Diff: mbed-dev-master/cmsis/TARGET_CORTEX_M/mbed_tz_context.c

Revision:

0:bb348c97df44

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed-dev-master/cmsis/TARGET_CORTEX_M/mbed_tz_context.c	Wed Sep 16 01:11:49 2020 +0000
@@ -0,0 +1,212 @@
+/******************************************************************************
+ * @file     tz_context.c
+ * @brief    Context Management for Armv8-M TrustZone - Sample implementation
+ * @version  V1.1.1
+ * @date     10. January 2018
+ ******************************************************************************/
+/*
+ * Copyright (c) 2016-2018 Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the License); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an AS IS BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * ----------------------------------------------------------------------------
+ *
+ * $Date:        15. October 2016
+ * $Revision:    1.1.0
+ *
+ * Project:      TrustZone for ARMv8-M
+ * Title:        Context Management for ARMv8-M TrustZone - Sample implementation
+ *
+ *---------------------------------------------------------------------------*/
+ 
+#if defined (__ARM_FEATURE_CMSE) &&  (__ARM_FEATURE_CMSE == 3U)
+
+#include "RTE_Components.h"
+#include CMSIS_device_header
+#include "tz_context.h"
+
+/// Number of process slots (threads may call secure library code)
+#ifndef TZ_PROCESS_STACK_SLOTS
+#define TZ_PROCESS_STACK_SLOTS     8U
+#endif
+
+/// Stack size of the secure library code
+#ifndef TZ_PROCESS_STACK_SIZE
+#define TZ_PROCESS_STACK_SIZE      256U
+#endif
+
+typedef struct {
+  uint32_t sp_top;      // stack space top
+  uint32_t sp_limit;    // stack space limit
+  uint32_t sp;          // current stack pointer
+} stack_info_t;
+
+static stack_info_t ProcessStackInfo  [TZ_PROCESS_STACK_SLOTS];
+static uint64_t     ProcessStackMemory[TZ_PROCESS_STACK_SLOTS][TZ_PROCESS_STACK_SIZE/8U];
+static uint32_t     ProcessStackFreeSlot = 0xFFFFFFFFU;
+
+
+/// Initialize secure context memory system
+/// \return execution status (1: success, 0: error)
+__attribute__((cmse_nonsecure_entry))
+uint32_t TZ_InitContextSystem_S (void) {
+  uint32_t n;
+
+  if (__get_IPSR() == 0U) {
+    return 0U;  // Thread Mode
+  }
+
+  for (n = 0U; n < TZ_PROCESS_STACK_SLOTS; n++) {
+    ProcessStackInfo[n].sp = 0U;
+    ProcessStackInfo[n].sp_limit = (uint32_t)&ProcessStackMemory[n];
+    ProcessStackInfo[n].sp_top   = (uint32_t)&ProcessStackMemory[n] + TZ_PROCESS_STACK_SIZE;
+    *((uint32_t *)ProcessStackMemory[n]) = n + 1U;
+  }
+  *((uint32_t *)ProcessStackMemory[--n]) = 0xFFFFFFFFU;
+
+  ProcessStackFreeSlot = 0U;
+
+  // Default process stack pointer and stack limit
+  __set_PSPLIM((uint32_t)ProcessStackMemory);
+  __set_PSP   ((uint32_t)ProcessStackMemory);
+
+  // Privileged Thread Mode using PSP
+  __set_CONTROL(0x02U);
+
+  return 1U;    // Success
+}
+
+
+/// Allocate context memory for calling secure software modules in TrustZone
+/// \param[in]  module   identifies software modules called from non-secure mode
+/// \return value != 0 id TrustZone memory slot identifier
+/// \return value 0    no memory available or internal error
+__attribute__((cmse_nonsecure_entry))
+TZ_MemoryId_t TZ_AllocModuleContext_S (TZ_ModuleId_t module) {
+  uint32_t slot;
+
+  (void)module; // Ignore (fixed Stack size)
+
+  if (__get_IPSR() == 0U) {
+    return 0U;  // Thread Mode
+  }
+
+  if (ProcessStackFreeSlot == 0xFFFFFFFFU) {
+    return 0U;  // No slot available
+  }
+
+  slot = ProcessStackFreeSlot;
+  ProcessStackFreeSlot = *((uint32_t *)ProcessStackMemory[slot]);
+
+  ProcessStackInfo[slot].sp = ProcessStackInfo[slot].sp_top;
+
+  return (slot + 1U);
+}
+
+
+/// Free context memory that was previously allocated with \ref TZ_AllocModuleContext_S
+/// \param[in]  id  TrustZone memory slot identifier
+/// \return execution status (1: success, 0: error)
+__attribute__((cmse_nonsecure_entry))
+uint32_t TZ_FreeModuleContext_S (TZ_MemoryId_t id) {
+  uint32_t slot;
+
+  if (__get_IPSR() == 0U) {
+    return 0U;  // Thread Mode
+  }
+
+  if ((id == 0U) || (id > TZ_PROCESS_STACK_SLOTS)) {
+    return 0U;  // Invalid ID
+  }
+
+  slot = id - 1U;
+
+  if (ProcessStackInfo[slot].sp == 0U) {
+    return 0U;  // Inactive slot
+  }
+  ProcessStackInfo[slot].sp = 0U;
+
+  *((uint32_t *)ProcessStackMemory[slot]) = ProcessStackFreeSlot;
+  ProcessStackFreeSlot = slot;
+
+  return 1U;    // Success
+}
+
+
+/// Load secure context (called on RTOS thread context switch)
+/// \param[in]  id  TrustZone memory slot identifier
+/// \return execution status (1: success, 0: error)
+__attribute__((cmse_nonsecure_entry))
+uint32_t TZ_LoadContext_S (TZ_MemoryId_t id) {
+  uint32_t slot;
+
+  if ((__get_IPSR() == 0U) || ((__get_CONTROL() & 2U) == 0U)) {
+    return 0U;  // Thread Mode or using Main Stack for threads
+  }
+
+  if ((id == 0U) || (id > TZ_PROCESS_STACK_SLOTS)) {
+    return 0U;  // Invalid ID
+  }
+
+  slot = id - 1U;
+
+  if (ProcessStackInfo[slot].sp == 0U) {
+    return 0U;  // Inactive slot
+  }
+
+  // Setup process stack pointer and stack limit
+  __set_PSPLIM(ProcessStackInfo[slot].sp_limit);
+  __set_PSP   (ProcessStackInfo[slot].sp);
+
+  return 1U;    // Success
+}
+
+
+/// Store secure context (called on RTOS thread context switch)
+/// \param[in]  id  TrustZone memory slot identifier
+/// \return execution status (1: success, 0: error)
+__attribute__((cmse_nonsecure_entry))
+uint32_t TZ_StoreContext_S (TZ_MemoryId_t id) {
+  uint32_t slot;
+  uint32_t sp;
+
+  if ((__get_IPSR() == 0U) || ((__get_CONTROL() & 2U) == 0U)) {
+    return 0U;  // Thread Mode or using Main Stack for threads
+  }
+
+  if ((id == 0U) || (id > TZ_PROCESS_STACK_SLOTS)) {
+    return 0U;  // Invalid ID
+  }
+
+  slot = id - 1U;
+
+  if (ProcessStackInfo[slot].sp == 0U) {
+    return 0U;  // Inactive slot
+  }
+
+  sp = __get_PSP();
+  if ((sp < ProcessStackInfo[slot].sp_limit) ||
+      (sp > ProcessStackInfo[slot].sp_top)) {
+    return 0U;  // SP out of range
+  }
+  ProcessStackInfo[slot].sp = sp;
+
+  // Default process stack pointer and stack limit
+  __set_PSPLIM((uint32_t)ProcessStackMemory);
+  __set_PSP   ((uint32_t)ProcessStackMemory);
+
+  return 1U;    // Success
+}
+#endif