Re: [PATCH v3 16/28] arm64/sve: Probe SVE capabilities and usable vector lengths

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, Oct 10, 2017 at 07:38:33PM +0100, Dave P Martin wrote:
> This patch uses the cpufeatures framework to determine common SVE
> capabilities and vector lengths, and configures the runtime SVE
> support code appropriately.
> 
> ZCR_ELx is not really a feature register, but it is convenient to
> use it as a template for recording the maximum vector length
> supported by a CPU, using the LEN field.  This field is similar to
> a feature field in that it is a contiguous bitfield for which we
> want to determine the minimum system-wide value.  This patch adds
> ZCR as a pseudo-register in cpuinfo/cpufeatures, with appropriate
> custom code to populate it.  Finding the minimum supported value of
> the LEN field is left to the cpufeatures framework in the usual
> way.
> 
> The meaning of ID_AA64ZFR0_EL1 is not architecturally defined yet,
> so for now we just require it to be zero.
> 
> Note that much of this code is dormant and SVE still won't be used
> yet, since system_supports_sve() remains hardwired to false.
> 
> Signed-off-by: Dave Martin <Dave.Martin@xxxxxxx>
> Cc: Alex Bennée <alex.bennee@xxxxxxxxxx>
> Cc: Suzuki K Poulose <Suzuki.Poulose@xxxxxxx>

Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx>
_______________________________________________
kvmarm mailing list
kvmarm@xxxxxxxxxxxxxxxxxxxxx
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm




[Index of Archives]     [Linux KVM]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux