On 10/31/2024, Liu Ying wrote: > Hi Maxime, > > On 10/30/2024, Maxime Ripard wrote: >> On Mon, Oct 28, 2024 at 10:37:30AM +0800, Liu Ying wrote: >>> Multiple display modes could be read from a display device's EDID. >>> Use clk_round_rate() to validate the "ldb" clock rate for each mode >>> in drm_bridge_funcs::mode_valid() to filter unsupported modes out. >>> >>> Also, since this driver doesn't directly reference pixel clock, use >>> clk_round_rate() to validate the pixel clock rate against the "ldb" >>> clock if the "ldb" clock and the pixel clock are sibling in clock >>> tree. This is not done in display controller driver because >>> drm_crtc_helper_funcs::mode_valid() may not decide to do the >>> validation or not if multiple encoders are connected to the CRTC, >>> e.g., i.MX93 LCDIF may connect with MIPI DSI controller, LDB and >>> parallel display output simultaneously. >>> >>> Signed-off-by: Liu Ying <[email protected]> >>> --- >>> Note that this patch depends on a patch in shawnguo/imx/fixes: >>> https://patchwork.kernel.org/project/linux-arm-kernel/patch/[email protected]/ >> >> I still believe that the root cause of this issue is your clock tree and >> driver setup, and since I've asked for explanations and didn't get any, >> I don't really see how we can move forward here. > > Since you asked for a description at *somewhere* in another thread[1], > can you please suggest a place where this could happen?
I have written a description in the cover letter of this patch series(v7): https://patchwork.freedesktop.org/series/139266/#rev7 If you don't mind, please provide review comments there, thanks. > > [1] > https://lore.kernel.org/imx/[email protected]/T/#m587e6a25bdab542d5d99abbf01caaca89495b1d5 > >> >> Maxime > -- Regards, Liu Ying
