On Sun, 24 Oct 2021, Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
> In intel_dsi_get_config() double the pclk returned by foo_dsi_get_pclk()
> for dual-link panels. This fixes the following WARN triggering:
>
> i915 0000:00:02.0: [drm] *ERROR* [CRTC:51:pipe A] mismatch in pixel_rate (expected 235710, found 118056)
> i915 0000:00:02.0: [drm] *ERROR* [CRTC:51:pipe A] mismatch in hw.pipe_mode.crtc_clock (expected 235710, found 118056)
> i915 0000:00:02.0: [drm] *ERROR* [CRTC:51:pipe A] mismatch in hw.adjusted_mode.crtc_clock (expected 235710, found 118056)
> i915 0000:00:02.0: [drm] *ERROR* [CRTC:51:pipe A] mismatch in port_clock (expected 235710, found 118056)
> ------------[ cut here ]------------
> pipe state doesn't match!
> WARNING: CPU: 3 PID: 136 at drivers/gpu/drm/i915/display/intel_display.c:9125 intel_display_finish_reset+0x1bd3/0x2050 [i915]
> ...
>
> This has been tested on a Xiaomi Mi Pad 2 (with CHT x5-Z8500 SoC) tablet,
> with a 1536x2048 dual-link DSI panel.
>
> Note this fix was taken from icl_dsi.c which does the same in
> its get_config().
>
> Cc: Tsuchiya Yuto <kitakar@xxxxxxxxx>
> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Acked-by: Jani Nikula <jani.nikula@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/display/vlv_dsi.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/display/vlv_dsi.c b/drivers/gpu/drm/i915/display/vlv_dsi.c
> index 3e646a58b38a..2b7909bc52ff 100644
> --- a/drivers/gpu/drm/i915/display/vlv_dsi.c
> +++ b/drivers/gpu/drm/i915/display/vlv_dsi.c
> @@ -1265,7 +1265,9 @@ static void intel_dsi_get_config(struct intel_encoder *encoder,
> struct intel_crtc_state *pipe_config)
> {
> struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
> + struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
> u32 pclk;
> +
> drm_dbg_kms(&dev_priv->drm, "\n");
>
> pipe_config->output_types |= BIT(INTEL_OUTPUT_DSI);
> @@ -1277,6 +1279,9 @@ static void intel_dsi_get_config(struct intel_encoder *encoder,
> pclk = vlv_dsi_get_pclk(encoder, pipe_config);
> }
>
> + if (intel_dsi->dual_link)
> + pclk *= 2;
> +
> if (pclk) {
> pipe_config->hw.adjusted_mode.crtc_clock = pclk;
> pipe_config->port_clock = pclk;
--
Jani Nikula, Intel Open Source Graphics Center
