1 /* 2 * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved. 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 */ 6 7 #include <arch_helpers.h> 8 #include <assert.h> 9 #include <bl_common.h> 10 #include <context_mgmt.h> 11 #include <string.h> 12 #include "tlkd_private.h" 13 14 #define AT_MASK 3 15 16 /******************************************************************************* 17 * This function helps the SP to translate NS/S virtual addresses. 18 ******************************************************************************/ 19 uint64_t tlkd_va_translate(uintptr_t va, int type) 20 { 21 uint64_t pa; 22 23 if (type & TLK_TRANSLATE_NS_VADDR) { 24 25 /* save secure context */ 26 cm_el1_sysregs_context_save(SECURE); 27 28 /* restore non-secure context */ 29 cm_el1_sysregs_context_restore(NON_SECURE); 30 31 /* switch NS bit to start using 64-bit, non-secure mappings */ 32 write_scr(cm_get_scr_el3(NON_SECURE)); 33 isb(); 34 } 35 36 int at = type & AT_MASK; 37 switch (at) { 38 case 0: 39 ats12e1r(va); 40 break; 41 case 1: 42 ats12e1w(va); 43 break; 44 case 2: 45 ats12e0r(va); 46 break; 47 case 3: 48 ats12e0w(va); 49 break; 50 default: 51 assert(0); /* Unreachable */ 52 break; 53 } 54 55 /* get the (NS/S) physical address */ 56 isb(); 57 pa = read_par_el1(); 58 59 /* Restore secure state */ 60 if (type & TLK_TRANSLATE_NS_VADDR) { 61 62 /* restore secure context */ 63 cm_el1_sysregs_context_restore(SECURE); 64 65 /* switch NS bit to start using 32-bit, secure mappings */ 66 write_scr(cm_get_scr_el3(SECURE)); 67 isb(); 68 } 69 70 return pa; 71 } 72 73 /******************************************************************************* 74 * Given a secure payload entrypoint, register width, cpu id & pointer to a 75 * context data structure, this function will create a secure context ready for 76 * programming an entry into the secure payload. 77 ******************************************************************************/ 78 void tlkd_init_tlk_ep_state(struct entry_point_info *tlk_entry_point, 79 uint32_t rw, 80 uint64_t pc, 81 tlk_context_t *tlk_ctx) 82 { 83 uint32_t ep_attr, spsr; 84 85 /* Passing a NULL context is a critical programming error */ 86 assert(tlk_ctx); 87 assert(tlk_entry_point); 88 assert(pc); 89 90 /* Associate this context with the cpu specified */ 91 tlk_ctx->mpidr = read_mpidr_el1(); 92 clr_yield_smc_active_flag(tlk_ctx->state); 93 cm_set_context(&tlk_ctx->cpu_ctx, SECURE); 94 95 if (rw == SP_AARCH64) 96 spsr = SPSR_64(MODE_EL1, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS); 97 else 98 spsr = SPSR_MODE32(MODE32_svc, 99 SPSR_T_ARM, 100 read_sctlr_el3() & SCTLR_EE_BIT, 101 DISABLE_ALL_EXCEPTIONS); 102 103 /* initialise an entrypoint to set up the CPU context */ 104 ep_attr = SECURE | EP_ST_ENABLE; 105 if (read_sctlr_el3() & SCTLR_EE_BIT) 106 ep_attr |= EP_EE_BIG; 107 SET_PARAM_HEAD(tlk_entry_point, PARAM_EP, VERSION_1, ep_attr); 108 109 tlk_entry_point->pc = pc; 110 tlk_entry_point->spsr = spsr; 111 } 112 113 /******************************************************************************* 114 * This function takes a TLK context pointer and: 115 * 1. Applies the S-EL1 system register context from tlk_ctx->cpu_ctx. 116 * 2. Saves the current C runtime state (callee saved registers) on the stack 117 * frame and saves a reference to this state. 118 * 3. Calls el3_exit() so that the EL3 system and general purpose registers 119 * from the tlk_ctx->cpu_ctx are used to enter the secure payload image. 120 ******************************************************************************/ 121 uint64_t tlkd_synchronous_sp_entry(tlk_context_t *tlk_ctx) 122 { 123 uint64_t rc; 124 125 /* Passing a NULL context is a critical programming error */ 126 assert(tlk_ctx); 127 assert(tlk_ctx->c_rt_ctx == 0); 128 129 /* Apply the Secure EL1 system register context and switch to it */ 130 assert(cm_get_context(SECURE) == &tlk_ctx->cpu_ctx); 131 cm_el1_sysregs_context_restore(SECURE); 132 cm_set_next_eret_context(SECURE); 133 134 rc = tlkd_enter_sp(&tlk_ctx->c_rt_ctx); 135 #if ENABLE_ASSERTIONS 136 tlk_ctx->c_rt_ctx = 0; 137 #endif 138 139 return rc; 140 } 141 142 /******************************************************************************* 143 * This function takes a TLK context pointer and: 144 * 1. Saves the S-EL1 system register context to tlk_ctx->cpu_ctx. 145 * 2. Restores the current C runtime state (callee saved registers) from the 146 * stack frame using reference to this state saved in tlkd_enter_sp(). 147 * 3. It does not need to save any general purpose or EL3 system register state 148 * as the generic smc entry routine should have saved those. 149 ******************************************************************************/ 150 void tlkd_synchronous_sp_exit(tlk_context_t *tlk_ctx, uint64_t ret) 151 { 152 /* Passing a NULL context is a critical programming error */ 153 assert(tlk_ctx); 154 155 /* Save the Secure EL1 system register context */ 156 assert(cm_get_context(SECURE) == &tlk_ctx->cpu_ctx); 157 cm_el1_sysregs_context_save(SECURE); 158 159 assert(tlk_ctx->c_rt_ctx != 0); 160 tlkd_exit_sp(tlk_ctx->c_rt_ctx, ret); 161 162 /* Should never reach here */ 163 assert(0); 164 } 165