| 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 | } |