[kvm-unit-tests PATCH v4 2/5] riscv: use asm-offsets to generate SBI_EXT_HSM values

[Clément Léger]

On 07/01/2025 18:27, Andrew Jones wrote:
> On Mon, Nov 25, 2024 at 05:21:51PM +0100, Clément Léger wrote:
>> Replace hardcoded values with generated ones using asm-offset. This
>> allows to directly use ASM_SBI_EXT_HSM and ASM_SBI_EXT_HSM_START in
> 
> ASM_SBI_EXT_HSM_HART_STOP
> 
>> assembly.
>>
>> Signed-off-by: Clément Léger <cleger at rivosinc.com>
>> ---
>>  riscv/Makefile           |  2 +-
>>  riscv/sbi-asm.S          |  6 ++++--
>>  riscv/asm-offsets-test.c | 12 ++++++++++++
>>  riscv/.gitignore         |  1 +
>>  4 files changed, 18 insertions(+), 3 deletions(-)
>>  create mode 100644 riscv/asm-offsets-test.c
>>  create mode 100644 riscv/.gitignore
>>
>> diff --git a/riscv/Makefile b/riscv/Makefile
>> index 28b04156..a01ff8a3 100644
>> --- a/riscv/Makefile
>> +++ b/riscv/Makefile
>> @@ -86,7 +86,7 @@ CFLAGS += -ffreestanding
>>  CFLAGS += -O2
>>  CFLAGS += -I $(SRCDIR)/lib -I $(SRCDIR)/lib/libfdt -I lib -I $(SRCDIR)/riscv
>>  
>> -asm-offsets = lib/riscv/asm-offsets.h
>> +asm-offsets = lib/riscv/asm-offsets.h riscv/asm-offsets-test.h
>>  include $(SRCDIR)/scripts/asm-offsets.mak
>>  
>>  %.aux.o: $(SRCDIR)/lib/auxinfo.c
>> diff --git a/riscv/sbi-asm.S b/riscv/sbi-asm.S
>> index 923c2cec..193d9606 100644
>> --- a/riscv/sbi-asm.S
>> +++ b/riscv/sbi-asm.S
>> @@ -7,6 +7,8 @@
>>  #define __ASSEMBLY__
>>  #include <asm/asm.h>
>>  #include <asm/csr.h>
>> +#include <asm/asm-offsets.h>
>> +#include <generated/asm-offsets-test.h>
>>  
>>  #include "sbi-tests.h"
>>  
>> @@ -58,8 +60,8 @@ sbi_hsm_check:
>>  7:	lb	t0, 0(t1)
>>  	pause
>>  	beqz	t0, 7b
>> -	li	a7, 0x48534d	/* SBI_EXT_HSM */
>> -	li	a6, 1		/* SBI_EXT_HSM_HART_STOP */
>> +	li	a7, ASM_SBI_EXT_HSM
>> +	li	a6, ASM_SBI_EXT_HSM_HART_STOP
>>  	ecall
>>  8:	pause
>>  	j	8b
>> diff --git a/riscv/asm-offsets-test.c b/riscv/asm-offsets-test.c
>> new file mode 100644
>> index 00000000..116fe497
>> --- /dev/null
>> +++ b/riscv/asm-offsets-test.c
>> @@ -0,0 +1,12 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +#include <kbuild.h>
>> +#include <asm/sbi.h>
>> +#include "sbi-tests.h"
>> +
>> +int main(void)
>> +{
>> +	DEFINE(ASM_SBI_EXT_HSM, SBI_EXT_HSM);
>> +	DEFINE(ASM_SBI_EXT_HSM_HART_STOP, SBI_EXT_HSM_HART_STOP);
>> +
>> +	return 0;
>> +}
>> diff --git a/riscv/.gitignore b/riscv/.gitignore
>> new file mode 100644
>> index 00000000..91713581
>> --- /dev/null
>> +++ b/riscv/.gitignore
>> @@ -0,0 +1 @@
>> +/asm-offsets-test.[hs]
>> -- 
>> 2.45.2
>>
> 
> I like this and I should probably rework stuff to replace all the _IDX
> macros in riscv/sbi-tests.h. I think we should call it sbi-asm-offsets.c,
> though, and then change the Makefile and .gitignore changes to refer to
> riscv/*-asm-offsets.h. That would allow us to keep test-specific asm-
> offsets separate and avoid the name "asm-offsets-test" or similar which,
> to me, conveys it's for testing asm-offsets.

Yes indeed, that will be clearer. I'll take care of updating the file
name as well as the gitignore in this series.

Thanks,

Clément

> 
> Thanks,
> drew