xref: /openbmc/qemu/target/xtensa/dbg_helper.c (revision 2df1eb27)
1 /*
2  * Copyright (c) 2011 - 2019, Max Filippov, Open Source and Linux Lab.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions are met:
7  *     * Redistributions of source code must retain the above copyright
8  *       notice, this list of conditions and the following disclaimer.
9  *     * Redistributions in binary form must reproduce the above copyright
10  *       notice, this list of conditions and the following disclaimer in the
11  *       documentation and/or other materials provided with the distribution.
12  *     * Neither the name of the Open Source and Linux Lab nor the
13  *       names of its contributors may be used to endorse or promote products
14  *       derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
20  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
23  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
25  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include "qemu/osdep.h"
29 #include "qemu/log.h"
30 #include "cpu.h"
31 #include "exec/helper-proto.h"
32 #include "qemu/host-utils.h"
33 #include "exec/exec-all.h"
34 #include "exec/address-spaces.h"
35 
36 void HELPER(wsr_ibreakenable)(CPUXtensaState *env, uint32_t v)
37 {
38     CPUState *cs = env_cpu(env);
39     uint32_t change = v ^ env->sregs[IBREAKENABLE];
40     unsigned i;
41 
42     for (i = 0; i < env->config->nibreak; ++i) {
43         if (change & (1 << i)) {
44             if (v & (1 << i)) {
45                 cpu_breakpoint_insert(cs, env->sregs[IBREAKA + i],
46                                       BP_CPU, &env->cpu_breakpoint[i]);
47             } else {
48                 cpu_breakpoint_remove_by_ref(cs, env->cpu_breakpoint[i]);
49                 env->cpu_breakpoint[i] = NULL;
50             }
51         }
52     }
53     env->sregs[IBREAKENABLE] = v & ((1 << env->config->nibreak) - 1);
54 }
55 
56 void HELPER(wsr_ibreaka)(CPUXtensaState *env, uint32_t i, uint32_t v)
57 {
58     if (env->sregs[IBREAKENABLE] & (1 << i) && env->sregs[IBREAKA + i] != v) {
59         CPUState *cs = env_cpu(env);
60 
61         cpu_breakpoint_remove_by_ref(cs, env->cpu_breakpoint[i]);
62         cpu_breakpoint_insert(cs, v, BP_CPU, &env->cpu_breakpoint[i]);
63     }
64     env->sregs[IBREAKA + i] = v;
65 }
66 
67 bool xtensa_debug_check_breakpoint(CPUState *cs)
68 {
69     XtensaCPU *cpu = XTENSA_CPU(cs);
70     CPUXtensaState *env = &cpu->env;
71     unsigned int i;
72 
73     if (xtensa_get_cintlevel(env) >= env->config->debug_level) {
74         return false;
75     }
76     for (i = 0; i < env->config->nibreak; ++i) {
77         if (env->sregs[IBREAKENABLE] & (1 << i) &&
78             env->sregs[IBREAKA + i] == env->pc) {
79             return true;
80         }
81     }
82     return false;
83 }
84 
85 static void set_dbreak(CPUXtensaState *env, unsigned i, uint32_t dbreaka,
86         uint32_t dbreakc)
87 {
88     CPUState *cs = env_cpu(env);
89     int flags = BP_CPU | BP_STOP_BEFORE_ACCESS;
90     uint32_t mask = dbreakc | ~DBREAKC_MASK;
91 
92     if (env->cpu_watchpoint[i]) {
93         cpu_watchpoint_remove_by_ref(cs, env->cpu_watchpoint[i]);
94     }
95     if (dbreakc & DBREAKC_SB) {
96         flags |= BP_MEM_WRITE;
97     }
98     if (dbreakc & DBREAKC_LB) {
99         flags |= BP_MEM_READ;
100     }
101     /* contiguous mask after inversion is one less than some power of 2 */
102     if ((~mask + 1) & ~mask) {
103         qemu_log_mask(LOG_GUEST_ERROR,
104                       "DBREAKC mask is not contiguous: 0x%08x\n", dbreakc);
105         /* cut mask after the first zero bit */
106         mask = 0xffffffff << (32 - clo32(mask));
107     }
108     if (cpu_watchpoint_insert(cs, dbreaka & mask, ~mask + 1,
109                               flags, &env->cpu_watchpoint[i])) {
110         env->cpu_watchpoint[i] = NULL;
111         qemu_log_mask(LOG_GUEST_ERROR,
112                       "Failed to set data breakpoint at 0x%08x/%d\n",
113                       dbreaka & mask, ~mask + 1);
114     }
115 }
116 
117 void HELPER(wsr_dbreaka)(CPUXtensaState *env, uint32_t i, uint32_t v)
118 {
119     uint32_t dbreakc = env->sregs[DBREAKC + i];
120 
121     if ((dbreakc & DBREAKC_SB_LB) &&
122         env->sregs[DBREAKA + i] != v) {
123         set_dbreak(env, i, v, dbreakc);
124     }
125     env->sregs[DBREAKA + i] = v;
126 }
127 
128 void HELPER(wsr_dbreakc)(CPUXtensaState *env, uint32_t i, uint32_t v)
129 {
130     if ((env->sregs[DBREAKC + i] ^ v) & (DBREAKC_SB_LB | DBREAKC_MASK)) {
131         if (v & DBREAKC_SB_LB) {
132             set_dbreak(env, i, env->sregs[DBREAKA + i], v);
133         } else {
134             if (env->cpu_watchpoint[i]) {
135                 CPUState *cs = env_cpu(env);
136 
137                 cpu_watchpoint_remove_by_ref(cs, env->cpu_watchpoint[i]);
138                 env->cpu_watchpoint[i] = NULL;
139             }
140         }
141     }
142     env->sregs[DBREAKC + i] = v;
143 }
144