Re: [PATCH v2 3/8] drm/i915/psr: Avoid initializing PSR if there is no sink support.

On Tue, Dec 19, 2017 at 05:26:54AM +0000, Dhinakaran Pandiyan wrote:

DPCD read for the eDP is complete by the time intel_psr_init() is called, which means we can avoid initializing PSR structures and state if there is no sink support.

Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: Ville Syrjälä ville.syrjala@linux.intel.com Signed-off-by: Dhinakaran Pandiyan dhinakaran.pandiyan@intel.com

---

drivers/gpu/drm/i915/i915_debugfs.c | 7 ++++++- drivers/gpu/drm/i915/intel_psr.c | 9 +++++++++ 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index 64e5a263458c..1a7b28f62570 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -2532,14 +2532,19 @@ static int i915_edp_psr_status(struct seq_file *m, void *data) u32 stat[3]; enum pipe pipe; bool enabled = false;

• bool sink_support;

  if (!HAS_PSR(dev_priv)) return -ENODEV;

• sink_support = dev_priv->psr.sink_support;

• seq_printf(m, "Sink_Support: %s\n", yesno(sink_support));

• if (!sink_support)

• return 0;
  

• intel_runtime_pm_get(dev_priv);

  mutex_lock(&dev_priv->psr.lock);

• seq_printf(m, "Sink_Support: %s\n", yesno(dev_priv->psr.sink_support)); seq_printf(m, "Enabled: %s\n", yesno((bool)dev_priv->psr.enabled)); seq_printf(m, "Active: %s\n", yesno(dev_priv->psr.active)); seq_printf(m, "Busy frontbuffer bits: 0x%03x\n",

diff --git a/drivers/gpu/drm/i915/intel_psr.c b/drivers/gpu/drm/i915/intel_psr.c index 76339cf387cb..095e0a5a8574 100644 --- a/drivers/gpu/drm/i915/intel_psr.c +++ b/drivers/gpu/drm/i915/intel_psr.c @@ -503,6 +503,9 @@ void intel_psr_enable(struct intel_dp *intel_dp, if (!crtc_state->has_psr) return;

• if (WARN_ON(!CAN_PSR(dev_priv)))

• return;
  

hmm... I believe we will see this warning sooner than later...

has_psr is not the same as CAN_PSR.

also, btw I didn't like all this crtc_state has_psr x has_psr2. :/

probably this series could also unify that and clean it up. to many has_psr like cases.

• WARN_ON(dev_priv->drrs.dp); mutex_lock(&dev_priv->psr.lock); if (dev_priv->psr.enabled) {

@@ -633,6 +636,9 @@ void intel_psr_disable(struct intel_dp *intel_dp, if (!old_crtc_state->has_psr) return;

• if (WARN_ON(!CAN_PSR(dev_priv)))

• return;
  

• mutex_lock(&dev_priv->psr.lock); if (!dev_priv->psr.enabled) { mutex_unlock(&dev_priv->psr.lock);

@@ -913,6 +919,9 @@ void intel_psr_init(struct drm_i915_private *dev_priv) dev_priv->psr_mmio_base = IS_HASWELL(dev_priv) ? HSW_EDP_PSR_BASE : BDW_EDP_PSR_BASE;

• if (!dev_priv->psr.sink_support)

• return;
  

Why not use CAN_PSR here?

/* Per platform default: all disabled. */ if (i915_modparams.enable_psr == -1) i915_modparams.enable_psr = 0; -- 2.11.0