[Intel-gfx] [PATCH 6/6] drm/i915: Use indirect ctx bb to mend CMD_BUF_CCTL

[Mika Kuoppala]

Use indirect ctx bb to load cmd buffer control value
from context image to avoid corruption.

v2: add to lrc layout (Chris)
v3: end to a cacheline (Chris)

Testcase: igt/i915_selftest/gt_lrc
Signed-off-by: Mika Kuoppala <mika.kuoppala at linux.intel.com>
---
 drivers/gpu/drm/i915/gt/intel_lrc.c     | 99 ++++++++++++++++++++++++-
 drivers/gpu/drm/i915/gt/intel_lrc_reg.h |  1 +
 drivers/gpu/drm/i915/i915_reg.h         |  1 +
 3 files changed, 98 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index e49f0e03e159..e7a94da4da11 100644
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -514,7 +514,7 @@ static void set_offsets(u32 *regs,
 #define REG16(x) \
 	(((x) >> 9) | BIT(7) | BUILD_BUG_ON_ZERO(x >= 0x10000)), \
 	(((x) >> 2) & 0x7f)
-#define END(x) 0, (x)
+#define END(total_state_size) 0, (total_state_size)
 {
 	const u32 base = engine->mmio_base;
 
@@ -922,8 +922,63 @@ static const u8 gen12_rcs_offsets[] = {
 	NOP(6),
 	LRI(1, 0),
 	REG(0x0c8),
+	NOP(3+9+1),
+
+	LRI(51, POSTED),
+	REG16(0x588),
+	REG16(0x588),
+	REG16(0x588),
+	REG16(0x588),
+	REG16(0x588),
+	REG16(0x588),
+	REG(0x028),
+	REG(0x09c),
+	REG(0x0c0),
+	REG(0x178),
+	REG(0x17c),
+	REG16(0x358),
+	REG(0x170),
+	REG(0x150),
+	REG(0x154),
+	REG(0x158),
+	REG16(0x41c),
+	REG16(0x600),
+	REG16(0x604),
+	REG16(0x608),
+	REG16(0x60c),
+	REG16(0x610),
+	REG16(0x614),
+	REG16(0x618),
+	REG16(0x61c),
+	REG16(0x620),
+	REG16(0x624),
+	REG16(0x628),
+	REG16(0x62c),
+	REG16(0x630),
+	REG16(0x634),
+	REG16(0x638),
+	REG16(0x63c),
+	REG16(0x640),
+	REG16(0x644),
+	REG16(0x648),
+	REG16(0x64c),
+	REG16(0x650),
+	REG16(0x654),
+	REG16(0x658),
+	REG16(0x65c),
+	REG16(0x660),
+	REG16(0x664),
+	REG16(0x668),
+	REG16(0x66c),
+	REG16(0x670),
+	REG16(0x674),
+	REG16(0x678),
+	REG16(0x67c),
+	REG(0x068),
+	REG(0x084),
+	NOP(1),
 
-	END(80)
+	END(192)
 };
 
 #undef END
@@ -3198,6 +3253,37 @@ gen12_emit_restore_scratch(struct intel_context *ce, u32 *cs)
 	return cs;
 }
 
+static u32 *
+gen12_emit_cmd_buf_wa(struct intel_context *ce, u32 *cs)
+{
+	const u32 lrc_offset = i915_ggtt_offset(ce->state) +
+		LRC_STATE_OFFSET;
+	const u32 scratch_reg = i915_mmio_reg_offset(GEN8_RING_CS_GPR(0, 0));
+
+	*cs++ = MI_LOAD_REGISTER_MEM_GEN8 |
+		MI_SRM_LRM_GLOBAL_GTT | MI_LRI_LRM_CS_MMIO;
+	*cs++ = scratch_reg;
+	*cs++ = lrc_offset + CTX_CMD_BUF_CCTL * sizeof(u32);
+	*cs++ = 0;
+
+	*cs++ = MI_LOAD_REGISTER_REG |
+		MI_LRR_SOURCE_CS_MMIO | MI_LRI_LRM_CS_MMIO;
+	*cs++ = scratch_reg;
+	*cs++ = i915_mmio_reg_offset(RING_CMD_BUF_CCTL(0));
+
+	return cs;
+}
+
+static u32 *
+gen12_emit_indirect_ctx_rcs(struct intel_context *ce, u32 *cs)
+{
+	cs = gen12_emit_timestamp_wa(ce, cs);
+	cs = gen12_emit_cmd_buf_wa(ce, cs);
+	cs = gen12_emit_restore_scratch(ce, cs);
+
+	return cs;
+}
+
 static u32 *
 gen12_emit_indirect_ctx_xcs(struct intel_context *ce, u32 *cs)
 {
@@ -3282,9 +3368,16 @@ __execlists_update_reg_state(struct intel_context *ce,
 	}
 
 	if (ce->ctx_bb_offset) {
+		u32 *(*fn)(struct intel_context *ce, u32 *cs);
+
+		if (ce->engine->class == RENDER_CLASS)
+			fn = gen12_emit_indirect_ctx_rcs;
+		else
+			fn = gen12_emit_indirect_ctx_xcs;
+
 		/* Mutually exclusive wrt to global indirect bb */
 		GEM_BUG_ON(engine->wa_ctx.indirect_ctx.size);
-		setup_indirect_ctx_bb(ce, gen12_emit_indirect_ctx_xcs);
+		setup_indirect_ctx_bb(ce, fn);
 	}
 }
 
diff --git a/drivers/gpu/drm/i915/gt/intel_lrc_reg.h b/drivers/gpu/drm/i915/gt/intel_lrc_reg.h
index db1f8c24cfe6..382ba539df36 100644
--- a/drivers/gpu/drm/i915/gt/intel_lrc_reg.h
+++ b/drivers/gpu/drm/i915/gt/intel_lrc_reg.h
@@ -31,6 +31,7 @@
 #define CTX_PDP0_LDW			(0x32 + 1)
 #define CTX_R_PWR_CLK_STATE		(0x42 + 1)
 #define CTX_CS_GPR_0			(0x74 + 1)
+#define CTX_CMD_BUF_CCTL		(0xB6 + 1)
 
 #define GEN9_CTX_RING_MI_MODE		0x54
 
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 4a1965467374..0ef30e3cdd3f 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2657,6 +2657,7 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
 #define RING_DMA_FADD_UDW(base)	_MMIO((base) + 0x60) /* gen8+ */
 #define RING_INSTPM(base)	_MMIO((base) + 0xc0)
 #define RING_MI_MODE(base)	_MMIO((base) + 0x9c)
+#define RING_CMD_BUF_CCTL(base) _MMIO((base) + 0x84)
 #define INSTPS		_MMIO(0x2070) /* 965+ only */
 #define GEN4_INSTDONE1	_MMIO(0x207c) /* 965+ only, aka INSTDONE_2 on SNB */
 #define ACTHD_I965	_MMIO(0x2074)
-- 
2.17.1