Merge branch '2022-01-16-bootstd-updates'

To quote the author:
So far standard boot lacks a boot menu, although it is possible to create
a rudimentary one using the existing 'bootmenu' command.

Even then, this text-based menu offer only basic functionality and does
not take full advantage of the displays which are common on many devices.

This series provides a 'bootflow menu' command which allows the user to
select from the available bootflows. An attempt is made to show the name
of the available operating systems, by reading more information into the
bootflow. A logo can be read also, where supported, so that this can be
presented to the user when an option is highlighted.

Full use is made of TrueType fonts, if enabled. For cases where only a
serial console is available, it falls back to a simple text-based menu.

All of this is implementing using a new 'expo' construct, a collection of
scenes (like menu screens) which can be navigated by the user to view
information and select options. This is fairly general and should be able
to cope with a wider array of use cases, with less hacking of the menu
code, such as is currently needed for CMD_BOOTEFI_BOOTMGR.

Of course it would be possible to enhance the existing menu rather than
creating a new setup. Instead it seems better to make the existing menu
use expo, if code space permits. It avoids the event-loop problem and
should be more extensible, given its loosely coupled components and use of
IDs instead of pointers. Further motivation is provided in the
documentation.

For now the CLI keypress-decoding code is split out to be used by the new
menu. The key codes defined by menu.h are reused also.

This is of course just a starting point. Some ideas for future work are
included in the documentation.

1 files changed, 284 insertions, 0 deletions

diff --git a/boot/bootflow_menu.c b/boot/bootflow_menu.c
new file mode 100644
index 0000000000..7f06dac0af
--- /dev/null
+++ b/boot/bootflow_menu.c
@@ -0,0 +1,284 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Provide a menu of available bootflows and related options
+ *
+ * Copyright 2022 Google LLC
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#define LOG_CATEGORY UCLASS_BOOTSTD
+
+#include <common.h>
+#include <bootflow.h>
+#include <bootstd.h>
+#include <cli.h>
+#include <dm.h>
+#include <expo.h>
+#include <malloc.h>
+#include <menu.h>
+#include <video_console.h>
+#include <watchdog.h>
+#include <linux/delay.h>
+#include "bootflow_internal.h"
+
+/**
+ * struct menu_priv - information about the menu
+ *
+ * @num_bootflows: Number of bootflows in the menu
+ */
+struct menu_priv {
+	int num_bootflows;
+};
+
+int bootflow_menu_new(struct expo **expp)
+{
+	struct udevice *last_bootdev;
+	struct scene_obj_menu *menu;
+	struct menu_priv *priv;
+	struct bootflow *bflow;
+	struct scene *scn;
+	struct expo *exp;
+	void *logo;
+	int ret, i;
+
+	priv = calloc(1, sizeof(*priv));
+	if (!priv)
+		return log_msg_ret("prv", -ENOMEM);
+
+	ret = expo_new("bootflows", priv, &exp);
+	if (ret)
+		return log_msg_ret("exp", ret);
+
+	ret = scene_new(exp, "main", MAIN, &scn);
+	if (ret < 0)
+		return log_msg_ret("scn", ret);
+
+	ret |= scene_txt_str(scn, "prompt", OBJ_PROMPT, STR_PROMPT,
+			     "UP and DOWN to choose, ENTER to select", NULL);
+
+	ret = scene_menu(scn, "main", OBJ_MENU, &menu);
+	ret |= scene_obj_set_pos(scn, OBJ_MENU, MARGIN_LEFT, 100);
+	ret |= scene_txt_str(scn, "title", OBJ_MENU_TITLE, STR_MENU_TITLE,
+			     "U-Boot - Boot Menu", NULL);
+	ret |= scene_menu_set_title(scn, OBJ_MENU, OBJ_PROMPT);
+
+	logo = video_get_u_boot_logo();
+	if (logo) {
+		ret |= scene_img(scn, "ulogo", OBJ_U_BOOT_LOGO, logo, NULL);
+		ret |= scene_obj_set_pos(scn, OBJ_U_BOOT_LOGO, -4, 4);
+	}
+
+	ret |= scene_txt_str(scn, "cur_item", OBJ_POINTER, STR_POINTER, ">",
+			     NULL);
+	ret |= scene_menu_set_pointer(scn, OBJ_MENU, OBJ_POINTER);
+	if (ret < 0)
+		return log_msg_ret("new", -EINVAL);
+
+	last_bootdev = NULL;
+	for (ret = bootflow_first_glob(&bflow), i = 0; !ret && i < 36;
+	     ret = bootflow_next_glob(&bflow), i++) {
+		char str[2], *label, *key;
+		uint preview_id;
+		bool add_gap;
+
+		if (bflow->state != BOOTFLOWST_READY)
+			continue;
+
+		*str = i < 10 ? '0' + i : 'A' + i - 10;
+		str[1] = '\0';
+		key = strdup(str);
+		if (!key)
+			return log_msg_ret("key", -ENOMEM);
+		label = strdup(dev_get_parent(bflow->dev)->name);
+		if (!label) {
+			free(key);
+			return log_msg_ret("nam", -ENOMEM);
+		}
+
+		add_gap = last_bootdev != bflow->dev;
+		last_bootdev = bflow->dev;
+
+		ret = expo_str(exp, "prompt", STR_POINTER, ">");
+		ret |= scene_txt_str(scn, "label", ITEM_LABEL + i,
+				      STR_LABEL + i, label, NULL);
+		ret |= scene_txt_str(scn, "desc", ITEM_DESC + i, STR_DESC + i,
+				    bflow->os_name ? bflow->os_name :
+				    bflow->name, NULL);
+		ret |= scene_txt_str(scn, "key", ITEM_KEY + i, STR_KEY + i, key,
+				      NULL);
+		preview_id = 0;
+		if (bflow->logo) {
+			preview_id = ITEM_PREVIEW + i;
+			ret |= scene_img(scn, "preview", preview_id,
+					     bflow->logo, NULL);
+		}
+		ret |= scene_menuitem(scn, OBJ_MENU, "item", ITEM + i,
+					  ITEM_KEY + i, ITEM_LABEL + i,
+					  ITEM_DESC + i, preview_id,
+					  add_gap ? SCENEMIF_GAP_BEFORE : 0,
+					  NULL);
+
+		if (ret < 0)
+			return log_msg_ret("itm", -EINVAL);
+		ret = 0;
+		priv->num_bootflows++;
+	}
+
+	*expp = exp;
+
+	return 0;
+}
+
+int bootflow_menu_apply_theme(struct expo *exp, ofnode node)
+{
+	struct menu_priv *priv = exp->priv;
+	struct scene *scn;
+	u32 font_size;
+	int ret;
+
+	log_debug("Applying theme %s\n", ofnode_get_name(node));
+	scn = expo_lookup_scene_id(exp, MAIN);
+	if (!scn)
+		return log_msg_ret("scn", -ENOENT);
+
+	/* Avoid error-checking optional items */
+	if (!ofnode_read_u32(node, "font-size", &font_size)) {
+		int i;
+
+		log_debug("font size %d\n", font_size);
+		scene_txt_set_font(scn, OBJ_PROMPT, NULL, font_size);
+		scene_txt_set_font(scn, OBJ_POINTER, NULL, font_size);
+		for (i = 0; i < priv->num_bootflows; i++) {
+			ret = scene_txt_set_font(scn, ITEM_DESC + i, NULL,
+						 font_size);
+			if (ret)
+				return log_msg_ret("des", ret);
+			scene_txt_set_font(scn, ITEM_KEY + i, NULL, font_size);
+			scene_txt_set_font(scn, ITEM_LABEL + i, NULL,
+					   font_size);
+		}
+	}
+
+	ret = scene_arrange(scn);
+	if (ret)
+		return log_msg_ret("arr", ret);
+
+	return 0;
+}
+
+int bootflow_menu_run(struct bootstd_priv *std, bool text_mode,
+		      struct bootflow **bflowp)
+{
+	struct cli_ch_state s_cch, *cch = &s_cch;
+	struct bootflow *sel_bflow;
+	struct udevice *dev;
+	struct expo *exp;
+	uint sel_id;
+	bool done;
+	int ret;
+
+	cli_ch_init(cch);
+
+	sel_bflow = NULL;
+	*bflowp = NULL;
+
+	ret = bootflow_menu_new(&exp);
+	if (ret)
+		return log_msg_ret("exp", ret);
+
+	if (ofnode_valid(std->theme)) {
+		ret = bootflow_menu_apply_theme(exp, std->theme);
+		if (ret)
+			return log_msg_ret("thm", ret);
+	}
+
+	/* For now we only support a video console */
+	ret = uclass_first_device_err(UCLASS_VIDEO, &dev);
+	if (ret)
+		return log_msg_ret("vid", ret);
+	ret = expo_set_display(exp, dev);
+	if (ret)
+		return log_msg_ret("dis", ret);
+
+	ret = expo_set_scene_id(exp, MAIN);
+	if (ret)
+		return log_msg_ret("scn", ret);
+
+	if (text_mode)
+		exp_set_text_mode(exp, text_mode);
+
+	done = false;
+	do {
+		struct expo_action act;
+		int ichar, key;
+
+		ret = expo_render(exp);
+		if (ret)
+			break;
+
+		ichar = cli_ch_process(cch, 0);
+		if (!ichar) {
+			while (!ichar && !tstc()) {
+				schedule();
+				mdelay(2);
+				ichar = cli_ch_process(cch, -ETIMEDOUT);
+			}
+			if (!ichar) {
+				ichar = getchar();
+				ichar = cli_ch_process(cch, ichar);
+			}
+		}
+
+		key = 0;
+		if (ichar) {
+			key = bootmenu_conv_key(ichar);
+			if (key == BKEY_NONE)
+				key = ichar;
+		}
+		if (!key)
+			continue;
+
+		ret = expo_send_key(exp, key);
+		if (ret)
+			break;
+
+		ret = expo_action_get(exp, &act);
+		if (!ret) {
+			switch (act.type) {
+			case EXPOACT_SELECT:
+				sel_id = act.select.id;
+				done = true;
+				break;
+			case EXPOACT_QUIT:
+				done = true;
+				break;
+			default:
+				break;
+			}
+		}
+	} while (!done);
+
+	if (ret)
+		return log_msg_ret("end", ret);
+
+	if (sel_id) {
+		struct bootflow *bflow;
+		int i;
+
+		for (ret = bootflow_first_glob(&bflow), i = 0; !ret && i < 36;
+		     ret = bootflow_next_glob(&bflow), i++) {
+			if (i == sel_id - ITEM) {
+				sel_bflow = bflow;
+				break;
+			}
+		}
+	}
+
+	expo_destroy(exp);
+
+	if (!sel_bflow)
+		return -EAGAIN;
+	*bflowp = sel_bflow;
+
+	return 0;
+}