drm/i915: Get power refs in encoder->get_power_domains()

Push getting the reference for the encoders' power domains into the
encoder get_power_domains() hook instead of doing this from the caller.
This way the encoder can store away the corresponding wakerefs.

This fixes the DSI encoder disabling, which didn't release these
power references it acquired during HW state readout.

Note that longtime ownership for the corresponding wakerefs can be thus
acquired / released in two ways. Nevertheless there is always only one
owner for them:

After HW readout (booting/system resume):
- encoder->get_power_domains() acquires
- encoder->disable*() releases

After a modeset (calling intel_atomic_commit()):
- encoder->enable*() acquires
- encoder->disable*() releases

* can be any of the encoder enable/disable hooks.

v2:
- Check that the DSI io_wakerefs are unset both during encoder HW
  readout and enabling. (Chris)

Fixes: 0e6e0be4c9523 ("drm/i915: Markup paired operations on display power domains")
Cc: Vandita Kulkarni <vandita.kulkarni@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190407124655.31536-1-imre.deak@intel.com

1 files changed, 8 insertions, 9 deletions

diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index 720de7a3f5e6..0ab3a8a43848 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -2053,12 +2053,11 @@ intel_ddi_main_link_aux_domain(struct intel_digital_port *dig_port)
 					      intel_aux_power_domain(dig_port);
 }
 
-static u64 intel_ddi_get_power_domains(struct intel_encoder *encoder,
-				       struct intel_crtc_state *crtc_state)
+static void intel_ddi_get_power_domains(struct intel_encoder *encoder,
+					struct intel_crtc_state *crtc_state)
 {
 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
 	struct intel_digital_port *dig_port;
-	u64 domains;
 
 	/*
 	 * TODO: Add support for MST encoders. Atm, the following should never
@@ -2066,10 +2065,10 @@ static u64 intel_ddi_get_power_domains(struct intel_encoder *encoder,
 	 * hook.
 	 */
 	if (WARN_ON(intel_crtc_has_type(crtc_state, INTEL_OUTPUT_DP_MST)))
-		return 0;
+		return;
 
 	dig_port = enc_to_dig_port(&encoder->base);
-	domains = BIT_ULL(dig_port->ddi_io_power_domain);
+	intel_display_power_get(dev_priv, dig_port->ddi_io_power_domain);
 
 	/*
 	 * AUX power is only needed for (e)DP mode, and for HDMI mode on TC
@@ -2077,15 +2076,15 @@ static u64 intel_ddi_get_power_domains(struct intel_encoder *encoder,
 	 */
 	if (intel_crtc_has_dp_encoder(crtc_state) ||
 	    intel_port_is_tc(dev_priv, encoder->port))
-		domains |= BIT_ULL(intel_ddi_main_link_aux_domain(dig_port));
+		intel_display_power_get(dev_priv,
+					intel_ddi_main_link_aux_domain(dig_port));
 
 	/*
 	 * VDSC power is needed when DSC is enabled
 	 */
 	if (crtc_state->dsc_params.compression_enable)
-		domains |= BIT_ULL(intel_dsc_power_domain(crtc_state));
-
-	return domains;
+		intel_display_power_get(dev_priv,
+					intel_dsc_power_domain(crtc_state));
 }
 
 void intel_ddi_enable_pipe_clock(const struct intel_crtc_state *crtc_state)