target/avr/cpu.h

   1 /*
   2  * QEMU AVR CPU
   3  *
   4  * Copyright (c) 2016-2020 Michael Rolnik
   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 QEMU_AVR_CPU_H
  22 #define QEMU_AVR_CPU_H
  23
  24 #include "cpu-qom.h"
  25 #include "exec/cpu-defs.h"
  26
  27 #ifdef CONFIG_USER_ONLY
  28 #error "AVR 8-bit does not support user mode"
  29 #endif
  30
  31 #define CPU_RESOLVING_TYPE TYPE_AVR_CPU
  32
  33 #define TCG_GUEST_DEFAULT_MO 0
  34
  35 /*
  36  * AVR has two memory spaces, data & code.
  37  * e.g. both have 0 address
  38  * ST/LD instructions access data space
  39  * LPM/SPM and instruction fetching access code memory space
  40  */
  41 #define MMU_CODE_IDX 0
  42 #define MMU_DATA_IDX 1
  43
  44 #define EXCP_RESET 1
  45 #define EXCP_INT(n) (EXCP_RESET + (n) + 1)
  46
  47 /* Number of CPU registers */
  48 #define NUMBER_OF_CPU_REGISTERS 32
  49 /* Number of IO registers accessible by ld/st/in/out */
  50 #define NUMBER_OF_IO_REGISTERS 64
  51
  52 /*
  53  * Offsets of AVR memory regions in host memory space.
  54  *
  55  * This is needed because the AVR has separate code and data address
  56  * spaces that both have start from zero but have to go somewhere in
  57  * host memory.
  58  *
  59  * It's also useful to know where some things are, like the IO registers.
  60  */
  61 /* Flash program memory */
  62 #define OFFSET_CODE 0x00000000
  63 /* CPU registers, IO registers, and SRAM */
  64 #define OFFSET_DATA 0x00800000
  65 /* CPU registers specifically, these are mapped at the start of data */
  66 #define OFFSET_CPU_REGISTERS OFFSET_DATA
  67 /*
  68  * IO registers, including status register, stack pointer, and memory
  69  * mapped peripherals, mapped just after CPU registers
  70  */
  71 #define OFFSET_IO_REGISTERS (OFFSET_DATA + NUMBER_OF_CPU_REGISTERS)
  72
  73 typedef enum AVRFeature {
  74     AVR_FEATURE_SRAM,
  75
  76     AVR_FEATURE_1_BYTE_PC,
  77     AVR_FEATURE_2_BYTE_PC,
  78     AVR_FEATURE_3_BYTE_PC,
  79
  80     AVR_FEATURE_1_BYTE_SP,
  81     AVR_FEATURE_2_BYTE_SP,
  82
  83     AVR_FEATURE_BREAK,
  84     AVR_FEATURE_DES,
  85     AVR_FEATURE_RMW, /* Read Modify Write - XCH LAC LAS LAT */
  86
  87     AVR_FEATURE_EIJMP_EICALL,
  88     AVR_FEATURE_IJMP_ICALL,
  89     AVR_FEATURE_JMP_CALL,
  90
  91     AVR_FEATURE_ADIW_SBIW,
  92
  93     AVR_FEATURE_SPM,
  94     AVR_FEATURE_SPMX,
  95
  96     AVR_FEATURE_ELPMX,
  97     AVR_FEATURE_ELPM,
  98     AVR_FEATURE_LPMX,
  99     AVR_FEATURE_LPM,
 100
 101     AVR_FEATURE_MOVW,
 102     AVR_FEATURE_MUL,
 103     AVR_FEATURE_RAMPD,
 104     AVR_FEATURE_RAMPX,
 105     AVR_FEATURE_RAMPY,
 106     AVR_FEATURE_RAMPZ,
 107 } AVRFeature;
 108
 109 typedef struct CPUArchState {
 110     uint32_t pc_w; /* 0x003fffff up to 22 bits */
 111
 112     uint32_t sregC; /* 0x00000001 1 bit */
 113     uint32_t sregZ; /* 0x00000001 1 bit */
 114     uint32_t sregN; /* 0x00000001 1 bit */
 115     uint32_t sregV; /* 0x00000001 1 bit */
 116     uint32_t sregS; /* 0x00000001 1 bit */
 117     uint32_t sregH; /* 0x00000001 1 bit */
 118     uint32_t sregT; /* 0x00000001 1 bit */
 119     uint32_t sregI; /* 0x00000001 1 bit */
 120
 121     uint32_t rampD; /* 0x00ff0000 8 bits */
 122     uint32_t rampX; /* 0x00ff0000 8 bits */
 123     uint32_t rampY; /* 0x00ff0000 8 bits */
 124     uint32_t rampZ; /* 0x00ff0000 8 bits */
 125     uint32_t eind; /* 0x00ff0000 8 bits */
 126
 127     uint32_t r[NUMBER_OF_CPU_REGISTERS]; /* 8 bits each */
 128     uint32_t sp; /* 16 bits */
 129
 130     uint32_t skip; /* if set skip instruction */
 131
 132     uint64_t intsrc; /* interrupt sources */
 133     bool fullacc; /* CPU/MEM if true MEM only otherwise */
 134
 135     uint64_t features;
 136 } CPUAVRState;
 137
 138 /**
 139  *  AVRCPU:
 140  *  @env: #CPUAVRState
 141  *
 142  *  A AVR CPU.
 143  */
 144 struct ArchCPU {
 145     CPUState parent_obj;
 146
 147     CPUAVRState env;
 148
 149     /* Initial value of stack pointer */
 150     uint32_t init_sp;
 151 };
 152
 153 /**
 154  *  AVRCPUClass:
 155  *  @parent_realize: The parent class' realize handler.
 156  *  @parent_phases: The parent class' reset phase handlers.
 157  *
 158  *  A AVR CPU model.
 159  */
 160 struct AVRCPUClass {
 161     CPUClass parent_class;
 162
 163     DeviceRealize parent_realize;
 164     ResettablePhases parent_phases;
 165 };
 166
 167 extern const struct VMStateDescription vms_avr_cpu;
 168
 169 void avr_cpu_do_interrupt(CPUState *cpu);
 170 bool avr_cpu_exec_interrupt(CPUState *cpu, int int_req);
 171 hwaddr avr_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
 172 int avr_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
 173 int avr_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
 174 int avr_print_insn(bfd_vma addr, disassemble_info *info);
 175 vaddr avr_cpu_gdb_adjust_breakpoint(CPUState *cpu, vaddr addr);
 176
 177 static inline int avr_feature(CPUAVRState *env, AVRFeature feature)
 178 {
 179     return (env->features & (1U << feature)) != 0;
 180 }
 181
 182 static inline void set_avr_feature(CPUAVRState *env, int feature)
 183 {
 184     env->features |= (1U << feature);
 185 }
 186
 187 void avr_cpu_tcg_init(void);
 188
 189 int cpu_avr_exec(CPUState *cpu);
 190
 191 enum {
 192     TB_FLAGS_FULL_ACCESS = 1,
 193     TB_FLAGS_SKIP = 2,
 194 };
 195
 196 static inline void cpu_get_tb_cpu_state(CPUAVRState *env, vaddr *pc,
 197                                         uint64_t *cs_base, uint32_t *pflags)
 198 {
 199     uint32_t flags = 0;
 200
 201     *pc = env->pc_w * 2;
 202     *cs_base = 0;
 203
 204     if (env->fullacc) {
 205         flags |= TB_FLAGS_FULL_ACCESS;
 206     }
 207     if (env->skip) {
 208         flags |= TB_FLAGS_SKIP;
 209     }
 210
 211     *pflags = flags;
 212 }
 213
 214 static inline int cpu_interrupts_enabled(CPUAVRState *env)
 215 {
 216     return env->sregI != 0;
 217 }
 218
 219 static inline uint8_t cpu_get_sreg(CPUAVRState *env)
 220 {
 221     return (env->sregC) << 0
 222          | (env->sregZ) << 1
 223          | (env->sregN) << 2
 224          | (env->sregV) << 3
 225          | (env->sregS) << 4
 226          | (env->sregH) << 5
 227          | (env->sregT) << 6
 228          | (env->sregI) << 7;
 229 }
 230
 231 static inline void cpu_set_sreg(CPUAVRState *env, uint8_t sreg)
 232 {
 233     env->sregC = (sreg >> 0) & 0x01;
 234     env->sregZ = (sreg >> 1) & 0x01;
 235     env->sregN = (sreg >> 2) & 0x01;
 236     env->sregV = (sreg >> 3) & 0x01;
 237     env->sregS = (sreg >> 4) & 0x01;
 238     env->sregH = (sreg >> 5) & 0x01;
 239     env->sregT = (sreg >> 6) & 0x01;
 240     env->sregI = (sreg >> 7) & 0x01;
 241 }
 242
 243 bool avr_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
 244                       MMUAccessType access_type, int mmu_idx,
 245                       bool probe, uintptr_t retaddr);
 246
 247 #include "exec/cpu-all.h"
 248
 249 #endif /* QEMU_AVR_CPU_H */