From: Ville Syrjälä <[email protected]> intel_ring_cachline_align() emits MI_NOOPs until the ring tail is aligned to a cacheline boundary.
Cc: Bjoern C <[email protected]> Cc: Alexandru DAMIAN <[email protected]> Cc: Enrico Tagliavini <[email protected]> Suggested-by: Chris Wilson <[email protected]> Signed-off-by: Ville Syrjälä <[email protected]> --- drivers/gpu/drm/i915/intel_ringbuffer.c | 21 +++++++++++++++++++++ drivers/gpu/drm/i915/intel_ringbuffer.h | 1 + 2 files changed, 22 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index ba686d7..8c1c0bc 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -1638,6 +1638,27 @@ int intel_ring_begin(struct intel_ring_buffer *ring, return 0; } +/* Align the ring tail to a cacheline boundary */ +int intel_ring_cacheline_align(struct intel_ring_buffer *ring) +{ + int num_dwords = (64 - (ring->tail & 63)) / sizeof(uint32_t); + int ret; + + if (num_dwords == 0) + return 0; + + ret = intel_ring_begin(ring, num_dwords); + if (ret) + return ret; + + while (num_dwords--) + intel_ring_emit(ring, MI_NOOP); + + intel_ring_advance(ring); + + return 0; +} + void intel_ring_init_seqno(struct intel_ring_buffer *ring, u32 seqno) { struct drm_i915_private *dev_priv = ring->dev->dev_private; diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h index 38c757e..08b91c6 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.h +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h @@ -235,6 +235,7 @@ intel_write_status_page(struct intel_ring_buffer *ring, void intel_cleanup_ring_buffer(struct intel_ring_buffer *ring); int __must_check intel_ring_begin(struct intel_ring_buffer *ring, int n); +int __must_check intel_ring_cacheline_align(struct intel_ring_buffer *ring); static inline void intel_ring_emit(struct intel_ring_buffer *ring, u32 data) { -- 1.8.3.2 _______________________________________________ Intel-gfx mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/intel-gfx
