target-cris/helper.c

   1 /*
   2  *  CRIS helper routines.
   3  *
   4  *  Copyright (c) 2007 AXIS Communications AB
   5  *  Written by Edgar E. Iglesias.
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "cpu.h"
  22 #include "mmu.h"
  23 #include "host-utils.h"
  24
  25
  26 //#define CRIS_HELPER_DEBUG
  27
  28
  29 #ifdef CRIS_HELPER_DEBUG
  30 #define D(x) x
  31 #define D_LOG(...) qemu_log(__VA__ARGS__)
  32 #else
  33 #define D(x)
  34 #define D_LOG(...) do { } while (0)
  35 #endif
  36
  37 #if defined(CONFIG_USER_ONLY)
  38
  39 void do_interrupt (CPUCRISState *env)
  40 {
  41         env->exception_index = -1;
  42         env->pregs[PR_ERP] = env->pc;
  43 }
  44
  45 int cpu_cris_handle_mmu_fault(CPUCRISState * env, target_ulong address, int rw,
  46                               int mmu_idx)
  47 {
  48         env->exception_index = 0xaa;
  49         env->pregs[PR_EDA] = address;
  50         cpu_dump_state(env, stderr, fprintf, 0);
  51         return 1;
  52 }
  53
  54 #else /* !CONFIG_USER_ONLY */
  55
  56
  57 static void cris_shift_ccs(CPUCRISState *env)
  58 {
  59         uint32_t ccs;
  60         /* Apply the ccs shift.  */
  61         ccs = env->pregs[PR_CCS];
  62         ccs = ((ccs & 0xc0000000) | ((ccs << 12) >> 2)) & ~0x3ff;
  63         env->pregs[PR_CCS] = ccs;
  64 }
  65
  66 int cpu_cris_handle_mmu_fault (CPUCRISState *env, target_ulong address, int rw,
  67                                int mmu_idx)
  68 {
  69         struct cris_mmu_result res;
  70         int prot, miss;
  71         int r = -1;
  72         target_ulong phy;
  73
  74         D(printf ("%s addr=%x pc=%x rw=%x\n", __func__, address, env->pc, rw));
  75         miss = cris_mmu_translate(&res, env, address & TARGET_PAGE_MASK,
  76                                   rw, mmu_idx, 0);
  77         if (miss)
  78         {
  79                 if (env->exception_index == EXCP_BUSFAULT)
  80                         cpu_abort(env,
  81                                   "CRIS: Illegal recursive bus fault."
  82                                  "addr=%x rw=%d\n",
  83                                  address, rw);
  84
  85                 env->pregs[PR_EDA] = address;
  86                 env->exception_index = EXCP_BUSFAULT;
  87                 env->fault_vector = res.bf_vec;
  88                 r = 1;
  89         }
  90         else
  91         {
  92                 /*
  93                  * Mask off the cache selection bit. The ETRAX busses do not
  94                  * see the top bit.
  95                  */
  96                 phy = res.phy & ~0x80000000;
  97                 prot = res.prot;
  98                 tlb_set_page(env, address & TARGET_PAGE_MASK, phy,
  99                              prot, mmu_idx, TARGET_PAGE_SIZE);
 100                 r = 0;
 101         }
 102         if (r > 0)
 103             D_LOG("%s returns %d irqreq=%x addr=%x phy=%x vec=%x pc=%x\n",
 104                   __func__, r, env->interrupt_request, address, res.phy,
 105                   res.bf_vec, env->pc);
 106         return r;
 107 }
 108
 109 static void do_interruptv10(CPUCRISState *env)
 110 {
 111         int ex_vec = -1;
 112
 113         D_LOG( "exception index=%d interrupt_req=%d\n",
 114                    env->exception_index,
 115                    env->interrupt_request);
 116
 117         assert(!(env->pregs[PR_CCS] & PFIX_FLAG));
 118         switch (env->exception_index)
 119         {
 120                 case EXCP_BREAK:
 121                         /* These exceptions are genereated by the core itself.
 122                            ERP should point to the insn following the brk.  */
 123                         ex_vec = env->trap_vector;
 124                         env->pregs[PRV10_BRP] = env->pc;
 125                         break;
 126
 127                 case EXCP_NMI:
 128                         /* NMI is hardwired to vector zero.  */
 129                         ex_vec = 0;
 130                         env->pregs[PR_CCS] &= ~M_FLAG_V10;
 131                         env->pregs[PRV10_BRP] = env->pc;
 132                         break;
 133
 134                 case EXCP_BUSFAULT:
 135                         cpu_abort(env, "Unhandled busfault");
 136                         break;
 137
 138                 default:
 139                         /* The interrupt controller gives us the vector.  */
 140                         ex_vec = env->interrupt_vector;
 141                         /* Normal interrupts are taken between
 142                            TB's.  env->pc is valid here.  */
 143                         env->pregs[PR_ERP] = env->pc;
 144                         break;
 145         }
 146
 147         if (env->pregs[PR_CCS] & U_FLAG) {
 148                 /* Swap stack pointers.  */
 149                 env->pregs[PR_USP] = env->regs[R_SP];
 150                 env->regs[R_SP] = env->ksp;
 151         }
 152
 153         /* Now that we are in kernel mode, load the handlers address.  */
 154         env->pc = cpu_ldl_code(env, env->pregs[PR_EBP] + ex_vec * 4);
 155         env->locked_irq = 1;
 156         env->pregs[PR_CCS] |= F_FLAG_V10; /* set F.  */
 157
 158         qemu_log_mask(CPU_LOG_INT, "%s isr=%x vec=%x ccs=%x pid=%d erp=%x\n",
 159                       __func__, env->pc, ex_vec,
 160                       env->pregs[PR_CCS],
 161                       env->pregs[PR_PID],
 162                       env->pregs[PR_ERP]);
 163 }
 164
 165 void do_interrupt(CPUCRISState *env)
 166 {
 167         int ex_vec = -1;
 168
 169         if (env->pregs[PR_VR] < 32)
 170                 return do_interruptv10(env);
 171
 172         D_LOG( "exception index=%d interrupt_req=%d\n",
 173                    env->exception_index,
 174                    env->interrupt_request);
 175
 176         switch (env->exception_index)
 177         {
 178                 case EXCP_BREAK:
 179                         /* These exceptions are genereated by the core itself.
 180                            ERP should point to the insn following the brk.  */
 181                         ex_vec = env->trap_vector;
 182                         env->pregs[PR_ERP] = env->pc;
 183                         break;
 184
 185                 case EXCP_NMI:
 186                         /* NMI is hardwired to vector zero.  */
 187                         ex_vec = 0;
 188                         env->pregs[PR_CCS] &= ~M_FLAG_V32;
 189                         env->pregs[PR_NRP] = env->pc;
 190                         break;
 191
 192                 case EXCP_BUSFAULT:
 193                         ex_vec = env->fault_vector;
 194                         env->pregs[PR_ERP] = env->pc;
 195                         break;
 196
 197                 default:
 198                         /* The interrupt controller gives us the vector.  */
 199                         ex_vec = env->interrupt_vector;
 200                         /* Normal interrupts are taken between
 201                            TB's.  env->pc is valid here.  */
 202                         env->pregs[PR_ERP] = env->pc;
 203                         break;
 204         }
 205
 206         /* Fill in the IDX field.  */
 207         env->pregs[PR_EXS] = (ex_vec & 0xff) << 8;
 208
 209         if (env->dslot) {
 210                 D_LOG("excp isr=%x PC=%x ds=%d SP=%x"
 211                           " ERP=%x pid=%x ccs=%x cc=%d %x\n",
 212                           ex_vec, env->pc, env->dslot,
 213                           env->regs[R_SP],
 214                           env->pregs[PR_ERP], env->pregs[PR_PID],
 215                           env->pregs[PR_CCS],
 216                           env->cc_op, env->cc_mask);
 217                 /* We loose the btarget, btaken state here so rexec the
 218                    branch.  */
 219                 env->pregs[PR_ERP] -= env->dslot;
 220                 /* Exception starts with dslot cleared.  */
 221                 env->dslot = 0;
 222         }
 223
 224         if (env->pregs[PR_CCS] & U_FLAG) {
 225                 /* Swap stack pointers.  */
 226                 env->pregs[PR_USP] = env->regs[R_SP];
 227                 env->regs[R_SP] = env->ksp;
 228         }
 229
 230         /* Apply the CRIS CCS shift. Clears U if set.  */
 231         cris_shift_ccs(env);
 232
 233         /* Now that we are in kernel mode, load the handlers address.
 234            This load may not fault, real hw leaves that behaviour as
 235            undefined.  */
 236         env->pc = cpu_ldl_code(env, env->pregs[PR_EBP] + ex_vec * 4);
 237
 238         /* Clear the excption_index to avoid spurios hw_aborts for recursive
 239            bus faults.  */
 240         env->exception_index = -1;
 241
 242         D_LOG("%s isr=%x vec=%x ccs=%x pid=%d erp=%x\n",
 243                    __func__, env->pc, ex_vec,
 244                    env->pregs[PR_CCS],
 245                    env->pregs[PR_PID],
 246                    env->pregs[PR_ERP]);
 247 }
 248
 249 hwaddr cpu_get_phys_page_debug(CPUCRISState * env, target_ulong addr)
 250 {
 251         uint32_t phy = addr;
 252         struct cris_mmu_result res;
 253         int miss;
 254
 255         miss = cris_mmu_translate(&res, env, addr, 0, 0, 1);
 256         /* If D TLB misses, try I TLB.  */
 257         if (miss) {
 258                 miss = cris_mmu_translate(&res, env, addr, 2, 0, 1);
 259         }
 260
 261         if (!miss)
 262                 phy = res.phy;
 263         D(fprintf(stderr, "%s %x -> %x\n", __func__, addr, phy));
 264         return phy;
 265 }
 266 #endif