x86: zboot: Set environment variables for image locations

At present it is not possible to tell from a script where the setup block
is, or where the image was loaded to. Add environment variables for this.
Signed-off-by: NSimon Glass <sjg@chromium.org>
Reviewed-by: NWolfgang Wallner <wolfgang.wallner@br-automation.com>
Reviewed-by: NBin Meng <bmeng.cn@gmail.com>

README

@@ -3425,6 +3425,10 @@ List of environment variables (most likely not complete):
   mempos	- Index position of the last match found by the 'ms' command,
 		  in units of the size (.b, .w, .l) of the search
 
+  zbootbase	- (x86 only) Base address of the bzImage 'setup' block
+
+  zbootaddr	- (x86 only) Address of the loaded bzImage, typically
+		  BZIMAGE_LOAD_ADDR which is 0x100000
 
 The following image location variables contain the location of images
 used in booting. The "Image" column gives the role of the image and is

arch/x86/lib/zimage.c

@@ -382,6 +382,9 @@ static int do_zboot_load(struct cmd_tbl *cmdtp, int flag, int argc,
 		return CMD_RET_FAILURE;
 	}
 	state.base_ptr = base_ptr;
+	if (env_set_hex("zbootbase", (ulong)base_ptr) ||
+	    env_set_hex("zbootaddr", state.load_address))
+		return CMD_RET_FAILURE;
 
 	return 0;
 }