drm/i915: Keep track of active forcewake domains in a bitmask

There are current places in the code, and there will be more in the
future, which iterate the forcewake domains to find out which ones
are currently active.

To save them from doing this iteration, we can cheaply keep a mask
of active domains in dev_priv->uncore.fw_domains_active.

This has no cost in terms of object size, even manages to shrink it
overall by 368 bytes on my config.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: "Paneri, Praveen" <praveen.paneri@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index dbcac9379ffd27bbcd70d26b924f0bdf799a16ce..925239d1ea395854be93698b0519b92c206c8503 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -588,7 +588,9 @@ struct intel_uncore {
        struct intel_uncore_funcs funcs;
 
        unsigned fifo_count;
+
        enum forcewake_domains fw_domains;
+       enum forcewake_domains fw_domains_active;
 
        struct intel_uncore_forcewake_domain {
                struct drm_i915_private *i915;

diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c
index 18249e35bb02ab50b5c46b4fa703e807b1d0266d..ef40121afbaaf5486d84ff5e577814dde093dde9 100644 (file)
--- a/drivers/gpu/drm/i915/intel_uncore.c
+++ b/drivers/gpu/drm/i915/intel_uncore.c
@@ -231,19 +231,21 @@ intel_uncore_fw_release_timer(struct hrtimer *timer)
 {
        struct intel_uncore_forcewake_domain *domain =
               container_of(timer, struct intel_uncore_forcewake_domain, timer);
+       struct drm_i915_private *dev_priv = domain->i915;
        unsigned long irqflags;
 
-       assert_rpm_device_not_suspended(domain->i915);
+       assert_rpm_device_not_suspended(dev_priv);
 
-       spin_lock_irqsave(&domain->i915->uncore.lock, irqflags);
+       spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
        if (WARN_ON(domain->wake_count == 0))
                domain->wake_count++;
 
-       if (--domain->wake_count == 0)
-               domain->i915->uncore.funcs.force_wake_put(domain->i915,
-                                                         1 << domain->id);
+       if (--domain->wake_count == 0) {
+               dev_priv->uncore.funcs.force_wake_put(dev_priv, domain->mask);
+               dev_priv->uncore.fw_domains_active &= ~domain->mask;
+       }
 
-       spin_unlock_irqrestore(&domain->i915->uncore.lock, irqflags);
+       spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
 
        return HRTIMER_NORESTART;
 }
@@ -254,7 +256,7 @@ void intel_uncore_forcewake_reset(struct drm_i915_private *dev_priv,
        unsigned long irqflags;
        struct intel_uncore_forcewake_domain *domain;
        int retry_count = 100;
-       enum forcewake_domains fw = 0, active_domains;
+       enum forcewake_domains fw, active_domains;
 
        /* Hold uncore.lock across reset to prevent any register access
         * with forcewake not set correctly. Wait until all pending
@@ -291,10 +293,7 @@ void intel_uncore_forcewake_reset(struct drm_i915_private *dev_priv,
 
        WARN_ON(active_domains);
 
-       for_each_fw_domain(domain, dev_priv)
-               if (domain->wake_count)
-                       fw |= domain->mask;
-
+       fw = dev_priv->uncore.fw_domains_active;
        if (fw)
                dev_priv->uncore.funcs.force_wake_put(dev_priv, fw);
 
@@ -443,9 +442,6 @@ static void __intel_uncore_forcewake_get(struct drm_i915_private *dev_priv,
 {
        struct intel_uncore_forcewake_domain *domain;
 
-       if (!dev_priv->uncore.funcs.force_wake_get)
-               return;
-
        fw_domains &= dev_priv->uncore.fw_domains;
 
        for_each_fw_domain_masked(domain, fw_domains, dev_priv) {
@@ -453,8 +449,10 @@ static void __intel_uncore_forcewake_get(struct drm_i915_private *dev_priv,
                        fw_domains &= ~domain->mask;
        }
 
-       if (fw_domains)
+       if (fw_domains) {
                dev_priv->uncore.funcs.force_wake_get(dev_priv, fw_domains);
+               dev_priv->uncore.fw_domains_active |= fw_domains;
+       }
 }
 
 /**
@@ -509,9 +507,6 @@ static void __intel_uncore_forcewake_put(struct drm_i915_private *dev_priv,
 {
        struct intel_uncore_forcewake_domain *domain;
 
-       if (!dev_priv->uncore.funcs.force_wake_put)
-               return;
-
        fw_domains &= dev_priv->uncore.fw_domains;
 
        for_each_fw_domain_masked(domain, fw_domains, dev_priv) {
@@ -567,13 +562,10 @@ void intel_uncore_forcewake_put__locked(struct drm_i915_private *dev_priv,
 
 void assert_forcewakes_inactive(struct drm_i915_private *dev_priv)
 {
-       struct intel_uncore_forcewake_domain *domain;
-
        if (!dev_priv->uncore.funcs.force_wake_get)
                return;
 
-       for_each_fw_domain(domain, dev_priv)
-               WARN_ON(domain->wake_count);
+       WARN_ON(dev_priv->uncore.fw_domains_active);
 }
 
 /* We give fast paths for the really cool registers */
@@ -877,18 +869,18 @@ static inline void __force_wake_auto(struct drm_i915_private *dev_priv,
        if (WARN_ON(!fw_domains))
                return;
 
-       /* Ideally GCC would be constant-fold and eliminate this loop */
-       for_each_fw_domain_masked(domain, fw_domains, dev_priv) {
-               if (domain->wake_count) {
-                       fw_domains &= ~domain->mask;
-                       continue;
-               }
+       /* Turn on all requested but inactive supported forcewake domains. */
+       fw_domains &= dev_priv->uncore.fw_domains;
+       fw_domains &= ~dev_priv->uncore.fw_domains_active;
 
-               fw_domain_arm_timer(domain);
-       }
+       if (fw_domains) {
+               /* Ideally GCC would be constant-fold and eliminate this loop */
+               for_each_fw_domain_masked(domain, fw_domains, dev_priv)
+                       fw_domain_arm_timer(domain);
 
-       if (fw_domains)
                dev_priv->uncore.funcs.force_wake_get(dev_priv, fw_domains);
+               dev_priv->uncore.fw_domains_active |= fw_domains;
+       }
 }
 
 #define __gen6_read(x) \