cmd: Add fsinfo command

Add the fsinfo command to display filesystem statistics including block
size, total blocks, used blocks, and free blocks. Both raw byte counts
and human-readable sizes are shown.

Example output:
  => fsinfo mmc 0:1
  Block size: 4096 bytes
  Total blocks: 16384 (67108864 bytes, 64 MiB)
  Used blocks: 2065 (8458240 bytes, 8.1 MiB)
  Free blocks: 14319 (58650624 bytes, 55.9 MiB)

Co-developed-by: Claude Opus 4.5 <noreply@anthropic.com>
Signed-off-by: Simon Glass <simon.glass@canonical.com>

cmd/Kconfig

@@ -2839,6 +2839,16 @@ config CMD_FS_UUID
 	help
 	  Enables fsuuid command for filesystem UUID.
 
+config CMD_FSINFO
+	bool "fsinfo command"
+	depends on !CMD_JFFS2
+	default y if SANDBOX
+	help
+	  Enables the fsinfo command which prints filesystem statistics
+	  such as block size, total blocks, used blocks and free blocks.
+	  This command conflicts with the JFFS2 fsinfo command, so it
+	  cannot be enabled when JFFS2 support is enabled.
+
 config CMD_LUKS
 	bool "luks command"
 	depends on BLK_LUKS

cmd/fs.c

@@ -152,3 +152,17 @@ U_BOOT_CMD(
 	"    - renames/moves a file/directory in 'dev' on 'interface' from\n"
 	"      'old_path' to 'new_path'"
 );
+
+#ifdef CONFIG_CMD_FSINFO
+static int do_fsinfo_wrapper(struct cmd_tbl *cmdtp, int flag, int argc,
+			     char *const argv[])
+{
+	return do_fs_statfs(cmdtp, flag, argc, argv);
+}
+
+U_BOOT_CMD(fsinfo, 3, 1, do_fsinfo_wrapper,
+	   "Print filesystem information",
+	   "<interface> <dev[:part]>\n"
+	   "    - Print filesystem statistics (block size, total/used/free blocks)"
+);
+#endif