From 7d7fbcdf4e1683d1aef19c7ee08cc222d8279672 Mon Sep 17 00:00:00 2001 From: Eric Anholt Date: Fri, 23 Oct 2015 14:43:41 +0100 Subject: [PATCH] vc4: Add a workaround for HW-2116 (state counter wrap fails). I haven't proven that this happens (I've got other GPU hangs in the way), but the closed driver also does this and it's documented as an errata. --- src/gallium/drivers/vc4/vc4_context.h | 6 +++--- src/gallium/drivers/vc4/vc4_draw.c | 38 +++++++++++++++++++++++++++++++++-- src/gallium/drivers/vc4/vc4_job.c | 2 +- 3 files changed, 40 insertions(+), 6 deletions(-) diff --git a/src/gallium/drivers/vc4/vc4_context.h b/src/gallium/drivers/vc4/vc4_context.h index c769842..7a758f8 100644 --- a/src/gallium/drivers/vc4/vc4_context.h +++ b/src/gallium/drivers/vc4/vc4_context.h @@ -250,10 +250,10 @@ struct vc4_context { bool needs_flush; /** - * Set when needs_flush, and the queued rendering is not just composed - * of full-buffer clears. + * Number of draw calls (not counting full buffer clears) queued in + * the current job. */ - bool draw_call_queued; + uint32_t draw_calls_queued; /** Maximum index buffer valid for the current shader_rec. */ uint32_t max_index; diff --git a/src/gallium/drivers/vc4/vc4_draw.c b/src/gallium/drivers/vc4/vc4_draw.c index c7ca8f9..da81599 100644 --- a/src/gallium/drivers/vc4/vc4_draw.c +++ b/src/gallium/drivers/vc4/vc4_draw.c @@ -100,7 +100,7 @@ vc4_start_draw(struct vc4_context *vc4) VC4_PRIMITIVE_LIST_FORMAT_TYPE_TRIANGLES)); vc4->needs_flush = true; - vc4->draw_call_queued = true; + vc4->draw_calls_queued++; vc4->draw_width = width; vc4->draw_height = height; @@ -226,6 +226,38 @@ vc4_emit_gl_shader_state(struct vc4_context *vc4, const struct pipe_draw_info *i vc4->max_index = max_index; } +/** + * HW-2116 workaround: Flush the batch before triggering the hardware state + * counter wraparound behavior. + * + * State updates are tracked by a global counter which increments at the first + * state update after a draw or a START_BINNING. Tiles can then have their + * state updated at draw time with a set of cheap checks for whether the + * state's copy of the global counter matches the global counter the last time + * that state was written to the tile. + * + * The state counters are relatively small and wrap around quickly, so you + * could get false negatives for needing to update a particular state in the + * tile. To avoid this, the hardware attempts to write all of the state in + * the tile at wraparound time. This apparently is broken, so we just flush + * everything before that behavior is triggered. A batch flush is sufficient + * to get our current contents drawn and reset the counters to 0. + * + * Note that we can't just use VC4_PACKET_FLUSH_ALL, because that caps the + * tiles with VC4_PACKET_RETURN_FROM_LIST. + */ +static void +vc4_hw_2116_workaround(struct pipe_context *pctx) +{ + struct vc4_context *vc4 = vc4_context(pctx); + + if (vc4->draw_calls_queued == 0x1ef0) { + perf_debug("Flushing batch due to HW-2116 workaround " + "(too many draw calls per scene\n"); + vc4_flush(pctx); + } +} + static void vc4_draw_vbo(struct pipe_context *pctx, const struct pipe_draw_info *info) { @@ -244,6 +276,8 @@ vc4_draw_vbo(struct pipe_context *pctx, const struct pipe_draw_info *info) vc4_update_shadow_textures(pctx, &vc4->verttex); vc4_update_shadow_textures(pctx, &vc4->fragtex); + vc4_hw_2116_workaround(pctx); + vc4_get_draw_cl_space(vc4); if (vc4->prim_mode != info->mode) { @@ -343,7 +377,7 @@ vc4_clear(struct pipe_context *pctx, unsigned buffers, /* We can't flag new buffers for clearing once we've queued draws. We * could avoid this by using the 3d engine to clear. */ - if (vc4->draw_call_queued) { + if (vc4->draw_calls_queued) { perf_debug("Flushing rendering to process new clear.\n"); vc4_flush(pctx); } diff --git a/src/gallium/drivers/vc4/vc4_job.c b/src/gallium/drivers/vc4/vc4_job.c index 7ebd9f1..9ad79c2 100644 --- a/src/gallium/drivers/vc4/vc4_job.c +++ b/src/gallium/drivers/vc4/vc4_job.c @@ -55,7 +55,7 @@ vc4_job_reset(struct vc4_context *vc4) vc4->shader_rec_count = 0; vc4->needs_flush = false; - vc4->draw_call_queued = false; + vc4->draw_calls_queued = 0; /* We have no hardware context saved between our draw calls, so we * need to flag the next draw as needing all state emitted. Emitting -- 2.7.4