diff mbox

[v4,10/11] drm/i915: DVO pixel clock check

Message ID 1439546611-3191-11-git-send-email-mika.kahola@intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Mika Kahola Aug. 14, 2015, 10:03 a.m. UTC
It is possible the we request to have a mode that has
higher pixel clock than our HW can support. This patch
checks if requested pixel clock is lower than the one
supported by the HW. The requested mode is discarded
if we cannot support the requested pixel clock.

This patch applies to DVO.

V2:
- removed computation for max pixel clock

V3:
- cleanup by removing unnecessary lines

V4:
- clock check against max dotclock moved inside 'if (fixed_mode)'

Signed-off-by: Mika Kahola <mika.kahola@intel.com>
---
 drivers/gpu/drm/i915/intel_dvo.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Ville Syrjälä Aug. 14, 2015, 1:10 p.m. UTC | #1
On Fri, Aug 14, 2015 at 01:03:30PM +0300, Mika Kahola wrote:
> It is possible the we request to have a mode that has
> higher pixel clock than our HW can support. This patch
> checks if requested pixel clock is lower than the one
> supported by the HW. The requested mode is discarded
> if we cannot support the requested pixel clock.
> 
> This patch applies to DVO.
> 
> V2:
> - removed computation for max pixel clock
> 
> V3:
> - cleanup by removing unnecessary lines
> 
> V4:
> - clock check against max dotclock moved inside 'if (fixed_mode)'
> 
> Signed-off-by: Mika Kahola <mika.kahola@intel.com>
> ---
>  drivers/gpu/drm/i915/intel_dvo.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/intel_dvo.c b/drivers/gpu/drm/i915/intel_dvo.c
> index dc532bb..924b724 100644
> --- a/drivers/gpu/drm/i915/intel_dvo.c
> +++ b/drivers/gpu/drm/i915/intel_dvo.c
> @@ -201,6 +201,7 @@ intel_dvo_mode_valid(struct drm_connector *connector,
>  		     struct drm_display_mode *mode)
>  {
>  	struct intel_dvo *intel_dvo = intel_attached_dvo(connector);
> +	int max_dotclk = to_i915(connector->dev)->max_dotclk_freq;
>  
>  	if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
>  		return MODE_NO_DBLESCAN;
> @@ -212,6 +213,8 @@ intel_dvo_mode_valid(struct drm_connector *connector,
>  			return MODE_PANEL;
>  		if (mode->vdisplay > intel_dvo->panel_fixed_mode->vdisplay)
>  			return MODE_PANEL;
> +		if (mode->clock > max_dotclk)
> +			return MODE_CLOCK_HIGH;
>  	}

What we want here is duplicate the intel_dp.c logic exactly, ie. check
against fixed_mode->clock when it's around, otherwise check against
mode->clock.

>  
>  	return intel_dvo->dev.dev_ops->mode_valid(&intel_dvo->dev, mode);
> -- 
> 1.9.1
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/intel_dvo.c b/drivers/gpu/drm/i915/intel_dvo.c
index dc532bb..924b724 100644
--- a/drivers/gpu/drm/i915/intel_dvo.c
+++ b/drivers/gpu/drm/i915/intel_dvo.c
@@ -201,6 +201,7 @@  intel_dvo_mode_valid(struct drm_connector *connector,
 		     struct drm_display_mode *mode)
 {
 	struct intel_dvo *intel_dvo = intel_attached_dvo(connector);
+	int max_dotclk = to_i915(connector->dev)->max_dotclk_freq;
 
 	if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
 		return MODE_NO_DBLESCAN;
@@ -212,6 +213,8 @@  intel_dvo_mode_valid(struct drm_connector *connector,
 			return MODE_PANEL;
 		if (mode->vdisplay > intel_dvo->panel_fixed_mode->vdisplay)
 			return MODE_PANEL;
+		if (mode->clock > max_dotclk)
+			return MODE_CLOCK_HIGH;
 	}
 
 	return intel_dvo->dev.dev_ops->mode_valid(&intel_dvo->dev, mode);