[lkml]   [2021]   [Sep]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH] crypto: caam: disable pkc for non-E SoCs
On 9/16/2021 1:03 AM, Michael Walle wrote:
> On newer CAAM versions, not all accelerators are disabled if the SoC is
> a non-E variant. While the driver checks most of the modules for
> availability, there is one - PKHA - which sticks out. On non-E variants
Currently there's no dedicated support for "partially disabled" non-E
(export-controlled) parts in Linux kernel caam driver(s).

Up until recently firmware (U-boot) was deleting the "crypto" DT node
for all non-E parts [1].
Modifying the f/w indeed triggers changes across the s/w stack.

Since you are modifying only the caam code handling PKHA, is it correct
to assume that everything else is working fine?
For example: is the number of AES accelerators (AESA_VERSION[AESA_NUM])
being reported as 0 on non-E parts?

> it is still reported as available, that is the number of instances is
> non-zero, but it has limited functionality. In particular it doesn't
> support encryption and decryption, but just signing and verifying. This
> is indicated by a bit in the PKHA_MISC field. Take this bit into account
> if we are checking for availablitly.
typo: ^ availability
> This will the following error:
> [ 8.167817] caam_jr 8020000.jr: 20000b0f: CCB: desc idx 11: : Invalid CHA selected.
> Tested on an NXP LS1028A (non-E) SoC.
Unfortunately I don't have a non-E part to test on.


4eecc6f1a104 ("armv8: layerscape: don't remove crypto node if just partially disabled")

 \ /
  Last update: 2021-09-22 17:53    [W:0.108 / U:0.416 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site