google/purin: add DMA coherent region

BUG=none
BRANCH=broadcom-firmware
TEST=boot to depthcharge

Change-Id: Id10437c12e219e07121395abd442d53b3b56c7be
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: f33e9218ca8df1d149761c09253c30837b607433
Original-Signed-off-by: Daisuke Nojiri <dnojiri@chromium.org>
Original-Reviewed-on: https://chrome-internal-review.googlesource.com/204757
Original-Reviewed-by: Julius Werner <jwerner@chromium.org>
Original-Commit-Queue: Daisuke Nojiri <dnojiri@google.com>
Original-Tested-by: Daisuke Nojiri <dnojiri@google.com>
Original-Change-Id: I93def9c326cc8b4fea69078987bddf09d9f2a797
Original-Reviewed-on: https://chromium-review.googlesource.com/256417
Reviewed-on: http://review.coreboot.org/9854
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
diff --git a/src/mainboard/google/purin/Kconfig b/src/mainboard/google/purin/Kconfig
index b9d73f0..0d1965f 100644
--- a/src/mainboard/google/purin/Kconfig
+++ b/src/mainboard/google/purin/Kconfig
@@ -45,16 +45,12 @@
 	string
 	default "Google"
 
-config VBOOT_RAMSTAGE_INDEX
-	hex
-	default 0x3
-
 config BOOT_MEDIA_SPI_BUS
 	int
 	default 0
 
 config DRAM_SIZE_MB
 	int
-	default 1024
+	default 256
 
 endif #  BOARD_GOOGLE_PURIN