RE: [PATCH v3 35/36] net/wan: make FSL_UCC_HDLC explicitly depend on PPC32

[Qiang Zhao]

On 01/11/2019 23:31, Rasmus Villemoes wrote :


> -----Original Message-----
> From: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
> Sent: 2019å11æ4æ 16:38
> To: Leo Li <leoyang.li@xxxxxxx>; Christophe Leroy <christophe.leroy@xxxxxx>;
> Qiang Zhao <qiang.zhao@xxxxxxx>
> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx; Scott Wood <oss@xxxxxxxxxxxx>;
> netdev@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v3 35/36] net/wan: make FSL_UCC_HDLC explicitly depend
> on PPC32
> 
> On 01/11/2019 23.31, Leo Li wrote:
> >
> >
> >> -----Original Message-----
> >> From: Christophe Leroy <christophe.leroy@xxxxxx>
> >> Sent: Friday, November 1, 2019 11:30 AM
> >> To: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>; Qiang Zhao
> >> <qiang.zhao@xxxxxxx>; Leo Li <leoyang.li@xxxxxxx>
> >> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx;
> >> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> >> linux-kernel@xxxxxxxxxxxxxxx; Scott Wood <oss@xxxxxxxxxxxx>;
> >> netdev@xxxxxxxxxxxxxxx
> >> Subject: Re: [PATCH v3 35/36] net/wan: make FSL_UCC_HDLC explicitly
> >> depend on PPC32
> >>
> >>
> >>
> >> Le 01/11/2019 Ã 13:42, Rasmus Villemoes a ÃcritÂ:
> >>> Currently, FSL_UCC_HDLC depends on QUICC_ENGINE, which in turn
> >> depends
> >>> on PPC32. As preparation for removing the latter and thus allowing
> >>> the core QE code to be built for other architectures, make
> >>> FSL_UCC_HDLC explicitly depend on PPC32.
> >>
> >> Is that really powerpc specific ? Can't the ARM QE perform HDLC on UCC ?
> 
> I think the driver would build on ARM. Whether it works I don't know. I know it
> does not build on 64 bit hosts (see kbuild report for v2,23/23).
> 
> > No.  Actually the HDLC and TDM are the major reason to integrate a QE on
> the ARM based Layerscape SoCs.
> 
> [citation needed].
> 
> > Since Rasmus doesn't have the hardware to test this feature Qiang Zhao
> probably can help verify the functionality of TDM and we can drop this patch.
> 
> No, this patch cannot be dropped. Please see the kbuild complaints for
> v2,23/23 about use of IS_ERR_VALUE on not-sizeof(long) entities. I see kbuild
> has complained about the same thing for v3 since apparently the same thing
> appears in ucc_slow.c. So I'll fix that.
> 
> Moreover, as you say and know, I do not have the hardware to test it, so I'm
> not going to even attempt to fix up fsl_ucc_hdlc.c. If Qiang Zhao or somebody
> else can verify that it works just fine on ARM and fixes the allmodconfig
> problem(s), he/she is more than welcome to sign off on a patch that removes
> the CONFIG_PPC32 dependency or replaces it with something else.
> 

I tested your v3 patches on ls1043ardb which is arm64 for fsl_ucc_hdlc, it can work,
Only it will put a compile warning, I also made a patch to fix it.
I can send a patch to remove PPC32 dependency when I send my patch to support ARM64.
Or I add my patch in your patchset.

Best Regards
Qiang Zhao