[Intel-gfx] [PATCH] drm/i915: Allow LVDS on pipe A on gen4+

[ykzhao]

On Sun, 2010-04-04 at 03:46 +0800, Pierre Willenbrock wrote:
> Adam Jackson schrieb:
> > The gen4 docs say it works, so why not.  Tested on Ironlake.
> > 
> 
> Looks like my i965 based laptop is not happy with this patch(well, the
> version in erics repository). I get a black screen on LVDS(although
> backlight works as always).
> 
> The problem is not necessarily the inability of that chip to handle LVDS
> on pipe A: The dot clock differs according to intel_reg_dumper, and i
> get a new warning.
> 
> Output of intel_reg_dumper with and without this patch is attached.

Hi, Pierre
    Will you please try the following patch and see whether it can work for you?
       
Thanks.


The gen4 docs say it works, so why not.  Tested on Ironlake.

Signed-off-by: Adam Jackson <ajax at redhat.com>
---
 drivers/gpu/drm/i915/intel_display.c |    5 ++++-
 drivers/gpu/drm/i915/intel_lvds.c    |    2 ++
 2 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index b27202d..05e2201 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3286,7 +3286,10 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
 			lvds_reg = PCH_LVDS;
 
 		lvds = I915_READ(lvds_reg);
-		lvds |= LVDS_PORT_EN | LVDS_A0A2_CLKA_POWER_UP | LVDS_PIPEB_SELECT;
+		lvds |= LVDS_PORT_EN | LVDS_A0A2_CLKA_POWER_UP;
+		lvds &= ~LVDS_PIPEB_SELECT;
+		if (pipe == 1)
+			lvds |= LVDS_PIPEB_SELECT;
 		/* set the corresponsding LVDS_BORDER bit */
 		lvds |= dev_priv->lvds_border_bits;
 		/* Set the B0-B3 data pairs corresponding to whether we're going to
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index 93031a7..c810ad6 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -1056,6 +1056,8 @@ void intel_lvds_init(struct drm_device *dev)
 
 	intel_output->clone_mask = (1 << INTEL_LVDS_CLONE_BIT);
 	intel_output->crtc_mask = (1 << 1);
+	if (IS_I965G(dev))
+		intel_output->crtc_mask |= (1 << 0);
 	drm_encoder_helper_add(encoder, &intel_lvds_helper_funcs);
 	drm_connector_helper_add(connector, &intel_lvds_connector_helper_funcs);
 	connector->display_info.subpixel_order = SubPixelHorizontalRGB;
-- 
1.5.4.5


> 
> Regards,
>   Pierre
>