Re: [PATCH 7/6] drm/i915/skl: DDI-E and DDI-A shares 4 lanes.

Timo Aaltonen
2015-08-12T21:29:18Z

On 11.08.2015 10:05, Zhang, Xiong Y wrote:
>> -----Original Message-----
>> From: Vivi, Rodrigo
>> Sent: Saturday, August 8, 2015 8:34 AM
>> To: intel-gfx@lists.freedesktop.org
>> Cc: Vivi, Rodrigo; Zhang, Xiong Y
>> Subject: [PATCH 7/6] drm/i915/skl: DDI-E and DDI-A shares 4 lanes.
>>
>> DDI-A and DDI-E shares the 4 lanes. So when DDI-E is present we need to
>> configure lane count propperly for both.
>>
>> This was based on Sonika's
>> [PATCH] drm/i915/skl: Select DDIA lane capability based upon vbt
>>
>> Credits-to: Sonika Jindal <sonika.jindal@intel.com>
>> Cc: Xiong Zhang <xiong.y.zhang@intel.com>
>> Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
>> ---
>> drivers/gpu/drm/i915/intel_ddi.c | 12 ++++++++++--
>> drivers/gpu/drm/i915/intel_dp.c | 8 +++++---
>> 2 files changed, 15 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_ddi.c
>> b/drivers/gpu/drm/i915/intel_ddi.c
>> index 110d546..557cecf 100644
>> --- a/drivers/gpu/drm/i915/intel_ddi.c
>> +++ b/drivers/gpu/drm/i915/intel_ddi.c
>> @@ -3178,7 +3178,15 @@ void intel_ddi_init(struct drm_device *dev, enum
>> port port)
>> struct intel_digital_port *intel_dig_port;
>> struct intel_encoder *intel_encoder;
>> struct drm_encoder *encoder;
>> - bool init_hdmi, init_dp;
>> + bool init_hdmi, init_dp, ddi_e_present;
>> +
>> + /*
>> + * On SKL we don't have a way to detect DDI-E so we rely on VBT.
>> + */
>> + ddie_present = IS_SKYLAKE(dev) &&
>> + (dev_priv->vbt.ddi_port_info[PORT_E].supports_dp ||
>> + dev_priv->vbt.ddi_port_info[PORT_E].supports_dvi ||
>> + dev_priv->vbt.ddi_port_info[PORT_E].supports_hdmi);
> [Zhang, Xiong Y] ddie_present should be ddi_e_present
>>
>> init_hdmi = (dev_priv->vbt.ddi_port_info[port].supports_dvi ||
>> dev_priv->vbt.ddi_port_info[port].supports_hdmi);
>> @@ -3210,7 +3218,7 @@ void intel_ddi_init(struct drm_device *dev, enum
>> port port)
>> intel_dig_port->port = port;
>> intel_dig_port->saved_port_bits = I915_READ(DDI_BUF_CTL(port)) &
>> (DDI_BUF_PORT_REVERSAL |
>> - DDI_A_4_LANES);
>> + ddi_e_present ? 0 : DDI_A_4_LANES);
> [Zhang, Xiong Y] Sonika's patch will set DDI-A to 4 lanes when DDI-E doesn't exist,
> I think your patch will do nothing.
>>
>> intel_encoder->type = INTEL_OUTPUT_UNKNOWN;
>> intel_encoder->crtc_mask = (1 << 0) | (1 << 1) | (1 << 2); diff --git
>> a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index
>> 3ff2080..7ada79e 100644
>> --- a/drivers/gpu/drm/i915/intel_dp.c
>> +++ b/drivers/gpu/drm/i915/intel_dp.c
>> @@ -159,9 +159,11 @@ static u8 intel_dp_max_lane_count(struct intel_dp
>> *intel_dp)
>> u8 source_max, sink_max;
>>
>> source_max = 4;
>> - if (HAS_DDI(dev) && intel_dig_port->port == PORT_A &&
>> - (intel_dig_port->saved_port_bits & DDI_A_4_LANES) == 0)
>> - source_max = 2;
>> + if (HAS_DDI(dev) && (intel_dig_port->port == PORT_E ||
>> + (intel_dig_port->port == PORT_A &&
>> + (intel_dig_port->saved_port_bits &
>> + DDI_A_4_LANES) == 0))
>> + source_max = 2;
> [Zhang, Xiong Y] it miss ')' at the end line.
>>
>> sink_max = drm_dp_max_lane_count(intel_dp->dpcd);

with these build fixes the series is

Tested-by: Timo Aaltonen <timo.aaltonen@canonical.com>

the VGA port on SKL-H SDP was functional after all.. (DP-to-VGA)

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