1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
|
/*
* Copyright 2014 Broadcom Corporation
*
* SPDX-License-Identifier: GPL-2.0+
*/
/*
* Minimal semihosting implementation for reading files into memory. If more
* features like writing files or console output are required they can be
* added later. This code has been tested on arm64/aarch64 fastmodel only.
* An untested placeholder exists for armv7 architectures, but since they
* are commonly available in silicon now, fastmodel usage makes less sense
* for them.
*/
#include <common.h>
#include <command.h>
#define SYSOPEN 0x01
#define SYSCLOSE 0x02
#define SYSREAD 0x06
#define SYSFLEN 0x0C
#define MODE_READ 0x0
#define MODE_READBIN 0x1
/*
* Call the handler
*/
static noinline long smh_trap(unsigned int sysnum, void *addr)
{
register long result asm("r0");
#if defined(CONFIG_ARM64)
asm volatile ("hlt #0xf000" : "=r" (result) : "0"(sysnum), "r"(addr));
#elif defined(CONFIG_CPU_V7M)
asm volatile ("bkpt #0xAB" : "=r" (result) : "0"(sysnum), "r"(addr));
#else
/* Note - untested placeholder */
asm volatile ("svc #0x123456" : "=r" (result) : "0"(sysnum), "r"(addr));
#endif
return result;
}
/*
* Open a file on the host. Mode is "r" or "rb" currently. Returns a file
* descriptor or -1 on error.
*/
static long smh_open(const char *fname, char *modestr)
{
long fd;
unsigned long mode;
struct smh_open_s {
const char *fname;
unsigned long mode;
size_t len;
} open;
debug("%s: file \'%s\', mode \'%s\'\n", __func__, fname, modestr);
/* Check the file mode */
if (!(strcmp(modestr, "r"))) {
mode = MODE_READ;
} else if (!(strcmp(modestr, "rb"))) {
mode = MODE_READBIN;
} else {
printf("%s: ERROR mode \'%s\' not supported\n", __func__,
modestr);
return -1;
}
open.fname = fname;
open.len = strlen(fname);
open.mode = mode;
/* Open the file on the host */
fd = smh_trap(SYSOPEN, &open);
if (fd == -1)
printf("%s: ERROR fd %ld for file \'%s\'\n", __func__, fd,
fname);
return fd;
}
/*
* Read 'len' bytes of file into 'memp'. Returns 0 on success, else failure
*/
static long smh_read(long fd, void *memp, size_t len)
{
long ret;
struct smh_read_s {
long fd;
void *memp;
size_t len;
} read;
debug("%s: fd %ld, memp %p, len %zu\n", __func__, fd, memp, len);
read.fd = fd;
read.memp = memp;
read.len = len;
ret = smh_trap(SYSREAD, &read);
if (ret < 0) {
/*
* The ARM handler allows for returning partial lengths,
* but in practice this never happens so rather than create
* hard to maintain partial read loops and such, just fail
* with an error message.
*/
printf("%s: ERROR ret %ld, fd %ld, len %zu memp %p\n",
__func__, ret, fd, len, memp);
return -1;
}
return 0;
}
/*
* Close the file using the file descriptor
*/
static long smh_close(long fd)
{
long ret;
debug("%s: fd %ld\n", __func__, fd);
ret = smh_trap(SYSCLOSE, &fd);
if (ret == -1)
printf("%s: ERROR fd %ld\n", __func__, fd);
return ret;
}
/*
* Get the file length from the file descriptor
*/
static long smh_len_fd(long fd)
{
long ret;
debug("%s: fd %ld\n", __func__, fd);
ret = smh_trap(SYSFLEN, &fd);
if (ret == -1)
printf("%s: ERROR ret %ld, fd %ld\n", __func__, ret, fd);
return ret;
}
static int smh_load_file(const char * const name, ulong load_addr,
ulong *end_addr)
{
long fd;
long len;
long ret;
fd = smh_open(name, "rb");
if (fd == -1)
return -1;
len = smh_len_fd(fd);
if (len < 0) {
smh_close(fd);
return -1;
}
ret = smh_read(fd, (void *)load_addr, len);
smh_close(fd);
if (ret == 0) {
*end_addr = load_addr + len - 1;
printf("loaded file %s from %08lX to %08lX, %08lX bytes\n",
name,
load_addr,
*end_addr,
len);
} else {
printf("read failed\n");
return 0;
}
return 0;
}
static int do_smhload(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
if (argc == 3 || argc == 4) {
ulong load_addr;
ulong end_addr = 0;
int ret;
char end_str[64];
load_addr = simple_strtoul(argv[2], NULL, 16);
if (!load_addr)
return -1;
ret = smh_load_file(argv[1], load_addr, &end_addr);
if (ret < 0)
return CMD_RET_FAILURE;
/* Optionally save returned end to the environment */
if (argc == 4) {
sprintf(end_str, "0x%08lx", end_addr);
env_set(argv[3], end_str);
}
} else {
return CMD_RET_USAGE;
}
return 0;
}
U_BOOT_CMD(smhload, 4, 0, do_smhload, "load a file using semihosting",
"<file> 0x<address> [end var]\n"
" - load a semihosted file to the address specified\n"
" if the optional [end var] is specified, the end\n"
" address of the file will be stored in this environment\n"
" variable.\n");
|
