xref: /openbmc/qemu/target/microblaze/gdbstub.c (revision 139c1837)
1 /*
2  * MicroBlaze gdb server stub
3  *
4  * Copyright (c) 2003-2005 Fabrice Bellard
5  * Copyright (c) 2013 SUSE LINUX Products GmbH
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  * Lesser 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 #include "qemu/osdep.h"
21 #include "cpu.h"
22 #include "exec/gdbstub.h"
23 
24 int mb_cpu_gdb_read_register(CPUState *cs, GByteArray *mem_buf, int n)
25 {
26     MicroBlazeCPU *cpu = MICROBLAZE_CPU(cs);
27     CPUMBState *env = &cpu->env;
28     /*
29      * GDB expects SREGs in the following order:
30      * PC, MSR, EAR, ESR, FSR, BTR, EDR, PID, ZPR, TLBX, TLBSX, TLBLO, TLBHI.
31      * They aren't stored in this order, so make a map.
32      * PID, ZPR, TLBx, TLBsx, TLBLO, and TLBHI aren't modeled, so we don't
33      * map them to anything and return a value of 0 instead.
34      */
35     static const uint8_t sreg_map[6] = {
36         SR_PC,
37         SR_MSR,
38         SR_EAR,
39         SR_ESR,
40         SR_FSR,
41         SR_BTR
42     };
43 
44     /*
45      * GDB expects registers to be reported in this order:
46      * R0-R31
47      * PC-BTR
48      * PVR0-PVR11
49      * EDR-TLBHI
50      * SLR-SHR
51      */
52     if (n < 32) {
53         return gdb_get_reg32(mem_buf, env->regs[n]);
54     } else {
55         n -= 32;
56         switch (n) {
57         case 0 ... 5:
58             return gdb_get_reg32(mem_buf, env->sregs[sreg_map[n]]);
59         /* PVR12 is intentionally skipped */
60         case 6 ... 17:
61             n -= 6;
62             return gdb_get_reg32(mem_buf, env->pvr.regs[n]);
63         case 18:
64             return gdb_get_reg32(mem_buf, env->sregs[SR_EDR]);
65         /* Other SRegs aren't modeled, so report a value of 0 */
66         case 19 ... 24:
67             return gdb_get_reg32(mem_buf, 0);
68         case 25:
69             return gdb_get_reg32(mem_buf, env->slr);
70         case 26:
71             return gdb_get_reg32(mem_buf, env->shr);
72         default:
73             return 0;
74         }
75     }
76 }
77 
78 int mb_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
79 {
80     MicroBlazeCPU *cpu = MICROBLAZE_CPU(cs);
81     CPUClass *cc = CPU_GET_CLASS(cs);
82     CPUMBState *env = &cpu->env;
83     uint32_t tmp;
84 
85     /*
86      * GDB expects SREGs in the following order:
87      * PC, MSR, EAR, ESR, FSR, BTR, EDR, PID, ZPR, TLBX, TLBSX, TLBLO, TLBHI.
88      * They aren't stored in this order, so make a map.
89      * PID, ZPR, TLBx, TLBsx, TLBLO, and TLBHI aren't modeled, so we don't
90      * map them to anything.
91      */
92     static const uint8_t sreg_map[6] = {
93         SR_PC,
94         SR_MSR,
95         SR_EAR,
96         SR_ESR,
97         SR_FSR,
98         SR_BTR
99     };
100 
101     if (n > cc->gdb_num_core_regs) {
102         return 0;
103     }
104 
105     tmp = ldl_p(mem_buf);
106 
107     /*
108      * GDB expects registers to be reported in this order:
109      * R0-R31
110      * PC-BTR
111      * PVR0-PVR11
112      * EDR-TLBHI
113      * SLR-SHR
114      */
115     if (n < 32) {
116         env->regs[n] = tmp;
117     } else {
118         n -= 32;
119         switch (n) {
120         case 0 ... 5:
121             env->sregs[sreg_map[n]] = tmp;
122             break;
123         /* PVR12 is intentionally skipped */
124         case 6 ... 17:
125             n -= 6;
126             env->pvr.regs[n] = tmp;
127             break;
128         /* Only EDR is modeled in these indeces, so ignore the rest */
129         case 18:
130             env->sregs[SR_EDR] = tmp;
131             break;
132         case 25:
133             env->slr = tmp;
134             break;
135         case 26:
136             env->shr = tmp;
137             break;
138         }
139     }
140     return 4;
141 }
142