For ATI GPU the crtc_base could be the base pointer to the memory buffer: ./drivers/gpu/drm/radeon/rv770.c: u32 rv770_page_flip(struct radeon_device *rdev, int crtc_id, u64 crtc_base)
./drivers/gpu/drm/radeon/rs600.c: void rs600_pre_page_flip(struct radeon_device *rdev, int crtc) void rs600_post_page_flip(struct radeon_device *rdev, int crtc) u32 rs600_page_flip(struct radeon_device *rdev, int crtc_id, u64 crtc_base) As to the internals of these buffer area, well, u may need the datasheet from the vendor. Just grep for "CRTC" inside the gpu/drm/radeon directory and you can understand why. On Thu, Jan 16, 2014 at 3:44 PM, Peter Teoh <[email protected]> wrote: > In general how it worked is explained here: > > https://www.kernel.org/doc/htmldocs/drm/drm-kms-init.html > > Not sure which is the name of your video card, but I think in general all > the page flip API should have access to the scan buffer (see link above). > For Intel these are possible APIs > : > > > static void do_intel_finish_page_flip(struct drm_device *dev, > void intel_finish_page_flip(struct drm_device *dev, int pipe) > do_intel_finish_page_flip(dev, crtc); > void intel_finish_page_flip_plane(struct drm_device *dev, int plane) > do_intel_finish_page_flip(dev, crtc); > void intel_prepare_page_flip(struct drm_device *dev, int plane) > * is also accompanied by a spurious intel_prepare_page_flip(). > inline static void intel_mark_page_flip_active(struct intel_crtc > *intel_crtc) > > > On Sat, Jan 11, 2014 at 9:27 PM, Sannu K <[email protected]> wrote: > >> Hi, >> >> I would like to access a monitor's content in kernel mode. I tried but >> could not find a generic way to access CRTC's scan out buffer in kernel >> mode. I prefer to do it in kernel mode as an experiment. Any pointers will >> greatly help. >> >> Thanks and Regards, >> Sannu K >> >> _______________________________________________ >> Kernelnewbies mailing list >> [email protected] >> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies >> >> > > > -- > Regards, > Peter Teoh > -- Regards, Peter Teoh
_______________________________________________ Kernelnewbies mailing list [email protected] http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
