Re: [PATCH v3 2/7] xen/arm: Add arm64 ID registers definitions

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Wed, 9 Dec 2020, Julien Grall wrote:
> Hi Bertrand,
> 
> On 09/12/2020 16:30, Bertrand Marquis wrote:
> > Add coprocessor registers definitions for all ID registers trapped
> > through the TID3 bit of HSR.
> > Those are the one that will be emulated in Xen to only publish to guests
> > the features that are supported by Xen and that are accessible to
> > guests.
> > Also define a case to catch all reserved registers that should be
> > handled as RAZ.
> > 
> > Signed-off-by: Bertrand Marquis <bertrand.marquis@xxxxxxx>
> > ---
> > Changes in V2: Rebase
> > Changes in V3:
> >    Add case definition for reserved registers.
> > 
> > ---
> >   xen/include/asm-arm/arm64/hsr.h | 66 +++++++++++++++++++++++++++++++++
> >   1 file changed, 66 insertions(+)
> > 
> > diff --git a/xen/include/asm-arm/arm64/hsr.h
> > b/xen/include/asm-arm/arm64/hsr.h
> > index ca931dd2fe..ffe0f0007e 100644
> > --- a/xen/include/asm-arm/arm64/hsr.h
> > +++ b/xen/include/asm-arm/arm64/hsr.h
> > @@ -110,6 +110,72 @@
> >   #define HSR_SYSREG_CNTP_CTL_EL0   HSR_SYSREG(3,3,c14,c2,1)
> >   #define HSR_SYSREG_CNTP_CVAL_EL0  HSR_SYSREG(3,3,c14,c2,2)
> >   +/* Those registers are used when HCR_EL2.TID3 is set */
> > +#define HSR_SYSREG_ID_PFR0_EL1    HSR_SYSREG(3,0,c0,c1,0)
> > +#define HSR_SYSREG_ID_PFR1_EL1    HSR_SYSREG(3,0,c0,c1,1)
> > +#define HSR_SYSREG_ID_PFR2_EL1    HSR_SYSREG(3,0,c0,c3,4)
> > +#define HSR_SYSREG_ID_DFR0_EL1    HSR_SYSREG(3,0,c0,c1,2)
> > +#define HSR_SYSREG_ID_DFR1_EL1    HSR_SYSREG(3,0,c0,c3,5)
> > +#define HSR_SYSREG_ID_AFR0_EL1    HSR_SYSREG(3,0,c0,c1,3)
> > +#define HSR_SYSREG_ID_MMFR0_EL1   HSR_SYSREG(3,0,c0,c1,4)
> > +#define HSR_SYSREG_ID_MMFR1_EL1   HSR_SYSREG(3,0,c0,c1,5)
> > +#define HSR_SYSREG_ID_MMFR2_EL1   HSR_SYSREG(3,0,c0,c1,6)
> > +#define HSR_SYSREG_ID_MMFR3_EL1   HSR_SYSREG(3,0,c0,c1,7)
> > +#define HSR_SYSREG_ID_MMFR4_EL1   HSR_SYSREG(3,0,c0,c2,6)
> > +#define HSR_SYSREG_ID_MMFR5_EL1   HSR_SYSREG(3,0,c0,c3,6)
> > +#define HSR_SYSREG_ID_ISAR0_EL1   HSR_SYSREG(3,0,c0,c2,0)
> > +#define HSR_SYSREG_ID_ISAR1_EL1   HSR_SYSREG(3,0,c0,c2,1)
> > +#define HSR_SYSREG_ID_ISAR2_EL1   HSR_SYSREG(3,0,c0,c2,2)
> > +#define HSR_SYSREG_ID_ISAR3_EL1   HSR_SYSREG(3,0,c0,c2,3)
> > +#define HSR_SYSREG_ID_ISAR4_EL1   HSR_SYSREG(3,0,c0,c2,4)
> > +#define HSR_SYSREG_ID_ISAR5_EL1   HSR_SYSREG(3,0,c0,c2,5)
> > +#define HSR_SYSREG_ID_ISAR6_EL1   HSR_SYSREG(3,0,c0,c2,7)
> > +#define HSR_SYSREG_MVFR0_EL1      HSR_SYSREG(3,0,c0,c3,0)
> > +#define HSR_SYSREG_MVFR1_EL1      HSR_SYSREG(3,0,c0,c3,1)
> > +#define HSR_SYSREG_MVFR2_EL1      HSR_SYSREG(3,0,c0,c3,2)
> > +
> > +#define HSR_SYSREG_ID_AA64PFR0_EL1   HSR_SYSREG(3,0,c0,c4,0)
> > +#define HSR_SYSREG_ID_AA64PFR1_EL1   HSR_SYSREG(3,0,c0,c4,1)
> > +#define HSR_SYSREG_ID_AA64DFR0_EL1   HSR_SYSREG(3,0,c0,c5,0)
> > +#define HSR_SYSREG_ID_AA64DFR1_EL1   HSR_SYSREG(3,0,c0,c5,1)
> > +#define HSR_SYSREG_ID_AA64ISAR0_EL1  HSR_SYSREG(3,0,c0,c6,0)
> > +#define HSR_SYSREG_ID_AA64ISAR1_EL1  HSR_SYSREG(3,0,c0,c6,1)
> > +#define HSR_SYSREG_ID_AA64MMFR0_EL1  HSR_SYSREG(3,0,c0,c7,0)
> > +#define HSR_SYSREG_ID_AA64MMFR1_EL1  HSR_SYSREG(3,0,c0,c7,1)
> > +#define HSR_SYSREG_ID_AA64MMFR2_EL1  HSR_SYSREG(3,0,c0,c7,2)
> > +#define HSR_SYSREG_ID_AA64AFR0_EL1   HSR_SYSREG(3,0,c0,c5,4)
> > +#define HSR_SYSREG_ID_AA64AFR1_EL1   HSR_SYSREG(3,0,c0,c5,5)
> > +#define HSR_SYSREG_ID_AA64ZFR0_EL1   HSR_SYSREG(3,0,c0,c4,4)
> > +
> > +/*
> > + * Those cases are catching all Reserved registers trapped by TID3 which
> > + * currently have no assignment.
> > + * HCR.TID3 is trapping all registers in the group 3:
> > + * Op0 == 3, op1 == 0, CRn == c0,CRm == {c1-c7}, op2 == {0-7}.
> > + */
> > +#define HSR_SYSREG_TID3_RESERVED_CASE  case HSR_SYSREG(3,0,c0,c3,3): \
> > +                                       case HSR_SYSREG(3,0,c0,c3,7): \
> > +                                       case HSR_SYSREG(3,0,c0,c4,2): \
> > +                                       case HSR_SYSREG(3,0,c0,c4,3): \
> > +                                       case HSR_SYSREG(3,0,c0,c4,5): \
> > +                                       case HSR_SYSREG(3,0,c0,c4,6): \
> > +                                       case HSR_SYSREG(3,0,c0,c4,7): \
> > +                                       case HSR_SYSREG(3,0,c0,c5,2): \
> > +                                       case HSR_SYSREG(3,0,c0,c5,3): \
> > +                                       case HSR_SYSREG(3,0,c0,c5,6): \
> > +                                       case HSR_SYSREG(3,0,c0,c5,7): \
> > +                                       case HSR_SYSREG(3,0,c0,c6,2): \
> > +                                       case HSR_SYSREG(3,0,c0,c6,3): \
> > +                                       case HSR_SYSREG(3,0,c0,c6,4): \
> > +                                       case HSR_SYSREG(3,0,c0,c6,5): \
> > +                                       case HSR_SYSREG(3,0,c0,c6,6): \
> > +                                       case HSR_SYSREG(3,0,c0,c6,7): \
> > +                                       case HSR_SYSREG(3,0,c0,c7,3): \
> > +                                       case HSR_SYSREG(3,0,c0,c7,4): \
> > +                                       case HSR_SYSREG(3,0,c0,c7,5): \
> > +                                       case HSR_SYSREG(3,0,c0,c7,6): \
> > +                                       case HSR_SYSREG(3,0,c0,c7,7)
> 
> I don't like the idea to define the list of case in a header that is used by
> multiple source. Please define it directly in the source file that use it.

At that point it might be best to open-coding it in do_sysreg? I mean no
#define at all.