From 106b4a2a78b2a2f14885604891957b84bba502db Mon Sep 17 00:00:00 2001 From: Adrian Betschart Date: Fri, 11 Sep 2026 17:13:14 +0200 Subject: drm/amd/display: Try RGB before YCbCr 4:4:4 in stream validation 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 Assisted-by: Claude Code:claude-fable-5-1 Signed-off-by: Adrian Betschart Reviewed-by: Fangzhi Zuo Tested-by: Adolfo Rodrigues Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 7de432bc753133764dc40d37f9388da56de251e7) --- drivers/tty/serial/liteuart.c | 478 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 478 insertions(+) create mode 100644 drivers/tty/serial/liteuart.c (limited to 'drivers/tty/serial/liteuart.c') diff --git a/drivers/tty/serial/liteuart.c b/drivers/tty/serial/liteuart.c new file mode 100644 index 000000000..6429e8f11 --- /dev/null +++ b/drivers/tty/serial/liteuart.c @@ -0,0 +1,478 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * LiteUART serial controller (LiteX) Driver + * + * Copyright (C) 2019-2020 Antmicro + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * CSRs definitions (base address offsets + width) + * + * The definitions below are true for LiteX SoC configured for 8-bit CSR Bus, + * 32-bit aligned. + * + * Supporting other configurations might require new definitions or a more + * generic way of indexing the LiteX CSRs. + * + * For more details on how CSRs are defined and handled in LiteX, see comments + * in the LiteX SoC Driver: drivers/soc/litex/litex_soc_ctrl.c + */ +#define OFF_RXTX 0x00 +#define OFF_TXFULL 0x04 +#define OFF_RXEMPTY 0x08 +#define OFF_EV_STATUS 0x0c +#define OFF_EV_PENDING 0x10 +#define OFF_EV_ENABLE 0x14 + +/* events */ +#define EV_TX BIT(0) +#define EV_RX BIT(1) + +struct liteuart_port { + struct uart_port port; + struct timer_list timer; + u8 irq_reg; +}; + +#define to_liteuart_port(port) container_of(port, struct liteuart_port, port) + +static DEFINE_XARRAY_FLAGS(liteuart_array, XA_FLAGS_ALLOC); + +#ifdef CONFIG_SERIAL_LITEUART_CONSOLE +static struct console liteuart_console; +#endif + +static struct uart_driver liteuart_driver = { + .owner = THIS_MODULE, + .driver_name = KBUILD_MODNAME, + .dev_name = "ttyLXU", + .major = 0, + .minor = 0, + .nr = CONFIG_SERIAL_LITEUART_MAX_PORTS, +#ifdef CONFIG_SERIAL_LITEUART_CONSOLE + .cons = &liteuart_console, +#endif +}; + +static void liteuart_update_irq_reg(struct uart_port *port, bool set, u8 mask) +{ + struct liteuart_port *uart = to_liteuart_port(port); + + if (set) + uart->irq_reg |= mask; + else + uart->irq_reg &= ~mask; + + if (port->irq) + litex_write8(port->membase + OFF_EV_ENABLE, uart->irq_reg); +} + +static void liteuart_stop_tx(struct uart_port *port) +{ + liteuart_update_irq_reg(port, false, EV_TX); +} + +static void liteuart_start_tx(struct uart_port *port) +{ + liteuart_update_irq_reg(port, true, EV_TX); +} + +static void liteuart_stop_rx(struct uart_port *port) +{ + struct liteuart_port *uart = to_liteuart_port(port); + + /* just delete timer */ + timer_delete(&uart->timer); +} + +static void liteuart_rx_chars(struct uart_port *port) +{ + unsigned char __iomem *membase = port->membase; + u8 ch; + + while (!litex_read8(membase + OFF_RXEMPTY)) { + ch = litex_read8(membase + OFF_RXTX); + port->icount.rx++; + + /* necessary for RXEMPTY to refresh its value */ + litex_write8(membase + OFF_EV_PENDING, EV_RX); + + /* no overflow bits in status */ + if (!(uart_handle_sysrq_char(port, ch))) + uart_insert_char(port, 1, 0, ch, TTY_NORMAL); + } + + tty_flip_buffer_push(&port->state->port); +} + +static void liteuart_tx_chars(struct uart_port *port) +{ + u8 ch; + + uart_port_tx(port, ch, + !litex_read8(port->membase + OFF_TXFULL), + litex_write8(port->membase + OFF_RXTX, ch)); +} + +static irqreturn_t liteuart_interrupt(int irq, void *data) +{ + struct liteuart_port *uart = data; + struct uart_port *port = &uart->port; + unsigned long flags; + u8 isr; + + /* + * if polling, the context would be "in_serving_softirq", so use + * irq[save|restore] spin_lock variants to cover all possibilities + */ + uart_port_lock_irqsave(port, &flags); + isr = litex_read8(port->membase + OFF_EV_PENDING) & uart->irq_reg; + if (isr & EV_RX) + liteuart_rx_chars(port); + if (isr & EV_TX) + liteuart_tx_chars(port); + uart_port_unlock_irqrestore(port, flags); + + return IRQ_RETVAL(isr); +} + +static void liteuart_timer(struct timer_list *t) +{ + struct liteuart_port *uart = timer_container_of(uart, t, timer); + struct uart_port *port = &uart->port; + + liteuart_interrupt(0, port); + mod_timer(&uart->timer, jiffies + uart_poll_timeout(port)); +} + +static unsigned int liteuart_tx_empty(struct uart_port *port) +{ + /* not really tx empty, just checking if tx is not full */ + if (!litex_read8(port->membase + OFF_TXFULL)) + return TIOCSER_TEMT; + + return 0; +} + +static void liteuart_set_mctrl(struct uart_port *port, unsigned int mctrl) +{ + /* modem control register is not present in LiteUART */ +} + +static unsigned int liteuart_get_mctrl(struct uart_port *port) +{ + return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR; +} + +static int liteuart_startup(struct uart_port *port) +{ + struct liteuart_port *uart = to_liteuart_port(port); + unsigned long flags; + int ret; + + if (port->irq) { + ret = request_irq(port->irq, liteuart_interrupt, 0, + KBUILD_MODNAME, uart); + if (ret) { + dev_warn(port->dev, + "line %d irq %d failed: switch to polling\n", + port->line, port->irq); + port->irq = 0; + } + } + + uart_port_lock_irqsave(port, &flags); + /* only enabling rx irqs during startup */ + liteuart_update_irq_reg(port, true, EV_RX); + uart_port_unlock_irqrestore(port, flags); + + if (!port->irq) { + timer_setup(&uart->timer, liteuart_timer, 0); + mod_timer(&uart->timer, jiffies + uart_poll_timeout(port)); + } + + return 0; +} + +static void liteuart_shutdown(struct uart_port *port) +{ + struct liteuart_port *uart = to_liteuart_port(port); + unsigned long flags; + + uart_port_lock_irqsave(port, &flags); + liteuart_update_irq_reg(port, false, EV_RX | EV_TX); + uart_port_unlock_irqrestore(port, flags); + + if (port->irq) + free_irq(port->irq, port); + else + timer_delete_sync(&uart->timer); +} + +static void liteuart_set_termios(struct uart_port *port, struct ktermios *new, + const struct ktermios *old) +{ + unsigned int baud; + unsigned long flags; + + uart_port_lock_irqsave(port, &flags); + + /* update baudrate */ + baud = uart_get_baud_rate(port, new, old, 0, 460800); + uart_update_timeout(port, new->c_cflag, baud); + + uart_port_unlock_irqrestore(port, flags); +} + +static const char *liteuart_type(struct uart_port *port) +{ + return "liteuart"; +} + +static void liteuart_config_port(struct uart_port *port, int flags) +{ + /* + * Driver core for serial ports forces a non-zero value for port type. + * Write an arbitrary value here to accommodate the serial core driver, + * as ID part of UAPI is redundant. + */ + port->type = 1; +} + +static int liteuart_verify_port(struct uart_port *port, + struct serial_struct *ser) +{ + if (port->type != PORT_UNKNOWN && ser->type != 1) + return -EINVAL; + + return 0; +} + +static const struct uart_ops liteuart_ops = { + .tx_empty = liteuart_tx_empty, + .set_mctrl = liteuart_set_mctrl, + .get_mctrl = liteuart_get_mctrl, + .stop_tx = liteuart_stop_tx, + .start_tx = liteuart_start_tx, + .stop_rx = liteuart_stop_rx, + .startup = liteuart_startup, + .shutdown = liteuart_shutdown, + .set_termios = liteuart_set_termios, + .type = liteuart_type, + .config_port = liteuart_config_port, + .verify_port = liteuart_verify_port, +}; + +static int liteuart_probe(struct platform_device *pdev) +{ + struct liteuart_port *uart; + struct uart_port *port; + struct xa_limit limit; + int dev_id, ret; + + uart = devm_kzalloc(&pdev->dev, sizeof(struct liteuart_port), GFP_KERNEL); + if (!uart) + return -ENOMEM; + + port = &uart->port; + + /* get membase */ + port->membase = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); + if (IS_ERR(port->membase)) + return PTR_ERR(port->membase); + + ret = platform_get_irq_optional(pdev, 0); + if (ret < 0 && ret != -ENXIO) + return ret; + if (ret > 0) + port->irq = ret; + + /* look for aliases; auto-enumerate for free index if not found */ + dev_id = of_alias_get_id(pdev->dev.of_node, "serial"); + if (dev_id < 0) + limit = XA_LIMIT(0, CONFIG_SERIAL_LITEUART_MAX_PORTS); + else + limit = XA_LIMIT(dev_id, dev_id); + + ret = xa_alloc(&liteuart_array, &dev_id, uart, limit, GFP_KERNEL); + if (ret) + return ret; + + /* values not from device tree */ + port->dev = &pdev->dev; + port->iotype = UPIO_MEM; + port->flags = UPF_BOOT_AUTOCONF; + port->ops = &liteuart_ops; + port->fifosize = 16; + port->type = PORT_UNKNOWN; + port->line = dev_id; + spin_lock_init(&port->lock); + + platform_set_drvdata(pdev, port); + + ret = uart_add_one_port(&liteuart_driver, &uart->port); + if (ret) + goto err_erase_id; + + return 0; + +err_erase_id: + xa_erase(&liteuart_array, dev_id); + + return ret; +} + +static void liteuart_remove(struct platform_device *pdev) +{ + struct uart_port *port = platform_get_drvdata(pdev); + unsigned int line = port->line; + + uart_remove_one_port(&liteuart_driver, port); + xa_erase(&liteuart_array, line); +} + +static const struct of_device_id liteuart_of_match[] = { + { .compatible = "litex,liteuart" }, + {} +}; +MODULE_DEVICE_TABLE(of, liteuart_of_match); + +static struct platform_driver liteuart_platform_driver = { + .probe = liteuart_probe, + .remove = liteuart_remove, + .driver = { + .name = KBUILD_MODNAME, + .of_match_table = liteuart_of_match, + }, +}; + +#ifdef CONFIG_SERIAL_LITEUART_CONSOLE + +static void liteuart_putchar(struct uart_port *port, unsigned char ch) +{ + while (litex_read8(port->membase + OFF_TXFULL)) + cpu_relax(); + + litex_write8(port->membase + OFF_RXTX, ch); +} + +static void liteuart_console_write(struct console *co, const char *s, + unsigned int count) +{ + struct liteuart_port *uart; + struct uart_port *port; + unsigned long flags; + + uart = (struct liteuart_port *)xa_load(&liteuart_array, co->index); + port = &uart->port; + + uart_port_lock_irqsave(port, &flags); + uart_console_write(port, s, count, liteuart_putchar); + uart_port_unlock_irqrestore(port, flags); +} + +static int liteuart_console_setup(struct console *co, char *options) +{ + struct liteuart_port *uart; + struct uart_port *port; + int baud = 115200; + int bits = 8; + int parity = 'n'; + int flow = 'n'; + + uart = (struct liteuart_port *)xa_load(&liteuart_array, co->index); + if (!uart) + return -ENODEV; + + port = &uart->port; + if (!port->membase) + return -ENODEV; + + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + + return uart_set_options(port, co, baud, parity, bits, flow); +} + +static struct console liteuart_console = { + .name = KBUILD_MODNAME, + .write = liteuart_console_write, + .device = uart_console_device, + .setup = liteuart_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &liteuart_driver, +}; + +static int __init liteuart_console_init(void) +{ + register_console(&liteuart_console); + + return 0; +} +console_initcall(liteuart_console_init); + +static void early_liteuart_write(struct console *console, const char *s, + unsigned int count) +{ + struct earlycon_device *device = console->data; + struct uart_port *port = &device->port; + + uart_console_write(port, s, count, liteuart_putchar); +} + +static int __init early_liteuart_setup(struct earlycon_device *device, + const char *options) +{ + if (!device->port.membase) + return -ENODEV; + + device->con->write = early_liteuart_write; + return 0; +} + +OF_EARLYCON_DECLARE(liteuart, "litex,liteuart", early_liteuart_setup); +#endif /* CONFIG_SERIAL_LITEUART_CONSOLE */ + +static int __init liteuart_init(void) +{ + int res; + + res = uart_register_driver(&liteuart_driver); + if (res) + return res; + + res = platform_driver_register(&liteuart_platform_driver); + if (res) + uart_unregister_driver(&liteuart_driver); + + return res; +} + +static void __exit liteuart_exit(void) +{ + platform_driver_unregister(&liteuart_platform_driver); + uart_unregister_driver(&liteuart_driver); +} + +module_init(liteuart_init); +module_exit(liteuart_exit); + +MODULE_AUTHOR("Antmicro "); +MODULE_DESCRIPTION("LiteUART serial driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:liteuart"); -- cgit v1.3.1