drm/i915: remove check for aux irq

This became dead code with commit 309bd8ed464f ("drm/i915: Reinstate
GMBUS and AUX interrupts on gen4/g4x").

v2: Move comment about HW behavior to where decision is made to enable
MSI (Ville).

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180523180435.18042-1-lucas.demarchi@intel.com

drivers/gpu/drm/i915/i915_drv.c

@@ -1165,6 +1165,12 @@ static int i915_driver_init_hw(struct drm_i915_private *dev_priv)
 	 * get lost on g4x as well, and interrupt delivery seems to stay
 	 * properly dead afterwards. So we'll just disable them for all
 	 * pre-gen5 chipsets.
+	 *
+	 * dp aux and gmbus irq on gen4 seems to be able to generate legacy
+	 * interrupts even when in MSI mode. This results in spurious
+	 * interrupt warnings if the legacy irq no. is shared with another
+	 * device. The kernel then disables that interrupt source and so
+	 * prevents the other device from working properly.
 	 */
 	if (INTEL_GEN(dev_priv) >= 5) {
 		if (pci_enable_msi(pdev) < 0)

drivers/gpu/drm/i915/i915_drv.h

@@ -2581,16 +2581,6 @@ intel_info(const struct drm_i915_private *dev_priv)
 	(IS_CANNONLAKE(dev_priv) || \
 	 IS_SKL_GT3(dev_priv) || IS_SKL_GT4(dev_priv))
 
-/*
- * dp aux and gmbus irq on gen4 seems to be able to generate legacy interrupts
- * even when in MSI mode. This results in spurious interrupt warnings if the
- * legacy irq no. is shared with another device. The kernel then disables that
- * interrupt source and so prevents the other device from working properly.
- *
- * Since we don't enable MSI anymore on gen4, we can always use GMBUS/AUX
- * interrupts.
- */
-#define HAS_AUX_IRQ(dev_priv)   true
 #define HAS_GMBUS_IRQ(dev_priv) (INTEL_GEN(dev_priv) >= 4)
 
 /* With the 945 and later, Y tiling got adjusted so that it was 32 128-byte

drivers/gpu/drm/i915/intel_dp.c

@@ -953,7 +953,7 @@ intel_dp_check_edp(struct intel_dp *intel_dp)
 }
 
 static uint32_t
-intel_dp_aux_wait_done(struct intel_dp *intel_dp, bool has_aux_irq)
+intel_dp_aux_wait_done(struct intel_dp *intel_dp)
 {
 	struct drm_i915_private *dev_priv = to_i915(intel_dp_to_dev(intel_dp));
 	i915_reg_t ch_ctl = intel_dp->aux_ch_ctl_reg(intel_dp);
@@ -961,14 +961,10 @@ intel_dp_aux_wait_done(struct intel_dp *intel_dp, bool has_aux_irq)
 	bool done;
 
 #define C (((status = I915_READ_NOTRACE(ch_ctl)) & DP_AUX_CH_CTL_SEND_BUSY) == 0)
-	if (has_aux_irq)
-		done = wait_event_timeout(dev_priv->gmbus_wait_queue, C,
-					  msecs_to_jiffies_timeout(10));
-	else
-		done = wait_for(C, 10) == 0;
+	done = wait_event_timeout(dev_priv->gmbus_wait_queue, C,
+				  msecs_to_jiffies_timeout(10));
 	if (!done)
-		DRM_ERROR("dp aux hw did not signal timeout (has irq: %i)!\n",
-			  has_aux_irq);
+		DRM_ERROR("dp aux hw did not signal timeout!\n");
 #undef C
 
 	return status;
@@ -1033,7 +1029,6 @@ static uint32_t skl_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
 }
 
 static uint32_t g4x_get_aux_send_ctl(struct intel_dp *intel_dp,
-				     bool has_aux_irq,
 				     int send_bytes,
 				     uint32_t aux_clock_divider)
 {
@@ -1054,7 +1049,7 @@ static uint32_t g4x_get_aux_send_ctl(struct intel_dp *intel_dp,
 
 	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_INTERRUPT |
 	       DP_AUX_CH_CTL_TIME_OUT_ERROR |
 	       timeout |
 	       DP_AUX_CH_CTL_RECEIVE_ERROR |
@@ -1064,13 +1059,12 @@ static uint32_t g4x_get_aux_send_ctl(struct intel_dp *intel_dp,
 }
 
 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_INTERRUPT |
 	       DP_AUX_CH_CTL_TIME_OUT_ERROR |
 	       DP_AUX_CH_CTL_TIME_OUT_MAX |
 	       DP_AUX_CH_CTL_RECEIVE_ERROR |
@@ -1093,7 +1087,6 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp,
 	int i, ret, recv_bytes;
 	uint32_t status;
 	int try, clock = 0;
-	bool has_aux_irq = HAS_AUX_IRQ(dev_priv);
 	bool vdd;
 
 	ch_ctl = intel_dp->aux_ch_ctl_reg(intel_dp);
@@ -1148,7 +1141,6 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp,
 
 	while ((aux_clock_divider = intel_dp->get_aux_clock_divider(intel_dp, clock++))) {
 		u32 send_ctl = intel_dp->get_aux_send_ctl(intel_dp,
-							  has_aux_irq,
 							  send_bytes,
 							  aux_clock_divider);
 
@@ -1165,7 +1157,7 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp,
 			/* Send the command and wait for it to complete */
 			I915_WRITE(ch_ctl, send_ctl);
 
-			status = intel_dp_aux_wait_done(intel_dp, has_aux_irq);
+			status = intel_dp_aux_wait_done(intel_dp);
 
 			/* Clear done status and any errors */
 			I915_WRITE(ch_ctl,

drivers/gpu/drm/i915/intel_drv.h

@@ -1132,7 +1132,6 @@ struct intel_dp {
 	 * register with to kick off an AUX transaction.
 	 */
 	uint32_t (*get_aux_send_ctl)(struct intel_dp *dp,
-				     bool has_aux_irq,
 				     int send_bytes,
 				     uint32_t aux_clock_divider);
 

drivers/gpu/drm/i915/intel_psr.c

@@ -336,7 +336,7 @@ static void hsw_psr_setup_aux(struct intel_dp *intel_dp)
 	aux_clock_divider = intel_dp->get_aux_clock_divider(intel_dp, 0);
 
 	/* Start with bits set for DDI_AUX_CTL register */
-	aux_ctl = intel_dp->get_aux_send_ctl(intel_dp, 0, sizeof(aux_msg),
+	aux_ctl = intel_dp->get_aux_send_ctl(intel_dp, sizeof(aux_msg),
 					     aux_clock_divider);
 
 	/* Select only valid bits for SRD_AUX_CTL */