From: Chris Wilson Date: Tue, 12 Jul 2022 15:21:33 +0000 (+0100) Subject: drm/i915/gt: Serialize TLB invalidates with GT resets X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=33da97894758737895e90c909f16786052680ef4;p=linux.git drm/i915/gt: Serialize TLB invalidates with GT resets Avoid trying to invalidate the TLB in the middle of performing an engine reset, as this may result in the reset timing out. Currently, the TLB invalidate is only serialised by its own mutex, forgoing the uncore lock, but we can take the uncore->lock as well to serialise the mmio access, thereby serialising with the GDRST. Tested on a NUC5i7RYB, BIOS RYBDWi35.86A.0380.2019.0517.1530 with i915 selftest/hangcheck. Cc: stable@vger.kernel.org # v4.4 and upper Fixes: 7938d61591d3 ("drm/i915: Flush TLBs before releasing backing store") Reported-by: Mauro Carvalho Chehab Tested-by: Mauro Carvalho Chehab Reviewed-by: Mauro Carvalho Chehab Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Reviewed-by: Andi Shyti Acked-by: Thomas Hellström Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Rodrigo Vivi Link: https://patchwork.freedesktop.org/patch/msgid/1e59a7c45dd919a530256b9ac721ac6ea86c0677.1657639152.git.mchehab@kernel.org --- diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c b/drivers/gpu/drm/i915/gt/intel_gt.c index 8da3314bb6bf6..68c2b0d8f1876 100644 --- a/drivers/gpu/drm/i915/gt/intel_gt.c +++ b/drivers/gpu/drm/i915/gt/intel_gt.c @@ -952,6 +952,20 @@ void intel_gt_invalidate_tlbs(struct intel_gt *gt) mutex_lock(>->tlb_invalidate_lock); intel_uncore_forcewake_get(uncore, FORCEWAKE_ALL); + spin_lock_irq(&uncore->lock); /* serialise invalidate with GT reset */ + + for_each_engine(engine, gt, id) { + struct reg_and_bit rb; + + rb = get_reg_and_bit(engine, regs == gen8_regs, regs, num); + if (!i915_mmio_reg_offset(rb.reg)) + continue; + + intel_uncore_write_fw(uncore, rb.reg, rb.bit); + } + + spin_unlock_irq(&uncore->lock); + for_each_engine(engine, gt, id) { /* * HW architecture suggest typical invalidation time at 40us, @@ -966,7 +980,6 @@ void intel_gt_invalidate_tlbs(struct intel_gt *gt) if (!i915_mmio_reg_offset(rb.reg)) continue; - intel_uncore_write_fw(uncore, rb.reg, rb.bit); if (__intel_wait_for_register_fw(uncore, rb.reg, rb.bit, 0, timeout_us, timeout_ms,