On Mon, May 25, 2015 at 08:43:02PM +0200, Boris Brezillon wrote: > Jason, Gregory, > > On Mon, 25 May 2015 16:46:51 +0000 > Jason Cooper <jason@xxxxxxxxxxxxxx> wrote: > > > On Mon, May 25, 2015 at 05:39:13PM +0200, Gregory CLEMENT wrote: > > > Hi Boris, Arnaud, > > > > > > On 22/05/2015 15:34, Boris Brezillon wrote: > > > > From: Arnaud Ebalard <arno@xxxxxxxxxxxx> > > > > > > > > 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). Ah, there's the HW difference I must have missed in my previous thousand-foot overview scans :-/ So "marvell,orion-crypto" matches IP blocks without the TDMA engine, "marvell,kirkwood-crypto" matches IP blocks *with* the TDMA engine. > This leaves the following solutions: > - avoid changing the compatible in existing orion and kirkwood dtsi > files no, in light of the above HW difference, it makes sense to change these. > - 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) Or, old driver matches "marvell,orion-crypto", and the new driver matches either compatible string. If dt has "marvell,kirkwood-crypto" then new driver enables TDMA with the provided properties. We then update the dtsi for all but orion to "marvell,kirkwood-crypto". This may be what you are already doing. If so, please ignore my rambling. ;-) thx, Jason. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
