @@
 config PRERAM_CBFS_CACHE_SIZE
    default 0x0

+choice
+	prompt "Default IGD Memory Allocation"
+	default IGD_DEFAULT_SIZE_32MB
+	help
+	  The amount of system memory allocated for the integrated GPU if not
+	  set via a (CMOS-backed) option table.
+
+config IGD_DEFAULT_SIZE_32MB
+	bool "32MB"
+
+config IGD_DEFAULT_SIZE_64MB
+	bool "64MB"
+
+config IGD_DEFAULT_SIZE_96MB
+	bool "96MB"
+
+config IGD_DEFAULT_SIZE_128MB
+	bool "128MB"
+
+endchoice
+
+config IGD_DEFAULT_INT_VALUE
+	int
+	default 0 if IGD_DEFAULT_SIZE_32MB
+	default 1 if IGD_DEFAULT_SIZE_64MB
+	default 2 if IGD_DEFAULT_SIZE_96MB
+	default 3 if IGD_DEFAULT_SIZE_128MB
+
 endif
diff --git a/src/northbridge/intel/sandybridge/early_init.c b/src/northbridge/intel/sandybridge/early_init.c
index a5ebf9d..60798f0 100644
--- a/src/northbridge/intel/sandybridge/early_init.c
+++ b/src/northbridge/intel/sandybridge/early_init.c
@@ -86,9 +86,10 @@

printk(BIOS_DEBUG, "Initializing Graphics...\n");

-	/* Fall back to 32 MiB for IGD memory by setting GGC[7:3] = 1 */
-	gfxsize = get_uint_option("gfx_uma_size", 0);
+	/* Fall back to IGD_DEFAULT_INT_VALUE for IGD memory */
+	gfxsize = get_uint_option("gfx_uma_size", IGD_DEFAULT_INT_VALUE);

+	/* Program IGD memory allocation by setting GGC[7:3] */
    reg16 = pci_read_config16(HOST_BRIDGE, GGC);
    reg16 &= ~0x00f8;
    reg16 |= (gfxsize + 1) << 3;