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, 228 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-msm6242.c b/drivers/rtc/rtc-msm6242.c
new file mode 100644
index 000000000..80e364baa
--- /dev/null
+++ b/drivers/rtc/rtc-msm6242.c
@@ -0,0 +1,228 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  Oki MSM6242 RTC Driver
+ *
+ *  Copyright 2009 Geert Uytterhoeven
+ *
+ *  Based on the A2000 TOD code in arch/m68k/amiga/config.c
+ *  Copyright (C) 1993 Hamish Macdonald
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <linux/slab.h>
+
+
+enum {
+	MSM6242_SECOND1		= 0x0,	/* 1-second digit register */
+	MSM6242_SECOND10	= 0x1,	/* 10-second digit register */
+	MSM6242_MINUTE1		= 0x2,	/* 1-minute digit register */
+	MSM6242_MINUTE10	= 0x3,	/* 10-minute digit register */
+	MSM6242_HOUR1		= 0x4,	/* 1-hour digit register */
+	MSM6242_HOUR10		= 0x5,	/* PM/AM, 10-hour digit register */
+	MSM6242_DAY1		= 0x6,	/* 1-day digit register */
+	MSM6242_DAY10		= 0x7,	/* 10-day digit register */
+	MSM6242_MONTH1		= 0x8,	/* 1-month digit register */
+	MSM6242_MONTH10		= 0x9,	/* 10-month digit register */
+	MSM6242_YEAR1		= 0xa,	/* 1-year digit register */
+	MSM6242_YEAR10		= 0xb,	/* 10-year digit register */
+	MSM6242_WEEK		= 0xc,	/* Week register */
+	MSM6242_CD		= 0xd,	/* Control Register D */
+	MSM6242_CE		= 0xe,	/* Control Register E */
+	MSM6242_CF		= 0xf,	/* Control Register F */
+};
+
+#define MSM6242_HOUR10_AM	(0 << 2)
+#define MSM6242_HOUR10_PM	(1 << 2)
+#define MSM6242_HOUR10_HR_MASK	(3 << 0)
+
+#define MSM6242_WEEK_SUNDAY	0
+#define MSM6242_WEEK_MONDAY	1
+#define MSM6242_WEEK_TUESDAY	2
+#define MSM6242_WEEK_WEDNESDAY	3
+#define MSM6242_WEEK_THURSDAY	4
+#define MSM6242_WEEK_FRIDAY	5
+#define MSM6242_WEEK_SATURDAY	6
+
+#define MSM6242_CD_30_S_ADJ	(1 << 3)	/* 30-second adjustment */
+#define MSM6242_CD_IRQ_FLAG	(1 << 2)
+#define MSM6242_CD_BUSY		(1 << 1)
+#define MSM6242_CD_HOLD		(1 << 0)
+
+#define MSM6242_CE_T_MASK	(3 << 2)
+#define MSM6242_CE_T_64HZ	(0 << 2)	/* period 1/64 second */
+#define MSM6242_CE_T_1HZ	(1 << 2)	/* period 1 second */
+#define MSM6242_CE_T_1MINUTE	(2 << 2)	/* period 1 minute */
+#define MSM6242_CE_T_1HOUR	(3 << 2)	/* period 1 hour */
+
+#define MSM6242_CE_ITRPT_STND	(1 << 1)
+#define MSM6242_CE_MASK		(1 << 0)	/* STD.P output control */
+
+#define MSM6242_CF_TEST		(1 << 3)
+#define MSM6242_CF_12H		(0 << 2)
+#define MSM6242_CF_24H		(1 << 2)
+#define MSM6242_CF_STOP		(1 << 1)
+#define MSM6242_CF_REST		(1 << 0)	/* reset */
+
+
+struct msm6242_priv {
+	u32 __iomem *regs;
+	struct rtc_device *rtc;
+};
+
+static inline unsigned int msm6242_read(struct msm6242_priv *priv,
+				       unsigned int reg)
+{
+	return __raw_readl(&priv->regs[reg]) & 0xf;
+}
+
+static inline void msm6242_write(struct msm6242_priv *priv, unsigned int val,
+				unsigned int reg)
+{
+	__raw_writel(val, &priv->regs[reg]);
+}
+
+static void msm6242_lock(struct msm6242_priv *priv)
+{
+	int cnt = 5;
+
+	msm6242_write(priv, MSM6242_CD_HOLD|MSM6242_CD_IRQ_FLAG, MSM6242_CD);
+
+	while ((msm6242_read(priv, MSM6242_CD) & MSM6242_CD_BUSY) && cnt) {
+		msm6242_write(priv, MSM6242_CD_IRQ_FLAG, MSM6242_CD);
+		udelay(70);
+		msm6242_write(priv, MSM6242_CD_HOLD|MSM6242_CD_IRQ_FLAG, MSM6242_CD);
+		cnt--;
+	}
+
+	if (!cnt)
+		pr_warn("timed out waiting for RTC (0x%x)\n",
+			msm6242_read(priv, MSM6242_CD));
+}
+
+static void msm6242_unlock(struct msm6242_priv *priv)
+{
+	msm6242_write(priv, MSM6242_CD_IRQ_FLAG, MSM6242_CD);
+}
+
+static int msm6242_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct msm6242_priv *priv = dev_get_drvdata(dev);
+
+	msm6242_lock(priv);
+
+	tm->tm_sec  = msm6242_read(priv, MSM6242_SECOND10) * 10 +
+		      msm6242_read(priv, MSM6242_SECOND1);
+	tm->tm_min  = msm6242_read(priv, MSM6242_MINUTE10) * 10 +
+		      msm6242_read(priv, MSM6242_MINUTE1);
+	tm->tm_hour = (msm6242_read(priv, MSM6242_HOUR10) &
+		       MSM6242_HOUR10_HR_MASK) * 10 +
+		      msm6242_read(priv, MSM6242_HOUR1);
+	tm->tm_mday = msm6242_read(priv, MSM6242_DAY10) * 10 +
+		      msm6242_read(priv, MSM6242_DAY1);
+	tm->tm_wday = msm6242_read(priv, MSM6242_WEEK);
+	tm->tm_mon  = msm6242_read(priv, MSM6242_MONTH10) * 10 +
+		      msm6242_read(priv, MSM6242_MONTH1) - 1;
+	tm->tm_year = msm6242_read(priv, MSM6242_YEAR10) * 10 +
+		      msm6242_read(priv, MSM6242_YEAR1);
+	if (tm->tm_year <= 69)
+		tm->tm_year += 100;
+
+	if (!(msm6242_read(priv, MSM6242_CF) & MSM6242_CF_24H)) {
+		unsigned int pm = msm6242_read(priv, MSM6242_HOUR10) &
+				  MSM6242_HOUR10_PM;
+		if (!pm && tm->tm_hour == 12)
+			tm->tm_hour = 0;
+		else if (pm && tm->tm_hour != 12)
+			tm->tm_hour += 12;
+	}
+
+	msm6242_unlock(priv);
+
+	return 0;
+}
+
+static int msm6242_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct msm6242_priv *priv = dev_get_drvdata(dev);
+
+	msm6242_lock(priv);
+
+	msm6242_write(priv, tm->tm_sec / 10, MSM6242_SECOND10);
+	msm6242_write(priv, tm->tm_sec % 10, MSM6242_SECOND1);
+	msm6242_write(priv, tm->tm_min / 10, MSM6242_MINUTE10);
+	msm6242_write(priv, tm->tm_min % 10, MSM6242_MINUTE1);
+	if (msm6242_read(priv, MSM6242_CF) & MSM6242_CF_24H)
+		msm6242_write(priv, tm->tm_hour / 10, MSM6242_HOUR10);
+	else if (tm->tm_hour >= 12)
+		msm6242_write(priv, MSM6242_HOUR10_PM + (tm->tm_hour - 12) / 10,
+			      MSM6242_HOUR10);
+	else
+		msm6242_write(priv, tm->tm_hour / 10, MSM6242_HOUR10);
+	msm6242_write(priv, tm->tm_hour % 10, MSM6242_HOUR1);
+	msm6242_write(priv, tm->tm_mday / 10, MSM6242_DAY10);
+	msm6242_write(priv, tm->tm_mday % 10, MSM6242_DAY1);
+	if (tm->tm_wday != -1)
+		msm6242_write(priv, tm->tm_wday, MSM6242_WEEK);
+	msm6242_write(priv, (tm->tm_mon + 1) / 10, MSM6242_MONTH10);
+	msm6242_write(priv, (tm->tm_mon + 1) % 10, MSM6242_MONTH1);
+	if (tm->tm_year >= 100)
+		tm->tm_year -= 100;
+	msm6242_write(priv, tm->tm_year / 10, MSM6242_YEAR10);
+	msm6242_write(priv, tm->tm_year % 10, MSM6242_YEAR1);
+
+	msm6242_unlock(priv);
+	return 0;
+}
+
+static const struct rtc_class_ops msm6242_rtc_ops = {
+	.read_time	= msm6242_read_time,
+	.set_time	= msm6242_set_time,
+};
+
+static int __init msm6242_rtc_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct msm6242_priv *priv;
+	struct rtc_device *rtc;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->regs = devm_ioremap(&pdev->dev, res->start, resource_size(res));
+	if (!priv->regs)
+		return -ENOMEM;
+	platform_set_drvdata(pdev, priv);
+
+	rtc = devm_rtc_device_register(&pdev->dev, "rtc-msm6242",
+				&msm6242_rtc_ops, THIS_MODULE);
+	if (IS_ERR(rtc))
+		return PTR_ERR(rtc);
+
+	priv->rtc = rtc;
+	return 0;
+}
+
+static struct platform_driver msm6242_rtc_driver = {
+	.driver	= {
+		.name	= "rtc-msm6242",
+	},
+};
+
+module_platform_driver_probe(msm6242_rtc_driver, msm6242_rtc_probe);
+
+MODULE_AUTHOR("Geert Uytterhoeven <geert@linux-m68k.org>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Oki MSM6242 RTC driver");
+MODULE_ALIAS("platform:rtc-msm6242");