Re: [PATCH 0/2] drm: add SimpleDRM driver

Noralf Trønnes
2016-08-04T16:59:05Z

Den 04.08.2016 16:15, skrev Luc Verhaegen:
> On Thu, Aug 04, 2016 at 04:03:18PM +0200, Noralf Trønnes wrote:
>> I have tested simpledrm on a Raspberry Pi B+ with U-boot setting up the
>> framebuffer and producing this node:
>>
>> framebuffer@1e887000 {
>> compatible = "simple-framebuffer";
>> reg = <0x1e887000 0x36c600>;
>> format = "r5g6b5";
>> width = <1824>;
>> height = <984>;
>> stride = <3648>;
>> status = "okay";
>> };
>>
>> I have only tested with fbcon and modetest (XR24,RG16).
> Please do not make the same mistake as simplefb in making this purely a
> rpifb. Know that you will need some power and clock management for
> properly free devices that do not depend on a binary only RTOS which
> does _everything_ behind our backs.

I didn't read the binding document[1], which I should have done.
If simpledrm claims to be compatible with simple-framebuffer I assume it
should support the entire binding doc which includes clocks, regulators
and having the node under /chosen.
I will lift the necessary code from simplefb.c and put it in the next
version.

The binding doc also mentions an optional display phandle property, but I
can't find any reference to this in simplefb.c.

Noralf.

[1] Documentation/devicetree/bindings/display/simple-framebuffer.txt