efi_loader: ensure all block devices are probed

Only probed block devices are available in the UEFI sub-system. Multiple
block devices may be involved in the boot process. So we have to make sure
that all block devices are probed. Another reason is that we store UEFI
variables on the ESP which may be on any block device.

On the sandbox before the patch:

=> efidebug devices
No EFI system partition
Device           Device Path
================ ====================
000000001b027c70 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)
000055d078bc1ae0 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/Uart(0,0,D,D)
000000001b22e0b0 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/MAC(020011223344,1)

After the patch:

=> efidebug devices
No EFI system partition
Device           Device Path
================ ====================
000000001b027c70 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)
000055bdac8ddae0 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/Uart(0,0,D,D)
000000001b230920 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/SD(2)/SD(0)
000000001b233ac0 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/SD(1)/SD(1)
000000001b233b80 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/SD(1)/SD(1)/HD(1,GPT,d0a914ee-a71c-fc1e-73f0-7e302b0e6c20,0x30,0x1)
000000001b234110 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/SD(1)/SD(1)/HD(2,GPT,9330a0ea-8aff-f67a-294c-fa05d60896c3,0x31,0x1)
000000001b22f0e0 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/SD(0)/SD(2)
000000001b238df0 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/MAC(020011223344,1)

Fixes: a9bf024b2933 ("efi_loader: disk: a helper function to create efi_disk objects from udevice")
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

3 files changed, 28 insertions, 1 deletions

diff --git a/include/efi_loader.h b/include/efi_loader.h
index b0d6fff..9611aec 100644
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -531,8 +531,10 @@ void efi_carve_out_dt_rsv(void *fdt);
 void efi_try_purge_kaslr_seed(void *fdt);
 /* Called by bootefi to make console interface available */
 efi_status_t efi_console_register(void);
-/* Called by efi_init_obj_list() to initialize efi_disks */
+/* Called by efi_init_early() to add block devices when probed */
 efi_status_t efi_disk_init(void);
+/* Called by efi_init_obj_list() to proble all block devices */
+efi_status_t efi_disks_register(void);
 /* Called by efi_init_obj_list() to install EFI_RNG_PROTOCOL */
 efi_status_t efi_rng_register(void);
 /* Called by efi_init_obj_list() to install EFI_TCG2_PROTOCOL */
diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c
index f269abf..5feeb52 100644
--- a/lib/efi_loader/efi_disk.c
+++ b/lib/efi_loader/efi_disk.c
@@ -760,3 +760,20 @@ efi_status_t efi_disk_init(void)
 
 	return EFI_SUCCESS;
 }
+
+/**
+ * efi_disks_register() - ensure all block devices are available in UEFI
+ *
+ * The function probes all block devices. As we store UEFI variables on the
+ * EFI system partition this function has to be called before enabling
+ * variable services.
+ */
+efi_status_t efi_disks_register(void)
+{
+	struct udevice *dev;
+
+	uclass_foreach_dev_probe(UCLASS_BLK, dev) {
+	}
+
+	return EFI_SUCCESS;
+}
diff --git a/lib/efi_loader/efi_setup.c b/lib/efi_loader/efi_setup.c
index 751beda..45a9a1d 100644
--- a/lib/efi_loader/efi_setup.c
+++ b/lib/efi_loader/efi_setup.c
@@ -246,6 +246,14 @@ efi_status_t efi_init_obj_list(void)
 	/* Set up console modes */
 	efi_setup_console_size();
 
+	/*
+	 * Probe block devices to find the ESP.
+	 * efi_disks_register() must be called before efi_init_variables().
+	 */
+	ret = efi_disks_register();
+	if (ret != EFI_SUCCESS)
+		goto out;
+
 	/* Initialize variable services */
 	ret = efi_init_variables();
 	if (ret != EFI_SUCCESS)