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/main-loop.h" 30 #include "cpu.h" 31 #include "exec/helper-proto.h" 32 #include "qemu/host-utils.h" 33 #include "exec/exec-all.h" 34 35 static void copy_window_from_phys(CPUXtensaState *env, 36 uint32_t window, uint32_t phys, uint32_t n) 37 { 38 assert(phys < env->config->nareg); 39 if (phys + n <= env->config->nareg) { 40 memcpy(env->regs + window, env->phys_regs + phys, 41 n * sizeof(uint32_t)); 42 } else { 43 uint32_t n1 = env->config->nareg - phys; 44 memcpy(env->regs + window, env->phys_regs + phys, 45 n1 * sizeof(uint32_t)); 46 memcpy(env->regs + window + n1, env->phys_regs, 47 (n - n1) * sizeof(uint32_t)); 48 } 49 } 50 51 static void copy_phys_from_window(CPUXtensaState *env, 52 uint32_t phys, uint32_t window, uint32_t n) 53 { 54 assert(phys < env->config->nareg); 55 if (phys + n <= env->config->nareg) { 56 memcpy(env->phys_regs + phys, env->regs + window, 57 n * sizeof(uint32_t)); 58 } else { 59 uint32_t n1 = env->config->nareg - phys; 60 memcpy(env->phys_regs + phys, env->regs + window, 61 n1 * sizeof(uint32_t)); 62 memcpy(env->phys_regs, env->regs + window + n1, 63 (n - n1) * sizeof(uint32_t)); 64 } 65 } 66 67 static inline unsigned windowbase_bound(unsigned a, const CPUXtensaState *env) 68 { 69 return a & (env->config->nareg / 4 - 1); 70 } 71 72 static inline unsigned windowstart_bit(unsigned a, const CPUXtensaState *env) 73 { 74 return 1 << windowbase_bound(a, env); 75 } 76 77 void xtensa_sync_window_from_phys(CPUXtensaState *env) 78 { 79 copy_window_from_phys(env, 0, env->sregs[WINDOW_BASE] * 4, 16); 80 } 81 82 void xtensa_sync_phys_from_window(CPUXtensaState *env) 83 { 84 copy_phys_from_window(env, env->sregs[WINDOW_BASE] * 4, 0, 16); 85 } 86 87 static void xtensa_rotate_window_abs(CPUXtensaState *env, uint32_t position) 88 { 89 xtensa_sync_phys_from_window(env); 90 env->sregs[WINDOW_BASE] = windowbase_bound(position, env); 91 xtensa_sync_window_from_phys(env); 92 } 93 94 void xtensa_rotate_window(CPUXtensaState *env, uint32_t delta) 95 { 96 xtensa_rotate_window_abs(env, env->sregs[WINDOW_BASE] + delta); 97 } 98 99 void HELPER(sync_windowbase)(CPUXtensaState *env) 100 { 101 xtensa_rotate_window_abs(env, env->windowbase_next); 102 } 103 104 void HELPER(entry)(CPUXtensaState *env, uint32_t pc, uint32_t s, uint32_t imm) 105 { 106 int callinc = (env->sregs[PS] & PS_CALLINC) >> PS_CALLINC_SHIFT; 107 108 env->regs[(callinc << 2) | (s & 3)] = env->regs[s] - imm; 109 env->windowbase_next = env->sregs[WINDOW_BASE] + callinc; 110 env->sregs[WINDOW_START] |= windowstart_bit(env->windowbase_next, env); 111 } 112 113 void HELPER(window_check)(CPUXtensaState *env, uint32_t pc, uint32_t w) 114 { 115 uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env); 116 uint32_t windowstart = xtensa_replicate_windowstart(env) >> 117 (env->sregs[WINDOW_BASE] + 1); 118 uint32_t n = ctz32(windowstart) + 1; 119 120 assert(n <= w); 121 122 xtensa_rotate_window(env, n); 123 env->sregs[PS] = (env->sregs[PS] & ~PS_OWB) | 124 (windowbase << PS_OWB_SHIFT) | PS_EXCM; 125 env->sregs[EPC1] = env->pc = pc; 126 127 switch (ctz32(windowstart >> n)) { 128 case 0: 129 HELPER(exception)(env, EXC_WINDOW_OVERFLOW4); 130 break; 131 case 1: 132 HELPER(exception)(env, EXC_WINDOW_OVERFLOW8); 133 break; 134 default: 135 HELPER(exception)(env, EXC_WINDOW_OVERFLOW12); 136 break; 137 } 138 } 139 140 void HELPER(test_ill_retw)(CPUXtensaState *env, uint32_t pc) 141 { 142 int n = (env->regs[0] >> 30) & 0x3; 143 int m = 0; 144 uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env); 145 uint32_t windowstart = env->sregs[WINDOW_START]; 146 147 if (windowstart & windowstart_bit(windowbase - 1, env)) { 148 m = 1; 149 } else if (windowstart & windowstart_bit(windowbase - 2, env)) { 150 m = 2; 151 } else if (windowstart & windowstart_bit(windowbase - 3, env)) { 152 m = 3; 153 } 154 155 if (n == 0 || (m != 0 && m != n)) { 156 qemu_log_mask(LOG_GUEST_ERROR, "Illegal retw instruction(pc = %08x), " 157 "PS = %08x, m = %d, n = %d\n", 158 pc, env->sregs[PS], m, n); 159 HELPER(exception_cause)(env, pc, ILLEGAL_INSTRUCTION_CAUSE); 160 } 161 } 162 163 void HELPER(test_underflow_retw)(CPUXtensaState *env, uint32_t pc) 164 { 165 int n = (env->regs[0] >> 30) & 0x3; 166 167 if (!(env->sregs[WINDOW_START] & 168 windowstart_bit(env->sregs[WINDOW_BASE] - n, env))) { 169 uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env); 170 171 xtensa_rotate_window(env, -n); 172 /* window underflow */ 173 env->sregs[PS] = (env->sregs[PS] & ~PS_OWB) | 174 (windowbase << PS_OWB_SHIFT) | PS_EXCM; 175 env->sregs[EPC1] = env->pc = pc; 176 177 if (n == 1) { 178 HELPER(exception)(env, EXC_WINDOW_UNDERFLOW4); 179 } else if (n == 2) { 180 HELPER(exception)(env, EXC_WINDOW_UNDERFLOW8); 181 } else if (n == 3) { 182 HELPER(exception)(env, EXC_WINDOW_UNDERFLOW12); 183 } 184 } 185 } 186 187 void HELPER(retw)(CPUXtensaState *env, uint32_t a0) 188 { 189 int n = (a0 >> 30) & 0x3; 190 191 xtensa_rotate_window(env, -n); 192 } 193 194 void xtensa_restore_owb(CPUXtensaState *env) 195 { 196 xtensa_rotate_window_abs(env, (env->sregs[PS] & PS_OWB) >> PS_OWB_SHIFT); 197 } 198 199 void HELPER(restore_owb)(CPUXtensaState *env) 200 { 201 xtensa_restore_owb(env); 202 } 203 204 void HELPER(movsp)(CPUXtensaState *env, uint32_t pc) 205 { 206 if ((env->sregs[WINDOW_START] & 207 (windowstart_bit(env->sregs[WINDOW_BASE] - 3, env) | 208 windowstart_bit(env->sregs[WINDOW_BASE] - 2, env) | 209 windowstart_bit(env->sregs[WINDOW_BASE] - 1, env))) == 0) { 210 HELPER(exception_cause)(env, pc, ALLOCA_CAUSE); 211 } 212 } 213