xref: /openbmc/qemu/target/m68k/cpu.h (revision 80adf54e)
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_FP_BSUN        48 /* Branch Set on Unordered */
59 #define EXCP_FP_INEX        49 /* Inexact result */
60 #define EXCP_FP_DZ          50 /* Divide by Zero */
61 #define EXCP_FP_UNFL        51 /* Underflow */
62 #define EXCP_FP_OPERR       52 /* Operand Error */
63 #define EXCP_FP_OVFL        53 /* Overflow */
64 #define EXCP_FP_SNAN        54 /* Signaling Not-A-Number */
65 #define EXCP_FP_UNIMP       55 /* Unimplemented Data type */
66 #define EXCP_UNSUPPORTED    61
67 
68 #define EXCP_RTE            0x100
69 #define EXCP_HALT_INSN      0x101
70 
71 #define NB_MMU_MODES 2
72 #define TARGET_INSN_START_EXTRA_WORDS 1
73 
74 typedef CPU_LDoubleU FPReg;
75 
76 typedef struct CPUM68KState {
77     uint32_t dregs[8];
78     uint32_t aregs[8];
79     uint32_t pc;
80     uint32_t sr;
81 
82     /* SSP and USP.  The current_sp is stored in aregs[7], the other here.  */
83     int current_sp;
84     uint32_t sp[2];
85 
86     /* Condition flags.  */
87     uint32_t cc_op;
88     uint32_t cc_x; /* always 0/1 */
89     uint32_t cc_n; /* in bit 31 (i.e. negative) */
90     uint32_t cc_v; /* in bit 31, unused, or computed from cc_n and cc_v */
91     uint32_t cc_c; /* either 0/1, unused, or computed from cc_n and cc_v */
92     uint32_t cc_z; /* == 0 or unused */
93 
94     FPReg fregs[8];
95     FPReg fp_result;
96     uint32_t fpcr;
97     uint32_t fpsr;
98     float_status fp_status;
99 
100     uint64_t mactmp;
101     /* EMAC Hardware deals with 48-bit values composed of one 32-bit and
102        two 8-bit parts.  We store a single 64-bit value and
103        rearrange/extend this when changing modes.  */
104     uint64_t macc[4];
105     uint32_t macsr;
106     uint32_t mac_mask;
107 
108     /* MMU status.  */
109     struct {
110         uint32_t ar;
111     } mmu;
112 
113     /* Control registers.  */
114     uint32_t vbr;
115     uint32_t mbar;
116     uint32_t rambar0;
117     uint32_t cacr;
118 
119     int pending_vector;
120     int pending_level;
121 
122     uint32_t qregs[MAX_QREGS];
123 
124     /* Fields up to this point are cleared by a CPU reset */
125     struct {} end_reset_fields;
126 
127     CPU_COMMON
128 
129     /* Fields from here on are preserved across CPU reset. */
130     uint32_t features;
131 } CPUM68KState;
132 
133 /**
134  * M68kCPU:
135  * @env: #CPUM68KState
136  *
137  * A Motorola 68k CPU.
138  */
139 struct M68kCPU {
140     /*< private >*/
141     CPUState parent_obj;
142     /*< public >*/
143 
144     CPUM68KState env;
145 };
146 
147 static inline M68kCPU *m68k_env_get_cpu(CPUM68KState *env)
148 {
149     return container_of(env, M68kCPU, env);
150 }
151 
152 #define ENV_GET_CPU(e) CPU(m68k_env_get_cpu(e))
153 
154 #define ENV_OFFSET offsetof(M68kCPU, env)
155 
156 void m68k_cpu_do_interrupt(CPUState *cpu);
157 bool m68k_cpu_exec_interrupt(CPUState *cpu, int int_req);
158 void m68k_cpu_dump_state(CPUState *cpu, FILE *f, fprintf_function cpu_fprintf,
159                          int flags);
160 hwaddr m68k_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
161 int m68k_cpu_gdb_read_register(CPUState *cpu, uint8_t *buf, int reg);
162 int m68k_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
163 
164 void m68k_tcg_init(void);
165 void m68k_cpu_init_gdb(M68kCPU *cpu);
166 M68kCPU *cpu_m68k_init(const char *cpu_model);
167 /* you can call this signal handler from your SIGBUS and SIGSEGV
168    signal handlers to inform the virtual CPU of exceptions. non zero
169    is returned if the signal was handled by the virtual CPU.  */
170 int cpu_m68k_signal_handler(int host_signum, void *pinfo,
171                            void *puc);
172 uint32_t cpu_m68k_get_ccr(CPUM68KState *env);
173 void cpu_m68k_set_ccr(CPUM68KState *env, uint32_t);
174 void cpu_m68k_set_fpcr(CPUM68KState *env, uint32_t val);
175 
176 
177 /* Instead of computing the condition codes after each m68k instruction,
178  * QEMU just stores one operand (called CC_SRC), the result
179  * (called CC_DEST) and the type of operation (called CC_OP). When the
180  * condition codes are needed, the condition codes can be calculated
181  * using this information. Condition codes are not generated if they
182  * are only needed for conditional branches.
183  */
184 typedef enum {
185     /* Translator only -- use env->cc_op.  */
186     CC_OP_DYNAMIC = -1,
187 
188     /* Each flag bit computed into cc_[xcnvz].  */
189     CC_OP_FLAGS,
190 
191     /* X in cc_x, C = X, N in cc_n, Z in cc_n, V via cc_n/cc_v.  */
192     CC_OP_ADDB, CC_OP_ADDW, CC_OP_ADDL,
193     CC_OP_SUBB, CC_OP_SUBW, CC_OP_SUBL,
194 
195     /* X in cc_x, {N,Z,C,V} via cc_n/cc_v.  */
196     CC_OP_CMPB, CC_OP_CMPW, CC_OP_CMPL,
197 
198     /* X in cc_x, C = 0, V = 0, N in cc_n, Z in cc_n.  */
199     CC_OP_LOGIC,
200 
201     CC_OP_NB
202 } CCOp;
203 
204 #define CCF_C 0x01
205 #define CCF_V 0x02
206 #define CCF_Z 0x04
207 #define CCF_N 0x08
208 #define CCF_X 0x10
209 
210 #define SR_I_SHIFT 8
211 #define SR_I  0x0700
212 #define SR_M  0x1000
213 #define SR_S  0x2000
214 #define SR_T  0x8000
215 
216 #define M68K_SSP    0
217 #define M68K_USP    1
218 
219 #define M68K_FPIAR_SHIFT  0
220 #define M68K_FPIAR        (1 << M68K_FPIAR_SHIFT)
221 #define M68K_FPSR_SHIFT   1
222 #define M68K_FPSR         (1 << M68K_FPSR_SHIFT)
223 #define M68K_FPCR_SHIFT   2
224 #define M68K_FPCR         (1 << M68K_FPCR_SHIFT)
225 
226 /* Floating-Point Status Register */
227 
228 /* Condition Code */
229 #define FPSR_CC_MASK  0x0f000000
230 #define FPSR_CC_A     0x01000000 /* Not-A-Number */
231 #define FPSR_CC_I     0x02000000 /* Infinity */
232 #define FPSR_CC_Z     0x04000000 /* Zero */
233 #define FPSR_CC_N     0x08000000 /* Negative */
234 
235 /* Quotient */
236 
237 #define FPSR_QT_MASK  0x00ff0000
238 
239 /* Floating-Point Control Register */
240 /* Rounding mode */
241 #define FPCR_RND_MASK   0x0030
242 #define FPCR_RND_N      0x0000
243 #define FPCR_RND_Z      0x0010
244 #define FPCR_RND_M      0x0020
245 #define FPCR_RND_P      0x0030
246 
247 /* Rounding precision */
248 #define FPCR_PREC_MASK  0x00c0
249 #define FPCR_PREC_X     0x0000
250 #define FPCR_PREC_S     0x0040
251 #define FPCR_PREC_D     0x0080
252 #define FPCR_PREC_U     0x00c0
253 
254 #define FPCR_EXCP_MASK 0xff00
255 
256 /* CACR fields are implementation defined, but some bits are common.  */
257 #define M68K_CACR_EUSP  0x10
258 
259 #define MACSR_PAV0  0x100
260 #define MACSR_OMC   0x080
261 #define MACSR_SU    0x040
262 #define MACSR_FI    0x020
263 #define MACSR_RT    0x010
264 #define MACSR_N     0x008
265 #define MACSR_Z     0x004
266 #define MACSR_V     0x002
267 #define MACSR_EV    0x001
268 
269 void m68k_set_irq_level(M68kCPU *cpu, int level, uint8_t vector);
270 void m68k_switch_sp(CPUM68KState *env);
271 
272 void do_m68k_semihosting(CPUM68KState *env, int nr);
273 
274 /* There are 4 ColdFire core ISA revisions: A, A+, B and C.
275    Each feature covers the subset of instructions common to the
276    ISA revisions mentioned.  */
277 
278 enum m68k_features {
279     M68K_FEATURE_M68000,
280     M68K_FEATURE_CF_ISA_A,
281     M68K_FEATURE_CF_ISA_B, /* (ISA B or C).  */
282     M68K_FEATURE_CF_ISA_APLUSC, /* BIT/BITREV, FF1, STRLDSR (ISA A+ or C).  */
283     M68K_FEATURE_BRAL, /* Long unconditional branch.  (ISA A+ or B).  */
284     M68K_FEATURE_CF_FPU,
285     M68K_FEATURE_CF_MAC,
286     M68K_FEATURE_CF_EMAC,
287     M68K_FEATURE_CF_EMAC_B, /* Revision B EMAC (dual accumulate).  */
288     M68K_FEATURE_USP, /* User Stack Pointer.  (ISA A+, B or C).  */
289     M68K_FEATURE_EXT_FULL, /* 68020+ full extension word.  */
290     M68K_FEATURE_WORD_INDEX, /* word sized address index registers.  */
291     M68K_FEATURE_SCALED_INDEX, /* scaled address index registers.  */
292     M68K_FEATURE_LONG_MULDIV, /* 32 bit multiply/divide. */
293     M68K_FEATURE_QUAD_MULDIV, /* 64 bit multiply/divide. */
294     M68K_FEATURE_BCCL, /* Long conditional branches.  */
295     M68K_FEATURE_BITFIELD, /* Bit field insns.  */
296     M68K_FEATURE_FPU,
297     M68K_FEATURE_CAS,
298     M68K_FEATURE_BKPT,
299     M68K_FEATURE_RTD,
300 };
301 
302 static inline int m68k_feature(CPUM68KState *env, int feature)
303 {
304     return (env->features & (1u << feature)) != 0;
305 }
306 
307 void m68k_cpu_list(FILE *f, fprintf_function cpu_fprintf);
308 
309 void register_m68k_insns (CPUM68KState *env);
310 
311 #ifdef CONFIG_USER_ONLY
312 /* Coldfire Linux uses 8k pages
313  * and m68k linux uses 4k pages
314  * use the smaller one
315  */
316 #define TARGET_PAGE_BITS 12
317 #else
318 /* Smallest TLB entry size is 1k.  */
319 #define TARGET_PAGE_BITS 10
320 #endif
321 
322 #define TARGET_PHYS_ADDR_SPACE_BITS 32
323 #define TARGET_VIRT_ADDR_SPACE_BITS 32
324 
325 #define cpu_init(cpu_model) CPU(cpu_m68k_init(cpu_model))
326 
327 #define cpu_signal_handler cpu_m68k_signal_handler
328 #define cpu_list m68k_cpu_list
329 
330 /* MMU modes definitions */
331 #define MMU_MODE0_SUFFIX _kernel
332 #define MMU_MODE1_SUFFIX _user
333 #define MMU_USER_IDX 1
334 static inline int cpu_mmu_index (CPUM68KState *env, bool ifetch)
335 {
336     return (env->sr & SR_S) == 0 ? 1 : 0;
337 }
338 
339 int m68k_cpu_handle_mmu_fault(CPUState *cpu, vaddr address, int rw,
340                               int mmu_idx);
341 
342 #include "exec/cpu-all.h"
343 
344 static inline void cpu_get_tb_cpu_state(CPUM68KState *env, target_ulong *pc,
345                                         target_ulong *cs_base, uint32_t *flags)
346 {
347     *pc = env->pc;
348     *cs_base = 0;
349     *flags = (env->sr & SR_S)                   /* Bit  13 */
350             | ((env->macsr >> 4) & 0xf);        /* Bits 0-3 */
351 }
352 
353 #endif
354