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, 135 insertions, 0 deletions

diff --git a/drivers/reset/reset-hsdk.c b/drivers/reset/reset-hsdk.c
new file mode 100644
index 000000000..98460e087
--- /dev/null
+++ b/drivers/reset/reset-hsdk.c
@@ -0,0 +1,135 @@
+/*
+ * Copyright (C) 2017 Synopsys.
+ *
+ * Synopsys HSDK Development platform reset driver.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#define to_hsdk_rst(p)	container_of((p), struct hsdk_rst, rcdev)
+
+struct hsdk_rst {
+	void __iomem			*regs_ctl;
+	void __iomem			*regs_rst;
+	spinlock_t			lock;
+	struct reset_controller_dev	rcdev;
+};
+
+static const u32 rst_map[] = {
+	BIT(16), /* APB_RST  */
+	BIT(17), /* AXI_RST  */
+	BIT(18), /* ETH_RST  */
+	BIT(19), /* USB_RST  */
+	BIT(20), /* SDIO_RST */
+	BIT(21), /* HDMI_RST */
+	BIT(22), /* GFX_RST  */
+	BIT(25), /* DMAC_RST */
+	BIT(31), /* EBI_RST  */
+};
+
+#define HSDK_MAX_RESETS			ARRAY_SIZE(rst_map)
+
+#define CGU_SYS_RST_CTRL		0x0
+#define CGU_IP_SW_RESET			0x0
+#define CGU_IP_SW_RESET_DELAY_SHIFT	16
+#define CGU_IP_SW_RESET_DELAY_MASK	GENMASK(31, CGU_IP_SW_RESET_DELAY_SHIFT)
+#define CGU_IP_SW_RESET_DELAY		0
+#define CGU_IP_SW_RESET_RESET		BIT(0)
+#define SW_RESET_TIMEOUT		10000
+
+static void hsdk_reset_config(struct hsdk_rst *rst, unsigned long id)
+{
+	writel(rst_map[id], rst->regs_ctl + CGU_SYS_RST_CTRL);
+}
+
+static int hsdk_reset_do(struct hsdk_rst *rst)
+{
+	u32 reg;
+
+	reg = readl(rst->regs_rst + CGU_IP_SW_RESET);
+	reg &= ~CGU_IP_SW_RESET_DELAY_MASK;
+	reg |= CGU_IP_SW_RESET_DELAY << CGU_IP_SW_RESET_DELAY_SHIFT;
+	reg |= CGU_IP_SW_RESET_RESET;
+	writel(reg, rst->regs_rst + CGU_IP_SW_RESET);
+
+	/* wait till reset bit is back to 0 */
+	return readl_poll_timeout_atomic(rst->regs_rst + CGU_IP_SW_RESET, reg,
+		!(reg & CGU_IP_SW_RESET_RESET), 5, SW_RESET_TIMEOUT);
+}
+
+static int hsdk_reset_reset(struct reset_controller_dev *rcdev,
+			      unsigned long id)
+{
+	struct hsdk_rst *rst = to_hsdk_rst(rcdev);
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&rst->lock, flags);
+	hsdk_reset_config(rst, id);
+	ret = hsdk_reset_do(rst);
+	spin_unlock_irqrestore(&rst->lock, flags);
+
+	return ret;
+}
+
+static const struct reset_control_ops hsdk_reset_ops = {
+	.reset	= hsdk_reset_reset,
+	.deassert = hsdk_reset_reset,
+};
+
+static int hsdk_reset_probe(struct platform_device *pdev)
+{
+	struct hsdk_rst *rst;
+
+	rst = devm_kzalloc(&pdev->dev, sizeof(*rst), GFP_KERNEL);
+	if (!rst)
+		return -ENOMEM;
+
+	rst->regs_ctl = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(rst->regs_ctl))
+		return PTR_ERR(rst->regs_ctl);
+
+	rst->regs_rst = devm_platform_ioremap_resource(pdev, 1);
+	if (IS_ERR(rst->regs_rst))
+		return PTR_ERR(rst->regs_rst);
+
+	spin_lock_init(&rst->lock);
+
+	rst->rcdev.owner = THIS_MODULE;
+	rst->rcdev.ops = &hsdk_reset_ops;
+	rst->rcdev.of_node = pdev->dev.of_node;
+	rst->rcdev.nr_resets = HSDK_MAX_RESETS;
+	rst->rcdev.of_reset_n_cells = 1;
+
+	return reset_controller_register(&rst->rcdev);
+}
+
+static const struct of_device_id hsdk_reset_dt_match[] = {
+	{ .compatible = "snps,hsdk-reset" },
+	{ },
+};
+
+static struct platform_driver hsdk_reset_driver = {
+	.probe	= hsdk_reset_probe,
+	.driver	= {
+		.name = "hsdk-reset",
+		.of_match_table = hsdk_reset_dt_match,
+	},
+};
+builtin_platform_driver(hsdk_reset_driver);
+
+MODULE_AUTHOR("Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>");
+MODULE_DESCRIPTION("Synopsys HSDK SDP reset driver");
+MODULE_LICENSE("GPL v2");