vboot2: implement vb2ex_read_resource

TEST=Built with VBOOT2_VERIFY_FIRMWARE on/off. Booted Nyan Blaze.
BUG=None
BRANCH=none
Signed-off-by: Daisuke Nojiri <dnojiri@chromium.org>

Original-Change-Id: I633f9dddbf8b2f25797aacc246bcebaafb02bea4
Original-Reviewed-on: https://chromium-review.googlesource.com/206063
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Original-Tested-by: Daisuke Nojiri <dnojiri@chromium.org>
Original-Commit-Queue: Daisuke Nojiri <dnojiri@chromium.org>
(cherry picked from commit 1f215672de31847cc647e83d2c04633b7f8dfa33)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>

Change-Id: I57f449b052132b300f7bca4351871c539a7a8694
Reviewed-on: http://review.coreboot.org/8161
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Tested-by: build bot (Jenkins)

1 files changed, 37 insertions, 18 deletions

diff --git a/src/vendorcode/google/chromeos/vboot_main.c b/src/vendorcode/google/chromeos/vboot_main.c
index 9779d35eea..907afd73b3 100644
--- a/src/vendorcode/google/chromeos/vboot_main.c
+++ b/src/vendorcode/google/chromeos/vboot_main.c
@@ -31,6 +31,23 @@ struct vboot_region {
 	int32_t size;
 };
 
+static void locate_region(const char *name, struct vboot_region *region)
+{
+	region->size = find_fmap_entry(name, (void **)&region->offset_addr);
+	VBDEBUG("Located %s @%x\n", name, region->offset_addr);
+}
+
+static int is_slot_a(struct vb2_context *ctx)
+{
+	return !(ctx->flags & VB2_CONTEXT_FW_SLOT_B);
+}
+
+static int in_ro(void)
+{
+	/* TODO: Implement */
+	return 1;
+}
+
 /* exports */
 
 void vb2ex_printf(const char *func, const char *fmt, ...)
@@ -57,27 +74,29 @@ int vb2ex_read_resource(struct vb2_context *ctx,
 			void *buf,
 			uint32_t size)
 {
-	VBDEBUG("Reading resource\n");
-	return VB2_ERROR_UNKNOWN;
-}
+	struct vboot_region region;
+
+	switch (index) {
+	case VB2_RES_GBB:
+		locate_region("GBB", &region);
+		break;
+	case VB2_RES_FW_VBLOCK:
+		if (is_slot_a(ctx))
+			locate_region("VBLOCK_A", &region);
+		else
+			locate_region("VBLOCK_B", &region);
+		break;
+	default:
+		return VB2_ERROR_EX_READ_RESOURCE_INDEX;
+	}
 
-/* locals */
+	if (offset + size > region.size)
+		return VB2_ERROR_EX_READ_RESOURCE_SIZE;
 
-static void locate_region(const char *name, struct vboot_region *region)
-{
-	region->size = find_fmap_entry(name, (void **)&region->offset_addr);
-	VBDEBUG("Located %s @%x\n", name, region->offset_addr);
-}
+	if (vboot_get_region(region.offset_addr + offset, size, buf) == NULL)
+		return VB2_ERROR_UNKNOWN;
 
-static int is_slot_a(struct vb2_context *ctx)
-{
-	return !(ctx->flags & VB2_CONTEXT_FW_SLOT_B);
-}
-
-static int in_ro(void)
-{
-	/* TODO: Implement */
-	return 1;
+	return VB2_SUCCESS;
 }
 
 static void reboot(void)