xref: /qemu/target/avr/cpu.h (revision 8be545ba5a315a9aaf7307f143a4a7926a6e605c)
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 #include "system/memory.h"
27 
28 #ifdef CONFIG_USER_ONLY
29 #error "AVR 8-bit does not support user mode"
30 #endif
31 
32 #define CPU_RESOLVING_TYPE TYPE_AVR_CPU
33 
34 /*
35  * AVR has two memory spaces, data & code.
36  * e.g. both have 0 address
37  * ST/LD instructions access data space
38  * LPM/SPM and instruction fetching access code memory space
39  */
40 #define MMU_CODE_IDX 0
41 #define MMU_DATA_IDX 1
42 
43 #define EXCP_RESET 1
44 #define EXCP_INT(n) (EXCP_RESET + (n) + 1)
45 
46 /* Number of CPU registers */
47 #define NUMBER_OF_CPU_REGISTERS 32
48 
49 /* CPU registers mapped into i/o ports 0x38-0x3f. */
50 #define REG_38_RAMPD  0
51 #define REG_38_RAMPX  1
52 #define REG_38_RAMPY  2
53 #define REG_38_RAMPZ  3
54 #define REG_38_EIDN   4
55 #define REG_38_SPL    5
56 #define REG_38_SPH    6
57 #define REG_38_SREG   7
58 
59 /*
60  * Offsets of AVR memory regions in host memory space.
61  *
62  * This is needed because the AVR has separate code and data address
63  * spaces that both have start from zero but have to go somewhere in
64  * host memory.
65  *
66  * It's also useful to know where some things are, like the IO registers.
67  */
68 /* Flash program memory */
69 #define OFFSET_CODE 0x00000000
70 /* CPU registers, IO registers, and SRAM */
71 #define OFFSET_DATA 0x00800000
72 /*
73  * IO registers, including status register, stack pointer, and memory
74  * mapped peripherals, mapped just after CPU registers
75  */
76 #define OFFSET_IO_REGISTERS (OFFSET_DATA + NUMBER_OF_CPU_REGISTERS)
77 
78 typedef enum AVRFeature {
79     AVR_FEATURE_SRAM,
80 
81     AVR_FEATURE_1_BYTE_PC,
82     AVR_FEATURE_2_BYTE_PC,
83     AVR_FEATURE_3_BYTE_PC,
84 
85     AVR_FEATURE_1_BYTE_SP,
86     AVR_FEATURE_2_BYTE_SP,
87 
88     AVR_FEATURE_BREAK,
89     AVR_FEATURE_DES,
90     AVR_FEATURE_RMW, /* Read Modify Write - XCH LAC LAS LAT */
91 
92     AVR_FEATURE_EIJMP_EICALL,
93     AVR_FEATURE_IJMP_ICALL,
94     AVR_FEATURE_JMP_CALL,
95 
96     AVR_FEATURE_ADIW_SBIW,
97 
98     AVR_FEATURE_SPM,
99     AVR_FEATURE_SPMX,
100 
101     AVR_FEATURE_ELPMX,
102     AVR_FEATURE_ELPM,
103     AVR_FEATURE_LPMX,
104     AVR_FEATURE_LPM,
105 
106     AVR_FEATURE_MOVW,
107     AVR_FEATURE_MUL,
108     AVR_FEATURE_RAMPD,
109     AVR_FEATURE_RAMPX,
110     AVR_FEATURE_RAMPY,
111     AVR_FEATURE_RAMPZ,
112 } AVRFeature;
113 
114 typedef struct CPUArchState {
115     uint32_t pc_w; /* 0x003fffff up to 22 bits */
116 
117     uint32_t sregC; /* 0x00000001 1 bit */
118     uint32_t sregZ; /* 0x00000001 1 bit */
119     uint32_t sregN; /* 0x00000001 1 bit */
120     uint32_t sregV; /* 0x00000001 1 bit */
121     uint32_t sregS; /* 0x00000001 1 bit */
122     uint32_t sregH; /* 0x00000001 1 bit */
123     uint32_t sregT; /* 0x00000001 1 bit */
124     uint32_t sregI; /* 0x00000001 1 bit */
125 
126     uint32_t rampD; /* 0x00ff0000 8 bits */
127     uint32_t rampX; /* 0x00ff0000 8 bits */
128     uint32_t rampY; /* 0x00ff0000 8 bits */
129     uint32_t rampZ; /* 0x00ff0000 8 bits */
130     uint32_t eind; /* 0x00ff0000 8 bits */
131 
132     uint32_t r[NUMBER_OF_CPU_REGISTERS]; /* 8 bits each */
133     uint32_t sp; /* 16 bits */
134 
135     uint32_t skip; /* if set skip instruction */
136 
137     uint64_t intsrc; /* interrupt sources */
138     bool fullacc; /* CPU/MEM if true MEM only otherwise */
139 
140     uint64_t features;
141 } CPUAVRState;
142 
143 /**
144  *  AVRCPU:
145  *  @env: #CPUAVRState
146  *
147  *  A AVR CPU.
148  */
149 struct ArchCPU {
150     CPUState parent_obj;
151 
152     CPUAVRState env;
153 
154     MemoryRegion cpu_reg1;
155     MemoryRegion cpu_reg2;
156 
157     /* Initial value of stack pointer */
158     uint32_t init_sp;
159 };
160 
161 /**
162  *  AVRCPUClass:
163  *  @parent_realize: The parent class' realize handler.
164  *  @parent_phases: The parent class' reset phase handlers.
165  *
166  *  A AVR CPU model.
167  */
168 struct AVRCPUClass {
169     CPUClass parent_class;
170 
171     DeviceRealize parent_realize;
172     ResettablePhases parent_phases;
173 };
174 
175 extern const struct VMStateDescription vms_avr_cpu;
176 
177 void avr_cpu_do_interrupt(CPUState *cpu);
178 bool avr_cpu_exec_interrupt(CPUState *cpu, int int_req);
179 hwaddr avr_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
180 int avr_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
181 int avr_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
182 int avr_print_insn(bfd_vma addr, disassemble_info *info);
183 vaddr avr_cpu_gdb_adjust_breakpoint(CPUState *cpu, vaddr addr);
184 
185 static inline int avr_feature(CPUAVRState *env, AVRFeature feature)
186 {
187     return (env->features & (1U << feature)) != 0;
188 }
189 
190 static inline void set_avr_feature(CPUAVRState *env, int feature)
191 {
192     env->features |= (1U << feature);
193 }
194 
195 void avr_cpu_tcg_init(void);
196 void avr_cpu_translate_code(CPUState *cs, TranslationBlock *tb,
197                             int *max_insns, vaddr pc, void *host_pc);
198 
199 int cpu_avr_exec(CPUState *cpu);
200 
201 enum {
202     TB_FLAGS_FULL_ACCESS = 1,
203     TB_FLAGS_SKIP = 2,
204 };
205 
206 static inline void cpu_get_tb_cpu_state(CPUAVRState *env, vaddr *pc,
207                                         uint64_t *cs_base, uint32_t *pflags)
208 {
209     uint32_t flags = 0;
210 
211     *pc = env->pc_w * 2;
212     *cs_base = 0;
213 
214     if (env->fullacc) {
215         flags |= TB_FLAGS_FULL_ACCESS;
216     }
217     if (env->skip) {
218         flags |= TB_FLAGS_SKIP;
219     }
220 
221     *pflags = flags;
222 }
223 
224 static inline int cpu_interrupts_enabled(CPUAVRState *env)
225 {
226     return env->sregI != 0;
227 }
228 
229 static inline uint8_t cpu_get_sreg(CPUAVRState *env)
230 {
231     return (env->sregC) << 0
232          | (env->sregZ) << 1
233          | (env->sregN) << 2
234          | (env->sregV) << 3
235          | (env->sregS) << 4
236          | (env->sregH) << 5
237          | (env->sregT) << 6
238          | (env->sregI) << 7;
239 }
240 
241 static inline void cpu_set_sreg(CPUAVRState *env, uint8_t sreg)
242 {
243     env->sregC = (sreg >> 0) & 0x01;
244     env->sregZ = (sreg >> 1) & 0x01;
245     env->sregN = (sreg >> 2) & 0x01;
246     env->sregV = (sreg >> 3) & 0x01;
247     env->sregS = (sreg >> 4) & 0x01;
248     env->sregH = (sreg >> 5) & 0x01;
249     env->sregT = (sreg >> 6) & 0x01;
250     env->sregI = (sreg >> 7) & 0x01;
251 }
252 
253 bool avr_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
254                       MMUAccessType access_type, int mmu_idx,
255                       bool probe, uintptr_t retaddr);
256 
257 extern const MemoryRegionOps avr_cpu_reg1;
258 extern const MemoryRegionOps avr_cpu_reg2;
259 
260 #include "exec/cpu-all.h"
261 
262 #endif /* QEMU_AVR_CPU_H */
263