Re: [PATCH V2 3/5] selftests/powerpc: Add NX-GZIP engine compress testcase

[Michael Ellerman <mpe@ellerman.id.au>]

Daniel Axtens <dja@axtens.net> writes:
> Raphael Moreira Zinsly <rzinsly@linux.ibm.com> writes:
>
>> Add a compression testcase for the powerpc NX-GZIP engine.
>>
>> Signed-off-by: Bulent Abali <abali@us.ibm.com>
>> Signed-off-by: Raphael Moreira Zinsly <rzinsly@linux.ibm.com>
...
>> diff --git a/tools/testing/selftests/powerpc/nx-gzip/gzip_vas.c b/tools/testing/selftests/powerpc/nx-gzip/gzip_vas.c
>> new file mode 100644
>> index 000000000000..d28e1efb527b
>> --- /dev/null
>> +++ b/tools/testing/selftests/powerpc/nx-gzip/gzip_vas.c
>> @@ -0,0 +1,259 @@
>> +// SPDX-License-Identifier: GPL-2.0-or-later
>> +
>> +/* Copyright 2020 IBM Corp.
>> + *
>> + * Author: Bulent Abali <abali@us.ibm.com>
>> + *
>> + */
>> +#include <stdio.h>
>> +#include <stdlib.h>
>> +#include <string.h>
>> +#include <unistd.h>
>> +#include <stdint.h>
>> +#include <sys/types.h>
>> +#include <sys/stat.h>
>> +#include <sys/time.h>
>> +#include <sys/fcntl.h>
>> +#include <sys/mman.h>
>> +#include <endian.h>
>> +#include <bits/endian.h>
>> +#include <sys/ioctl.h>
>> +#include <assert.h>
>> +#include <errno.h>
>> +#include <signal.h>
>> +#include "nx-gzip.h"
>> +#include "nx.h"
>> +#include "copy-paste.h"
>> +#include "nxu.h"
>> +#include "nx_dbg.h"
>> +#include <sys/platform/ppc.h>
>> +
>> +#define barrier()
>> +#define hwsync()    ({ asm volatile("hwsync" ::: "memory"); })
>
> This doesn't compile on the clang version I tried as it doesn't
> recognise 'hwsync'.

What assembler are you using? I guess the LLVM one?

Can you try with -fno-integrated-as ?

> Does asm volatile("sync" ::: "memory");
> do the same thing? That is recognised by clang, but I don't know if
> dropping the hw prefix matters!

It shouldn't matter.

But you can just try it and look at the generated code to be sure, you
should get 0x7c0004ac.

cheers