[GIT PULL] Allwinner drivers changes for 4.2

[Maxime Ripard]

On Wed, May 13, 2015 at 12:30:39PM +0200, Arnd Bergmann wrote:
> > > Sorry I hadn't looked at the new driver before, but I did now and need a little
> > > clarification. It seems to me that the device should be compatible with the
> > > generic DT binding we have in Documentation/devicetree/bindings/misc/sram.txt,
> > > and use more generic code. At least I can't see much in here that is really sunxi
> > > specific.
> > >
> > > Were you not aware of that generic binding, or did you have a good reason
> > > not to use it?
> > 
> > I asked myself the same question, and I don't really think that this
> > would be wise, since that in order to be accessible by the CPU it has
> > to be mapped to it through this driver.
> > 
> > I felt like this alone justify a new compatible, even though we might
> > end up using the same driver.
> 
> Have you discussed this with Heiko?

No, I didn't.

We don't need to use his driver, there was no point about discussing
with him about anything.

> > > In the latter case, please document that in the patch description
> > > (after replying here).
> > 
> > Ok.
> > 
> > > One small bug I found in the DT binding: the main DT node is lacking
> > > a "ranges" property.
> > 
> > Which DT node are you talking about ?
> 
> I was referring to the ranges in this:
> 
> +soc at 01c00000 {
> +       compatible = "simple-bus";
> +       #address-cells = <1>;
> +       #size-cells = <1>;
> +       ranges;
> +
> +       sram at 00000000 {
> +               compatible = "allwinner,sun4i-a10-sram";
> +               reg = <0x00000000 0x4000>;
> +               allwinner,sram-name = "A1";
> +       };
> 
> but I now think I was misreading it, and the problem is different:
> Rather than having separate devices for parts of the SRAM, you
> are actually missing a node for the SRAM physical window. I think
> the individual SRAM pieces should be nodes below one that describes
> all of the SRAM, as we do in 
> Documentation/devicetree/bindings/misc/sram.txt

These are physically separate SRAM, used for different purposes, by
different devices.

Since when in the DT different instances of the same IP should be
represented in a single node?

And again, this patch is really not about "Simple IO memory regions to
be managed by the genalloc API". We have no use for these SRAMs, and
just want them to be mapped to the device, so the CPU won't even have
access to them for most of them.

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: Digital signature
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20150513/b6bb98f8/attachment.sig>