semihosting: enable chardev backed output for console

It will be useful for a number of use-cases to be able to re-direct
output to a file like we do with serial output. This does the wiring
to allow us to treat then semihosting console like just another
character output device.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
This commit is contained in:
Alex Bennée 2019-05-14 15:30:14 +01:00
parent a331c6d774
commit 4e7f9032cf
6 changed files with 51 additions and 3 deletions

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@ -23,6 +23,7 @@
#include "qemu/config-file.h"
#include "qemu/error-report.h"
#include "hw/semihosting/semihost.h"
#include "chardev/char.h"
QemuOptsList qemu_semihosting_config_opts = {
.name = "semihosting-config",
@ -35,6 +36,9 @@ QemuOptsList qemu_semihosting_config_opts = {
}, {
.name = "target",
.type = QEMU_OPT_STRING,
}, {
.name = "chardev",
.type = QEMU_OPT_STRING,
}, {
.name = "arg",
.type = QEMU_OPT_STRING,
@ -46,12 +50,14 @@ QemuOptsList qemu_semihosting_config_opts = {
typedef struct SemihostingConfig {
bool enabled;
SemihostingTarget target;
Chardev *chardev;
const char **argv;
int argc;
const char *cmdline; /* concatenated argv */
} SemihostingConfig;
static SemihostingConfig semihosting;
static const char *semihost_chardev;
bool semihosting_enabled(void)
{
@ -115,6 +121,11 @@ void semihosting_arg_fallback(const char *file, const char *cmd)
}
}
Chardev *semihosting_get_chardev(void)
{
return semihosting.chardev;
}
void qemu_semihosting_enable(void)
{
semihosting.enabled = true;
@ -132,6 +143,8 @@ int qemu_semihosting_config_options(const char *optarg)
semihosting.enabled = qemu_opt_get_bool(opts, "enable",
true);
const char *target = qemu_opt_get(opts, "target");
/* setup of chardev is deferred until they are initialised */
semihost_chardev = qemu_opt_get(opts, "chardev");
if (target != NULL) {
if (strcmp("native", target) == 0) {
semihosting.target = SEMIHOSTING_TARGET_NATIVE;
@ -158,3 +171,16 @@ int qemu_semihosting_config_options(const char *optarg)
return 0;
}
void qemu_semihosting_connect_chardevs(void)
{
/* We had to defer this until chardevs were created */
if (semihost_chardev) {
Chardev *chr = qemu_chr_find(semihost_chardev);
if (chr == NULL) {
error_report("semihosting chardev '%s' not found",
semihost_chardev);
exit(1);
}
semihosting.chardev = chr;
}
}

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@ -17,13 +17,20 @@
#include "qemu/osdep.h"
#include "cpu.h"
#include "hw/semihosting/semihost.h"
#include "hw/semihosting/console.h"
#include "exec/gdbstub.h"
#include "qemu/log.h"
#include "chardev/char.h"
int qemu_semihosting_log_out(const char *s, int len)
{
Chardev *chardev = semihosting_get_chardev();
if (chardev) {
return qemu_chr_write_all(chardev, (uint8_t *) s, len);
} else {
return write(STDERR_FILENO, s, len);
}
}
/*

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@ -51,6 +51,11 @@ static inline const char *semihosting_get_cmdline(void)
{
return NULL;
}
static inline Chardev *semihosting_get_chardev(void)
{
return NULL;
}
#else /* !CONFIG_USER_ONLY */
bool semihosting_enabled(void);
SemihostingTarget semihosting_get_target(void);
@ -58,9 +63,11 @@ const char *semihosting_get_arg(int i);
int semihosting_get_argc(void);
const char *semihosting_get_cmdline(void);
void semihosting_arg_fallback(const char *file, const char *cmd);
Chardev *semihosting_get_chardev(void);
/* for vl.c hooks */
void qemu_semihosting_enable(void);
int qemu_semihosting_config_options(const char *opt);
void qemu_semihosting_connect_chardevs(void);
#endif /* CONFIG_USER_ONLY */
#endif /* SEMIHOST_H */

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@ -4025,12 +4025,12 @@ STEXI
Enable semihosting mode (ARM, M68K, Xtensa, MIPS, Nios II only).
ETEXI
DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config,
"-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \
"-semihosting-config [enable=on|off][,target=native|gdb|auto][,chardev=id][,arg=str[,...]]\n" \
" semihosting configuration\n",
QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
QEMU_ARCH_MIPS | QEMU_ARCH_NIOS2)
STEXI
@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]
@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,chardev=id][,arg=str[,...]]
@findex -semihosting-config
Enable and configure semihosting (ARM, M68K, Xtensa, MIPS, Nios II only).
@table @option
@ -4038,6 +4038,8 @@ Enable and configure semihosting (ARM, M68K, Xtensa, MIPS, Nios II only).
Defines where the semihosting calls will be addressed, to QEMU (@code{native})
or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb}
during debug sessions and @code{native} otherwise.
@item chardev=@var{str1}
Send the output to a chardev backend output for native or auto output when not in gdb
@item arg=@var{str1},arg=@var{str2},...
Allows the user to pass input arguments, and can be used multiple times to build
up a list. The old-style @code{-kernel}/@code{-append} method of passing a

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@ -64,3 +64,7 @@ const char *semihosting_get_cmdline(void)
void semihosting_arg_fallback(const char *file, const char *cmd)
{
}
void qemu_semihosting_connect_chardevs(void)
{
}

2
vl.c
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@ -4170,6 +4170,8 @@ int main(int argc, char **argv, char **envp)
qemu_opts_foreach(qemu_find_opts("chardev"),
chardev_init_func, NULL, &error_fatal);
/* now chardevs have been created we may have semihosting to connect */
qemu_semihosting_connect_chardevs();
#ifdef CONFIG_VIRTFS
qemu_opts_foreach(qemu_find_opts("fsdev"),