Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 926 insertions, 0 deletions

diff --git a/drivers/tty/serial/bcm63xx_uart.c b/drivers/tty/serial/bcm63xx_uart.c
new file mode 100644
index 0000000000..0dd8cceb83
--- /dev/null
+++ b/drivers/tty/serial/bcm63xx_uart.c
@@ -0,0 +1,926 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Derived from many drivers using generic_serial interface.
+ *
+ * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
+ *
+ *  Serial driver for BCM63xx integrated UART.
+ *
+ * Hardware flow control was _not_ tested since I only have RX/TX on
+ * my board.
+ */
+
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/console.h>
+#include <linux/clk.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/sysrq.h>
+#include <linux/serial.h>
+#include <linux/serial_core.h>
+#include <linux/serial_bcm63xx.h>
+#include <linux/io.h>
+#include <linux/of.h>
+
+#define BCM63XX_NR_UARTS	2
+
+static struct uart_port ports[BCM63XX_NR_UARTS];
+
+/*
+ * rx interrupt mask / stat
+ *
+ * mask:
+ *  - rx fifo full
+ *  - rx fifo above threshold
+ *  - rx fifo not empty for too long
+ */
+#define UART_RX_INT_MASK	(UART_IR_MASK(UART_IR_RXOVER) |		\
+				UART_IR_MASK(UART_IR_RXTHRESH) |	\
+				UART_IR_MASK(UART_IR_RXTIMEOUT))
+
+#define UART_RX_INT_STAT	(UART_IR_STAT(UART_IR_RXOVER) |		\
+				UART_IR_STAT(UART_IR_RXTHRESH) |	\
+				UART_IR_STAT(UART_IR_RXTIMEOUT))
+
+/*
+ * tx interrupt mask / stat
+ *
+ * mask:
+ * - tx fifo empty
+ * - tx fifo below threshold
+ */
+#define UART_TX_INT_MASK	(UART_IR_MASK(UART_IR_TXEMPTY) |	\
+				UART_IR_MASK(UART_IR_TXTRESH))
+
+#define UART_TX_INT_STAT	(UART_IR_STAT(UART_IR_TXEMPTY) |	\
+				UART_IR_STAT(UART_IR_TXTRESH))
+
+/*
+ * external input interrupt
+ *
+ * mask: any edge on CTS, DCD
+ */
+#define UART_EXTINP_INT_MASK	(UART_EXTINP_IRMASK(UART_EXTINP_IR_CTS) | \
+				 UART_EXTINP_IRMASK(UART_EXTINP_IR_DCD))
+
+/*
+ * handy uart register accessor
+ */
+static inline unsigned int bcm_uart_readl(struct uart_port *port,
+					 unsigned int offset)
+{
+	return __raw_readl(port->membase + offset);
+}
+
+static inline void bcm_uart_writel(struct uart_port *port,
+				  unsigned int value, unsigned int offset)
+{
+	__raw_writel(value, port->membase + offset);
+}
+
+/*
+ * serial core request to check if uart tx fifo is empty
+ */
+static unsigned int bcm_uart_tx_empty(struct uart_port *port)
+{
+	unsigned int val;
+
+	val = bcm_uart_readl(port, UART_IR_REG);
+	return (val & UART_IR_STAT(UART_IR_TXEMPTY)) ? 1 : 0;
+}
+
+/*
+ * serial core request to set RTS and DTR pin state and loopback mode
+ */
+static void bcm_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+	unsigned int val;
+
+	val = bcm_uart_readl(port, UART_MCTL_REG);
+	val &= ~(UART_MCTL_DTR_MASK | UART_MCTL_RTS_MASK);
+	/* invert of written value is reflected on the pin */
+	if (!(mctrl & TIOCM_DTR))
+		val |= UART_MCTL_DTR_MASK;
+	if (!(mctrl & TIOCM_RTS))
+		val |= UART_MCTL_RTS_MASK;
+	bcm_uart_writel(port, val, UART_MCTL_REG);
+
+	val = bcm_uart_readl(port, UART_CTL_REG);
+	if (mctrl & TIOCM_LOOP)
+		val |= UART_CTL_LOOPBACK_MASK;
+	else
+		val &= ~UART_CTL_LOOPBACK_MASK;
+	bcm_uart_writel(port, val, UART_CTL_REG);
+}
+
+/*
+ * serial core request to return RI, CTS, DCD and DSR pin state
+ */
+static unsigned int bcm_uart_get_mctrl(struct uart_port *port)
+{
+	unsigned int val, mctrl;
+
+	mctrl = 0;
+	val = bcm_uart_readl(port, UART_EXTINP_REG);
+	if (val & UART_EXTINP_RI_MASK)
+		mctrl |= TIOCM_RI;
+	if (val & UART_EXTINP_CTS_MASK)
+		mctrl |= TIOCM_CTS;
+	if (val & UART_EXTINP_DCD_MASK)
+		mctrl |= TIOCM_CD;
+	if (val & UART_EXTINP_DSR_MASK)
+		mctrl |= TIOCM_DSR;
+	return mctrl;
+}
+
+/*
+ * serial core request to disable tx ASAP (used for flow control)
+ */
+static void bcm_uart_stop_tx(struct uart_port *port)
+{
+	unsigned int val;
+
+	val = bcm_uart_readl(port, UART_CTL_REG);
+	val &= ~(UART_CTL_TXEN_MASK);
+	bcm_uart_writel(port, val, UART_CTL_REG);
+
+	val = bcm_uart_readl(port, UART_IR_REG);
+	val &= ~UART_TX_INT_MASK;
+	bcm_uart_writel(port, val, UART_IR_REG);
+}
+
+/*
+ * serial core request to (re)enable tx
+ */
+static void bcm_uart_start_tx(struct uart_port *port)
+{
+	unsigned int val;
+
+	val = bcm_uart_readl(port, UART_IR_REG);
+	val |= UART_TX_INT_MASK;
+	bcm_uart_writel(port, val, UART_IR_REG);
+
+	val = bcm_uart_readl(port, UART_CTL_REG);
+	val |= UART_CTL_TXEN_MASK;
+	bcm_uart_writel(port, val, UART_CTL_REG);
+}
+
+/*
+ * serial core request to stop rx, called before port shutdown
+ */
+static void bcm_uart_stop_rx(struct uart_port *port)
+{
+	unsigned int val;
+
+	val = bcm_uart_readl(port, UART_IR_REG);
+	val &= ~UART_RX_INT_MASK;
+	bcm_uart_writel(port, val, UART_IR_REG);
+}
+
+/*
+ * serial core request to enable modem status interrupt reporting
+ */
+static void bcm_uart_enable_ms(struct uart_port *port)
+{
+	unsigned int val;
+
+	val = bcm_uart_readl(port, UART_IR_REG);
+	val |= UART_IR_MASK(UART_IR_EXTIP);
+	bcm_uart_writel(port, val, UART_IR_REG);
+}
+
+/*
+ * serial core request to start/stop emitting break char
+ */
+static void bcm_uart_break_ctl(struct uart_port *port, int ctl)
+{
+	unsigned long flags;
+	unsigned int val;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	val = bcm_uart_readl(port, UART_CTL_REG);
+	if (ctl)
+		val |= UART_CTL_XMITBRK_MASK;
+	else
+		val &= ~UART_CTL_XMITBRK_MASK;
+	bcm_uart_writel(port, val, UART_CTL_REG);
+
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+/*
+ * return port type in string format
+ */
+static const char *bcm_uart_type(struct uart_port *port)
+{
+	return (port->type == PORT_BCM63XX) ? "bcm63xx_uart" : NULL;
+}
+
+/*
+ * read all chars in rx fifo and send them to core
+ */
+static void bcm_uart_do_rx(struct uart_port *port)
+{
+	struct tty_port *tty_port = &port->state->port;
+	unsigned int max_count;
+
+	/* limit number of char read in interrupt, should not be
+	 * higher than fifo size anyway since we're much faster than
+	 * serial port */
+	max_count = 32;
+	do {
+		unsigned int iestat, c, cstat;
+		char flag;
+
+		/* get overrun/fifo empty information from ier
+		 * register */
+		iestat = bcm_uart_readl(port, UART_IR_REG);
+
+		if (unlikely(iestat & UART_IR_STAT(UART_IR_RXOVER))) {
+			unsigned int val;
+
+			/* fifo reset is required to clear
+			 * interrupt */
+			val = bcm_uart_readl(port, UART_CTL_REG);
+			val |= UART_CTL_RSTRXFIFO_MASK;
+			bcm_uart_writel(port, val, UART_CTL_REG);
+
+			port->icount.overrun++;
+			tty_insert_flip_char(tty_port, 0, TTY_OVERRUN);
+		}
+
+		if (!(iestat & UART_IR_STAT(UART_IR_RXNOTEMPTY)))
+			break;
+
+		cstat = c = bcm_uart_readl(port, UART_FIFO_REG);
+		port->icount.rx++;
+		flag = TTY_NORMAL;
+		c &= 0xff;
+
+		if (unlikely((cstat & UART_FIFO_ANYERR_MASK))) {
+			/* do stats first */
+			if (cstat & UART_FIFO_BRKDET_MASK) {
+				port->icount.brk++;
+				if (uart_handle_break(port))
+					continue;
+			}
+
+			if (cstat & UART_FIFO_PARERR_MASK)
+				port->icount.parity++;
+			if (cstat & UART_FIFO_FRAMEERR_MASK)
+				port->icount.frame++;
+
+			/* update flag wrt read_status_mask */
+			cstat &= port->read_status_mask;
+			if (cstat & UART_FIFO_BRKDET_MASK)
+				flag = TTY_BREAK;
+			if (cstat & UART_FIFO_FRAMEERR_MASK)
+				flag = TTY_FRAME;
+			if (cstat & UART_FIFO_PARERR_MASK)
+				flag = TTY_PARITY;
+		}
+
+		if (uart_handle_sysrq_char(port, c))
+			continue;
+
+
+		if ((cstat & port->ignore_status_mask) == 0)
+			tty_insert_flip_char(tty_port, c, flag);
+
+	} while (--max_count);
+
+	tty_flip_buffer_push(tty_port);
+}
+
+/*
+ * fill tx fifo with chars to send, stop when fifo is about to be full
+ * or when all chars have been sent.
+ */
+static void bcm_uart_do_tx(struct uart_port *port)
+{
+	unsigned int val;
+	bool pending;
+	u8 ch;
+
+	val = bcm_uart_readl(port, UART_MCTL_REG);
+	val = (val & UART_MCTL_TXFIFOFILL_MASK) >> UART_MCTL_TXFIFOFILL_SHIFT;
+
+	pending = uart_port_tx_limited(port, ch, port->fifosize - val,
+		true,
+		bcm_uart_writel(port, ch, UART_FIFO_REG),
+		({}));
+	if (pending)
+		return;
+
+	/* nothing to send, disable transmit interrupt */
+	val = bcm_uart_readl(port, UART_IR_REG);
+	val &= ~UART_TX_INT_MASK;
+	bcm_uart_writel(port, val, UART_IR_REG);
+}
+
+/*
+ * process uart interrupt
+ */
+static irqreturn_t bcm_uart_interrupt(int irq, void *dev_id)
+{
+	struct uart_port *port;
+	unsigned int irqstat;
+
+	port = dev_id;
+	spin_lock(&port->lock);
+
+	irqstat = bcm_uart_readl(port, UART_IR_REG);
+	if (irqstat & UART_RX_INT_STAT)
+		bcm_uart_do_rx(port);
+
+	if (irqstat & UART_TX_INT_STAT)
+		bcm_uart_do_tx(port);
+
+	if (irqstat & UART_IR_MASK(UART_IR_EXTIP)) {
+		unsigned int estat;
+
+		estat = bcm_uart_readl(port, UART_EXTINP_REG);
+		if (estat & UART_EXTINP_IRSTAT(UART_EXTINP_IR_CTS))
+			uart_handle_cts_change(port,
+					       estat & UART_EXTINP_CTS_MASK);
+		if (estat & UART_EXTINP_IRSTAT(UART_EXTINP_IR_DCD))
+			uart_handle_dcd_change(port,
+					       estat & UART_EXTINP_DCD_MASK);
+	}
+
+	spin_unlock(&port->lock);
+	return IRQ_HANDLED;
+}
+
+/*
+ * enable rx & tx operation on uart
+ */
+static void bcm_uart_enable(struct uart_port *port)
+{
+	unsigned int val;
+
+	val = bcm_uart_readl(port, UART_CTL_REG);
+	val |= (UART_CTL_BRGEN_MASK | UART_CTL_TXEN_MASK | UART_CTL_RXEN_MASK);
+	bcm_uart_writel(port, val, UART_CTL_REG);
+}
+
+/*
+ * disable rx & tx operation on uart
+ */
+static void bcm_uart_disable(struct uart_port *port)
+{
+	unsigned int val;
+
+	val = bcm_uart_readl(port, UART_CTL_REG);
+	val &= ~(UART_CTL_BRGEN_MASK | UART_CTL_TXEN_MASK |
+		 UART_CTL_RXEN_MASK);
+	bcm_uart_writel(port, val, UART_CTL_REG);
+}
+
+/*
+ * clear all unread data in rx fifo and unsent data in tx fifo
+ */
+static void bcm_uart_flush(struct uart_port *port)
+{
+	unsigned int val;
+
+	/* empty rx and tx fifo */
+	val = bcm_uart_readl(port, UART_CTL_REG);
+	val |= UART_CTL_RSTRXFIFO_MASK | UART_CTL_RSTTXFIFO_MASK;
+	bcm_uart_writel(port, val, UART_CTL_REG);
+
+	/* read any pending char to make sure all irq status are
+	 * cleared */
+	(void)bcm_uart_readl(port, UART_FIFO_REG);
+}
+
+/*
+ * serial core request to initialize uart and start rx operation
+ */
+static int bcm_uart_startup(struct uart_port *port)
+{
+	unsigned int val;
+	int ret;
+
+	/* mask all irq and flush port */
+	bcm_uart_disable(port);
+	bcm_uart_writel(port, 0, UART_IR_REG);
+	bcm_uart_flush(port);
+
+	/* clear any pending external input interrupt */
+	(void)bcm_uart_readl(port, UART_EXTINP_REG);
+
+	/* set rx/tx fifo thresh to fifo half size */
+	val = bcm_uart_readl(port, UART_MCTL_REG);
+	val &= ~(UART_MCTL_RXFIFOTHRESH_MASK | UART_MCTL_TXFIFOTHRESH_MASK);
+	val |= (port->fifosize / 2) << UART_MCTL_RXFIFOTHRESH_SHIFT;
+	val |= (port->fifosize / 2) << UART_MCTL_TXFIFOTHRESH_SHIFT;
+	bcm_uart_writel(port, val, UART_MCTL_REG);
+
+	/* set rx fifo timeout to 1 char time */
+	val = bcm_uart_readl(port, UART_CTL_REG);
+	val &= ~UART_CTL_RXTMOUTCNT_MASK;
+	val |= 1 << UART_CTL_RXTMOUTCNT_SHIFT;
+	bcm_uart_writel(port, val, UART_CTL_REG);
+
+	/* report any edge on dcd and cts */
+	val = UART_EXTINP_INT_MASK;
+	val |= UART_EXTINP_DCD_NOSENSE_MASK;
+	val |= UART_EXTINP_CTS_NOSENSE_MASK;
+	bcm_uart_writel(port, val, UART_EXTINP_REG);
+
+	/* register irq and enable rx interrupts */
+	ret = request_irq(port->irq, bcm_uart_interrupt, 0,
+			  dev_name(port->dev), port);
+	if (ret)
+		return ret;
+	bcm_uart_writel(port, UART_RX_INT_MASK, UART_IR_REG);
+	bcm_uart_enable(port);
+	return 0;
+}
+
+/*
+ * serial core request to flush & disable uart
+ */
+static void bcm_uart_shutdown(struct uart_port *port)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&port->lock, flags);
+	bcm_uart_writel(port, 0, UART_IR_REG);
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	bcm_uart_disable(port);
+	bcm_uart_flush(port);
+	free_irq(port->irq, port);
+}
+
+/*
+ * serial core request to change current uart setting
+ */
+static void bcm_uart_set_termios(struct uart_port *port, struct ktermios *new,
+				 const struct ktermios *old)
+{
+	unsigned int ctl, baud, quot, ier;
+	unsigned long flags;
+	int tries;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	/* Drain the hot tub fully before we power it off for the winter. */
+	for (tries = 3; !bcm_uart_tx_empty(port) && tries; tries--)
+		mdelay(10);
+
+	/* disable uart while changing speed */
+	bcm_uart_disable(port);
+	bcm_uart_flush(port);
+
+	/* update Control register */
+	ctl = bcm_uart_readl(port, UART_CTL_REG);
+	ctl &= ~UART_CTL_BITSPERSYM_MASK;
+
+	switch (new->c_cflag & CSIZE) {
+	case CS5:
+		ctl |= (0 << UART_CTL_BITSPERSYM_SHIFT);
+		break;
+	case CS6:
+		ctl |= (1 << UART_CTL_BITSPERSYM_SHIFT);
+		break;
+	case CS7:
+		ctl |= (2 << UART_CTL_BITSPERSYM_SHIFT);
+		break;
+	default:
+		ctl |= (3 << UART_CTL_BITSPERSYM_SHIFT);
+		break;
+	}
+
+	ctl &= ~UART_CTL_STOPBITS_MASK;
+	if (new->c_cflag & CSTOPB)
+		ctl |= UART_CTL_STOPBITS_2;
+	else
+		ctl |= UART_CTL_STOPBITS_1;
+
+	ctl &= ~(UART_CTL_RXPAREN_MASK | UART_CTL_TXPAREN_MASK);
+	if (new->c_cflag & PARENB)
+		ctl |= (UART_CTL_RXPAREN_MASK | UART_CTL_TXPAREN_MASK);
+	ctl &= ~(UART_CTL_RXPAREVEN_MASK | UART_CTL_TXPAREVEN_MASK);
+	if (new->c_cflag & PARODD)
+		ctl |= (UART_CTL_RXPAREVEN_MASK | UART_CTL_TXPAREVEN_MASK);
+	bcm_uart_writel(port, ctl, UART_CTL_REG);
+
+	/* update Baudword register */
+	baud = uart_get_baud_rate(port, new, old, 0, port->uartclk / 16);
+	quot = uart_get_divisor(port, baud) - 1;
+	bcm_uart_writel(port, quot, UART_BAUD_REG);
+
+	/* update Interrupt register */
+	ier = bcm_uart_readl(port, UART_IR_REG);
+
+	ier &= ~UART_IR_MASK(UART_IR_EXTIP);
+	if (UART_ENABLE_MS(port, new->c_cflag))
+		ier |= UART_IR_MASK(UART_IR_EXTIP);
+
+	bcm_uart_writel(port, ier, UART_IR_REG);
+
+	/* update read/ignore mask */
+	port->read_status_mask = UART_FIFO_VALID_MASK;
+	if (new->c_iflag & INPCK) {
+		port->read_status_mask |= UART_FIFO_FRAMEERR_MASK;
+		port->read_status_mask |= UART_FIFO_PARERR_MASK;
+	}
+	if (new->c_iflag & (IGNBRK | BRKINT))
+		port->read_status_mask |= UART_FIFO_BRKDET_MASK;
+
+	port->ignore_status_mask = 0;
+	if (new->c_iflag & IGNPAR)
+		port->ignore_status_mask |= UART_FIFO_PARERR_MASK;
+	if (new->c_iflag & IGNBRK)
+		port->ignore_status_mask |= UART_FIFO_BRKDET_MASK;
+	if (!(new->c_cflag & CREAD))
+		port->ignore_status_mask |= UART_FIFO_VALID_MASK;
+
+	uart_update_timeout(port, new->c_cflag, baud);
+	bcm_uart_enable(port);
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+/*
+ * serial core request to claim uart iomem
+ */
+static int bcm_uart_request_port(struct uart_port *port)
+{
+	/* UARTs always present */
+	return 0;
+}
+
+/*
+ * serial core request to release uart iomem
+ */
+static void bcm_uart_release_port(struct uart_port *port)
+{
+	/* Nothing to release ... */
+}
+
+/*
+ * serial core request to do any port required autoconfiguration
+ */
+static void bcm_uart_config_port(struct uart_port *port, int flags)
+{
+	if (flags & UART_CONFIG_TYPE) {
+		if (bcm_uart_request_port(port))
+			return;
+		port->type = PORT_BCM63XX;
+	}
+}
+
+/*
+ * serial core request to check that port information in serinfo are
+ * suitable
+ */
+static int bcm_uart_verify_port(struct uart_port *port,
+				struct serial_struct *serinfo)
+{
+	if (port->type != PORT_BCM63XX)
+		return -EINVAL;
+	if (port->irq != serinfo->irq)
+		return -EINVAL;
+	if (port->iotype != serinfo->io_type)
+		return -EINVAL;
+	if (port->mapbase != (unsigned long)serinfo->iomem_base)
+		return -EINVAL;
+	return 0;
+}
+
+#ifdef CONFIG_CONSOLE_POLL
+/*
+ * return true when outstanding tx equals fifo size
+ */
+static bool bcm_uart_tx_full(struct uart_port *port)
+{
+	unsigned int val;
+
+	val = bcm_uart_readl(port, UART_MCTL_REG);
+	val = (val & UART_MCTL_TXFIFOFILL_MASK) >> UART_MCTL_TXFIFOFILL_SHIFT;
+	return !(port->fifosize - val);
+}
+
+static int bcm_uart_poll_get_char(struct uart_port *port)
+{
+	unsigned int iestat;
+
+	iestat = bcm_uart_readl(port, UART_IR_REG);
+	if (!(iestat & UART_IR_STAT(UART_IR_RXNOTEMPTY)))
+		return NO_POLL_CHAR;
+
+	return bcm_uart_readl(port, UART_FIFO_REG);
+}
+
+static void bcm_uart_poll_put_char(struct uart_port *port, unsigned char c)
+{
+	while (bcm_uart_tx_full(port)) {
+		cpu_relax();
+	}
+
+	bcm_uart_writel(port, c, UART_FIFO_REG);
+}
+#endif
+
+/* serial core callbacks */
+static const struct uart_ops bcm_uart_ops = {
+	.tx_empty	= bcm_uart_tx_empty,
+	.get_mctrl	= bcm_uart_get_mctrl,
+	.set_mctrl	= bcm_uart_set_mctrl,
+	.start_tx	= bcm_uart_start_tx,
+	.stop_tx	= bcm_uart_stop_tx,
+	.stop_rx	= bcm_uart_stop_rx,
+	.enable_ms	= bcm_uart_enable_ms,
+	.break_ctl	= bcm_uart_break_ctl,
+	.startup	= bcm_uart_startup,
+	.shutdown	= bcm_uart_shutdown,
+	.set_termios	= bcm_uart_set_termios,
+	.type		= bcm_uart_type,
+	.release_port	= bcm_uart_release_port,
+	.request_port	= bcm_uart_request_port,
+	.config_port	= bcm_uart_config_port,
+	.verify_port	= bcm_uart_verify_port,
+#ifdef CONFIG_CONSOLE_POLL
+	.poll_get_char  = bcm_uart_poll_get_char,
+	.poll_put_char  = bcm_uart_poll_put_char,
+#endif
+};
+
+
+
+#ifdef CONFIG_SERIAL_BCM63XX_CONSOLE
+static void wait_for_xmitr(struct uart_port *port)
+{
+	unsigned int tmout;
+
+	/* Wait up to 10ms for the character(s) to be sent. */
+	tmout = 10000;
+	while (--tmout) {
+		unsigned int val;
+
+		val = bcm_uart_readl(port, UART_IR_REG);
+		if (val & UART_IR_STAT(UART_IR_TXEMPTY))
+			break;
+		udelay(1);
+	}
+
+	/* Wait up to 1s for flow control if necessary */
+	if (port->flags & UPF_CONS_FLOW) {
+		tmout = 1000000;
+		while (--tmout) {
+			unsigned int val;
+
+			val = bcm_uart_readl(port, UART_EXTINP_REG);
+			if (val & UART_EXTINP_CTS_MASK)
+				break;
+			udelay(1);
+		}
+	}
+}
+
+/*
+ * output given char
+ */
+static void bcm_console_putchar(struct uart_port *port, unsigned char ch)
+{
+	wait_for_xmitr(port);
+	bcm_uart_writel(port, ch, UART_FIFO_REG);
+}
+
+/*
+ * console core request to output given string
+ */
+static void bcm_console_write(struct console *co, const char *s,
+			      unsigned int count)
+{
+	struct uart_port *port;
+	unsigned long flags;
+	int locked;
+
+	port = &ports[co->index];
+
+	local_irq_save(flags);
+	if (port->sysrq) {
+		/* bcm_uart_interrupt() already took the lock */
+		locked = 0;
+	} else if (oops_in_progress) {
+		locked = spin_trylock(&port->lock);
+	} else {
+		spin_lock(&port->lock);
+		locked = 1;
+	}
+
+	/* call helper to deal with \r\n */
+	uart_console_write(port, s, count, bcm_console_putchar);
+
+	/* and wait for char to be transmitted */
+	wait_for_xmitr(port);
+
+	if (locked)
+		spin_unlock(&port->lock);
+	local_irq_restore(flags);
+}
+
+/*
+ * console core request to setup given console, find matching uart
+ * port and setup it.
+ */
+static int bcm_console_setup(struct console *co, char *options)
+{
+	struct uart_port *port;
+	int baud = 9600;
+	int bits = 8;
+	int parity = 'n';
+	int flow = 'n';
+
+	if (co->index < 0 || co->index >= BCM63XX_NR_UARTS)
+		return -EINVAL;
+	port = &ports[co->index];
+	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 uart_driver bcm_uart_driver;
+
+static struct console bcm63xx_console = {
+	.name		= "ttyS",
+	.write		= bcm_console_write,
+	.device		= uart_console_device,
+	.setup		= bcm_console_setup,
+	.flags		= CON_PRINTBUFFER,
+	.index		= -1,
+	.data		= &bcm_uart_driver,
+};
+
+static int __init bcm63xx_console_init(void)
+{
+	register_console(&bcm63xx_console);
+	return 0;
+}
+
+console_initcall(bcm63xx_console_init);
+
+static void bcm_early_write(struct console *con, const char *s, unsigned n)
+{
+	struct earlycon_device *dev = con->data;
+
+	uart_console_write(&dev->port, s, n, bcm_console_putchar);
+	wait_for_xmitr(&dev->port);
+}
+
+static int __init bcm_early_console_setup(struct earlycon_device *device,
+					  const char *opt)
+{
+	if (!device->port.membase)
+		return -ENODEV;
+
+	device->con->write = bcm_early_write;
+	return 0;
+}
+
+OF_EARLYCON_DECLARE(bcm63xx_uart, "brcm,bcm6345-uart", bcm_early_console_setup);
+
+#define BCM63XX_CONSOLE	(&bcm63xx_console)
+#else
+#define BCM63XX_CONSOLE	NULL
+#endif /* CONFIG_SERIAL_BCM63XX_CONSOLE */
+
+static struct uart_driver bcm_uart_driver = {
+	.owner		= THIS_MODULE,
+	.driver_name	= "bcm63xx_uart",
+	.dev_name	= "ttyS",
+	.major		= TTY_MAJOR,
+	.minor		= 64,
+	.nr		= BCM63XX_NR_UARTS,
+	.cons		= BCM63XX_CONSOLE,
+};
+
+/*
+ * platform driver probe/remove callback
+ */
+static int bcm_uart_probe(struct platform_device *pdev)
+{
+	struct resource *res_mem;
+	struct uart_port *port;
+	struct clk *clk;
+	int ret;
+
+	if (pdev->dev.of_node) {
+		pdev->id = of_alias_get_id(pdev->dev.of_node, "serial");
+
+		if (pdev->id < 0)
+			pdev->id = of_alias_get_id(pdev->dev.of_node, "uart");
+	}
+
+	if (pdev->id < 0 || pdev->id >= BCM63XX_NR_UARTS)
+		return -EINVAL;
+
+	port = &ports[pdev->id];
+	if (port->membase)
+		return -EBUSY;
+	memset(port, 0, sizeof(*port));
+
+	port->membase = devm_platform_get_and_ioremap_resource(pdev, 0, &res_mem);
+	if (IS_ERR(port->membase))
+		return PTR_ERR(port->membase);
+	port->mapbase = res_mem->start;
+
+	ret = platform_get_irq(pdev, 0);
+	if (ret < 0)
+		return ret;
+	port->irq = ret;
+
+	clk = clk_get(&pdev->dev, "refclk");
+	if (IS_ERR(clk) && pdev->dev.of_node)
+		clk = of_clk_get(pdev->dev.of_node, 0);
+
+	if (IS_ERR(clk))
+		return -ENODEV;
+
+	port->iotype = UPIO_MEM;
+	port->ops = &bcm_uart_ops;
+	port->flags = UPF_BOOT_AUTOCONF;
+	port->dev = &pdev->dev;
+	port->fifosize = 16;
+	port->uartclk = clk_get_rate(clk) / 2;
+	port->line = pdev->id;
+	port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_BCM63XX_CONSOLE);
+	clk_put(clk);
+
+	ret = uart_add_one_port(&bcm_uart_driver, port);
+	if (ret) {
+		ports[pdev->id].membase = NULL;
+		return ret;
+	}
+	platform_set_drvdata(pdev, port);
+	return 0;
+}
+
+static int bcm_uart_remove(struct platform_device *pdev)
+{
+	struct uart_port *port;
+
+	port = platform_get_drvdata(pdev);
+	uart_remove_one_port(&bcm_uart_driver, port);
+	/* mark port as free */
+	ports[pdev->id].membase = NULL;
+	return 0;
+}
+
+static const struct of_device_id bcm63xx_of_match[] = {
+	{ .compatible = "brcm,bcm6345-uart" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, bcm63xx_of_match);
+
+/*
+ * platform driver stuff
+ */
+static struct platform_driver bcm_uart_platform_driver = {
+	.probe	= bcm_uart_probe,
+	.remove	= bcm_uart_remove,
+	.driver	= {
+		.name  = "bcm63xx_uart",
+		.of_match_table = bcm63xx_of_match,
+	},
+};
+
+static int __init bcm_uart_init(void)
+{
+	int ret;
+
+	ret = uart_register_driver(&bcm_uart_driver);
+	if (ret)
+		return ret;
+
+	ret = platform_driver_register(&bcm_uart_platform_driver);
+	if (ret)
+		uart_unregister_driver(&bcm_uart_driver);
+
+	return ret;
+}
+
+static void __exit bcm_uart_exit(void)
+{
+	platform_driver_unregister(&bcm_uart_platform_driver);
+	uart_unregister_driver(&bcm_uart_driver);
+}
+
+module_init(bcm_uart_init);
+module_exit(bcm_uart_exit);
+
+MODULE_AUTHOR("Maxime Bizon <mbizon@freebox.fr>");
+MODULE_DESCRIPTION("Broadcom 63xx integrated uart driver");
+MODULE_LICENSE("GPL");