Re: [PATCH] xen/arm: gic-v3: Implement correctly the callback send_SGI

[Ian Campbell <ian.campbell@citrix.com>]

On Fri, 2015-05-08 at 17:55 +0100, Julien Grall wrote:
> Hi Ian,
> 
> On 08/05/15 16:51, Ian Campbell wrote:
> > On Fri, 2015-05-08 at 15:34 +0100, Julien Grall wrote:
> >> On 08/05/15 15:01, Ian Campbell wrote:
> >>> I think you should just cast to uint64_t and WRITE_SYSREG64.
> >>
> >> Right, I blindly re-use the WRITE_SYSREG as it was done on the previous
> >> implementation.
> >>
> >> Although, the gic-v3 code seems to always use {READ,WRITE}_SYSREG. This
> >> seems wrong too. I will send a patch for replace the calls by the the
> >> 64-bit version.
> > 
> > Thanks (although do make sure each register really is 64-bit...)
> 
> I looked more closely to the call of READ_SYSREG/WRITE_SYSREG in the
> GICv3 code. They are use for:
> 	- ICH_LR<n>: 64-bit on aarch64 and 32-bit on aarch32. Although, for
> completion we would have to read ICH_LRC<n> for aarch32.
> 	- ICC_SGIR1_EL1: 64-bit on both aarch64 and aarch32.
> 
> So the former is valid although it won't work correctly if someone
> decide to use GICv3 on AArch32.

Right, you would need a #define in cpregs.h for the arm32 case.

>  Although, I expect seen more issue than
> this one. So I will ignore it.
> 
> I will take care of the later in the new version of this patch.

Thanks,

Ian.