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 "qemu/main-loop.h" 31 #include "cpu.h" 32 #include "exec/helper-proto.h" 33 #include "qemu/host-utils.h" 34 #include "exec/exec-all.h" 35 36 static void copy_window_from_phys(CPUXtensaState *env, 37 uint32_t window, uint32_t phys, uint32_t n) 38 { 39 assert(phys < env->config->nareg); 40 if (phys + n <= env->config->nareg) { 41 memcpy(env->regs + window, env->phys_regs + phys, 42 n * sizeof(uint32_t)); 43 } else { 44 uint32_t n1 = env->config->nareg - phys; 45 memcpy(env->regs + window, env->phys_regs + phys, 46 n1 * sizeof(uint32_t)); 47 memcpy(env->regs + window + n1, env->phys_regs, 48 (n - n1) * sizeof(uint32_t)); 49 } 50 } 51 52 static void copy_phys_from_window(CPUXtensaState *env, 53 uint32_t phys, uint32_t window, uint32_t n) 54 { 55 assert(phys < env->config->nareg); 56 if (phys + n <= env->config->nareg) { 57 memcpy(env->phys_regs + phys, env->regs + window, 58 n * sizeof(uint32_t)); 59 } else { 60 uint32_t n1 = env->config->nareg - phys; 61 memcpy(env->phys_regs + phys, env->regs + window, 62 n1 * sizeof(uint32_t)); 63 memcpy(env->phys_regs, env->regs + window + n1, 64 (n - n1) * sizeof(uint32_t)); 65 } 66 } 67 68 static inline unsigned windowbase_bound(unsigned a, const CPUXtensaState *env) 69 { 70 return a & (env->config->nareg / 4 - 1); 71 } 72 73 static inline unsigned windowstart_bit(unsigned a, const CPUXtensaState *env) 74 { 75 return 1 << windowbase_bound(a, env); 76 } 77 78 void xtensa_sync_window_from_phys(CPUXtensaState *env) 79 { 80 copy_window_from_phys(env, 0, env->sregs[WINDOW_BASE] * 4, 16); 81 } 82 83 void xtensa_sync_phys_from_window(CPUXtensaState *env) 84 { 85 copy_phys_from_window(env, env->sregs[WINDOW_BASE] * 4, 0, 16); 86 } 87 88 static void xtensa_rotate_window_abs(CPUXtensaState *env, uint32_t position) 89 { 90 xtensa_sync_phys_from_window(env); 91 env->sregs[WINDOW_BASE] = windowbase_bound(position, env); 92 xtensa_sync_window_from_phys(env); 93 } 94 95 void xtensa_rotate_window(CPUXtensaState *env, uint32_t delta) 96 { 97 xtensa_rotate_window_abs(env, env->sregs[WINDOW_BASE] + delta); 98 } 99 100 void HELPER(sync_windowbase)(CPUXtensaState *env) 101 { 102 xtensa_rotate_window_abs(env, env->windowbase_next); 103 } 104 105 void HELPER(entry)(CPUXtensaState *env, uint32_t pc, uint32_t s, uint32_t imm) 106 { 107 int callinc = (env->sregs[PS] & PS_CALLINC) >> PS_CALLINC_SHIFT; 108 109 env->regs[(callinc << 2) | (s & 3)] = env->regs[s] - imm; 110 env->windowbase_next = env->sregs[WINDOW_BASE] + callinc; 111 env->sregs[WINDOW_START] |= windowstart_bit(env->windowbase_next, env); 112 } 113 114 void HELPER(window_check)(CPUXtensaState *env, uint32_t pc, uint32_t w) 115 { 116 uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env); 117 uint32_t windowstart = xtensa_replicate_windowstart(env) >> 118 (env->sregs[WINDOW_BASE] + 1); 119 uint32_t n = ctz32(windowstart) + 1; 120 121 assert(n <= w); 122 123 xtensa_rotate_window(env, n); 124 env->sregs[PS] = (env->sregs[PS] & ~PS_OWB) | 125 (windowbase << PS_OWB_SHIFT) | PS_EXCM; 126 env->sregs[EPC1] = env->pc = pc; 127 128 switch (ctz32(windowstart >> n)) { 129 case 0: 130 HELPER(exception)(env, EXC_WINDOW_OVERFLOW4); 131 break; 132 case 1: 133 HELPER(exception)(env, EXC_WINDOW_OVERFLOW8); 134 break; 135 default: 136 HELPER(exception)(env, EXC_WINDOW_OVERFLOW12); 137 break; 138 } 139 } 140 141 void HELPER(test_ill_retw)(CPUXtensaState *env, uint32_t pc) 142 { 143 int n = (env->regs[0] >> 30) & 0x3; 144 int m = 0; 145 uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env); 146 uint32_t windowstart = env->sregs[WINDOW_START]; 147 148 if (windowstart & windowstart_bit(windowbase - 1, env)) { 149 m = 1; 150 } else if (windowstart & windowstart_bit(windowbase - 2, env)) { 151 m = 2; 152 } else if (windowstart & windowstart_bit(windowbase - 3, env)) { 153 m = 3; 154 } 155 156 if (n == 0 || (m != 0 && m != n)) { 157 qemu_log_mask(LOG_GUEST_ERROR, "Illegal retw instruction(pc = %08x), " 158 "PS = %08x, m = %d, n = %d\n", 159 pc, env->sregs[PS], m, n); 160 HELPER(exception_cause)(env, pc, ILLEGAL_INSTRUCTION_CAUSE); 161 } 162 } 163 164 void HELPER(test_underflow_retw)(CPUXtensaState *env, uint32_t pc) 165 { 166 int n = (env->regs[0] >> 30) & 0x3; 167 168 if (!(env->sregs[WINDOW_START] & 169 windowstart_bit(env->sregs[WINDOW_BASE] - n, env))) { 170 uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env); 171 172 xtensa_rotate_window(env, -n); 173 /* window underflow */ 174 env->sregs[PS] = (env->sregs[PS] & ~PS_OWB) | 175 (windowbase << PS_OWB_SHIFT) | PS_EXCM; 176 env->sregs[EPC1] = env->pc = pc; 177 178 if (n == 1) { 179 HELPER(exception)(env, EXC_WINDOW_UNDERFLOW4); 180 } else if (n == 2) { 181 HELPER(exception)(env, EXC_WINDOW_UNDERFLOW8); 182 } else if (n == 3) { 183 HELPER(exception)(env, EXC_WINDOW_UNDERFLOW12); 184 } 185 } 186 } 187 188 void HELPER(retw)(CPUXtensaState *env, uint32_t a0) 189 { 190 int n = (a0 >> 30) & 0x3; 191 192 xtensa_rotate_window(env, -n); 193 } 194 195 void xtensa_restore_owb(CPUXtensaState *env) 196 { 197 xtensa_rotate_window_abs(env, (env->sregs[PS] & PS_OWB) >> PS_OWB_SHIFT); 198 } 199 200 void HELPER(restore_owb)(CPUXtensaState *env) 201 { 202 xtensa_restore_owb(env); 203 } 204 205 void HELPER(movsp)(CPUXtensaState *env, uint32_t pc) 206 { 207 if ((env->sregs[WINDOW_START] & 208 (windowstart_bit(env->sregs[WINDOW_BASE] - 3, env) | 209 windowstart_bit(env->sregs[WINDOW_BASE] - 2, env) | 210 windowstart_bit(env->sregs[WINDOW_BASE] - 1, env))) == 0) { 211 HELPER(exception_cause)(env, pc, ALLOCA_CAUSE); 212 } 213 } 214