feat(tsp): add ffa_helpers to enable more FF-A functionality

Include ffa_helpers originally taken from the TF-A Tests repo
to provide support for additional FF-A functionality.

Change-Id: Iacc3ee270d5e3903f86f8078ed915d1e791c1298
Signed-off-by: Marc Bonnici <marc.bonnici@arm.com>
Signed-off-by: Shruti Gupta <shruti.gupta@arm.com>

3 files changed, 234 insertions, 1 deletions

diff --git a/bl32/tsp/ffa_helpers.c b/bl32/tsp/ffa_helpers.c
new file mode 100644
index 000000000..296957eb1
--- /dev/null
+++ b/bl32/tsp/ffa_helpers.c
@@ -0,0 +1,125 @@
+/*
+ * Copyright (c) 2022, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <common/debug.h>
+#include "ffa_helpers.h"
+#include <services/ffa_svc.h>
+#include "tsp_private.h"
+
+/**
+ * Initialises the header of the given `ffa_mtd`, not including the
+ * composite memory region offset.
+ */
+static void ffa_memory_region_init_header(
+	struct ffa_mtd *memory_region, ffa_endpoint_id16_t sender,
+	ffa_mem_attr16_t attributes, ffa_mtd_flag32_t flags,
+	uint64_t handle, uint64_t tag, ffa_endpoint_id16_t *receivers,
+	uint32_t receiver_count, ffa_mem_perm8_t permissions)
+{
+	struct ffa_emad_v1_0 *emad;
+
+	memory_region->emad_offset = sizeof(struct ffa_mtd);
+	memory_region->emad_size = sizeof(struct ffa_emad_v1_0);
+	emad = (struct ffa_emad_v1_0 *)
+		    ((uint8_t *) memory_region +
+		     memory_region->emad_offset);
+	memory_region->sender_id = sender;
+	memory_region->memory_region_attributes = attributes;
+	memory_region->reserved_36_39 = 0;
+	memory_region->flags = flags;
+	memory_region->handle = handle;
+	memory_region->tag = tag;
+	memory_region->reserved_40_47 = 0;
+	memory_region->emad_count = receiver_count;
+	for (uint32_t i = 0U; i < receiver_count; i++) {
+		emad[i].mapd.endpoint_id = receivers[i];
+		emad[i].mapd.memory_access_permissions = permissions;
+		emad[i].mapd.flags = 0;
+		emad[i].comp_mrd_offset = 0;
+		emad[i].reserved_8_15 = 0;
+	}
+}
+/**
+ * Initialises the given `ffa_mtd` to be used for an
+ * `FFA_MEM_RETRIEVE_REQ` by the receiver of a memory transaction.
+ * TODO: Support differing attributes per receiver.
+ *
+ * Returns the size of the descriptor written.
+ */
+uint32_t ffa_memory_retrieve_request_init(
+	struct ffa_mtd *memory_region, uint64_t handle,
+	ffa_endpoint_id16_t sender, ffa_endpoint_id16_t *receivers, uint32_t receiver_count,
+	uint64_t tag, ffa_mtd_flag32_t flags,
+	ffa_mem_perm8_t permissions,
+	ffa_mem_attr16_t attributes)
+{
+	ffa_memory_region_init_header(memory_region, sender, attributes, flags,
+				      handle, tag, receivers,
+				      receiver_count, permissions);
+
+	return sizeof(struct ffa_mtd) +
+	       memory_region->emad_count * sizeof(struct ffa_emad_v1_0);
+}
+
+/* Relinquish access to memory region. */
+bool ffa_mem_relinquish(void)
+{
+	smc_args_t ret;
+
+	ret = smc_helper(FFA_MEM_RELINQUISH, 0, 0, 0, 0, 0, 0, 0);
+	if (ffa_func_id(ret) != FFA_SUCCESS_SMC32) {
+		ERROR("%s failed to relinquish memory! error: (%x) %x\n",
+		      __func__, ffa_func_id(ret), ffa_error_code(ret));
+		return false;
+	}
+	return true;
+}
+
+/* Retrieve memory shared by another partition. */
+smc_args_t ffa_mem_retrieve_req(uint32_t descriptor_length,
+				uint32_t fragment_length)
+{
+	return smc_helper(FFA_MEM_RETRIEVE_REQ_SMC32,
+		      descriptor_length,
+		      fragment_length,
+		      0, 0, 0, 0, 0);
+}
+
+/* Retrieve the next memory descriptor fragment. */
+smc_args_t ffa_mem_frag_rx(uint64_t handle, uint32_t recv_length)
+{
+	return smc_helper(FFA_MEM_FRAG_RX,
+		       FFA_MEM_HANDLE_LOW(handle),
+		       FFA_MEM_HANDLE_HIGH(handle),
+		       recv_length,
+		       0, 0, 0, 0);
+}
+
+/* Relinquish the memory region. */
+bool memory_relinquish(struct ffa_mem_relinquish_descriptor *m, uint64_t handle,
+		       ffa_endpoint_id16_t id)
+{
+	ffa_mem_relinquish_init(m, handle, 0, id);
+	return ffa_mem_relinquish();
+}
+
+/* Query SPMC that the rx buffer of the partition can be released. */
+bool ffa_rx_release(void)
+{
+	smc_args_t ret;
+
+	ret = smc_helper(FFA_RX_RELEASE, 0, 0, 0, 0, 0, 0, 0);
+	return ret._regs[SMC_ARG0] != FFA_SUCCESS_SMC32;
+}
+
+/* Map the provided buffers with the SPMC. */
+bool ffa_rxtx_map(uintptr_t send, uintptr_t recv, uint32_t pages)
+{
+	smc_args_t ret;
+
+	ret = smc_helper(FFA_RXTX_MAP_SMC64, send, recv, pages, 0, 0, 0, 0);
+	return ret._regs[0] != FFA_SUCCESS_SMC32;
+}
diff --git a/bl32/tsp/ffa_helpers.h b/bl32/tsp/ffa_helpers.h
new file mode 100644
index 000000000..e8bd51d00
--- /dev/null
+++ b/bl32/tsp/ffa_helpers.h
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 2022, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef FFA_HELPERS_H
+#define FFA_HELPERS_H
+
+#include <stdint.h>
+
+#include "../../services/std_svc/spm/el3_spmc/spmc.h"
+#include "../../services/std_svc/spm/el3_spmc/spmc_shared_mem.h"
+#include <services/el3_spmc_ffa_memory.h>
+#include <services/ffa_svc.h>
+#include "tsp_private.h"
+
+static inline uint32_t ffa_func_id(smc_args_t val)
+{
+	return (uint32_t) val._regs[0];
+}
+
+static inline int32_t ffa_error_code(smc_args_t val)
+{
+	return (uint32_t) val._regs[2];
+}
+
+/** The maximum number of recipients a memory region may be sent to. */
+#define MAX_MEM_SHARE_RECIPIENTS	2U
+
+/* FFA Memory Management mode flags. */
+#define FFA_FLAG_SHARE_MEMORY (1U << 3)
+#define FFA_FLAG_LEND_MEMORY (1U << 4)
+
+#define FFA_FLAG_MEMORY_MASK (3U << 3)
+
+#define FFA_MEM_HANDLE_LOW(x) (x & 0xFFFFFFFF)
+#define FFA_MEM_HANDLE_HIGH(x) (x >> 32)
+
+#define FFA_MEM_PERM_DATA_OFFSET 0
+#define FFA_MEM_PERM_DATA_MASK 0x3
+
+static inline uint32_t ffa_mem_relinquish_init(
+	struct ffa_mem_relinquish_descriptor *relinquish_request,
+	uint64_t handle, ffa_mtd_flag32_t flags,
+	ffa_endpoint_id16_t sender)
+{
+	relinquish_request->handle = handle;
+	relinquish_request->flags = flags;
+	relinquish_request->endpoint_count = 1;
+	relinquish_request->endpoint_array[0] = sender;
+
+	return sizeof(struct ffa_mem_relinquish_descriptor) + sizeof(ffa_endpoint_id16_t);
+}
+
+/**
+ * Gets the `ffa_comp_mrd` for the given receiver from an
+ * `ffa_mtd`, or NULL if it is not valid.
+ */
+static inline struct ffa_comp_mrd *
+ffa_memory_region_get_composite(struct ffa_mtd *memory_region,
+				uint32_t receiver_index)
+{
+	struct ffa_emad_v1_0 *receivers;
+	uint32_t offset;
+
+	receivers = (struct ffa_emad_v1_0 *)
+		    ((uint8_t *) memory_region +
+		    memory_region->emad_offset +
+		    (memory_region->emad_size * receiver_index));
+	offset = receivers->comp_mrd_offset;
+
+	if (offset == 0U) {
+		return NULL;
+	}
+
+	return (struct ffa_comp_mrd *)
+	       ((uint8_t *) memory_region + offset);
+}
+
+static inline uint32_t ffa_get_data_access_attr(ffa_mem_perm8_t perm)
+{
+	return ((perm >> FFA_MEM_PERM_DATA_OFFSET) & FFA_MEM_PERM_DATA_MASK);
+}
+
+/**
+ * Initialises the given `ffa_mtd` to be used for an
+ * `FFA_MEM_RETRIEVE_REQ` by the receiver of a memory transaction.
+ *
+ * Returns the size of the message written.
+ */
+uint32_t ffa_memory_retrieve_request_init(
+	struct ffa_mtd *memory_region, uint64_t handle,
+	ffa_endpoint_id16_t sender, ffa_endpoint_id16_t *test_receivers, uint32_t receiver_count,
+	uint64_t tag, ffa_mtd_flag32_t flags,
+	ffa_mem_perm8_t permissions, ffa_mem_attr16_t attributes);
+
+smc_args_t ffa_mem_frag_rx(uint64_t handle, uint32_t recv_length);
+smc_args_t ffa_mem_retrieve_req(uint32_t descriptor_length,
+				uint32_t fragment_length);
+bool ffa_mem_relinquish(void);
+bool ffa_rx_release(void);
+bool memory_relinquish(struct ffa_mem_relinquish_descriptor *m, uint64_t handle,
+		       ffa_endpoint_id16_t id);
+bool ffa_rxtx_map(uintptr_t send, uintptr_t recv, uint32_t pages);
+
+#endif /* FFA_HELPERS_H */
diff --git a/bl32/tsp/tsp.mk b/bl32/tsp/tsp.mk
index 3dfa80216..c31b9b543 100644
--- a/bl32/tsp/tsp.mk
+++ b/bl32/tsp/tsp.mk
@@ -7,7 +7,8 @@
 INCLUDES		+=	-Iinclude/bl32/tsp
 
 ifeq (${SPMC_AT_EL3},1)
-   BL32_SOURCES            +=      bl32/tsp/tsp_ffa_main.c
+   BL32_SOURCES            +=      bl32/tsp/tsp_ffa_main.c                    \
+				   bl32/tsp/ffa_helpers.c
 else
    BL32_SOURCES            +=      bl32/tsp/tsp_main.c
 endif