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 <stdio.h>
  22 #include <string.h>
  23
  24 #include "config.h"
  25 #include "cpu.h"
  26 #include "mmu.h"
  27 #include "host-utils.h"
  28
  29
  30 //#define CRIS_HELPER_DEBUG
  31
  32
  33 #ifdef CRIS_HELPER_DEBUG
  34 #define D(x) x
  35 #define D_LOG(...) qemu_log(__VA__ARGS__)
  36 #else
  37 #define D(x)
  38 #define D_LOG(...) do { } while (0)
  39 #endif
  40
  41 #if defined(CONFIG_USER_ONLY)
  42
  43 void do_interrupt (CPUState *env)
  44 {
  45         env->exception_index = -1;
  46         env->pregs[PR_ERP] = env->pc;
  47 }
  48
  49 int cpu_cris_handle_mmu_fault(CPUState * env, target_ulong address, int rw,
  50                               int mmu_idx)
  51 {
  52         env->exception_index = 0xaa;
  53         env->pregs[PR_EDA] = address;
  54         cpu_dump_state(env, stderr, fprintf, 0);
  55         return 1;
  56 }
  57
  58 #else /* !CONFIG_USER_ONLY */
  59
  60
  61 static void cris_shift_ccs(CPUState *env)
  62 {
  63         uint32_t ccs;
  64         /* Apply the ccs shift.  */
  65         ccs = env->pregs[PR_CCS];
  66         ccs = ((ccs & 0xc0000000) | ((ccs << 12) >> 2)) & ~0x3ff;
  67         env->pregs[PR_CCS] = ccs;
  68 }
  69
  70 int cpu_cris_handle_mmu_fault (CPUState *env, target_ulong address, int rw,
  71                                int mmu_idx)
  72 {
  73         struct cris_mmu_result res;
  74         int prot, miss;
  75         int r = -1;
  76         target_ulong phy;
  77
  78         D(printf ("%s addr=%x pc=%x rw=%x\n", __func__, address, env->pc, rw));
  79         miss = cris_mmu_translate(&res, env, address & TARGET_PAGE_MASK,
  80                                   rw, mmu_idx, 0);
  81         if (miss)
  82         {
  83                 if (env->exception_index == EXCP_BUSFAULT)
  84                         cpu_abort(env,
  85                                   "CRIS: Illegal recursive bus fault."
  86                                  "addr=%x rw=%d\n",
  87                                  address, rw);
  88
  89                 env->pregs[PR_EDA] = address;
  90                 env->exception_index = EXCP_BUSFAULT;
  91                 env->fault_vector = res.bf_vec;
  92                 r = 1;
  93         }
  94         else
  95         {
  96                 /*
  97                  * Mask off the cache selection bit. The ETRAX busses do not
  98                  * see the top bit.
  99                  */
 100                 phy = res.phy & ~0x80000000;
 101                 prot = res.prot;
 102                 tlb_set_page(env, address & TARGET_PAGE_MASK, phy,
 103                              prot, mmu_idx, TARGET_PAGE_SIZE);
 104                 r = 0;
 105         }
 106         if (r > 0)
 107             D_LOG("%s returns %d irqreq=%x addr=%x phy=%x vec=%x pc=%x\n",
 108                   __func__, r, env->interrupt_request, address, res.phy,
 109                   res.bf_vec, env->pc);
 110         return r;
 111 }
 112
 113 static void do_interruptv10(CPUState *env)
 114 {
 115         int ex_vec = -1;
 116
 117         D_LOG( "exception index=%d interrupt_req=%d\n",
 118                    env->exception_index,
 119                    env->interrupt_request);
 120
 121         assert(!(env->pregs[PR_CCS] & PFIX_FLAG));
 122         switch (env->exception_index)
 123         {
 124                 case EXCP_BREAK:
 125                         /* These exceptions are genereated by the core itself.
 126                            ERP should point to the insn following the brk.  */
 127                         ex_vec = env->trap_vector;
 128                         env->pregs[PR_ERP] = env->pc;
 129                         break;
 130
 131                 case EXCP_NMI:
 132                         /* NMI is hardwired to vector zero.  */
 133                         ex_vec = 0;
 134                         env->pregs[PR_CCS] &= ~M_FLAG;
 135                         env->pregs[PR_NRP] = env->pc;
 136                         break;
 137
 138                 case EXCP_BUSFAULT:
 139                         cpu_abort(env, "Unhandled busfault");
 140                         break;
 141
 142                 default:
 143                         /* The interrupt controller gives us the vector.  */
 144                         ex_vec = env->interrupt_vector;
 145                         /* Normal interrupts are taken between
 146                            TB's.  env->pc is valid here.  */
 147                         env->pregs[PR_ERP] = env->pc;
 148                         break;
 149         }
 150
 151         if (env->pregs[PR_CCS] & U_FLAG) {
 152                 /* Swap stack pointers.  */
 153                 env->pregs[PR_USP] = env->regs[R_SP];
 154                 env->regs[R_SP] = env->ksp;
 155         }
 156
 157         /* Now that we are in kernel mode, load the handlers address.  */
 158         env->pc = ldl_code(env->pregs[PR_EBP] + ex_vec * 4);
 159         env->locked_irq = 1;
 160
 161         qemu_log_mask(CPU_LOG_INT, "%s isr=%x vec=%x ccs=%x pid=%d erp=%x\n",
 162                       __func__, env->pc, ex_vec,
 163                       env->pregs[PR_CCS],
 164                       env->pregs[PR_PID],
 165                       env->pregs[PR_ERP]);
 166 }
 167
 168 void do_interrupt(CPUState *env)
 169 {
 170         int ex_vec = -1;
 171
 172         if (env->pregs[PR_VR] < 32)
 173                 return do_interruptv10(env);
 174
 175         D_LOG( "exception index=%d interrupt_req=%d\n",
 176                    env->exception_index,
 177                    env->interrupt_request);
 178
 179         switch (env->exception_index)
 180         {
 181                 case EXCP_BREAK:
 182                         /* These exceptions are genereated by the core itself.
 183                            ERP should point to the insn following the brk.  */
 184                         ex_vec = env->trap_vector;
 185                         env->pregs[PR_ERP] = env->pc;
 186                         break;
 187
 188                 case EXCP_NMI:
 189                         /* NMI is hardwired to vector zero.  */
 190                         ex_vec = 0;
 191                         env->pregs[PR_CCS] &= ~M_FLAG;
 192                         env->pregs[PR_NRP] = env->pc;
 193                         break;
 194
 195                 case EXCP_BUSFAULT:
 196                         ex_vec = env->fault_vector;
 197                         env->pregs[PR_ERP] = env->pc;
 198                         break;
 199
 200                 default:
 201                         /* The interrupt controller gives us the vector.  */
 202                         ex_vec = env->interrupt_vector;
 203                         /* Normal interrupts are taken between
 204                            TB's.  env->pc is valid here.  */
 205                         env->pregs[PR_ERP] = env->pc;
 206                         break;
 207         }
 208
 209         /* Fill in the IDX field.  */
 210         env->pregs[PR_EXS] = (ex_vec & 0xff) << 8;
 211
 212         if (env->dslot) {
 213                 D_LOG("excp isr=%x PC=%x ds=%d SP=%x"
 214                           " ERP=%x pid=%x ccs=%x cc=%d %x\n",
 215                           ex_vec, env->pc, env->dslot,
 216                           env->regs[R_SP],
 217                           env->pregs[PR_ERP], env->pregs[PR_PID],
 218                           env->pregs[PR_CCS],
 219                           env->cc_op, env->cc_mask);
 220                 /* We loose the btarget, btaken state here so rexec the
 221                    branch.  */
 222                 env->pregs[PR_ERP] -= env->dslot;
 223                 /* Exception starts with dslot cleared.  */
 224                 env->dslot = 0;
 225         }
 226
 227         if (env->pregs[PR_CCS] & U_FLAG) {
 228                 /* Swap stack pointers.  */
 229                 env->pregs[PR_USP] = env->regs[R_SP];
 230                 env->regs[R_SP] = env->ksp;
 231         }
 232
 233         /* Apply the CRIS CCS shift. Clears U if set.  */
 234         cris_shift_ccs(env);
 235
 236         /* Now that we are in kernel mode, load the handlers address.
 237            This load may not fault, real hw leaves that behaviour as
 238            undefined.  */
 239         env->pc = ldl_code(env->pregs[PR_EBP] + ex_vec * 4);
 240
 241         /* Clear the excption_index to avoid spurios hw_aborts for recursive
 242            bus faults.  */
 243         env->exception_index = -1;
 244
 245         D_LOG("%s isr=%x vec=%x ccs=%x pid=%d erp=%x\n",
 246                    __func__, env->pc, ex_vec,
 247                    env->pregs[PR_CCS],
 248                    env->pregs[PR_PID],
 249                    env->pregs[PR_ERP]);
 250 }
 251
 252 target_phys_addr_t cpu_get_phys_page_debug(CPUState * env, target_ulong addr)
 253 {
 254         uint32_t phy = addr;
 255         struct cris_mmu_result res;
 256         int miss;
 257
 258         miss = cris_mmu_translate(&res, env, addr, 0, 0, 1);
 259         /* If D TLB misses, try I TLB.  */
 260         if (miss) {
 261                 miss = cris_mmu_translate(&res, env, addr, 2, 0, 1);
 262         }
 263
 264         if (!miss)
 265                 phy = res.phy;
 266         D(fprintf(stderr, "%s %x -> %x\n", __func__, addr, phy));
 267         return phy;
 268 }
 269 #endif