tegra124: Skip display init when vboot says we don't need it.

If EFS is enabled and vboot didn't tell us it's going to use the display, we
can skip initializing it and save some boot time.

BUG=chrome-os-partner:27094
TEST=Built and booted on nyan without EFS in recovery mode and normal mode.
Built and booted on nyan with EFS in recovery mode and normal mode. Verified
that in normal mode with EFS the display initialization was skipped and boot
time was essentially the same as when display initialization was simply
commented out.
BRANCH=None

Original-Change-Id: I1e2842b57a38061f40514407c8fab1e38b75be80
Original-Signed-off-by: Gabe Black <gabeblack@google.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/192544
Original-Reviewed-by: Tom Warren <twarren@nvidia.com>
Original-Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Original-Commit-Queue: Gabe Black <gabeblack@chromium.org>
Original-Tested-by: Gabe Black <gabeblack@chromium.org>
(cherry picked from commit a672d18c3570e6991a1c1c0089697112a4cd71d0)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>

Change-Id: I95e8bd7a447876174305f755cc632365ed6f5a30
Reviewed-on: http://review.coreboot.org/7734
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Tested-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

3 files changed, 19 insertions, 1 deletions

diff --git a/src/soc/nvidia/tegra124/soc.c b/src/soc/nvidia/tegra124/soc.c
index 08a4cf8e13..48e50bdc3f 100644
--- a/src/soc/nvidia/tegra124/soc.c
+++ b/src/soc/nvidia/tegra124/soc.c
@@ -26,6 +26,7 @@
 #include <soc/nvidia/tegra124/sdram.h>
 #include "chip.h"
 #include <soc/display.h>
+#include <vendorcode/google/chromeos/chromeos.h>
 
 /* this sucks, but for now, fb size/location are hardcoded.
  * Will break if we get 2. Sigh.
@@ -50,7 +51,10 @@ static void soc_enable(device_t dev)
 
 static void soc_init(device_t dev)
 {
-	display_startup(dev);
+	if (vboot_skip_display_init())
+		printk(BIOS_INFO, "Skipping display init.\n");
+	else
+		display_startup(dev);
 	printk(BIOS_INFO, "CPU: Tegra124\n");
 }
 
diff --git a/src/vendorcode/google/chromeos/chromeos.h b/src/vendorcode/google/chromeos/chromeos.h
index c162891fdd..6e3b2dacf1 100644
--- a/src/vendorcode/google/chromeos/chromeos.h
+++ b/src/vendorcode/google/chromeos/chromeos.h
@@ -47,6 +47,7 @@ void *vboot_get_region(uintptr_t offset_addr, size_t size, void *dest);
 int vboot_get_handoff_info(void **addr, uint32_t *size);
 int vboot_enable_developer(void);
 int vboot_enable_recovery(void);
+int vboot_skip_display_init(void);
 #else
 static inline void vboot_verify_firmware(struct romstage_handoff *h) {}
 static inline void *vboot_get_payload(int *len) { return NULL; }
@@ -54,6 +55,7 @@ static inline int vboot_get_handoff_info(void **addr, uint32_t *size)
 {
 	return -1;
 }
+static inline int vboot_skip_display_init(void) { return 0; }
 #endif
 
 #include "gnvs.h"
diff --git a/src/vendorcode/google/chromeos/vboot_handoff.c b/src/vendorcode/google/chromeos/vboot_handoff.c
index c3c5a138d7..71ac5cdb48 100644
--- a/src/vendorcode/google/chromeos/vboot_handoff.c
+++ b/src/vendorcode/google/chromeos/vboot_handoff.c
@@ -54,6 +54,18 @@ int vboot_enable_recovery(void)
 	return !!(vbho->init_params.out_flags & VB_INIT_OUT_ENABLE_RECOVERY);
 }
 
+int vboot_skip_display_init(void)
+{
+	struct vboot_handoff *vbho;
+
+	vbho = cbmem_find(CBMEM_ID_VBOOT_HANDOFF);
+
+	if (vbho == NULL)
+		return 0;
+
+	return !(vbho->init_params.out_flags & VB_INIT_OUT_ENABLE_DISPLAY);
+}
+
 void *vboot_get_region(uintptr_t offset_addr, size_t size, void *dest)
 {
       if (IS_ENABLED(CONFIG_SPI_FLASH_MEMORY_MAPPED)) {