Hello Giulio, this patch breaks LVDS output on A83T. Without it, modesetting works, with it there's no output.
Some more info below... On Tue, Mar 13, 2018 at 12:20:19PM +0100, Giulio Benetti wrote: > mode_valid function is missing for lvds. > > Add it making it pointed by encoder helper functions. > > Signed-off-by: Giulio Benetti <giulio.bene...@micronovasrl.com> > --- > drivers/gpu/drm/sun4i/sun4i_lvds.c | 55 > ++++++++++++++++++++++++++++++++++++++ > 1 file changed, 55 insertions(+) > > diff --git a/drivers/gpu/drm/sun4i/sun4i_lvds.c > b/drivers/gpu/drm/sun4i/sun4i_lvds.c > index be3f14d..bffff4c 100644 > --- a/drivers/gpu/drm/sun4i/sun4i_lvds.c > +++ b/drivers/gpu/drm/sun4i/sun4i_lvds.c > @@ -94,9 +94,64 @@ static void sun4i_lvds_encoder_disable(struct drm_encoder > *encoder) > } > } > > +static enum drm_mode_status sun4i_lvds_encoder_mode_valid(struct drm_encoder > *crtc, > + const struct > drm_display_mode *mode) > +{ > + struct sun4i_lvds *lvds = drm_encoder_to_sun4i_lvds(crtc); > + struct sun4i_tcon *tcon = lvds->tcon; > + u32 hsync = mode->hsync_end - mode->hsync_start; > + u32 vsync = mode->vsync_end - mode->vsync_start; > + unsigned long rate = mode->clock * 1000; > + long rounded_rate; > + > + DRM_DEBUG_DRIVER("Validating modes...\n"); > + > + if (hsync < 1) > + return MODE_HSYNC_NARROW; > + > + if (hsync > 0x3ff) > + return MODE_HSYNC_WIDE; > + > + if ((mode->hdisplay < 1) || (mode->htotal < 1)) > + return MODE_H_ILLEGAL; > + > + if ((mode->hdisplay > 0x7ff) || (mode->htotal > 0xfff)) > + return MODE_BAD_HVALUE; > + > + DRM_DEBUG_DRIVER("Horizontal parameters OK\n"); > + > + if (vsync < 1) > + return MODE_VSYNC_NARROW; > + > + if (vsync > 0x3ff) > + return MODE_VSYNC_WIDE; > + > + if ((mode->vdisplay < 1) || (mode->vtotal < 1)) > + return MODE_V_ILLEGAL; > + > + if ((mode->vdisplay > 0x7ff) || (mode->vtotal > 0xfff)) > + return MODE_BAD_VVALUE; > + > + DRM_DEBUG_DRIVER("Vertical parameters OK\n"); > + > + tcon->dclk_min_div = 7; > + tcon->dclk_max_div = 7; Why would validation function change any state anywhere? > + rounded_rate = clk_round_rate(tcon->dclk, rate); The issue is here, on A83T TBS A711 tablet, I get... sun4i-tcon 1c0c000.lcd-controller: XXX: hsync=20 hdisplay=1024 htotal=1384 vsync=5 vdisplay=600 vtotal=640 rate=52000000 rounded_rate=51857142 > + if (rounded_rate < rate) > + return MODE_CLOCK_LOW; > + > + if (rounded_rate > rate) > + return MODE_CLOCK_HIGH; ... while the previous conditions require an exact match for some reason. But HW works fine without an exact rate match. Why is exact match required here? thank you, Ondrej > + DRM_DEBUG_DRIVER("Clock rate OK\n"); > + > + return MODE_OK; > +} > + > static const struct drm_encoder_helper_funcs sun4i_lvds_enc_helper_funcs = { > .disable = sun4i_lvds_encoder_disable, > .enable = sun4i_lvds_encoder_enable, > + .mode_valid = sun4i_lvds_encoder_mode_valid, > }; > > static const struct drm_encoder_funcs sun4i_lvds_enc_funcs = { _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel