2 files changed, 161 insertions, 0 deletions
diff --git a/hw/semihosting/Makefile.objs b/hw/semihosting/Makefile.objs
new file mode 100644
index 0000000000..546954f4ff
--- /dev/null
+++ b/hw/semihosting/Makefile.objs
@@ -0,0 +1 @@
+common-obj-$(CONFIG_SOFTMMU) += config.o
diff --git a/hw/semihosting/config.c b/hw/semihosting/config.c
new file mode 100644
index 0000000000..f1d3fe1e4c
--- /dev/null
+++ b/hw/semihosting/config.c
@@ -0,0 +1,160 @@
+/*
+ * Semihosting configuration
+ *
+ * Copyright (c) 2015 Imagination Technologies
+ * Copyright (c) 2019 Linaro Ltd
+ *
+ * This controls the configuration of semihosting for all guest
+ * targets that support it. Architecture specific handling is handled
+ * in target/HW/HW-semi.c
+ *
+ * Semihosting is sightly strange in that it is also supported by some
+ * linux-user targets. However in that use case no configuration of
+ * the outputs and command lines is supported.
+ *
+ * The config module is common to all softmmu targets however as vl.c
+ * needs to link against the helpers.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/option.h"
+#include "qemu/config-file.h"
+#include "qemu/error-report.h"
+#include "hw/semihosting/semihost.h"
+
+QemuOptsList qemu_semihosting_config_opts = {
+    .name = "semihosting-config",
+    .implied_opt_name = "enable",
+    .head = QTAILQ_HEAD_INITIALIZER(qemu_semihosting_config_opts.head),
+    .desc = {
+        {
+            .name = "enable",
+            .type = QEMU_OPT_BOOL,
+        }, {
+            .name = "target",
+            .type = QEMU_OPT_STRING,
+        }, {
+            .name = "arg",
+            .type = QEMU_OPT_STRING,
+        },
+        { /* end of list */ }
+    },
+};
+
+typedef struct SemihostingConfig {
+    bool enabled;
+    SemihostingTarget target;
+    const char **argv;
+    int argc;
+    const char *cmdline; /* concatenated argv */
+} SemihostingConfig;
+
+static SemihostingConfig semihosting;
+
+bool semihosting_enabled(void)
+{
+    return semihosting.enabled;
+}
+
+SemihostingTarget semihosting_get_target(void)
+{
+    return semihosting.target;
+}
+
+const char *semihosting_get_arg(int i)
+{
+    if (i >= semihosting.argc) {
+        return NULL;
+    }
+    return semihosting.argv[i];
+}
+
+int semihosting_get_argc(void)
+{
+    return semihosting.argc;
+}
+
+const char *semihosting_get_cmdline(void)
+{
+    if (semihosting.cmdline == NULL && semihosting.argc > 0) {
+        semihosting.cmdline = g_strjoinv(" ", (gchar **)semihosting.argv);
+    }
+    return semihosting.cmdline;
+}
+
+static int add_semihosting_arg(void *opaque,
+                               const char *name, const char *val,
+                               Error **errp)
+{
+    SemihostingConfig *s = opaque;
+    if (strcmp(name, "arg") == 0) {
+        s->argc++;
+        /* one extra element as g_strjoinv() expects NULL-terminated array */
+        s->argv = g_realloc(s->argv, (s->argc + 1) * sizeof(void *));
+        s->argv[s->argc - 1] = val;
+        s->argv[s->argc] = NULL;
+    }
+    return 0;
+}
+
+/* Use strings passed via -kernel/-append to initialize semihosting.argv[] */
+void semihosting_arg_fallback(const char *file, const char *cmd)
+{
+    char *cmd_token;
+
+    /* argv[0] */
+    add_semihosting_arg(&semihosting, "arg", file, NULL);
+
+    /* split -append and initialize argv[1..n] */
+    cmd_token = strtok(g_strdup(cmd), " ");
+    while (cmd_token) {
+        add_semihosting_arg(&semihosting, "arg", cmd_token, NULL);
+        cmd_token = strtok(NULL, " ");
+    }
+}
+
+void qemu_semihosting_enable(void)
+{
+    semihosting.enabled = true;
+    semihosting.target = SEMIHOSTING_TARGET_AUTO;
+}
+
+int qemu_semihosting_config_options(const char *optarg)
+{
+    QemuOptsList *opt_list = qemu_find_opts("semihosting-config");
+    QemuOpts *opts = qemu_opts_parse_noisily(opt_list, optarg, false);
+
+    semihosting.enabled = true;
+
+    if (opts != NULL) {
+        semihosting.enabled = qemu_opt_get_bool(opts, "enable",
+                                                true);
+        const char *target = qemu_opt_get(opts, "target");
+        if (target != NULL) {
+            if (strcmp("native", target) == 0) {
+                semihosting.target = SEMIHOSTING_TARGET_NATIVE;
+            } else if (strcmp("gdb", target) == 0) {
+                semihosting.target = SEMIHOSTING_TARGET_GDB;
+            } else  if (strcmp("auto", target) == 0) {
+                semihosting.target = SEMIHOSTING_TARGET_AUTO;
+            } else {
+                error_report("unsupported semihosting-config %s",
+                             optarg);
+                return 1;
+            }
+        } else {
+            semihosting.target = SEMIHOSTING_TARGET_AUTO;
+        }
+        /* Set semihosting argument count and vector */
+        qemu_opt_foreach(opts, add_semihosting_arg,
+                         &semihosting, NULL);
+    } else {
+        error_report("unsupported semihosting-config %s", optarg);
+        return 1;
+    }
+
+    return 0;
+}
+