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)

1 files changed, 256 insertions, 0 deletions

diff --git a/drivers/reset/reset-intel-gw.c b/drivers/reset/reset-intel-gw.c
new file mode 100644
index 000000000..0db64cc8a
--- /dev/null
+++ b/drivers/reset/reset-intel-gw.c
@@ -0,0 +1,256 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 Intel Corporation.
+ * Lei Chuanhua <Chuanhua.lei@intel.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reboot.h>
+#include <linux/regmap.h>
+#include <linux/reset-controller.h>
+
+#define RCU_RST_STAT	0x0024
+#define RCU_RST_REQ	0x0048
+
+#define REG_OFFSET_MASK	GENMASK(31, 16)
+#define BIT_OFFSET_MASK	GENMASK(15, 8)
+#define STAT_BIT_OFFSET_MASK	GENMASK(7, 0)
+
+#define to_reset_data(x)	container_of(x, struct intel_reset_data, rcdev)
+
+struct intel_reset_soc {
+	bool legacy;
+	u32 reset_cell_count;
+};
+
+struct intel_reset_data {
+	struct reset_controller_dev rcdev;
+	const struct intel_reset_soc *soc_data;
+	struct regmap *regmap;
+	struct device *dev;
+	u32 reboot_id;
+};
+
+static const struct regmap_config intel_rcu_regmap_config = {
+	.name =		"intel-reset",
+	.reg_bits =	32,
+	.reg_stride =	4,
+	.val_bits =	32,
+};
+
+/*
+ * Reset status register offset relative to
+ * the reset control register(X) is X + 4
+ */
+static u32 id_to_reg_and_bit_offsets(struct intel_reset_data *data,
+				     unsigned long id, u32 *rst_req,
+				     u32 *req_bit, u32 *stat_bit)
+{
+	*rst_req = FIELD_GET(REG_OFFSET_MASK, id);
+	*req_bit = FIELD_GET(BIT_OFFSET_MASK, id);
+
+	if (data->soc_data->legacy)
+		*stat_bit = FIELD_GET(STAT_BIT_OFFSET_MASK, id);
+	else
+		*stat_bit = *req_bit;
+
+	if (data->soc_data->legacy && *rst_req == RCU_RST_REQ)
+		return RCU_RST_STAT;
+	else
+		return *rst_req + 0x4;
+}
+
+static int intel_set_clr_bits(struct intel_reset_data *data, unsigned long id,
+			      bool set)
+{
+	u32 rst_req, req_bit, rst_stat, stat_bit, val;
+	int ret;
+
+	rst_stat = id_to_reg_and_bit_offsets(data, id, &rst_req,
+					     &req_bit, &stat_bit);
+
+	val = set ? BIT(req_bit) : 0;
+	ret = regmap_update_bits(data->regmap, rst_req,  BIT(req_bit), val);
+	if (ret)
+		return ret;
+
+	return regmap_read_poll_timeout(data->regmap, rst_stat, val,
+					set == !!(val & BIT(stat_bit)), 20,
+					200);
+}
+
+static int intel_assert_device(struct reset_controller_dev *rcdev,
+			       unsigned long id)
+{
+	struct intel_reset_data *data = to_reset_data(rcdev);
+	int ret;
+
+	ret = intel_set_clr_bits(data, id, true);
+	if (ret)
+		dev_err(data->dev, "Reset assert failed %d\n", ret);
+
+	return ret;
+}
+
+static int intel_deassert_device(struct reset_controller_dev *rcdev,
+				 unsigned long id)
+{
+	struct intel_reset_data *data = to_reset_data(rcdev);
+	int ret;
+
+	ret = intel_set_clr_bits(data, id, false);
+	if (ret)
+		dev_err(data->dev, "Reset deassert failed %d\n", ret);
+
+	return ret;
+}
+
+static int intel_reset_status(struct reset_controller_dev *rcdev,
+			      unsigned long id)
+{
+	struct intel_reset_data *data = to_reset_data(rcdev);
+	u32 rst_req, req_bit, rst_stat, stat_bit, val;
+	int ret;
+
+	rst_stat = id_to_reg_and_bit_offsets(data, id, &rst_req,
+					     &req_bit, &stat_bit);
+	ret = regmap_read(data->regmap, rst_stat, &val);
+	if (ret)
+		return ret;
+
+	return !!(val & BIT(stat_bit));
+}
+
+static const struct reset_control_ops intel_reset_ops = {
+	.assert =	intel_assert_device,
+	.deassert =	intel_deassert_device,
+	.status	=	intel_reset_status,
+};
+
+static int intel_reset_xlate(struct reset_controller_dev *rcdev,
+			     const struct of_phandle_args *spec)
+{
+	struct intel_reset_data *data = to_reset_data(rcdev);
+	u32 id;
+
+	if (spec->args[1] > 31)
+		return -EINVAL;
+
+	id = FIELD_PREP(REG_OFFSET_MASK, spec->args[0]);
+	id |= FIELD_PREP(BIT_OFFSET_MASK, spec->args[1]);
+
+	if (data->soc_data->legacy) {
+		if (spec->args[2] > 31)
+			return -EINVAL;
+
+		id |= FIELD_PREP(STAT_BIT_OFFSET_MASK, spec->args[2]);
+	}
+
+	return id;
+}
+
+static int intel_reset_restart_handler(struct sys_off_data *data)
+{
+	struct intel_reset_data *reset_data = data->cb_data;
+
+	intel_assert_device(&reset_data->rcdev, reset_data->reboot_id);
+
+	return NOTIFY_DONE;
+}
+
+static int intel_reset_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct device *dev = &pdev->dev;
+	struct intel_reset_data *data;
+	void __iomem *base;
+	u32 rb_id[3];
+	int ret;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->soc_data = of_device_get_match_data(dev);
+	if (!data->soc_data)
+		return -ENODEV;
+
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	data->regmap = devm_regmap_init_mmio(dev, base,
+					     &intel_rcu_regmap_config);
+	if (IS_ERR(data->regmap)) {
+		dev_err(dev, "regmap initialization failed\n");
+		return PTR_ERR(data->regmap);
+	}
+
+	ret = device_property_read_u32_array(dev, "intel,global-reset", rb_id,
+					     data->soc_data->reset_cell_count);
+	if (ret) {
+		dev_err(dev, "Failed to get global reset offset!\n");
+		return ret;
+	}
+
+	data->dev =			dev;
+	data->rcdev.of_node =		np;
+	data->rcdev.owner =		dev->driver->owner;
+	data->rcdev.ops	=		&intel_reset_ops;
+	data->rcdev.of_xlate =		intel_reset_xlate;
+	data->rcdev.of_reset_n_cells =	data->soc_data->reset_cell_count;
+	ret = devm_reset_controller_register(&pdev->dev, &data->rcdev);
+	if (ret)
+		return ret;
+
+	data->reboot_id = FIELD_PREP(REG_OFFSET_MASK, rb_id[0]);
+	data->reboot_id |= FIELD_PREP(BIT_OFFSET_MASK, rb_id[1]);
+
+	if (data->soc_data->legacy)
+		data->reboot_id |= FIELD_PREP(STAT_BIT_OFFSET_MASK, rb_id[2]);
+
+	devm_register_restart_handler(&pdev->dev, intel_reset_restart_handler, data);
+
+	return 0;
+}
+
+static const struct intel_reset_soc xrx200_data = {
+	.legacy =		true,
+	.reset_cell_count =	3,
+};
+
+static const struct intel_reset_soc lgm_data = {
+	.legacy =		false,
+	.reset_cell_count =	2,
+};
+
+static const struct of_device_id intel_reset_match[] = {
+	{ .compatible = "intel,rcu-lgm", .data = &lgm_data },
+	{ .compatible = "intel,rcu-xrx200", .data = &xrx200_data },
+	{}
+};
+
+static struct platform_driver intel_reset_driver = {
+	.probe = intel_reset_probe,
+	.driver = {
+		.name = "intel-reset",
+		.of_match_table = intel_reset_match,
+	},
+};
+
+static int __init intel_reset_init(void)
+{
+	return platform_driver_register(&intel_reset_driver);
+}
+
+/*
+ * RCU is system core entity which is in Always On Domain whose clocks
+ * or resource initialization happens in system core initialization.
+ * Also, it is required for most of the platform or architecture
+ * specific devices to perform reset operation as part of initialization.
+ * So perform RCU as post core initialization.
+ */
+postcore_initcall(intel_reset_init);