Re: [PATCH 3/7] drm/vc4: Add KMS support for Raspberry Pi.

On 08/12/2015 06:56 PM, Eric Anholt wrote:

This is the start of a full VC4 driver. Right now this just supports configuring the display using a pre-existing video mode (because changing the pixel clock isn't available yet, and doesn't work when it is). However, this is enough for fbcon and bringing up X using xf86-video-modesetting.

diff --git a/drivers/gpu/drm/vc4/Kconfig b/drivers/gpu/drm/vc4/Kconfig

+config DRM_VC4

• tristate "Broadcom VC4 Graphics"

• help

•  Choose this option if you have a system that has a Broadcom
  

•  VC4 GPU, such as the Raspberry Pi or other BCM2708/BCM2835.
  

•  This driver requires that "avoid_warnings=2" be present in
  

•  the config.txt for the firmware, to keep it from smashing
  

•  our display setup.
  

The need for "avoid_warnings=2" seems like it will trip people up. I don't think it's in any config.txt I've seen. Can you expand more on that?