drm/i915: Remove forced stop ring on suspend/unload

Before suspending (or unloading), we would first wait upon all rendering
to be completed and then disable the rings. This later step is a remanent
from DRI1 days when we did not use request tracking for all operations
upon the ring. Now that we are sure we are waiting upon the very last
operation by the engine, we can forgo clobbering the ring registers,
though we do keep the assert that the engine is indeed idle before
sleeping.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-5-git-send-email-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index db5dc5bd78d83b3d35bfb7c3aa3d492a47fe9a37..abdfb97096e2c1427f14e549e1534797e1bd9263 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2004,7 +2004,6 @@ struct drm_i915_private {
        /* Abstract the submission mechanism (legacy ringbuffer or execlists) away */
        struct {
                void (*cleanup_engine)(struct intel_engine_cs *engine);
-               void (*stop_engine)(struct intel_engine_cs *engine);
 
                /**
                 * Is the GPU currently considered idle, or busy executing

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index cc6d102f1d48c41cb92fc537c39608b0390e438c..395f2ceea8fc24094fea28963b4976b207984881 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -4080,16 +4080,6 @@ struct i915_vma *i915_gem_obj_to_ggtt_view(struct drm_i915_gem_object *obj,
        return NULL;
 }
 
-static void
-i915_gem_stop_engines(struct drm_device *dev)
-{
-       struct drm_i915_private *dev_priv = to_i915(dev);
-       struct intel_engine_cs *engine;
-
-       for_each_engine(engine, dev_priv)
-               dev_priv->gt.stop_engine(engine);
-}
-
 int
 i915_gem_suspend(struct drm_device *dev)
 {
@@ -4118,12 +4108,6 @@ i915_gem_suspend(struct drm_device *dev)
 
        i915_gem_retire_requests(dev_priv);
 
-       /* Note that rather than stopping the engines, all we have to do
-        * is assert that every RING_HEAD == RING_TAIL (all execution complete)
-        * and similar for all logical context images (to ensure they are
-        * all ready for hibernation).
-        */
-       i915_gem_stop_engines(dev);
        i915_gem_context_lost(dev_priv);
        mutex_unlock(&dev->struct_mutex);
 
@@ -4308,10 +4292,8 @@ int i915_gem_init(struct drm_device *dev)
 
        if (!i915.enable_execlists) {
                dev_priv->gt.cleanup_engine = intel_engine_cleanup;
-               dev_priv->gt.stop_engine = intel_engine_stop;
        } else {
                dev_priv->gt.cleanup_engine = intel_logical_ring_cleanup;
-               dev_priv->gt.stop_engine = intel_logical_ring_stop;
        }
 
        /* This is just a security blanket to placate dragons.

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index a07da548ff494029369699fdf771796177470200..309c5d9b1c5724d53303b5db1c9c30fe66301456 100644 (file)
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -760,31 +760,6 @@ void intel_execlists_cancel_requests(struct intel_engine_cs *engine)
        }
 }
 
-void intel_logical_ring_stop(struct intel_engine_cs *engine)
-{
-       struct drm_i915_private *dev_priv = engine->i915;
-       int ret;
-
-       if (!intel_engine_initialized(engine))
-               return;
-
-       ret = intel_engine_idle(engine);
-       if (ret)
-               DRM_ERROR("failed to quiesce %s whilst cleaning up: %d\n",
-                         engine->name, ret);
-
-       /* TODO: Is this correct with Execlists enabled? */
-       I915_WRITE_MODE(engine, _MASKED_BIT_ENABLE(STOP_RING));
-       if (intel_wait_for_register(dev_priv,
-                                   RING_MI_MODE(engine->mmio_base),
-                                   MODE_IDLE, MODE_IDLE,
-                                   1000)) {
-               DRM_ERROR("%s :timed out trying to stop ring\n", engine->name);
-               return;
-       }
-       I915_WRITE_MODE(engine, _MASKED_BIT_DISABLE(STOP_RING));
-}
-
 static int intel_lr_context_pin(struct i915_gem_context *ctx,
                                struct intel_engine_cs *engine)
 {
@@ -1717,7 +1692,6 @@ void intel_logical_ring_cleanup(struct intel_engine_cs *engine)
        dev_priv = engine->i915;
 
        if (engine->buffer) {
-               intel_logical_ring_stop(engine);
                WARN_ON((I915_READ_MODE(engine) & MODE_IDLE) == 0);
        }
 

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index a862234ccf184389449c397ce7856ccadaf8c9ca..4593a65cae846c29f4df365d85d6aed2d857fd97 100644 (file)
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -2203,7 +2203,6 @@ void intel_engine_cleanup(struct intel_engine_cs *engine)
        dev_priv = engine->i915;
 
        if (engine->buffer) {
-               intel_engine_stop(engine);
                WARN_ON(!IS_GEN2(dev_priv) && (I915_READ_MODE(engine) & MODE_IDLE) == 0);
 
                intel_ring_unpin(engine->buffer);
@@ -2907,18 +2906,3 @@ int intel_init_vebox_ring_buffer(struct intel_engine_cs *engine)
 
        return intel_init_ring_buffer(engine);
 }
-
-void intel_engine_stop(struct intel_engine_cs *engine)
-{
-       int ret;
-
-       if (!intel_engine_initialized(engine))
-               return;
-
-       ret = intel_engine_idle(engine);
-       if (ret)
-               DRM_ERROR("failed to quiesce %s whilst cleaning up: %d\n",
-                         engine->name, ret);
-
-       stop_ring(engine);
-}