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, 150 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-meson-vrtc.c b/drivers/rtc/rtc-meson-vrtc.c
new file mode 100644
index 000000000..7d38258cb
--- /dev/null
+++ b/drivers/rtc/rtc-meson-vrtc.c
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 BayLibre, SAS
+ * Author: Neil Armstrong <narmstrong@baylibre.com>
+ * Copyright (C) 2015 Amlogic, Inc. All rights reserved.
+ */
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/time64.h>
+
+struct meson_vrtc_data {
+	void __iomem *io_alarm;
+	unsigned long alarm_time;
+	bool enabled;
+};
+
+static int meson_vrtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct timespec64 time;
+
+	dev_dbg(dev, "%s\n", __func__);
+	ktime_get_real_ts64(&time);
+	rtc_time64_to_tm(time.tv_sec, tm);
+
+	return 0;
+}
+
+static void meson_vrtc_set_wakeup_time(struct meson_vrtc_data *vrtc,
+				       unsigned long time)
+{
+	writel_relaxed(time, vrtc->io_alarm);
+}
+
+static int meson_vrtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+	struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);
+
+	dev_dbg(dev, "%s: alarm->enabled=%d\n", __func__, alarm->enabled);
+	if (alarm->enabled)
+		vrtc->alarm_time = rtc_tm_to_time64(&alarm->time);
+	else
+		vrtc->alarm_time = 0;
+
+	return 0;
+}
+
+static int meson_vrtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+	struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);
+
+	vrtc->enabled = enabled;
+	return 0;
+}
+
+static const struct rtc_class_ops meson_vrtc_ops = {
+	.read_time = meson_vrtc_read_time,
+	.set_alarm = meson_vrtc_set_alarm,
+	.alarm_irq_enable = meson_vrtc_alarm_irq_enable,
+};
+
+static int meson_vrtc_probe(struct platform_device *pdev)
+{
+	struct meson_vrtc_data *vrtc;
+	struct rtc_device *rtc;
+
+	vrtc = devm_kzalloc(&pdev->dev, sizeof(*vrtc), GFP_KERNEL);
+	if (!vrtc)
+		return -ENOMEM;
+
+	vrtc->io_alarm = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(vrtc->io_alarm))
+		return PTR_ERR(vrtc->io_alarm);
+
+	device_init_wakeup(&pdev->dev, true);
+
+	platform_set_drvdata(pdev, vrtc);
+
+	rtc = devm_rtc_allocate_device(&pdev->dev);
+	if (IS_ERR(rtc))
+		return PTR_ERR(rtc);
+
+	rtc->ops = &meson_vrtc_ops;
+	return devm_rtc_register_device(rtc);
+}
+
+static int __maybe_unused meson_vrtc_suspend(struct device *dev)
+{
+	struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);
+
+	dev_dbg(dev, "%s\n", __func__);
+	if (vrtc->alarm_time) {
+		unsigned long local_time;
+		long alarm_secs;
+		struct timespec64 time;
+
+		ktime_get_real_ts64(&time);
+		local_time = time.tv_sec;
+
+		dev_dbg(dev, "alarm_time = %lus, local_time=%lus\n",
+			vrtc->alarm_time, local_time);
+		alarm_secs = vrtc->alarm_time - local_time;
+		if (alarm_secs > 0) {
+			meson_vrtc_set_wakeup_time(vrtc, alarm_secs);
+			dev_dbg(dev, "system will wakeup in %lds.\n",
+				alarm_secs);
+		} else {
+			dev_err(dev, "alarm time already passed: %lds.\n",
+				alarm_secs);
+		}
+	}
+
+	return 0;
+}
+
+static int __maybe_unused meson_vrtc_resume(struct device *dev)
+{
+	struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);
+
+	dev_dbg(dev, "%s\n", __func__);
+
+	vrtc->alarm_time = 0;
+	meson_vrtc_set_wakeup_time(vrtc, 0);
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(meson_vrtc_pm_ops,
+			 meson_vrtc_suspend, meson_vrtc_resume);
+
+static const struct of_device_id meson_vrtc_dt_match[] = {
+	{ .compatible = "amlogic,meson-vrtc"},
+	{},
+};
+MODULE_DEVICE_TABLE(of, meson_vrtc_dt_match);
+
+static struct platform_driver meson_vrtc_driver = {
+	.probe = meson_vrtc_probe,
+	.driver = {
+		.name = "meson-vrtc",
+		.of_match_table = meson_vrtc_dt_match,
+		.pm = &meson_vrtc_pm_ops,
+	},
+};
+
+module_platform_driver(meson_vrtc_driver);
+
+MODULE_DESCRIPTION("Amlogic Virtual Wakeup RTC Timer driver");
+MODULE_LICENSE("GPL");