1 /* 2 * Copyright (c) 2018-2022, Arm Limited. All rights reserved. 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 * 6 */ 7 8 #ifndef __TFM_PLAT_NV_COUNTERS_H__ 9 #define __TFM_PLAT_NV_COUNTERS_H__ 10 11 /** 12 * \file tfm_plat_nv_counters.h 13 * 14 * \note The interfaces defined in this file must be implemented for each 15 * SoC. 16 * \note The interface must be implemented in a fail-safe way that is 17 * resistant to asynchronous power failures or it can use hardware 18 * counters that have this capability, if supported by the platform. 19 * When a counter incrementation was interrupted it must be able to 20 * continue the incrementation process or recover the previous consistent 21 * status of the counters. If the counters have reached a stable status 22 * (every counter incrementation operation has finished), from that point 23 * their value cannot decrease due to any kind of power failure. 24 */ 25 26 #include <stdint.h> 27 #include "tfm_plat_defs.h" 28 29 #ifndef PLATFORM_NS_NV_COUNTERS 30 #define PLATFORM_NS_NV_COUNTERS 0 31 #endif 32 33 enum tfm_nv_counter_t { 34 PLAT_NV_COUNTER_PS_0 = 0, /* Used by PS service */ 35 PLAT_NV_COUNTER_PS_1, /* Used by PS service */ 36 PLAT_NV_COUNTER_PS_2, /* Used by PS service */ 37 38 PLAT_NV_COUNTER_BL2_0, /* Used by bootloader */ 39 PLAT_NV_COUNTER_BL2_1, /* Used by bootloader */ 40 PLAT_NV_COUNTER_BL2_2, /* Used by bootloader */ 41 PLAT_NV_COUNTER_BL2_3, /* Used by bootloader */ 42 43 PLAT_NV_COUNTER_BL1_0, /* Used by bootloader */ 44 45 /* NS counters must be contiguous */ 46 PLAT_NV_COUNTER_NS_0, /* Used by NS */ 47 PLAT_NV_COUNTER_NS_1, /* Used by NS */ 48 PLAT_NV_COUNTER_NS_2, /* Used by NS */ 49 50 PLAT_NV_COUNTER_MAX, 51 PLAT_NV_COUNTER_BOUNDARY = UINT32_MAX /* Fix tfm_nv_counter_t size 52 to 4 bytes */ 53 }; 54 55 #ifdef __cplusplus 56 extern "C" { 57 #endif 58 59 /** 60 * \brief Initialises all non-volatile (NV) counters. 61 * 62 * \return TFM_PLAT_ERR_SUCCESS if the initialization succeeds, otherwise 63 * TFM_PLAT_ERR_SYSTEM_ERR 64 */ 65 enum tfm_plat_err_t tfm_plat_init_nv_counter(void); 66 67 /** 68 * \brief Reads the given non-volatile (NV) counter. 69 * 70 * \param[in] counter_id NV counter ID. 71 * \param[in] size Size of the buffer to store NV counter value 72 * in bytes. 73 * \param[out] val Pointer to store the current NV counter value. 74 * 75 * \return TFM_PLAT_ERR_SUCCESS if the value is read correctly. Otherwise, 76 * it returns TFM_PLAT_ERR_SYSTEM_ERR. 77 */ 78 enum tfm_plat_err_t tfm_plat_read_nv_counter(enum tfm_nv_counter_t counter_id, 79 uint32_t size, uint8_t *val); 80 81 /** 82 * \brief Increments the given non-volatile (NV) counter. 83 * 84 * \param[in] counter_id NV counter ID. 85 * 86 * \return When the NV counter reaches its maximum value, the 87 * TFM_PLAT_ERR_MAX_VALUE error is returned to indicate the value 88 * cannot be incremented. Otherwise, it returns TFM_PLAT_ERR_SUCCESS. 89 */ 90 enum tfm_plat_err_t tfm_plat_increment_nv_counter( 91 enum tfm_nv_counter_t counter_id); 92 93 /** 94 * \brief Sets the given non-volatile (NV) counter to the specified value. 95 * 96 * \param[in] counter_id NV counter ID. 97 * \param[in] value New value of the NV counter. The maximum value that 98 * can be set depends on the constraints of the 99 * underlying implementation, but it always must be 100 * greater than or equal to the current NV counter value. 101 * 102 * \retval TFM_PLAT_ERR_SUCCESS The NV counter is set successfully 103 * \retval TFM_PLAT_ERR_INVALID_INPUT The new value is less than the current 104 * counter value 105 * \retval TFM_PLAT_ERR_MAX_VALUE The new value is greater than the 106 * maximum value of the NV counter 107 * \retval TFM_PLAT_ERR_UNSUPPORTED The function is not implemented for 108 * the given platform or the new value is 109 * not representable on the underlying 110 * counter implementation 111 * \retval TFM_PLAT_ERR_SYSTEM_ERR An unspecified error occurred 112 * (none of the other standard error codes 113 * are applicable) 114 */ 115 enum tfm_plat_err_t tfm_plat_set_nv_counter(enum tfm_nv_counter_t counter_id, 116 uint32_t value); 117 118 #ifdef __cplusplus 119 } 120 #endif 121 122 #endif /* __TFM_PLAT_NV_COUNTERS_H__ */ 123
