1 files changed, 127 insertions, 0 deletions
diff --git a/firmware.c b/firmware.c
new file mode 100644
index 0000000..34b2918
--- /dev/null
+++ b/firmware.c
@@ -0,0 +1,127 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "bootloader.h"
+#include "common.h"
+#include "firmware.h"
+#include "roots.h"
+
+#include <errno.h>
+#include <string.h>
+#include <sys/reboot.h>
+
+static const char *update_type = NULL;
+static const char *update_data = NULL;
+static int update_length = 0;
+
+int remember_firmware_update(const char *type, const char *data, int length) {
+    if (update_type != NULL || update_data != NULL) {
+        LOGE("Multiple firmware images\n");
+        return -1;
+    }
+
+    update_type = type;
+    update_data = data;
+    update_length = length;
+    return 0;
+}
+
+
+/* Bootloader / Recovery Flow
+ *
+ * On every boot, the bootloader will read the bootloader_message
+ * from flash and check the command field.  The bootloader should
+ * deal with the command field not having a 0 terminator correctly
+ * (so as to not crash if the block is invalid or corrupt).
+ *
+ * The bootloader will have to publish the partition that contains
+ * the bootloader_message to the linux kernel so it can update it.
+ *
+ * if command == "boot-recovery" -> boot recovery.img
+ * else if command == "update-radio" -> update radio image (below)
+ * else if command == "update-hboot" -> update hboot image (below)
+ * else -> boot boot.img (normal boot)
+ *
+ * Radio/Hboot Update Flow
+ * 1. the bootloader will attempt to load and validate the header
+ * 2. if the header is invalid, status="invalid-update", goto #8
+ * 3. display the busy image on-screen
+ * 4. if the update image is invalid, status="invalid-radio-image", goto #8
+ * 5. attempt to update the firmware (depending on the command)
+ * 6. if successful, status="okay", goto #8
+ * 7. if failed, and the old image can still boot, status="failed-update"
+ * 8. write the bootloader_message, leaving the recovery field
+ *    unchanged, updating status, and setting command to
+ *    "boot-recovery"
+ * 9. reboot
+ *
+ * The bootloader will not modify or erase the cache partition.
+ * It is recovery's responsibility to clean up the mess afterwards.
+ */
+
+int maybe_install_firmware_update(const char *send_intent) {
+    if (update_data == NULL || update_length == 0) return 0;
+
+    /* We destroy the cache partition to pass the update image to the
+     * bootloader, so all we can really do afterwards is wipe cache and reboot.
+     * Set up this instruction now, in case we're interrupted while writing.
+     */
+
+    struct bootloader_message boot;
+    memset(&boot, 0, sizeof(boot));
+    strlcpy(boot.command, "boot-recovery", sizeof(boot.command));
+    strlcpy(boot.recovery, "recovery\n--wipe_cache\n", sizeof(boot.command));
+    if (send_intent != NULL) {
+        strlcat(boot.recovery, "--send_intent=", sizeof(boot.recovery));
+        strlcat(boot.recovery, send_intent, sizeof(boot.recovery));
+        strlcat(boot.recovery, "\n", sizeof(boot.recovery));
+    }
+    if (set_bootloader_message(&boot)) return -1;
+
+    int width = 0, height = 0, bpp = 0;
+    char *busy_image = ui_copy_image(
+        BACKGROUND_ICON_FIRMWARE_INSTALLING, &width, &height, &bpp);
+    char *fail_image = ui_copy_image(
+        BACKGROUND_ICON_FIRMWARE_ERROR, &width, &height, &bpp);
+
+    ui_print("Writing %s image...\n", update_type);
+    if (write_update_for_bootloader(
+            update_data, update_length,
+            width, height, bpp, busy_image, fail_image)) {
+        LOGE("Can't write %s image\n(%s)\n", update_type, strerror(errno));
+        format_root_device("CACHE:");  // Attempt to clean cache up, at least.
+        return -1;
+    }
+
+    free(busy_image);
+    free(fail_image);
+
+    /* The update image is fully written, so now we can instruct the bootloader
+     * to install it.  (After doing so, it will come back here, and we will
+     * wipe the cache and reboot into the system.)
+     */
+    snprintf(boot.command, sizeof(boot.command), "update-%s", update_type);
+    if (set_bootloader_message(&boot)) {
+        format_root_device("CACHE:");
+        return -1;
+    }
+
+    reboot(RB_AUTOBOOT);
+
+    // Can't reboot?  WTF?
+    LOGE("Can't reboot\n");
+    return -1;
+}