xref: /openbmc/qemu/target/m68k/cpu.h (revision e5074b384792caf33b1115168740c9067bd82055)
1 /*
2  * m68k virtual CPU header
3  *
4  *  Copyright (c) 2005-2007 CodeSourcery
5  *  Written by Paul Brook
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  * 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 #ifndef M68K_CPU_H
22 #define M68K_CPU_H
23 
24 #define TARGET_LONG_BITS 32
25 
26 #define CPUArchState struct CPUM68KState
27 
28 #include "qemu-common.h"
29 #include "exec/cpu-defs.h"
30 #include "cpu-qom.h"
31 #include "fpu/softfloat.h"
32 
33 #define OS_BYTE     0
34 #define OS_WORD     1
35 #define OS_LONG     2
36 #define OS_SINGLE   3
37 #define OS_DOUBLE   4
38 #define OS_EXTENDED 5
39 #define OS_PACKED   6
40 #define OS_UNSIZED  7
41 
42 #define MAX_QREGS 32
43 
44 #define EXCP_ACCESS         2   /* Access (MMU) error.  */
45 #define EXCP_ADDRESS        3   /* Address error.  */
46 #define EXCP_ILLEGAL        4   /* Illegal instruction.  */
47 #define EXCP_DIV0           5   /* Divide by zero */
48 #define EXCP_PRIVILEGE      8   /* Privilege violation.  */
49 #define EXCP_TRACE          9
50 #define EXCP_LINEA          10  /* Unimplemented line-A (MAC) opcode.  */
51 #define EXCP_LINEF          11  /* Unimplemented line-F (FPU) opcode.  */
52 #define EXCP_DEBUGNBP       12  /* Non-breakpoint debug interrupt.  */
53 #define EXCP_DEBEGBP        13  /* Breakpoint debug interrupt.  */
54 #define EXCP_FORMAT         14  /* RTE format error.  */
55 #define EXCP_UNINITIALIZED  15
56 #define EXCP_TRAP0          32   /* User trap #0.  */
57 #define EXCP_TRAP15         47   /* User trap #15.  */
58 #define EXCP_UNSUPPORTED    61
59 #define EXCP_ICE            13
60 
61 #define EXCP_RTE            0x100
62 #define EXCP_HALT_INSN      0x101
63 
64 #define NB_MMU_MODES 2
65 #define TARGET_INSN_START_EXTRA_WORDS 1
66 
67 typedef struct CPUM68KState {
68     uint32_t dregs[8];
69     uint32_t aregs[8];
70     uint32_t pc;
71     uint32_t sr;
72 
73     /* SSP and USP.  The current_sp is stored in aregs[7], the other here.  */
74     int current_sp;
75     uint32_t sp[2];
76 
77     /* Condition flags.  */
78     uint32_t cc_op;
79     uint32_t cc_x; /* always 0/1 */
80     uint32_t cc_n; /* in bit 31 (i.e. negative) */
81     uint32_t cc_v; /* in bit 31, unused, or computed from cc_n and cc_v */
82     uint32_t cc_c; /* either 0/1, unused, or computed from cc_n and cc_v */
83     uint32_t cc_z; /* == 0 or unused */
84 
85     float64 fregs[8];
86     float64 fp_result;
87     uint32_t fpcr;
88     uint32_t fpsr;
89     float_status fp_status;
90 
91     uint64_t mactmp;
92     /* EMAC Hardware deals with 48-bit values composed of one 32-bit and
93        two 8-bit parts.  We store a single 64-bit value and
94        rearrange/extend this when changing modes.  */
95     uint64_t macc[4];
96     uint32_t macsr;
97     uint32_t mac_mask;
98 
99     /* MMU status.  */
100     struct {
101         uint32_t ar;
102     } mmu;
103 
104     /* Control registers.  */
105     uint32_t vbr;
106     uint32_t mbar;
107     uint32_t rambar0;
108     uint32_t cacr;
109 
110     int pending_vector;
111     int pending_level;
112 
113     uint32_t qregs[MAX_QREGS];
114 
115     CPU_COMMON
116 
117     /* Fields from here on are preserved across CPU reset. */
118     uint32_t features;
119 } CPUM68KState;
120 
121 /**
122  * M68kCPU:
123  * @env: #CPUM68KState
124  *
125  * A Motorola 68k CPU.
126  */
127 struct M68kCPU {
128     /*< private >*/
129     CPUState parent_obj;
130     /*< public >*/
131 
132     CPUM68KState env;
133 };
134 
135 static inline M68kCPU *m68k_env_get_cpu(CPUM68KState *env)
136 {
137     return container_of(env, M68kCPU, env);
138 }
139 
140 #define ENV_GET_CPU(e) CPU(m68k_env_get_cpu(e))
141 
142 #define ENV_OFFSET offsetof(M68kCPU, env)
143 
144 void m68k_cpu_do_interrupt(CPUState *cpu);
145 bool m68k_cpu_exec_interrupt(CPUState *cpu, int int_req);
146 void m68k_cpu_dump_state(CPUState *cpu, FILE *f, fprintf_function cpu_fprintf,
147                          int flags);
148 hwaddr m68k_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
149 int m68k_cpu_gdb_read_register(CPUState *cpu, uint8_t *buf, int reg);
150 int m68k_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
151 
152 void m68k_tcg_init(void);
153 void m68k_cpu_init_gdb(M68kCPU *cpu);
154 M68kCPU *cpu_m68k_init(const char *cpu_model);
155 /* you can call this signal handler from your SIGBUS and SIGSEGV
156    signal handlers to inform the virtual CPU of exceptions. non zero
157    is returned if the signal was handled by the virtual CPU.  */
158 int cpu_m68k_signal_handler(int host_signum, void *pinfo,
159                            void *puc);
160 uint32_t cpu_m68k_get_ccr(CPUM68KState *env);
161 void cpu_m68k_set_ccr(CPUM68KState *env, uint32_t);
162 
163 
164 /* Instead of computing the condition codes after each m68k instruction,
165  * QEMU just stores one operand (called CC_SRC), the result
166  * (called CC_DEST) and the type of operation (called CC_OP). When the
167  * condition codes are needed, the condition codes can be calculated
168  * using this information. Condition codes are not generated if they
169  * are only needed for conditional branches.
170  */
171 typedef enum {
172     /* Translator only -- use env->cc_op.  */
173     CC_OP_DYNAMIC = -1,
174 
175     /* Each flag bit computed into cc_[xcnvz].  */
176     CC_OP_FLAGS,
177 
178     /* X in cc_x, C = X, N in cc_n, Z in cc_n, V via cc_n/cc_v.  */
179     CC_OP_ADDB, CC_OP_ADDW, CC_OP_ADDL,
180     CC_OP_SUBB, CC_OP_SUBW, CC_OP_SUBL,
181 
182     /* X in cc_x, {N,Z,C,V} via cc_n/cc_v.  */
183     CC_OP_CMPB, CC_OP_CMPW, CC_OP_CMPL,
184 
185     /* X in cc_x, C = 0, V = 0, N in cc_n, Z in cc_n.  */
186     CC_OP_LOGIC,
187 
188     CC_OP_NB
189 } CCOp;
190 
191 #define CCF_C 0x01
192 #define CCF_V 0x02
193 #define CCF_Z 0x04
194 #define CCF_N 0x08
195 #define CCF_X 0x10
196 
197 #define SR_I_SHIFT 8
198 #define SR_I  0x0700
199 #define SR_M  0x1000
200 #define SR_S  0x2000
201 #define SR_T  0x8000
202 
203 #define M68K_SSP    0
204 #define M68K_USP    1
205 
206 /* CACR fields are implementation defined, but some bits are common.  */
207 #define M68K_CACR_EUSP  0x10
208 
209 #define MACSR_PAV0  0x100
210 #define MACSR_OMC   0x080
211 #define MACSR_SU    0x040
212 #define MACSR_FI    0x020
213 #define MACSR_RT    0x010
214 #define MACSR_N     0x008
215 #define MACSR_Z     0x004
216 #define MACSR_V     0x002
217 #define MACSR_EV    0x001
218 
219 void m68k_set_irq_level(M68kCPU *cpu, int level, uint8_t vector);
220 void m68k_switch_sp(CPUM68KState *env);
221 
222 #define M68K_FPCR_PREC (1 << 6)
223 
224 void do_m68k_semihosting(CPUM68KState *env, int nr);
225 
226 /* There are 4 ColdFire core ISA revisions: A, A+, B and C.
227    Each feature covers the subset of instructions common to the
228    ISA revisions mentioned.  */
229 
230 enum m68k_features {
231     M68K_FEATURE_M68000,
232     M68K_FEATURE_CF_ISA_A,
233     M68K_FEATURE_CF_ISA_B, /* (ISA B or C).  */
234     M68K_FEATURE_CF_ISA_APLUSC, /* BIT/BITREV, FF1, STRLDSR (ISA A+ or C).  */
235     M68K_FEATURE_BRAL, /* Long unconditional branch.  (ISA A+ or B).  */
236     M68K_FEATURE_CF_FPU,
237     M68K_FEATURE_CF_MAC,
238     M68K_FEATURE_CF_EMAC,
239     M68K_FEATURE_CF_EMAC_B, /* Revision B EMAC (dual accumulate).  */
240     M68K_FEATURE_USP, /* User Stack Pointer.  (ISA A+, B or C).  */
241     M68K_FEATURE_EXT_FULL, /* 68020+ full extension word.  */
242     M68K_FEATURE_WORD_INDEX, /* word sized address index registers.  */
243     M68K_FEATURE_SCALED_INDEX, /* scaled address index registers.  */
244     M68K_FEATURE_LONG_MULDIV, /* 32 bit multiply/divide. */
245     M68K_FEATURE_QUAD_MULDIV, /* 64 bit multiply/divide. */
246     M68K_FEATURE_BCCL, /* Long conditional branches.  */
247     M68K_FEATURE_BITFIELD, /* Bit field insns.  */
248     M68K_FEATURE_FPU,
249     M68K_FEATURE_CAS,
250     M68K_FEATURE_BKPT,
251 };
252 
253 static inline int m68k_feature(CPUM68KState *env, int feature)
254 {
255     return (env->features & (1u << feature)) != 0;
256 }
257 
258 void m68k_cpu_list(FILE *f, fprintf_function cpu_fprintf);
259 
260 void register_m68k_insns (CPUM68KState *env);
261 
262 #ifdef CONFIG_USER_ONLY
263 /* Coldfire Linux uses 8k pages
264  * and m68k linux uses 4k pages
265  * use the smaller one
266  */
267 #define TARGET_PAGE_BITS 12
268 #else
269 /* Smallest TLB entry size is 1k.  */
270 #define TARGET_PAGE_BITS 10
271 #endif
272 
273 #define TARGET_PHYS_ADDR_SPACE_BITS 32
274 #define TARGET_VIRT_ADDR_SPACE_BITS 32
275 
276 #define cpu_init(cpu_model) CPU(cpu_m68k_init(cpu_model))
277 
278 #define cpu_signal_handler cpu_m68k_signal_handler
279 #define cpu_list m68k_cpu_list
280 
281 /* MMU modes definitions */
282 #define MMU_MODE0_SUFFIX _kernel
283 #define MMU_MODE1_SUFFIX _user
284 #define MMU_USER_IDX 1
285 static inline int cpu_mmu_index (CPUM68KState *env, bool ifetch)
286 {
287     return (env->sr & SR_S) == 0 ? 1 : 0;
288 }
289 
290 int m68k_cpu_handle_mmu_fault(CPUState *cpu, vaddr address, int rw,
291                               int mmu_idx);
292 
293 #include "exec/cpu-all.h"
294 
295 static inline void cpu_get_tb_cpu_state(CPUM68KState *env, target_ulong *pc,
296                                         target_ulong *cs_base, uint32_t *flags)
297 {
298     *pc = env->pc;
299     *cs_base = 0;
300     *flags = (env->fpcr & M68K_FPCR_PREC)       /* Bit  6 */
301             | (env->sr & SR_S)                  /* Bit  13 */
302             | ((env->macsr >> 4) & 0xf);        /* Bits 0-3 */
303 }
304 
305 #endif
306