xref: /openbmc/qemu/target/m68k/cpu.h (revision 08da3180)
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 
41 #define MAX_QREGS 32
42 
43 #define EXCP_ACCESS         2   /* Access (MMU) error.  */
44 #define EXCP_ADDRESS        3   /* Address error.  */
45 #define EXCP_ILLEGAL        4   /* Illegal instruction.  */
46 #define EXCP_DIV0           5   /* Divide by zero */
47 #define EXCP_PRIVILEGE      8   /* Privilege violation.  */
48 #define EXCP_TRACE          9
49 #define EXCP_LINEA          10  /* Unimplemented line-A (MAC) opcode.  */
50 #define EXCP_LINEF          11  /* Unimplemented line-F (FPU) opcode.  */
51 #define EXCP_DEBUGNBP       12  /* Non-breakpoint debug interrupt.  */
52 #define EXCP_DEBEGBP        13  /* Breakpoint debug interrupt.  */
53 #define EXCP_FORMAT         14  /* RTE format error.  */
54 #define EXCP_UNINITIALIZED  15
55 #define EXCP_TRAP0          32   /* User trap #0.  */
56 #define EXCP_TRAP15         47   /* User trap #15.  */
57 #define EXCP_UNSUPPORTED    61
58 #define EXCP_ICE            13
59 
60 #define EXCP_RTE            0x100
61 #define EXCP_HALT_INSN      0x101
62 
63 #define NB_MMU_MODES 2
64 #define TARGET_INSN_START_EXTRA_WORDS 1
65 
66 typedef struct CPUM68KState {
67     uint32_t dregs[8];
68     uint32_t aregs[8];
69     uint32_t pc;
70     uint32_t sr;
71 
72     /* SSP and USP.  The current_sp is stored in aregs[7], the other here.  */
73     int current_sp;
74     uint32_t sp[2];
75 
76     /* Condition flags.  */
77     uint32_t cc_op;
78     uint32_t cc_x; /* always 0/1 */
79     uint32_t cc_n; /* in bit 31 (i.e. negative) */
80     uint32_t cc_v; /* in bit 31, unused, or computed from cc_n and cc_v */
81     uint32_t cc_c; /* either 0/1, unused, or computed from cc_n and cc_v */
82     uint32_t cc_z; /* == 0 or unused */
83 
84     float64 fregs[8];
85     float64 fp_result;
86     uint32_t fpcr;
87     uint32_t fpsr;
88     float_status fp_status;
89 
90     uint64_t mactmp;
91     /* EMAC Hardware deals with 48-bit values composed of one 32-bit and
92        two 8-bit parts.  We store a single 64-bit value and
93        rearrange/extend this when changing modes.  */
94     uint64_t macc[4];
95     uint32_t macsr;
96     uint32_t mac_mask;
97 
98     /* MMU status.  */
99     struct {
100         uint32_t ar;
101     } mmu;
102 
103     /* Control registers.  */
104     uint32_t vbr;
105     uint32_t mbar;
106     uint32_t rambar0;
107     uint32_t cacr;
108 
109     int pending_vector;
110     int pending_level;
111 
112     uint32_t qregs[MAX_QREGS];
113 
114     CPU_COMMON
115 
116     /* Fields from here on are preserved across CPU reset. */
117     uint32_t features;
118 } CPUM68KState;
119 
120 /**
121  * M68kCPU:
122  * @env: #CPUM68KState
123  *
124  * A Motorola 68k CPU.
125  */
126 struct M68kCPU {
127     /*< private >*/
128     CPUState parent_obj;
129     /*< public >*/
130 
131     CPUM68KState env;
132 };
133 
134 static inline M68kCPU *m68k_env_get_cpu(CPUM68KState *env)
135 {
136     return container_of(env, M68kCPU, env);
137 }
138 
139 #define ENV_GET_CPU(e) CPU(m68k_env_get_cpu(e))
140 
141 #define ENV_OFFSET offsetof(M68kCPU, env)
142 
143 void m68k_cpu_do_interrupt(CPUState *cpu);
144 bool m68k_cpu_exec_interrupt(CPUState *cpu, int int_req);
145 void m68k_cpu_dump_state(CPUState *cpu, FILE *f, fprintf_function cpu_fprintf,
146                          int flags);
147 hwaddr m68k_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
148 int m68k_cpu_gdb_read_register(CPUState *cpu, uint8_t *buf, int reg);
149 int m68k_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
150 
151 void m68k_tcg_init(void);
152 void m68k_cpu_init_gdb(M68kCPU *cpu);
153 M68kCPU *cpu_m68k_init(const char *cpu_model);
154 /* you can call this signal handler from your SIGBUS and SIGSEGV
155    signal handlers to inform the virtual CPU of exceptions. non zero
156    is returned if the signal was handled by the virtual CPU.  */
157 int cpu_m68k_signal_handler(int host_signum, void *pinfo,
158                            void *puc);
159 uint32_t cpu_m68k_get_ccr(CPUM68KState *env);
160 void cpu_m68k_set_ccr(CPUM68KState *env, uint32_t);
161 
162 
163 /* Instead of computing the condition codes after each m68k instruction,
164  * QEMU just stores one operand (called CC_SRC), the result
165  * (called CC_DEST) and the type of operation (called CC_OP). When the
166  * condition codes are needed, the condition codes can be calculated
167  * using this information. Condition codes are not generated if they
168  * are only needed for conditional branches.
169  */
170 typedef enum {
171     /* Translator only -- use env->cc_op.  */
172     CC_OP_DYNAMIC = -1,
173 
174     /* Each flag bit computed into cc_[xcnvz].  */
175     CC_OP_FLAGS,
176 
177     /* X in cc_x, C = X, N in cc_n, Z in cc_n, V via cc_n/cc_v.  */
178     CC_OP_ADDB, CC_OP_ADDW, CC_OP_ADDL,
179     CC_OP_SUBB, CC_OP_SUBW, CC_OP_SUBL,
180 
181     /* X in cc_x, {N,Z,C,V} via cc_n/cc_v.  */
182     CC_OP_CMPB, CC_OP_CMPW, CC_OP_CMPL,
183 
184     /* X in cc_x, C = 0, V = 0, N in cc_n, Z in cc_n.  */
185     CC_OP_LOGIC,
186 
187     CC_OP_NB
188 } CCOp;
189 
190 #define CCF_C 0x01
191 #define CCF_V 0x02
192 #define CCF_Z 0x04
193 #define CCF_N 0x08
194 #define CCF_X 0x10
195 
196 #define SR_I_SHIFT 8
197 #define SR_I  0x0700
198 #define SR_M  0x1000
199 #define SR_S  0x2000
200 #define SR_T  0x8000
201 
202 #define M68K_SSP    0
203 #define M68K_USP    1
204 
205 /* CACR fields are implementation defined, but some bits are common.  */
206 #define M68K_CACR_EUSP  0x10
207 
208 #define MACSR_PAV0  0x100
209 #define MACSR_OMC   0x080
210 #define MACSR_SU    0x040
211 #define MACSR_FI    0x020
212 #define MACSR_RT    0x010
213 #define MACSR_N     0x008
214 #define MACSR_Z     0x004
215 #define MACSR_V     0x002
216 #define MACSR_EV    0x001
217 
218 void m68k_set_irq_level(M68kCPU *cpu, int level, uint8_t vector);
219 void m68k_switch_sp(CPUM68KState *env);
220 
221 #define M68K_FPCR_PREC (1 << 6)
222 
223 void do_m68k_semihosting(CPUM68KState *env, int nr);
224 
225 /* There are 4 ColdFire core ISA revisions: A, A+, B and C.
226    Each feature covers the subset of instructions common to the
227    ISA revisions mentioned.  */
228 
229 enum m68k_features {
230     M68K_FEATURE_M68000,
231     M68K_FEATURE_CF_ISA_A,
232     M68K_FEATURE_CF_ISA_B, /* (ISA B or C).  */
233     M68K_FEATURE_CF_ISA_APLUSC, /* BIT/BITREV, FF1, STRLDSR (ISA A+ or C).  */
234     M68K_FEATURE_BRAL, /* Long unconditional branch.  (ISA A+ or B).  */
235     M68K_FEATURE_CF_FPU,
236     M68K_FEATURE_CF_MAC,
237     M68K_FEATURE_CF_EMAC,
238     M68K_FEATURE_CF_EMAC_B, /* Revision B EMAC (dual accumulate).  */
239     M68K_FEATURE_USP, /* User Stack Pointer.  (ISA A+, B or C).  */
240     M68K_FEATURE_EXT_FULL, /* 68020+ full extension word.  */
241     M68K_FEATURE_WORD_INDEX, /* word sized address index registers.  */
242     M68K_FEATURE_SCALED_INDEX, /* scaled address index registers.  */
243     M68K_FEATURE_LONG_MULDIV, /* 32 bit multiply/divide. */
244     M68K_FEATURE_QUAD_MULDIV, /* 64 bit multiply/divide. */
245     M68K_FEATURE_BCCL, /* Long conditional branches.  */
246     M68K_FEATURE_BITFIELD, /* Bit field insns.  */
247     M68K_FEATURE_FPU,
248     M68K_FEATURE_CAS,
249     M68K_FEATURE_BKPT,
250 };
251 
252 static inline int m68k_feature(CPUM68KState *env, int feature)
253 {
254     return (env->features & (1u << feature)) != 0;
255 }
256 
257 void m68k_cpu_list(FILE *f, fprintf_function cpu_fprintf);
258 
259 void register_m68k_insns (CPUM68KState *env);
260 
261 #ifdef CONFIG_USER_ONLY
262 /* Coldfire Linux uses 8k pages
263  * and m68k linux uses 4k pages
264  * use the smaller one
265  */
266 #define TARGET_PAGE_BITS 12
267 #else
268 /* Smallest TLB entry size is 1k.  */
269 #define TARGET_PAGE_BITS 10
270 #endif
271 
272 #define TARGET_PHYS_ADDR_SPACE_BITS 32
273 #define TARGET_VIRT_ADDR_SPACE_BITS 32
274 
275 #define cpu_init(cpu_model) CPU(cpu_m68k_init(cpu_model))
276 
277 #define cpu_signal_handler cpu_m68k_signal_handler
278 #define cpu_list m68k_cpu_list
279 
280 /* MMU modes definitions */
281 #define MMU_MODE0_SUFFIX _kernel
282 #define MMU_MODE1_SUFFIX _user
283 #define MMU_USER_IDX 1
284 static inline int cpu_mmu_index (CPUM68KState *env, bool ifetch)
285 {
286     return (env->sr & SR_S) == 0 ? 1 : 0;
287 }
288 
289 int m68k_cpu_handle_mmu_fault(CPUState *cpu, vaddr address, int rw,
290                               int mmu_idx);
291 
292 #include "exec/cpu-all.h"
293 
294 static inline void cpu_get_tb_cpu_state(CPUM68KState *env, target_ulong *pc,
295                                         target_ulong *cs_base, uint32_t *flags)
296 {
297     *pc = env->pc;
298     *cs_base = 0;
299     *flags = (env->fpcr & M68K_FPCR_PREC)       /* Bit  6 */
300             | (env->sr & SR_S)                  /* Bit  13 */
301             | ((env->macsr >> 4) & 0xf);        /* Bits 0-3 */
302 }
303 
304 #endif
305