drm/i915: dynamically allocate forcewake domains

We'd like to introduce a display uncore with no forcewake domains, so
let's avoid wasting memory and be ready to allocate only what we need.
Even without multiple uncore, we still don't need all the domains on all
gens.

v2: avoid hidden control flow, improve checks (Tvrtko), fix IVB special
case, add failure injection point

Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190620010021.20637-6-daniele.ceraolospurio@intel.com

1 files changed, 73 insertions, 28 deletions

diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c
index 00bf5e085a2c..2bd602a41bb7 100644
--- a/drivers/gpu/drm/i915/intel_uncore.c
+++ b/drivers/gpu/drm/i915/intel_uncore.c
@@ -344,7 +344,7 @@ intel_uncore_fw_release_timer(struct hrtimer *timer)
 {
 	struct intel_uncore_forcewake_domain *domain =
 	       container_of(timer, struct intel_uncore_forcewake_domain, timer);
-	struct intel_uncore *uncore = forcewake_domain_to_uncore(domain);
+	struct intel_uncore *uncore = domain->uncore;
 	unsigned long irqflags;
 
 	assert_rpm_device_not_suspended(uncore->rpm);
@@ -1293,23 +1293,27 @@ do { \
 	(uncore)->funcs.read_fw_domains = x##_reg_read_fw_domains; \
 } while (0)
 
-static void fw_domain_init(struct intel_uncore *uncore,
-			   enum forcewake_domain_id domain_id,
-			   i915_reg_t reg_set,
-			   i915_reg_t reg_ack)
+static int __fw_domain_init(struct intel_uncore *uncore,
+			    enum forcewake_domain_id domain_id,
+			    i915_reg_t reg_set,
+			    i915_reg_t reg_ack)
 {
 	struct intel_uncore_forcewake_domain *d;
 
-	if (WARN_ON(domain_id >= FW_DOMAIN_ID_COUNT))
-		return;
+	GEM_BUG_ON(domain_id >= FW_DOMAIN_ID_COUNT);
+	GEM_BUG_ON(uncore->fw_domain[domain_id]);
 
-	d = &uncore->fw_domain[domain_id];
+	if (i915_inject_load_failure())
+		return -ENOMEM;
 
-	WARN_ON(d->wake_count);
+	d = kzalloc(sizeof(*d), GFP_KERNEL);
+	if (!d)
+		return -ENOMEM;
 
 	WARN_ON(!i915_mmio_reg_valid(reg_set));
 	WARN_ON(!i915_mmio_reg_valid(reg_ack));
 
+	d->uncore = uncore;
 	d->wake_count = 0;
 	d->reg_set = uncore->regs + i915_mmio_reg_offset(reg_set);
 	d->reg_ack = uncore->regs + i915_mmio_reg_offset(reg_ack);
@@ -1326,7 +1330,6 @@ static void fw_domain_init(struct intel_uncore *uncore,
 	BUILD_BUG_ON(FORCEWAKE_MEDIA_VEBOX0 != (1 << FW_DOMAIN_ID_MEDIA_VEBOX0));
 	BUILD_BUG_ON(FORCEWAKE_MEDIA_VEBOX1 != (1 << FW_DOMAIN_ID_MEDIA_VEBOX1));
 
-
 	d->mask = BIT(domain_id);
 
 	hrtimer_init(&d->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
@@ -1335,6 +1338,10 @@ static void fw_domain_init(struct intel_uncore *uncore,
 	uncore->fw_domains |= BIT(domain_id);
 
 	fw_domain_reset(d);
+
+	uncore->fw_domain[domain_id] = d;
+
+	return 0;
 }
 
 static void fw_domain_fini(struct intel_uncore *uncore,
@@ -1342,29 +1349,41 @@ static void fw_domain_fini(struct intel_uncore *uncore,
 {
 	struct intel_uncore_forcewake_domain *d;
 
-	if (WARN_ON(domain_id >= FW_DOMAIN_ID_COUNT))
-		return;
+	GEM_BUG_ON(domain_id >= FW_DOMAIN_ID_COUNT);
 
-	d = &uncore->fw_domain[domain_id];
+	d = fetch_and_zero(&uncore->fw_domain[domain_id]);
+	if (!d)
+		return;
 
+	uncore->fw_domains &= ~BIT(domain_id);
 	WARN_ON(d->wake_count);
 	WARN_ON(hrtimer_cancel(&d->timer));
-	memset(d, 0, sizeof(*d));
+	kfree(d);
+}
 
-	uncore->fw_domains &= ~BIT(domain_id);
+static void intel_uncore_fw_domains_fini(struct intel_uncore *uncore)
+{
+	struct intel_uncore_forcewake_domain *d;
+	int tmp;
+
+	for_each_fw_domain(d, uncore, tmp)
+		fw_domain_fini(uncore, d->id);
 }
 
-static void intel_uncore_fw_domains_init(struct intel_uncore *uncore)
+static int intel_uncore_fw_domains_init(struct intel_uncore *uncore)
 {
 	struct drm_i915_private *i915 = uncore->i915;
+	int ret = 0;
 
 	GEM_BUG_ON(!intel_uncore_has_forcewake(uncore));
 
+#define fw_domain_init(uncore__, id__, set__, ack__) \
+	(ret ?: (ret = __fw_domain_init((uncore__), (id__), (set__), (ack__))))
+
 	if (INTEL_GEN(i915) >= 11) {
 		int i;
 
-		uncore->funcs.force_wake_get =
-			fw_domains_get_with_fallback;
+		uncore->funcs.force_wake_get = fw_domains_get_with_fallback;
 		uncore->funcs.force_wake_put = fw_domains_put;
 		fw_domain_init(uncore, FW_DOMAIN_ID_RENDER,
 			       FORCEWAKE_RENDER_GEN9,
@@ -1372,6 +1391,7 @@ static void intel_uncore_fw_domains_init(struct intel_uncore *uncore)
 		fw_domain_init(uncore, FW_DOMAIN_ID_BLITTER,
 			       FORCEWAKE_BLITTER_GEN9,
 			       FORCEWAKE_ACK_BLITTER_GEN9);
+
 		for (i = 0; i < I915_MAX_VCS; i++) {
 			if (!HAS_ENGINE(i915, _VCS(i)))
 				continue;
@@ -1389,8 +1409,7 @@ static void intel_uncore_fw_domains_init(struct intel_uncore *uncore)
 				       FORCEWAKE_ACK_MEDIA_VEBOX_GEN11(i));
 		}
 	} else if (IS_GEN_RANGE(i915, 9, 10)) {
-		uncore->funcs.force_wake_get =
-			fw_domains_get_with_fallback;
+		uncore->funcs.force_wake_get = fw_domains_get_with_fallback;
 		uncore->funcs.force_wake_put = fw_domains_put;
 		fw_domain_init(uncore, FW_DOMAIN_ID_RENDER,
 			       FORCEWAKE_RENDER_GEN9,
@@ -1439,8 +1458,10 @@ static void intel_uncore_fw_domains_init(struct intel_uncore *uncore)
 		__raw_uncore_write32(uncore, FORCEWAKE, 0);
 		__raw_posting_read(uncore, ECOBUS);
 
-		fw_domain_init(uncore, FW_DOMAIN_ID_RENDER,
-			       FORCEWAKE_MT, FORCEWAKE_MT_ACK);
+		ret = __fw_domain_init(uncore, FW_DOMAIN_ID_RENDER,
+				       FORCEWAKE_MT, FORCEWAKE_MT_ACK);
+		if (ret)
+			goto out;
 
 		spin_lock_irq(&uncore->lock);
 		fw_domains_get_with_thread_status(uncore, FORCEWAKE_RENDER);
@@ -1451,6 +1472,7 @@ static void intel_uncore_fw_domains_init(struct intel_uncore *uncore)
 		if (!(ecobus & FORCEWAKE_MT_ENABLE)) {
 			DRM_INFO("No MT forcewake available on Ivybridge, this can result in issues\n");
 			DRM_INFO("when using vblank-synced partial screen updates.\n");
+			fw_domain_fini(uncore, FW_DOMAIN_ID_RENDER);
 			fw_domain_init(uncore, FW_DOMAIN_ID_RENDER,
 				       FORCEWAKE, FORCEWAKE_ACK);
 		}
@@ -1462,8 +1484,16 @@ static void intel_uncore_fw_domains_init(struct intel_uncore *uncore)
 			       FORCEWAKE, FORCEWAKE_ACK);
 	}
 
+#undef fw_domain_init
+
 	/* All future platforms are expected to require complex power gating */
-	WARN_ON(uncore->fw_domains == 0);
+	WARN_ON(!ret && uncore->fw_domains == 0);
+
+out:
+	if (ret)
+		intel_uncore_fw_domains_fini(uncore);
+
+	return ret;
 }
 
 #define ASSIGN_FW_DOMAINS_TABLE(uncore, d) \
@@ -1564,13 +1594,17 @@ static void uncore_raw_init(struct intel_uncore *uncore)
 	}
 }
 
-static void uncore_forcewake_init(struct intel_uncore *uncore)
+static int uncore_forcewake_init(struct intel_uncore *uncore)
 {
 	struct drm_i915_private *i915 = uncore->i915;
+	int ret;
 
 	GEM_BUG_ON(!intel_uncore_has_forcewake(uncore));
 
-	intel_uncore_fw_domains_init(uncore);
+	ret = intel_uncore_fw_domains_init(uncore);
+	if (ret)
+		return ret;
+
 	forcewake_early_sanitize(uncore, 0);
 
 	if (IS_GEN_RANGE(i915, 6, 7)) {
@@ -1603,6 +1637,8 @@ static void uncore_forcewake_init(struct intel_uncore *uncore)
 
 	uncore->pmic_bus_access_nb.notifier_call = i915_pmic_bus_access_notifier;
 	iosf_mbi_register_pmic_bus_access_notifier(&uncore->pmic_bus_access_nb);
+
+	return 0;
 }
 
 int intel_uncore_init_mmio(struct intel_uncore *uncore)
@@ -1621,10 +1657,13 @@ int intel_uncore_init_mmio(struct intel_uncore *uncore)
 
 	uncore->unclaimed_mmio_check = 1;
 
-	if (!intel_uncore_has_forcewake(uncore))
+	if (!intel_uncore_has_forcewake(uncore)) {
 		uncore_raw_init(uncore);
-	else
-		uncore_forcewake_init(uncore);
+	} else {
+		ret = uncore_forcewake_init(uncore);
+		if (ret)
+			goto out_mmio_cleanup;
+	}
 
 	/* make sure fw funcs are set if and only if we have fw*/
 	GEM_BUG_ON(intel_uncore_has_forcewake(uncore) != !!uncore->funcs.force_wake_get);
@@ -1646,6 +1685,11 @@ int intel_uncore_init_mmio(struct intel_uncore *uncore)
 		DRM_DEBUG("unclaimed mmio detected on uncore init, clearing\n");
 
 	return 0;
+
+out_mmio_cleanup:
+	uncore_mmio_cleanup(uncore);
+
+	return ret;
 }
 
 /*
@@ -1691,6 +1735,7 @@ void intel_uncore_fini_mmio(struct intel_uncore *uncore)
 		iosf_mbi_unregister_pmic_bus_access_notifier_unlocked(
 			&uncore->pmic_bus_access_nb);
 		intel_uncore_forcewake_reset(uncore);
+		intel_uncore_fw_domains_fini(uncore);
 		iosf_mbi_punit_release();
 	}