[Concept,04/20] efi: Add a way to show media devices

Message ID 20250828020732.981415-5-sjg@u-boot.org
State New
Headers
Series efi: App and devicetree improvements |

Commit Message

Simon Glass Aug. 28, 2025, 2:07 a.m. UTC
  From: Simon Glass <sjg@chromium.org>

Add a new 'efidebug media' subcommand to show media devices and their
device-paths.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 cmd/efidebug.c             | 43 ++++++++++++++++++++++++++++++++++++++
 doc/usage/cmd/efidebug.rst | 21 ++++++++++++++++++-
 2 files changed, 63 insertions(+), 1 deletion(-)
  

Patch

diff --git a/cmd/efidebug.c b/cmd/efidebug.c
index 1515a508e2d..1d943113054 100644
--- a/cmd/efidebug.c
+++ b/cmd/efidebug.c
@@ -8,6 +8,8 @@ 
 #include <charset.h>
 #include <command.h>
 #include <dm/device.h>
+#include <dm/uclass.h>
+#include <efi.h>
 #include <efi_device_path.h>
 #include <efi_dt_fixup.h>
 #include <efi_load_initrd.h>
@@ -1604,6 +1606,43 @@  static int do_efi_test(struct cmd_tbl *cmdtp, int flag,
 	return cp->cmd(cmdtp, flag, argc, argv);
 }
 
+/**
+ * do_efi_show_media() - show EFI media devices
+ *
+ * @cmdtp:	Command table
+ * @flag:	Command flag
+ * @argc:	Number of arguments
+ * @argv:	Argument array
+ * Return:	CMD_RET_SUCCESS on success, CMD_RET_FAILURE on failure
+ *
+ * Implement efidebug "media" sub-command.
+ * Show all EFI media devices and their device paths.
+ */
+static int do_efi_show_media(struct cmd_tbl *cmdtp, int flag,
+			     int argc, char *const argv[])
+{
+	struct udevice *dev;
+	struct uclass *uc;
+	int ret;
+
+	ret = uclass_get(UCLASS_EFI_MEDIA, &uc);
+	if (ret) {
+		printf("Cannot get EFI media uclass: (err=%dE)\n", ret);
+		return CMD_RET_FAILURE;
+	}
+
+	printf("Device               Device Path\n");
+	printf("-------------------  -----------\n");
+
+	uclass_foreach_dev(dev, uc) {
+		struct efi_media_plat *plat = dev_get_plat(dev);
+
+		printf("%-20s %pD\n", dev->name, plat->device_path);
+	}
+
+	return CMD_RET_SUCCESS;
+}
+
 /**
  * do_efi_query_info() - QueryVariableInfo EFI service
  *
@@ -1670,6 +1709,8 @@  static struct cmd_tbl cmd_efidebug_sub[] = {
 	U_BOOT_CMD_MKENT(images, CONFIG_SYS_MAXARGS, 1, do_efi_show_images,
 			 "", ""),
 	U_BOOT_CMD_MKENT(log, CONFIG_SYS_MAXARGS, 1, do_efi_show_log, "", ""),
+	U_BOOT_CMD_MKENT(media, CONFIG_SYS_MAXARGS, 1, do_efi_show_media,
+			 "", ""),
 	U_BOOT_CMD_MKENT(memmap, CONFIG_SYS_MAXARGS, 1, do_efi_show_memmap,
 			 "", ""),
 	U_BOOT_CMD_MKENT(tables, CONFIG_SYS_MAXARGS, 1, do_efi_show_tables,
@@ -1772,6 +1813,8 @@  U_BOOT_LONGHELP(efidebug,
 	"  - show loaded images\n"
 	"efidebug log\n"
 	"  - show UEFI log\n"
+	"efidebug media\n"
+	"  - show EFI media devices\n"
 	"efidebug memmap\n"
 	"  - show UEFI memory map\n"
 	"efidebug tables\n"
diff --git a/doc/usage/cmd/efidebug.rst b/doc/usage/cmd/efidebug.rst
index 5eca4079f82..90e0b9c4546 100644
--- a/doc/usage/cmd/efidebug.rst
+++ b/doc/usage/cmd/efidebug.rst
@@ -14,6 +14,7 @@  Synopsis
 ::
 
     efidebug log
+    efidebug media
 
 Description
 -----------
@@ -21,7 +22,7 @@  Description
 The *efidebug* command provides access to debugging features for the EFI-loader
 subsystem.
 
-Only one of the subcommands are documented at present.
+Only two of the subcommands are documented at present.
 
 efidebug log
 ~~~~~~~~~~~~
@@ -30,10 +31,28 @@  This shows a log of EFI boot-services calls which have been handled since U-Boot
 started. This can be useful to see what the app is doing, or even what U-Boot
 itself has called.
 
+efidebug media
+~~~~~~~~~~~~~~
+
+This shows a list of all EFI media devices and their corresponding device paths.
+Each EFI media device represents a block device that was discovered through EFI
+boot services, such as hard drives, USB storage, or other bootable media. The
+device path shows the EFI device path for each device, which can be useful for
+debugging boot issues or understanding the system topology.
+
 
 Example
 -------
 
+This shows checking the EFI media devices::
+
+   => efidebug media
+  Device                 Device Path
+  ------                 -----------
+    efi_media_1          PciRoot(0x0)/Pci(0x3,0x0)/Sata(0x0,0xFFFF,0x0)
+    efi_media_2          PciRoot(0x0)/Pci(0x5,0x0)
+
+
 This shows checking the log, then using 'efidebug tables' to fully set up the
 EFI-loader subsystem, then checking the log again::