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, 259 insertions, 0 deletions

diff --git a/drivers/usb/misc/emi26.c b/drivers/usb/misc/emi26.c
new file mode 100644
index 000000000..24d841850
--- /dev/null
+++ b/drivers/usb/misc/emi26.c
@@ -0,0 +1,259 @@
+// SPDX-License-Identifier: GPL-2.0
+/* 
+ * Emagic EMI 2|6 usb audio interface firmware loader.
+ * Copyright (C) 2002
+ * 	Tapio Laxström (tapio.laxstrom@iptime.fi)
+ *
+ * emi26.c,v 1.13 2002/03/08 13:10:26 tapio Exp
+ */
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/ihex.h>
+
+#define EMI26_VENDOR_ID 		0x086a  /* Emagic Soft-und Hardware GmBH */
+#define EMI26_PRODUCT_ID		0x0100	/* EMI 2|6 without firmware */
+#define EMI26B_PRODUCT_ID		0x0102	/* EMI 2|6 without firmware */
+
+#define ANCHOR_LOAD_INTERNAL	0xA0	/* Vendor specific request code for Anchor Upload/Download (This one is implemented in the core) */
+#define ANCHOR_LOAD_EXTERNAL	0xA3	/* This command is not implemented in the core. Requires firmware */
+#define ANCHOR_LOAD_FPGA	0xA5	/* This command is not implemented in the core. Requires firmware. Emagic extension */
+#define MAX_INTERNAL_ADDRESS	0x1B3F	/* This is the highest internal RAM address for the AN2131Q */
+#define CPUCS_REG		0x7F92  /* EZ-USB Control and Status Register.  Bit 0 controls 8051 reset */ 
+#define INTERNAL_RAM(address)   (address <= MAX_INTERNAL_ADDRESS)
+
+static int emi26_writememory( struct usb_device *dev, int address,
+			      const unsigned char *data, int length,
+			      __u8 bRequest);
+static int emi26_set_reset(struct usb_device *dev, unsigned char reset_bit);
+static int emi26_load_firmware (struct usb_device *dev);
+static int emi26_probe(struct usb_interface *intf, const struct usb_device_id *id);
+static void emi26_disconnect(struct usb_interface *intf);
+
+/* thanks to drivers/usb/serial/keyspan_pda.c code */
+static int emi26_writememory (struct usb_device *dev, int address,
+			      const unsigned char *data, int length,
+			      __u8 request)
+{
+	int result;
+	unsigned char *buffer =  kmemdup(data, length, GFP_KERNEL);
+
+	if (!buffer) {
+		dev_err(&dev->dev, "kmalloc(%d) failed.\n", length);
+		return -ENOMEM;
+	}
+	/* Note: usb_control_msg returns negative value on error or length of the
+	 * 		 data that was written! */
+	result = usb_control_msg (dev, usb_sndctrlpipe(dev, 0), request, 0x40, address, 0, buffer, length, 300);
+	kfree (buffer);
+	return result;
+}
+
+/* thanks to drivers/usb/serial/keyspan_pda.c code */
+static int emi26_set_reset (struct usb_device *dev, unsigned char reset_bit)
+{
+	int response;
+	dev_info(&dev->dev, "%s - %d\n", __func__, reset_bit);
+	/* printk(KERN_DEBUG "%s - %d", __func__, reset_bit); */
+	response = emi26_writememory (dev, CPUCS_REG, &reset_bit, 1, 0xa0);
+	if (response < 0) {
+		dev_err(&dev->dev, "set_reset (%d) failed\n", reset_bit);
+	}
+	return response;
+}
+
+#define FW_LOAD_SIZE		1023
+
+static int emi26_load_firmware (struct usb_device *dev)
+{
+	const struct firmware *loader_fw = NULL;
+	const struct firmware *bitstream_fw = NULL;
+	const struct firmware *firmware_fw = NULL;
+	const struct ihex_binrec *rec;
+	int err = -ENOMEM;
+	int i;
+	__u32 addr;	/* Address to write */
+	__u8 *buf;
+
+	buf = kmalloc(FW_LOAD_SIZE, GFP_KERNEL);
+	if (!buf)
+		goto wraperr;
+
+	err = request_ihex_firmware(&loader_fw, "emi26/loader.fw", &dev->dev);
+	if (err)
+		goto nofw;
+
+	err = request_ihex_firmware(&bitstream_fw, "emi26/bitstream.fw",
+				    &dev->dev);
+	if (err)
+		goto nofw;
+
+	err = request_ihex_firmware(&firmware_fw, "emi26/firmware.fw",
+				    &dev->dev);
+	if (err) {
+	nofw:
+		dev_err(&dev->dev, "%s - request_firmware() failed\n",
+			__func__);
+		goto wraperr;
+	}
+
+	/* Assert reset (stop the CPU in the EMI) */
+	err = emi26_set_reset(dev,1);
+	if (err < 0)
+		goto wraperr;
+
+	rec = (const struct ihex_binrec *)loader_fw->data;
+	/* 1. We need to put the loader for the FPGA into the EZ-USB */
+	while (rec) {
+		err = emi26_writememory(dev, be32_to_cpu(rec->addr),
+					rec->data, be16_to_cpu(rec->len),
+					ANCHOR_LOAD_INTERNAL);
+		if (err < 0)
+			goto wraperr;
+		rec = ihex_next_binrec(rec);
+	}
+
+	/* De-assert reset (let the CPU run) */
+	err = emi26_set_reset(dev,0);
+	if (err < 0)
+		goto wraperr;
+	msleep(250);	/* let device settle */
+
+	/* 2. We upload the FPGA firmware into the EMI
+	 * Note: collect up to 1023 (yes!) bytes and send them with
+	 * a single request. This is _much_ faster! */
+	rec = (const struct ihex_binrec *)bitstream_fw->data;
+	do {
+		i = 0;
+		addr = be32_to_cpu(rec->addr);
+
+		/* intel hex records are terminated with type 0 element */
+		while (rec && (i + be16_to_cpu(rec->len) < FW_LOAD_SIZE)) {
+			memcpy(buf + i, rec->data, be16_to_cpu(rec->len));
+			i += be16_to_cpu(rec->len);
+			rec = ihex_next_binrec(rec);
+		}
+		err = emi26_writememory(dev, addr, buf, i, ANCHOR_LOAD_FPGA);
+		if (err < 0)
+			goto wraperr;
+	} while (rec);
+
+	/* Assert reset (stop the CPU in the EMI) */
+	err = emi26_set_reset(dev,1);
+	if (err < 0)
+		goto wraperr;
+
+	/* 3. We need to put the loader for the firmware into the EZ-USB (again...) */
+	for (rec = (const struct ihex_binrec *)loader_fw->data;
+	     rec; rec = ihex_next_binrec(rec)) {
+		err = emi26_writememory(dev, be32_to_cpu(rec->addr),
+					rec->data, be16_to_cpu(rec->len),
+					ANCHOR_LOAD_INTERNAL);
+		if (err < 0)
+			goto wraperr;
+	}
+	msleep(250);	/* let device settle */
+
+	/* De-assert reset (let the CPU run) */
+	err = emi26_set_reset(dev,0);
+	if (err < 0)
+		goto wraperr;
+
+	/* 4. We put the part of the firmware that lies in the external RAM into the EZ-USB */
+
+	for (rec = (const struct ihex_binrec *)firmware_fw->data;
+	     rec; rec = ihex_next_binrec(rec)) {
+		if (!INTERNAL_RAM(be32_to_cpu(rec->addr))) {
+			err = emi26_writememory(dev, be32_to_cpu(rec->addr),
+						rec->data, be16_to_cpu(rec->len),
+						ANCHOR_LOAD_EXTERNAL);
+			if (err < 0)
+				goto wraperr;
+		}
+	}
+
+	/* Assert reset (stop the CPU in the EMI) */
+	err = emi26_set_reset(dev,1);
+	if (err < 0)
+		goto wraperr;
+
+	for (rec = (const struct ihex_binrec *)firmware_fw->data;
+	     rec; rec = ihex_next_binrec(rec)) {
+		if (INTERNAL_RAM(be32_to_cpu(rec->addr))) {
+			err = emi26_writememory(dev, be32_to_cpu(rec->addr),
+						rec->data, be16_to_cpu(rec->len),
+						ANCHOR_LOAD_INTERNAL);
+			if (err < 0)
+				goto wraperr;
+		}
+	}
+
+	/* De-assert reset (let the CPU run) */
+	err = emi26_set_reset(dev,0);
+	if (err < 0)
+		goto wraperr;
+	msleep(250);	/* let device settle */
+
+	/* return 1 to fail the driver inialization
+	 * and give real driver change to load */
+	err = 1;
+
+wraperr:
+	if (err < 0)
+		dev_err(&dev->dev,"%s - error loading firmware: error = %d\n",
+			__func__, err);
+
+	release_firmware(loader_fw);
+	release_firmware(bitstream_fw);
+	release_firmware(firmware_fw);
+
+	kfree(buf);
+	return err;
+}
+
+static const struct usb_device_id id_table[] = {
+	{ USB_DEVICE(EMI26_VENDOR_ID, EMI26_PRODUCT_ID) },
+	{ USB_DEVICE(EMI26_VENDOR_ID, EMI26B_PRODUCT_ID) },
+	{ }                                             /* Terminating entry */
+};
+
+MODULE_DEVICE_TABLE (usb, id_table);
+
+static int emi26_probe(struct usb_interface *intf, const struct usb_device_id *id)
+{
+	struct usb_device *dev = interface_to_usbdev(intf);
+
+	dev_info(&intf->dev, "%s start\n", __func__);
+
+	emi26_load_firmware(dev);
+
+	/* do not return the driver context, let real audio driver do that */
+	return -EIO;
+}
+
+static void emi26_disconnect(struct usb_interface *intf)
+{
+}
+
+static struct usb_driver emi26_driver = {
+	.name		= "emi26 - firmware loader",
+	.probe		= emi26_probe,
+	.disconnect	= emi26_disconnect,
+	.id_table	= id_table,
+};
+
+module_usb_driver(emi26_driver);
+
+MODULE_AUTHOR("Tapio Laxström");
+MODULE_DESCRIPTION("Emagic EMI 2|6 firmware loader.");
+MODULE_LICENSE("GPL");
+
+MODULE_FIRMWARE("emi26/loader.fw");
+MODULE_FIRMWARE("emi26/bitstream.fw");
+MODULE_FIRMWARE("emi26/firmware.fw");
+/* vi:ai:syntax=c:sw=8:ts=8:tw=80
+ */