A new SLOF boot menu

The current SLOF boot menu heavily depends on the contents of the
"qemu,boot-list" and "qemu,boot-device"" properties in the device tree,
so that the menu entries either look very strange (when there is no
alias, see https://bugzilla.redhat.com/show_bug.cgi?id=1429832 ) or
are duplicated (https://bugzilla.redhat.com/show_bug.cgi?id=1446018).

A proper boot menu should rather show all available boot devices
instead, so this patch series introduces a new boot menu (written in
C this time) which is independent from the "qemu,boot-list/device"
properties by looking at the available aliases instead. It is now also
possible by selecting the entries with one key stroke only (you don't
have to press RETURN anymore), so this is now hopefully much more user
friendly than the old menu.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>

board-qemu/Makefile

@@ -15,7 +15,7 @@ BOARD_TARGETS = tools_build romfs_build stage1 subdirs
 SUBDIRS = slof
 
 COMMON_LIBS = libc libbootmsg libbases libnvram libelf libhvcall libvirtio \
-              libusb libveth libe1k libnet
+              libusb libveth libe1k libnet libbootmenu
 
 all: $(BOARD_TARGETS)
 	$(MAKE) boot_rom.bin

board-qemu/slof/Makefile

@@ -21,7 +21,8 @@ all: version.o Makefile.dep OF.ffs paflof $(SLOFCMNDIR)/xvect.bin
 CPPFLAGS = -I$(LIBCMNDIR)/libbootmsg -I$(LIBCMNDIR)/libhvcall \
 	   -I$(LIBCMNDIR)/libvirtio -I$(LIBCMNDIR)/libnvram \
 	   -I$(LIBCMNDIR)/libusb -I$(LIBCMNDIR)/libveth \
-	   -I$(LIBCMNDIR)/libe1k -I$(LIBCMNDIR)/libnet
+	   -I$(LIBCMNDIR)/libe1k -I$(LIBCMNDIR)/libnet \
+	   -I$(LIBCMNDIR)/libbootmenu
 SLOF_LIBS = \
 	$(LIBCMNDIR)/libbootmsg.a \
 	$(LIBCMNDIR)/libelf.a \
@@ -31,7 +32,8 @@ SLOF_LIBS = \
 	$(LIBCMNDIR)/libnvram.a \
 	$(LIBCMNDIR)/libveth.a \
 	$(LIBCMNDIR)/libe1k.a \
-	$(LIBCMNDIR)/libnet.a
+	$(LIBCMNDIR)/libnet.a \
+	$(LIBCMNDIR)/libbootmenu.a
 BOARD_SLOF_IN = \
 	$(LIBCMNDIR)/libhvcall/hvcall.in \
 	$(LIBCMNDIR)/libvirtio/virtio.in \
@@ -42,7 +44,8 @@ BOARD_SLOF_IN = \
 	$(LIBCMNDIR)/libbases/libbases.in \
 	$(LIBCMNDIR)/libveth/veth.in \
 	$(LIBCMNDIR)/libe1k/e1k.in \
-	$(LIBCMNDIR)/libnet/libnet.in
+	$(LIBCMNDIR)/libnet/libnet.in \
+	$(LIBCMNDIR)/libbootmenu/bootmenu.in
 BOARD_SLOF_CODE = $(BOARD_SLOF_IN:%.in=%.code)
 
 include $(SLOFCMNDIR)/Makefile.inc

lib/Makefile

@@ -11,7 +11,7 @@
 # ****************************************************************************/
 
 SUBDIRS = libc libipmi libbootmsg libbases libnvram libelf libhvcall libvirtio \
-          libusb libveth libe1k libbcm libnet
+          libusb libveth libe1k libbcm libnet libbootmenu
 
 all:  subdirs
 

lib/libbootmenu/Makefile

@@ -0,0 +1,49 @@
+# *****************************************************************************
+# * Copyright (c) 2004, 2008 IBM Corporation
+# * All rights reserved.
+# * This program and the accompanying materials
+# * are made available under the terms of the BSD License
+# * which accompanies this distribution, and is available at
+# * http://www.opensource.org/licenses/bsd-license.php
+# *
+# * Contributors:
+# *     IBM Corporation - initial implementation
+# ****************************************************************************/
+
+ifndef TOP
+  TOP = $(shell while ! test -e make.rules; do cd ..  ; done; pwd)
+  export TOP
+endif
+include $(TOP)/make.rules
+
+CFLAGS += -I. -I.. -I../libc/include -I$(SLOFCMNDIR) -I$(INCLCMNDIR)
+
+SRCS =	bootmenu.c
+
+OBJS = $(SRCS:%.c=%.o)
+
+TARGET = ../libbootmenu.a
+
+all: $(TARGET)
+
+$(TARGET): $(OBJS)
+	$(AR) -rc $@ $(OBJS)
+	$(RANLIB) $@
+
+clean:
+	$(RM) $(TARGET) $(OBJS)
+
+distclean: clean
+	$(RM) Makefile.dep
+
+
+# Rules for creating the dependency file:
+depend:
+	$(RM) Makefile.dep
+	$(MAKE) Makefile.dep
+
+Makefile.dep: Makefile
+	$(CC) -M $(CPPFLAGS) $(CFLAGS) $(SRCS) > Makefile.dep
+
+# Include dependency file if available:
+-include Makefile.dep

lib/libbootmenu/bootmenu.c

@@ -0,0 +1,187 @@
+/*****************************************************************************
+ * Boot menu: Displays boot devices and waits for user to select one
+ *
+ * Copyright 2017 Red Hat, Inc.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the BSD License
+ * which accompanies this distribution, and is available at
+ * http://www.opensource.org/licenses/bsd-license.php
+ *
+ * Contributors:
+ *     Thomas Huth, Red Hat Inc. - initial implementation
+ *****************************************************************************/
+
+#include <stdbool.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <paflof.h>
+#include <helpers.h>
+#include "bootmenu.h"
+
+#define MAX_DEVS 36        /* Enough for 10 digits + 26 letters */
+#define MAX_ALIAS_LEN 8    /* Maximum length of alias names */
+
+struct bootdev {
+	char alias[MAX_ALIAS_LEN];
+	char *path;
+};
+
+static int nr_devs;
+static struct bootdev bootdevs[MAX_DEVS];
+
+/**
+ * Look up an alias name.
+ * @return The NUL-terminated device tree path (should be released with free()
+ *         when it's not required anymore), or NULL if it can't be found.
+ */
+static char *find_alias(char *alias)
+{
+	char *path;
+	long len;
+
+	forth_push((unsigned long)alias);
+	forth_push(strlen(alias));
+	forth_eval("find-alias");
+
+	len = forth_pop();
+	if (!len)
+		return NULL;
+
+	path = malloc(len + 1);
+	if (!path) {
+		puts("Out of memory in find_alias");
+		return NULL;
+	}
+	memcpy(path, (void *)forth_pop(), len);
+	path[len] = '\0';
+
+	return path;
+}
+
+static void bootmenu_populate_devs_alias(const char *alias)
+{
+	int idx;
+
+	for (idx = 0; idx <= 9 && nr_devs < MAX_DEVS; idx++, nr_devs++) {
+		char *cur_alias = bootdevs[nr_devs].alias;
+		if (idx == 0)
+			strcpy(cur_alias, alias);
+		else
+			sprintf(cur_alias, "%s%i", alias, idx);
+		bootdevs[nr_devs].path = find_alias(cur_alias);
+		if (!bootdevs[nr_devs].path)
+			break;
+	}
+}
+
+static void bootmenu_populate_devs(void)
+{
+	bootmenu_populate_devs_alias("cdrom");
+	bootmenu_populate_devs_alias("disk");
+	bootmenu_populate_devs_alias("net");
+}
+
+static void bootmenu_free_devs(void)
+{
+	while (nr_devs-- > 0) {
+		free(bootdevs[nr_devs].path);
+		bootdevs[nr_devs].path = NULL;
+	}
+}
+
+static void bootmenu_show_devs(void)
+{
+	int i;
+
+	for (i = 0; i < nr_devs; i++) {
+		printf("%c) %6s : %s\n", i < 9 ? '1' + i : 'a' + i - 9,
+		       bootdevs[i].alias, bootdevs[i].path);
+	}
+}
+
+static bool has_key(void)
+{
+	forth_eval("key?");
+	return forth_pop();
+}
+
+static char get_key(void)
+{
+	forth_eval("key");
+	return forth_pop();
+}
+
+/* Flush pending key presses */
+static void flush_keys(void)
+{
+	uint32_t start;
+
+	start = SLOF_GetTimer();
+	while (SLOF_GetTimer() - start < 10) {
+		if (has_key()) {
+			get_key();
+			start = SLOF_GetTimer();
+		}
+	}
+}
+
+static int bootmenu_get_selection(void)
+{
+	char key = 0;
+	int sel;
+
+	do {
+		sel = -1;
+		if (!has_key())
+			continue;
+		key = get_key();
+		switch (key) {
+		case '0':
+			return -1;
+		case '1' ... '9':
+			sel = key - '1';
+			break;
+		case 'a' ... 'z':
+			sel = key - 'a' + 9;
+			break;
+		case 'A' ... 'Z':
+			sel = key - 'A' + 9;
+			break;
+		default:
+			/* Might be another escape code (F12) ... skip it */
+			flush_keys();
+			break;
+		}
+	} while (sel < 0 || sel >= nr_devs);
+
+	return sel;
+}
+
+void bootmenu(void)
+{
+	int sel;
+
+	bootmenu_populate_devs();
+	if (!nr_devs) {
+		puts("No available boot devices!");
+		return;
+	}
+
+	puts("\nSelect boot device (or press '0' to abort):");
+	bootmenu_show_devs();
+
+	if (has_key())		/* In case the user hammered on F12 */
+		flush_keys();
+
+	sel = bootmenu_get_selection();
+	if (sel < 0) {
+		forth_push(0);
+	} else {
+		forth_push((unsigned long)bootdevs[sel].alias);
+		forth_push(strlen(bootdevs[sel].alias));
+	}
+
+	bootmenu_free_devs();
+}

lib/libbootmenu/bootmenu.code

@@ -0,0 +1,20 @@
+/*****************************************************************************
+ * Boot menu: Glue code to Forth
+ *
+ * Copyright 2017 Red Hat, Inc.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the BSD License
+ * which accompanies this distribution, and is available at
+ * http://www.opensource.org/licenses/bsd-license.php
+ *
+ * Contributors:
+ *     Thomas Huth, Red Hat Inc. - initial implementation
+ *****************************************************************************/
+
+#include "bootmenu.h"
+
+// ( -- [str] len|0 )
+PRIM(boot_X2d_menu)
+	bootmenu();
+MIRP

lib/libbootmenu/bootmenu.h

@@ -0,0 +1,15 @@
+/*****************************************************************************
+ * Boot menu definitions
+ *
+ * Copyright 2017 Red Hat, Inc.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the BSD License
+ * which accompanies this distribution, and is available at
+ * http://www.opensource.org/licenses/bsd-license.php
+ *
+ * Contributors:
+ *     Thomas Huth, Red Hat Inc. - initial implementation
+ *****************************************************************************/
+
+extern void bootmenu(void);

lib/libbootmenu/bootmenu.in

@@ -0,0 +1,15 @@
+/*****************************************************************************
+ * Boot menu: Definitions for Forth
+ *
+ * Copyright 2017 Red Hat, Inc.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the BSD License
+ * which accompanies this distribution, and is available at
+ * http://www.opensource.org/licenses/bsd-license.php
+ *
+ * Contributors:
+ *     Thomas Huth, Red Hat Inc. - initial implementation
+ *****************************************************************************/
+
+cod(boot-menu)

slof/fs/start-up.fs

@@ -65,70 +65,17 @@
 \ Watchdog will be rearmed during load if use-load-watchdog variable is TRUE
 TRUE VALUE use-load-watchdog?
 
-1 value my-boot-dev
-1 value digit-val
-0 value boot-dev-no
-
-: boot-selected
-   1 to my-boot-dev
-   BEGIN parse-word dup WHILE
-      boot-dev-no my-boot-dev = IF
-         s" boot " 2swap $cat
-         ['] evaluate catch ?dup IF     \ and execute it
-            ." boot attempt returned: "
-            abort"-str @ count type cr
-            throw
-         THEN
-         0 0 load-list 2!
-         UNLOOP EXIT
-      ELSE
-         2drop
-      THEN
-      my-boot-dev 1 + to my-boot-dev
-   REPEAT 2drop 0 0 load-list 2!
-
-   (boot)
-;
-
-: boot-start
-   decimal
-   BEGIN parse-word dup WHILE
-      my-boot-dev (u.) s" . " $cat type 2dup type ." : " de-alias type cr
-      my-boot-dev 1 + to my-boot-dev
-   REPEAT 2drop 0 0 load-list 2!
-
-   \ Clear pending keys (to remove multiple F12 key presses for example)
-   BEGIN key? WHILE
-      key drop
-   REPEAT
-
-   cr
-   BEGIN
-      KEY
-      dup 1b = IF         \ ESC sequence ... could be yet another F12 key press
-         BEGIN key? WHILE
-            key drop
-         REPEAT
-      ELSE
-         dup emit
-      THEN
-      dup isdigit IF
-         dup 30 - to digit-val
-         boot-dev-no a * digit-val + to boot-dev-no
-      THEN
-   d = UNTIL
-
-   boot-dev-no my-boot-dev < IF
-      s" boot-selected " s" $bootdev" evaluate $cat strdup evaluate
-   ELSE
-      ." Invalid choice!" cr
-   THEN
-   hex
-;
 
 : boot-menu-start
-   ." Select boot device:" cr cr
-   s" boot-start " s" $bootdev" evaluate $cat strdup evaluate
+    boot-menu ?dup IF
+       s" boot " 2swap $cat
+       ['] evaluate catch ?dup IF
+           ." boot attempt returned: "
+           abort"-str @ count type cr
+           throw
+       THEN
+       0 0 load-list 2!
+    THEN
 ;
 
 : boot-menu-enabled? ( -- true|false )