Re: [PATCH 0/4] arm64: wire CRC32 instructions into core crc32 routines
From: Ard Biesheuvel
Date: Mon Aug 27 2018 - 11:18:36 EST
On 27 August 2018 at 16:53, Theodore Y. Ts'o <tytso@xxxxxxx> wrote:
> On Mon, Aug 27, 2018 at 01:02:41PM +0200, Ard Biesheuvel wrote:
>> While this is not known to cause performance issues, calling a table based
>> time variant implementation with a non-negligible D-cache footprint (8 KB)
>> is wasteful in any case, and now that the crc32 instructions have been made
>> mandatory in the architecture, let's wire them up into the core crc routines.
>
> Stupid question --- are there any arm64 SOC's out there which do *not*
> have the crc32 instructions? Presumably there won't be in the future,
> because it's now mandatory --- but where there any in the past?
>
Yes, the APM Xgene for instance.