rollback: Add host command to query rollback information

Rollback id will be useful to check that the secret has actually
been wiped. Min rollback version and RW rollback version might
be useful in the future.

BRANCH=nocturne
BUG=b:115733483
TEST=ectool --name=cros_fp rollbackinfo
=> Rollback block id:    X
ectool --name=cros_fp reboot_ec; sleep 0.5; \
   ectool --name=cros_fp rwsigaction abort && \
   ectool --name=cros_fp addentropy reset && \
   ectool --name=cros_fp reboot_ec
ectool --name=cros_fp rollbackinfo
=> Rollback block id:    X+2

Change-Id: I039d26d302d3a12b0d41acca34aa28d4a2dd096d
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1226126
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Reviewed-by: Nicolas Norvez <norvez@chromium.org>
(cherry picked from commit 852a4f2f35602724ac8d784b721df5cdc57ac086)
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1539363
Commit-Queue: Corner Li <cornerli@google.com>
Tested-by: Corner Li <cornerli@google.com>

3 files changed, 56 insertions, 0 deletions

diff --git a/common/rollback.c b/common/rollback.c
index cc5d27cb12..53d840ec46 100644
--- a/common/rollback.c
+++ b/common/rollback.c
@@ -459,3 +459,26 @@ static int command_rollback_info(int argc, char **argv)
 DECLARE_SAFE_CONSOLE_COMMAND(rollbackinfo, command_rollback_info,
 			     NULL,
 			     "Print rollback info");
+
+static int host_command_rollback_info(struct host_cmd_handler_args *args)
+{
+	struct ec_response_rollback_info *r = args->response;
+	int min_region;
+	struct rollback_data data;
+
+	min_region = get_latest_rollback(&data);
+
+	if (min_region < 0)
+		return EC_RES_UNAVAILABLE;
+
+	r->id = data.id;
+	r->rollback_min_version = data.rollback_min_version;
+	r->rw_rollback_version = system_get_rollback_version(SYSTEM_IMAGE_RW);
+
+	args->response_size = sizeof(*r);
+
+	return EC_RES_SUCCESS;
+}
+DECLARE_HOST_COMMAND(EC_CMD_ROLLBACK_INFO,
+		     host_command_rollback_info,
+		     EC_VER_MASK(0));
diff --git a/include/ec_commands.h b/include/ec_commands.h
index 54c7827231..53c84867fb 100644
--- a/include/ec_commands.h
+++ b/include/ec_commands.h
@@ -4886,6 +4886,17 @@ struct __ec_align4 ec_response_adc_read {
 	int32_t adc_value;
 };
 
+/*
+ * Read back rollback info
+ */
+#define EC_CMD_ROLLBACK_INFO		0x0124
+
+struct __ec_align4 ec_response_rollback_info {
+	int32_t id; /* Incrementing number to indicate which region to use. */
+	int32_t rollback_min_version;
+	int32_t rw_rollback_version;
+};
+
 
 /*****************************************************************************/
 /* The command range 0x200-0x2FF is reserved for Rotor. */
diff --git a/util/ectool.c b/util/ectool.c
index 795c5de869..e22e951ac1 100644
--- a/util/ectool.c
+++ b/util/ectool.c
@@ -229,6 +229,8 @@ const char help_str[] =
 	"  reboot_ec <RO|RW|cold|hibernate|hibernate-clear-ap-off|disable-jump>"
 			" [at-shutdown|switch-slot]\n"
 	"      Reboot EC to RO or RW\n"
+	"  rollbackinfo\n"
+	"      Print rollback block information\n"
 	"  rtcget\n"
 	"      Print real-time clock\n"
 	"  rtcgetalarm\n"
@@ -1305,6 +1307,25 @@ int cmd_rwsig_action(int argc, char *argv[])
 	return ec_command(EC_CMD_RWSIG_ACTION, 0, &req, sizeof(req), NULL, 0);
 }
 
+int cmd_rollback_info(int argc, char *argv[])
+{
+	struct ec_response_rollback_info r;
+	int rv;
+
+	rv = ec_command(EC_CMD_ROLLBACK_INFO, 0, NULL, 0, &r, sizeof(r));
+	if (rv < 0) {
+		fprintf(stderr, "ERROR: EC_CMD_ROLLBACK_INFO failed: %d\n", rv);
+		return rv;
+	}
+
+	/* Print versions */
+	printf("Rollback block id:    %d\n", r.id);
+	printf("Rollback min version: %d\n", r.rollback_min_version);
+	printf("RW rollback version:  %d\n", r.rw_rollback_version);
+
+	return rv;
+}
+
 #define FP_FRAME_INDEX_SIMPLE_IMAGE -1
 
 /*
@@ -8364,6 +8385,7 @@ const struct command commands[] = {
 	{"pwmsetduty", cmd_pwm_set_duty},
 	{"readtest", cmd_read_test},
 	{"reboot_ec", cmd_reboot_ec},
+	{"rollbackinfo", cmd_rollback_info},
 	{"rtcget", cmd_rtc_get},
 	{"rtcgetalarm", cmd_rtc_get_alarm},
 	{"rtcset", cmd_rtc_set},