Fix the ec flash programming script to properly handle errors

When a nonexisting file is specified as the EC image, the ec flash
programming script reports the error, but continues running and
returns zero status (success) after completion.

With this change the exit status on some errors gets communicated to
the caller.

The openocd script is edited to drop the unused parameter of the
flash_lm4() function and the flash_ec script is edited not to require
EC images to be executable.

BRANCH=none
BUG=chrome-os-partner:15610
TEST=manual
   . run flash_ec with nonexisting or nonreadable file as a parameter,
     observe it to report proper return status. Run it with a proper
     image file name and observe it succeed.
   . run the command again, while the device is being programmed enter
     'ctl-c', observe programming stepped but the 'Restoring servo
     settings..." message still showing up.

Change-Id: Iac0b233fe579b0d5a84cf5a9acf85ed8bf10422e
Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/37363
Reviewed-by: Vincent Palatin <vpalatin@chromium.org>

2 files changed, 32 insertions, 23 deletions

diff --git a/chip/lm4/openocd/lm4x_cmds.tcl b/chip/lm4/openocd/lm4x_cmds.tcl
index 00bec7f7b5..056a143512 100644
--- a/chip/lm4/openocd/lm4x_cmds.tcl
+++ b/chip/lm4/openocd/lm4x_cmds.tcl
@@ -6,7 +6,7 @@
 
 # Program internal flash
 
-proc flash_lm4 {path offset size} {
+proc flash_lm4 {path offset} {
 	#set firstsect [expr {$offset / 1024}];
 	#set lastsect [expr {($offset + $size) / 1024 - 1}];
 	reset halt;
@@ -16,19 +16,19 @@ proc flash_lm4 {path offset size} {
 
 # Link proto0 has 128KB flash; proto1+ have 256KB
 proc flash_link { } {
-	flash_lm4 ../../../build/link/ec.bin 0 262144
+	flash_lm4 ../../../build/link/ec.bin 0
 }
 
 proc flash_link_ro { } {
-	flash_lm4 ../../../build/link/ec.RO.flat 0 81920
+	flash_lm4 ../../../build/link/ec.RO.flat 0
 }
 
 proc flash_link_rw { } {
-	flash_lm4 ../../../build/link/ec.RW.bin 81920 81920
+	flash_lm4 ../../../build/link/ec.RW.bin 81920
 }
 
 proc flash_bds { } {
-	flash_lm4 ../../../build/bds/ec.bin 0 262144
+	flash_lm4 ../../../build/bds/ec.bin 0
 }
 
 # Boot a software using internal RAM only
@@ -51,5 +51,5 @@ proc ramboot_bds { } {
 proc flash_emerged_link { } {
 	set firmware_image ../../../../../../chroot/build/link/firmware/ec.bin
 
-	flash_lm4 $firmware_image 0 262144
+	flash_lm4 $firmware_image 0
 }
diff --git a/util/flash_ec b/util/flash_ec
index 417a823fd5..194270d1fc 100755
--- a/util/flash_ec
+++ b/util/flash_ec
@@ -14,6 +14,8 @@ DEFINE_string image "" \
 	"Full pathname of the EC firmware image to flash."
 DEFINE_boolean ro "${FLAGS_FALSE}" \
 	"Write only the read-only partition"
+DEFINE_string offset "0" \
+	"Offset where to program the image from."
 
 # Parse command line
 FLAGS_HELP="usage: $0 [flags]"
@@ -21,6 +23,20 @@ FLAGS "$@" || exit 1
 eval set -- "${FLAGS_ARGV}"
 check_flags_only_and_allow_null_arg "$@" && set --
 
+set -e
+
+cleanup() {
+	if [ -n "${save}" ]; then
+		info "Restoring servo settings..."
+		servo_restore "$save"
+	fi
+
+	# reset the EC
+        dut_control cold_reset:on
+        dut_control cold_reset:off
+}
+trap cleanup EXIT
+
 BOARD=${FLAGS_board}
 BOARD_ROOT=/build/${BOARD}
 
@@ -36,18 +52,18 @@ LOCAL_BUILD=${SRC_ROOT}/platform/ec/build/${BOARD}/${EC_FILE}
 # Find the EC image to use
 function ec_image() {
 	# No image specified on the command line, try default ones
-	if [[ ! -z "${FLAGS_image}" ]] ; then
-		if [ ! -r "${FLAGS_image}" ]; then
-			die "Invalid image path : ${FLAGS_image}"
+	if [[ -n "${FLAGS_image}" ]] ; then
+		if [ -f "${FLAGS_image}" ]; then
+			echo "${FLAGS_image}"
+			return
 		fi
-		echo "${FLAGS_image}"
-		return
+		die "Invalid image path : ${FLAGS_image}"
 	else
-		if [ -x "${LOCAL_BUILD}" ]; then
+		if [ -f "${LOCAL_BUILD}" ]; then
 			echo "${LOCAL_BUILD}"
 			return
 		fi
-		if [ -x "${EMERGE_BUILD}" ]; then
+		if [ -f "${EMERGE_BUILD}" ]; then
 			echo "${EMERGE_BUILD}"
 			return
 		fi
@@ -104,15 +120,15 @@ function flash_daisy() {
 }
 
 function flash_link() {
-	IMG_SIZE=262144
 	OCD_CFG="servo_v2_slower.cfg"
 	OCD_PATH="${SRC_ROOT}/platform/ec/chip/lm4/openocd"
-	OCD_CMDS="init ; flash_lm4 ${IMG} 0 262144 ; exit"
+	OCD_CMDS="init ; flash_lm4 ${IMG} ${FLAGS_offset}; shutdown;"
 
 	dut_control jtag_buf_on_flex_en:on
 	dut_control jtag_buf_en:on
 
-	sudo openocd -s "${OCD_PATH}" -f "${OCD_CFG}" -c "${OCD_CMDS}"
+	sudo openocd -s "${OCD_PATH}" -f "${OCD_CFG}" -c "${OCD_CMDS}" || \
+          die "Failed to program ${IMG}"
 }
 
 IMG="$(ec_image)"
@@ -130,10 +146,3 @@ case "${BOARD}" in
 esac
 
 info "Flashing done."
-
-# Restore servo settings
-servo_restore "$save"
-
-# reset the EC
-dut_control cold_reset:on
-dut_control cold_reset:off