[RFC PATCH 15/20] boot: bootmeth: openwrt: implement boot via bootm storage path

[Daniel Golle]

Implement openwrt_boot() to boot a discovered OpenWrt FIT image:

1. Get the block interface name via blk_get_devtype() and construct
   the dev_part_str (e.g. "0:3") from the block descriptor and
   bootflow partition number
2. Initialise an image_loader for block devices via
   image_loader_init_blk(), with alloc_ptr set to image_load_addr
3. Optionally read the 'bootconf' env variable and pass it as
   '#config' in bmi.addr_img for FIT configuration selection
4. Call bootm_run() which runs the full bootm state machine:
   START -> FINDOS -> FINDOTHER -> LOADOS -> OS_PREP -> OS_GO

The image_loader handles on-demand reading of the FIT metadata and
sub-images (kernel, FDT) directly from the raw partition. The
existing cleanup call in bootm_run_states() releases the loader just
before OS_GO. If bootm_run() returns (boot failure), cleanup is
called explicitly.

This completes the core block-device boot path for bootmeth_openwrt.

Signed-off-by: Daniel Golle <daniel at makrotopia.org>
---
 boot/bootmeth_openwrt.c | 37 ++++++++++++++++++++++++++++++++++++-
 1 file changed, 36 insertions(+), 1 deletion(-)

diff --git a/boot/bootmeth_openwrt.c b/boot/bootmeth_openwrt.c
index 08c3f98957a..82f39c17d7f 100644
--- a/boot/bootmeth_openwrt.c
+++ b/boot/bootmeth_openwrt.c
@@ -13,6 +13,8 @@
 #include <bootm.h>
 #include <bootmeth.h>
 #include <dm.h>
+#include <env.h>
+#include <image.h>
 #include <image-loader.h>
 #include <malloc.h>
 #include <mapmem.h>
@@ -73,7 +75,40 @@ static int openwrt_read_bootflow(struct udevice *dev, struct bootflow *bflow)
 
 static int openwrt_boot(struct udevice *dev, struct bootflow *bflow)
 {
-	return log_msg_ret("nyi", -ENOSYS);
+	struct blk_desc *desc = dev_get_uclass_plat(bflow->blk);
+	const char *ifname = blk_get_devtype(bflow->blk);
+	struct image_loader ldr = {};
+	struct bootm_info bmi;
+	char dev_part_str[32];
+	char addr_img[64];
+	const char *conf;
+	int ret;
+
+	snprintf(dev_part_str, sizeof(dev_part_str), "%d:%d",
+		 desc->devnum, bflow->part);
+
+	ret = image_loader_init_blk(&ldr, ifname, dev_part_str);
+	if (ret)
+		return log_msg_ret("ldr", ret);
+
+	ldr.alloc_ptr = image_load_addr;
+
+	bootm_init(&bmi);
+	bmi.loader = &ldr;
+
+	/* FIT config selection via #conf suffix */
+	conf = env_get("bootconf");
+	if (conf) {
+		snprintf(addr_img, sizeof(addr_img), "#%s", conf);
+		bmi.addr_img = addr_img;
+	}
+
+	ret = bootm_run(&bmi);
+
+	/* Clean up if bootm_run() returned (i.e. boot failed) */
+	image_loader_cleanup(&ldr);
+
+	return log_msg_ret("run", ret);
 }
 
 static int openwrt_bootmeth_bind(struct udevice *dev)
-- 
2.53.0