drm/amd/display: Try RGB before YCbCr 4:4:4 in stream validationgrafted

amdgpu_dm_create_validate_stream_for_sink() walks encoding_order[] and
uses the first encoding that validates. YCbCr 4:4:4 is listed before
RGB, so an HDMI sink that advertises 4:4:4 gets YCbCr 4:4:4 whenever the
"color format" property is left at AUTO, even though RGB fits the same
link.

That contradicts the documented AUTO behaviour for HDMI in enum
drm_connector_color_format (RGB, falling back to YCbCr 4:2:0 only when
the bandwidth is not available or the mode is 4:2:0-only), which the
amdgpu implementation of the property also describes. It also leaves
the "Broadcast RGB" property without effect on such sinks, since the
quantization range it selects only applies to RGB output.

Try RGB first. The mask still holds every encoding the sink supports,
so a mode that cannot carry RGB falls back exactly as before.

For reference, v7.2 picked RGB here unless YCbCr 4:4:4 was forced
through debugfs, while earlier kernels picked YCbCr 4:4:4 for any HDMI
sink that advertised it.

Fixes: 0b0ff65d3ca1 ("drm/amd/display: Refactor stream validation")
Suggested-by: Adolfo Rodrigues <adolfotregosa@gmail.com>
Assisted-by: Claude Code:claude-fable-5-1
Signed-off-by: Adrian Betschart <adrian.betschart@cinemaone.ch>
Reviewed-by: Fangzhi Zuo <jerry.zuo@amd.com>
Tested-by: Adolfo Rodrigues <adolfotregosa@gmail.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 7de432bc753133764dc40d37f9388da56de251e7)

4 files changed, 561 insertions, 0 deletions

diff --git a/drivers/dca/Kconfig b/drivers/dca/Kconfig
new file mode 100644
index 000000000..fd3348131
--- /dev/null
+++ b/drivers/dca/Kconfig
@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# DCA server configuration
+#
+
+config DCA
+	tristate
+
diff --git a/drivers/dca/Makefile b/drivers/dca/Makefile
new file mode 100644
index 000000000..f3f0f02c7
--- /dev/null
+++ b/drivers/dca/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_DCA) += dca.o
+dca-objs := dca-core.o dca-sysfs.o
diff --git a/drivers/dca/dca-core.c b/drivers/dca/dca-core.c
new file mode 100644
index 000000000..583510850
--- /dev/null
+++ b/drivers/dca/dca-core.c
@@ -0,0 +1,456 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright(c) 2007 - 2009 Intel Corporation. All rights reserved.
+ */
+
+/*
+ * This driver supports an interface for DCA clients and providers to meet.
+ */
+
+#include <linux/kernel.h>
+#include <linux/notifier.h>
+#include <linux/device.h>
+#include <linux/dca.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+#define DCA_VERSION "1.12.1"
+
+MODULE_VERSION(DCA_VERSION);
+MODULE_DESCRIPTION("Intel Direct Cache Access (DCA) service module");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Intel Corporation");
+
+static DEFINE_RAW_SPINLOCK(dca_lock);
+
+static LIST_HEAD(dca_domains);
+
+static BLOCKING_NOTIFIER_HEAD(dca_provider_chain);
+
+static int dca_providers_blocked;
+
+static struct pci_bus *dca_pci_rc_from_dev(struct device *dev)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct pci_bus *bus = pdev->bus;
+
+	while (bus->parent)
+		bus = bus->parent;
+
+	return bus;
+}
+
+static struct dca_domain *dca_allocate_domain(struct pci_bus *rc)
+{
+	struct dca_domain *domain;
+
+	domain = kzalloc_obj(*domain, GFP_NOWAIT);
+	if (!domain)
+		return NULL;
+
+	INIT_LIST_HEAD(&domain->dca_providers);
+	domain->pci_rc = rc;
+
+	return domain;
+}
+
+static void dca_free_domain(struct dca_domain *domain)
+{
+	list_del(&domain->node);
+	kfree(domain);
+}
+
+static int dca_provider_ioat_ver_3_0(struct device *dev)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+
+	return ((pdev->vendor == PCI_VENDOR_ID_INTEL) &&
+		((pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG0) ||
+		(pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG1) ||
+		(pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG2) ||
+		(pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG3) ||
+		(pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG4) ||
+		(pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG5) ||
+		(pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG6) ||
+		(pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG7)));
+}
+
+static void unregister_dca_providers(void)
+{
+	struct dca_provider *dca, *_dca;
+	struct list_head unregistered_providers;
+	struct dca_domain *domain;
+	unsigned long flags;
+
+	blocking_notifier_call_chain(&dca_provider_chain,
+				     DCA_PROVIDER_REMOVE, NULL);
+
+	INIT_LIST_HEAD(&unregistered_providers);
+
+	raw_spin_lock_irqsave(&dca_lock, flags);
+
+	if (list_empty(&dca_domains)) {
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return;
+	}
+
+	/* at this point only one domain in the list is expected */
+	domain = list_first_entry(&dca_domains, struct dca_domain, node);
+
+	list_for_each_entry_safe(dca, _dca, &domain->dca_providers, node)
+		list_move(&dca->node, &unregistered_providers);
+
+	dca_free_domain(domain);
+
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
+
+	list_for_each_entry_safe(dca, _dca, &unregistered_providers, node) {
+		dca_sysfs_remove_provider(dca);
+		list_del(&dca->node);
+	}
+}
+
+static struct dca_domain *dca_find_domain(struct pci_bus *rc)
+{
+	struct dca_domain *domain;
+
+	list_for_each_entry(domain, &dca_domains, node)
+		if (domain->pci_rc == rc)
+			return domain;
+
+	return NULL;
+}
+
+static struct dca_domain *dca_get_domain(struct device *dev)
+{
+	struct pci_bus *rc;
+	struct dca_domain *domain;
+
+	rc = dca_pci_rc_from_dev(dev);
+	domain = dca_find_domain(rc);
+
+	if (!domain) {
+		if (dca_provider_ioat_ver_3_0(dev) && !list_empty(&dca_domains))
+			dca_providers_blocked = 1;
+	}
+
+	return domain;
+}
+
+static struct dca_provider *dca_find_provider_by_dev(struct device *dev)
+{
+	struct dca_provider *dca;
+	struct pci_bus *rc;
+	struct dca_domain *domain;
+
+	if (dev) {
+		rc = dca_pci_rc_from_dev(dev);
+		domain = dca_find_domain(rc);
+		if (!domain)
+			return NULL;
+	} else {
+		if (!list_empty(&dca_domains))
+			domain = list_first_entry(&dca_domains,
+						  struct dca_domain,
+						  node);
+		else
+			return NULL;
+	}
+
+	list_for_each_entry(dca, &domain->dca_providers, node)
+		if ((!dev) || (dca->ops->dev_managed(dca, dev)))
+			return dca;
+
+	return NULL;
+}
+
+/**
+ * dca_add_requester - add a dca client to the list
+ * @dev - the device that wants dca service
+ */
+int dca_add_requester(struct device *dev)
+{
+	struct dca_provider *dca;
+	int err, slot = -ENODEV;
+	unsigned long flags;
+	struct pci_bus *pci_rc;
+	struct dca_domain *domain;
+
+	if (!dev)
+		return -EFAULT;
+
+	raw_spin_lock_irqsave(&dca_lock, flags);
+
+	/* check if the requester has not been added already */
+	dca = dca_find_provider_by_dev(dev);
+	if (dca) {
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return -EEXIST;
+	}
+
+	pci_rc = dca_pci_rc_from_dev(dev);
+	domain = dca_find_domain(pci_rc);
+	if (!domain) {
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return -ENODEV;
+	}
+
+	list_for_each_entry(dca, &domain->dca_providers, node) {
+		slot = dca->ops->add_requester(dca, dev);
+		if (slot >= 0)
+			break;
+	}
+
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
+
+	if (slot < 0)
+		return slot;
+
+	err = dca_sysfs_add_req(dca, dev, slot);
+	if (err) {
+		raw_spin_lock_irqsave(&dca_lock, flags);
+		if (dca == dca_find_provider_by_dev(dev))
+			dca->ops->remove_requester(dca, dev);
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return err;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dca_add_requester);
+
+/**
+ * dca_remove_requester - remove a dca client from the list
+ * @dev - the device that wants dca service
+ */
+int dca_remove_requester(struct device *dev)
+{
+	struct dca_provider *dca;
+	int slot;
+	unsigned long flags;
+
+	if (!dev)
+		return -EFAULT;
+
+	raw_spin_lock_irqsave(&dca_lock, flags);
+	dca = dca_find_provider_by_dev(dev);
+	if (!dca) {
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return -ENODEV;
+	}
+	slot = dca->ops->remove_requester(dca, dev);
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
+
+	if (slot < 0)
+		return slot;
+
+	dca_sysfs_remove_req(dca, slot);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dca_remove_requester);
+
+/**
+ * dca_common_get_tag - return the dca tag (serves both new and old api)
+ * @dev - the device that wants dca service
+ * @cpu - the cpuid as returned by get_cpu()
+ */
+static u8 dca_common_get_tag(struct device *dev, int cpu)
+{
+	struct dca_provider *dca;
+	u8 tag;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&dca_lock, flags);
+
+	dca = dca_find_provider_by_dev(dev);
+	if (!dca) {
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return -ENODEV;
+	}
+	tag = dca->ops->get_tag(dca, dev, cpu);
+
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
+	return tag;
+}
+
+/**
+ * dca3_get_tag - return the dca tag to the requester device
+ *                for the given cpu (new api)
+ * @dev - the device that wants dca service
+ * @cpu - the cpuid as returned by get_cpu()
+ */
+u8 dca3_get_tag(struct device *dev, int cpu)
+{
+	if (!dev)
+		return -EFAULT;
+
+	return dca_common_get_tag(dev, cpu);
+}
+EXPORT_SYMBOL_GPL(dca3_get_tag);
+
+/**
+ * dca_get_tag - return the dca tag for the given cpu (old api)
+ * @cpu - the cpuid as returned by get_cpu()
+ */
+u8 dca_get_tag(int cpu)
+{
+	return dca_common_get_tag(NULL, cpu);
+}
+EXPORT_SYMBOL_GPL(dca_get_tag);
+
+/**
+ * alloc_dca_provider - get data struct for describing a dca provider
+ * @ops - pointer to struct of dca operation function pointers
+ * @priv_size - size of extra mem to be added for provider's needs
+ */
+struct dca_provider *alloc_dca_provider(const struct dca_ops *ops,
+					int priv_size)
+{
+	struct dca_provider *dca;
+	int alloc_size;
+
+	alloc_size = (sizeof(*dca) + priv_size);
+	dca = kzalloc(alloc_size, GFP_KERNEL);
+	if (!dca)
+		return NULL;
+	dca->ops = ops;
+
+	return dca;
+}
+EXPORT_SYMBOL_GPL(alloc_dca_provider);
+
+/**
+ * free_dca_provider - release the dca provider data struct
+ * @ops - pointer to struct of dca operation function pointers
+ * @priv_size - size of extra mem to be added for provider's needs
+ */
+void free_dca_provider(struct dca_provider *dca)
+{
+	kfree(dca);
+}
+EXPORT_SYMBOL_GPL(free_dca_provider);
+
+/**
+ * register_dca_provider - register a dca provider
+ * @dca - struct created by alloc_dca_provider()
+ * @dev - device providing dca services
+ */
+int register_dca_provider(struct dca_provider *dca, struct device *dev)
+{
+	int err;
+	unsigned long flags;
+	struct dca_domain *domain, *newdomain = NULL;
+
+	raw_spin_lock_irqsave(&dca_lock, flags);
+	if (dca_providers_blocked) {
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return -ENODEV;
+	}
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
+
+	err = dca_sysfs_add_provider(dca, dev);
+	if (err)
+		return err;
+
+	raw_spin_lock_irqsave(&dca_lock, flags);
+	domain = dca_get_domain(dev);
+	if (!domain) {
+		struct pci_bus *rc;
+
+		if (dca_providers_blocked) {
+			raw_spin_unlock_irqrestore(&dca_lock, flags);
+			dca_sysfs_remove_provider(dca);
+			unregister_dca_providers();
+			return -ENODEV;
+		}
+
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		rc = dca_pci_rc_from_dev(dev);
+		newdomain = dca_allocate_domain(rc);
+		if (!newdomain)
+			return -ENODEV;
+		raw_spin_lock_irqsave(&dca_lock, flags);
+		/* Recheck, we might have raced after dropping the lock */
+		domain = dca_get_domain(dev);
+		if (!domain) {
+			domain = newdomain;
+			newdomain = NULL;
+			list_add(&domain->node, &dca_domains);
+		}
+	}
+	list_add(&dca->node, &domain->dca_providers);
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
+
+	blocking_notifier_call_chain(&dca_provider_chain,
+				     DCA_PROVIDER_ADD, NULL);
+	kfree(newdomain);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(register_dca_provider);
+
+/**
+ * unregister_dca_provider - remove a dca provider
+ * @dca - struct created by alloc_dca_provider()
+ */
+void unregister_dca_provider(struct dca_provider *dca, struct device *dev)
+{
+	unsigned long flags;
+	struct pci_bus *pci_rc;
+	struct dca_domain *domain;
+
+	blocking_notifier_call_chain(&dca_provider_chain,
+				     DCA_PROVIDER_REMOVE, NULL);
+
+	raw_spin_lock_irqsave(&dca_lock, flags);
+
+	if (list_empty(&dca_domains)) {
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return;
+	}
+
+	list_del(&dca->node);
+
+	pci_rc = dca_pci_rc_from_dev(dev);
+	domain = dca_find_domain(pci_rc);
+	if (list_empty(&domain->dca_providers))
+		dca_free_domain(domain);
+
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
+
+	dca_sysfs_remove_provider(dca);
+}
+EXPORT_SYMBOL_GPL(unregister_dca_provider);
+
+/**
+ * dca_register_notify - register a client's notifier callback
+ */
+void dca_register_notify(struct notifier_block *nb)
+{
+	blocking_notifier_chain_register(&dca_provider_chain, nb);
+}
+EXPORT_SYMBOL_GPL(dca_register_notify);
+
+/**
+ * dca_unregister_notify - remove a client's notifier callback
+ */
+void dca_unregister_notify(struct notifier_block *nb)
+{
+	blocking_notifier_chain_unregister(&dca_provider_chain, nb);
+}
+EXPORT_SYMBOL_GPL(dca_unregister_notify);
+
+static int __init dca_init(void)
+{
+	pr_info("dca service started, version %s\n", DCA_VERSION);
+	return dca_sysfs_init();
+}
+
+static void __exit dca_exit(void)
+{
+	dca_sysfs_exit();
+}
+
+arch_initcall(dca_init);
+module_exit(dca_exit);
+
diff --git a/drivers/dca/dca-sysfs.c b/drivers/dca/dca-sysfs.c
new file mode 100644
index 000000000..b915c2b46
--- /dev/null
+++ b/drivers/dca/dca-sysfs.c
@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright(c) 2007 - 2009 Intel Corporation. All rights reserved.
+ */
+
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/device.h>
+#include <linux/idr.h>
+#include <linux/kdev_t.h>
+#include <linux/err.h>
+#include <linux/dca.h>
+#include <linux/gfp.h>
+#include <linux/export.h>
+
+static const struct class dca_class = {
+	.name = "dca",
+};
+static struct idr dca_idr;
+static spinlock_t dca_idr_lock;
+
+int dca_sysfs_add_req(struct dca_provider *dca, struct device *dev, int slot)
+{
+	struct device *cd;
+	static int req_count;
+
+	cd = device_create(&dca_class, dca->cd, MKDEV(0, slot + 1), NULL,
+			   "requester%d", req_count++);
+	return PTR_ERR_OR_ZERO(cd);
+}
+
+void dca_sysfs_remove_req(struct dca_provider *dca, int slot)
+{
+	device_destroy(&dca_class, MKDEV(0, slot + 1));
+}
+
+int dca_sysfs_add_provider(struct dca_provider *dca, struct device *dev)
+{
+	struct device *cd;
+	int ret;
+
+	idr_preload(GFP_KERNEL);
+	spin_lock(&dca_idr_lock);
+
+	ret = idr_alloc(&dca_idr, dca, 0, 0, GFP_NOWAIT);
+	if (ret >= 0)
+		dca->id = ret;
+
+	spin_unlock(&dca_idr_lock);
+	idr_preload_end();
+	if (ret < 0)
+		return ret;
+
+	cd = device_create(&dca_class, dev, MKDEV(0, 0), NULL, "dca%d", dca->id);
+	if (IS_ERR(cd)) {
+		spin_lock(&dca_idr_lock);
+		idr_remove(&dca_idr, dca->id);
+		spin_unlock(&dca_idr_lock);
+		return PTR_ERR(cd);
+	}
+	dca->cd = cd;
+	return 0;
+}
+
+void dca_sysfs_remove_provider(struct dca_provider *dca)
+{
+	device_unregister(dca->cd);
+	dca->cd = NULL;
+	spin_lock(&dca_idr_lock);
+	idr_remove(&dca_idr, dca->id);
+	spin_unlock(&dca_idr_lock);
+}
+
+int __init dca_sysfs_init(void)
+{
+	int err;
+
+	idr_init(&dca_idr);
+	spin_lock_init(&dca_idr_lock);
+
+	err = class_register(&dca_class);
+	if (err) {
+		idr_destroy(&dca_idr);
+		return err;
+	}
+	return 0;
+}
+
+void __exit dca_sysfs_exit(void)
+{
+	class_unregister(&dca_class);
+	idr_destroy(&dca_idr);
+}
+