efi: Add uclass for devices provided by UEFI firmware

UCLASS_EFI_LOADER is used for devices created by applications and
drivers loaded by U-Boots UEFI implementation.

This patch provides a new uclass (UCLASS_EFI_MEDIA) to be used for devices
that provided by a UEFI firmware calling U-Boot as an EFI application.

If the two uclasses can be unified, is left to future redesign.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

MAINTAINERS

@@ -713,8 +713,11 @@ W:	https://u-boot.readthedocs.io/en/latest/develop/uefi/u-boot_on_efi.html
 F:	board/efi/efi-x86_app
 F:	configs/efi-x86_app*
 F:	doc/develop/uefi/u-boot_on_efi.rst
+F:	drivers/block/efi-media-uclass.c
+F:	drivers/block/sb_efi_media.c
 F:	lib/efi/efi_app.c
 F:	scripts/build-efi.sh
+F:	test/dm/efi_media.c
 
 EFI PAYLOAD
 M:	Heinrich Schuchardt <xypron.glpk@gmx.de>

arch/sandbox/dts/test.dts

@@ -498,6 +498,10 @@
 		compatible = "sandbox,clk-ccf";
 	};
 
+	efi-media {
+		compatible = "sandbox,efi-media";
+	};
+
 	eth@10002000 {
 		compatible = "sandbox,eth";
 		reg = <0x10002000 0x1000>;

disk/part.c

@@ -296,8 +296,11 @@ static void print_part_header(const char *type, struct blk_desc *dev_desc)
 	case IF_TYPE_VIRTIO:
 		puts("VirtIO");
 		break;
+	case IF_TYPE_EFI_MEDIA:
+		puts("EFI");
+		break;
 	default:
-		puts ("UNKNOWN");
+		puts("UNKNOWN");
 		break;
 	}
 	printf (" device %d  --   Partition Type: %s\n\n",

drivers/block/Kconfig

@@ -61,6 +61,29 @@ config TPL_BLOCK_CACHE
 	help
 	  This option enables the disk-block cache in TPL
 
+config EFI_MEDIA
+	bool "Support EFI media drivers"
+	default y if EFI || SANDBOX
+	help
+	  Enable this to support media devices on top of UEFI. This enables
+	  just the uclass so you also need a specific driver to make this do
+	  anything.
+
+	  For sandbox there is a test driver.
+
+if EFI_MEDIA
+
+config EFI_MEDIA_SANDBOX
+	bool "Sandbox EFI media driver"
+	depends on SANDBOX
+	default y
+	help
+	  Enables a simple sandbox media driver, used for testing just the
+	  EFI_MEDIA uclass. It does not do anything useful, since sandbox does
+	  not actually support running on top of UEFI.
+
+endif  # EFI_MEDIA
+
 config IDE
 	bool "Support IDE controllers"
 	select HAVE_BLOCK_DEVICE

drivers/block/Makefile

@@ -14,3 +14,6 @@ obj-$(CONFIG_IDE) += ide.o
 endif
 obj-$(CONFIG_SANDBOX) += sandbox.o
 obj-$(CONFIG_$(SPL_TPL_)BLOCK_CACHE) += blkcache.o
+
+obj-$(CONFIG_EFI_MEDIA) += efi-media-uclass.o
+obj-$(CONFIG_EFI_MEDIA_SANDBOX) += sb_efi_media.o

drivers/block/blk-uclass.c

@@ -28,6 +28,7 @@ static const char *if_typename_str[IF_TYPE_COUNT] = {
 	[IF_TYPE_SATA]		= "sata",
 	[IF_TYPE_HOST]		= "host",
 	[IF_TYPE_NVME]		= "nvme",
+	[IF_TYPE_EFI_MEDIA]	= "efi",
 	[IF_TYPE_EFI_LOADER]	= "efiloader",
 	[IF_TYPE_VIRTIO]	= "virtio",
 	[IF_TYPE_PVBLOCK]	= "pvblock",
@@ -44,6 +45,7 @@ static enum uclass_id if_type_uclass_id[IF_TYPE_COUNT] = {
 	[IF_TYPE_SATA]		= UCLASS_AHCI,
 	[IF_TYPE_HOST]		= UCLASS_ROOT,
 	[IF_TYPE_NVME]		= UCLASS_NVME,
+	[IF_TYPE_EFI_MEDIA]	= UCLASS_EFI_MEDIA,
 	[IF_TYPE_EFI_LOADER]	= UCLASS_EFI_LOADER,
 	[IF_TYPE_VIRTIO]	= UCLASS_VIRTIO,
 	[IF_TYPE_PVBLOCK]	= UCLASS_PVBLOCK,

drivers/block/efi-media-uclass.c

@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Uclass for EFI media devices
+ *
+ * Copyright 2021 Google LLC
+ */
+
+#include <common.h>
+#include <dm.h>
+
+UCLASS_DRIVER(efi_media) = {
+	.id		= UCLASS_EFI_MEDIA,
+	.name		= "efi_media",
+	.flags		= DM_UC_FLAG_SEQ_ALIAS,
+};

drivers/block/sb_efi_media.c

@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * EFI_MEDIA driver for sandbox
+ *
+ * Copyright 2021 Google LLC
+ */
+
+#include <common.h>
+#include <dm.h>
+
+static const struct udevice_id sandbox_efi_media_ids[] = {
+	{ .compatible = "sandbox,efi-media" },
+	{ }
+};
+
+U_BOOT_DRIVER(sandbox_efi_media) = {
+	.name		= "sandbox_efi_media",
+	.id		= UCLASS_EFI_MEDIA,
+	.of_match	= sandbox_efi_media_ids,
+};

include/blk.h

@@ -37,6 +37,7 @@ enum if_type {
 	IF_TYPE_EFI_LOADER,
 	IF_TYPE_PVBLOCK,
 	IF_TYPE_VIRTIO,
+	IF_TYPE_EFI_MEDIA,
 
 	IF_TYPE_COUNT,			/* Number of interface types */
 };

include/dm/uclass-id.h

@@ -49,6 +49,7 @@ enum uclass_id {
 	UCLASS_DSA,		/* Distributed (Ethernet) Switch Architecture */
 	UCLASS_ECDSA,		/* Elliptic curve cryptographic device */
 	UCLASS_EFI_LOADER,	/* Devices created by UEFI applications */
+	UCLASS_EFI_MEDIA,	/* Devices provided by UEFI firmware */
 	UCLASS_ETH,		/* Ethernet device */
 	UCLASS_ETH_PHY,		/* Ethernet PHY device */
 	UCLASS_FIRMWARE,	/* Firmware */

test/dm/Makefile

@@ -37,6 +37,7 @@ obj-$(CONFIG_DMA) += dma.o
 obj-$(CONFIG_VIDEO_MIPI_DSI) += dsi_host.o
 obj-$(CONFIG_DM_DSA) += dsa.o
 obj-$(CONFIG_ECDSA_VERIFY) += ecdsa.o
+obj-$(CONFIG_EFI_MEDIA_SANDBOX) += efi_media.o
 obj-$(CONFIG_DM_ETH) += eth.o
 ifneq ($(CONFIG_EFI_PARTITION),)
 obj-$(CONFIG_FASTBOOT_FLASH_MMC) += fastboot.o

test/dm/efi_media.c

@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Test for EFI_MEDIA uclass
+ *
+ * Copyright 2021 Google LLC
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <asm/test.h>
+#include <dm/test.h>
+#include <test/test.h>
+#include <test/ut.h>
+
+/* Test that we can use the EFI_MEDIA uclass */
+static int dm_test_efi_media(struct unit_test_state *uts)
+{
+	struct udevice *dev;
+
+	ut_assertok(uclass_first_device_err(UCLASS_EFI_MEDIA, &dev));
+
+	return 0;
+}
+DM_TEST(dm_test_efi_media, UT_TESTF_SCAN_PDATA | UT_TESTF_SCAN_FDT);