On 08.04.21 15:19, Arnd Bergmann wrote:
On Thu, Apr 8, 2021 at 2:50 PM Linus Walleij linus.walleij@linaro.org wrote:
On Thu, Apr 8, 2021 at 2:01 PM David Hildenbrand david@redhat.com wrote:
This is something you could do using a hidden helper symbol like
config DRMA_ASPEED_GFX bool "Aspeed display driver" select DRM_WANT_CMA
config DRM_WANT_CMA bool help Select this from any driver that benefits from CMA being enabled
config DMA_CMA bool "Use CMA helpers for DRM" default DRM_WANT_CMA
ArndThat's precisely what I had first, with an additional "WANT_CMA" -- but looking at the number of such existing options (I was able to spot 1 !)
If you do this it probably makes sense to fix a few other drivers Kconfig in the process. It's not just a problem with your driver. "my" drivers:
drivers/gpu/drm/mcde/Kconfig drivers/gpu/drm/pl111/Kconfig drivers/gpu/drm/tve200/Kconfig
certainly needs this as well, and pretty much anything that is selecting DRM_KMS_CMA_HELPER or DRM_GEM_CMA_HELPER "wants" DMA_CMA.
Are there any that don't select either of the helpers and still want CMA? If not, it would be easy to just add
default DRM_KMS_CMA_HELPER || DRM_GEM_CMA_HELPERand skipt the extra symbol.
That sounds like a reasonable thing to do. I'll look into that.