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, 297 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-mpfs.c b/drivers/rtc/rtc-mpfs.c
new file mode 100644
index 000000000..ece6de4a6
--- /dev/null
+++ b/drivers/rtc/rtc-mpfs.c
@@ -0,0 +1,297 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Microchip MPFS RTC driver
+ *
+ * Copyright (c) 2021-2022 Microchip Corporation. All rights reserved.
+ *
+ * Author: Daire McNamara <daire.mcnamara@microchip.com>
+ *         & Conor Dooley <conor.dooley@microchip.com>
+ */
+#include "linux/bits.h"
+#include "linux/iopoll.h"
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_wakeirq.h>
+#include <linux/slab.h>
+#include <linux/rtc.h>
+
+#define CONTROL_REG		0x00
+#define MODE_REG		0x04
+#define PRESCALER_REG		0x08
+#define ALARM_LOWER_REG		0x0c
+#define ALARM_UPPER_REG		0x10
+#define COMPARE_LOWER_REG	0x14
+#define COMPARE_UPPER_REG	0x18
+#define DATETIME_LOWER_REG	0x20
+#define DATETIME_UPPER_REG	0x24
+
+#define CONTROL_RUNNING_BIT	BIT(0)
+#define CONTROL_START_BIT	BIT(0)
+#define CONTROL_STOP_BIT	BIT(1)
+#define CONTROL_ALARM_ON_BIT	BIT(2)
+#define CONTROL_ALARM_OFF_BIT	BIT(3)
+#define CONTROL_RESET_BIT	BIT(4)
+#define CONTROL_UPLOAD_BIT	BIT(5)
+#define CONTROL_DOWNLOAD_BIT	BIT(6)
+#define CONTROL_MATCH_BIT	BIT(7)
+#define CONTROL_WAKEUP_CLR_BIT	BIT(8)
+#define CONTROL_WAKEUP_SET_BIT	BIT(9)
+#define CONTROL_UPDATED_BIT	BIT(10)
+
+#define MODE_CLOCK_CALENDAR	BIT(0)
+#define MODE_WAKE_EN		BIT(1)
+#define MODE_WAKE_RESET		BIT(2)
+#define MODE_WAKE_CONTINUE	BIT(3)
+
+#define MAX_PRESCALER_COUNT	GENMASK(25, 0)
+#define DATETIME_UPPER_MASK	GENMASK(29, 0)
+#define ALARM_UPPER_MASK	GENMASK(10, 0)
+
+#define UPLOAD_TIMEOUT_US	50
+
+struct mpfs_rtc_dev {
+	struct rtc_device *rtc;
+	void __iomem *base;
+};
+
+static void mpfs_rtc_start(struct mpfs_rtc_dev *rtcdev)
+{
+	u32 ctrl;
+
+	ctrl = readl(rtcdev->base + CONTROL_REG);
+	ctrl &= ~CONTROL_STOP_BIT;
+	ctrl |= CONTROL_START_BIT;
+	writel(ctrl, rtcdev->base + CONTROL_REG);
+}
+
+static void mpfs_rtc_clear_irq(struct mpfs_rtc_dev *rtcdev)
+{
+	u32 val = readl(rtcdev->base + CONTROL_REG);
+
+	val &= ~(CONTROL_ALARM_ON_BIT | CONTROL_STOP_BIT);
+	val |= CONTROL_ALARM_OFF_BIT;
+	writel(val, rtcdev->base + CONTROL_REG);
+	/*
+	 * Ensure that the posted write to the CONTROL_REG register completed before
+	 * returning from this function. Not doing this may result in the interrupt
+	 * only being cleared some time after this function returns.
+	 */
+	(void)readl(rtcdev->base + CONTROL_REG);
+}
+
+static int mpfs_rtc_readtime(struct device *dev, struct rtc_time *tm)
+{
+	struct mpfs_rtc_dev *rtcdev = dev_get_drvdata(dev);
+	u64 time;
+
+	time = readl(rtcdev->base + DATETIME_LOWER_REG);
+	time |= ((u64)readl(rtcdev->base + DATETIME_UPPER_REG) & DATETIME_UPPER_MASK) << 32;
+	rtc_time64_to_tm(time, tm);
+
+	return 0;
+}
+
+static int mpfs_rtc_settime(struct device *dev, struct rtc_time *tm)
+{
+	struct mpfs_rtc_dev *rtcdev = dev_get_drvdata(dev);
+	u32 ctrl, prog;
+	u64 time;
+	int ret;
+
+	time = rtc_tm_to_time64(tm);
+
+	writel((u32)time, rtcdev->base + DATETIME_LOWER_REG);
+	writel((u32)(time >> 32) & DATETIME_UPPER_MASK, rtcdev->base + DATETIME_UPPER_REG);
+
+	ctrl = readl(rtcdev->base + CONTROL_REG);
+	ctrl &= ~CONTROL_STOP_BIT;
+	ctrl |= CONTROL_UPLOAD_BIT;
+	writel(ctrl, rtcdev->base + CONTROL_REG);
+
+	ret = read_poll_timeout(readl, prog, !(prog & CONTROL_UPLOAD_BIT), 0, UPLOAD_TIMEOUT_US,
+				false, rtcdev->base + CONTROL_REG);
+	if (ret) {
+		dev_err(dev, "timed out uploading time to rtc");
+		return ret;
+	}
+	mpfs_rtc_start(rtcdev);
+
+	return 0;
+}
+
+static int mpfs_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct mpfs_rtc_dev *rtcdev = dev_get_drvdata(dev);
+	u32 mode = readl(rtcdev->base + MODE_REG);
+	u64 time;
+
+	alrm->enabled = mode & MODE_WAKE_EN;
+
+	time = (u64)readl(rtcdev->base + ALARM_LOWER_REG) << 32;
+	time |= (readl(rtcdev->base + ALARM_UPPER_REG) & ALARM_UPPER_MASK);
+	rtc_time64_to_tm(time, &alrm->time);
+
+	return 0;
+}
+
+static int mpfs_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct mpfs_rtc_dev *rtcdev = dev_get_drvdata(dev);
+	u32 mode, ctrl;
+	u64 time;
+
+	/* Disable the alarm before updating */
+	ctrl = readl(rtcdev->base + CONTROL_REG);
+	ctrl |= CONTROL_ALARM_OFF_BIT;
+	writel(ctrl, rtcdev->base + CONTROL_REG);
+
+	time = rtc_tm_to_time64(&alrm->time);
+
+	writel((u32)time, rtcdev->base + ALARM_LOWER_REG);
+	writel((u32)(time >> 32) & ALARM_UPPER_MASK, rtcdev->base + ALARM_UPPER_REG);
+
+	/* Bypass compare register in alarm mode */
+	writel(GENMASK(31, 0), rtcdev->base + COMPARE_LOWER_REG);
+	writel(GENMASK(29, 0), rtcdev->base + COMPARE_UPPER_REG);
+
+	/* Configure the RTC to enable the alarm. */
+	ctrl = readl(rtcdev->base + CONTROL_REG);
+	mode = readl(rtcdev->base + MODE_REG);
+	if (alrm->enabled) {
+		mode = MODE_WAKE_EN | MODE_WAKE_CONTINUE;
+		/* Enable the alarm */
+		ctrl &= ~CONTROL_ALARM_OFF_BIT;
+		ctrl |= CONTROL_ALARM_ON_BIT;
+	}
+	ctrl &= ~CONTROL_STOP_BIT;
+	ctrl |= CONTROL_START_BIT;
+	writel(ctrl, rtcdev->base + CONTROL_REG);
+	writel(mode, rtcdev->base + MODE_REG);
+
+	return 0;
+}
+
+static int mpfs_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+	struct mpfs_rtc_dev *rtcdev = dev_get_drvdata(dev);
+	u32 ctrl;
+
+	ctrl = readl(rtcdev->base + CONTROL_REG);
+	ctrl &= ~(CONTROL_ALARM_ON_BIT | CONTROL_ALARM_OFF_BIT | CONTROL_STOP_BIT);
+
+	if (enabled)
+		ctrl |= CONTROL_ALARM_ON_BIT;
+	else
+		ctrl |= CONTROL_ALARM_OFF_BIT;
+
+	writel(ctrl, rtcdev->base + CONTROL_REG);
+
+	return 0;
+}
+
+static irqreturn_t mpfs_rtc_wakeup_irq_handler(int irq, void *dev)
+{
+	struct mpfs_rtc_dev *rtcdev = dev;
+
+	mpfs_rtc_clear_irq(rtcdev);
+
+	rtc_update_irq(rtcdev->rtc, 1, RTC_IRQF | RTC_AF);
+
+	return IRQ_HANDLED;
+}
+
+static const struct rtc_class_ops mpfs_rtc_ops = {
+	.read_time		= mpfs_rtc_readtime,
+	.set_time		= mpfs_rtc_settime,
+	.read_alarm		= mpfs_rtc_readalarm,
+	.set_alarm		= mpfs_rtc_setalarm,
+	.alarm_irq_enable	= mpfs_rtc_alarm_irq_enable,
+};
+
+static int mpfs_rtc_probe(struct platform_device *pdev)
+{
+	struct mpfs_rtc_dev *rtcdev;
+	struct clk *clk;
+	unsigned long prescaler;
+	int wakeup_irq, ret;
+
+	rtcdev = devm_kzalloc(&pdev->dev, sizeof(struct mpfs_rtc_dev), GFP_KERNEL);
+	if (!rtcdev)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, rtcdev);
+
+	rtcdev->rtc = devm_rtc_allocate_device(&pdev->dev);
+	if (IS_ERR(rtcdev->rtc))
+		return PTR_ERR(rtcdev->rtc);
+
+	rtcdev->rtc->ops = &mpfs_rtc_ops;
+
+	/* range is capped by alarm max, lower reg is 31:0 & upper is 10:0 */
+	rtcdev->rtc->range_max = GENMASK_ULL(42, 0);
+
+	clk = devm_clk_get_enabled(&pdev->dev, "rtc");
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	rtcdev->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(rtcdev->base)) {
+		dev_dbg(&pdev->dev, "invalid ioremap resources\n");
+		return PTR_ERR(rtcdev->base);
+	}
+
+	wakeup_irq = platform_get_irq(pdev, 0);
+	if (wakeup_irq <= 0) {
+		dev_dbg(&pdev->dev, "could not get wakeup irq\n");
+		return wakeup_irq;
+	}
+	ret = devm_request_irq(&pdev->dev, wakeup_irq, mpfs_rtc_wakeup_irq_handler, 0,
+			       dev_name(&pdev->dev), rtcdev);
+	if (ret) {
+		dev_dbg(&pdev->dev, "could not request wakeup irq\n");
+		return ret;
+	}
+
+	/* prescaler hardware adds 1 to reg value */
+	prescaler = clk_get_rate(devm_clk_get(&pdev->dev, "rtcref")) - 1;
+	if (prescaler > MAX_PRESCALER_COUNT) {
+		dev_dbg(&pdev->dev, "invalid prescaler %lu\n", prescaler);
+		return -EINVAL;
+	}
+
+	writel(prescaler, rtcdev->base + PRESCALER_REG);
+	dev_info(&pdev->dev, "prescaler set to: %lu\n", prescaler);
+
+	devm_device_init_wakeup(&pdev->dev);
+	ret = devm_pm_set_wake_irq(&pdev->dev, wakeup_irq);
+	if (ret)
+		dev_err(&pdev->dev, "failed to enable irq wake\n");
+
+	return devm_rtc_register_device(rtcdev->rtc);
+}
+
+static const struct of_device_id mpfs_rtc_of_match[] = {
+	{ .compatible = "microchip,mpfs-rtc" },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, mpfs_rtc_of_match);
+
+static struct platform_driver mpfs_rtc_driver = {
+	.probe = mpfs_rtc_probe,
+	.driver	= {
+		.name = "mpfs_rtc",
+		.of_match_table = mpfs_rtc_of_match,
+	},
+};
+
+module_platform_driver(mpfs_rtc_driver);
+
+MODULE_DESCRIPTION("Real time clock for Microchip Polarfire SoC");
+MODULE_AUTHOR("Daire McNamara <daire.mcnamara@microchip.com>");
+MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
+MODULE_LICENSE("GPL");