Add 'load_android' command to load Android images.

Android kernel images include a header that specifies addresses and
kernel size. This patch adds a command to load these images from
storage without specifying the size or address of them, and parsing
them from the header instead.

Bug: 31636643
Change-Id: I84a9cf82cff78ce2299b1981c4f6f9a5720e4d0d

cmd/Kconfig

@@ -743,6 +743,15 @@ config CMD_LOADS
 	help
 	  Load an S-Record file over serial line
 
+config CMD_LOAD_ANDROID
+	bool "load_android"
+	default n
+	depends on ANDROID_BOOT_IMAGE
+	help
+	  Load an Android Boot image from storage. The Android Boot images
+	  define the size and kernel address on the header, which are used by
+	  this command.
+
 config CMD_MMC
 	bool "mmc"
 	help

cmd/Makefile

@@ -76,6 +76,7 @@ obj-$(CONFIG_LED_STATUS_CMD) += legacy_led.o
 obj-$(CONFIG_CMD_LED) += led.o
 obj-$(CONFIG_CMD_LICENSE) += license.o
 obj-y += load.o
+obj-$(CONFIG_CMD_LOAD_ANDROID) += load_android.o
 obj-$(CONFIG_LOGBUFFER) += log.o
 obj-$(CONFIG_ID_EEPROM) += mac.o
 obj-$(CONFIG_CMD_MD5SUM) += md5sum.o

cmd/load_android.c

@@ -0,0 +1,85 @@
+/*
+  * Copyright (C) 2008 The Android Open Source Project
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <common.h>
+#include <command.h>
+#include <mapmem.h>
+
+static int do_load_android(cmd_tbl_t *cmdtp, int flag, int argc,
+			   char * const argv[])
+{
+	int boot_partition;
+	unsigned long load_address, blk_cnt, blk_read;
+	int ret = CMD_RET_SUCCESS;
+	char *addr_arg_endp, *addr_str;
+	void *buf;
+	struct blk_desc *dev_desc;
+	disk_partition_t part_info;
+
+	if (argc < 2)
+		return CMD_RET_USAGE;
+	if (argc > 4)
+		return CMD_RET_USAGE;
+
+	if (argc >= 4) {
+		load_address = simple_strtoul(argv[3], &addr_arg_endp, 16);
+		if (addr_arg_endp == argv[3] || *addr_arg_endp != '\0')
+			return CMD_RET_USAGE;
+	} else {
+		addr_str = env_get("loadaddr");
+		if (addr_str != NULL)
+			load_address = simple_strtoul(addr_str, NULL, 16);
+		else
+			load_address = CONFIG_SYS_LOAD_ADDR;
+	}
+
+	boot_partition = blk_get_device_part_str(argv[1],
+	                                         (argc >= 3) ? argv[2] : NULL,
+	                                         &dev_desc, &part_info, 1);
+	if (boot_partition < 0)
+		return CMD_RET_FAILURE;
+
+	/* We don't know the size of the Android image before reading the header
+	 * so we don't limit the size of the mapped memory. */
+	buf = map_sysmem(load_address, 0 /* size */);
+
+	/* Read the Android header first and then read the rest. */
+	if (blk_dread(dev_desc, part_info.start, 1, buf) != 1) {
+		ret = CMD_RET_FAILURE;
+	}
+
+	if (ret == CMD_RET_SUCCESS && android_image_check_header(buf) != 0) {
+		printf("\n** Invalid Android Image header on %s %d:%d **\n",
+		       argv[1], dev_desc->devnum, boot_partition);
+		ret = CMD_RET_FAILURE;
+	}
+	if (ret == CMD_RET_SUCCESS) {
+		blk_cnt = (android_image_get_end(buf) - (ulong)buf +
+		           part_info.blksz - 1) / part_info.blksz;
+		printf("\nLoading Android Image (%lu blocks) to 0x%lx... ",
+		       blk_cnt, load_address);
+		blk_read = blk_dread(dev_desc, part_info.start, blk_cnt, buf);
+	}
+
+	unmap_sysmem(buf);
+	if (ret != CMD_RET_SUCCESS)
+		return ret;
+
+	printf("%lu blocks read: %s\n",
+	       blk_read, (blk_read == blk_cnt) ? "OK" : "ERROR");
+	return (blk_read == blk_cnt) ? CMD_RET_SUCCESS : CMD_RET_FAILURE;
+}
+
+
+#if defined(CONFIG_CMD_LOAD_ANDROID)
+U_BOOT_CMD(
+	load_android, 4, 0, do_load_android,
+	"load Android Boot image from storage.",
+	"<interface> [<dev[:part]> [<addr>]]\n"
+	"    - Load a binary Android Boot image from the partition 'part' on\n"
+	"      device type 'interface' instance 'dev' to address 'addr'."
+);
+#endif	/* CONFIG_CMD_LOAD_ANDROID */