drm/i915/dp: Track pm_qos per connector

Since multiple connectors may run intel_dp_aux_xfer conncurrently, a
single global pm_qos does not suffice. (One connector may disable the
dma-latency boost prematurely while the second is still depending on
it.) Instead of a single global pm_qos, track the pm_qos request for
each intel_dp.

v2: Move the pm_qos setup/teardown to intel_dp_aux_init/fini

Fixes: 9ee32fea ("drm/i915: irq-drive the dp aux communication")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201230202309.23982-1-chris@chris-wilson.co.uk
(cherry picked from commit b3304591)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

drivers/gpu/drm/i915/display/intel_display_types.h

@@ -1436,6 +1436,9 @@ struct intel_dp {
 		bool ycbcr_444_to_420;
 	} dfp;
 
+	/* To control wakeup latency, e.g. for irq-driven dp aux transfers. */
+	struct pm_qos_request pm_qos;
+
 	/* Display stream compression testing */
 	bool force_dsc_en;
 

drivers/gpu/drm/i915/display/intel_dp.c

@@ -1489,7 +1489,7 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp,
 	 * lowest possible wakeup latency and so prevent the cpu from going into
 	 * deep sleep states.
 	 */
-	cpu_latency_qos_update_request(&i915->pm_qos, 0);
+	cpu_latency_qos_update_request(&intel_dp->pm_qos, 0);
 
 	intel_dp_check_edp(intel_dp);
 
@@ -1622,7 +1622,7 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp,
 
 	ret = recv_bytes;
 out:
-	cpu_latency_qos_update_request(&i915->pm_qos, PM_QOS_DEFAULT_VALUE);
+	cpu_latency_qos_update_request(&intel_dp->pm_qos, PM_QOS_DEFAULT_VALUE);
 
 	if (vdd)
 		edp_panel_vdd_off(intel_dp, false);
@@ -1898,6 +1898,9 @@ static i915_reg_t tgl_aux_data_reg(struct intel_dp *intel_dp, int index)
 static void
 intel_dp_aux_fini(struct intel_dp *intel_dp)
 {
+	if (cpu_latency_qos_request_active(&intel_dp->pm_qos))
+		cpu_latency_qos_remove_request(&intel_dp->pm_qos);
+
 	kfree(intel_dp->aux.name);
 }
 
@@ -1950,6 +1953,7 @@ intel_dp_aux_init(struct intel_dp *intel_dp)
 					       encoder->base.name);
 
 	intel_dp->aux.transfer = intel_dp_aux_transfer;
+	cpu_latency_qos_add_request(&intel_dp->pm_qos, PM_QOS_DEFAULT_VALUE);
 }
 
 bool intel_dp_source_supports_hbr2(struct intel_dp *intel_dp)

drivers/gpu/drm/i915/i915_drv.c

@@ -578,8 +578,6 @@ static int i915_driver_hw_probe(struct drm_i915_private *dev_priv)
 
 	pci_set_master(pdev);
 
-	cpu_latency_qos_add_request(&dev_priv->pm_qos, PM_QOS_DEFAULT_VALUE);
-
 	intel_gt_init_workarounds(dev_priv);
 
 	/* On the 945G/GM, the chipset reports the MSI capability on the
@@ -626,7 +624,6 @@ static int i915_driver_hw_probe(struct drm_i915_private *dev_priv)
 err_msi:
 	if (pdev->msi_enabled)
 		pci_disable_msi(pdev);
-	cpu_latency_qos_remove_request(&dev_priv->pm_qos);
 err_mem_regions:
 	intel_memory_regions_driver_release(dev_priv);
 err_ggtt:
@@ -648,8 +645,6 @@ static void i915_driver_hw_remove(struct drm_i915_private *dev_priv)
 
 	if (pdev->msi_enabled)
 		pci_disable_msi(pdev);
-
-	cpu_latency_qos_remove_request(&dev_priv->pm_qos);
 }
 
 /**

drivers/gpu/drm/i915/i915_drv.h

@@ -891,9 +891,6 @@ struct drm_i915_private {
 
 	bool display_irqs_enabled;
 
-	/* To control wakeup latency, e.g. for irq-driven dp aux transfers. */
-	struct pm_qos_request pm_qos;
-
 	/* Sideband mailbox protection */
 	struct mutex sb_lock;
 	struct pm_qos_request sb_qos;