Re: [PATCH 0/1] x86: Quark: Enable correct cache size/type reporting

[Ingo Molnar <mingo@kernel.org>]

* Bryan O'Donoghue <pure.logic@nexus-software.ie> wrote:

> Quark X1000 lacks cpuid(4). It has cpuid(2) but returns no cache
> descriptors we can work with i.e. cpuid(2) returns
> eax=0x00000001 ebx=0x00000000 ecx=0x00000000 edx=0x00000000
> 
> Quark X1000 contains a 16k 4-way set associative unified L1 cache
> with 256 sets
> 
> This patch emulates cpuid(4) in a similar way to other x86
> processors like AMDs which don't support cpuid(4). The Quark code
> is based on the existing AMD code.
> 
> Before applying this patch we see
> / # cat /proc/cpuinfo
> processor       : 0
> vendor_id       : GenuineIntel
> cpu family      : 5
> model           : 9
> model name      : 05/09
> stepping        : 0
> cpu MHz         : 399.076
> cache size      : 0 KB
> fdiv_bug        : no
> f00f_bug        : yes
> coma_bug        : no
> fpu             : yes
> fpu_exception   : yes
> cpuid level     : 7
> wp              : yes
> flags           : fpu vme pse tsc msr pae cx8 apic pbe nx smep
> bugs            : f00f
> bogomips        : 798.15
> clflush size    : 32
> cache_alignment : 32
> address sizes   : 32 bits physical, 32 bits virtual
> power management:
> 
> With no entries in
> /sys/devices/system/cpu/cpu0/cache/*/*
> 
> After applying this patch we see
> / # cat /proc/cpuinfo
> processor       : 0
> vendor_id       : GenuineIntel
> cpu family      : 5
> model           : 9
> model name      : 05/09
> stepping        : 0
> cpu MHz         : 399.076
> cache size      : 16 KB
> fdiv_bug        : no
> f00f_bug        : yes
> coma_bug        : no
> fpu             : yes
> fpu_exception   : yes
> cpuid level     : 7
> wp              : yes
> flags           : fpu vme pse tsc msr pae cx8 apic pbe nx smep
> bugs            : f00f
> bogomips        : 798.15
> clflush size    : 32
> cache_alignment : 32
> address sizes   : 32 bits physical, 32 bits virtual
> power management:
> 
> / # ls /sys/devices/system/cpu/cpu0/cache/*/*
> /sys/devices/system/cpu/cpu0/cache/index0/coherency_line_size
> /sys/devices/system/cpu/cpu0/cache/index0/level
> /sys/devices/system/cpu/cpu0/cache/index0/number_of_sets
> /sys/devices/system/cpu/cpu0/cache/index0/physical_line_partition
> /sys/devices/system/cpu/cpu0/cache/index0/shared_cpu_list
> /sys/devices/system/cpu/cpu0/cache/index0/shared_cpu_map
> /sys/devices/system/cpu/cpu0/cache/index0/size
> /sys/devices/system/cpu/cpu0/cache/index0/type
> /sys/devices/system/cpu/cpu0/cache/index0/ways_of_associativity
> 
> / # for i in /sys/devices/system/cpu/cpu0/cache/*/* ; do echo -n "`basename $i`:
>  " && cat $i ; done
> coherency_line_size: 16
> level: 1
> number_of_sets: 256
> physical_line_partition: 1
> shared_cpu_list:
> shared_cpu_map: 0
> size: 16K
> type: Unified
> ways_of_associativity: 4

So why isn't this larger changelog part of the patch? It's all 
useful information.

Thanks,

	Ingo