drm/i915: Try to print INSTDONE bits for all slice/subslice

v2: (Imre)
- Access only subslices that are known to exist.
- Reset explicitly the MCR selector to slice/sub-slice ID 0 after the
  readout.
- Use the subslice INSTDONE bits for the hangcheck/subunits-stuck
  detection too.
- Take the uncore lock for the MCR-select/subslice-readout sequence.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474379673-28326-2-git-send-email-imre.deak@intel.com

drivers/gpu/drm/i915/i915_debugfs.c

@@ -1281,6 +1281,9 @@ static void i915_instdone_info(struct drm_i915_private *dev_priv,
 			       struct seq_file *m,
 			       struct intel_instdone *instdone)
 {
+	int slice;
+	int subslice;
+
 	seq_printf(m, "\t\tINSTDONE: 0x%08x\n",
 		   instdone->instdone);
 
@@ -1293,10 +1296,13 @@ static void i915_instdone_info(struct drm_i915_private *dev_priv,
 	if (INTEL_GEN(dev_priv) <= 6)
 		return;
 
-	seq_printf(m, "\t\tSAMPLER_INSTDONE: 0x%08x\n",
-		   instdone->sampler);
-	seq_printf(m, "\t\tROW_INSTDONE: 0x%08x\n",
-		   instdone->row);
+	for_each_instdone_slice_subslice(dev_priv, slice, subslice)
+		seq_printf(m, "\t\tSAMPLER_INSTDONE[%d][%d]: 0x%08x\n",
+			   slice, subslice, instdone->sampler[slice][subslice]);
+
+	for_each_instdone_slice_subslice(dev_priv, slice, subslice)
+		seq_printf(m, "\t\tROW_INSTDONE[%d][%d]: 0x%08x\n",
+			   slice, subslice, instdone->row[slice][subslice]);
 }
 
 static int i915_hangcheck_info(struct seq_file *m, void *unused)

drivers/gpu/drm/i915/i915_gpu_error.c

@@ -231,6 +231,9 @@ static const char *hangcheck_action_to_str(enum intel_engine_hangcheck_action a)
 static void error_print_instdone(struct drm_i915_error_state_buf *m,
 				 struct drm_i915_error_engine *ee)
 {
+	int slice;
+	int subslice;
+
 	err_printf(m, "  INSTDONE: 0x%08x\n",
 		   ee->instdone.instdone);
 
@@ -243,10 +246,15 @@ static void error_print_instdone(struct drm_i915_error_state_buf *m,
 	if (INTEL_GEN(m->i915) <= 6)
 		return;
 
-	err_printf(m, "  SAMPLER_INSTDONE: 0x%08x\n",
-		   ee->instdone.sampler);
-	err_printf(m, "  ROW_INSTDONE: 0x%08x\n",
-		   ee->instdone.row);
+	for_each_instdone_slice_subslice(m->i915, slice, subslice)
+		err_printf(m, "  SAMPLER_INSTDONE[%d][%d]: 0x%08x\n",
+			   slice, subslice,
+			   ee->instdone.sampler[slice][subslice]);
+
+	for_each_instdone_slice_subslice(m->i915, slice, subslice)
+		err_printf(m, "  ROW_INSTDONE[%d][%d]: 0x%08x\n",
+			   slice, subslice,
+			   ee->instdone.row[slice][subslice]);
 }
 
 static void error_print_engine(struct drm_i915_error_state_buf *m,
@@ -1549,12 +1557,52 @@ const char *i915_cache_level_str(struct drm_i915_private *i915, int type)
 	}
 }
 
+static inline uint32_t
+read_subslice_reg(struct drm_i915_private *dev_priv, int slice,
+		  int subslice, i915_reg_t reg)
+{
+	uint32_t mcr;
+	uint32_t ret;
+	enum forcewake_domains fw_domains;
+
+	fw_domains = intel_uncore_forcewake_for_reg(dev_priv, reg,
+						    FW_REG_READ);
+	fw_domains |= intel_uncore_forcewake_for_reg(dev_priv,
+						     GEN8_MCR_SELECTOR,
+						     FW_REG_READ | FW_REG_WRITE);
+
+	spin_lock_irq(&dev_priv->uncore.lock);
+	intel_uncore_forcewake_get__locked(dev_priv, fw_domains);
+
+	mcr = I915_READ_FW(GEN8_MCR_SELECTOR);
+	/*
+	 * The HW expects the slice and sublice selectors to be reset to 0
+	 * after reading out the registers.
+	 */
+	WARN_ON_ONCE(mcr & (GEN8_MCR_SLICE_MASK | GEN8_MCR_SUBSLICE_MASK));
+	mcr &= ~(GEN8_MCR_SLICE_MASK | GEN8_MCR_SUBSLICE_MASK);
+	mcr |= GEN8_MCR_SLICE(slice) | GEN8_MCR_SUBSLICE(subslice);
+	I915_WRITE_FW(GEN8_MCR_SELECTOR, mcr);
+
+	ret = I915_READ_FW(reg);
+
+	mcr &= ~(GEN8_MCR_SLICE_MASK | GEN8_MCR_SUBSLICE_MASK);
+	I915_WRITE_FW(GEN8_MCR_SELECTOR, mcr);
+
+	intel_uncore_forcewake_put__locked(dev_priv, fw_domains);
+	spin_unlock_irq(&dev_priv->uncore.lock);
+
+	return ret;
+}
+
 /* NB: please notice the memset */
 void i915_get_engine_instdone(struct drm_i915_private *dev_priv,
 			      enum intel_engine_id engine_id,
 			      struct intel_instdone *instdone)
 {
 	u32 mmio_base = dev_priv->engine[engine_id].mmio_base;
+	int slice;
+	int subslice;
 
 	memset(instdone, 0, sizeof(*instdone));
 
@@ -1566,8 +1614,24 @@ void i915_get_engine_instdone(struct drm_i915_private *dev_priv,
 			break;
 
 		instdone->slice_common = I915_READ(GEN7_SC_INSTDONE);
-		instdone->sampler = I915_READ(GEN7_SAMPLER_INSTDONE);
-		instdone->row = I915_READ(GEN7_ROW_INSTDONE);
+		for_each_instdone_slice_subslice(dev_priv, slice, subslice) {
+			instdone->sampler[slice][subslice] =
+				read_subslice_reg(dev_priv, slice, subslice,
+						  GEN7_SAMPLER_INSTDONE);
+			instdone->row[slice][subslice] =
+				read_subslice_reg(dev_priv, slice, subslice,
+						  GEN7_ROW_INSTDONE);
+		}
+		break;
+	case 7:
+		instdone->instdone = I915_READ(RING_INSTDONE(mmio_base));
+
+		if (engine_id != RCS)
+			break;
+
+		instdone->slice_common = I915_READ(GEN7_SC_INSTDONE);
+		instdone->sampler[0][0] = I915_READ(GEN7_SAMPLER_INSTDONE);
+		instdone->row[0][0] = I915_READ(GEN7_ROW_INSTDONE);
 
 		break;
 	case 6:

drivers/gpu/drm/i915/i915_irq.c

@@ -2549,6 +2549,9 @@ static inline void
 i915_err_print_instdone(struct drm_i915_private *dev_priv,
 			struct intel_instdone *instdone)
 {
+	int slice;
+	int subslice;
+
 	pr_err("  INSTDONE: 0x%08x\n", instdone->instdone);
 
 	if (INTEL_GEN(dev_priv) <= 3)
@@ -2559,8 +2562,13 @@ i915_err_print_instdone(struct drm_i915_private *dev_priv,
 	if (INTEL_GEN(dev_priv) <= 6)
 		return;
 
-	pr_err("  SAMPLER_INSTDONE: 0x%08x\n", instdone->sampler);
-	pr_err("  ROW_INSTDONE: 0x%08x\n", instdone->row);
+	for_each_instdone_slice_subslice(dev_priv, slice, subslice)
+		pr_err("  SAMPLER_INSTDONE[%d][%d]: 0x%08x\n",
+		       slice, subslice, instdone->sampler[slice][subslice]);
+
+	for_each_instdone_slice_subslice(dev_priv, slice, subslice)
+		pr_err("  ROW_INSTDONE[%d][%d]: 0x%08x\n",
+		       slice, subslice, instdone->row[slice][subslice]);
 }
 
 static void i915_report_and_clear_eir(struct drm_i915_private *dev_priv)
@@ -2981,6 +2989,8 @@ static bool subunits_stuck(struct intel_engine_cs *engine)
 	struct intel_instdone instdone;
 	struct intel_instdone *accu_instdone = &engine->hangcheck.instdone;
 	bool stuck;
+	int slice;
+	int subslice;
 
 	if (engine->id != RCS)
 		return true;
@@ -2996,10 +3006,13 @@ static bool subunits_stuck(struct intel_engine_cs *engine)
 				   &accu_instdone->instdone);
 	stuck &= instdone_unchanged(instdone.slice_common,
 				    &accu_instdone->slice_common);
-	stuck &= instdone_unchanged(instdone.sampler,
-				    &accu_instdone->sampler);
-	stuck &= instdone_unchanged(instdone.row,
-				    &accu_instdone->row);
+
+	for_each_instdone_slice_subslice(dev_priv, slice, subslice) {
+		stuck &= instdone_unchanged(instdone.sampler[slice][subslice],
+					    &accu_instdone->sampler[slice][subslice]);
+		stuck &= instdone_unchanged(instdone.row[slice][subslice],
+					    &accu_instdone->row[slice][subslice]);
+	}
 
 	return stuck;
 }

drivers/gpu/drm/i915/i915_reg.h

@@ -1708,6 +1708,11 @@ enum skl_disp_power_wells {
 #define GEN7_SC_INSTDONE	_MMIO(0x7100)
 #define GEN7_SAMPLER_INSTDONE	_MMIO(0xe160)
 #define GEN7_ROW_INSTDONE	_MMIO(0xe164)
+#define GEN8_MCR_SELECTOR		_MMIO(0xfdc)
+#define   GEN8_MCR_SLICE(slice)		(((slice) & 3) << 26)
+#define   GEN8_MCR_SLICE_MASK		GEN8_MCR_SLICE(3)
+#define   GEN8_MCR_SUBSLICE(subslice)	(((subslice) & 3) << 24)
+#define   GEN8_MCR_SUBSLICE_MASK	GEN8_MCR_SUBSLICE(3)
 #define RING_IPEIR(base)	_MMIO((base)+0x64)
 #define RING_IPEHR(base)	_MMIO((base)+0x68)
 /*

drivers/gpu/drm/i915/intel_ringbuffer.h

@@ -73,12 +73,31 @@ enum intel_engine_hangcheck_action {
 
 #define HANGCHECK_SCORE_RING_HUNG 31
 
+#define I915_MAX_SLICES	3
+#define I915_MAX_SUBSLICES 3
+
+#define instdone_slice_mask(dev_priv__) \
+	(INTEL_GEN(dev_priv__) == 7 ? \
+	 1 : INTEL_INFO(dev_priv__)->sseu.slice_mask)
+
+#define instdone_subslice_mask(dev_priv__) \
+	(INTEL_GEN(dev_priv__) == 7 ? \
+	 1 : INTEL_INFO(dev_priv__)->sseu.subslice_mask)
+
+#define for_each_instdone_slice_subslice(dev_priv__, slice__, subslice__) \
+	for ((slice__) = 0, (subslice__) = 0; \
+	     (slice__) < I915_MAX_SLICES; \
+	     (subslice__) = ((subslice__) + 1) < I915_MAX_SUBSLICES ? (subslice__) + 1 : 0, \
+	       (slice__) += ((subslice__) == 0)) \
+		for_each_if((BIT(slice__) & instdone_slice_mask(dev_priv__)) && \
+			    (BIT(subslice__) & instdone_subslice_mask(dev_priv__)))
+
 struct intel_instdone {
 	u32 instdone;
 	/* The following exist only in the RCS engine */
 	u32 slice_common;
-	u32 sampler;
-	u32 row;
+	u32 sampler[I915_MAX_SLICES][I915_MAX_SUBSLICES];
+	u32 row[I915_MAX_SLICES][I915_MAX_SUBSLICES];
 };
 
 struct intel_engine_hangcheck {