version: Make ver_get_num_commits work for on-flash images

EFS needs to check whether a RW version on flash is equal to or newer
for rollback protection before jumping to a RW copy.

Currently, ver_get_numcommits works only for the running image. This
makes it work for images on flash as well.

Signed-off-by: Daisuke Nojiri <dnojiri@chromium.org>

BUG=chromium:998135
BRANCH=none
TEST=Boot Nami. Verify version numbers are read from RAM and flash.

Change-Id: I94475e40f89dc4c3173d83cb1d9d4ad38d6fab79
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1450816
Reviewed-by: Jett Rink <jettrink@chromium.org>
Reviewed-by: Daisuke Nojiri <dnojiri@chromium.org>
Reviewed-by: Aseda Aboagye <aaboagye@chromium.org>
Commit-Queue: Daisuke Nojiri <dnojiri@chromium.org>
Tested-by: Daisuke Nojiri <dnojiri@chromium.org>

5 files changed, 43 insertions, 20 deletions

diff --git a/common/system.c b/common/system.c
index c7918b96f6..9efb931baa 100644
--- a/common/system.c
+++ b/common/system.c
@@ -668,8 +668,7 @@ uint32_t flash_get_rw_offset(enum system_image_copy_t copy)
 	return CONFIG_EC_PROTECTED_STORAGE_OFF + CONFIG_RO_STORAGE_OFF;
 }
 
-static const struct image_data *system_get_image_data(
-					enum system_image_copy_t copy)
+const struct image_data *system_get_image_data(enum system_image_copy_t copy)
 {
 	static struct image_data data;
 
diff --git a/common/usb_pd_policy.c b/common/usb_pd_policy.c
index b36e29dbcf..74291e1e23 100644
--- a/common/usb_pd_policy.c
+++ b/common/usb_pd_policy.c
@@ -1053,7 +1053,7 @@ void pd_get_info(uint32_t *info_data)
 	defined(CONFIG_USB_PD_HW_DEV_ID_BOARD_MINOR)
 	info_data[5] = VDO_INFO(CONFIG_USB_PD_HW_DEV_ID_BOARD_MAJOR,
 				CONFIG_USB_PD_HW_DEV_ID_BOARD_MINOR,
-				ver_get_numcommits(),
+				ver_get_num_commits(system_get_image_copy()),
 				(system_get_image_copy() != SYSTEM_IMAGE_RO));
 #else
 	info_data[5] = 0;
diff --git a/common/version.c b/common/version.c
index 962f4621e8..13a200b1b5 100644
--- a/common/version.c
+++ b/common/version.c
@@ -9,6 +9,8 @@
 #include "common.h"
 #include "compile_time_macros.h"
 #include "ec_version.h"
+#include "stddef.h"
+#include "system.h"
 #include "version.h"
 
 BUILD_ASSERT(CONFIG_ROLLBACK_VERSION >= 0);
@@ -28,19 +30,15 @@ const struct image_data __keep current_image_data
 const char build_info[] __keep __attribute__((section(".rodata.buildinfo"))) =
 	VERSION " " DATE " " BUILDER;
 
-uint32_t ver_get_numcommits(void)
+static int get_num_commits(const struct image_data *data)
 {
-	int i;
 	int numperiods = 0;
-	uint32_t ret = 0;
-
-	/*
-	 * Version string is formatted like:
-	 * name_major.branch.numcommits-hash[dirty]
-	 * we want to return the numcommits as an int.
-	 */
-	for (i = 0; i < 32; i++) {
-		if (current_image_data.version[i] == '.') {
+	int ret = 0;
+	size_t i;
+
+	/* Version string format is name_major.branch.commits-hash[dirty] */
+	for (i = 0; i < sizeof(data->version); i++) {
+		if (data->version[i] == '.') {
 			numperiods++;
 			if (numperiods == 2)
 				break;
@@ -48,12 +46,27 @@ uint32_t ver_get_numcommits(void)
 	}
 
 	i++;
-	for (; i < 32; i++) {
-		if (current_image_data.version[i] == '-')
+	for (; i < sizeof(data->version); i++) {
+		int d;
+		if (data->version[i] == '-')
 			break;
 		ret *= 10;
-		ret += current_image_data.version[i] - '0';
+		d = data->version[i] - '0';
+		if (d < 0 || d > 9)
+			return 0;
+		ret += d;
 	}
 
-	return (i == 32 ? 0 : ret);
+	return (i == sizeof(data->version) ? 0 : ret);
+
+}
+
+int ver_get_num_commits(enum system_image_copy_t copy)
+{
+	const struct image_data *data;
+	if (IS_ENABLED(CONFIG_COMMON_RUNTIME))
+		data = system_get_image_data(copy);
+	else
+		data = &current_image_data;
+	return data ? get_num_commits(data) : 0;
 }
diff --git a/include/system.h b/include/system.h
index b215dadbf4..a5579e5cfe 100644
--- a/include/system.h
+++ b/include/system.h
@@ -200,6 +200,14 @@ int system_run_image_copy(enum system_image_copy_t copy);
 int32_t system_get_rollback_version(enum system_image_copy_t copy);
 
 /**
+ * Get the image data of an image
+ *
+ * @param copy	Image copy to get the version of.
+ * @return	Image data
+ */
+const struct image_data *system_get_image_data(enum system_image_copy_t copy);
+
+/**
  * Get the version string for an image
  *
  * @param copy		Image copy to get version from, or SYSTEM_IMAGE_UNKNOWN
diff --git a/include/version.h b/include/version.h
index d11ac7d9d9..71e215c8e2 100644
--- a/include/version.h
+++ b/include/version.h
@@ -9,6 +9,7 @@
 #define __CROS_EC_VERSION_H
 
 #include "common.h"
+#include "system.h"
 
 #define CROS_EC_IMAGE_DATA_COOKIE1 0xce778899
 #define CROS_EC_IMAGE_DATA_COOKIE2 0xceaabbdd
@@ -27,7 +28,9 @@ extern const char __image_data_offset[];
 extern const void *__image_size;
 
 /**
- * Get the number of commits field from version string.
+ * Get the number of commits of an image
+ *
+ * @return Number of commits in integer or 0 on error
  */
-uint32_t ver_get_numcommits(void);
+int ver_get_num_commits(enum system_image_copy_t copy);
 #endif  /* __CROS_EC_VERSION_H */