1 // SPDX-License-Identifier: GPL-2.0
7  *  Serial driver for BCM63xx integrated UART.
23 #include <linux/serial.h>
37  *  - rx fifo full
38  *  - rx fifo above threshold
39  *  - rx fifo not empty for too long
53  * - tx fifo empty
54  * - tx fifo below threshold
76 	return __raw_readl(port->membase + offset);  in bcm_uart_readl()
82 	__raw_writel(value, port->membase + offset);  in bcm_uart_writel()
86  * serial core request to check if uart tx fifo is empty
97  * serial core request to set RTS and DTR pin state and loopback mode
121  * serial core request to return RI, CTS, DCD and DSR pin state
141  * serial core request to disable tx ASAP (used for flow control)
157  * serial core request to (re)enable tx
173  * serial core request to stop rx, called before port shutdown
185  * serial core request to enable modem status interrupt reporting
197  * serial core request to start/stop emitting break char
221 	return (port->type == PORT_BCM63XX) ? "bcm63xx_uart" : NULL;  in bcm_uart_type()
229 	struct tty_port *tty_port = &port->state->port;  in bcm_uart_do_rx()
234 	 * serial port */  in bcm_uart_do_rx()
253 			port->icount.overrun++;  in bcm_uart_do_rx()
261 		port->icount.rx++;  in bcm_uart_do_rx()
268 				port->icount.brk++;  in bcm_uart_do_rx()
274 				port->icount.parity++;  in bcm_uart_do_rx()
276 				port->icount.frame++;  in bcm_uart_do_rx()
279 			cstat &= port->read_status_mask;  in bcm_uart_do_rx()
292 		if ((cstat & port->ignore_status_mask) == 0)  in bcm_uart_do_rx()
295 	} while (--max_count);  in bcm_uart_do_rx()
313 	pending = uart_port_tx_limited(port, ch, port->fifosize - val,  in bcm_uart_do_tx()
403  * serial core request to initialize uart and start rx operation
421 	val |= (port->fifosize / 2) << UART_MCTL_RXFIFOTHRESH_SHIFT;  in bcm_uart_startup()
422 	val |= (port->fifosize / 2) << UART_MCTL_TXFIFOTHRESH_SHIFT;  in bcm_uart_startup()
438 	ret = request_irq(port->irq, bcm_uart_interrupt, 0,  in bcm_uart_startup()
439 			  dev_name(port->dev), port);  in bcm_uart_startup()
448  * serial core request to flush & disable uart
460 	free_irq(port->irq, port);  in bcm_uart_shutdown()
464  * serial core request to change current uart setting
476 	for (tries = 3; !bcm_uart_tx_empty(port) && tries; tries--)  in bcm_uart_set_termios()
487 	switch (new->c_cflag & CSIZE) {  in bcm_uart_set_termios()
503 	if (new->c_cflag & CSTOPB)  in bcm_uart_set_termios()
509 	if (new->c_cflag & PARENB)  in bcm_uart_set_termios()
512 	if (new->c_cflag & PARODD)  in bcm_uart_set_termios()
517 	baud = uart_get_baud_rate(port, new, old, 0, port->uartclk / 16);  in bcm_uart_set_termios()
518 	quot = uart_get_divisor(port, baud) - 1;  in bcm_uart_set_termios()
525 	if (UART_ENABLE_MS(port, new->c_cflag))  in bcm_uart_set_termios()
531 	port->read_status_mask = UART_FIFO_VALID_MASK;  in bcm_uart_set_termios()
532 	if (new->c_iflag & INPCK) {  in bcm_uart_set_termios()
533 		port->read_status_mask |= UART_FIFO_FRAMEERR_MASK;  in bcm_uart_set_termios()
534 		port->read_status_mask |= UART_FIFO_PARERR_MASK;  in bcm_uart_set_termios()
536 	if (new->c_iflag & (IGNBRK | BRKINT))  in bcm_uart_set_termios()
537 		port->read_status_mask |= UART_FIFO_BRKDET_MASK;  in bcm_uart_set_termios()
539 	port->ignore_status_mask = 0;  in bcm_uart_set_termios()
540 	if (new->c_iflag & IGNPAR)  in bcm_uart_set_termios()
541 		port->ignore_status_mask |= UART_FIFO_PARERR_MASK;  in bcm_uart_set_termios()
542 	if (new->c_iflag & IGNBRK)  in bcm_uart_set_termios()
543 		port->ignore_status_mask |= UART_FIFO_BRKDET_MASK;  in bcm_uart_set_termios()
544 	if (!(new->c_cflag & CREAD))  in bcm_uart_set_termios()
545 		port->ignore_status_mask |= UART_FIFO_VALID_MASK;  in bcm_uart_set_termios()
547 	uart_update_timeout(port, new->c_cflag, baud);  in bcm_uart_set_termios()
553  * serial core request to claim uart iomem
562  * serial core request to release uart iomem
570  * serial core request to do any port required autoconfiguration
577 		port->type = PORT_BCM63XX;  in bcm_uart_config_port()
582  * serial core request to check that port information in serinfo are
588 	if (port->type != PORT_BCM63XX)  in bcm_uart_verify_port()
589 		return -EINVAL;  in bcm_uart_verify_port()
590 	if (port->irq != serinfo->irq)  in bcm_uart_verify_port()
591 		return -EINVAL;  in bcm_uart_verify_port()
592 	if (port->iotype != serinfo->io_type)  in bcm_uart_verify_port()
593 		return -EINVAL;  in bcm_uart_verify_port()
594 	if (port->mapbase != (unsigned long)serinfo->iomem_base)  in bcm_uart_verify_port()
595 		return -EINVAL;  in bcm_uart_verify_port()
609 	return !(port->fifosize - val);  in bcm_uart_tx_full()
633 /* serial core callbacks */
666 	while (--tmout) {  in wait_for_xmitr()
676 	if (port->flags & UPF_CONS_FLOW) {  in wait_for_xmitr()
678 		while (--tmout) {  in wait_for_xmitr()
708 	port = &ports[co->index];  in bcm_console_write()
711 	if (port->sysrq) {  in bcm_console_write()
744 	if (co->index < 0 || co->index >= BCM63XX_NR_UARTS)  in bcm_console_setup()
745 		return -EINVAL;  in bcm_console_setup()
746 	port = &ports[co->index];  in bcm_console_setup()
747 	if (!port->membase)  in bcm_console_setup()
748 		return -ENODEV;  in bcm_console_setup()
763 	.index		= -1,
777 	struct earlycon_device *dev = con->data;  in bcm_early_write()
779 	uart_console_write(&dev->port, s, n, bcm_console_putchar);  in bcm_early_write()
780 	wait_for_xmitr(&dev->port);  in bcm_early_write()
786 	if (!device->port.membase)  in bcm_early_console_setup()
787 		return -ENODEV;  in bcm_early_console_setup()
789 	device->con->write = bcm_early_write;  in bcm_early_console_setup()
793 OF_EARLYCON_DECLARE(bcm63xx_uart, "brcm,bcm6345-uart", bcm_early_console_setup);
820 	if (pdev->dev.of_node) {  in bcm_uart_probe()
821 		pdev->id = of_alias_get_id(pdev->dev.of_node, "serial");  in bcm_uart_probe()
823 		if (pdev->id < 0)  in bcm_uart_probe()
824 			pdev->id = of_alias_get_id(pdev->dev.of_node, "uart");  in bcm_uart_probe()
827 	if (pdev->id < 0 || pdev->id >= BCM63XX_NR_UARTS)  in bcm_uart_probe()
828 		return -EINVAL;  in bcm_uart_probe()
830 	port = &ports[pdev->id];  in bcm_uart_probe()
831 	if (port->membase)  in bcm_uart_probe()
832 		return -EBUSY;  in bcm_uart_probe()
835 	port->membase = devm_platform_get_and_ioremap_resource(pdev, 0, &res_mem);  in bcm_uart_probe()
836 	if (IS_ERR(port->membase))  in bcm_uart_probe()
837 		return PTR_ERR(port->membase);  in bcm_uart_probe()
838 	port->mapbase = res_mem->start;  in bcm_uart_probe()
843 	port->irq = ret;  in bcm_uart_probe()
845 	clk = clk_get(&pdev->dev, "refclk");  in bcm_uart_probe()
846 	if (IS_ERR(clk) && pdev->dev.of_node)  in bcm_uart_probe()
847 		clk = of_clk_get(pdev->dev.of_node, 0);  in bcm_uart_probe()
850 		return -ENODEV;  in bcm_uart_probe()
852 	port->iotype = UPIO_MEM;  in bcm_uart_probe()
853 	port->ops = &bcm_uart_ops;  in bcm_uart_probe()
854 	port->flags = UPF_BOOT_AUTOCONF;  in bcm_uart_probe()
855 	port->dev = &pdev->dev;  in bcm_uart_probe()
856 	port->fifosize = 16;  in bcm_uart_probe()
857 	port->uartclk = clk_get_rate(clk) / 2;  in bcm_uart_probe()
858 	port->line = pdev->id;  in bcm_uart_probe()
859 	port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_BCM63XX_CONSOLE);  in bcm_uart_probe()
864 		ports[pdev->id].membase = NULL;  in bcm_uart_probe()
878 	ports[pdev->id].membase = NULL;  in bcm_uart_remove()
882 	{ .compatible = "brcm,bcm6345-uart" },