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
  28 QemuOptsList qemu_semihosting_config_opts = {
  29     .name = "semihosting-config",
  30     .implied_opt_name = "enable",
  31     .head = QTAILQ_HEAD_INITIALIZER(qemu_semihosting_config_opts.head),
  32     .desc = {
  33         {
  34             .name = "enable",
  35             .type = QEMU_OPT_BOOL,
  36         }, {
  37             .name = "target",
  38             .type = QEMU_OPT_STRING,
  39         }, {
  40             .name = "chardev",
  41             .type = QEMU_OPT_STRING,
  42         }, {
  43             .name = "arg",
  44             .type = QEMU_OPT_STRING,
  45         },
  46         { /* end of list */ }
  47     },
  48 };
  49
  50 typedef struct SemihostingConfig {
  51     bool enabled;
  52     SemihostingTarget target;
  53     Chardev *chardev;
  54     const 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_realloc(s->argv, (s->argc + 1) * sizeof(void *));
 102         s->argv[s->argc - 1] = 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 Chardev *semihosting_get_chardev(void)
 125 {
 126     return semihosting.chardev;
 127 }
 128
 129 void qemu_semihosting_enable(void)
 130 {
 131     semihosting.enabled = true;
 132     semihosting.target = SEMIHOSTING_TARGET_AUTO;
 133 }
 134
 135 int qemu_semihosting_config_options(const char *optarg)
 136 {
 137     QemuOptsList *opt_list = qemu_find_opts("semihosting-config");
 138     QemuOpts *opts = qemu_opts_parse_noisily(opt_list, optarg, false);
 139
 140     semihosting.enabled = true;
 141
 142     if (opts != NULL) {
 143         semihosting.enabled = qemu_opt_get_bool(opts, "enable",
 144                                                 true);
 145         const char *target = qemu_opt_get(opts, "target");
 146         /* setup of chardev is deferred until they are initialised */
 147         semihost_chardev = qemu_opt_get(opts, "chardev");
 148         if (target != NULL) {
 149             if (strcmp("native", target) == 0) {
 150                 semihosting.target = SEMIHOSTING_TARGET_NATIVE;
 151             } else if (strcmp("gdb", target) == 0) {
 152                 semihosting.target = SEMIHOSTING_TARGET_GDB;
 153             } else  if (strcmp("auto", target) == 0) {
 154                 semihosting.target = SEMIHOSTING_TARGET_AUTO;
 155             } else {
 156                 error_report("unsupported semihosting-config %s",
 157                              optarg);
 158                 return 1;
 159             }
 160         } else {
 161             semihosting.target = SEMIHOSTING_TARGET_AUTO;
 162         }
 163         /* Set semihosting argument count and vector */
 164         qemu_opt_foreach(opts, add_semihosting_arg,
 165                          &semihosting, NULL);
 166     } else {
 167         error_report("unsupported semihosting-config %s", optarg);
 168         return 1;
 169     }
 170
 171     return 0;
 172 }
 173
 174 void qemu_semihosting_connect_chardevs(void)
 175 {
 176     /* We had to defer this until chardevs were created */
 177     if (semihost_chardev) {
 178         Chardev *chr = qemu_chr_find(semihost_chardev);
 179         if (chr == NULL) {
 180             error_report("semihosting chardev '%s' not found",
 181                          semihost_chardev);
 182             exit(1);
 183         }
 184         semihosting.chardev = chr;
 185     }
 186 }