drm/i915: Apply strongly ordered RCS breadcrumb to gen8/legacy

For legacy ringbuffer mode, we need the new ordered breadcrumb emission
tried and tested on execlists in order to avoid the dreaded "missed
interrupt" syndrome. A secondary advantage of the execlists method is
that it writes to an arbitrary address, useful if one wants to write a
breadcrumb elsewhere.

This fix is taken from commit 7c17d37737 (drm/i915: Use ordered seqno
write interrupt generation on gen8+ execlists).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1461932305-14637-1-git-send-email-chris@chris-wilson.co.uk
This commit is contained in:
Chris Wilson 2016-04-29 13:18:21 +01:00
parent 0e93cdd4a9
commit a58c01aa6e
3 changed files with 38 additions and 9 deletions

View File

@ -1767,11 +1767,6 @@ static void bxt_a_set_seqno(struct intel_engine_cs *engine, u32 seqno)
*/
#define WA_TAIL_DWORDS 2
static inline u32 hws_seqno_address(struct intel_engine_cs *engine)
{
return engine->status_page.gfx_addr + I915_GEM_HWS_INDEX_ADDR;
}
static int gen8_emit_request(struct drm_i915_gem_request *request)
{
struct intel_ringbuffer *ringbuf = request->ringbuf;
@ -1787,7 +1782,7 @@ static int gen8_emit_request(struct drm_i915_gem_request *request)
intel_logical_ring_emit(ringbuf,
(MI_FLUSH_DW + 1) | MI_FLUSH_DW_OP_STOREDW);
intel_logical_ring_emit(ringbuf,
hws_seqno_address(request->engine) |
intel_hws_seqno_address(request->engine) |
MI_FLUSH_DW_USE_GTT);
intel_logical_ring_emit(ringbuf, 0);
intel_logical_ring_emit(ringbuf, i915_gem_request_get_seqno(request));
@ -1817,7 +1812,8 @@ static int gen8_emit_request_render(struct drm_i915_gem_request *request)
(PIPE_CONTROL_GLOBAL_GTT_IVB |
PIPE_CONTROL_CS_STALL |
PIPE_CONTROL_QW_WRITE));
intel_logical_ring_emit(ringbuf, hws_seqno_address(request->engine));
intel_logical_ring_emit(ringbuf,
intel_hws_seqno_address(request->engine));
intel_logical_ring_emit(ringbuf, 0);
intel_logical_ring_emit(ringbuf, i915_gem_request_get_seqno(request));
/* We're thrashing one dword of HWS. */

View File

@ -1430,6 +1430,35 @@ gen6_add_request(struct drm_i915_gem_request *req)
return 0;
}
static int
gen8_render_add_request(struct drm_i915_gem_request *req)
{
struct intel_engine_cs *engine = req->engine;
int ret;
if (engine->semaphore.signal)
ret = engine->semaphore.signal(req, 8);
else
ret = intel_ring_begin(req, 8);
if (ret)
return ret;
intel_ring_emit(engine, GFX_OP_PIPE_CONTROL(6));
intel_ring_emit(engine, (PIPE_CONTROL_GLOBAL_GTT_IVB |
PIPE_CONTROL_CS_STALL |
PIPE_CONTROL_QW_WRITE));
intel_ring_emit(engine, intel_hws_seqno_address(req->engine));
intel_ring_emit(engine, 0);
intel_ring_emit(engine, i915_gem_request_get_seqno(req));
/* We're thrashing one dword of HWS. */
intel_ring_emit(engine, 0);
intel_ring_emit(engine, MI_USER_INTERRUPT);
intel_ring_emit(engine, MI_NOOP);
__intel_ring_advance(engine);
return 0;
}
static inline bool i915_gem_has_seqno_wrapped(struct drm_device *dev,
u32 seqno)
{
@ -2751,12 +2780,11 @@ int intel_init_render_ring_buffer(struct drm_device *dev)
}
engine->init_context = intel_rcs_ctx_init;
engine->add_request = gen6_add_request;
engine->add_request = gen8_render_add_request;
engine->flush = gen8_render_ring_flush;
engine->irq_get = gen8_ring_get_irq;
engine->irq_put = gen8_ring_put_irq;
engine->irq_enable_mask = GT_RENDER_USER_INTERRUPT;
engine->irq_seqno_barrier = gen6_seqno_barrier;
engine->get_seqno = ring_get_seqno;
engine->set_seqno = ring_set_seqno;
if (i915_semaphore_is_enabled(dev)) {

View File

@ -489,4 +489,9 @@ static inline u32 intel_ring_get_tail(struct intel_ringbuffer *ringbuf)
*/
#define MIN_SPACE_FOR_ADD_REQUEST 336
static inline u32 intel_hws_seqno_address(struct intel_engine_cs *engine)
{
return engine->status_page.gfx_addr + I915_GEM_HWS_INDEX_ADDR;
}
#endif /* _INTEL_RINGBUFFER_H_ */