futility: update: Add --programmer to override flashrom programmer for servo

Many developers need to reflash or update firmware using servo, and the
firmware logic has been complicated enough that simply calling
'flashrom -w image.bin -p $SERVO' will usually destroy many important
settings, for example HWID, VPD, and other data provisioned in factory.

It should be more convenient if we can use 'futility update' against
servo. The '--programmer' provides first step - to override the flashrom
programmer so we can read and write via special programmer (like servo).

With this change, developers can reflash using:

 futility -p $SERVO -i $IMAGE --force --wp 0

BRANCH=None
BUG=b:116326638
TEST=make futil; sudo tests/futility/run_test_scripts.sh $(pwd)/build/futility

Change-Id: Iad4819ff8258086e1abb58fefd462d94050754d0
Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1239817
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Reviewed-by: Randall Spangler <rspangler@chromium.org>

2 files changed, 34 insertions, 7 deletions

diff --git a/futility/cmd_update.c b/futility/cmd_update.c
index 6bc68524..19d118c0 100644
--- a/futility/cmd_update.c
+++ b/futility/cmd_update.c
@@ -1777,6 +1777,7 @@ static struct option const long_opts[] = {
 	{"mode", 1, NULL, 'm'},
 	{"factory", 0, NULL, 'Y'},
 	{"force", 0, NULL, 'F'},
+	{"programmer", 1, NULL, 'p'},
 	{"wp", 1, NULL, 'W'},
 	{"emulate", 1, NULL, 'E'},
 	{"sys_props", 1, NULL, 'S'},
@@ -1786,7 +1787,7 @@ static struct option const long_opts[] = {
 	{NULL, 0, NULL, 0},
 };
 
-static const char * const short_opts = "hi:e:tm:dv";
+static const char * const short_opts = "hi:e:tm:p:dv";
 
 static void print_help(int argc, char *argv[])
 {
@@ -1797,6 +1798,7 @@ static void print_help(int argc, char *argv[])
 		"-e, --ec_image=FILE \tEC firmware image (i.e, ec.bin)\n"
 		"    --pd_image=FILE \tPD firmware image (i.e, pd.bin)\n"
 		"-t, --try           \tTry A/B update on reboot if possible\n"
+		"-p, --programmer=PRG\tChange AP (host) flashrom programmer\n"
 		"    --quirks=LIST   \tSpecify the quirks to apply\n"
 		"    --list-quirks   \tPrint all available quirks\n"
 		"\n"
@@ -1817,8 +1819,9 @@ static void print_help(int argc, char *argv[])
 
 static int do_update(int argc, char *argv[])
 {
-	int i, r, errorcnt = 0;
+	int i, r, single_image = 0, errorcnt = 0;
 	int check_wp_disabled = 0;
+	char *opt_programmer = NULL;
 	struct updater_config cfg = {
 		.image = { .programmer = PROG_HOST, },
 		.image_current = { .programmer = PROG_HOST, },
@@ -1907,6 +1910,9 @@ static int do_update(int argc, char *argv[])
 			cfg.emulation = strdup(optarg);
 			DEBUG("Emulate with file: %s", cfg.emulation);
 			break;
+		case 'p':
+			opt_programmer = strdup(optarg);
+			break;
 		case 'F':
 			cfg.force_update = 1;
 			break;
@@ -1943,14 +1949,20 @@ static int do_update(int argc, char *argv[])
 		errorcnt++;
 		Error("Unexpected arguments.\n");
 	}
+	if (opt_programmer) {
+		single_image = 1;
+		cfg.image.programmer = opt_programmer;
+		cfg.image_current.programmer = opt_programmer;
+		DEBUG("AP (host) programmer changed to %s.", opt_programmer);
+	}
 	if (cfg.emulation) {
-		if (cfg.ec_image.data || cfg.pd_image.data) {
-			errorcnt++;
-			Error("EC/PD images are not supported in emulation.\n");
-		}
-		/* We only support emulating AP firmware. */
+		single_image = 1;
 		errorcnt += load_image(cfg.emulation, &cfg.image_current);
 	}
+	if (single_image && (cfg.ec_image.data || cfg.pd_image.data)) {
+		errorcnt++;
+		Error("EC/PD images are not supported in current mode.\n");
+	}
 	if (check_wp_disabled && is_write_protection_enabled(&cfg)) {
 		errorcnt++;
 		Error("Factory mode needs WP disabled.\n");
@@ -1967,6 +1979,11 @@ static int do_update(int argc, char *argv[])
 	       errorcnt ? "FAILED": "DONE",
 	       errorcnt ? "stopped due to error" : "exited successfully");
 	unload_updater_config(&cfg);
+	if (opt_programmer) {
+		cfg.image.programmer = PROG_HOST;
+		cfg.image_current.programmer = PROG_HOST;
+		free(opt_programmer);
+	}
 	remove_all_temp_files();
 	return !!errorcnt;
 }
diff --git a/tests/futility/test_update.sh b/tests/futility/test_update.sh
index c5615f0f..1b80e2e5 100755
--- a/tests/futility/test_update.sh
+++ b/tests/futility/test_update.sh
@@ -277,3 +277,13 @@ test_update "Full update (--quirks min_platform_version)" \
 	"${FROM_IMAGE}" "${TMP}.expected.full" \
 	--quirks min_platform_version=3 \
 	-i "${TO_IMAGE}" --wp=0 --sys_props 0,0x10001,1,3
+
+# Test special programmer
+if type flashrom >/dev/null 2>&1; then
+	echo "TEST: Full update (dummy programmer)"
+	cp -f "${FROM_IMAGE}" "${TMP}.emu"
+	sudo "${FUTILITY}" update --programmer \
+		dummy:emulate=VARIABLE_SIZE,image=${TMP}.emu,size=8388608 \
+		-i "${TO_IMAGE}" --wp=0 --sys_props 0,0x10001,1,3 >&2
+	cmp "${TMP}.emu" "${TMP}.expected.full"
+fi