1 /* 2 * Copyright (c) 2011 - 2019, Max Filippov, Open Source and Linux Lab. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * * Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * * Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * * Neither the name of the Open Source and Linux Lab nor the 13 * names of its contributors may be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 20 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 21 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 23 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 25 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #include "qemu/osdep.h" 29 #include "qemu/log.h" 30 #include "cpu.h" 31 #include "exec/helper-proto.h" 32 #include "qemu/host-utils.h" 33 34 static void copy_window_from_phys(CPUXtensaState *env, 35 uint32_t window, uint32_t phys, uint32_t n) 36 { 37 assert(phys < env->config->nareg); 38 if (phys + n <= env->config->nareg) { 39 memcpy(env->regs + window, env->phys_regs + phys, 40 n * sizeof(uint32_t)); 41 } else { 42 uint32_t n1 = env->config->nareg - phys; 43 memcpy(env->regs + window, env->phys_regs + phys, 44 n1 * sizeof(uint32_t)); 45 memcpy(env->regs + window + n1, env->phys_regs, 46 (n - n1) * sizeof(uint32_t)); 47 } 48 } 49 50 static void copy_phys_from_window(CPUXtensaState *env, 51 uint32_t phys, uint32_t window, uint32_t n) 52 { 53 assert(phys < env->config->nareg); 54 if (phys + n <= env->config->nareg) { 55 memcpy(env->phys_regs + phys, env->regs + window, 56 n * sizeof(uint32_t)); 57 } else { 58 uint32_t n1 = env->config->nareg - phys; 59 memcpy(env->phys_regs + phys, env->regs + window, 60 n1 * sizeof(uint32_t)); 61 memcpy(env->phys_regs, env->regs + window + n1, 62 (n - n1) * sizeof(uint32_t)); 63 } 64 } 65 66 static inline unsigned windowbase_bound(unsigned a, const CPUXtensaState *env) 67 { 68 return a & (env->config->nareg / 4 - 1); 69 } 70 71 static inline unsigned windowstart_bit(unsigned a, const CPUXtensaState *env) 72 { 73 return 1 << windowbase_bound(a, env); 74 } 75 76 void xtensa_sync_window_from_phys(CPUXtensaState *env) 77 { 78 copy_window_from_phys(env, 0, env->sregs[WINDOW_BASE] * 4, 16); 79 } 80 81 void xtensa_sync_phys_from_window(CPUXtensaState *env) 82 { 83 copy_phys_from_window(env, env->sregs[WINDOW_BASE] * 4, 0, 16); 84 } 85 86 static void xtensa_rotate_window_abs(CPUXtensaState *env, uint32_t position) 87 { 88 xtensa_sync_phys_from_window(env); 89 env->sregs[WINDOW_BASE] = windowbase_bound(position, env); 90 xtensa_sync_window_from_phys(env); 91 } 92 93 void xtensa_rotate_window(CPUXtensaState *env, uint32_t delta) 94 { 95 xtensa_rotate_window_abs(env, env->sregs[WINDOW_BASE] + delta); 96 } 97 98 void HELPER(sync_windowbase)(CPUXtensaState *env) 99 { 100 xtensa_rotate_window_abs(env, env->windowbase_next); 101 } 102 103 void HELPER(entry)(CPUXtensaState *env, uint32_t pc, uint32_t s, uint32_t imm) 104 { 105 int callinc = (env->sregs[PS] & PS_CALLINC) >> PS_CALLINC_SHIFT; 106 107 env->regs[(callinc << 2) | (s & 3)] = env->regs[s] - imm; 108 env->windowbase_next = env->sregs[WINDOW_BASE] + callinc; 109 env->sregs[WINDOW_START] |= windowstart_bit(env->windowbase_next, env); 110 } 111 112 void HELPER(window_check)(CPUXtensaState *env, uint32_t pc, uint32_t w) 113 { 114 uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env); 115 uint32_t windowstart = xtensa_replicate_windowstart(env) >> 116 (env->sregs[WINDOW_BASE] + 1); 117 uint32_t n = ctz32(windowstart) + 1; 118 119 assert(n <= w); 120 121 xtensa_rotate_window(env, n); 122 env->sregs[PS] = (env->sregs[PS] & ~PS_OWB) | 123 (windowbase << PS_OWB_SHIFT) | PS_EXCM; 124 env->sregs[EPC1] = env->pc = pc; 125 126 switch (ctz32(windowstart >> n)) { 127 case 0: 128 HELPER(exception)(env, EXC_WINDOW_OVERFLOW4); 129 break; 130 case 1: 131 HELPER(exception)(env, EXC_WINDOW_OVERFLOW8); 132 break; 133 default: 134 HELPER(exception)(env, EXC_WINDOW_OVERFLOW12); 135 break; 136 } 137 } 138 139 void HELPER(test_ill_retw)(CPUXtensaState *env, uint32_t pc) 140 { 141 int n = (env->regs[0] >> 30) & 0x3; 142 int m = 0; 143 uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env); 144 uint32_t windowstart = env->sregs[WINDOW_START]; 145 146 if (windowstart & windowstart_bit(windowbase - 1, env)) { 147 m = 1; 148 } else if (windowstart & windowstart_bit(windowbase - 2, env)) { 149 m = 2; 150 } else if (windowstart & windowstart_bit(windowbase - 3, env)) { 151 m = 3; 152 } 153 154 if (n == 0 || (m != 0 && m != n)) { 155 qemu_log_mask(LOG_GUEST_ERROR, "Illegal retw instruction(pc = %08x), " 156 "PS = %08x, m = %d, n = %d\n", 157 pc, env->sregs[PS], m, n); 158 HELPER(exception_cause)(env, pc, ILLEGAL_INSTRUCTION_CAUSE); 159 } 160 } 161 162 void HELPER(test_underflow_retw)(CPUXtensaState *env, uint32_t pc) 163 { 164 int n = (env->regs[0] >> 30) & 0x3; 165 166 if (!(env->sregs[WINDOW_START] & 167 windowstart_bit(env->sregs[WINDOW_BASE] - n, env))) { 168 uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env); 169 170 xtensa_rotate_window(env, -n); 171 /* window underflow */ 172 env->sregs[PS] = (env->sregs[PS] & ~PS_OWB) | 173 (windowbase << PS_OWB_SHIFT) | PS_EXCM; 174 env->sregs[EPC1] = env->pc = pc; 175 176 if (n == 1) { 177 HELPER(exception)(env, EXC_WINDOW_UNDERFLOW4); 178 } else if (n == 2) { 179 HELPER(exception)(env, EXC_WINDOW_UNDERFLOW8); 180 } else if (n == 3) { 181 HELPER(exception)(env, EXC_WINDOW_UNDERFLOW12); 182 } 183 } 184 } 185 186 void HELPER(retw)(CPUXtensaState *env, uint32_t a0) 187 { 188 int n = (a0 >> 30) & 0x3; 189 190 xtensa_rotate_window(env, -n); 191 } 192 193 void xtensa_restore_owb(CPUXtensaState *env) 194 { 195 xtensa_rotate_window_abs(env, (env->sregs[PS] & PS_OWB) >> PS_OWB_SHIFT); 196 } 197 198 void HELPER(restore_owb)(CPUXtensaState *env) 199 { 200 xtensa_restore_owb(env); 201 } 202 203 void HELPER(movsp)(CPUXtensaState *env, uint32_t pc) 204 { 205 if ((env->sregs[WINDOW_START] & 206 (windowstart_bit(env->sregs[WINDOW_BASE] - 3, env) | 207 windowstart_bit(env->sregs[WINDOW_BASE] - 2, env) | 208 windowstart_bit(env->sregs[WINDOW_BASE] - 1, env))) == 0) { 209 HELPER(exception_cause)(env, pc, ALLOCA_CAUSE); 210 } 211 } 212