On Mon, Nov 11, 2019 at 03:47:22AM -0800, Devarsh Thakkar wrote: > For the scenario where user may require to modeset with a mode > supporting a fractional value for vertical refresh-rate, > appropriate mode can be selected by searching for mode > having matching fractional vertical refresh rate using > below equation. > > vrefresh = (1000 * pixel clock) / (htotal * vtotal) Hz. > > We do this way since driver doesn't return float value of vrefresh > as it use int for vrefresh in struct drm_mode_info, but we can derive > the actual value using pixel clock, horizontal total size and > vertical total size values. > > So for e.g. if user want to select mode having 59.94 Hz as refresh rate > then with this patch it be can done as shown in below command, > given there is an appropriate mode is available : > > modetest -M xlnx -s 39:1920x1080-59.94@BG24 -v > > NOTE: Above command was tested on xilinx DRM driver with DP > monitor which was supporting mode having 59.94 Hz refresh rate. > > Signed-off-by: Devarsh Thakkar <devarsh.thakkar@xxxxxxxxxx> > --- > V2: Update commit message > V3: Update with below changes as per review comments : > 1) Use epsilon for vrefresh comparison > 2) Use implicit type-casting wherever possible Please keep these in the commit msg proper. We prefer these things to hang around even when the patch gets pushed. Patch lgtm. Reviewed-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > This email and any attachments are intended for the sole use of the named recipient(s) and contain(s) confidential information that may be proprietary, privileged or copyrighted under applicable law. If you are not the intended recipient, do not read, copy, or forward this email message or any attachments. Delete this email message and any attachments immediately. You should do something to eliminate this. Doesn't make sense for open source stuff. -- Ville Syrjälä Intel _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
