Miroslav Rezanina <mreza...@redhat.com> writes:
> On Tue, May 14, 2019 at 04:52:56PM +0100, Alex Bennée wrote:
>> Now we have a common semihosting console interface use that for our
>> string output. However ARM is currently unique in also supporting
>> semihosting for linux-user so we need to replicate the API in
>> linux-user. If other architectures gain this support we can move the
>> file later.
>>
>> Signed-off-by: Alex Bennée <alex.ben...@linaro.org>
>> ---
>> linux-user/Makefile.objs | 2 ++
>> linux-user/arm/semihost.c | 24 ++++++++++++++++++++++++
>> target/arm/arm-semi.c | 31 ++++++-------------------------
>> 3 files changed, 32 insertions(+), 25 deletions(-)
>> create mode 100644 linux-user/arm/semihost.c
>>
>> diff --git a/linux-user/Makefile.objs b/linux-user/Makefile.objs
>> index 769b8d83362..285c5dfa17a 100644
>> --- a/linux-user/Makefile.objs
>> +++ b/linux-user/Makefile.objs
>> @@ -6,4 +6,6 @@ obj-y = main.o syscall.o strace.o mmap.o signal.o \
>> obj-$(TARGET_HAS_BFLT) += flatload.o
>> obj-$(TARGET_I386) += vm86.o
>> obj-$(TARGET_ARM) += arm/nwfpe/
>> +obj-$(TARGET_ARM) += arm/semihost.o
>> +obj-$(TARGET_AARCH64) += arm/semihost.o
>> obj-$(TARGET_M68K) += m68k-sim.o
>> diff --git a/linux-user/arm/semihost.c b/linux-user/arm/semihost.c
>> new file mode 100644
>> index 00000000000..9554102a855
>> --- /dev/null
>> +++ b/linux-user/arm/semihost.c
>> @@ -0,0 +1,24 @@
>> +/*
>> + * ARM Semihosting Console Support
>> + *
>> + * Copyright (c) 2019 Linaro Ltd
>> + *
>> + * Currently ARM is unique in having support for semihosting support
>> + * in linux-user. So for now we implement the common console API but
>> + * just for arm linux-user.
>> + *
>> + * SPDX-License-Identifier: GPL-2.0-or-later
>> + */
>> +
>> +#include "qemu/osdep.h"
>> +#include "cpu.h"
>> +#include "hw/semihosting/console.h"
>> +#include "qemu.h"
>> +
>> +int qemu_semihosting_console_out(CPUArchState *env, target_ulong addr, int
>> len)
>> +{
>> + void *s = lock_user_string(addr);
>> + len = write(STDERR_FILENO, s, len ? len : strlen(s));
>> + unlock_user(s, addr, 0);
>> + return len;
>> +}
>> diff --git a/target/arm/arm-semi.c b/target/arm/arm-semi.c
>> index 9e5a414dd89..253c66b172a 100644
>> --- a/target/arm/arm-semi.c
>> +++ b/target/arm/arm-semi.c
>> @@ -27,6 +27,7 @@
>>
>> #include "cpu.h"
>> #include "hw/semihosting/semihost.h"
>> +#include "hw/semihosting/console.h"
>> #ifdef CONFIG_USER_ONLY
>> #include "qemu.h"
>>
>> @@ -314,32 +315,12 @@ target_ulong do_arm_semihosting(CPUARMState *env)
>> return set_swi_errno(ts, close(arg0));
>> }
>> case TARGET_SYS_WRITEC:
>> - {
>> - char c;
>> -
>> - if (get_user_u8(c, args))
>> - /* FIXME - should this error code be -TARGET_EFAULT ? */
>> - return (uint32_t)-1;
>> - /* Write to debug console. stderr is near enough. */
>> - if (use_gdb_syscalls()) {
>> - return arm_gdb_syscall(cpu, arm_semi_cb, "write,2,%x,1",
>> args);
>> - } else {
>> - return write(STDERR_FILENO, &c, 1);
>> - }
>> - }
>> + {
>> + qemu_semihosting_console_out(env, args, 1);
>> + return 0xdeadbeef;
>> + }
>> case TARGET_SYS_WRITE0:
>> - if (!(s = lock_user_string(args)))
>> - /* FIXME - should this error code be -TARGET_EFAULT ? */
>> - return (uint32_t)-1;
>> - len = strlen(s);
>> - if (use_gdb_syscalls()) {
>> - return arm_gdb_syscall(cpu, arm_semi_cb, "write,2,%x,%x",
>> - args, len);
>> - } else {
>> - ret = write(STDERR_FILENO, s, len);
>> - }
>> - unlock_user(s, args, 0);
>> - return ret;
>> + return qemu_semihosting_console_out(env, args, 0);
>> case TARGET_SYS_WRITE:
>> GET_ARG(0);
>> GET_ARG(1);
>> --
>> 2.20.1
>>
>>
>
> Hi Alex,
>
> this patch breaks build for softmmu target when CONFIG_SEMIHOSTING is not
> enabled as qemu_semihosting_console_out
> is not defined in such case - neither linux-user/arm/semihost.c nor
> hw/semihosting/console.c compiled and function
> is not in stubs/semihost.c
How do you do that? I tried ../../configure --without-default-devices
and that still builds for me.
But I suspect what's needed is to change:
#ifndef CONFIG_USER_ONLY
to
#ifdef CONFIG_SEMIHOSTING
to the relevant headers and helper bits.
>
> Mirek
--
Alex Bennée
