Re: [PATCH 6/6] x86/apic: Convert the TSC deadline errata table to X86_MATCH_*()

[Jan Beulich <jbeulich@xxxxxxxx>]

On 16.07.2025 19:31, Andrew Cooper wrote:
> --- a/xen/arch/x86/apic.c
> +++ b/xen/arch/x86/apic.c
> @@ -1051,64 +1051,32 @@ static void setup_APIC_timer(void)
>      local_irq_restore(flags);
>  }
>  
> -#define DEADLINE_MODEL_MATCH(m, fr) \
> -    { .vendor = X86_VENDOR_INTEL, .family = 6, .model = (m), \
> -      .feature = X86_FEATURE_TSC_DEADLINE, \
> -      .driver_data = (void *)(unsigned long)(fr) }
> +static const struct x86_cpu_id __initconst deadline_match[] = {
> +    X86_MATCH_VFMS(INTEL_HASWELL_X,   0x2, 0x3a), /* EP */
> +    X86_MATCH_VFMS(INTEL_HASWELL_X,   0x4, 0x0f), /* EX */
>  
> -static unsigned int __init hsx_deadline_rev(void)
> -{
> -    switch ( boot_cpu_data.x86_mask )
> -    {
> -    case 0x02: return 0x3a; /* EP */
> -    case 0x04: return 0x0f; /* EX */
> -    }
> +    X86_MATCH_VFM (INTEL_BROADWELL_X,      0x0b000020),
>  
> -    return ~0U;
> -}
> +    X86_MATCH_VFMS(INTEL_BROADWELL_D, 0x2, 0x00000011),
> +    X86_MATCH_VFMS(INTEL_BROADWELL_D, 0x3, 0x0700000e),
> +    X86_MATCH_VFMS(INTEL_BROADWELL_D, 0x4, 0x0f00000c),
> +    X86_MATCH_VFMS(INTEL_BROADWELL_D, 0x5, 0x0e000003),

Hmm, actually - why are Broadwell and ...

> -static unsigned int __init bdx_deadline_rev(void)
> -{
> -    switch ( boot_cpu_data.x86_mask )
> -    {
> -    case 0x02: return 0x00000011;
> -    case 0x03: return 0x0700000e;
> -    case 0x04: return 0x0f00000c;
> -    case 0x05: return 0x0e000003;
> -    }
> +    X86_MATCH_VFMS(INTEL_SKYLAKE_X,   0x3, 0x01000136),
> +    X86_MATCH_VFMS(INTEL_SKYLAKE_X,   0x4, 0x02000014),

... Skylake each split ...

> -    return ~0U;
> -}
> +    X86_MATCH_VFM (INTEL_HASWELL,          0x22),
> +    X86_MATCH_VFM (INTEL_HASWELL_L,        0x20),
> +    X86_MATCH_VFM (INTEL_HASWELL_G,        0x17),
>  
> -static unsigned int __init skx_deadline_rev(void)
> -{
> -    switch ( boot_cpu_data.x86_mask )
> -    {
> -    case 0x00 ... 0x02: return ~0U;
> -    case 0x03: return 0x01000136;
> -    case 0x04: return 0x02000014;
> -    }
> -
> -    return 0;
> -}
> -
> -static const struct x86_cpu_id __initconstrel deadline_match[] = {
> -    DEADLINE_MODEL_MATCH(0x3c, 0x22),             /* Haswell */
> -    DEADLINE_MODEL_MATCH(0x3f, hsx_deadline_rev), /* Haswell EP/EX */
> -    DEADLINE_MODEL_MATCH(0x45, 0x20),             /* Haswell D */
> -    DEADLINE_MODEL_MATCH(0x46, 0x17),             /* Haswell H */
> +    X86_MATCH_VFM (INTEL_BROADWELL,        0x25),
> +    X86_MATCH_VFM (INTEL_BROADWELL_G,      0x17),

... into disjoint groups (continuing ...

> -    DEADLINE_MODEL_MATCH(0x3d, 0x25),             /* Broadwell */
> -    DEADLINE_MODEL_MATCH(0x47, 0x17),             /* Broadwell H */
> -    DEADLINE_MODEL_MATCH(0x4f, 0x0b000020),       /* Broadwell EP/EX */
> -    DEADLINE_MODEL_MATCH(0x56, bdx_deadline_rev), /* Broadwell D */
> +    X86_MATCH_VFM (INTEL_SKYLAKE_L,        0xb2),
> +    X86_MATCH_VFM (INTEL_SKYLAKE,          0xb2),

... here)? The patch already isn't overly straightforward to review without
that.

Jan