drm/i915: Add debugfs entry for DRRS

Adding a debugfs entry to determine if DRRS is supported or not

V2: [By Ram]: Following details about the active crtc will be filled
	in seq-file of the debugfs
	1. Encoder output type
	2. DRRS Support on this CRTC
	3. DRRS current state
	4. Current Vrefresh
Format is as follows:
CRTC 1:  Output: eDP, DRRS Supported: Yes (Seamless), DRRS_State: DRRS_HIGH_RR, Vrefresh: 60
CRTC 2:  Output: HDMI, DRRS Supported : No, VBT DRRS_type: Seamless
CRTC 1:  Output: eDP, DRRS Supported: Yes (Seamless), DRRS_State: DRRS_LOW_RR, Vrefresh: 40
CRTC 2:  Output: HDMI, DRRS Supported : No, VBT DRRS_type: Seamless

V3: [By Ram]: Readability is improved.
	Another error case is covered [Daniel]

V4: [By Ram]: Current status of the Idleness DRRS along with
	the Front buffer bits are added to the debugfs. [Rodrigo]

V5: [By Ram]: Rephrased to make it easy to understand.
	And format is modified. [Rodrigo]

V6: [By Ram]: Modeset mutex are acquired for each crtc along with
	renaming the Idleness detection states  [Daniel]

Signed-off-by: Vandana Kannan <vandana.kannan@intel.com>
Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
[danvet: dump full busy_frontbuffer_bits and remove the dubios
computed logical state of DRRS - debugfs is about what is fact,
developers should reach their own conclusion when debugging issues.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 63aa721..e14b447 100644 (file)
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -2870,6 +2870,115 @@ static int i915_ddb_info(struct seq_file *m, void *unused)
        return 0;
 }
 
+static void drrs_status_per_crtc(struct seq_file *m,
+               struct drm_device *dev, struct intel_crtc *intel_crtc)
+{
+       struct intel_encoder *intel_encoder;
+       struct drm_i915_private *dev_priv = dev->dev_private;
+       struct i915_drrs *drrs = &dev_priv->drrs;
+       int vrefresh = 0;
+
+       for_each_encoder_on_crtc(dev, &intel_crtc->base, intel_encoder) {
+               /* Encoder connected on this CRTC */
+               switch (intel_encoder->type) {
+               case INTEL_OUTPUT_EDP:
+                       seq_puts(m, "eDP:\n");
+                       break;
+               case INTEL_OUTPUT_DSI:
+                       seq_puts(m, "DSI:\n");
+                       break;
+               case INTEL_OUTPUT_HDMI:
+                       seq_puts(m, "HDMI:\n");
+                       break;
+               case INTEL_OUTPUT_DISPLAYPORT:
+                       seq_puts(m, "DP:\n");
+                       break;
+               default:
+                       seq_printf(m, "Other encoder (id=%d).\n",
+                                               intel_encoder->type);
+                       return;
+               }
+       }
+
+       if (dev_priv->vbt.drrs_type == STATIC_DRRS_SUPPORT)
+               seq_puts(m, "\tVBT: DRRS_type: Static");
+       else if (dev_priv->vbt.drrs_type == SEAMLESS_DRRS_SUPPORT)
+               seq_puts(m, "\tVBT: DRRS_type: Seamless");
+       else if (dev_priv->vbt.drrs_type == DRRS_NOT_SUPPORTED)
+               seq_puts(m, "\tVBT: DRRS_type: None");
+       else
+               seq_puts(m, "\tVBT: DRRS_type: FIXME: Unrecognized Value");
+
+       seq_puts(m, "\n\n");
+
+       if (intel_crtc->config->has_drrs) {
+               struct intel_panel *panel;
+
+               mutex_lock(&drrs->mutex);
+               /* DRRS Supported */
+               seq_puts(m, "\tDRRS Supported: Yes\n");
+
+               /* disable_drrs() will make drrs->dp NULL */
+               if (!drrs->dp) {
+                       seq_puts(m, "Idleness DRRS: Disabled");
+                       mutex_unlock(&drrs->mutex);
+                       return;
+               }
+
+               panel = &drrs->dp->attached_connector->panel;
+               seq_printf(m, "\t\tBusy_frontbuffer_bits: 0x%X",
+                                       drrs->busy_frontbuffer_bits);
+
+               seq_puts(m, "\n\t\t");
+               if (drrs->refresh_rate_type == DRRS_HIGH_RR) {
+                       seq_puts(m, "DRRS_State: DRRS_HIGH_RR\n");
+                       vrefresh = panel->fixed_mode->vrefresh;
+               } else if (drrs->refresh_rate_type == DRRS_LOW_RR) {
+                       seq_puts(m, "DRRS_State: DRRS_LOW_RR\n");
+                       vrefresh = panel->downclock_mode->vrefresh;
+               } else {
+                       seq_printf(m, "DRRS_State: Unknown(%d)\n",
+                                               drrs->refresh_rate_type);
+                       mutex_unlock(&drrs->mutex);
+                       return;
+               }
+               seq_printf(m, "\t\tVrefresh: %d", vrefresh);
+
+               seq_puts(m, "\n\t\t");
+               mutex_unlock(&drrs->mutex);
+       } else {
+               /* DRRS not supported. Print the VBT parameter*/
+               seq_puts(m, "\tDRRS Supported : No");
+       }
+       seq_puts(m, "\n");
+}
+
+static int i915_drrs_status(struct seq_file *m, void *unused)
+{
+       struct drm_info_node *node = m->private;
+       struct drm_device *dev = node->minor->dev;
+       struct intel_crtc *intel_crtc;
+       int active_crtc_cnt = 0;
+
+       for_each_intel_crtc(dev, intel_crtc) {
+               drm_modeset_lock(&intel_crtc->base.mutex, NULL);
+
+               if (intel_crtc->active) {
+                       active_crtc_cnt++;
+                       seq_printf(m, "\nCRTC %d:  ", active_crtc_cnt);
+
+                       drrs_status_per_crtc(m, dev, intel_crtc);
+               }
+
+               drm_modeset_unlock(&intel_crtc->base.mutex);
+       }
+
+       if (!active_crtc_cnt)
+               seq_puts(m, "No active crtc found\n");
+
+       return 0;
+}
+
 struct pipe_crc_info {
        const char *name;
        struct drm_device *dev;
@@ -4548,6 +4657,7 @@ static const struct drm_info_list i915_debugfs_list[] = {
        {"i915_wa_registers", i915_wa_registers, 0},
        {"i915_ddb_info", i915_ddb_info, 0},
        {"i915_sseu_status", i915_sseu_status, 0},
+       {"i915_drrs_status", i915_drrs_status, 0},
 };
 #define I915_DEBUGFS_ENTRIES ARRAY_SIZE(i915_debugfs_list)