xref: /openbmc/qemu/semihosting/config.c (revision 4e245a9e)
1 /*
2  * Semihosting configuration
3  *
4  * Copyright (c) 2015 Imagination Technologies
5  * Copyright (c) 2019 Linaro Ltd
6  *
7  * This controls the configuration of semihosting for all guest
8  * targets that support it. Architecture specific handling is handled
9  * in target/HW/HW-semi.c
10  *
11  * Semihosting is sightly strange in that it is also supported by some
12  * linux-user targets. However in that use case no configuration of
13  * the outputs and command lines is supported.
14  *
15  * The config module is common to all softmmu targets however as vl.c
16  * needs to link against the helpers.
17  *
18  * SPDX-License-Identifier: GPL-2.0-or-later
19  */
20 
21 #include "qemu/osdep.h"
22 #include "qemu/option.h"
23 #include "qemu/config-file.h"
24 #include "qemu/error-report.h"
25 #include "semihosting/semihost.h"
26 #include "chardev/char.h"
27 
28 QemuOptsList qemu_semihosting_config_opts = {
29     .name = "semihosting-config",
30     .merge_lists = true,
31     .implied_opt_name = "enable",
32     .head = QTAILQ_HEAD_INITIALIZER(qemu_semihosting_config_opts.head),
33     .desc = {
34         {
35             .name = "enable",
36             .type = QEMU_OPT_BOOL,
37         }, {
38             .name = "target",
39             .type = QEMU_OPT_STRING,
40         }, {
41             .name = "chardev",
42             .type = QEMU_OPT_STRING,
43         }, {
44             .name = "arg",
45             .type = QEMU_OPT_STRING,
46         },
47         { /* end of list */ }
48     },
49 };
50 
51 typedef struct SemihostingConfig {
52     bool enabled;
53     SemihostingTarget target;
54     char **argv;
55     int argc;
56     const char *cmdline; /* concatenated argv */
57 } SemihostingConfig;
58 
59 static SemihostingConfig semihosting;
60 static const char *semihost_chardev;
61 
62 bool semihosting_enabled(void)
63 {
64     return semihosting.enabled;
65 }
66 
67 SemihostingTarget semihosting_get_target(void)
68 {
69     return semihosting.target;
70 }
71 
72 const char *semihosting_get_arg(int i)
73 {
74     if (i >= semihosting.argc) {
75         return NULL;
76     }
77     return semihosting.argv[i];
78 }
79 
80 int semihosting_get_argc(void)
81 {
82     return semihosting.argc;
83 }
84 
85 const char *semihosting_get_cmdline(void)
86 {
87     if (semihosting.cmdline == NULL && semihosting.argc > 0) {
88         semihosting.cmdline = g_strjoinv(" ", (gchar **)semihosting.argv);
89     }
90     return semihosting.cmdline;
91 }
92 
93 static int add_semihosting_arg(void *opaque,
94                                const char *name, const char *val,
95                                Error **errp)
96 {
97     SemihostingConfig *s = opaque;
98     if (strcmp(name, "arg") == 0) {
99         s->argc++;
100         /* one extra element as g_strjoinv() expects NULL-terminated array */
101         s->argv = g_renew(char *, s->argv, s->argc + 1);
102         s->argv[s->argc - 1] = g_strdup(val);
103         s->argv[s->argc] = NULL;
104     }
105     return 0;
106 }
107 
108 /* Use strings passed via -kernel/-append to initialize semihosting.argv[] */
109 void semihosting_arg_fallback(const char *file, const char *cmd)
110 {
111     char *cmd_token;
112 
113     /* argv[0] */
114     add_semihosting_arg(&semihosting, "arg", file, NULL);
115 
116     /* split -append and initialize argv[1..n] */
117     cmd_token = strtok(g_strdup(cmd), " ");
118     while (cmd_token) {
119         add_semihosting_arg(&semihosting, "arg", cmd_token, NULL);
120         cmd_token = strtok(NULL, " ");
121     }
122 }
123 
124 void qemu_semihosting_enable(void)
125 {
126     semihosting.enabled = true;
127     semihosting.target = SEMIHOSTING_TARGET_AUTO;
128 }
129 
130 int qemu_semihosting_config_options(const char *optarg)
131 {
132     QemuOptsList *opt_list = qemu_find_opts("semihosting-config");
133     QemuOpts *opts = qemu_opts_parse_noisily(opt_list, optarg, false);
134 
135     semihosting.enabled = true;
136 
137     if (opts != NULL) {
138         semihosting.enabled = qemu_opt_get_bool(opts, "enable",
139                                                 true);
140         const char *target = qemu_opt_get(opts, "target");
141         /* setup of chardev is deferred until they are initialised */
142         semihost_chardev = qemu_opt_get(opts, "chardev");
143         if (target != NULL) {
144             if (strcmp("native", target) == 0) {
145                 semihosting.target = SEMIHOSTING_TARGET_NATIVE;
146             } else if (strcmp("gdb", target) == 0) {
147                 semihosting.target = SEMIHOSTING_TARGET_GDB;
148             } else  if (strcmp("auto", target) == 0) {
149                 semihosting.target = SEMIHOSTING_TARGET_AUTO;
150             } else {
151                 error_report("unsupported semihosting-config %s",
152                              optarg);
153                 return 1;
154             }
155         } else {
156             semihosting.target = SEMIHOSTING_TARGET_AUTO;
157         }
158         /* Set semihosting argument count and vector */
159         qemu_opt_foreach(opts, add_semihosting_arg,
160                          &semihosting, NULL);
161     } else {
162         error_report("unsupported semihosting-config %s", optarg);
163         return 1;
164     }
165 
166     return 0;
167 }
168 
169 /* We had to defer this until chardevs were created */
170 void qemu_semihosting_chardev_init(void)
171 {
172     Chardev *chr = NULL;
173 
174     if (semihost_chardev) {
175         chr = qemu_chr_find(semihost_chardev);
176         if (chr == NULL) {
177             error_report("semihosting chardev '%s' not found",
178                          semihost_chardev);
179             exit(1);
180         }
181     }
182 
183     qemu_semihosting_console_init(chr);
184 }
185