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, 506 insertions, 0 deletions

diff --git a/drivers/mfd/macsmc.c b/drivers/mfd/macsmc.c
new file mode 100644
index 000000000..514cba7dc
--- /dev/null
+++ b/drivers/mfd/macsmc.c
@@ -0,0 +1,506 @@
+// SPDX-License-Identifier: GPL-2.0-only OR MIT
+/*
+ * Apple SMC (System Management Controller) MFD driver
+ *
+ * Copyright The Asahi Linux Contributors
+ */
+
+#include <linux/bitfield.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/math.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/macsmc.h>
+#include <linux/notifier.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/overflow.h>
+#include <linux/platform_device.h>
+#include <linux/soc/apple/rtkit.h>
+#include <linux/unaligned.h>
+
+#define SMC_ENDPOINT			0x20
+
+/* We don't actually know the true size here but this seem reasonable */
+#define SMC_SHMEM_SIZE			0x1000
+#define SMC_MAX_SIZE			255
+
+#define SMC_MSG_READ_KEY		0x10
+#define SMC_MSG_WRITE_KEY		0x11
+#define SMC_MSG_GET_KEY_BY_INDEX	0x12
+#define SMC_MSG_GET_KEY_INFO		0x13
+#define SMC_MSG_INITIALIZE		0x17
+#define SMC_MSG_NOTIFICATION		0x18
+#define SMC_MSG_RW_KEY			0x20
+
+#define SMC_DATA			GENMASK_ULL(63, 32)
+#define SMC_WSIZE			GENMASK_ULL(31, 24)
+#define SMC_SIZE			GENMASK_ULL(23, 16)
+#define SMC_ID				GENMASK_ULL(15, 12)
+#define SMC_MSG				GENMASK_ULL(7, 0)
+#define SMC_RESULT			SMC_MSG
+
+#define SMC_TIMEOUT_MS		500
+
+static const struct mfd_cell apple_smc_devs[] = {
+	MFD_CELL_NAME("macsmc-input"),
+	MFD_CELL_NAME("macsmc-power"),
+	MFD_CELL_OF("macsmc-gpio", NULL, NULL, 0, 0, "apple,smc-gpio"),
+	MFD_CELL_OF("macsmc-hwmon", NULL, NULL, 0, 0, "apple,smc-hwmon"),
+	MFD_CELL_OF("macsmc-reboot", NULL, NULL, 0, 0, "apple,smc-reboot"),
+	MFD_CELL_OF("macsmc-rtc", NULL, NULL, 0, 0, "apple,smc-rtc"),
+};
+
+static int apple_smc_cmd_locked(struct apple_smc *smc, u64 cmd, u64 arg,
+				  u64 size, u64 wsize, u32 *ret_data)
+{
+	u8 result;
+	int ret;
+	u64 msg;
+
+	lockdep_assert_held(&smc->mutex);
+
+	if (smc->boot_stage != APPLE_SMC_INITIALIZED)
+		return -EIO;
+	if (smc->atomic_mode)
+		return -EIO;
+
+	reinit_completion(&smc->cmd_done);
+
+	smc->msg_id = (smc->msg_id + 1) & 0xf;
+	msg = (FIELD_PREP(SMC_MSG, cmd) |
+	       FIELD_PREP(SMC_SIZE, size) |
+	       FIELD_PREP(SMC_WSIZE, wsize) |
+	       FIELD_PREP(SMC_ID, smc->msg_id) |
+	       FIELD_PREP(SMC_DATA, arg));
+
+	ret = apple_rtkit_send_message(smc->rtk, SMC_ENDPOINT, msg, NULL, false);
+	if (ret) {
+		dev_err(smc->dev, "Failed to send command\n");
+		return ret;
+	}
+
+	if (wait_for_completion_timeout(&smc->cmd_done, msecs_to_jiffies(SMC_TIMEOUT_MS)) <= 0) {
+		dev_err(smc->dev, "Command timed out (%llx)", msg);
+		return -ETIMEDOUT;
+	}
+
+	if (FIELD_GET(SMC_ID, smc->cmd_ret) != smc->msg_id) {
+		dev_err(smc->dev, "Command sequence mismatch (expected %d, got %d)\n",
+			smc->msg_id, (unsigned int)FIELD_GET(SMC_ID, smc->cmd_ret));
+		return -EIO;
+	}
+
+	result = FIELD_GET(SMC_RESULT, smc->cmd_ret);
+	if (result)
+		return -EIO;
+
+	if (ret_data)
+		*ret_data = FIELD_GET(SMC_DATA, smc->cmd_ret);
+
+	return FIELD_GET(SMC_SIZE, smc->cmd_ret);
+}
+
+static int apple_smc_cmd(struct apple_smc *smc, u64 cmd, u64 arg,
+			 u64 size, u64 wsize, u32 *ret_data)
+{
+	guard(mutex)(&smc->mutex);
+
+	return apple_smc_cmd_locked(smc, cmd, arg, size, wsize, ret_data);
+}
+
+static int apple_smc_rw_locked(struct apple_smc *smc, smc_key key,
+				const void *wbuf, size_t wsize,
+				void *rbuf, size_t rsize)
+{
+	u64 smc_size, smc_wsize;
+	u32 rdata;
+	int ret;
+	u64 cmd;
+
+	lockdep_assert_held(&smc->mutex);
+
+	if (rsize > SMC_MAX_SIZE)
+		return -EINVAL;
+	if (wsize > SMC_MAX_SIZE)
+		return -EINVAL;
+
+	if (rsize && wsize) {
+		cmd = SMC_MSG_RW_KEY;
+		memcpy_toio(smc->shmem.iomem, wbuf, wsize);
+		smc_size = rsize;
+		smc_wsize = wsize;
+	} else if (wsize && !rsize) {
+		cmd = SMC_MSG_WRITE_KEY;
+		memcpy_toio(smc->shmem.iomem, wbuf, wsize);
+		/*
+		 * Setting size to the length we want to write and wsize to 0
+		 * looks silly but that's how the SMC protocol works ¯\_(ツ)_/¯
+		 */
+		smc_size = wsize;
+		smc_wsize = 0;
+	} else if (!wsize && rsize) {
+		cmd = SMC_MSG_READ_KEY;
+		smc_size = rsize;
+		smc_wsize = 0;
+	} else {
+		return -EINVAL;
+	}
+
+	ret = apple_smc_cmd_locked(smc, cmd, key, smc_size, smc_wsize, &rdata);
+	if (ret < 0)
+		return ret;
+
+	if (rsize) {
+		/*
+		 * Small data <= 4 bytes is returned as part of the reply
+		 * message which is sent over the mailbox FIFO. Everything
+		 * bigger has to be copied from SRAM which is mapped as
+		 * Device memory.
+		 */
+		if (rsize <= 4)
+			memcpy(rbuf, &rdata, rsize);
+		else
+			memcpy_fromio(rbuf, smc->shmem.iomem, rsize);
+	}
+
+	return ret;
+}
+
+int apple_smc_read(struct apple_smc *smc, smc_key key, void *buf, size_t size)
+{
+	guard(mutex)(&smc->mutex);
+
+	return apple_smc_rw_locked(smc, key, NULL, 0, buf, size);
+}
+EXPORT_SYMBOL(apple_smc_read);
+
+int apple_smc_write(struct apple_smc *smc, smc_key key, const void *buf, size_t size)
+{
+	guard(mutex)(&smc->mutex);
+
+	return apple_smc_rw_locked(smc, key, buf, size, NULL, 0);
+}
+EXPORT_SYMBOL(apple_smc_write);
+
+int apple_smc_rw(struct apple_smc *smc, smc_key key, const void *wbuf, size_t wsize,
+		 void *rbuf, size_t rsize)
+{
+	guard(mutex)(&smc->mutex);
+
+	return apple_smc_rw_locked(smc, key, wbuf, wsize, rbuf, rsize);
+}
+EXPORT_SYMBOL(apple_smc_rw);
+
+int apple_smc_get_key_by_index(struct apple_smc *smc, int index, smc_key *key)
+{
+	int ret;
+
+	ret = apple_smc_cmd(smc, SMC_MSG_GET_KEY_BY_INDEX, index, 0, 0, key);
+
+	*key = swab32(*key);
+	return ret;
+}
+EXPORT_SYMBOL(apple_smc_get_key_by_index);
+
+int apple_smc_get_key_info(struct apple_smc *smc, smc_key key, struct apple_smc_key_info *info)
+{
+	u8 key_info[6];
+	int ret;
+
+	ret = apple_smc_cmd(smc, SMC_MSG_GET_KEY_INFO, key, 0, 0, NULL);
+	if (ret >= 0 && info) {
+		memcpy_fromio(key_info, smc->shmem.iomem, sizeof(key_info));
+		info->size = key_info[0];
+		info->type_code = get_unaligned_be32(&key_info[1]);
+		info->flags = key_info[5];
+	}
+	return ret;
+}
+EXPORT_SYMBOL(apple_smc_get_key_info);
+
+int apple_smc_enter_atomic(struct apple_smc *smc)
+{
+	guard(mutex)(&smc->mutex);
+
+	/*
+	 * Disable notifications since this is called before shutdown and no
+	 * notification handler will be able to handle the notification
+	 * using atomic operations only. Also ignore any failure here
+	 * because we're about to shut down or reboot anyway.
+	 * We can't use apple_smc_write_flag here since that would try to lock
+	 * smc->mutex again.
+	 */
+	const u8 flag = 0;
+
+	apple_smc_rw_locked(smc, SMC_KEY(NTAP), &flag, sizeof(flag), NULL, 0);
+
+	smc->atomic_mode = true;
+
+	return 0;
+}
+EXPORT_SYMBOL(apple_smc_enter_atomic);
+
+int apple_smc_write_atomic(struct apple_smc *smc, smc_key key, const void *buf, size_t size)
+{
+	guard(spinlock_irqsave)(&smc->lock);
+	u8 result;
+	int ret;
+	u64 msg;
+
+	if (size > SMC_MAX_SIZE || size == 0)
+		return -EINVAL;
+
+	if (smc->boot_stage != APPLE_SMC_INITIALIZED)
+		return -EIO;
+	if (!smc->atomic_mode)
+		return -EIO;
+
+	memcpy_toio(smc->shmem.iomem, buf, size);
+	smc->msg_id = (smc->msg_id + 1) & 0xf;
+	msg = (FIELD_PREP(SMC_MSG, SMC_MSG_WRITE_KEY) |
+	       FIELD_PREP(SMC_SIZE, size) |
+	       FIELD_PREP(SMC_ID, smc->msg_id) |
+	       FIELD_PREP(SMC_DATA, key));
+	smc->atomic_pending = true;
+
+	ret = apple_rtkit_send_message(smc->rtk, SMC_ENDPOINT, msg, NULL, true);
+	if (ret < 0) {
+		dev_err(smc->dev, "Failed to send command (%d)\n", ret);
+		return ret;
+	}
+
+	while (smc->atomic_pending) {
+		ret = apple_rtkit_poll(smc->rtk);
+		if (ret < 0) {
+			dev_err(smc->dev, "RTKit poll failed (%llx)", msg);
+			return ret;
+		}
+		udelay(100);
+	}
+
+	if (FIELD_GET(SMC_ID, smc->cmd_ret) != smc->msg_id) {
+		dev_err(smc->dev, "Command sequence mismatch (expected %d, got %d)\n",
+			smc->msg_id, (unsigned int)FIELD_GET(SMC_ID, smc->cmd_ret));
+		return -EIO;
+	}
+
+	result = FIELD_GET(SMC_RESULT, smc->cmd_ret);
+	if (result)
+		return -EIO;
+
+	return FIELD_GET(SMC_SIZE, smc->cmd_ret);
+}
+EXPORT_SYMBOL(apple_smc_write_atomic);
+
+static void apple_smc_rtkit_crashed(void *cookie, const void *bfr, size_t bfr_len)
+{
+	struct apple_smc *smc = cookie;
+
+	smc->boot_stage = APPLE_SMC_ERROR_CRASHED;
+	dev_err(smc->dev, "SMC crashed! Your system will reboot in a few seconds...\n");
+}
+
+static int apple_smc_rtkit_shmem_setup(void *cookie, struct apple_rtkit_shmem *bfr)
+{
+	struct apple_smc *smc = cookie;
+	size_t bfr_end;
+
+	if (!bfr->iova) {
+		dev_err(smc->dev, "RTKit wants a RAM buffer\n");
+		return -EIO;
+	}
+
+	if (check_add_overflow(bfr->iova, bfr->size - 1, &bfr_end))
+		return -EFAULT;
+
+	if (bfr->iova < smc->sram->start || bfr->iova > smc->sram->end ||
+	    bfr_end > smc->sram->end) {
+		dev_err(smc->dev, "RTKit buffer request outside SRAM region: [0x%llx, 0x%llx]\n",
+			(unsigned long long)bfr->iova,
+			(unsigned long long)bfr_end);
+		return -EFAULT;
+	}
+
+	bfr->iomem = smc->sram_base + (bfr->iova - smc->sram->start);
+	bfr->is_mapped = true;
+
+	return 0;
+}
+
+static bool apple_smc_rtkit_recv_early(void *cookie, u8 endpoint, u64 message)
+{
+	struct apple_smc *smc = cookie;
+
+	if (endpoint != SMC_ENDPOINT) {
+		dev_warn(smc->dev, "Received message for unknown endpoint 0x%x\n", endpoint);
+		return false;
+	}
+
+	if (smc->boot_stage == APPLE_SMC_BOOTING) {
+		int ret;
+
+		smc->shmem.iova = message;
+		smc->shmem.size = SMC_SHMEM_SIZE;
+		ret = apple_smc_rtkit_shmem_setup(smc, &smc->shmem);
+		if (ret < 0) {
+			smc->boot_stage = APPLE_SMC_ERROR_NO_SHMEM;
+			dev_err(smc->dev, "Failed to initialize shared memory (%d)\n", ret);
+		} else {
+			smc->boot_stage = APPLE_SMC_INITIALIZED;
+		}
+		complete(&smc->init_done);
+	} else if (FIELD_GET(SMC_MSG, message) == SMC_MSG_NOTIFICATION) {
+		/* Handle these in the RTKit worker thread */
+		return false;
+	} else {
+		smc->cmd_ret = message;
+		if (smc->atomic_pending)
+			smc->atomic_pending = false;
+		else
+			complete(&smc->cmd_done);
+	}
+
+	return true;
+}
+
+static void apple_smc_rtkit_recv(void *cookie, u8 endpoint, u64 message)
+{
+	struct apple_smc *smc = cookie;
+
+	if (endpoint != SMC_ENDPOINT) {
+		dev_warn(smc->dev, "Received message for unknown endpoint 0x%x\n", endpoint);
+		return;
+	}
+
+	if (FIELD_GET(SMC_MSG, message) != SMC_MSG_NOTIFICATION) {
+		dev_warn(smc->dev, "Received unknown message from worker: 0x%llx\n", message);
+		return;
+	}
+
+	blocking_notifier_call_chain(&smc->event_handlers, FIELD_GET(SMC_DATA, message), NULL);
+}
+
+static const struct apple_rtkit_ops apple_smc_rtkit_ops = {
+	.crashed = apple_smc_rtkit_crashed,
+	.recv_message = apple_smc_rtkit_recv,
+	.recv_message_early = apple_smc_rtkit_recv_early,
+	.shmem_setup = apple_smc_rtkit_shmem_setup,
+};
+
+static void apple_smc_rtkit_shutdown(void *data)
+{
+	struct apple_smc *smc = data;
+
+	/* Shut down SMC firmware, if it's not completely wedged */
+	if (apple_rtkit_is_running(smc->rtk))
+		apple_rtkit_quiesce(smc->rtk);
+}
+
+static void apple_smc_disable_notifications(void *data)
+{
+	struct apple_smc *smc = data;
+
+	apple_smc_write_flag(smc, SMC_KEY(NTAP), false);
+}
+
+static int apple_smc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct apple_smc *smc;
+	__be32 count;
+	int ret;
+
+	smc = devm_kzalloc(dev, sizeof(*smc), GFP_KERNEL);
+	if (!smc)
+		return -ENOMEM;
+
+	mutex_init(&smc->mutex);
+	smc->dev = &pdev->dev;
+	smc->sram_base = devm_platform_get_and_ioremap_resource(pdev, 1, &smc->sram);
+	if (IS_ERR(smc->sram_base))
+		return dev_err_probe(dev, PTR_ERR(smc->sram_base), "Failed to map SRAM region");
+
+	smc->rtk = devm_apple_rtkit_init(dev, smc, NULL, 0, &apple_smc_rtkit_ops);
+	if (IS_ERR(smc->rtk))
+		return dev_err_probe(dev, PTR_ERR(smc->rtk), "Failed to initialize RTKit");
+
+	smc->boot_stage = APPLE_SMC_BOOTING;
+	ret = apple_rtkit_wake(smc->rtk);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to wake up SMC");
+
+	ret = devm_add_action_or_reset(dev, apple_smc_rtkit_shutdown, smc);
+	if (ret)
+		return ret;
+
+	ret = apple_rtkit_start_ep(smc->rtk, SMC_ENDPOINT);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to start SMC endpoint");
+
+	init_completion(&smc->init_done);
+	init_completion(&smc->cmd_done);
+
+	ret = apple_rtkit_send_message(smc->rtk, SMC_ENDPOINT,
+				       FIELD_PREP(SMC_MSG, SMC_MSG_INITIALIZE), NULL, false);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to send init message");
+
+	if (wait_for_completion_timeout(&smc->init_done, msecs_to_jiffies(SMC_TIMEOUT_MS)) == 0) {
+		dev_err(dev, "Timed out initializing SMC");
+		return -ETIMEDOUT;
+	}
+
+	if (smc->boot_stage != APPLE_SMC_INITIALIZED) {
+		dev_err(dev, "SMC failed to boot successfully, boot stage=%d\n", smc->boot_stage);
+		return -EIO;
+	}
+
+	dev_set_drvdata(&pdev->dev, smc);
+	BLOCKING_INIT_NOTIFIER_HEAD(&smc->event_handlers);
+
+	ret = apple_smc_read(smc, SMC_KEY(#KEY), &count, sizeof(count));
+	if (ret >= 0 && ret != sizeof(count))
+		ret = -EINVAL;
+	if (ret < 0)
+		return dev_err_probe(smc->dev, ret, "Failed to get key count");
+	smc->key_count = be32_to_cpu(count);
+
+	/* Enable notifications */
+	apple_smc_write_flag(smc, SMC_KEY(NTAP), true);
+	ret = devm_add_action_or_reset(dev, apple_smc_disable_notifications, smc);
+	if (ret)
+		return ret;
+
+	ret = devm_mfd_add_devices(smc->dev, PLATFORM_DEVID_NONE,
+				   apple_smc_devs, ARRAY_SIZE(apple_smc_devs),
+				   NULL, 0, NULL);
+	if (ret)
+		return dev_err_probe(smc->dev, ret, "Failed to register sub-devices");
+
+
+	return 0;
+}
+
+static const struct of_device_id apple_smc_of_match[] = {
+	{ .compatible = "apple,t8103-smc" },
+	{ .compatible = "apple,smc" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, apple_smc_of_match);
+
+static struct platform_driver apple_smc_driver = {
+	.driver = {
+		.name = "macsmc",
+		.of_match_table = apple_smc_of_match,
+	},
+	.probe = apple_smc_probe,
+};
+module_platform_driver(apple_smc_driver);
+
+MODULE_AUTHOR("Hector Martin <marcan@marcan.st>");
+MODULE_AUTHOR("Sven Peter <sven@kernel.org>");
+MODULE_LICENSE("Dual MIT/GPL");
+MODULE_DESCRIPTION("Apple SMC driver");