Re: [PATCH v3 16/16] ARM: marvell/dt: add crypto node to kirkwood dtsi

Jason, Gregory,

On Mon, 25 May 2015 16:46:51 +0000
Jason Cooper [off-list ref] wrote:

On Mon, May 25, 2015 at 05:39:13PM +0200, Gregory CLEMENT wrote:

quoted

Hi Boris, Arnaud,

On 22/05/2015 15:34, Boris Brezillon wrote:

quoted

From: Arnaud Ebalard <redacted>

Add crypto related nodes to kirkwood.dtsi.

Here you use a new compatible string but with an old binding
to let the user chose between the old and the new driver. Am I right?

That was not the intention, but you're right, that's exactly what's
happening here.

I thought we had settled on the user choosing by module load/ which driver is
compiled in?  The DT should be describing the hardware, not which driver the
user chooses to use.

Right, but I didn't want to add new compatible strings to the old
driver in the first place, neither I wanted to support the new way of
defining/referencing the crypto SRAMs.
ITOH, if we want to benefit from the TDMA optimization on Kirkwood SoCs,
we have to add a new compatible (unlike Orion SoCs, Kirkwood ones embed
a TDMA engine).

This leaves the following solutions:
 - avoid changing the compatible in existing orion and kirkwood dtsi
   files
 - adding kirkwood compatible string support to the existing CESA
   driver (and I think supporting the new approach to retrieve SRAM
   memory region would make sense too)

Best Regards,

Boris
-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com