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diff --git a/include/export/lib/bl_aux_params/bl_aux_params_exp.h b/include/export/lib/bl_aux_params/bl_aux_params_exp.h
new file mode 100644
index 0000000..7391dec
--- /dev/null
+++ b/include/export/lib/bl_aux_params/bl_aux_params_exp.h
@@ -0,0 +1,89 @@
+/*
+ * Copyright (c) 2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef ARM_TRUSTED_FIRMWARE_EXPORT_LIB_BL_AUX_PARAMS_EXP_H
+#define ARM_TRUSTED_FIRMWARE_EXPORT_LIB_BL_AUX_PARAMS_EXP_H
+
+/* EXPORT HEADER -- See include/export/README for details! -- EXPORT HEADER */
+
+#include "../../drivers/gpio_exp.h"
+
+/*
+ * This API implements a lightweight parameter passing mechanism that can be
+ * used to pass SoC Firmware configuration data from BL2 to BL31 by platforms or
+ * configurations that do not want to depend on libfdt. It is structured as a
+ * singly-linked list of parameter structures that all share the same common
+ * header but may have different (and differently-sized) structure bodies after
+ * that. The header contains a type field to indicate the parameter type (which
+ * is used to infer the structure length and how to interpret its contents) and
+ * a next pointer which contains the absolute physical address of the next
+ * parameter structure. The next pointer in the last structure block is set to
+ * NULL. The picture below shows how the parameters are kept in memory.
+ *
+ * head of list  ---> +----------------+ --+
+ *                    |      type      |   |
+ *                    +----------------+   |--> struct bl_aux_param
+ *               +----|      next      |   |
+ *               |    +----------------+ --+
+ *               |    | parameter data |
+ *               |    +----------------+
+ *               |
+ *               +--> +----------------+ --+
+ *                    |      type      |   |
+ *                    +----------------+   |--> struct bl_aux_param
+ *           NULL <---|      next      |   |
+ *                    +----------------+ --+
+ *                    | parameter data |
+ *                    +----------------+
+ *
+ * Note: The SCTLR_EL3.A bit (Alignment fault check enable) is set in TF-A, so
+ * BL2 must ensure that each parameter struct starts on a 64-bit aligned address
+ * to avoid alignment faults. Parameters may be allocated in any address range
+ * accessible at the time of BL31 handoff (e.g. SRAM, DRAM, SoC-internal scratch
+ * registers, etc.), in particular address ranges that may not be mapped in
+ * BL31's page tables, so the parameter list must be parsed before the MMU is
+ * enabled and any information that is required at a later point should be
+ * deep-copied out into BL31-internal data structures.
+ */
+
+enum bl_aux_param_type {
+	BL_AUX_PARAM_NONE = 0,
+	BL_AUX_PARAM_VENDOR_SPECIFIC_FIRST = 0x1,
+	/* 0x1 - 0x7fffffff can be used by vendor-specific handlers. */
+	BL_AUX_PARAM_VENDOR_SPECIFIC_LAST = 0x7fffffff,
+	BL_AUX_PARAM_GENERIC_FIRST = 0x80000001,
+	BL_AUX_PARAM_COREBOOT_TABLE = BL_AUX_PARAM_GENERIC_FIRST,
+	/* 0x80000001 - 0xffffffff are reserved for the generic handler. */
+	BL_AUX_PARAM_GENERIC_LAST = 0xffffffff,
+	/* Top 32 bits of the type field are reserved for future use. */
+};
+
+/* common header for all BL aux parameters */
+struct bl_aux_param_header {
+	uint64_t type;
+	uint64_t next;
+};
+
+/* commonly useful parameter structures that can be shared by multiple types */
+struct bl_aux_param_uint64 {
+	struct bl_aux_param_header h;
+	uint64_t value;
+};
+
+struct bl_aux_gpio_info {
+	uint8_t polarity;
+	uint8_t direction;
+	uint8_t pull_mode;
+	uint8_t reserved;
+	uint32_t index;
+};
+
+struct bl_aux_param_gpio {
+	struct bl_aux_param_header h;
+	struct bl_aux_gpio_info gpio;
+};
+
+#endif /* ARM_TRUSTED_FIRMWARE_EXPORT_LIB_BL_AUX_PARAMS_EXP_H */