Re: [PATCH v2 4/7] xen/arm: Add handler for ID registers on arm64

[Volodymyr Babchuk <Volodymyr_Babchuk@xxxxxxxx>]

Bertrand Marquis writes:

> Add vsysreg emulation for registers trapped when TID3 bit is activated
> in HSR.
> The emulation is returning the value stored in cpuinfo_guest structure
> for most values and the hardware value for registers not stored in the
> structure (those are mostly registers existing only as a provision for
> feature use but who have no definition right now).

I can't see the code that returns values for the registers not stored in
the guest_cpuinfo. Perhaps you need to update the commit description?

> Signed-off-by: Bertrand Marquis <bertrand.marquis@xxxxxxx>
> ---
> Changes in V2: rebase
> ---
>  xen/arch/arm/arm64/vsysreg.c | 49 ++++++++++++++++++++++++++++++++++++
>  1 file changed, 49 insertions(+)
>
> diff --git a/xen/arch/arm/arm64/vsysreg.c b/xen/arch/arm/arm64/vsysreg.c
> index 8a85507d9d..970ef51603 100644
> --- a/xen/arch/arm/arm64/vsysreg.c
> +++ b/xen/arch/arm/arm64/vsysreg.c
> @@ -69,6 +69,14 @@ TVM_REG(CONTEXTIDR_EL1)
>          break;                                                          \
>      }
>  
> +/* Macro to generate easily case for ID co-processor emulation */
> +#define GENERATE_TID3_INFO(reg,field,offset)                            \
> +    case HSR_SYSREG_##reg:                                              \
> +    {                                                                   \
> +        return handle_ro_read_val(regs, regidx, hsr.sysreg.read, hsr,   \
> +                          1, guest_cpuinfo.field.bits[offset]);         \
> +    }
> +
>  void do_sysreg(struct cpu_user_regs *regs,
>                 const union hsr hsr)
>  {
> @@ -259,6 +267,47 @@ void do_sysreg(struct cpu_user_regs *regs,
>           */
>          return handle_raz_wi(regs, regidx, hsr.sysreg.read, hsr, 1);
>  
> +    /*
> +     * HCR_EL2.TID3
> +     *
> +     * This is trapping most Identification registers used by a guest
> +     * to identify the processor features
> +     */
> +    GENERATE_TID3_INFO(ID_PFR0_EL1, pfr32, 0)
> +    GENERATE_TID3_INFO(ID_PFR1_EL1, pfr32, 1)
> +    GENERATE_TID3_INFO(ID_PFR2_EL1, pfr32, 2)
> +    GENERATE_TID3_INFO(ID_DFR0_EL1, dbg32, 0)
> +    GENERATE_TID3_INFO(ID_DFR1_EL1, dbg32, 1)
> +    GENERATE_TID3_INFO(ID_AFR0_EL1, aux32, 0)
> +    GENERATE_TID3_INFO(ID_MMFR0_EL1, mm32, 0)
> +    GENERATE_TID3_INFO(ID_MMFR1_EL1, mm32, 1)
> +    GENERATE_TID3_INFO(ID_MMFR2_EL1, mm32, 2)
> +    GENERATE_TID3_INFO(ID_MMFR3_EL1, mm32, 3)
> +    GENERATE_TID3_INFO(ID_MMFR4_EL1, mm32, 4)
> +    GENERATE_TID3_INFO(ID_MMFR5_EL1, mm32, 5)
> +    GENERATE_TID3_INFO(ID_ISAR0_EL1, isa32, 0)
> +    GENERATE_TID3_INFO(ID_ISAR1_EL1, isa32, 1)
> +    GENERATE_TID3_INFO(ID_ISAR2_EL1, isa32, 2)
> +    GENERATE_TID3_INFO(ID_ISAR3_EL1, isa32, 3)
> +    GENERATE_TID3_INFO(ID_ISAR4_EL1, isa32, 4)
> +    GENERATE_TID3_INFO(ID_ISAR5_EL1, isa32, 5)
> +    GENERATE_TID3_INFO(ID_ISAR6_EL1, isa32, 6)
> +    GENERATE_TID3_INFO(MVFR0_EL1, mvfr, 0)
> +    GENERATE_TID3_INFO(MVFR1_EL1, mvfr, 1)
> +    GENERATE_TID3_INFO(MVFR2_EL1, mvfr, 2)
> +    GENERATE_TID3_INFO(ID_AA64PFR0_EL1, pfr64, 0)
> +    GENERATE_TID3_INFO(ID_AA64PFR1_EL1, pfr64, 1)
> +    GENERATE_TID3_INFO(ID_AA64DFR0_EL1, dbg64, 0)
> +    GENERATE_TID3_INFO(ID_AA64DFR1_EL1, dbg64, 1)
> +    GENERATE_TID3_INFO(ID_AA64ISAR0_EL1, isa64, 0)
> +    GENERATE_TID3_INFO(ID_AA64ISAR1_EL1, isa64, 1)
> +    GENERATE_TID3_INFO(ID_AA64MMFR0_EL1, mm64, 0)
> +    GENERATE_TID3_INFO(ID_AA64MMFR1_EL1, mm64, 1)
> +    GENERATE_TID3_INFO(ID_AA64MMFR2_EL1, mm64, 2)
> +    GENERATE_TID3_INFO(ID_AA64AFR0_EL1, aux64, 0)
> +    GENERATE_TID3_INFO(ID_AA64AFR1_EL1, aux64, 1)
> +    GENERATE_TID3_INFO(ID_AA64ZFR0_EL1, zfr64, 0)
> +
>      /*
>       * HCR_EL2.TIDCP
>       *


-- 
Volodymyr Babchuk at EPAM