[Intel-gfx] [PATCH 2/9] drm/i915: add HAS_FORCEWAKE flag to uncore

[Daniele Ceraolo Spurio]

We have several cases where we don't have forcewake (older gens, GVT and
planned display-only uncore), so, instead of checking every time against
the various condition, save the info in a flag and use that.

Note that this patch also change the behavior for gen5 with vpgu
enabled, but this is not an issue since we don't support vgpu on gen5.

v2: split out from previous path, fix check for missing case (Paulo)

Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni at intel.com>
Cc: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/intel_uncore.c | 31 +++++++++++++++++++----------
 drivers/gpu/drm/i915/intel_uncore.h |  3 +++
 2 files changed, 24 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c
index 3f74889c4212..0259a61a745f 100644
--- a/drivers/gpu/drm/i915/intel_uncore.c
+++ b/drivers/gpu/drm/i915/intel_uncore.c
@@ -1391,7 +1391,7 @@ static void intel_uncore_fw_domains_init(struct intel_uncore *uncore)
 {
 	struct drm_i915_private *i915 = uncore_to_i915(uncore);
 
-	if (INTEL_GEN(i915) <= 5 || intel_vgpu_active(i915))
+	if (!(uncore->flags & UNCORE_HAS_FORCEWAKE))
 		return;
 
 	if (INTEL_GEN(i915) >= 11) {
@@ -1590,6 +1590,9 @@ int intel_uncore_init(struct intel_uncore *uncore)
 
 	i915_check_vgpu(i915);
 
+	if (INTEL_GEN(i915) > 5 && !intel_vgpu_active(i915))
+		uncore->flags |= UNCORE_HAS_FORCEWAKE;
+
 	intel_uncore_edram_detect(i915);
 	intel_uncore_fw_domains_init(uncore);
 	__intel_uncore_early_sanitize(uncore, 0);
@@ -1598,12 +1601,14 @@ int intel_uncore_init(struct intel_uncore *uncore)
 	uncore->pmic_bus_access_nb.notifier_call =
 		i915_pmic_bus_access_notifier;
 
-	if (IS_GEN_RANGE(i915, 2, 4) || intel_vgpu_active(i915)) {
-		ASSIGN_WRITE_MMIO_VFUNCS(uncore, gen2);
-		ASSIGN_READ_MMIO_VFUNCS(uncore, gen2);
-	} else if (IS_GEN(i915, 5)) {
-		ASSIGN_WRITE_MMIO_VFUNCS(uncore, gen5);
-		ASSIGN_READ_MMIO_VFUNCS(uncore, gen5);
+	if (!(uncore->flags & UNCORE_HAS_FORCEWAKE)) {
+		if (IS_GEN(i915, 5)) {
+			ASSIGN_WRITE_MMIO_VFUNCS(uncore, gen5);
+			ASSIGN_READ_MMIO_VFUNCS(uncore, gen5);
+		} else {
+			ASSIGN_WRITE_MMIO_VFUNCS(uncore, gen2);
+			ASSIGN_READ_MMIO_VFUNCS(uncore, gen2);
+		}
 	} else if (IS_GEN_RANGE(i915, 6, 7)) {
 		ASSIGN_WRITE_MMIO_VFUNCS(uncore, gen6);
 
@@ -1912,7 +1917,10 @@ intel_uncore_forcewake_for_read(struct drm_i915_private *dev_priv,
 	} else if (INTEL_GEN(dev_priv) >= 6) {
 		fw_domains = __gen6_reg_read_fw_domains(uncore, offset);
 	} else {
-		WARN_ON(!IS_GEN_RANGE(dev_priv, 2, 5));
+		/* on devices with FW we expect to hit one of the above cases */
+		if (unlikely(uncore->flags & UNCORE_HAS_FORCEWAKE))
+			MISSING_CASE(INTEL_GEN(dev_priv));
+
 		fw_domains = 0;
 	}
 
@@ -1938,7 +1946,10 @@ intel_uncore_forcewake_for_write(struct drm_i915_private *dev_priv,
 	} else if (IS_GEN_RANGE(dev_priv, 6, 7)) {
 		fw_domains = FORCEWAKE_RENDER;
 	} else {
-		WARN_ON(!IS_GEN_RANGE(dev_priv, 2, 5));
+		/* on devices with FW we expect to hit one of the above cases */
+		if (unlikely(uncore->flags & UNCORE_HAS_FORCEWAKE))
+			MISSING_CASE(INTEL_GEN(dev_priv));
+
 		fw_domains = 0;
 	}
 
@@ -1969,7 +1980,7 @@ intel_uncore_forcewake_for_reg(struct drm_i915_private *dev_priv,
 
 	WARN_ON(!op);
 
-	if (intel_vgpu_active(dev_priv))
+	if (!(dev_priv->uncore.flags & UNCORE_HAS_FORCEWAKE))
 		return 0;
 
 	if (op & FW_REG_READ)
diff --git a/drivers/gpu/drm/i915/intel_uncore.h b/drivers/gpu/drm/i915/intel_uncore.h
index f7670cbc41c9..4947542c6ea7 100644
--- a/drivers/gpu/drm/i915/intel_uncore.h
+++ b/drivers/gpu/drm/i915/intel_uncore.h
@@ -127,6 +127,9 @@ struct intel_uncore {
 	} user_forcewake;
 
 	int unclaimed_mmio_check;
+
+	u32 flags;
+#define UNCORE_HAS_FORCEWAKE		BIT(0)
 };
 
 /* Iterate over initialised fw domains */
-- 
2.20.1