drm/i915/gen9: Remove csr.state, csr_lock and related code.
This removes two anti-patterns:
- Locking shouldn't be used to synchronize with async work (of any
form, whether callbacks, workers or other threads). This is what the
mutex_lock/unlock seems to have been for in intel_csr_load_program.
Instead ordering should be ensured with the generic
wait_for_completion()/complete(). Or more specific functions
provided by the core kernel like e.g.
flush_work()/cancel_work_sync() in the case of synchronizing with a
work item.
- Don't invent own completion like the following code did with the
(already removed) wait_for(csr_load_status_get()) pattern - it's
really hard to get these right when you want them to be _really_
correct (and be fast) in all cases. Furthermore it's easier to read
code using the well-known primitives than new ones using
non-standard names.
Before enabling/disabling DC6 check if the firmware is loaded
successfully. This is guaranteed during runtime s/r, since otherwise we
don't enable RPM, but not during system s/r.
Note that it's still unclear whether we need to enable/disable DC6
during system s/r, until that's clarified, keep the current behavior and
enable/disable DC6.
Also after this patch there is a race during system s/r where the
firmware may not be loaded yet, that's addressed in an upcoming patch.
v2-v3:
- unchanged
v4:
- rebased on latest drm-intel-nightly
Cc: Damien Lespiau <damien.lespiau@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
[imre: added code and note about checking if the firmware loaded ok,
before enabling/disabling it]
Reviewed-by: Animesh Manna <animesh.manna@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Tested-by: Daniel Stone <daniels@collabora.com> # SKL
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447341037-2623-1-git-send-email-imre.deak@intel.com
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 9f55209..aa34fcb 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1087,18 +1087,11 @@
static int skl_suspend_complete(struct drm_i915_private *dev_priv)
{
- enum csr_state state;
/* Enabling DC6 is not a hard requirement to enter runtime D3 */
skl_uninit_cdclk(dev_priv);
- /* TODO: wait for a completion event or
- * similar here instead of busy
- * waiting using wait_for function.
- */
- wait_for((state = intel_csr_load_status_get(dev_priv)) !=
- FW_UNINITIALIZED, 1000);
- if (state == FW_LOADED)
+ if (dev_priv->csr.dmc_payload)
skl_enable_dc6(dev_priv);
return 0;
@@ -1147,7 +1140,7 @@
{
struct drm_device *dev = dev_priv->dev;
- if (intel_csr_load_status_get(dev_priv) == FW_LOADED)
+ if (dev_priv->csr.dmc_payload)
skl_disable_dc6(dev_priv);
skl_init_cdclk(dev_priv);