semihosting/config.c

   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 #include "sysemu/sysemu.h"
  28
  29 QemuOptsList qemu_semihosting_config_opts = {
  30     .name = "semihosting-config",
  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     Chardev *chardev;
  55     const char **argv;
  56     int argc;
  57     const char *cmdline; /* concatenated argv */
  58 } SemihostingConfig;
  59
  60 static SemihostingConfig semihosting;
  61 static const char *semihost_chardev;
  62
  63 bool semihosting_enabled(void)
  64 {
  65     return semihosting.enabled;
  66 }
  67
  68 SemihostingTarget semihosting_get_target(void)
  69 {
  70     return semihosting.target;
  71 }
  72
  73 const char *semihosting_get_arg(int i)
  74 {
  75     if (i >= semihosting.argc) {
  76         return NULL;
  77     }
  78     return semihosting.argv[i];
  79 }
  80
  81 int semihosting_get_argc(void)
  82 {
  83     return semihosting.argc;
  84 }
  85
  86 const char *semihosting_get_cmdline(void)
  87 {
  88     if (semihosting.cmdline == NULL && semihosting.argc > 0) {
  89         semihosting.cmdline = g_strjoinv(" ", (gchar **)semihosting.argv);
  90     }
  91     return semihosting.cmdline;
  92 }
  93
  94 static int add_semihosting_arg(void *opaque,
  95                                const char *name, const char *val,
  96                                Error **errp)
  97 {
  98     SemihostingConfig *s = opaque;
  99     if (strcmp(name, "arg") == 0) {
 100         s->argc++;
 101         /* one extra element as g_strjoinv() expects NULL-terminated array */
 102         s->argv = g_realloc(s->argv, (s->argc + 1) * sizeof(void *));
 103         s->argv[s->argc - 1] = val;
 104         s->argv[s->argc] = NULL;
 105     }
 106     return 0;
 107 }
 108
 109 /* Use strings passed via -kernel/-append to initialize semihosting.argv[] */
 110 void semihosting_arg_fallback(const char *file, const char *cmd)
 111 {
 112     char *cmd_token;
 113
 114     /* argv[0] */
 115     add_semihosting_arg(&semihosting, "arg", file, NULL);
 116
 117     /* split -append and initialize argv[1..n] */
 118     cmd_token = strtok(g_strdup(cmd), " ");
 119     while (cmd_token) {
 120         add_semihosting_arg(&semihosting, "arg", cmd_token, NULL);
 121         cmd_token = strtok(NULL, " ");
 122     }
 123 }
 124
 125 Chardev *semihosting_get_chardev(void)
 126 {
 127     return semihosting.chardev;
 128 }
 129
 130 void qemu_semihosting_enable(void)
 131 {
 132     semihosting.enabled = true;
 133     semihosting.target = SEMIHOSTING_TARGET_AUTO;
 134 }
 135
 136 int qemu_semihosting_config_options(const char *optarg)
 137 {
 138     QemuOptsList *opt_list = qemu_find_opts("semihosting-config");
 139     QemuOpts *opts = qemu_opts_parse_noisily(opt_list, optarg, false);
 140
 141     semihosting.enabled = true;
 142
 143     if (opts != NULL) {
 144         semihosting.enabled = qemu_opt_get_bool(opts, "enable",
 145                                                 true);
 146         const char *target = qemu_opt_get(opts, "target");
 147         /* setup of chardev is deferred until they are initialised */
 148         semihost_chardev = qemu_opt_get(opts, "chardev");
 149         if (target != NULL) {
 150             if (strcmp("native", target) == 0) {
 151                 semihosting.target = SEMIHOSTING_TARGET_NATIVE;
 152             } else if (strcmp("gdb", target) == 0) {
 153                 semihosting.target = SEMIHOSTING_TARGET_GDB;
 154             } else  if (strcmp("auto", target) == 0) {
 155                 semihosting.target = SEMIHOSTING_TARGET_AUTO;
 156             } else {
 157                 error_report("unsupported semihosting-config %s",
 158                              optarg);
 159                 return 1;
 160             }
 161         } else {
 162             semihosting.target = SEMIHOSTING_TARGET_AUTO;
 163         }
 164         /* Set semihosting argument count and vector */
 165         qemu_opt_foreach(opts, add_semihosting_arg,
 166                          &semihosting, NULL);
 167     } else {
 168         error_report("unsupported semihosting-config %s", optarg);
 169         return 1;
 170     }
 171
 172     return 0;
 173 }
 174
 175 void qemu_semihosting_connect_chardevs(void)
 176 {
 177     /* We had to defer this until chardevs were created */
 178     if (semihost_chardev) {
 179         Chardev *chr = qemu_chr_find(semihost_chardev);
 180         if (chr == NULL) {
 181             error_report("semihosting chardev '%s' not found",
 182                          semihost_chardev);
 183             exit(1);
 184         }
 185         semihosting.chardev = chr;
 186     }
 187 }