[PATCH v3 00/19] Add Freescale i.MX8qxp Display Controller support

[Dmitry Baryshkov]

On Sun, Jul 28, 2024 at 03:10:21AM GMT, Sui Jingfeng wrote:
> Hi,
> 
> On 7/28/24 00:39, Dmitry Baryshkov wrote:
> > > Hi,
> > > 
> > > This patch series aims to add Freescale i.MX8qxp Display Controller support.
> > > 
> > > The controller is comprised of three main components that include a blit
> > > engine for 2D graphics accelerations, display controller for display output
> > > processing, as well as a command sequencer.
> > > 
> > > Previous patch series attempts to do that can be found at:
> > > https://patchwork.freedesktop.org/series/84524/
> > > 
> > > This series addresses Maxime's comments on the previous one:
> > > a. Split the display controller into multiple internal devices.
> > >     1) List display engine, pixel engine, interrupt controller and more as the
> > >        controller's child devices.
> > >     2) List display engine and pixel engine's processing units as their child
> > >        devices.
> > > 
> > > b. Add minimal feature support.
> > >     Only support two display pipelines with primary planes with XR24 fb,
> > >     backed by two fetchunits.  No fetchunit dynamic allocation logic(to be done
> > >     when necessary).
> > > 
> > > c. Use drm_dev_{enter, exit}().
> > > 
> > > Since this series changes a lot comparing to the previous one, I choose to
> > > send it with a new patch series, not a new version.
> > I'm sorry, I have started reviewing v2 without noticing that there is a
> > v3 already.
> > 
> > Let me summarize my comments:
> > 
> > - You are using OF aliases. Are they documented and acked by DT
> >    maintainers?
> > 
> > - I generally feel that the use of so many small devices to declare
> >    functional blocks is an abuse of the DT. Please consider creating
> >    _small_ units from the driver code directly rather than going throught
> >    the components.
> 
> Well, I really don't think so. I don't agree.
> 
> I have checked the DTSpec[1] before type, the spec isn't define how
> many is considered to be "many", and the spec isn't define to what
> extent is think to be "small" as well.

Yeah. However _usually_ we are not defining DT devices for sub-device
components. So at least such decisions ought to be described and
explained in the cover letter.

> 
> [1]
> https://github.com/devicetree-org/devicetree-specification/releases/tag/v0.4

-- 
With best wishes
Dmitry