target-microblaze/op_helper.c

   1 /*
   2  *  Microblaze helper routines.
   3  *
   4  *  Copyright (c) 2009 Edgar E. Iglesias <edgar.iglesias@gmail.com>.
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <assert.h>
  21 #include "exec.h"
  22 #include "helper.h"
  23 #include "host-utils.h"
  24
  25 #define D(x)
  26
  27 #if !defined(CONFIG_USER_ONLY)
  28 #define MMUSUFFIX _mmu
  29 #define SHIFT 0
  30 #include "softmmu_template.h"
  31 #define SHIFT 1
  32 #include "softmmu_template.h"
  33 #define SHIFT 2
  34 #include "softmmu_template.h"
  35 #define SHIFT 3
  36 #include "softmmu_template.h"
  37
  38 /* Try to fill the TLB and return an exception if error. If retaddr is
  39    NULL, it means that the function was called in C code (i.e. not
  40    from generated code or from helper.c) */
  41 /* XXX: fix it to restore all registers */
  42 void tlb_fill (target_ulong addr, int is_write, int mmu_idx, void *retaddr)
  43 {
  44     TranslationBlock *tb;
  45     CPUState *saved_env;
  46     unsigned long pc;
  47     int ret;
  48
  49     /* XXX: hack to restore env in all cases, even if not called from
  50        generated code */
  51     saved_env = env;
  52     env = cpu_single_env;
  53
  54     ret = cpu_mb_handle_mmu_fault(env, addr, is_write, mmu_idx, 1);
  55     if (unlikely(ret)) {
  56         if (retaddr) {
  57             /* now we have a real cpu fault */
  58             pc = (unsigned long)retaddr;
  59             tb = tb_find_pc(pc);
  60             if (tb) {
  61                 /* the PC is inside the translated code. It means that we have
  62                    a virtual CPU fault */
  63                 cpu_restore_state(tb, env, pc, NULL);
  64             }
  65         }
  66         cpu_loop_exit();
  67     }
  68     env = saved_env;
  69 }
  70 #endif
  71
  72 void helper_raise_exception(uint32_t index)
  73 {
  74     env->exception_index = index;
  75     cpu_loop_exit();
  76 }
  77
  78 void helper_debug(void)
  79 {
  80     int i;
  81
  82     qemu_log("PC=%8.8x\n", env->sregs[SR_PC]);
  83     qemu_log("rmsr=%x resr=%x rear=%x debug[%x] imm=%x iflags=%x\n",
  84              env->sregs[SR_MSR], env->sregs[SR_ESR], env->sregs[SR_EAR],
  85              env->debug, env->imm, env->iflags);
  86     qemu_log("btaken=%d btarget=%x mode=%s(saved=%s) eip=%d ie=%d\n",
  87              env->btaken, env->btarget,
  88              (env->sregs[SR_MSR] & MSR_UM) ? "user" : "kernel",
  89              (env->sregs[SR_MSR] & MSR_UMS) ? "user" : "kernel",
  90              (env->sregs[SR_MSR] & MSR_EIP),
  91              (env->sregs[SR_MSR] & MSR_IE));
  92     for (i = 0; i < 32; i++) {
  93         qemu_log("r%2.2d=%8.8x ", i, env->regs[i]);
  94         if ((i + 1) % 4 == 0)
  95             qemu_log("\n");
  96     }
  97     qemu_log("\n\n");
  98 }
  99
 100 static inline uint32_t compute_carry(uint32_t a, uint32_t b, uint32_t cin)
 101 {
 102     uint32_t cout = 0;
 103
 104     if ((b == ~0) && cin)
 105         cout = 1;
 106     else if ((~0 - a) < (b + cin))
 107         cout = 1;
 108     return cout;
 109 }
 110
 111 uint32_t helper_cmp(uint32_t a, uint32_t b)
 112 {
 113     uint32_t t;
 114
 115     t = b + ~a + 1;
 116     if ((b & 0x80000000) ^ (a & 0x80000000))
 117         t = (t & 0x7fffffff) | (b & 0x80000000);
 118     return t;
 119 }
 120
 121 uint32_t helper_cmpu(uint32_t a, uint32_t b)
 122 {
 123     uint32_t t;
 124
 125     t = b + ~a + 1;
 126     if ((b & 0x80000000) ^ (a & 0x80000000))
 127         t = (t & 0x7fffffff) | (a & 0x80000000);
 128     return t;
 129 }
 130
 131 uint32_t helper_addkc(uint32_t a, uint32_t b, uint32_t k, uint32_t c)
 132 {
 133     uint32_t d, cf = 0, ncf;
 134
 135     if (c)
 136         cf = env->sregs[SR_MSR] >> 31;
 137     assert(cf == 0 || cf == 1);
 138     d = a + b + cf;
 139
 140     if (!k) {
 141         ncf = compute_carry(a, b, cf);
 142         assert(ncf == 0 || ncf == 1);
 143         if (ncf)
 144             env->sregs[SR_MSR] |= MSR_C | MSR_CC;
 145         else
 146             env->sregs[SR_MSR] &= ~(MSR_C | MSR_CC);
 147     }
 148     D(qemu_log("%x = %x + %x cf=%d ncf=%d k=%d c=%d\n",
 149                d, a, b, cf, ncf, k, c));
 150     return d;
 151 }
 152
 153 uint32_t helper_subkc(uint32_t a, uint32_t b, uint32_t k, uint32_t c)
 154 {
 155     uint32_t d, cf = 1, ncf;
 156
 157     if (c)
 158         cf = env->sregs[SR_MSR] >> 31;
 159     assert(cf == 0 || cf == 1);
 160     d = b + ~a + cf;
 161
 162     if (!k) {
 163         ncf = compute_carry(b, ~a, cf);
 164         assert(ncf == 0 || ncf == 1);
 165         if (ncf)
 166             env->sregs[SR_MSR] |= MSR_C | MSR_CC;
 167         else
 168             env->sregs[SR_MSR] &= ~(MSR_C | MSR_CC);
 169     }
 170     D(qemu_log("%x = %x + %x cf=%d ncf=%d k=%d c=%d\n",
 171                d, a, b, cf, ncf, k, c));
 172     return d;
 173 }
 174
 175 static inline int div_prepare(uint32_t a, uint32_t b)
 176 {
 177     if (b == 0) {
 178         env->sregs[SR_MSR] |= MSR_DZ;
 179
 180         if ((env->sregs[SR_MSR] & MSR_EE)
 181             && !(env->pvr.regs[2] & PVR2_DIV_ZERO_EXC_MASK)) {
 182             env->sregs[SR_ESR] = ESR_EC_DIVZERO;
 183             helper_raise_exception(EXCP_HW_EXCP);
 184         }
 185         return 0;
 186     }
 187     env->sregs[SR_MSR] &= ~MSR_DZ;
 188     return 1;
 189 }
 190
 191 uint32_t helper_divs(uint32_t a, uint32_t b)
 192 {
 193     if (!div_prepare(a, b))
 194         return 0;
 195     return (int32_t)a / (int32_t)b;
 196 }
 197
 198 uint32_t helper_divu(uint32_t a, uint32_t b)
 199 {
 200     if (!div_prepare(a, b))
 201         return 0;
 202     return a / b;
 203 }
 204
 205 uint32_t helper_pcmpbf(uint32_t a, uint32_t b)
 206 {
 207     unsigned int i;
 208     uint32_t mask = 0xff000000;
 209
 210     for (i = 0; i < 4; i++) {
 211         if ((a & mask) == (b & mask))
 212             return i + 1;
 213         mask >>= 8;
 214     }
 215     return 0;
 216 }
 217
 218 void helper_memalign(uint32_t addr, uint32_t dr, uint32_t wr, uint32_t mask)
 219 {
 220     if (addr & mask) {
 221             qemu_log_mask(CPU_LOG_INT,
 222                           "unaligned access addr=%x mask=%x, wr=%d dr=r%d\n",
 223                           addr, mask, wr, dr);
 224             env->sregs[SR_EAR] = addr;
 225             env->sregs[SR_ESR] = ESR_EC_UNALIGNED_DATA | (wr << 10) \
 226                                  | (dr & 31) << 5;
 227             if (mask == 3) {
 228                 env->sregs[SR_ESR] |= 1 << 11;
 229             }
 230             if (!(env->sregs[SR_MSR] & MSR_EE)) {
 231                 return;
 232             }
 233             helper_raise_exception(EXCP_HW_EXCP);
 234     }
 235 }
 236
 237 #if !defined(CONFIG_USER_ONLY)
 238 /* Writes/reads to the MMU's special regs end up here.  */
 239 uint32_t helper_mmu_read(uint32_t rn)
 240 {
 241     return mmu_read(env, rn);
 242 }
 243
 244 void helper_mmu_write(uint32_t rn, uint32_t v)
 245 {
 246     mmu_write(env, rn, v);
 247 }
 248 #endif
 249
 250 void do_unassigned_access(target_phys_addr_t addr, int is_write, int is_exec,
 251                           int is_asi, int size)
 252 {
 253     CPUState *saved_env;
 254     /* XXX: hack to restore env in all cases, even if not called from
 255        generated code */
 256     saved_env = env;
 257     env = cpu_single_env;
 258     qemu_log_mask(CPU_LOG_INT, "Unassigned " TARGET_FMT_plx " wr=%d exe=%d\n",
 259              addr, is_write, is_exec);
 260     if (!(env->sregs[SR_MSR] & MSR_EE)) {
 261         env = saved_env;
 262         return;
 263     }
 264
 265     env->sregs[SR_EAR] = addr;
 266     if (is_exec) {
 267         if ((env->pvr.regs[2] & PVR2_IOPB_BUS_EXC_MASK)) {
 268             env->sregs[SR_ESR] = ESR_EC_INSN_BUS;
 269             helper_raise_exception(EXCP_HW_EXCP);
 270         }
 271     } else {
 272         if ((env->pvr.regs[2] & PVR2_DOPB_BUS_EXC_MASK)) {
 273             env->sregs[SR_ESR] = ESR_EC_DATA_BUS;
 274             helper_raise_exception(EXCP_HW_EXCP);
 275         }
 276     }
 277     env = saved_env;
 278 }