Re: [PATCH 06/12] tests/tcg/riscv64: Enable multiarch system tests

[Alistair Francis <Alistair.Francis@wdc.com>]

On Thu, 2026-08-27 at 14:39 +0930, Joel Stanley wrote:
> Add the boot code and semihosting helpers needed to run the multiarch
> system tests on riscv64, and add riscv64 to
> MULTIARCH_SOFTMMU_TARGETS.
> The aarch64 makefile was used as a guide for the make rules.
> 
> boot.S does not clear bss as the libmem plugin test would count the
> stores and fail with a mismatch. Instead the BSS is described as
> PT_LOAD, so the QEMU ELF loader fills the region with zero, the same
> as
> aarch64 and loongarch64.
> 
> Signed-off-by: Joel Stanley <joel@jms.id.au>

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Alistair

> ---
>  tests/tcg/riscv64/system.c                | 30 +++++++++++++++++
>  tests/tcg/Makefile.target                 |  2 +-
>  tests/tcg/riscv64/Makefile.softmmu-target | 40 ++++++++++++---------
> --
>  tests/tcg/riscv64/boot.S                  | 23 +++++++++++++
>  4 files changed, 75 insertions(+), 20 deletions(-)
>  create mode 100644 tests/tcg/riscv64/system.c
>  create mode 100644 tests/tcg/riscv64/boot.S
> 
> diff --git a/tests/tcg/riscv64/system.c b/tests/tcg/riscv64/system.c
> new file mode 100644
> index 000000000000..08196a540f96
> --- /dev/null
> +++ b/tests/tcg/riscv64/system.c
> @@ -0,0 +1,30 @@
> +/*
> + * RISC-V semihosting support for multiarch test suite
> + *
> + * Copyright 2026 Tenstorrent USA Inc
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +
> +#include "semicall.h"
> +
> +#define SYS_WRITEC      0x3
> +#define SYS_EXIT        0x18
> +
> +#define ADP_Stopped_ApplicationExit 0x20026
> +
> +void __sys_outc(char c)
> +{
> +    __semi_call(SYS_WRITEC, (uintptr_t)&c);
> +}
> +
> +void _exit(int code)
> +{
> +    const uintptr_t args[2] = { ADP_Stopped_ApplicationExit,
> (uintptr_t)code };
> +
> +    __semi_call(SYS_EXIT, (uintptr_t)args);
> +
> +    /* Hang if QEMU fails to exit */
> +    while (1) {
> +        asm volatile("wfi");
> +    }
> +}
> diff --git a/tests/tcg/Makefile.target b/tests/tcg/Makefile.target
> index 1b83824ff4e7..d4dd0fec650d 100644
> --- a/tests/tcg/Makefile.target
> +++ b/tests/tcg/Makefile.target
> @@ -129,7 +129,7 @@ else
>  EXTRA_CFLAGS += -ffreestanding -fno-stack-protector
>  
>  # We skip the multiarch tests if the target hasn't provided a boot.S
> -MULTIARCH_SOFTMMU_TARGETS = i386 alpha aarch64 arm loongarch64 s390x
> x86_64
> +MULTIARCH_SOFTMMU_TARGETS = i386 alpha aarch64 arm loongarch64 s390x
> x86_64 riscv64
>  
>  ifneq ($(filter $(TARGET_NAME),$(MULTIARCH_SOFTMMU_TARGETS)),)
>  -include $(SRC_PATH)/tests/tcg/minilib/Makefile.target
> diff --git a/tests/tcg/riscv64/Makefile.softmmu-target
> b/tests/tcg/riscv64/Makefile.softmmu-target
> index f2850a194084..82e8fe2664b0 100644
> --- a/tests/tcg/riscv64/Makefile.softmmu-target
> +++ b/tests/tcg/riscv64/Makefile.softmmu-target
> @@ -5,9 +5,11 @@
>  TEST_SRC = $(SRC_PATH)/tests/tcg/riscv64
>  VPATH += $(TEST_SRC)
>  
> +CRT_OBJS = boot.o system.o
> +
>  LINK_SCRIPT = $(TEST_SRC)/semihost.ld
> -LDFLAGS = -T $(LINK_SCRIPT)
> -CFLAGS += -g -Og
> +LDFLAGS = -Wl,-T$(LINK_SCRIPT) -static -nostdlib $(MINILIB_OBJS) -
> lgcc
> +CFLAGS += -g -Og $(MINILIB_INC)
>  
>  # Used by riscv64 tcg tests and shared 'multiarch' tests
>  QEMU_CPU = rv64
> @@ -53,23 +55,23 @@ test-zicclsm-off.o: test-zicclsm.S
>  	$(call quiet-command, \
>  	  $(CC) $(CFLAGS) $< -Wa$(COMMA)--noexecstack -c -o $@, CC,
> $@)
>  
> -EXTRA_RUNS += run-plugin-doubletrap
> -run-plugin-doubletrap: doubletrap
> -	$(call run-test, $<, \
> -	  $(QEMU) -monitor none -display none \
> -		  -chardev file$(COMMA)path=$<.out$(COMMA)id=output
> \
> -		  -plugin ../plugins/libdiscons.so -d plugin -D
> $<.pout \
> -		  $(QEMU_OPTS) $<)
> -
> -EXTRA_RUNS += run-plugin-interruptedmemory
> -run-plugin-interruptedmemory: interruptedmemory
> -	$(call run-test, $<, \
> -	  $(QEMU) -monitor none -display none \
> -		  -chardev file$(COMMA)path=$<.out$(COMMA)id=output
> \
> -		  -plugin ../plugins/libdiscons.so -d plugin -D
> $<.pout \
> -		  $(QEMU_OPTS) $<)
> +ifeq ($(CONFIG_PLUGIN),y)
> +EXTRA_RUNS_WITH_PLUGIN += run-plugin-doubletrap-with-libdiscons.so \
> +	run-plugin-interruptedmemory-with-libdiscons.so
> +endif
>  
>  CLEANFILES += interruptedmemory doubletrap
>  
> -# We don't currently support the multiarch system tests
> -undefine MULTIARCH_TESTS
> +# Multiarch tests
> +TESTS += $(MULTIARCH_TESTS)
> +EXTRA_RUNS += $(MULTIARCH_RUNS)
> +
> +.PRECIOUS: $(CRT_OBJS)
> +
> +# Build and link the multiarch tests
> +%: %.c $(LINK_SCRIPT) $(CRT_OBJS) $(MINILIB_OBJS)
> +	$(call quiet-command, \
> +	 $(CC) $(CFLAGS) $(EXTRA_CFLAGS) $< -o $@ $(LDFLAGS)
> $(CRT_OBJS), CC, $@)
> +
> +# Default is zicclsm=true, so misaligned accesses must work
> +memory: private CFLAGS += -DCHECK_UNALIGNED=1
> diff --git a/tests/tcg/riscv64/boot.S b/tests/tcg/riscv64/boot.S
> new file mode 100644
> index 000000000000..b403549345a1
> --- /dev/null
> +++ b/tests/tcg/riscv64/boot.S
> @@ -0,0 +1,23 @@
> +/*
> + * RISC-V boot code for multiarch test suite
> + *
> + * Copyright 2026 Tenstorrent USA Inc
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +
> +#define MSTATUS_VS          0x00000600
> +#define MSTATUS_FS          0x00006000
> +
> +.section .text._start
> +        .global _start
> +        .type _start, @function
> +_start:
> +        /* Enable FPU and vector unit */
> +        li      t0, (MSTATUS_FS | MSTATUS_VS)
> +        csrs    mstatus, t0
> +        la      sp, __stack_top
> +        call    main
> +
> +exit:
> +        /* exit with main()'s return code */
> +        call    _exit