target/nios2/cpu.h

   1 /*
   2  * Altera Nios II virtual CPU header
   3  *
   4  * Copyright (c) 2012 Chris Wulff <crwulff@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 2.1 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
  18  * <http://www.gnu.org/licenses/lgpl-2.1.html>
  19  */
  20
  21 #ifndef NIOS2_CPU_H
  22 #define NIOS2_CPU_H
  23
  24 #include "exec/cpu-defs.h"
  25 #include "hw/core/cpu.h"
  26 #include "hw/registerfields.h"
  27 #include "qom/object.h"
  28
  29 typedef struct CPUArchState CPUNios2State;
  30 #if !defined(CONFIG_USER_ONLY)
  31 #include "mmu.h"
  32 #endif
  33
  34 #define TYPE_NIOS2_CPU "nios2-cpu"
  35
  36 OBJECT_DECLARE_CPU_TYPE(Nios2CPU, Nios2CPUClass, NIOS2_CPU)
  37
  38 /**
  39  * Nios2CPUClass:
  40  * @parent_reset: The parent class' reset handler.
  41  *
  42  * A Nios2 CPU model.
  43  */
  44 struct Nios2CPUClass {
  45     /*< private >*/
  46     CPUClass parent_class;
  47     /*< public >*/
  48
  49     DeviceRealize parent_realize;
  50     DeviceReset parent_reset;
  51 };
  52
  53 #define TARGET_HAS_ICE 1
  54
  55 /* Configuration options for Nios II */
  56 #define RESET_ADDRESS         0x00000000
  57 #define EXCEPTION_ADDRESS     0x00000004
  58 #define FAST_TLB_MISS_ADDRESS 0x00000008
  59
  60 #define NUM_GP_REGS 32
  61 #define NUM_CR_REGS 32
  62
  63 #ifndef CONFIG_USER_ONLY
  64 /* 63 shadow register sets; index 0 is the primary register set. */
  65 #define NUM_REG_SETS 64
  66 #endif
  67
  68 /* General purpose register aliases */
  69 enum {
  70     R_ZERO   = 0,
  71     R_AT     = 1,
  72     R_RET0   = 2,
  73     R_RET1   = 3,
  74     R_ARG0   = 4,
  75     R_ARG1   = 5,
  76     R_ARG2   = 6,
  77     R_ARG3   = 7,
  78     R_ET     = 24,
  79     R_BT     = 25,
  80     R_GP     = 26,
  81     R_SP     = 27,
  82     R_FP     = 28,
  83     R_EA     = 29,
  84     R_BA     = 30,
  85     R_SSTATUS = 30,
  86     R_RA     = 31,
  87 };
  88
  89 /* Control register aliases */
  90 enum {
  91     CR_STATUS        = 0,
  92     CR_ESTATUS       = 1,
  93     CR_BSTATUS       = 2,
  94     CR_IENABLE       = 3,
  95     CR_IPENDING      = 4,
  96     CR_CPUID         = 5,
  97     CR_EXCEPTION     = 7,
  98     CR_PTEADDR       = 8,
  99     CR_TLBACC        = 9,
 100     CR_TLBMISC       = 10,
 101     CR_ENCINJ        = 11,
 102     CR_BADADDR       = 12,
 103     CR_CONFIG        = 13,
 104     CR_MPUBASE       = 14,
 105     CR_MPUACC        = 15,
 106 };
 107
 108 FIELD(CR_STATUS, PIE, 0, 1)
 109 FIELD(CR_STATUS, U, 1, 1)
 110 FIELD(CR_STATUS, EH, 2, 1)
 111 FIELD(CR_STATUS, IH, 3, 1)
 112 FIELD(CR_STATUS, IL, 4, 6)
 113 FIELD(CR_STATUS, CRS, 10, 6)
 114 FIELD(CR_STATUS, PRS, 16, 6)
 115 FIELD(CR_STATUS, NMI, 22, 1)
 116 FIELD(CR_STATUS, RSIE, 23, 1)
 117 FIELD(CR_STATUS, SRS, 31, 1)  /* only in sstatus */
 118
 119 #define CR_STATUS_PIE    R_CR_STATUS_PIE_MASK
 120 #define CR_STATUS_U      R_CR_STATUS_U_MASK
 121 #define CR_STATUS_EH     R_CR_STATUS_EH_MASK
 122 #define CR_STATUS_IH     R_CR_STATUS_IH_MASK
 123 #define CR_STATUS_NMI    R_CR_STATUS_NMI_MASK
 124 #define CR_STATUS_RSIE   R_CR_STATUS_RSIE_MASK
 125 #define CR_STATUS_SRS    R_CR_STATUS_SRS_MASK
 126
 127 FIELD(CR_EXCEPTION, CAUSE, 2, 5)
 128 FIELD(CR_EXCEPTION, ECCFTL, 31, 1)
 129
 130 FIELD(CR_PTEADDR, VPN, 2, 20)
 131 FIELD(CR_PTEADDR, PTBASE, 22, 10)
 132
 133 FIELD(CR_TLBACC, PFN, 0, 20)
 134 FIELD(CR_TLBACC, G, 20, 1)
 135 FIELD(CR_TLBACC, X, 21, 1)
 136 FIELD(CR_TLBACC, W, 22, 1)
 137 FIELD(CR_TLBACC, R, 23, 1)
 138 FIELD(CR_TLBACC, C, 24, 1)
 139 FIELD(CR_TLBACC, IG, 25, 7)
 140
 141 #define CR_TLBACC_C      R_CR_TLBACC_C_MASK
 142 #define CR_TLBACC_R      R_CR_TLBACC_R_MASK
 143 #define CR_TLBACC_W      R_CR_TLBACC_W_MASK
 144 #define CR_TLBACC_X      R_CR_TLBACC_X_MASK
 145 #define CR_TLBACC_G      R_CR_TLBACC_G_MASK
 146
 147 FIELD(CR_TLBMISC, D, 0, 1)
 148 FIELD(CR_TLBMISC, PERM, 1, 1)
 149 FIELD(CR_TLBMISC, BAD, 2, 1)
 150 FIELD(CR_TLBMISC, DBL, 3, 1)
 151 FIELD(CR_TLBMISC, PID, 4, 14)
 152 FIELD(CR_TLBMISC, WE, 18, 1)
 153 FIELD(CR_TLBMISC, RD, 19, 1)
 154 FIELD(CR_TLBMISC, WAY, 20, 4)
 155 FIELD(CR_TLBMISC, EE, 24, 1)
 156
 157 #define CR_TLBMISC_EE    R_CR_TLBMISC_EE_MASK
 158 #define CR_TLBMISC_RD    R_CR_TLBMISC_RD_MASK
 159 #define CR_TLBMISC_WE    R_CR_TLBMISC_WE_MASK
 160 #define CR_TLBMISC_DBL   R_CR_TLBMISC_DBL_MASK
 161 #define CR_TLBMISC_BAD   R_CR_TLBMISC_BAD_MASK
 162 #define CR_TLBMISC_PERM  R_CR_TLBMISC_PERM_MASK
 163 #define CR_TLBMISC_D     R_CR_TLBMISC_D_MASK
 164
 165 /* Exceptions */
 166 #define EXCP_BREAK    0x1000
 167 #define EXCP_SEMIHOST 0x1001
 168 #define EXCP_RESET    0
 169 #define EXCP_PRESET   1
 170 #define EXCP_IRQ      2
 171 #define EXCP_TRAP     3
 172 #define EXCP_UNIMPL   4
 173 #define EXCP_ILLEGAL  5
 174 #define EXCP_UNALIGN  6
 175 #define EXCP_UNALIGND 7
 176 #define EXCP_DIV      8
 177 #define EXCP_SUPERA_X 9
 178 #define EXCP_SUPERI   10
 179 #define EXCP_SUPERA_D 11
 180 #define EXCP_TLB_X    12
 181 #define EXCP_TLB_D    (0x1000 | EXCP_TLB_X)
 182 #define EXCP_PERM_X   13
 183 #define EXCP_PERM_R   14
 184 #define EXCP_PERM_W   15
 185 #define EXCP_MPUI     16
 186 #define EXCP_MPUD     17
 187
 188 struct CPUArchState {
 189 #ifdef CONFIG_USER_ONLY
 190     uint32_t regs[NUM_GP_REGS];
 191 #else
 192     uint32_t shadow_regs[NUM_REG_SETS][NUM_GP_REGS];
 193     /* Pointer into shadow_regs for the current register set. */
 194     uint32_t *regs;
 195 #endif
 196     uint32_t ctrl[NUM_CR_REGS];
 197     uint32_t pc;
 198
 199 #if !defined(CONFIG_USER_ONLY)
 200     Nios2MMU mmu;
 201 #endif
 202     int error_code;
 203 };
 204
 205 typedef struct {
 206     uint32_t writable;
 207     uint32_t readonly;
 208 } ControlRegState;
 209
 210 /**
 211  * Nios2CPU:
 212  * @env: #CPUNios2State
 213  *
 214  * A Nios2 CPU.
 215  */
 216 struct ArchCPU {
 217     /*< private >*/
 218     CPUState parent_obj;
 219     /*< public >*/
 220
 221     CPUNegativeOffsetState neg;
 222     CPUNios2State env;
 223
 224     bool diverr_present;
 225     bool mmu_present;
 226     bool eic_present;
 227
 228     uint32_t pid_num_bits;
 229     uint32_t tlb_num_ways;
 230     uint32_t tlb_num_entries;
 231
 232     /* Addresses that are hard-coded in the FPGA build settings */
 233     uint32_t reset_addr;
 234     uint32_t exception_addr;
 235     uint32_t fast_tlb_miss_addr;
 236
 237     /* Bits within each control register which are reserved or readonly. */
 238     ControlRegState cr_state[NUM_CR_REGS];
 239
 240     /* External Interrupt Controller Interface */
 241     uint32_t rha; /* Requested handler address */
 242     uint32_t ril; /* Requested interrupt level */
 243     uint32_t rrs; /* Requested register set */
 244     bool rnmi;    /* Requested nonmaskable interrupt */
 245 };
 246
 247
 248 static inline bool nios2_cr_reserved(const ControlRegState *s)
 249 {
 250     return (s->writable | s->readonly) == 0;
 251 }
 252
 253 static inline void nios2_update_crs(CPUNios2State *env)
 254 {
 255 #ifndef CONFIG_USER_ONLY
 256     unsigned crs = FIELD_EX32(env->ctrl[CR_STATUS], CR_STATUS, CRS);
 257     env->regs = env->shadow_regs[crs];
 258 #endif
 259 }
 260
 261 void nios2_tcg_init(void);
 262 void nios2_cpu_do_interrupt(CPUState *cs);
 263 void dump_mmu(CPUNios2State *env);
 264 void nios2_cpu_dump_state(CPUState *cpu, FILE *f, int flags);
 265 hwaddr nios2_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
 266 G_NORETURN void nios2_cpu_do_unaligned_access(CPUState *cpu, vaddr addr,
 267                                               MMUAccessType access_type, int mmu_idx,
 268                                               uintptr_t retaddr);
 269 G_NORETURN void nios2_cpu_loop_exit_advance(CPUNios2State *env,
 270                                             uintptr_t retaddr);
 271
 272 void do_nios2_semihosting(CPUNios2State *env);
 273
 274 #define CPU_RESOLVING_TYPE TYPE_NIOS2_CPU
 275
 276 #define cpu_gen_code cpu_nios2_gen_code
 277
 278 #define CPU_SAVE_VERSION 1
 279
 280 /* MMU modes definitions */
 281 #define MMU_SUPERVISOR_IDX  0
 282 #define MMU_USER_IDX        1
 283
 284 static inline int cpu_mmu_index(CPUNios2State *env, bool ifetch)
 285 {
 286     return (env->ctrl[CR_STATUS] & CR_STATUS_U) ? MMU_USER_IDX :
 287                                                   MMU_SUPERVISOR_IDX;
 288 }
 289
 290 #ifndef CONFIG_USER_ONLY
 291 bool nios2_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
 292                         MMUAccessType access_type, int mmu_idx,
 293                         bool probe, uintptr_t retaddr);
 294 #endif
 295
 296 typedef CPUNios2State CPUArchState;
 297 typedef Nios2CPU ArchCPU;
 298
 299 #include "exec/cpu-all.h"
 300
 301 FIELD(TBFLAGS, CRS0, 0, 1)  /* Set if CRS == 0. */
 302 FIELD(TBFLAGS, U, 1, 1)     /* Overlaps CR_STATUS_U */
 303 FIELD(TBFLAGS, R0_0, 2, 1)  /* Set if R0 == 0. */
 304
 305 static inline void cpu_get_tb_cpu_state(CPUNios2State *env, target_ulong *pc,
 306                                         target_ulong *cs_base, uint32_t *flags)
 307 {
 308     unsigned crs = FIELD_EX32(env->ctrl[CR_STATUS], CR_STATUS, CRS);
 309
 310     *pc = env->pc;
 311     *cs_base = 0;
 312     *flags = (env->ctrl[CR_STATUS] & CR_STATUS_U)
 313            | (crs ? 0 : R_TBFLAGS_CRS0_MASK)
 314            | (env->regs[0] ? 0 : R_TBFLAGS_R0_0_MASK);
 315 }
 316
 317 #endif /* NIOS2_CPU_H */