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, 411 insertions, 0 deletions

diff --git a/drivers/block/z2ram.c b/drivers/block/z2ram.c
new file mode 100644
index 000000000..b216cba1c
--- /dev/null
+++ b/drivers/block/z2ram.c
@@ -0,0 +1,411 @@
+/*
+** z2ram - Amiga pseudo-driver to access 16bit-RAM in ZorroII space
+**         as a block device, to be used as a RAM disk or swap space
+** 
+** Copyright (C) 1994 by Ingo Wilken (Ingo.Wilken@informatik.uni-oldenburg.de)
+**
+** ++Geert: support for zorro_unused_z2ram, better range checking
+** ++roman: translate accesses via an array
+** ++Milan: support for ChipRAM usage
+** ++yambo: converted to 2.0 kernel
+** ++yambo: modularized and support added for 3 minor devices including:
+**          MAJOR  MINOR  DESCRIPTION
+**          -----  -----  ----------------------------------------------
+**          37     0       Use Zorro II and Chip ram
+**          37     1       Use only Zorro II ram
+**          37     2       Use only Chip ram
+**          37     4-7     Use memory list entry 1-4 (first is 0)
+** ++jskov: support for 1-4th memory list entry.
+**
+** Permission to use, copy, modify, and distribute this software and its
+** documentation for any purpose and without fee is hereby granted, provided
+** that the above copyright notice appear in all copies and that both that
+** copyright notice and this permission notice appear in supporting
+** documentation.  This software is provided "as is" without express or
+** implied warranty.
+*/
+
+#define DEVICE_NAME "Z2RAM"
+
+#include <linux/major.h>
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/blk-mq.h>
+#include <linux/bitops.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/pgtable.h>
+
+#include <asm/setup.h>
+#include <asm/amigahw.h>
+
+#include <linux/zorro.h>
+
+#define Z2MINOR_COMBINED      (0)
+#define Z2MINOR_Z2ONLY        (1)
+#define Z2MINOR_CHIPONLY      (2)
+#define Z2MINOR_MEMLIST1      (4)
+#define Z2MINOR_MEMLIST2      (5)
+#define Z2MINOR_MEMLIST3      (6)
+#define Z2MINOR_MEMLIST4      (7)
+#define Z2MINOR_COUNT         (8)	/* Move this down when adding a new minor */
+
+#define Z2RAM_CHUNK1024       ( Z2RAM_CHUNKSIZE >> 10 )
+
+static DEFINE_MUTEX(z2ram_mutex);
+static u_long *z2ram_map = NULL;
+static u_long z2ram_size = 0;
+static int z2_count = 0;
+static int chip_count = 0;
+static int list_count = 0;
+static int current_device = -1;
+
+static DEFINE_SPINLOCK(z2ram_lock);
+
+static struct gendisk *z2ram_gendisk[Z2MINOR_COUNT];
+
+static blk_status_t z2_queue_rq(struct blk_mq_hw_ctx *hctx,
+				const struct blk_mq_queue_data *bd)
+{
+	struct request *req = bd->rq;
+	unsigned long start = blk_rq_pos(req) << 9;
+	unsigned long len = blk_rq_cur_bytes(req);
+
+	blk_mq_start_request(req);
+
+	if (start + len > z2ram_size) {
+		pr_err(DEVICE_NAME ": bad access: block=%llu, "
+		       "count=%u\n",
+		       (unsigned long long)blk_rq_pos(req),
+		       blk_rq_cur_sectors(req));
+		return BLK_STS_IOERR;
+	}
+
+	spin_lock_irq(&z2ram_lock);
+
+	while (len) {
+		unsigned long addr = start & Z2RAM_CHUNKMASK;
+		unsigned long size = Z2RAM_CHUNKSIZE - addr;
+		void *buffer = bio_data(req->bio);
+
+		if (len < size)
+			size = len;
+		addr += z2ram_map[start >> Z2RAM_CHUNKSHIFT];
+		if (rq_data_dir(req) == READ)
+			memcpy(buffer, (char *)addr, size);
+		else
+			memcpy((char *)addr, buffer, size);
+		start += size;
+		len -= size;
+	}
+
+	spin_unlock_irq(&z2ram_lock);
+	blk_mq_end_request(req, BLK_STS_OK);
+	return BLK_STS_OK;
+}
+
+static void get_z2ram(void)
+{
+	int i;
+
+	for (i = 0; i < Z2RAM_SIZE / Z2RAM_CHUNKSIZE; i++) {
+		if (test_bit(i, zorro_unused_z2ram)) {
+			z2_count++;
+			z2ram_map[z2ram_size++] =
+			    (unsigned long)ZTWO_VADDR(Z2RAM_START) +
+			    (i << Z2RAM_CHUNKSHIFT);
+			clear_bit(i, zorro_unused_z2ram);
+		}
+	}
+
+	return;
+}
+
+static void get_chipram(void)
+{
+
+	while (amiga_chip_avail() > (Z2RAM_CHUNKSIZE * 4)) {
+		chip_count++;
+		z2ram_map[z2ram_size] =
+		    (u_long) amiga_chip_alloc(Z2RAM_CHUNKSIZE, "z2ram");
+
+		if (z2ram_map[z2ram_size] == 0) {
+			break;
+		}
+
+		z2ram_size++;
+	}
+
+	return;
+}
+
+static int z2_open(struct gendisk *disk, blk_mode_t mode)
+{
+	int device = disk->first_minor;
+	int max_z2_map = (Z2RAM_SIZE / Z2RAM_CHUNKSIZE) * sizeof(z2ram_map[0]);
+	int max_chip_map = (amiga_chip_size / Z2RAM_CHUNKSIZE) *
+	    sizeof(z2ram_map[0]);
+	int rc = -ENOMEM;
+
+	mutex_lock(&z2ram_mutex);
+	if (current_device != -1 && current_device != device) {
+		rc = -EBUSY;
+		goto err_out;
+	}
+
+	if (current_device == -1) {
+		z2_count = 0;
+		chip_count = 0;
+		list_count = 0;
+		z2ram_size = 0;
+
+		/* Use a specific list entry. */
+		if (device >= Z2MINOR_MEMLIST1 && device <= Z2MINOR_MEMLIST4) {
+			int index = device - Z2MINOR_MEMLIST1 + 1;
+			unsigned long size, paddr, vaddr;
+
+			if (index >= m68k_realnum_memory) {
+				printk(KERN_ERR DEVICE_NAME
+				       ": no such entry in z2ram_map\n");
+				goto err_out;
+			}
+
+			paddr = m68k_memory[index].addr;
+			size = m68k_memory[index].size & ~(Z2RAM_CHUNKSIZE - 1);
+
+#ifdef __powerpc__
+			/* FIXME: ioremap doesn't build correct memory tables. */
+			{
+				vfree(vmalloc(size));
+			}
+
+			vaddr = (unsigned long)ioremap_wt(paddr, size);
+
+#else
+			vaddr =
+			    (unsigned long)z_remap_nocache_nonser(paddr, size);
+#endif
+			z2ram_map =
+			    kmalloc_objs(z2ram_map[0], size / Z2RAM_CHUNKSIZE);
+			if (z2ram_map == NULL) {
+				printk(KERN_ERR DEVICE_NAME
+				       ": cannot get mem for z2ram_map\n");
+				goto err_out;
+			}
+
+			while (size) {
+				z2ram_map[z2ram_size++] = vaddr;
+				size -= Z2RAM_CHUNKSIZE;
+				vaddr += Z2RAM_CHUNKSIZE;
+				list_count++;
+			}
+
+			if (z2ram_size != 0)
+				printk(KERN_INFO DEVICE_NAME
+				       ": using %iK List Entry %d Memory\n",
+				       list_count * Z2RAM_CHUNK1024, index);
+		} else
+			switch (device) {
+			case Z2MINOR_COMBINED:
+
+				z2ram_map =
+				    kmalloc(max_z2_map + max_chip_map,
+					    GFP_KERNEL);
+				if (z2ram_map == NULL) {
+					printk(KERN_ERR DEVICE_NAME
+					       ": cannot get mem for z2ram_map\n");
+					goto err_out;
+				}
+
+				get_z2ram();
+				get_chipram();
+
+				if (z2ram_size != 0)
+					printk(KERN_INFO DEVICE_NAME
+					       ": using %iK Zorro II RAM and %iK Chip RAM (Total %dK)\n",
+					       z2_count * Z2RAM_CHUNK1024,
+					       chip_count * Z2RAM_CHUNK1024,
+					       (z2_count +
+						chip_count) * Z2RAM_CHUNK1024);
+
+				break;
+
+			case Z2MINOR_Z2ONLY:
+				z2ram_map = kmalloc(max_z2_map, GFP_KERNEL);
+				if (!z2ram_map)
+					goto err_out;
+
+				get_z2ram();
+
+				if (z2ram_size != 0)
+					printk(KERN_INFO DEVICE_NAME
+					       ": using %iK of Zorro II RAM\n",
+					       z2_count * Z2RAM_CHUNK1024);
+
+				break;
+
+			case Z2MINOR_CHIPONLY:
+				z2ram_map = kmalloc(max_chip_map, GFP_KERNEL);
+				if (!z2ram_map)
+					goto err_out;
+
+				get_chipram();
+
+				if (z2ram_size != 0)
+					printk(KERN_INFO DEVICE_NAME
+					       ": using %iK Chip RAM\n",
+					       chip_count * Z2RAM_CHUNK1024);
+
+				break;
+
+			default:
+				rc = -ENODEV;
+				goto err_out;
+
+				break;
+			}
+
+		if (z2ram_size == 0) {
+			printk(KERN_NOTICE DEVICE_NAME
+			       ": no unused ZII/Chip RAM found\n");
+			goto err_out_kfree;
+		}
+
+		current_device = device;
+		z2ram_size <<= Z2RAM_CHUNKSHIFT;
+		set_capacity(z2ram_gendisk[device], z2ram_size >> 9);
+	}
+
+	mutex_unlock(&z2ram_mutex);
+	return 0;
+
+err_out_kfree:
+	kfree(z2ram_map);
+err_out:
+	mutex_unlock(&z2ram_mutex);
+	return rc;
+}
+
+static void z2_release(struct gendisk *disk)
+{
+	mutex_lock(&z2ram_mutex);
+	if (current_device == -1) {
+		mutex_unlock(&z2ram_mutex);
+		return;
+	}
+	mutex_unlock(&z2ram_mutex);
+	/*
+	 * FIXME: unmap memory
+	 */
+}
+
+static const struct block_device_operations z2_fops = {
+	.owner = THIS_MODULE,
+	.open = z2_open,
+	.release = z2_release,
+};
+
+static struct blk_mq_tag_set tag_set;
+
+static const struct blk_mq_ops z2_mq_ops = {
+	.queue_rq = z2_queue_rq,
+};
+
+static int z2ram_register_disk(int minor)
+{
+	struct gendisk *disk;
+	int err;
+
+	disk = blk_mq_alloc_disk(&tag_set, NULL, NULL);
+	if (IS_ERR(disk))
+		return PTR_ERR(disk);
+
+	disk->major = Z2RAM_MAJOR;
+	disk->first_minor = minor;
+	disk->minors = 1;
+	disk->flags |= GENHD_FL_NO_PART;
+	disk->fops = &z2_fops;
+	if (minor)
+		sprintf(disk->disk_name, "z2ram%d", minor);
+	else
+		sprintf(disk->disk_name, "z2ram");
+
+	z2ram_gendisk[minor] = disk;
+	err = add_disk(disk);
+	if (err)
+		put_disk(disk);
+	return err;
+}
+
+static int __init z2_init(void)
+{
+	int ret, i;
+
+	if (!MACH_IS_AMIGA)
+		return -ENODEV;
+
+	if (register_blkdev(Z2RAM_MAJOR, DEVICE_NAME))
+		return -EBUSY;
+
+	tag_set.ops = &z2_mq_ops;
+	tag_set.nr_hw_queues = 1;
+	tag_set.nr_maps = 1;
+	tag_set.queue_depth = 16;
+	tag_set.numa_node = NUMA_NO_NODE;
+	ret = blk_mq_alloc_tag_set(&tag_set);
+	if (ret)
+		goto out_unregister_blkdev;
+
+	for (i = 0; i < Z2MINOR_COUNT; i++) {
+		ret = z2ram_register_disk(i);
+		if (ret && i == 0)
+			goto out_free_tagset;
+	}
+
+	return 0;
+
+out_free_tagset:
+	blk_mq_free_tag_set(&tag_set);
+out_unregister_blkdev:
+	unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
+	return ret;
+}
+
+static void __exit z2_exit(void)
+{
+	int i, j;
+
+	unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
+
+	for (i = 0; i < Z2MINOR_COUNT; i++) {
+		del_gendisk(z2ram_gendisk[i]);
+		put_disk(z2ram_gendisk[i]);
+	}
+	blk_mq_free_tag_set(&tag_set);
+
+	if (current_device != -1) {
+		i = 0;
+
+		for (j = 0; j < z2_count; j++) {
+			set_bit(i++, zorro_unused_z2ram);
+		}
+
+		for (j = 0; j < chip_count; j++) {
+			if (z2ram_map[i]) {
+				amiga_chip_free((void *)z2ram_map[i++]);
+			}
+		}
+
+		if (z2ram_map != NULL) {
+			kfree(z2ram_map);
+		}
+	}
+
+	return;
+}
+
+module_init(z2_init);
+module_exit(z2_exit);
+MODULE_DESCRIPTION("Amiga Zorro II ramdisk driver");
+MODULE_LICENSE("GPL");