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

[Daniel Vetter]

On Thu, Aug 04, 2016 at 04:15:25PM +0200, Luc Verhaegen wrote:
> 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.
> 
> Cfr this useless, endless and ridiculous discussion: 
> http://lists.infradead.org/pipermail/linux-arm-kernel/2014-August/279071.html

simpledrm isn't a real driver, but only meant to be used to drive the
firmware framebuffer in early boot until a real driver takes over. It's a
replacement really for all the various uefi/vesa/whatever fbdev drivers.
Full reliance on the firmware very much intended.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch