drm/i915: Use a crtc mask instead of a refcount for dpll functions, v2.

This makes it easier to verify correct dpll setup with only a single crtc.
It is also useful to detect double dpll enable/disable.

Changes since v1:
- Rebase on top of Ander's dpll rework.
- Change debugfs active to a mask.
- Change enabled_crtcs and active_crtcs to unsigned.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1457944075-14123-2-git-send-email-maarten.lankhorst@linux.intel.com
Reviewed-by: Ander Conselvan de Oliveira <conselvan2@gmail.com>

drivers/gpu/drm/i915/i915_debugfs.c

@@ -3212,8 +3212,8 @@ static int i915_shared_dplls_info(struct seq_file *m, void *unused)
 		struct intel_shared_dpll *pll = &dev_priv->shared_dplls[i];
 
 		seq_printf(m, "DPLL%i: %s, id: %i\n", i, pll->name, pll->id);
-		seq_printf(m, " crtc_mask: 0x%08x, active: %d, on: %s\n",
-			   pll->config.crtc_mask, pll->active, yesno(pll->on));
+		seq_printf(m, " crtc_mask: 0x%08x, active: 0x%x, on: %s\n",
+			   pll->config.crtc_mask, pll->active_mask, yesno(pll->on));
 		seq_printf(m, " tracked hardware state:\n");
 		seq_printf(m, " dpll:    0x%08x\n", pll->config.hw_state.dpll);
 		seq_printf(m, " dpll_md: 0x%08x\n",

drivers/gpu/drm/i915/intel_display.c

@@ -12962,7 +12962,7 @@ check_shared_dpll_state(struct drm_device *dev)
 	for (i = 0; i < dev_priv->num_shared_dpll; i++) {
 		struct intel_shared_dpll *pll =
 			intel_get_shared_dpll_by_id(dev_priv, i);
-		int enabled_crtcs = 0, active_crtcs = 0;
+		unsigned enabled_crtcs = 0, active_crtcs = 0;
 		bool active;
 
 		memset(&dpll_hw_state, 0, sizeof(dpll_hw_state));
@@ -12971,15 +12971,15 @@ check_shared_dpll_state(struct drm_device *dev)
 
 		active = pll->funcs.get_hw_state(dev_priv, pll, &dpll_hw_state);
 
-		I915_STATE_WARN(pll->active > hweight32(pll->config.crtc_mask),
-		     "more active pll users than references: %i vs %i\n",
-		     pll->active, hweight32(pll->config.crtc_mask));
-		I915_STATE_WARN(pll->active && !pll->on,
-		     "pll in active use but not on in sw tracking\n");
+		I915_STATE_WARN(pll->active_mask & ~pll->config.crtc_mask,
+		     "more active pll users than references: %x vs %x\n",
+		     pll->active_mask, pll->config.crtc_mask);
 
 		if (!(pll->flags & INTEL_DPLL_ALWAYS_ON)) {
-			I915_STATE_WARN(pll->on && !pll->active,
-			     "pll in on but not on in use in sw tracking\n");
+			I915_STATE_WARN(!pll->on && pll->active_mask,
+			     "pll in active use but not on in sw tracking\n");
+			I915_STATE_WARN(pll->on && !pll->active_mask,
+			     "pll is on but not used by any active crtc\n");
 			I915_STATE_WARN(pll->on != active,
 			     "pll on state mismatch (expected %i, found %i)\n",
 			     pll->on, active);
@@ -12987,16 +12987,17 @@ check_shared_dpll_state(struct drm_device *dev)
 
 		for_each_intel_crtc(dev, crtc) {
 			if (crtc->base.state->enable && crtc->config->shared_dpll == pll)
-				enabled_crtcs++;
-			if (crtc->active && crtc->config->shared_dpll == pll)
-				active_crtcs++;
+				enabled_crtcs |= 1 << drm_crtc_index(&crtc->base);
+			if (crtc->base.state->active && crtc->config->shared_dpll == pll)
+				active_crtcs |= 1 << drm_crtc_index(&crtc->base);
 		}
-		I915_STATE_WARN(pll->active != active_crtcs,
-		     "pll active crtcs mismatch (expected %i, found %i)\n",
-		     pll->active, active_crtcs);
-		I915_STATE_WARN(hweight32(pll->config.crtc_mask) != enabled_crtcs,
-		     "pll enabled crtcs mismatch (expected %i, found %i)\n",
-		     hweight32(pll->config.crtc_mask), enabled_crtcs);
+
+		I915_STATE_WARN(pll->active_mask != active_crtcs,
+		     "pll active crtcs mismatch (expected %x, found %x)\n",
+		     pll->active_mask, active_crtcs);
+		I915_STATE_WARN(pll->config.crtc_mask != enabled_crtcs,
+		     "pll enabled crtcs mismatch (expected %x, found %x)\n",
+		     pll->config.crtc_mask, enabled_crtcs);
 
 		I915_STATE_WARN(pll->on && memcmp(&pll->config.hw_state, &dpll_hw_state,
 				       sizeof(dpll_hw_state)),
@@ -15694,14 +15695,12 @@ static void intel_modeset_readout_hw_state(struct drm_device *dev)
 
 		pll->on = pll->funcs.get_hw_state(dev_priv, pll,
 						  &pll->config.hw_state);
-		pll->active = 0;
 		pll->config.crtc_mask = 0;
 		for_each_intel_crtc(dev, crtc) {
-			if (crtc->active && crtc->config->shared_dpll == pll) {
-				pll->active++;
+			if (crtc->active && crtc->config->shared_dpll == pll)
 				pll->config.crtc_mask |= 1 << crtc->pipe;
-			}
 		}
+		pll->active_mask = pll->config.crtc_mask;
 
 		DRM_DEBUG_KMS("%s hw state readout: crtc_mask 0x%08x, on %i\n",
 			      pll->name, pll->config.crtc_mask, pll->on);
@@ -15825,7 +15824,7 @@ intel_modeset_setup_hw_state(struct drm_device *dev)
 	for (i = 0; i < dev_priv->num_shared_dpll; i++) {
 		struct intel_shared_dpll *pll = &dev_priv->shared_dplls[i];
 
-		if (!pll->on || pll->active)
+		if (!pll->on || pll->active_mask)
 			continue;
 
 		DRM_DEBUG_KMS("%s enabled but not in use, disabling\n", pll->name);

drivers/gpu/drm/i915/intel_dpll_mgr.c

@@ -90,7 +90,7 @@ void intel_prepare_shared_dpll(struct intel_crtc *crtc)
 		return;
 
 	WARN_ON(!pll->config.crtc_mask);
-	if (pll->active == 0) {
+	if (pll->active_mask == 0) {
 		DRM_DEBUG_DRIVER("setting up %s\n", pll->name);
 		WARN_ON(pll->on);
 		assert_shared_dpll_disabled(dev_priv, pll);
@@ -112,18 +112,23 @@ void intel_enable_shared_dpll(struct intel_crtc *crtc)
 	struct drm_device *dev = crtc->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_shared_dpll *pll = crtc->config->shared_dpll;
+	unsigned crtc_mask = 1 << drm_crtc_index(&crtc->base);
+	unsigned old_mask = pll->active_mask;
 
 	if (WARN_ON(pll == NULL))
 		return;
 
-	if (WARN_ON(pll->config.crtc_mask == 0))
+	if (WARN_ON(!(pll->config.crtc_mask & crtc_mask)) ||
+	    WARN_ON(pll->active_mask & crtc_mask))
 		return;
 
-	DRM_DEBUG_KMS("enable %s (active %d, on? %d) for crtc %d\n",
-		      pll->name, pll->active, pll->on,
+	pll->active_mask |= crtc_mask;
+
+	DRM_DEBUG_KMS("enable %s (active %x, on? %d) for crtc %d\n",
+		      pll->name, pll->active_mask, pll->on,
 		      crtc->base.base.id);
 
-	if (pll->active++) {
+	if (old_mask) {
 		WARN_ON(!pll->on);
 		assert_shared_dpll_enabled(dev_priv, pll);
 		return;
@@ -142,6 +147,7 @@ void intel_disable_shared_dpll(struct intel_crtc *crtc)
 	struct drm_device *dev = crtc->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_shared_dpll *pll = crtc->config->shared_dpll;
+	unsigned crtc_mask = 1 << drm_crtc_index(&crtc->base);
 
 	/* PCH only available on ILK+ */
 	if (INTEL_INFO(dev)->gen < 5)
@@ -150,21 +156,18 @@ void intel_disable_shared_dpll(struct intel_crtc *crtc)
 	if (pll == NULL)
 		return;
 
-	if (WARN_ON(!(pll->config.crtc_mask & (1 << drm_crtc_index(&crtc->base)))))
+	if (WARN_ON(!(pll->config.crtc_mask & crtc_mask)))
 		return;
 
-	DRM_DEBUG_KMS("disable %s (active %d, on? %d) for crtc %d\n",
-		      pll->name, pll->active, pll->on,
+	DRM_DEBUG_KMS("disable %s (active %x, on? %d) for crtc %d\n",
+		      pll->name, pll->active_mask, pll->on,
 		      crtc->base.base.id);
 
-	if (WARN_ON(pll->active == 0)) {
-		assert_shared_dpll_disabled(dev_priv, pll);
-		return;
-	}
-
 	assert_shared_dpll_enabled(dev_priv, pll);
 	WARN_ON(!pll->on);
-	if (--pll->active)
+
+	pll->active_mask &= ~crtc_mask;
+	if (pll->active_mask)
 		return;
 
 	DRM_DEBUG_KMS("disabling %s\n", pll->name);
@@ -197,10 +200,10 @@ intel_find_shared_dpll(struct intel_crtc *crtc,
 		if (memcmp(&crtc_state->dpll_hw_state,
 			   &shared_dpll[i].hw_state,
 			   sizeof(crtc_state->dpll_hw_state)) == 0) {
-			DRM_DEBUG_KMS("CRTC:%d sharing existing %s (crtc mask 0x%08x, ative %d)\n",
+			DRM_DEBUG_KMS("CRTC:%d sharing existing %s (crtc mask 0x%08x, active %x)\n",
 				      crtc->base.base.id, pll->name,
 				      shared_dpll[i].crtc_mask,
-				      pll->active);
+				      pll->active_mask);
 			return pll;
 		}
 	}

drivers/gpu/drm/i915/intel_dpll_mgr.h

@@ -115,7 +115,7 @@ struct intel_shared_dpll_funcs {
 struct intel_shared_dpll {
 	struct intel_shared_dpll_config config;
 
-	int active; /* count of number of active CRTCs (i.e. DPMS on) */
+	unsigned active_mask; /* mask of active CRTCs (i.e. DPMS on) */
 	bool on; /* is the PLL actually active? Disabled during modeset */
 	const char *name;
 	/* should match the index in the dev_priv->shared_dplls array */