Orange Pi5 kernel

// 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);
 
<------>spin_unlock(&port->lock);
<------>tty_flip_buffer_push(tty_port);
<------>spin_lock(&port->lock);
}
 
/*
 * 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)
{
<------>struct circ_buf *xmit;
<------>unsigned int val, max_count;
 
<------>if (port->x_char) {
<------><------>bcm_uart_writel(port, port->x_char, UART_FIFO_REG);
<------><------>port->icount.tx++;
<------><------>port->x_char = 0;
<------><------>return;
<------>}
 
<------>if (uart_tx_stopped(port)) {
<------><------>bcm_uart_stop_tx(port);
<------><------>return;
<------>}
 
<------>xmit = &port->state->xmit;
<------>if (uart_circ_empty(xmit))
<------><------>goto txq_empty;
 
<------>val = bcm_uart_readl(port, UART_MCTL_REG);
<------>val = (val & UART_MCTL_TXFIFOFILL_MASK) >> UART_MCTL_TXFIFOFILL_SHIFT;
<------>max_count = port->fifosize - val;
 
<------>while (max_count--) {
<------><------>unsigned int c;
 
<------><------>c = xmit->buf[xmit->tail];
<------><------>bcm_uart_writel(port, c, UART_FIFO_REG);
<------><------>xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
<------><------>port->icount.tx++;
<------><------>if (uart_circ_empty(xmit))
<------><------><------>break;
<------>}
 
<------>if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
<------><------>uart_write_wakeup(port);
 
<------>if (uart_circ_empty(xmit))
<------><------>goto txq_empty;
<------>return;
 
txq_empty:
<------>/* 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);
<------>return;
}
 
/*
 * 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,
<------><------><------><------> 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;
}
 
/* 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_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, int 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, *res_irq;
<------>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));
 
<------>res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
<------>if (!res_mem)
<------><------>return -ENODEV;
 
<------>port->mapbase = res_mem->start;
<------>port->membase = devm_ioremap_resource(&pdev->dev, res_mem);
<------>if (IS_ERR(port->membase))
<------><------>return PTR_ERR(port->membase);
 
<------>res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
<------>if (!res_irq)
<------><------>return -ENODEV;
 
<------>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->irq = res_irq->start;
<------>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");