Re: [RFC 0/1] drm/pl111: Initial drm/kms driver for pl111

On Fri, Jul 26, 2013 at 10:14 AM, Russell King - ARM Linux
[off-list ref] wrote:

On Thu, Jul 25, 2013 at 02:21:59PM -0400, Rob Clark wrote:

quoted

On Thu, Jul 25, 2013 at 1:17 PM,  [off-list ref] wrote:

quoted

Known issues:
 * It uses KDS. We intend to switch to whatever implicit per-buffer
   synchronisation mechanism gets merged, once something is merged.
 * It abuses flags parameter of DRM_IOCTL_MODE_CREATE_DUMB to also
   allocate buffers for the GPU. Still not sure how to resolve this
   as we don't use DRM for our GPU driver.

any thoughts/plans about a DRM GPU driver?  Ideally long term (esp.
once the dma-fence stuff is in place), we'd have gpu-specific drm
(gpu-only, no kms) driver, and SoC/display specific drm/kms driver,
using prime/dmabuf to share between the two.

The PL111 primecell is just a scanout device.  It has no GPU embedded
in it.  It's just like the Armada/Dove DRM stuff - if a GPU is provided
it's an entirely separate piece of IP, and will likely remain a separate
non-DRM driver.

In the case of PL111, PL111 is not manufacturer specific so the GPU can
be any standalone GPU.

Oh, yeah, I know PL111 is different block independent from GPU.  I
wasn't advocating adding mali support in this driver.  But instead
creating a mali DRM driver which had GEM and gpu bits, but not KMS.
Then buffer sharing w/ prime/dmabuf just like you would, for example
on a laptop w/ both integrated graphics and discrete GPU.

BR,
-R