xref: /openbmc/qemu/include/gdbstub/helpers.h (revision 651ccdfa)
1 /*
2  * gdbstub helpers
3  *
4  * These are all used by the various frontends and have to be host
5  * aware to ensure things are store in target order.
6  *
7  * Copyright (c) 2022 Linaro Ltd
8  *
9  * SPDX-License-Identifier: GPL-2.0-or-later
10  */
11 
12 #ifndef _GDBSTUB_HELPERS_H_
13 #define _GDBSTUB_HELPERS_H_
14 
15 #ifdef NEED_CPU_H
16 #include "cpu.h"
17 
18 /*
19  * The GDB remote protocol transfers values in target byte order. As
20  * the gdbstub may be batching up several register values we always
21  * append to the array.
22  */
23 
24 static inline int gdb_get_reg8(GByteArray *buf, uint8_t val)
25 {
26     g_byte_array_append(buf, &val, 1);
27     return 1;
28 }
29 
30 static inline int gdb_get_reg16(GByteArray *buf, uint16_t val)
31 {
32     uint16_t to_word = tswap16(val);
33     g_byte_array_append(buf, (uint8_t *) &to_word, 2);
34     return 2;
35 }
36 
37 static inline int gdb_get_reg32(GByteArray *buf, uint32_t val)
38 {
39     uint32_t to_long = tswap32(val);
40     g_byte_array_append(buf, (uint8_t *) &to_long, 4);
41     return 4;
42 }
43 
44 static inline int gdb_get_reg64(GByteArray *buf, uint64_t val)
45 {
46     uint64_t to_quad = tswap64(val);
47     g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
48     return 8;
49 }
50 
51 static inline int gdb_get_reg128(GByteArray *buf, uint64_t val_hi,
52                                  uint64_t val_lo)
53 {
54     uint64_t to_quad;
55 #if TARGET_BIG_ENDIAN
56     to_quad = tswap64(val_hi);
57     g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
58     to_quad = tswap64(val_lo);
59     g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
60 #else
61     to_quad = tswap64(val_lo);
62     g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
63     to_quad = tswap64(val_hi);
64     g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
65 #endif
66     return 16;
67 }
68 
69 static inline int gdb_get_zeroes(GByteArray *array, size_t len)
70 {
71     guint oldlen = array->len;
72     g_byte_array_set_size(array, oldlen + len);
73     memset(array->data + oldlen, 0, len);
74 
75     return len;
76 }
77 
78 /**
79  * gdb_get_reg_ptr: get pointer to start of last element
80  * @len: length of element
81  *
82  * This is a helper function to extract the pointer to the last
83  * element for additional processing. Some front-ends do additional
84  * dynamic swapping of the elements based on CPU state.
85  */
86 static inline uint8_t *gdb_get_reg_ptr(GByteArray *buf, int len)
87 {
88     return buf->data + buf->len - len;
89 }
90 
91 #if TARGET_LONG_BITS == 64
92 #define gdb_get_regl(buf, val) gdb_get_reg64(buf, val)
93 #define ldtul_p(addr) ldq_p(addr)
94 #else
95 #define gdb_get_regl(buf, val) gdb_get_reg32(buf, val)
96 #define ldtul_p(addr) ldl_p(addr)
97 #endif
98 
99 #else
100 #error "gdbstub helpers should only be included by target specific code"
101 #endif
102 
103 #endif /* _GDBSTUB_HELPERS_H_ */
104