[Intel-gfx] [PATCH] drm/i915: Fix indirect context size calculation

[Mika Kuoppala]

Hardware needs cacheline count for indirect context size.
Count of zero means that the feature is disabled.
If we only divide size with cacheline bytes, we get
one cacheline short of execution.

Divide by rounding up to a cacheline size so that
hardware executes everything intended.

Bspec: 11739
Fixes: 17ee950df38b ("drm/i915/gen8: Add infrastructure to initialize WA batch buffers")
Cc: Chris Wilson <chris at chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala at linux.intel.com>
---
 drivers/gpu/drm/i915/gt/intel_lrc.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index 6fbad5e2343f..acbb36ad17ff 100644
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -4739,7 +4739,8 @@ static void init_wa_bb_reg_state(u32 * const regs,
 
 		regs[pos_bb_per_ctx + 2] =
 			(ggtt_offset + wa_ctx->indirect_ctx.offset) |
-			(wa_ctx->indirect_ctx.size / CACHELINE_BYTES);
+			DIV_ROUND_UP(wa_ctx->indirect_ctx.size,
+				     CACHELINE_BYTES);
 
 		regs[pos_bb_per_ctx + 4] =
 			intel_lr_indirect_ctx_offset(engine) << 6;
-- 
2.17.1