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 "qemu/osdep.h"
  22 #include "cpu.h"
  23 #include "mmu.h"
  24 #include "qemu/host-utils.h"
  25 #include "exec/exec-all.h"
  26 #include "exec/cpu_ldst.h"
  27
  28
  29 //#define CRIS_HELPER_DEBUG
  30
  31
  32 #ifdef CRIS_HELPER_DEBUG
  33 #define D(x) x
  34 #define D_LOG(...) qemu_log(__VA_ARGS__)
  35 #else
  36 #define D(x)
  37 #define D_LOG(...) do { } while (0)
  38 #endif
  39
  40 #if defined(CONFIG_USER_ONLY)
  41
  42 void cris_cpu_do_interrupt(CPUState *cs)
  43 {
  44     CRISCPU *cpu = CRIS_CPU(cs);
  45     CPUCRISState *env = &cpu->env;
  46
  47     cs->exception_index = -1;
  48     env->pregs[PR_ERP] = env->pc;
  49 }
  50
  51 void crisv10_cpu_do_interrupt(CPUState *cs)
  52 {
  53     cris_cpu_do_interrupt(cs);
  54 }
  55
  56 int cris_cpu_handle_mmu_fault(CPUState *cs, vaddr address, int size, int rw,
  57                               int mmu_idx)
  58 {
  59     CRISCPU *cpu = CRIS_CPU(cs);
  60
  61     cs->exception_index = 0xaa;
  62     cpu->env.pregs[PR_EDA] = address;
  63     cpu_dump_state(cs, stderr, fprintf, 0);
  64     return 1;
  65 }
  66
  67 #else /* !CONFIG_USER_ONLY */
  68
  69
  70 static void cris_shift_ccs(CPUCRISState *env)
  71 {
  72     uint32_t ccs;
  73     /* Apply the ccs shift.  */
  74     ccs = env->pregs[PR_CCS];
  75     ccs = ((ccs & 0xc0000000) | ((ccs << 12) >> 2)) & ~0x3ff;
  76     env->pregs[PR_CCS] = ccs;
  77 }
  78
  79 int cris_cpu_handle_mmu_fault(CPUState *cs, vaddr address, int size, int rw,
  80                               int mmu_idx)
  81 {
  82     CRISCPU *cpu = CRIS_CPU(cs);
  83     CPUCRISState *env = &cpu->env;
  84     struct cris_mmu_result res;
  85     int prot, miss;
  86     int r = -1;
  87     target_ulong phy;
  88
  89     qemu_log_mask(CPU_LOG_MMU, "%s addr=%" VADDR_PRIx " pc=%x rw=%x\n",
  90             __func__, address, env->pc, rw);
  91     miss = cris_mmu_translate(&res, env, address & TARGET_PAGE_MASK,
  92                               rw, mmu_idx, 0);
  93     if (miss) {
  94         if (cs->exception_index == EXCP_BUSFAULT) {
  95             cpu_abort(cs,
  96                       "CRIS: Illegal recursive bus fault."
  97                       "addr=%" VADDR_PRIx " rw=%d\n",
  98                       address, rw);
  99         }
 100
 101         env->pregs[PR_EDA] = address;
 102         cs->exception_index = EXCP_BUSFAULT;
 103         env->fault_vector = res.bf_vec;
 104         r = 1;
 105     } else {
 106         /*
 107          * Mask off the cache selection bit. The ETRAX busses do not
 108          * see the top bit.
 109          */
 110         phy = res.phy & ~0x80000000;
 111         prot = res.prot;
 112         tlb_set_page(cs, address & TARGET_PAGE_MASK, phy,
 113                      prot, mmu_idx, TARGET_PAGE_SIZE);
 114         r = 0;
 115     }
 116     if (r > 0) {
 117         qemu_log_mask(CPU_LOG_MMU,
 118                 "%s returns %d irqreq=%x addr=%" VADDR_PRIx " phy=%x vec=%x"
 119                 " pc=%x\n", __func__, r, cs->interrupt_request, address,
 120                 res.phy, res.bf_vec, env->pc);
 121     }
 122     return r;
 123 }
 124
 125 void crisv10_cpu_do_interrupt(CPUState *cs)
 126 {
 127     CRISCPU *cpu = CRIS_CPU(cs);
 128     CPUCRISState *env = &cpu->env;
 129     int ex_vec = -1;
 130
 131     D_LOG("exception index=%d interrupt_req=%d\n",
 132           cs->exception_index,
 133           cs->interrupt_request);
 134
 135     if (env->dslot) {
 136         /* CRISv10 never takes interrupts while in a delay-slot.  */
 137         cpu_abort(cs, "CRIS: Interrupt on delay-slot\n");
 138     }
 139
 140     assert(!(env->pregs[PR_CCS] & PFIX_FLAG));
 141     switch (cs->exception_index) {
 142     case EXCP_BREAK:
 143         /* These exceptions are genereated by the core itself.
 144            ERP should point to the insn following the brk.  */
 145         ex_vec = env->trap_vector;
 146         env->pregs[PRV10_BRP] = env->pc;
 147         break;
 148
 149     case EXCP_NMI:
 150         /* NMI is hardwired to vector zero.  */
 151         ex_vec = 0;
 152         env->pregs[PR_CCS] &= ~M_FLAG_V10;
 153         env->pregs[PRV10_BRP] = env->pc;
 154         break;
 155
 156     case EXCP_BUSFAULT:
 157         cpu_abort(cs, "Unhandled busfault");
 158         break;
 159
 160     default:
 161         /* The interrupt controller gives us the vector.  */
 162         ex_vec = env->interrupt_vector;
 163         /* Normal interrupts are taken between
 164            TB's.  env->pc is valid here.  */
 165         env->pregs[PR_ERP] = env->pc;
 166         break;
 167     }
 168
 169     if (env->pregs[PR_CCS] & U_FLAG) {
 170         /* Swap stack pointers.  */
 171         env->pregs[PR_USP] = env->regs[R_SP];
 172         env->regs[R_SP] = env->ksp;
 173     }
 174
 175     /* Now that we are in kernel mode, load the handlers address.  */
 176     env->pc = cpu_ldl_code(env, env->pregs[PR_EBP] + ex_vec * 4);
 177     env->locked_irq = 1;
 178     env->pregs[PR_CCS] |= F_FLAG_V10; /* set F.  */
 179
 180     qemu_log_mask(CPU_LOG_INT, "%s isr=%x vec=%x ccs=%x pid=%d erp=%x\n",
 181                   __func__, env->pc, ex_vec,
 182                   env->pregs[PR_CCS],
 183                   env->pregs[PR_PID],
 184                   env->pregs[PR_ERP]);
 185 }
 186
 187 void cris_cpu_do_interrupt(CPUState *cs)
 188 {
 189     CRISCPU *cpu = CRIS_CPU(cs);
 190     CPUCRISState *env = &cpu->env;
 191     int ex_vec = -1;
 192
 193     D_LOG("exception index=%d interrupt_req=%d\n",
 194           cs->exception_index,
 195           cs->interrupt_request);
 196
 197     switch (cs->exception_index) {
 198     case EXCP_BREAK:
 199         /* These exceptions are genereated by the core itself.
 200            ERP should point to the insn following the brk.  */
 201         ex_vec = env->trap_vector;
 202         env->pregs[PR_ERP] = env->pc;
 203         break;
 204
 205     case EXCP_NMI:
 206         /* NMI is hardwired to vector zero.  */
 207         ex_vec = 0;
 208         env->pregs[PR_CCS] &= ~M_FLAG_V32;
 209         env->pregs[PR_NRP] = env->pc;
 210         break;
 211
 212     case EXCP_BUSFAULT:
 213         ex_vec = env->fault_vector;
 214         env->pregs[PR_ERP] = env->pc;
 215         break;
 216
 217     default:
 218         /* The interrupt controller gives us the vector.  */
 219         ex_vec = env->interrupt_vector;
 220         /* Normal interrupts are taken between
 221            TB's.  env->pc is valid here.  */
 222         env->pregs[PR_ERP] = env->pc;
 223         break;
 224     }
 225
 226     /* Fill in the IDX field.  */
 227     env->pregs[PR_EXS] = (ex_vec & 0xff) << 8;
 228
 229     if (env->dslot) {
 230         D_LOG("excp isr=%x PC=%x ds=%d SP=%x"
 231               " ERP=%x pid=%x ccs=%x cc=%d %x\n",
 232               ex_vec, env->pc, env->dslot,
 233               env->regs[R_SP],
 234               env->pregs[PR_ERP], env->pregs[PR_PID],
 235               env->pregs[PR_CCS],
 236               env->cc_op, env->cc_mask);
 237         /* We loose the btarget, btaken state here so rexec the
 238            branch.  */
 239         env->pregs[PR_ERP] -= env->dslot;
 240         /* Exception starts with dslot cleared.  */
 241         env->dslot = 0;
 242     }
 243
 244     if (env->pregs[PR_CCS] & U_FLAG) {
 245         /* Swap stack pointers.  */
 246         env->pregs[PR_USP] = env->regs[R_SP];
 247         env->regs[R_SP] = env->ksp;
 248     }
 249
 250     /* Apply the CRIS CCS shift. Clears U if set.  */
 251     cris_shift_ccs(env);
 252
 253     /* Now that we are in kernel mode, load the handlers address.
 254        This load may not fault, real hw leaves that behaviour as
 255        undefined.  */
 256     env->pc = cpu_ldl_code(env, env->pregs[PR_EBP] + ex_vec * 4);
 257
 258     /* Clear the excption_index to avoid spurios hw_aborts for recursive
 259        bus faults.  */
 260     cs->exception_index = -1;
 261
 262     D_LOG("%s isr=%x vec=%x ccs=%x pid=%d erp=%x\n",
 263           __func__, env->pc, ex_vec,
 264           env->pregs[PR_CCS],
 265           env->pregs[PR_PID],
 266           env->pregs[PR_ERP]);
 267 }
 268
 269 hwaddr cris_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
 270 {
 271     CRISCPU *cpu = CRIS_CPU(cs);
 272     uint32_t phy = addr;
 273     struct cris_mmu_result res;
 274     int miss;
 275
 276     miss = cris_mmu_translate(&res, &cpu->env, addr, 0, 0, 1);
 277     /* If D TLB misses, try I TLB.  */
 278     if (miss) {
 279         miss = cris_mmu_translate(&res, &cpu->env, addr, 2, 0, 1);
 280     }
 281
 282     if (!miss) {
 283         phy = res.phy;
 284     }
 285     D(fprintf(stderr, "%s %x -> %x\n", __func__, addr, phy));
 286     return phy;
 287 }
 288 #endif
 289
 290 bool cris_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
 291 {
 292     CPUClass *cc = CPU_GET_CLASS(cs);
 293     CRISCPU *cpu = CRIS_CPU(cs);
 294     CPUCRISState *env = &cpu->env;
 295     bool ret = false;
 296
 297     if (interrupt_request & CPU_INTERRUPT_HARD
 298         && (env->pregs[PR_CCS] & I_FLAG)
 299         && !env->locked_irq) {
 300         cs->exception_index = EXCP_IRQ;
 301         cc->do_interrupt(cs);
 302         ret = true;
 303     }
 304     if (interrupt_request & CPU_INTERRUPT_NMI) {
 305         unsigned int m_flag_archval;
 306         if (env->pregs[PR_VR] < 32) {
 307             m_flag_archval = M_FLAG_V10;
 308         } else {
 309             m_flag_archval = M_FLAG_V32;
 310         }
 311         if ((env->pregs[PR_CCS] & m_flag_archval)) {
 312             cs->exception_index = EXCP_NMI;
 313             cc->do_interrupt(cs);
 314             ret = true;
 315         }
 316     }
 317
 318     return ret;
 319 }