bootmeth_efi: Support PXE booting

Finish off the implementation so it is possible to boot an EFI app over
a network.

Series-changes: 3
- Add new patch to support PXE booting
- Rebase on Tom's tree (i.e. without the pointers/addresses series)
  https://patchwork.ozlabs.org/project/uboot/list/?series=436241

Series-to: u-boot
Series-cc: ilias, heinrich, trini
Series-version: 3
Series-links: 436308 1:428768
Cover-letter:
efi: Start to chip away at the EFI workaround
At present there is a function, efi_set_bootdev(), which is used in
various places to tell the EFI loader which device a file came from.

With bootstd, this information is available in the bootflow.

This little series provides a way for bootstd to provide the bootflow to
the EFI loader, so that it is able to select the correct paths.

For now only the EFI bootmeth is updated.
END

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

boot/bootmeth_efi.c

@@ -52,40 +52,6 @@ static bool bootmeth_uses_network(struct bootflow *bflow)
 	    device_get_uclass_id(media) == UCLASS_ETH;
 }
 
-static void set_efi_bootdev(struct blk_desc *desc, struct bootflow *bflow)
-{
-	const struct udevice *media_dev;
-	int size = bflow->size;
-	const char *dev_name;
-	char devnum_str[9];
-	char dirname[200];
-	char *last_slash;
-
-	/*
-	 * This is a horrible hack to tell EFI about this boot device. Once we
-	 * unify EFI with the rest of U-Boot we can clean this up. The same hack
-	 * exists in multiple places, e.g. in the fs, tftp and load commands.
-	 *
-	 * Once we can clean up the EFI code to make proper use of driver model,
-	 * this can go away.
-	 */
-	media_dev = dev_get_parent(bflow->dev);
-	snprintf(devnum_str, sizeof(devnum_str), "%x:%x",
-		 desc ? desc->devnum : dev_seq(media_dev),
-		 bflow->part);
-
-	strlcpy(dirname, bflow->fname, sizeof(dirname));
-	last_slash = strrchr(dirname, '/');
-	if (last_slash)
-		*last_slash = '\0';
-
-	dev_name = device_get_uclass_id(media_dev) == UCLASS_MASS_STORAGE ?
-		 "usb" : blk_get_uclass_name(device_get_uclass_id(media_dev));
-	log_debug("setting bootdev %s, %s, %s, %p, %x\n",
-		  dev_name, devnum_str, bflow->fname, bflow->buf, size);
-	efi_set_bootdev(dev_name, devnum_str, bflow->fname, bflow->buf, size);
-}
-
 static int efiload_read_file(struct bootflow *bflow, ulong addr)
 {
 	struct blk_desc *desc = NULL;
@@ -103,8 +69,6 @@ static int efiload_read_file(struct bootflow *bflow, ulong addr)
 		return log_msg_ret("read", ret);
 	bflow->buf = map_sysmem(addr, bflow->size);
 
-	set_efi_bootdev(desc, bflow);
-
 	return 0;
 }
 
@@ -246,6 +210,7 @@ static int distro_efi_read_bootflow_net(struct bootflow *bflow)
 	if (size <= 0)
 		return log_msg_ret("sz", -EINVAL);
 	bflow->size = size;
+	bflow->buf = map_sysmem(addr, size);
 
 	/* bootfile should be setup by dhcp */
 	bootfile_name = env_get("bootfile");
@@ -253,10 +218,6 @@ static int distro_efi_read_bootflow_net(struct bootflow *bflow)
 		return log_msg_ret("bootfile_name", ret);
 	bflow->fname = strdup(bootfile_name);
 
-	/* do the hideous EFI hack */
-	efi_set_bootdev("Net", "", bflow->fname, map_sysmem(addr, 0),
-			bflow->size);
-
 	/* read the DT file also */
 	fdt_addr_str = env_get("fdt_addr_r");
 	if (!fdt_addr_str)
@@ -330,29 +291,10 @@ static int distro_efi_boot(struct udevice *dev, struct bootflow *bflow)
 		if (bflow->flags & ~BOOTFLOWF_USE_BUILTIN_FDT)
 			fdt = bflow->fdt_addr;
 
-	} else {
-		/*
-		 * This doesn't actually work for network devices:
-		 *
-		 * do_bootefi_image() No UEFI binary known at 0x02080000
-		 *
-		 * But this is the same behaviour for distro boot, so it can be
-		 * fixed here.
-		 */
-		fdt = env_get_hex("fdt_addr_r", 0);
 	}
 
-	if (bflow->flags & BOOTFLOWF_USE_BUILTIN_FDT) {
-		log_debug("Booting with built-in fdt\n");
-		if (efi_binary_run(map_sysmem(kernel, 0), bflow->size,
-				   EFI_FDT_USE_INTERNAL))
-			return log_msg_ret("run", -EINVAL);
-	} else {
-		log_debug("Booting with external fdt\n");
-		if (efi_binary_run(map_sysmem(kernel, 0), bflow->size,
-				   map_sysmem(fdt, 0)))
-			return log_msg_ret("run", -EINVAL);
-	}
+	if (efi_bootflow_run(bflow))
+		return log_msg_ret("run", -EINVAL);
 
 	return 0;
 }

include/efi_loader.h

@@ -20,6 +20,7 @@
 #include <linux/oid_registry.h>
 
 struct blk_desc;
+struct bootflow;
 struct jmp_buf_data;
 
 #if CONFIG_IS_ENABLED(EFI_LOADER)
@@ -578,6 +579,15 @@ efi_status_t efi_install_fdt(void *fdt);
 efi_status_t do_bootefi_exec(efi_handle_t handle, void *load_options);
 /* Run loaded UEFI image with given fdt */
 efi_status_t efi_binary_run(void *image, size_t size, void *fdt);
+
+/**
+ * efi_bootflow_run() - Run a bootflow containing an EFI application
+ *
+ * @bootflow: Bootflow to run
+ * Return: Status code, something went wrong
+ */
+efi_status_t efi_bootflow_run(struct bootflow *bootflow);
+
 /* Initialize variable services */
 efi_status_t efi_init_variables(void);
 /* Notify ExitBootServices() is called */

lib/efi_loader/efi_bootbin.c

@@ -6,13 +6,16 @@
 
 #define LOG_CATEGORY LOGC_EFI
 
+#include <bootflow.h>
 #include <charset.h>
+#include <dm.h>
 #include <efi.h>
 #include <efi_loader.h>
 #include <env.h>
 #include <image.h>
 #include <log.h>
 #include <malloc.h>
+#include <mapmem.h>
 
 static struct efi_device_path *bootefi_image_path;
 static struct efi_device_path *bootefi_device_path;
@@ -44,12 +47,64 @@ void efi_clear_bootdev(void)
 	image_size = 0;
 }
 
+/**
+ * calculate_paths() - Calculate the device and image patch given a device
+ *
+ * @dev:		device, e.g. "MMC"
+ * @devnr:		number of the device, e.g. "1:2"
+ * @path:		path to file loaded
+ * @device_pathp:	returns EFI device path
+ * @image_pathp:	returns EFI image path
+ * Return EFI_SUCCESS on success, else error code
+ */
+static efi_status_t calculate_paths(const char *dev, const char *devnr,
+				    const char *path,
+				    struct efi_device_path **device_pathp,
+				    struct efi_device_path **image_pathp)
+{
+	struct efi_device_path *image, *device;
+	efi_status_t ret;
+
+#if IS_ENABLED(CONFIG_NETDEVICES)
+	if (!strcmp(dev, "Net") || !strcmp(dev, "Http")) {
+		ret = efi_net_set_dp(dev, devnr);
+		if (ret != EFI_SUCCESS)
+			return ret;
+	}
+#endif
+
+	ret = efi_dp_from_name(dev, devnr, path, &device, &image);
+	if (ret != EFI_SUCCESS)
+		return ret;
+
+	*device_pathp = device;
+	if (image) {
+		/* FIXME: image should not contain device */
+		struct efi_device_path *image_tmp = image;
+
+		efi_dp_split_file_path(image, &device, &image);
+		efi_free_pool(image_tmp);
+	}
+	*image_pathp = image;
+	log_debug("- boot device %pD\n", device);
+	if (image)
+		log_debug("- image %pD\n", image);
+
+	return EFI_SUCCESS;
+}
+
 /**
  * efi_set_bootdev() - set boot device
  *
  * This function is called when a file is loaded, e.g. via the 'load' command.
  * We use the path to this file to inform the UEFI binary about the boot device.
  *
+ * For a valid image, it sets:
+ *    - image_addr to the provided buffer
+ *    - image_size to the provided buffer_size
+ *    - bootefi_device_path to the EFI device-path
+ *    - bootefi_image_path to the EFI image-path
+ *
  * @dev:		device, e.g. "MMC"
  * @devnr:		number of the device, e.g. "1:2"
  * @path:		path to file loaded
@@ -59,7 +114,6 @@ void efi_clear_bootdev(void)
 void efi_set_bootdev(const char *dev, const char *devnr, const char *path,
 		     void *buffer, size_t buffer_size)
 {
-	struct efi_device_path *device, *image;
 	efi_status_t ret;
 
 	log_debug("dev=%s, devnr=%s, path=%s, buffer=%p, size=%zx\n", dev,
@@ -93,34 +147,12 @@ void efi_set_bootdev(const char *dev, const char *devnr, const char *path,
 	image_addr = buffer;
 	image_size = buffer_size;
 
-#if IS_ENABLED(CONFIG_NETDEVICES)
-	if (!strcmp(dev, "Net") || !strcmp(dev, "Http")) {
-		ret = efi_net_set_dp(dev, devnr);
-		if (ret != EFI_SUCCESS)
-			goto error;
+	ret = calculate_paths(dev, devnr, path, &bootefi_device_path,
+			      &bootefi_image_path);
+	if (ret) {
+		log_debug("- efi_dp_from_name() failed, err=%lx\n", ret);
+		efi_clear_bootdev();
 	}
-#endif
-
-	ret = efi_dp_from_name(dev, devnr, path, &device, &image);
-	if (ret != EFI_SUCCESS)
-		goto error;
-
-	bootefi_device_path = device;
-	if (image) {
-		/* FIXME: image should not contain device */
-		struct efi_device_path *image_tmp = image;
-
-		efi_dp_split_file_path(image, &device, &image);
-		efi_free_pool(image_tmp);
-	}
-	bootefi_image_path = image;
-	log_debug("- boot device %pD\n", device);
-	if (image)
-		log_debug("- image %pD\n", image);
-	return;
-error:
-	log_debug("- efi_dp_from_name() failed, err=%lx\n", ret);
-	efi_clear_bootdev();
 }
 
 /**
@@ -128,42 +160,21 @@ error:
  *
  * @source_buffer:	memory address of the UEFI image
  * @source_size:	size of the UEFI image
+ * @device:		EFI device-path
+ * @image:		EFI image-path
  * Return:		status code
  */
-efi_status_t efi_run_image(void *source_buffer, efi_uintn_t source_size)
+static efi_status_t efi_run_image(void *source_buffer, efi_uintn_t source_size,
+				  struct efi_device_path *device,
+				  struct efi_device_path *image)
 {
-	efi_handle_t mem_handle = NULL, handle;
-	struct efi_device_path *file_path = NULL;
-	struct efi_device_path *msg_path;
+	efi_handle_t handle;
+	struct efi_device_path *msg_path, *file_path;
 	efi_status_t ret;
 	u16 *load_options;
 
-	if (!bootefi_device_path || !bootefi_image_path) {
-		log_debug("Not loaded from disk\n");
-		/*
-		 * Special case for efi payload not loaded from disk,
-		 * such as 'bootefi hello' or for example payload
-		 * loaded directly into memory via JTAG, etc:
-		 */
-		file_path = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE,
-					    (uintptr_t)source_buffer,
-					    source_size);
-		/*
-		 * Make sure that device for device_path exist
-		 * in load_image(). Otherwise, shell and grub will fail.
-		 */
-		ret = efi_install_multiple_protocol_interfaces(&mem_handle,
-							       &efi_guid_device_path,
-							       file_path, NULL);
-		if (ret != EFI_SUCCESS)
-			goto out;
-		msg_path = file_path;
-	} else {
-		file_path = efi_dp_concat(bootefi_device_path,
-					  bootefi_image_path, 0);
-		msg_path = bootefi_image_path;
-		log_debug("Loaded from disk\n");
-	}
+	file_path = efi_dp_concat(device, image, 0);
+	msg_path = image;
 
 	log_info("Booting %pD\n", msg_path);
 
@@ -182,19 +193,45 @@ efi_status_t efi_run_image(void *source_buffer, efi_uintn_t source_size)
 	ret = do_bootefi_exec(handle, load_options);
 
 out:
-	if (mem_handle) {
-		efi_status_t r;
-
-		r = efi_uninstall_multiple_protocol_interfaces(
-			mem_handle, &efi_guid_device_path, file_path, NULL);
-		if (r != EFI_SUCCESS)
-			log_err("Uninstalling protocol interfaces failed\n");
-	}
-	efi_free_pool(file_path);
 
 	return ret;
 }
 
+/**
+ * efi_binary_run_() - run loaded UEFI image
+ *
+ * @image_ptr:	memory address of the UEFI image
+ * @size:	size of the UEFI image
+ * @fdt:	device-tree
+ * @device:	EFI device-path
+ * @image:	EFI image-path
+ *
+ * Execute an EFI binary image loaded at @image.
+ * @size may be zero if the binary is loaded with U-Boot load command.
+ *
+ * Return:	status code
+ */
+static efi_status_t _efi_binary_run(void *image_ptr, size_t size, void *fdt,
+				    struct efi_device_path *device,
+				    struct efi_device_path *image)
+{
+	efi_status_t ret;
+
+	/* Initialize EFI drivers */
+	ret = efi_init_obj_list();
+	if (ret != EFI_SUCCESS) {
+		log_err("Error: Cannot initialize UEFI sub-system, r = %lu\n",
+			ret & ~EFI_ERROR_MASK);
+		return -1;
+	}
+
+	ret = efi_install_fdt(fdt);
+	if (ret != EFI_SUCCESS)
+		return ret;
+
+	return efi_run_image(image_ptr, size, device, image);
+}
+
 /**
  * efi_binary_run() - run loaded UEFI image
  *
@@ -209,19 +246,116 @@ out:
  */
 efi_status_t efi_binary_run(void *image, size_t size, void *fdt)
 {
+	efi_handle_t mem_handle = NULL;
+	struct efi_device_path *file_path = NULL;
 	efi_status_t ret;
 
-	/* Initialize EFI drivers */
-	ret = efi_init_obj_list();
-	if (ret != EFI_SUCCESS) {
-		log_err("Error: Cannot initialize UEFI sub-system, r = %lu\n",
-			ret & ~EFI_ERROR_MASK);
-		return -1;
+	if (!bootefi_device_path || !bootefi_image_path) {
+		log_debug("Not loaded from disk\n");
+		/*
+		 * Special case for efi payload not loaded from disk,
+		 * such as 'bootefi hello' or for example payload
+		 * loaded directly into memory via JTAG, etc:
+		 */
+		file_path = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE,
+					    (uintptr_t)image, size);
+		/*
+		 * Make sure that device for device_path exist
+		 * in load_image(). Otherwise, shell and grub will fail.
+		 */
+		ret = efi_install_multiple_protocol_interfaces(&mem_handle,
+							       &efi_guid_device_path,
+							       file_path, NULL);
+		if (ret != EFI_SUCCESS)
+			goto out;
+	} else {
+		log_debug("Loaded from disk\n");
 	}
 
-	ret = efi_install_fdt(fdt);
-	if (ret != EFI_SUCCESS)
-		return ret;
+	ret = _efi_binary_run(image, size, fdt, bootefi_device_path,
+			      bootefi_image_path);
+out:
+	if (mem_handle) {
+		efi_status_t r;
 
-	return efi_run_image(image, size);
+		r = efi_uninstall_multiple_protocol_interfaces(mem_handle,
+					&efi_guid_device_path, file_path, NULL);
+		if (r != EFI_SUCCESS)
+			log_err("Uninstalling protocol interfaces failed\n");
+	}
+	efi_free_pool(file_path);
+
+	return ret;
 }
+
+/**
+ * calc_dev_name() - Calculate the device name to give to EFI
+ *
+ * If not supported, this shows an error.
+ *
+ * Return name, or NULL if not supported
+ */
+static const char *calc_dev_name(struct bootflow *bflow)
+{
+	const struct udevice *media_dev;
+
+	media_dev = dev_get_parent(bflow->dev);
+
+	if (!bflow->blk) {
+		if (device_get_uclass_id(media_dev) == UCLASS_ETH)
+			return "Net";
+
+		log_err("Cannot boot EFI app on media '%s'\n",
+			dev_get_uclass_name(media_dev));
+
+		return NULL;
+	}
+
+	if (device_get_uclass_id(media_dev) == UCLASS_MASS_STORAGE)
+		return "usb";
+
+	return blk_get_uclass_name(device_get_uclass_id(media_dev));
+}
+
+efi_status_t efi_bootflow_run(struct bootflow *bflow)
+{
+	struct efi_device_path *device, *image;
+	const struct udevice *media_dev;
+	struct blk_desc *desc = NULL;
+	const char *dev_name;
+	char devnum_str[9];
+	efi_status_t ret;
+	void *fdt;
+
+	media_dev = dev_get_parent(bflow->dev);
+	if (bflow->blk) {
+		desc = dev_get_uclass_plat(bflow->blk);
+
+		snprintf(devnum_str, sizeof(devnum_str), "%x:%x",
+			 desc ? desc->devnum : dev_seq(media_dev), bflow->part);
+	} else {
+		*devnum_str = '\0';
+	}
+
+	dev_name = calc_dev_name(bflow);
+	log_debug("dev_name '%s' devnum_str '%s' fname '%s' media_dev '%s'\n",
+		  dev_name, devnum_str, bflow->fname, media_dev->name);
+	if (!dev_name)
+		return EFI_UNSUPPORTED;
+	ret = calculate_paths(dev_name, devnum_str, bflow->fname, &device,
+			      &image);
+	if (ret)
+		return EFI_UNSUPPORTED;
+
+	if (bflow->flags & BOOTFLOWF_USE_BUILTIN_FDT) {
+		log_debug("Booting with built-in fdt\n");
+		fdt = EFI_FDT_USE_INTERNAL;
+	} else {
+		log_debug("Booting with external fdt\n");
+		fdt = map_sysmem(bflow->fdt_addr, 0);
+	}
+	ret = _efi_binary_run(bflow->buf, bflow->size, fdt, device, image);
+
+	return ret;
+}
+