Add submodule dependency filesHEADmaster

Change-Id: Iaf8d18082d3991dec7c0ebbea540f092188eb4ec

1 files changed, 236 insertions, 0 deletions

diff --git a/roms/u-boot/lib/efi_loader/efi_load_initrd.c b/roms/u-boot/lib/efi_loader/efi_load_initrd.c
new file mode 100644
index 000000000..e2a806302
--- /dev/null
+++ b/roms/u-boot/lib/efi_loader/efi_load_initrd.c
@@ -0,0 +1,236 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2020, Linaro Limited
+ */
+
+#define LOG_CATEGORY LOGC_EFI
+#include <common.h>
+#include <efi_loader.h>
+#include <efi_load_initrd.h>
+#include <efi_variable.h>
+#include <fs.h>
+#include <malloc.h>
+#include <mapmem.h>
+
+static efi_status_t EFIAPI
+efi_load_file2_initrd(struct efi_load_file_protocol *this,
+		      struct efi_device_path *file_path, bool boot_policy,
+		      efi_uintn_t *buffer_size, void *buffer);
+
+static const struct efi_load_file_protocol efi_lf2_protocol = {
+	.load_file = efi_load_file2_initrd,
+};
+
+/*
+ * Device path defined by Linux to identify the handle providing the
+ * EFI_LOAD_FILE2_PROTOCOL used for loading the initial ramdisk.
+ */
+static const struct efi_initrd_dp dp_lf2_handle = {
+	.vendor = {
+		{
+		   DEVICE_PATH_TYPE_MEDIA_DEVICE,
+		   DEVICE_PATH_SUB_TYPE_VENDOR_PATH,
+		   sizeof(dp_lf2_handle.vendor),
+		},
+		EFI_INITRD_MEDIA_GUID,
+	},
+	.end = {
+		DEVICE_PATH_TYPE_END,
+		DEVICE_PATH_SUB_TYPE_END,
+		sizeof(dp_lf2_handle.end),
+	}
+};
+
+static efi_handle_t efi_initrd_handle;
+
+/**
+ * get_initrd_fp() - Get initrd device path from a FilePathList device path
+ *
+ * @initrd_fp:	the final initrd filepath
+ *
+ * Return:	status code. Caller must free initrd_fp
+ */
+static efi_status_t get_initrd_fp(struct efi_device_path **initrd_fp)
+{
+	const efi_guid_t lf2_initrd_guid = EFI_INITRD_MEDIA_GUID;
+	struct efi_device_path *dp = NULL;
+
+	/*
+	 * if bootmgr is setup with and initrd, the device path will be
+	 * in the FilePathList[] of our load options in Boot####.
+	 * The first device path of the multi instance device path will
+	 * start with a VenMedia and the initrds will follow.
+	 *
+	 * If the device path is not found return EFI_INVALID_PARAMETER.
+	 * We can then use this specific return value and not install the
+	 * protocol, while allowing the boot to continue
+	 */
+	dp = efi_get_dp_from_boot(lf2_initrd_guid);
+	if (!dp)
+		return EFI_INVALID_PARAMETER;
+
+	*initrd_fp = dp;
+	return EFI_SUCCESS;
+}
+
+/**
+ * efi_load_file2_initrd() - load initial RAM disk
+ *
+ * This function implements the LoadFile service of the EFI_LOAD_FILE2_PROTOCOL
+ * in order to load an initial RAM disk requested by the Linux kernel stub.
+ *
+ * See the UEFI spec for details.
+ *
+ * @this:			EFI_LOAD_FILE2_PROTOCOL instance
+ * @file_path:			media device path of the file, "" in this case
+ * @boot_policy:		must be false
+ * @buffer_size:		size of allocated buffer
+ * @buffer:			buffer to load the file
+ *
+ * Return:			status code
+ */
+static efi_status_t EFIAPI
+efi_load_file2_initrd(struct efi_load_file_protocol *this,
+		      struct efi_device_path *file_path, bool boot_policy,
+		      efi_uintn_t *buffer_size, void *buffer)
+{
+	struct efi_device_path *initrd_fp = NULL;
+	efi_status_t ret = EFI_NOT_FOUND;
+	struct efi_file_handle *f = NULL;
+	efi_uintn_t bs;
+
+	EFI_ENTRY("%p, %p, %d, %p, %p", this, file_path, boot_policy,
+		  buffer_size, buffer);
+
+	if (!this || this != &efi_lf2_protocol ||
+	    !buffer_size) {
+		ret = EFI_INVALID_PARAMETER;
+		goto out;
+	}
+
+	if (file_path->type != dp_lf2_handle.end.type ||
+	    file_path->sub_type != dp_lf2_handle.end.sub_type) {
+		ret = EFI_INVALID_PARAMETER;
+		goto out;
+	}
+
+	if (boot_policy) {
+		ret = EFI_UNSUPPORTED;
+		goto out;
+	}
+
+	ret = get_initrd_fp(&initrd_fp);
+	if (ret != EFI_SUCCESS)
+		goto out;
+
+	/* Open file */
+	f = efi_file_from_path(initrd_fp);
+	if (!f) {
+		log_err("Can't find initrd specified in Boot####\n");
+		ret = EFI_NOT_FOUND;
+		goto out;
+	}
+
+	/* Get file size */
+	ret = efi_file_size(f, &bs);
+	if (ret != EFI_SUCCESS)
+		goto out;
+
+	if (!buffer || *buffer_size < bs) {
+		ret = EFI_BUFFER_TOO_SMALL;
+		*buffer_size = bs;
+	} else {
+		ret = EFI_CALL(f->read(f, &bs, (void *)(uintptr_t)buffer));
+		*buffer_size = bs;
+	}
+
+out:
+	efi_free_pool(initrd_fp);
+	if (f)
+		EFI_CALL(f->close(f));
+	return EFI_EXIT(ret);
+}
+
+/**
+ * check_initrd() - Determine if the file defined as an initrd in Boot####
+ *		    load_options device path is present
+ *
+ * Return:	status code
+ */
+static efi_status_t check_initrd(void)
+{
+	struct efi_device_path *initrd_fp = NULL;
+	struct efi_file_handle *f;
+	efi_status_t ret;
+
+	ret = get_initrd_fp(&initrd_fp);
+	if (ret != EFI_SUCCESS)
+		goto out;
+
+	/*
+	 * If the file is not found, but the file path is set, return an error
+	 * and trigger the bootmgr fallback
+	 */
+	f = efi_file_from_path(initrd_fp);
+	if (!f) {
+		log_err("Can't find initrd specified in Boot####\n");
+		ret = EFI_NOT_FOUND;
+		goto out;
+	}
+
+	EFI_CALL(f->close(f));
+
+out:
+	efi_free_pool(initrd_fp);
+	return ret;
+}
+
+/**
+ * efi_initrd_register() - create handle for loading initial RAM disk
+ *
+ * This function creates a new handle and installs a Linux specific vendor
+ * device path and an EFI_LOAD_FILE2_PROTOCOL. Linux uses the device path
+ * to identify the handle and then calls the LoadFile service of the
+ * EFI_LOAD_FILE2_PROTOCOL to read the initial RAM disk.
+ *
+ * Return:	status code
+ */
+efi_status_t efi_initrd_register(void)
+{
+	efi_status_t ret;
+
+	/*
+	 * Allow the user to continue if Boot#### file path is not set for
+	 * an initrd
+	 */
+	ret = check_initrd();
+	if (ret == EFI_INVALID_PARAMETER)
+		return EFI_SUCCESS;
+	if (ret != EFI_SUCCESS)
+		return ret;
+
+	ret = EFI_CALL(efi_install_multiple_protocol_interfaces
+		       (&efi_initrd_handle,
+			/* initramfs */
+			&efi_guid_device_path, &dp_lf2_handle,
+			/* LOAD_FILE2 */
+			&efi_guid_load_file2_protocol,
+			(void *)&efi_lf2_protocol,
+			NULL));
+
+	return ret;
+}
+
+/**
+ * efi_initrd_deregister() - delete the handle for loading initial RAM disk
+ *
+ * This will delete the handle containing the Linux specific vendor device
+ * path and EFI_LOAD_FILE2_PROTOCOL for loading an initrd
+ *
+ * Return:	status code
+ */
+void efi_initrd_deregister(void)
+{
+	efi_delete_handle(efi_initrd_handle);
+	efi_initrd_handle = NULL;
+}