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@@ -0,0 +1,98 @@
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+// SPDX-License-Identifier: GPL-2.0+
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+/*
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+ * Copyright (c) 2020, Linaro Limited
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+ */
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+
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+#define LOG_CATEGORY LOGC_EFI
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+#include <common.h>
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+#include <env.h>
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+#include <malloc.h>
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+#include <dm.h>
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+#include <fs.h>
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+#include <efi_load_initrd.h>
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+#include <efi_loader.h>
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+#include <efi_variable.h>
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+
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+/**
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+ * efi_create_current_boot_var() - Return Boot#### name were #### is replaced by
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+ * the value of BootCurrent
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+ *
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+ * @var_name: variable name
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+ * @var_name_size: size of var_name
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+ *
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+ * Return: Status code
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+ */
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+static efi_status_t efi_create_current_boot_var(u16 var_name[],
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+ size_t var_name_size)
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+{
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+ efi_uintn_t boot_current_size;
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+ efi_status_t ret;
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+ u16 boot_current;
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+ u16 *pos;
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+
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+ boot_current_size = sizeof(boot_current);
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+ ret = efi_get_variable_int(L"BootCurrent",
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+ &efi_global_variable_guid, NULL,
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+ &boot_current_size, &boot_current, NULL);
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+ if (ret != EFI_SUCCESS)
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+ goto out;
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+
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+ pos = efi_create_indexed_name(var_name, var_name_size, "Boot",
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+ boot_current);
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+ if (!pos) {
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+ ret = EFI_OUT_OF_RESOURCES;
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+ goto out;
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+ }
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+
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+out:
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+ return ret;
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+}
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+
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+/**
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+ * efi_get_dp_from_boot() - Retrieve and return a device path from an EFI
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+ * Boot### variable.
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+ * A boot option may contain an array of device paths.
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+ * We use a VenMedia() with a specific GUID to identify
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+ * the usage of the array members. This function is
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+ * used to extract a specific device path
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+ *
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+ * @guid: vendor GUID of the VenMedia() device path node identifying the
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+ * device path
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+ *
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+ * Return: device path or NULL. Caller must free the returned value
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+ */
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+struct efi_device_path *efi_get_dp_from_boot(const efi_guid_t guid)
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+{
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+ struct efi_device_path *file_path = NULL;
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+ struct efi_device_path *tmp = NULL;
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+ struct efi_load_option lo;
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+ void *var_value = NULL;
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+ efi_uintn_t size;
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+ efi_status_t ret;
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+ u16 var_name[16];
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+
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+ ret = efi_create_current_boot_var(var_name, sizeof(var_name));
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+ if (ret != EFI_SUCCESS)
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+ return NULL;
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+
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+ var_value = efi_get_var(var_name, &efi_global_variable_guid, &size);
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+ if (!var_value)
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+ return NULL;
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+
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+ ret = efi_deserialize_load_option(&lo, var_value, &size);
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+ if (ret != EFI_SUCCESS)
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+ goto out;
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+
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+ tmp = efi_dp_from_lo(&lo, &size, guid);
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+ if (!tmp)
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+ goto out;
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+
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+ /* efi_dp_dup will just return NULL if efi_dp_next is NULL */
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+ file_path = efi_dp_dup(efi_dp_next(tmp));
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+
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+out:
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+ efi_free_pool(tmp);
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+ free(var_value);
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+
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+ return file_path;
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+}
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