Re: [PATCH V5 03/21] crypto: hisilicon/qm: Fix to enable build with RISC-V clang

[Sunil V L <sunilvl@ventanamicro.com>]

On Tue, May 09, 2023 at 10:17:45AM +0800, Herbert Xu wrote:
> On Mon, May 08, 2023 at 05:22:19PM +0530, Sunil V L wrote:
> > With CONFIG_ACPI enabled for RISC-V, this driver gets enabled in
> > allmodconfig build. However, build fails with clang and below
> > error is seen.
> > 
> > drivers/crypto/hisilicon/qm.c:627:10: error: invalid output constraint '+Q' in asm
> >                        "+Q" (*((char __iomem *)fun_base))
> >                        ^
> > This is expected error with clang due to the way it is designed.
> > 
> > To fix this issue, move arm64 assembly code under #if.
> > 
> > Link: https://github.com/ClangBuiltLinux/linux/issues/999
> > Signed-off-by: Nathan Chancellor <nathan@kernel.org>
> > [sunilvl@ventanamicro.com: Moved tmp0 and tmp1 into the #if]
> > Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
> > ---
> >  drivers/crypto/hisilicon/qm.c | 13 +++++++------
> >  1 file changed, 7 insertions(+), 6 deletions(-)
> > 
> > diff --git a/drivers/crypto/hisilicon/qm.c b/drivers/crypto/hisilicon/qm.c
> > index ad0c042b5e66..2eaeaac2e246 100644
> > --- a/drivers/crypto/hisilicon/qm.c
> > +++ b/drivers/crypto/hisilicon/qm.c
> > @@ -610,13 +610,9 @@ EXPORT_SYMBOL_GPL(hisi_qm_wait_mb_ready);
> >  static void qm_mb_write(struct hisi_qm *qm, const void *src)
> >  {
> >  	void __iomem *fun_base = qm->io_base + QM_MB_CMD_SEND_BASE;
> > -	unsigned long tmp0 = 0, tmp1 = 0;
> >  
> > -	if (!IS_ENABLED(CONFIG_ARM64)) {
> > -		memcpy_toio(fun_base, src, 16);
> > -		dma_wmb();
> > -		return;
> > -	}
> 
> Please leave this bit as it stands.
> 
> > +#if IS_ENABLED(CONFIG_ARM64)
> > +	unsigned long tmp0 = 0, tmp1 = 0;
> >  
> >  	asm volatile("ldp %0, %1, %3\n"
> >  		     "stp %0, %1, %2\n"
> > @@ -626,6 +622,11 @@ static void qm_mb_write(struct hisi_qm *qm, const void *src)
> >  		       "+Q" (*((char __iomem *)fun_base))
> >  		     : "Q" (*((char *)src))
> >  		     : "memory");
> 
> And simply add the ifdef around the assembly.
> 
Sure, Herbert.

Thanks!
Sunil