drm/i915/psr: Avoid initializing PSR if there is no sink support.

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>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180103213824.1405-3-dhinakaran.pandiyan@intel.com

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 6890340..cc659b4 100644 (file)
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -2521,14 +2521,19 @@ 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 df9b1d7..8636503 100644 (file)
--- 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;
+
        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;
+
        /* Per platform default: all disabled. */
        if (i915_modparams.enable_psr == -1)
                i915_modparams.enable_psr = 0;