| Message ID | 1435676471-30925-2-git-send-email-david.s.gordon@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Jun 30, 2015 at 04:01:11PM +0100, Dave Gordon wrote: > We can do less work during driver load by deferring some of it until > the first time the device is opened; in particular, the function > i915_gem_init_hw_late() introduced by the previous patch. This should > allow the system to get out of the early single-threaded phase of > system initialisation and into full multi-user mode somewhat quicker. > > In addition, we expect that by the time of the first open, not only > the driver's software structures but also system-specific items such > as filesystem mounting have been fully initialised, meaning that the > late initialisation code can run in a much more complete environment > than the driver_load stage presents. This can be important for > embedded programmable devices that need firmware loaded from a file > before they can be used. No. It delays establising the power contexts. Something that in the past we have been told must be done asap. You can move it to an async worker, that would be achieve the goals stated here, and not be dependent on a cooperating userspace. -Chris
Tested-By: Intel Graphics QA PRTS (Patch Regression Test System Contact: shuang.he@intel.com)
Task id: 6687
-------------------------------------Summary-------------------------------------
Platform Delta drm-intel-nightly Series Applied
ILK 302/302 302/302
SNB 312/316 312/316
IVB 343/343 343/343
BYT -1 287/287 286/287
HSW 380/380 380/380
-------------------------------------Detailed-------------------------------------
Platform Test drm-intel-nightly Series Applied
*BYT igt@gem_partial_pwrite_pread@reads-display PASS(1) FAIL(1)
Note: You need to pay more attention to line start with '*'
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index bc7c510..ba63804 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1845,6 +1845,7 @@ struct drm_i915_private { /* hda/i915 audio component */ bool audio_component_registered; + bool contexts_ready; uint32_t hw_context_size; struct list_head context_list; diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 1887e60..0cb962f 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -5073,7 +5073,9 @@ i915_gem_init_hw(struct drm_device *dev) goto out; } - ret = i915_gem_init_hw_late(dev); + /* Don't do late init on the first time through here */ + if (dev_priv->contexts_ready) + ret = i915_gem_init_hw_late(dev); out: intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL); diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c index a7e58a8..917c867 100644 --- a/drivers/gpu/drm/i915/i915_gem_context.c +++ b/drivers/gpu/drm/i915/i915_gem_context.c @@ -438,23 +438,45 @@ static int context_idr_cleanup(int id, void *p, void *data) return 0; } +/* Complete any late initialisation here */ +static int i915_gem_context_first_open(struct drm_device *dev) +{ + struct drm_i915_private *dev_priv = dev->dev_private; + int ret; + + ret = i915_gem_init_hw_late(dev); + if (ret == 0) + dev_priv->contexts_ready = true; + + return ret; +} + int i915_gem_context_open(struct drm_device *dev, struct drm_file *file) { + struct drm_i915_private *dev_priv = dev->dev_private; struct drm_i915_file_private *file_priv = file->driver_priv; struct intel_context *ctx; + int ret = 0; idr_init(&file_priv->context_idr); mutex_lock(&dev->struct_mutex); - ctx = i915_gem_create_context(dev, file_priv); + + if (!dev_priv->contexts_ready) + ret = i915_gem_context_first_open(dev); + + if (ret == 0) { + ctx = i915_gem_create_context(dev, file_priv); + if (IS_ERR(ctx)) + ret = PTR_ERR(ctx); + } + mutex_unlock(&dev->struct_mutex); - if (IS_ERR(ctx)) { + if (ret) idr_destroy(&file_priv->context_idr); - return PTR_ERR(ctx); - } - return 0; + return ret; } void i915_gem_context_close(struct drm_device *dev, struct drm_file *file)
We can do less work during driver load by deferring some of it until the first time the device is opened; in particular, the function i915_gem_init_hw_late() introduced by the previous patch. This should allow the system to get out of the early single-threaded phase of system initialisation and into full multi-user mode somewhat quicker. In addition, we expect that by the time of the first open, not only the driver's software structures but also system-specific items such as filesystem mounting have been fully initialised, meaning that the late initialisation code can run in a much more complete environment than the driver_load stage presents. This can be important for embedded programmable devices that need firmware loaded from a file before they can be used. Signed-off-by: Dave Gordon <david.s.gordon@intel.com> --- drivers/gpu/drm/i915/i915_drv.h | 1 + drivers/gpu/drm/i915/i915_gem.c | 4 +++- drivers/gpu/drm/i915/i915_gem_context.c | 32 ++++++++++++++++++++++++++----- 3 files changed, 31 insertions(+), 6 deletions(-)