lib: Add VbExDisplaySetDimension.

For displaying GBB images on panels with different dimension, X86 has VESA mode
and VBIOS to scale automatically but ARM does not have such mode settings. If we
install a larger panel on ARM platforms, current firmware will render the
screens in left-top corner and leave black borders in right-bottom corner.

To render images correctly, vboot library has to send out the expected dimension
(similar to the VESA mode) so display provider can scale or shift images.

BUG=chrome-os-partner:28494
TEST=emerge-nyan vboot_reference
CQ-DEPEND=CL:199051,CL:199045
BRANCH=none

Change-Id: I6d60f755ca2bcbd3135631d7624a8a4a4cff68b1
Reviewed-on: https://chromium-review.googlesource.com/199043
Reviewed-by: Bill Richardson <wfrichar@chromium.org>
Tested-by: Hung-Te Lin <hungte@chromium.org>
Commit-Queue: Hung-Te Lin <hungte@chromium.org>

3 files changed, 30 insertions, 0 deletions

diff --git a/firmware/include/vboot_api.h b/firmware/include/vboot_api.h
index 92b9411d..1561defe 100644
--- a/firmware/include/vboot_api.h
+++ b/firmware/include/vboot_api.h
@@ -658,6 +658,15 @@ VbError_t VbExDisplayInit(uint32_t *width, uint32_t *height);
 VbError_t VbExDisplayBacklight(uint8_t enable);
 
 /**
+ * Sets the logical dimension to display.
+ *
+ * If the physical display is larger or smaller than given dimension, display
+ * provider may decide to scale or shift images (from VbExDisplayImage)to proper
+ * location.
+ */
+VbError_t VbExDisplaySetDimension(uint32_t width, uint32_t height);
+
+/**
  * Display a predefined screen; see VB_SCREEN_* for valid screens.
  *
  * This is a backup method of screen display, intended for use if the GBB does
diff --git a/firmware/lib/vboot_display.c b/firmware/lib/vboot_display.c
index 910c60a0..669c4e8d 100644
--- a/firmware/lib/vboot_display.c
+++ b/firmware/lib/vboot_display.c
@@ -231,6 +231,22 @@ VbError_t VbDisplayScreenFromGBB(VbCommonParams *cparams, uint32_t screen,
 
 		switch(image_info.format) {
 		case FORMAT_BMP:
+			if (i == 0) {
+				/**
+				 * In current version GBB bitmaps, first image
+				 * is always the background.
+				 */
+				ret = VbExDisplaySetDimension(
+						image_info.width,
+						image_info.height);
+				if (!ret) {
+					VBDEBUG(("VbExDisplaySetDimension"
+						 "(%d,%d): failed.\n",
+						 image_info.width,
+						 image_info.height));
+				}
+			}
+
 			retval = VbExDisplayImage(layout.images[i].x,
 						  layout.images[i].y,
 						  fullimage, inoutsize);
diff --git a/firmware/stub/vboot_api_stub.c b/firmware/stub/vboot_api_stub.c
index 913cac15..b11a7fe1 100644
--- a/firmware/stub/vboot_api_stub.c
+++ b/firmware/stub/vboot_api_stub.c
@@ -36,6 +36,11 @@ VbError_t VbExDisplayBacklight(uint8_t enable)
 	return VBERROR_SUCCESS;
 }
 
+VbError_t VbExDisplaySetDimension(uint32_t width, uint32_t height)
+{
+	return VBERROR_SUCCESS;
+}
+
 VbError_t VbExDisplayScreen(uint32_t screen_type)
 {
 	return VBERROR_SUCCESS;