xref: /openbmc/qemu/target/m68k/cpu.h (revision fcf5ef2a)
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     /* Temporary storage for DIV helpers.  */
99     uint32_t div1;
100     uint32_t div2;
101 
102     /* MMU status.  */
103     struct {
104         uint32_t ar;
105     } mmu;
106 
107     /* Control registers.  */
108     uint32_t vbr;
109     uint32_t mbar;
110     uint32_t rambar0;
111     uint32_t cacr;
112 
113     int pending_vector;
114     int pending_level;
115 
116     uint32_t qregs[MAX_QREGS];
117 
118     CPU_COMMON
119 
120     /* Fields from here on are preserved across CPU reset. */
121     uint32_t features;
122 } CPUM68KState;
123 
124 /**
125  * M68kCPU:
126  * @env: #CPUM68KState
127  *
128  * A Motorola 68k CPU.
129  */
130 struct M68kCPU {
131     /*< private >*/
132     CPUState parent_obj;
133     /*< public >*/
134 
135     CPUM68KState env;
136 };
137 
138 static inline M68kCPU *m68k_env_get_cpu(CPUM68KState *env)
139 {
140     return container_of(env, M68kCPU, env);
141 }
142 
143 #define ENV_GET_CPU(e) CPU(m68k_env_get_cpu(e))
144 
145 #define ENV_OFFSET offsetof(M68kCPU, env)
146 
147 void m68k_cpu_do_interrupt(CPUState *cpu);
148 bool m68k_cpu_exec_interrupt(CPUState *cpu, int int_req);
149 void m68k_cpu_dump_state(CPUState *cpu, FILE *f, fprintf_function cpu_fprintf,
150                          int flags);
151 hwaddr m68k_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
152 int m68k_cpu_gdb_read_register(CPUState *cpu, uint8_t *buf, int reg);
153 int m68k_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
154 
155 void m68k_tcg_init(void);
156 void m68k_cpu_init_gdb(M68kCPU *cpu);
157 M68kCPU *cpu_m68k_init(const char *cpu_model);
158 /* you can call this signal handler from your SIGBUS and SIGSEGV
159    signal handlers to inform the virtual CPU of exceptions. non zero
160    is returned if the signal was handled by the virtual CPU.  */
161 int cpu_m68k_signal_handler(int host_signum, void *pinfo,
162                            void *puc);
163 uint32_t cpu_m68k_get_ccr(CPUM68KState *env);
164 void cpu_m68k_set_ccr(CPUM68KState *env, uint32_t);
165 
166 
167 /* Instead of computing the condition codes after each m68k instruction,
168  * QEMU just stores one operand (called CC_SRC), the result
169  * (called CC_DEST) and the type of operation (called CC_OP). When the
170  * condition codes are needed, the condition codes can be calculated
171  * using this information. Condition codes are not generated if they
172  * are only needed for conditional branches.
173  */
174 typedef enum {
175     /* Translator only -- use env->cc_op.  */
176     CC_OP_DYNAMIC = -1,
177 
178     /* Each flag bit computed into cc_[xcnvz].  */
179     CC_OP_FLAGS,
180 
181     /* X in cc_x, C = X, N in cc_n, Z in cc_n, V via cc_n/cc_v.  */
182     CC_OP_ADDB, CC_OP_ADDW, CC_OP_ADDL,
183     CC_OP_SUBB, CC_OP_SUBW, CC_OP_SUBL,
184 
185     /* X in cc_x, {N,Z,C,V} via cc_n/cc_v.  */
186     CC_OP_CMPB, CC_OP_CMPW, CC_OP_CMPL,
187 
188     /* X in cc_x, C = 0, V = 0, N in cc_n, Z in cc_n.  */
189     CC_OP_LOGIC,
190 
191     CC_OP_NB
192 } CCOp;
193 
194 #define CCF_C 0x01
195 #define CCF_V 0x02
196 #define CCF_Z 0x04
197 #define CCF_N 0x08
198 #define CCF_X 0x10
199 
200 #define SR_I_SHIFT 8
201 #define SR_I  0x0700
202 #define SR_M  0x1000
203 #define SR_S  0x2000
204 #define SR_T  0x8000
205 
206 #define M68K_SSP    0
207 #define M68K_USP    1
208 
209 /* CACR fields are implementation defined, but some bits are common.  */
210 #define M68K_CACR_EUSP  0x10
211 
212 #define MACSR_PAV0  0x100
213 #define MACSR_OMC   0x080
214 #define MACSR_SU    0x040
215 #define MACSR_FI    0x020
216 #define MACSR_RT    0x010
217 #define MACSR_N     0x008
218 #define MACSR_Z     0x004
219 #define MACSR_V     0x002
220 #define MACSR_EV    0x001
221 
222 void m68k_set_irq_level(M68kCPU *cpu, int level, uint8_t vector);
223 void m68k_switch_sp(CPUM68KState *env);
224 
225 #define M68K_FPCR_PREC (1 << 6)
226 
227 void do_m68k_semihosting(CPUM68KState *env, int nr);
228 
229 /* There are 4 ColdFire core ISA revisions: A, A+, B and C.
230    Each feature covers the subset of instructions common to the
231    ISA revisions mentioned.  */
232 
233 enum m68k_features {
234     M68K_FEATURE_M68000,
235     M68K_FEATURE_CF_ISA_A,
236     M68K_FEATURE_CF_ISA_B, /* (ISA B or C).  */
237     M68K_FEATURE_CF_ISA_APLUSC, /* BIT/BITREV, FF1, STRLDSR (ISA A+ or C).  */
238     M68K_FEATURE_BRAL, /* Long unconditional branch.  (ISA A+ or B).  */
239     M68K_FEATURE_CF_FPU,
240     M68K_FEATURE_CF_MAC,
241     M68K_FEATURE_CF_EMAC,
242     M68K_FEATURE_CF_EMAC_B, /* Revision B EMAC (dual accumulate).  */
243     M68K_FEATURE_USP, /* User Stack Pointer.  (ISA A+, B or C).  */
244     M68K_FEATURE_EXT_FULL, /* 68020+ full extension word.  */
245     M68K_FEATURE_WORD_INDEX, /* word sized address index registers.  */
246     M68K_FEATURE_SCALED_INDEX, /* scaled address index registers.  */
247     M68K_FEATURE_LONG_MULDIV, /* 32 bit multiply/divide. */
248     M68K_FEATURE_QUAD_MULDIV, /* 64 bit multiply/divide. */
249     M68K_FEATURE_BCCL, /* Long conditional branches.  */
250     M68K_FEATURE_BITFIELD, /* Bit field insns.  */
251     M68K_FEATURE_FPU,
252     M68K_FEATURE_CAS,
253     M68K_FEATURE_BKPT,
254 };
255 
256 static inline int m68k_feature(CPUM68KState *env, int feature)
257 {
258     return (env->features & (1u << feature)) != 0;
259 }
260 
261 void m68k_cpu_list(FILE *f, fprintf_function cpu_fprintf);
262 
263 void register_m68k_insns (CPUM68KState *env);
264 
265 #ifdef CONFIG_USER_ONLY
266 /* Coldfire Linux uses 8k pages
267  * and m68k linux uses 4k pages
268  * use the smaller one
269  */
270 #define TARGET_PAGE_BITS 12
271 #else
272 /* Smallest TLB entry size is 1k.  */
273 #define TARGET_PAGE_BITS 10
274 #endif
275 
276 #define TARGET_PHYS_ADDR_SPACE_BITS 32
277 #define TARGET_VIRT_ADDR_SPACE_BITS 32
278 
279 #define cpu_init(cpu_model) CPU(cpu_m68k_init(cpu_model))
280 
281 #define cpu_signal_handler cpu_m68k_signal_handler
282 #define cpu_list m68k_cpu_list
283 
284 /* MMU modes definitions */
285 #define MMU_MODE0_SUFFIX _kernel
286 #define MMU_MODE1_SUFFIX _user
287 #define MMU_USER_IDX 1
288 static inline int cpu_mmu_index (CPUM68KState *env, bool ifetch)
289 {
290     return (env->sr & SR_S) == 0 ? 1 : 0;
291 }
292 
293 int m68k_cpu_handle_mmu_fault(CPUState *cpu, vaddr address, int rw,
294                               int mmu_idx);
295 
296 #include "exec/cpu-all.h"
297 
298 static inline void cpu_get_tb_cpu_state(CPUM68KState *env, target_ulong *pc,
299                                         target_ulong *cs_base, uint32_t *flags)
300 {
301     *pc = env->pc;
302     *cs_base = 0;
303     *flags = (env->fpcr & M68K_FPCR_PREC)       /* Bit  6 */
304             | (env->sr & SR_S)                  /* Bit  13 */
305             | ((env->macsr >> 4) & 0xf);        /* Bits 0-3 */
306 }
307 
308 #endif
309