[Intel-gfx] [PATCH 22/89] drm/i915/skl: Provide a get_aux_send_ctl() vfunc for skylake

[Damien Lespiau]

Skylake doesn't use the pre-charge field now, but, instead, we need to
specify the total number of SYNC pulses for the SYNC phase (pre-charge +
SYNC pattern pules). Let's use the default value (32) for that.

v3: increase DP AUX TX timeout as 400us is not to be used on SKL
    apparently (Jesse).

Signed-off-by: Damien Lespiau <damien.lespiau at intel.com>
---
 drivers/gpu/drm/i915/i915_reg.h |  1 +
 drivers/gpu/drm/i915/intel_dp.c | 20 +++++++++++++++++++-
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 087085c..acd0a7b 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -3630,6 +3630,7 @@ enum punit_power_well {
 #define   DP_AUX_CH_CTL_PRECHARGE_TEST	    (1 << 11)
 #define   DP_AUX_CH_CTL_BIT_CLOCK_2X_MASK    (0x7ff)
 #define   DP_AUX_CH_CTL_BIT_CLOCK_2X_SHIFT   0
+#define   DP_AUX_CH_CTL_SYNC_PULSE_SKL(c)   ((c) - 1)
 
 /*
  * Computing GMCH M and N values for the Display Port link
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 4560ced..5755f59 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -529,6 +529,21 @@ static uint32_t i9xx_get_aux_send_ctl(struct intel_dp *intel_dp,
 	       (aux_clock_divider << DP_AUX_CH_CTL_BIT_CLOCK_2X_SHIFT);
 }
 
+static uint32_t skl_get_aux_send_ctl(struct intel_dp *intel_dp,
+				      bool has_aux_irq,
+				      int send_bytes,
+				      uint32_t unused)
+{
+	return DP_AUX_CH_CTL_SEND_BUSY |
+	       DP_AUX_CH_CTL_DONE |
+	       (has_aux_irq ? DP_AUX_CH_CTL_INTERRUPT : 0) |
+	       DP_AUX_CH_CTL_TIME_OUT_ERROR |
+	       DP_AUX_CH_CTL_TIME_OUT_1600us |
+	       DP_AUX_CH_CTL_RECEIVE_ERROR |
+	       (send_bytes << DP_AUX_CH_CTL_MESSAGE_SIZE_SHIFT) |
+	       DP_AUX_CH_CTL_SYNC_PULSE_SKL(32);
+}
+
 static int
 intel_dp_aux_ch(struct intel_dp *intel_dp,
 		uint8_t *send, int send_bytes,
@@ -4747,7 +4762,10 @@ intel_dp_init_connector(struct intel_digital_port *intel_dig_port,
 	else
 		intel_dp->get_aux_clock_divider = i9xx_get_aux_clock_divider;
 
-	intel_dp->get_aux_send_ctl = i9xx_get_aux_send_ctl;
+	if (INTEL_INFO(dev)->gen >= 9)
+		intel_dp->get_aux_send_ctl = skl_get_aux_send_ctl;
+	else
+		intel_dp->get_aux_send_ctl = i9xx_get_aux_send_ctl;
 
 	/* Preserve the current hw state. */
 	intel_dp->DP = I915_READ(intel_dp->output_reg);
-- 
1.8.3.1