firmware/2lib: Add visual/audio error handling

Adding an enum parameter to vb2ex_display_ui to facilitate printing
errors to the screen.  Currently, errors are only printed to the
serial console. Also adding in beep if an error is displayed.

BUG=b:144969091,b:158635317,b:158639298,b:146399181
BRANCH=None
TEST=Boot into dev warning screen and try to hit ctrl-u when no USB is
     plugged in.  Ensure error beep occurs.
     Ensure in dev mode.  Boot into recovery and press ctrl-d.
     Ensure that error message is printed to the screen and beep occurs.
     make runtests

Cq-Depend: chromium:2243513
Change-Id: I548d624532ad8816497c37a726275b33171e28dc
Signed-off-by: Shelley Chen <shchen@google.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/2243196
Tested-by: Shelley Chen <shchen@chromium.org>
Reviewed-by: Yu-Ping Wu <yupingso@chromium.org>
Commit-Queue: Shelley Chen <shchen@chromium.org>

7 files changed, 71 insertions, 11 deletions

diff --git a/firmware/2lib/2ui.c b/firmware/2lib/2ui.c
index 96a7b939..4d363f68 100644
--- a/firmware/2lib/2ui.c
+++ b/firmware/2lib/2ui.c
@@ -72,6 +72,20 @@ vb2_error_t check_shutdown_request(struct vb2_ui_context *ui)
 }
 
 /*****************************************************************************/
+/* Error action functions */
+
+vb2_error_t error_exit_action(struct vb2_ui_context *ui)
+{
+	/*
+	 * If the only difference is the error message, then just
+	 * redraw the screen without the error string.
+	 */
+	if (ui->key && ui->error_code != VB2_UI_ERROR_NONE)
+		ui->error_code = VB2_UI_ERROR_NONE;
+	return VB2_REQUEST_UI_CONTINUE;
+}
+
+/*****************************************************************************/
 /* Menu navigation functions */
 
 const struct vb2_menu *get_menu(struct vb2_ui_context *ui)
@@ -236,6 +250,7 @@ vb2_error_t ui_loop(struct vb2_context *ctx, enum vb2_screen root_screen_id,
 {
 	struct vb2_ui_context ui;
 	struct vb2_screen_state prev_state;
+	enum vb2_ui_error prev_error_code;
 	const struct vb2_menu *menu;
 	uint32_t key_flags;
 	vb2_error_t rv;
@@ -250,11 +265,13 @@ vb2_error_t ui_loop(struct vb2_context *ctx, enum vb2_screen root_screen_id,
 	if (rv != VB2_REQUEST_UI_CONTINUE)
 		return rv;
 	memset(&prev_state, 0, sizeof(prev_state));
+	prev_error_code = VB2_UI_ERROR_NONE;
 
 	while (1) {
 		/* Draw if there are state changes. */
-		if (memcmp(&prev_state, &ui.state, sizeof(ui.state))) {
-			memcpy(&prev_state, &ui.state, sizeof(ui.state));
+		if (memcmp(&prev_state, &ui.state, sizeof(ui.state)) ||
+		    /* we want to redraw/beep on a transition */
+		    prev_error_code != ui.error_code) {
 
 			menu = get_menu(&ui);
 			VB2_DEBUG("<%s> menu item <%s>\n",
@@ -262,10 +279,21 @@ vb2_error_t ui_loop(struct vb2_context *ctx, enum vb2_screen root_screen_id,
 				  menu->num_items ?
 				  menu->items[ui.state.selected_item].text :
 				  "null");
-
 			vb2ex_display_ui(ui.state.screen->id, ui.locale_id,
 					 ui.state.selected_item,
-					 ui.state.disabled_item_mask);
+					 ui.state.disabled_item_mask,
+					 ui.error_code);
+			/*
+			 * Only beep if we're transitioning from no
+			 * error to an error.
+			 */
+			if (prev_error_code == VB2_UI_ERROR_NONE &&
+			    ui.error_code != VB2_UI_ERROR_NONE)
+				vb2ex_beep(250, 400);
+
+			/* Update prev variables. */
+			memcpy(&prev_state, &ui.state, sizeof(ui.state));
+			prev_error_code = ui.error_code;
 		}
 
 		/* Grab new keyboard input. */
@@ -279,6 +307,11 @@ vb2_error_t ui_loop(struct vb2_context *ctx, enum vb2_screen root_screen_id,
 			return rv;
 		}
 
+		/* Check if we need to exit an error box. */
+		rv = error_exit_action(&ui);
+		if (rv != VB2_REQUEST_UI_CONTINUE)
+			return rv;
+
 		/* Run screen action. */
 		if (ui.state.screen->action) {
 			rv = ui.state.screen->action(&ui);
diff --git a/firmware/2lib/2ui_screens.c b/firmware/2lib/2ui_screens.c
index 042d6d4c..c43abb8f 100644
--- a/firmware/2lib/2ui_screens.c
+++ b/firmware/2lib/2ui_screens.c
@@ -249,7 +249,8 @@ static const struct vb2_screen_info recovery_invalid_screen = {
 vb2_error_t recovery_to_dev_init(struct vb2_ui_context *ui)
 {
 	if (vb2_get_sd(ui->ctx)->flags & VB2_SD_FLAG_DEV_MODE_ENABLED) {
-		VB2_DEBUG("Dev mode already enabled?\n");
+		/* We're in dev mode, so let user know they can't transition */
+		ui->error_code = VB2_UI_ERROR_DEV_MODE_ALREADY_ENABLED;
 		return vb2_ui_change_root(ui);
 	}
 
@@ -489,6 +490,7 @@ vb2_error_t vb2_ui_developer_mode_boot_external_action(
 	    !vb2_dev_boot_allowed(ui->ctx) ||
 	    !vb2_dev_boot_external_allowed(ui->ctx)) {
 		VB2_DEBUG("ERROR: Dev mode external boot not allowed\n");
+		ui->error_code = VB2_UI_ERROR_DEV_EXTERNAL_NOT_ALLOWED;
 		return VB2_REQUEST_UI_CONTINUE;
 	}
 
@@ -496,13 +498,17 @@ vb2_error_t vb2_ui_developer_mode_boot_external_action(
 	if (rv == VB2_SUCCESS) {
 		return VB2_SUCCESS;
 	} else if (rv == VB2_ERROR_LK_NO_DISK_FOUND) {
-		if (ui->state.screen->id != VB2_SCREEN_DEVELOPER_BOOT_EXTERNAL)
+		if (ui->state.screen->id != VB2_SCREEN_DEVELOPER_BOOT_EXTERNAL) {
 			VB2_DEBUG("No external disk found\n");
+			ui->error_code = VB2_UI_ERROR_DEV_EXTERNAL_BOOT_FAILED;
+		}
 		return vb2_ui_change_screen(
 			ui, VB2_SCREEN_DEVELOPER_BOOT_EXTERNAL);
 	} else {
-		if (ui->state.screen->id != VB2_SCREEN_DEVELOPER_INVALID_DISK)
+		if (ui->state.screen->id != VB2_SCREEN_DEVELOPER_INVALID_DISK) {
 			VB2_DEBUG("Invalid external disk: %#x\n", rv);
+			ui->error_code = VB2_UI_ERROR_DEV_EXTERNAL_BOOT_FAILED;
+		}
 		return vb2_ui_change_screen(
 			ui, VB2_SCREEN_DEVELOPER_INVALID_DISK);
 	}
diff --git a/firmware/2lib/include/2api.h b/firmware/2lib/include/2api.h
index 9131dea0..69fd1458 100644
--- a/firmware/2lib/include/2api.h
+++ b/firmware/2lib/include/2api.h
@@ -1234,21 +1234,36 @@ enum vb2_screen {
 	VB2_SCREEN_DEVELOPER_INVALID_DISK	= 0x330,
 };
 
+enum vb2_ui_error {
+	/* No error */
+	VB2_UI_ERROR_NONE = 0,
+	/* Dev mode already enabled */
+	VB2_UI_ERROR_DEV_MODE_ALREADY_ENABLED,
+	/* Dev mode internal boot not allowed */
+	VB2_UI_ERROR_DEV_INTERNAL_NOT_ALLOWED,
+	/* Dev mode external boot not allowed */
+	VB2_UI_ERROR_DEV_EXTERNAL_NOT_ALLOWED,
+	/* Dev mode external boot failed */
+	VB2_UI_ERROR_DEV_EXTERNAL_BOOT_FAILED,
+};
+
 /**
  * Display UI screen.
  *
  * @param screen		Screen to display.
+ * @param locale_id		Id of current locale.
  * @param selected_item		Index of the selected menu item. If the screen
  *				doesn't have a menu, this value will be ignored.
  * @param disabled_item_mask	Mask for disabled menu items. Bit (1 << idx)
  *				indicates whether item 'idx' is disabled.
- * @param locale_id		Id of current locale.
+ * @param error_code		Error code if an error occurred.
  * @return VB2_SUCCESS, or error code on error.
  */
 vb2_error_t vb2ex_display_ui(enum vb2_screen screen,
 			     uint32_t locale_id,
 			     uint32_t selected_item,
-			     uint32_t disabled_item_mask);
+			     uint32_t disabled_item_mask,
+			     enum vb2_ui_error error_code);
 
 /**
  * Check that physical presence button is currently pressed by the user.
diff --git a/firmware/2lib/include/2ui.h b/firmware/2lib/include/2ui.h
index 49f51b32..652362dc 100644
--- a/firmware/2lib/include/2ui.h
+++ b/firmware/2lib/include/2ui.h
@@ -88,6 +88,9 @@ struct vb2_ui_context {
 
 	/* For language selection screen. */
 	struct vb2_menu language_menu;
+
+	/* For displaying error messages. */
+  	enum vb2_ui_error error_code;
 };
 
 vb2_error_t vb2_ui_developer_mode_boot_internal_action(
diff --git a/firmware/2lib/include/2ui_private.h b/firmware/2lib/include/2ui_private.h
index effa280d..ab353955 100644
--- a/firmware/2lib/include/2ui_private.h
+++ b/firmware/2lib/include/2ui_private.h
@@ -13,6 +13,7 @@
 /* From 2ui.c */
 vb2_error_t check_shutdown_request(struct vb2_ui_context *ui);
 const struct vb2_menu *get_menu(struct vb2_ui_context *ui);
+vb2_error_t error_exit_action(struct vb2_ui_context *ui);
 vb2_error_t menu_navigation_action(struct vb2_ui_context *ui);
 vb2_error_t ui_loop(struct vb2_context *ctx, enum vb2_screen root_screen_id,
 		    vb2_error_t (*global_action)(struct vb2_ui_context *ui));
diff --git a/tests/vb2_ui_action_tests.c b/tests/vb2_ui_action_tests.c
index 13c283a8..a664c191 100644
--- a/tests/vb2_ui_action_tests.c
+++ b/tests/vb2_ui_action_tests.c
@@ -383,7 +383,8 @@ const struct vb2_screen_info *vb2_get_screen_info(enum vb2_screen screen)
 vb2_error_t vb2ex_display_ui(enum vb2_screen screen,
 			     uint32_t locale_id,
 			     uint32_t selected_item,
-			     uint32_t disabled_item_mask)
+			     uint32_t disabled_item_mask,
+			     enum vb2_ui_error error_code)
 {
 	struct display_call displayed = (struct display_call){
 		.screen = vb2_get_screen_info(screen),
diff --git a/tests/vb2_ui_tests.c b/tests/vb2_ui_tests.c
index 407a081f..a56e0a4a 100644
--- a/tests/vb2_ui_tests.c
+++ b/tests/vb2_ui_tests.c
@@ -325,7 +325,8 @@ struct vb2_gbb_header *vb2_get_gbb(struct vb2_context *c)
 vb2_error_t vb2ex_display_ui(enum vb2_screen screen,
 			     uint32_t locale_id,
 			     uint32_t selected_item,
-			     uint32_t disabled_item_mask)
+			     uint32_t disabled_item_mask,
+			     enum vb2_ui_error error_code)
 {
 	struct display_call displayed = (struct display_call){
 		.screen = vb2_get_screen_info(screen),