Re: [Xen-devel] [PATCH 2/4] arm: processor: add ccknownpass field into hsr_cond union

[Julien Grall <julien.grall@xxxxxxx>]

On 07/28/2017 09:31 PM, Julien Grall wrote:
> Hi,
>
> On 07/28/2017 08:43 PM, Volodymyr Babchuk wrote:
> > On ARMv8, one of conditional exceptions (SMC that originates
> > from aarch32 state) have extra field in HCR.ISS encoding:
> >
> > CCKNOWNPASS, bit [19]
> > Indicates whether the instruction might have failed its condition
> > code check.
> >     0 - The instruction was unconditional, or was conditional and
> >     passed  its condition code check.
> >     1 - The instruction was conditional, and might have failed its
> >     condition code check.
> Please mention the ARM ARM version and paragraph.
>
> > Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@xxxxxxxx>
> > ---
> >   xen/include/asm-arm/processor.h | 3 ++-
> >   1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/xen/include/asm-arm/processor.h 
> > b/xen/include/asm-arm/processor.h
> > index f640d54..0131e66 100644
> > --- a/xen/include/asm-arm/processor.h
> > +++ b/xen/include/asm-arm/processor.h
> > @@ -434,7 +434,8 @@ union hsr {
> >       /* Common to all conditional exception classes (0x0N, except 
> > 0x00). */
> When I read this comment, I understand that hsr_cond contains common 
> bits for all condition exception. However, with your changes this is not 
> true at all.
To complete here. I think you should directly use hsr.smc.ccknownpass 
rather than hsr.cond in patch #4 given that this field is SMC specific.
> >       struct hsr_cond {
> > -        unsigned long res0:20;  /* Reserved */
> > +        unsigned long res0:19;  /* Reserved */
> > +        unsigned long ccknownpass:1; /* Instruction passed 
> > conditional check */
> >           unsigned long cc:4;    /* Condition Code */
> >           unsigned long ccvalid:1;/* CC Valid */
> >           unsigned long len:1;   /* Instruction length */
> Cheers,

--
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel