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, 42 insertions, 2 deletions

diff --git a/cmd/bootflow.c b/cmd/bootflow.c
index 313103d277..2b6ed26fdc 100644
--- a/cmd/bootflow.c
+++ b/cmd/bootflow.c
@@ -337,6 +337,13 @@ static int do_bootflow_info(struct cmd_tbl *cmdtp, int flag, int argc,
 	printf("Filename:  %s\n", bflow->fname);
 	printf("Buffer:    %lx\n", (ulong)map_to_sysmem(bflow->buf));
 	printf("Size:      %x (%d bytes)\n", bflow->size, bflow->size);
+	printf("OS:        %s\n", bflow->os_name ? bflow->os_name : "(none)");
+	printf("Logo:      %s\n", bflow->logo ?
+	       simple_xtoa((ulong)map_to_sysmem(bflow->logo)) : "(none)");
+	if (bflow->logo) {
+		printf("Logo size: %x (%d bytes)\n", bflow->logo_size,
+		       bflow->logo_size);
+	}
 	printf("Error:     %d\n", bflow->err);
 	if (dump && bflow->buf) {
 		/* Set some sort of maximum on the size */
@@ -382,6 +389,37 @@ static int do_bootflow_boot(struct cmd_tbl *cmdtp, int flag, int argc,
 
 	return 0;
 }
+
+static int do_bootflow_menu(struct cmd_tbl *cmdtp, int flag, int argc,
+			    char *const argv[])
+{
+	struct bootstd_priv *std;
+	struct bootflow *bflow;
+	bool text_mode = false;
+	int ret;
+
+	if (argc > 1 && *argv[1] == '-')
+		text_mode = strchr(argv[1], 't');
+
+	ret = bootstd_get_priv(&std);
+	if (ret)
+		return CMD_RET_FAILURE;
+
+	ret = bootflow_menu_run(std, text_mode, &bflow);
+	if (ret) {
+		if (ret == -EAGAIN)
+			printf("Nothing chosen\n");
+		else
+			printf("Menu failed (err=%d)\n", ret);
+
+		return CMD_RET_FAILURE;
+	}
+
+	printf("Selected: %s\n", bflow->os_name ? bflow->os_name : bflow->name);
+	std->cur_bootflow = bflow;
+
+	return 0;
+}
 #endif /* CONFIG_CMD_BOOTFLOW_FULL */
 
 #ifdef CONFIG_SYS_LONGHELP
@@ -391,7 +429,8 @@ static char bootflow_help_text[] =
 	"bootflow list [-e]             - list scanned bootflows (-e errors)\n"
 	"bootflow select [<num>|<name>] - select a bootflow\n"
 	"bootflow info [-d]             - show info on current bootflow (-d dump bootflow)\n"
-	"bootflow boot                  - boot current bootflow (or first available if none selected)";
+	"bootflow boot                  - boot current bootflow (or first available if none selected)\n"
+	"bootflow menu [-t]             - show a menu of available bootflows";
 #else
 	"scan - boot first available bootflow\n";
 #endif
@@ -403,6 +442,7 @@ U_BOOT_CMD_WITH_SUBCMDS(bootflow, "Boot flows", bootflow_help_text,
 	U_BOOT_SUBCMD_MKENT(list, 2, 1, do_bootflow_list),
 	U_BOOT_SUBCMD_MKENT(select, 2, 1, do_bootflow_select),
 	U_BOOT_SUBCMD_MKENT(info, 2, 1, do_bootflow_info),
-	U_BOOT_SUBCMD_MKENT(boot, 1, 1, do_bootflow_boot)
+	U_BOOT_SUBCMD_MKENT(boot, 1, 1, do_bootflow_boot),
+	U_BOOT_SUBCMD_MKENT(menu, 2, 1, do_bootflow_menu),
 #endif
 );