Now that we can read the CSB from the HWSP, we may avoid having to perform mmio reads entirely and so forgo the rigmarole of the forcewake dance.
Signed-off-by: Chris Wilson <[email protected]> --- drivers/gpu/drm/i915/intel_lrc.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index ff25f209d0a5..7d2df72e68d3 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -778,6 +778,7 @@ static void execlists_submission_tasklet(unsigned long data) struct intel_engine_execlists * const execlists = &engine->execlists; struct execlist_port * const port = execlists->port; struct drm_i915_private *dev_priv = engine->i915; + bool fw = false; /* We can skip acquiring intel_runtime_pm_get() here as it was taken * on our behalf by the request (see i915_gem_mark_busy()) and it will @@ -788,8 +789,6 @@ static void execlists_submission_tasklet(unsigned long data) */ GEM_BUG_ON(!dev_priv->gt.awake); - intel_uncore_forcewake_get(dev_priv, execlists->fw_domains); - /* Prefer doing test_and_clear_bit() as a two stage operation to avoid * imposing the cost of a locked atomic transaction when submitting a * new request (outside of the context-switch interrupt). @@ -818,6 +817,12 @@ static void execlists_submission_tasklet(unsigned long data) */ __clear_bit(ENGINE_IRQ_EXECLIST, &engine->irq_posted); if (unlikely(execlists->csb_head == -1)) { /* following a reset */ + if (!fw) { + intel_uncore_forcewake_get(dev_priv, + execlists->fw_domains); + fw = true; + } + head = readl(dev_priv->regs + i915_mmio_reg_offset(RING_CONTEXT_STATUS_PTR(engine))); tail = GEN8_CSB_WRITE_PTR(head); head = GEN8_CSB_READ_PTR(head); @@ -943,7 +948,8 @@ static void execlists_submission_tasklet(unsigned long data) if (!execlists_is_active(execlists, EXECLISTS_ACTIVE_PREEMPT)) execlists_dequeue(engine); - intel_uncore_forcewake_put(dev_priv, execlists->fw_domains); + if (fw) + intel_uncore_forcewake_put(dev_priv, execlists->fw_domains); } static void insert_request(struct intel_engine_cs *engine, -- 2.15.1 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
