diff options
Diffstat (limited to 'drivers/tty/serial/mvebu-uart.c')
| -rw-r--r-- | drivers/tty/serial/mvebu-uart.c | 995 |
1 files changed, 995 insertions, 0 deletions
diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c new file mode 100644 index 000000000..77f3f3728 --- /dev/null +++ b/drivers/tty/serial/mvebu-uart.c @@ -0,0 +1,995 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* +* *************************************************************************** +* Marvell Armada-3700 Serial Driver +* Author: Wilson Ding <dingwei@marvell.com> +* Copyright (C) 2015 Marvell International Ltd. +* *************************************************************************** +*/ + +#include <linux/clk.h> +#include <linux/console.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/serial.h> +#include <linux/serial_core.h> +#include <linux/slab.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> + +/* Register Map */ +#define UART_STD_RBR 0x00 +#define UART_EXT_RBR 0x18 + +#define UART_STD_TSH 0x04 +#define UART_EXT_TSH 0x1C + +#define UART_STD_CTRL1 0x08 +#define UART_EXT_CTRL1 0x04 +#define CTRL_SOFT_RST BIT(31) +#define CTRL_TXFIFO_RST BIT(15) +#define CTRL_RXFIFO_RST BIT(14) +#define CTRL_SND_BRK_SEQ BIT(11) +#define CTRL_BRK_DET_INT BIT(3) +#define CTRL_FRM_ERR_INT BIT(2) +#define CTRL_PAR_ERR_INT BIT(1) +#define CTRL_OVR_ERR_INT BIT(0) +#define CTRL_BRK_INT (CTRL_BRK_DET_INT | CTRL_FRM_ERR_INT | \ + CTRL_PAR_ERR_INT | CTRL_OVR_ERR_INT) + +#define UART_STD_CTRL2 UART_STD_CTRL1 +#define UART_EXT_CTRL2 0x20 +#define CTRL_STD_TX_RDY_INT BIT(5) +#define CTRL_EXT_TX_RDY_INT BIT(6) +#define CTRL_STD_RX_RDY_INT BIT(4) +#define CTRL_EXT_RX_RDY_INT BIT(5) + +#define UART_STAT 0x0C +#define STAT_TX_FIFO_EMP BIT(13) +#define STAT_TX_FIFO_FUL BIT(11) +#define STAT_TX_EMP BIT(6) +#define STAT_STD_TX_RDY BIT(5) +#define STAT_EXT_TX_RDY BIT(15) +#define STAT_STD_RX_RDY BIT(4) +#define STAT_EXT_RX_RDY BIT(14) +#define STAT_BRK_DET BIT(3) +#define STAT_FRM_ERR BIT(2) +#define STAT_PAR_ERR BIT(1) +#define STAT_OVR_ERR BIT(0) +#define STAT_BRK_ERR (STAT_BRK_DET | STAT_FRM_ERR \ + | STAT_PAR_ERR | STAT_OVR_ERR) + +#define UART_BRDV 0x10 +#define BRDV_BAUD_MASK 0x3FF + +#define UART_OSAMP 0x14 +#define OSAMP_DEFAULT_DIVISOR 16 + +#define MVEBU_NR_UARTS 2 + +#define MVEBU_UART_TYPE "mvebu-uart" +#define DRIVER_NAME "mvebu_serial" + +enum { + /* Either there is only one summed IRQ... */ + UART_IRQ_SUM = 0, + /* ...or there are two separate IRQ for RX and TX */ + UART_RX_IRQ = 0, + UART_TX_IRQ, + UART_IRQ_COUNT +}; + +/* Diverging register offsets */ +struct uart_regs_layout { + unsigned int rbr; + unsigned int tsh; + unsigned int ctrl; + unsigned int intr; +}; + +/* Diverging flags */ +struct uart_flags { + unsigned int ctrl_tx_rdy_int; + unsigned int ctrl_rx_rdy_int; + unsigned int stat_tx_rdy; + unsigned int stat_rx_rdy; +}; + +/* Driver data, a structure for each UART port */ +struct mvebu_uart_driver_data { + bool is_ext; + struct uart_regs_layout regs; + struct uart_flags flags; +}; + +/* Saved registers during suspend */ +struct mvebu_uart_pm_regs { + unsigned int rbr; + unsigned int tsh; + unsigned int ctrl; + unsigned int intr; + unsigned int stat; + unsigned int brdv; + unsigned int osamp; +}; + +/* MVEBU UART driver structure */ +struct mvebu_uart { + struct uart_port *port; + struct clk *clk; + int irq[UART_IRQ_COUNT]; + unsigned char __iomem *nb; + struct mvebu_uart_driver_data *data; +#if defined(CONFIG_PM) + struct mvebu_uart_pm_regs pm_regs; +#endif /* CONFIG_PM */ +}; + +static struct mvebu_uart *to_mvuart(struct uart_port *port) +{ + return (struct mvebu_uart *)port->private_data; +} + +#define IS_EXTENDED(port) (to_mvuart(port)->data->is_ext) + +#define UART_RBR(port) (to_mvuart(port)->data->regs.rbr) +#define UART_TSH(port) (to_mvuart(port)->data->regs.tsh) +#define UART_CTRL(port) (to_mvuart(port)->data->regs.ctrl) +#define UART_INTR(port) (to_mvuart(port)->data->regs.intr) + +#define CTRL_TX_RDY_INT(port) (to_mvuart(port)->data->flags.ctrl_tx_rdy_int) +#define CTRL_RX_RDY_INT(port) (to_mvuart(port)->data->flags.ctrl_rx_rdy_int) +#define STAT_TX_RDY(port) (to_mvuart(port)->data->flags.stat_tx_rdy) +#define STAT_RX_RDY(port) (to_mvuart(port)->data->flags.stat_rx_rdy) + +static struct uart_port mvebu_uart_ports[MVEBU_NR_UARTS]; + +/* Core UART Driver Operations */ +static unsigned int mvebu_uart_tx_empty(struct uart_port *port) +{ + unsigned long flags; + unsigned int st; + + spin_lock_irqsave(&port->lock, flags); + st = readl(port->membase + UART_STAT); + spin_unlock_irqrestore(&port->lock, flags); + + return (st & STAT_TX_EMP) ? TIOCSER_TEMT : 0; +} + +static unsigned int mvebu_uart_get_mctrl(struct uart_port *port) +{ + return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR; +} + +static void mvebu_uart_set_mctrl(struct uart_port *port, + unsigned int mctrl) +{ +/* + * Even if we do not support configuring the modem control lines, this + * function must be proided to the serial core + */ +} + +static void mvebu_uart_stop_tx(struct uart_port *port) +{ + unsigned int ctl = readl(port->membase + UART_INTR(port)); + + ctl &= ~CTRL_TX_RDY_INT(port); + writel(ctl, port->membase + UART_INTR(port)); +} + +static void mvebu_uart_start_tx(struct uart_port *port) +{ + unsigned int ctl; + struct circ_buf *xmit = &port->state->xmit; + + if (IS_EXTENDED(port) && !uart_circ_empty(xmit)) { + writel(xmit->buf[xmit->tail], port->membase + UART_TSH(port)); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + port->icount.tx++; + } + + ctl = readl(port->membase + UART_INTR(port)); + ctl |= CTRL_TX_RDY_INT(port); + writel(ctl, port->membase + UART_INTR(port)); +} + +static void mvebu_uart_stop_rx(struct uart_port *port) +{ + unsigned int ctl; + + ctl = readl(port->membase + UART_CTRL(port)); + ctl &= ~CTRL_BRK_INT; + writel(ctl, port->membase + UART_CTRL(port)); + + ctl = readl(port->membase + UART_INTR(port)); + ctl &= ~CTRL_RX_RDY_INT(port); + writel(ctl, port->membase + UART_INTR(port)); +} + +static void mvebu_uart_break_ctl(struct uart_port *port, int brk) +{ + unsigned int ctl; + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); + ctl = readl(port->membase + UART_CTRL(port)); + if (brk == -1) + ctl |= CTRL_SND_BRK_SEQ; + else + ctl &= ~CTRL_SND_BRK_SEQ; + writel(ctl, port->membase + UART_CTRL(port)); + spin_unlock_irqrestore(&port->lock, flags); +} + +static void mvebu_uart_rx_chars(struct uart_port *port, unsigned int status) +{ + struct tty_port *tport = &port->state->port; + unsigned char ch = 0; + char flag = 0; + + do { + if (status & STAT_RX_RDY(port)) { + ch = readl(port->membase + UART_RBR(port)); + ch &= 0xff; + flag = TTY_NORMAL; + port->icount.rx++; + + if (status & STAT_PAR_ERR) + port->icount.parity++; + } + + if (status & STAT_BRK_DET) { + port->icount.brk++; + status &= ~(STAT_FRM_ERR | STAT_PAR_ERR); + if (uart_handle_break(port)) + goto ignore_char; + } + + if (status & STAT_OVR_ERR) + port->icount.overrun++; + + if (status & STAT_FRM_ERR) + port->icount.frame++; + + if (uart_handle_sysrq_char(port, ch)) + goto ignore_char; + + if (status & port->ignore_status_mask & STAT_PAR_ERR) + status &= ~STAT_RX_RDY(port); + + status &= port->read_status_mask; + + if (status & STAT_PAR_ERR) + flag = TTY_PARITY; + + status &= ~port->ignore_status_mask; + + if (status & STAT_RX_RDY(port)) + tty_insert_flip_char(tport, ch, flag); + + if (status & STAT_BRK_DET) + tty_insert_flip_char(tport, 0, TTY_BREAK); + + if (status & STAT_FRM_ERR) + tty_insert_flip_char(tport, 0, TTY_FRAME); + + if (status & STAT_OVR_ERR) + tty_insert_flip_char(tport, 0, TTY_OVERRUN); + +ignore_char: + status = readl(port->membase + UART_STAT); + } while (status & (STAT_RX_RDY(port) | STAT_BRK_DET)); + + tty_flip_buffer_push(tport); +} + +static void mvebu_uart_tx_chars(struct uart_port *port, unsigned int status) +{ + struct circ_buf *xmit = &port->state->xmit; + unsigned int count; + unsigned int st; + + if (port->x_char) { + writel(port->x_char, port->membase + UART_TSH(port)); + port->icount.tx++; + port->x_char = 0; + return; + } + + if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { + mvebu_uart_stop_tx(port); + return; + } + + for (count = 0; count < port->fifosize; count++) { + writel(xmit->buf[xmit->tail], port->membase + UART_TSH(port)); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + port->icount.tx++; + + if (uart_circ_empty(xmit)) + break; + + st = readl(port->membase + UART_STAT); + if (st & STAT_TX_FIFO_FUL) + break; + } + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); + + if (uart_circ_empty(xmit)) + mvebu_uart_stop_tx(port); +} + +static irqreturn_t mvebu_uart_isr(int irq, void *dev_id) +{ + struct uart_port *port = (struct uart_port *)dev_id; + unsigned int st = readl(port->membase + UART_STAT); + + if (st & (STAT_RX_RDY(port) | STAT_OVR_ERR | STAT_FRM_ERR | + STAT_BRK_DET)) + mvebu_uart_rx_chars(port, st); + + if (st & STAT_TX_RDY(port)) + mvebu_uart_tx_chars(port, st); + + return IRQ_HANDLED; +} + +static irqreturn_t mvebu_uart_rx_isr(int irq, void *dev_id) +{ + struct uart_port *port = (struct uart_port *)dev_id; + unsigned int st = readl(port->membase + UART_STAT); + + if (st & (STAT_RX_RDY(port) | STAT_OVR_ERR | STAT_FRM_ERR | + STAT_BRK_DET)) + mvebu_uart_rx_chars(port, st); + + return IRQ_HANDLED; +} + +static irqreturn_t mvebu_uart_tx_isr(int irq, void *dev_id) +{ + struct uart_port *port = (struct uart_port *)dev_id; + unsigned int st = readl(port->membase + UART_STAT); + + if (st & STAT_TX_RDY(port)) + mvebu_uart_tx_chars(port, st); + + return IRQ_HANDLED; +} + +static int mvebu_uart_startup(struct uart_port *port) +{ + struct mvebu_uart *mvuart = to_mvuart(port); + unsigned int ctl; + int ret; + + writel(CTRL_TXFIFO_RST | CTRL_RXFIFO_RST, + port->membase + UART_CTRL(port)); + udelay(1); + + /* Clear the error bits of state register before IRQ request */ + ret = readl(port->membase + UART_STAT); + ret |= STAT_BRK_ERR; + writel(ret, port->membase + UART_STAT); + + writel(CTRL_BRK_INT, port->membase + UART_CTRL(port)); + + ctl = readl(port->membase + UART_INTR(port)); + ctl |= CTRL_RX_RDY_INT(port); + writel(ctl, port->membase + UART_INTR(port)); + + if (!mvuart->irq[UART_TX_IRQ]) { + /* Old bindings with just one interrupt (UART0 only) */ + ret = devm_request_irq(port->dev, mvuart->irq[UART_IRQ_SUM], + mvebu_uart_isr, port->irqflags, + dev_name(port->dev), port); + if (ret) { + dev_err(port->dev, "unable to request IRQ %d\n", + mvuart->irq[UART_IRQ_SUM]); + return ret; + } + } else { + /* New bindings with an IRQ for RX and TX (both UART) */ + ret = devm_request_irq(port->dev, mvuart->irq[UART_RX_IRQ], + mvebu_uart_rx_isr, port->irqflags, + dev_name(port->dev), port); + if (ret) { + dev_err(port->dev, "unable to request IRQ %d\n", + mvuart->irq[UART_RX_IRQ]); + return ret; + } + + ret = devm_request_irq(port->dev, mvuart->irq[UART_TX_IRQ], + mvebu_uart_tx_isr, port->irqflags, + dev_name(port->dev), + port); + if (ret) { + dev_err(port->dev, "unable to request IRQ %d\n", + mvuart->irq[UART_TX_IRQ]); + devm_free_irq(port->dev, mvuart->irq[UART_RX_IRQ], + port); + return ret; + } + } + + return 0; +} + +static void mvebu_uart_shutdown(struct uart_port *port) +{ + struct mvebu_uart *mvuart = to_mvuart(port); + + writel(0, port->membase + UART_INTR(port)); + + if (!mvuart->irq[UART_TX_IRQ]) { + devm_free_irq(port->dev, mvuart->irq[UART_IRQ_SUM], port); + } else { + devm_free_irq(port->dev, mvuart->irq[UART_RX_IRQ], port); + devm_free_irq(port->dev, mvuart->irq[UART_TX_IRQ], port); + } +} + +static int mvebu_uart_baud_rate_set(struct uart_port *port, unsigned int baud) +{ + struct mvebu_uart *mvuart = to_mvuart(port); + unsigned int d_divisor, m_divisor; + u32 brdv; + + if (IS_ERR(mvuart->clk)) + return -PTR_ERR(mvuart->clk); + + /* + * The baudrate is derived from the UART clock thanks to two divisors: + * > D ("baud generator"): can divide the clock from 2 to 2^10 - 1. + * > M ("fractional divisor"): allows a better accuracy for + * baudrates higher than 230400. + * + * As the derivation of M is rather complicated, the code sticks to its + * default value (x16) when all the prescalers are zeroed, and only + * makes use of D to configure the desired baudrate. + */ + m_divisor = OSAMP_DEFAULT_DIVISOR; + d_divisor = DIV_ROUND_CLOSEST(port->uartclk, baud * m_divisor); + + brdv = readl(port->membase + UART_BRDV); + brdv &= ~BRDV_BAUD_MASK; + brdv |= d_divisor; + writel(brdv, port->membase + UART_BRDV); + + return 0; +} + +static void mvebu_uart_set_termios(struct uart_port *port, + struct ktermios *termios, + struct ktermios *old) +{ + unsigned long flags; + unsigned int baud, min_baud, max_baud; + + spin_lock_irqsave(&port->lock, flags); + + port->read_status_mask = STAT_RX_RDY(port) | STAT_OVR_ERR | + STAT_TX_RDY(port) | STAT_TX_FIFO_FUL; + + if (termios->c_iflag & INPCK) + port->read_status_mask |= STAT_FRM_ERR | STAT_PAR_ERR; + + port->ignore_status_mask = 0; + if (termios->c_iflag & IGNPAR) + port->ignore_status_mask |= + STAT_FRM_ERR | STAT_PAR_ERR | STAT_OVR_ERR; + + if ((termios->c_cflag & CREAD) == 0) + port->ignore_status_mask |= STAT_RX_RDY(port) | STAT_BRK_ERR; + + /* + * Maximal divisor is 1023 * 16 when using default (x16) scheme. + * Maximum achievable frequency with simple baudrate divisor is 230400. + * Since the error per bit frame would be of more than 15%, achieving + * higher frequencies would require to implement the fractional divisor + * feature. + */ + min_baud = DIV_ROUND_UP(port->uartclk, 1023 * 16); + max_baud = 230400; + + baud = uart_get_baud_rate(port, termios, old, min_baud, max_baud); + if (mvebu_uart_baud_rate_set(port, baud)) { + /* No clock available, baudrate cannot be changed */ + if (old) + baud = uart_get_baud_rate(port, old, NULL, + min_baud, max_baud); + } else { + tty_termios_encode_baud_rate(termios, baud, baud); + uart_update_timeout(port, termios->c_cflag, baud); + } + + /* Only the following flag changes are supported */ + if (old) { + termios->c_iflag &= INPCK | IGNPAR; + termios->c_iflag |= old->c_iflag & ~(INPCK | IGNPAR); + termios->c_cflag &= CREAD | CBAUD; + termios->c_cflag |= old->c_cflag & ~(CREAD | CBAUD); + termios->c_cflag |= CS8; + } + + spin_unlock_irqrestore(&port->lock, flags); +} + +static const char *mvebu_uart_type(struct uart_port *port) +{ + return MVEBU_UART_TYPE; +} + +static void mvebu_uart_release_port(struct uart_port *port) +{ + /* Nothing to do here */ +} + +static int mvebu_uart_request_port(struct uart_port *port) +{ + return 0; +} + +#ifdef CONFIG_CONSOLE_POLL +static int mvebu_uart_get_poll_char(struct uart_port *port) +{ + unsigned int st = readl(port->membase + UART_STAT); + + if (!(st & STAT_RX_RDY(port))) + return NO_POLL_CHAR; + + return readl(port->membase + UART_RBR(port)); +} + +static void mvebu_uart_put_poll_char(struct uart_port *port, unsigned char c) +{ + unsigned int st; + + for (;;) { + st = readl(port->membase + UART_STAT); + + if (!(st & STAT_TX_FIFO_FUL)) + break; + + udelay(1); + } + + writel(c, port->membase + UART_TSH(port)); +} +#endif + +static const struct uart_ops mvebu_uart_ops = { + .tx_empty = mvebu_uart_tx_empty, + .set_mctrl = mvebu_uart_set_mctrl, + .get_mctrl = mvebu_uart_get_mctrl, + .stop_tx = mvebu_uart_stop_tx, + .start_tx = mvebu_uart_start_tx, + .stop_rx = mvebu_uart_stop_rx, + .break_ctl = mvebu_uart_break_ctl, + .startup = mvebu_uart_startup, + .shutdown = mvebu_uart_shutdown, + .set_termios = mvebu_uart_set_termios, + .type = mvebu_uart_type, + .release_port = mvebu_uart_release_port, + .request_port = mvebu_uart_request_port, +#ifdef CONFIG_CONSOLE_POLL + .poll_get_char = mvebu_uart_get_poll_char, + .poll_put_char = mvebu_uart_put_poll_char, +#endif +}; + +/* Console Driver Operations */ + +#ifdef CONFIG_SERIAL_MVEBU_CONSOLE +/* Early Console */ +static void mvebu_uart_putc(struct uart_port *port, int c) +{ + unsigned int st; + + for (;;) { + st = readl(port->membase + UART_STAT); + if (!(st & STAT_TX_FIFO_FUL)) + break; + } + + /* At early stage, DT is not parsed yet, only use UART0 */ + writel(c, port->membase + UART_STD_TSH); + + for (;;) { + st = readl(port->membase + UART_STAT); + if (st & STAT_TX_FIFO_EMP) + break; + } +} + +static void mvebu_uart_putc_early_write(struct console *con, + const char *s, + unsigned n) +{ + struct earlycon_device *dev = con->data; + + uart_console_write(&dev->port, s, n, mvebu_uart_putc); +} + +static int __init +mvebu_uart_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + if (!device->port.membase) + return -ENODEV; + + device->con->write = mvebu_uart_putc_early_write; + + return 0; +} + +EARLYCON_DECLARE(ar3700_uart, mvebu_uart_early_console_setup); +OF_EARLYCON_DECLARE(ar3700_uart, "marvell,armada-3700-uart", + mvebu_uart_early_console_setup); + +static void wait_for_xmitr(struct uart_port *port) +{ + u32 val; + + readl_poll_timeout_atomic(port->membase + UART_STAT, val, + (val & STAT_TX_RDY(port)), 1, 10000); +} + +static void wait_for_xmite(struct uart_port *port) +{ + u32 val; + + readl_poll_timeout_atomic(port->membase + UART_STAT, val, + (val & STAT_TX_EMP), 1, 10000); +} + +static void mvebu_uart_console_putchar(struct uart_port *port, int ch) +{ + wait_for_xmitr(port); + writel(ch, port->membase + UART_TSH(port)); +} + +static void mvebu_uart_console_write(struct console *co, const char *s, + unsigned int count) +{ + struct uart_port *port = &mvebu_uart_ports[co->index]; + unsigned long flags; + unsigned int ier, intr, ctl; + int locked = 1; + + if (oops_in_progress) + locked = spin_trylock_irqsave(&port->lock, flags); + else + spin_lock_irqsave(&port->lock, flags); + + ier = readl(port->membase + UART_CTRL(port)) & CTRL_BRK_INT; + intr = readl(port->membase + UART_INTR(port)) & + (CTRL_RX_RDY_INT(port) | CTRL_TX_RDY_INT(port)); + writel(0, port->membase + UART_CTRL(port)); + writel(0, port->membase + UART_INTR(port)); + + uart_console_write(port, s, count, mvebu_uart_console_putchar); + + wait_for_xmite(port); + + if (ier) + writel(ier, port->membase + UART_CTRL(port)); + + if (intr) { + ctl = intr | readl(port->membase + UART_INTR(port)); + writel(ctl, port->membase + UART_INTR(port)); + } + + if (locked) + spin_unlock_irqrestore(&port->lock, flags); +} + +static int mvebu_uart_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 >= MVEBU_NR_UARTS) + return -EINVAL; + + port = &mvebu_uart_ports[co->index]; + + if (!port->mapbase || !port->membase) { + pr_debug("console on ttyMV%i not present\n", co->index); + 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 mvebu_uart_driver; + +static struct console mvebu_uart_console = { + .name = "ttyMV", + .write = mvebu_uart_console_write, + .device = uart_console_device, + .setup = mvebu_uart_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &mvebu_uart_driver, +}; + +static int __init mvebu_uart_console_init(void) +{ + register_console(&mvebu_uart_console); + return 0; +} + +console_initcall(mvebu_uart_console_init); + + +#endif /* CONFIG_SERIAL_MVEBU_CONSOLE */ + +static struct uart_driver mvebu_uart_driver = { + .owner = THIS_MODULE, + .driver_name = DRIVER_NAME, + .dev_name = "ttyMV", + .nr = MVEBU_NR_UARTS, +#ifdef CONFIG_SERIAL_MVEBU_CONSOLE + .cons = &mvebu_uart_console, +#endif +}; + +#if defined(CONFIG_PM) +static int mvebu_uart_suspend(struct device *dev) +{ + struct mvebu_uart *mvuart = dev_get_drvdata(dev); + struct uart_port *port = mvuart->port; + + uart_suspend_port(&mvebu_uart_driver, port); + + mvuart->pm_regs.rbr = readl(port->membase + UART_RBR(port)); + mvuart->pm_regs.tsh = readl(port->membase + UART_TSH(port)); + mvuart->pm_regs.ctrl = readl(port->membase + UART_CTRL(port)); + mvuart->pm_regs.intr = readl(port->membase + UART_INTR(port)); + mvuart->pm_regs.stat = readl(port->membase + UART_STAT); + mvuart->pm_regs.brdv = readl(port->membase + UART_BRDV); + mvuart->pm_regs.osamp = readl(port->membase + UART_OSAMP); + + device_set_wakeup_enable(dev, true); + + return 0; +} + +static int mvebu_uart_resume(struct device *dev) +{ + struct mvebu_uart *mvuart = dev_get_drvdata(dev); + struct uart_port *port = mvuart->port; + + writel(mvuart->pm_regs.rbr, port->membase + UART_RBR(port)); + writel(mvuart->pm_regs.tsh, port->membase + UART_TSH(port)); + writel(mvuart->pm_regs.ctrl, port->membase + UART_CTRL(port)); + writel(mvuart->pm_regs.intr, port->membase + UART_INTR(port)); + writel(mvuart->pm_regs.stat, port->membase + UART_STAT); + writel(mvuart->pm_regs.brdv, port->membase + UART_BRDV); + writel(mvuart->pm_regs.osamp, port->membase + UART_OSAMP); + + uart_resume_port(&mvebu_uart_driver, port); + + return 0; +} + +static const struct dev_pm_ops mvebu_uart_pm_ops = { + .suspend = mvebu_uart_suspend, + .resume = mvebu_uart_resume, +}; +#endif /* CONFIG_PM */ + +static const struct of_device_id mvebu_uart_of_match[]; + +/* Counter to keep track of each UART port id when not using CONFIG_OF */ +static int uart_num_counter; + +static int mvebu_uart_probe(struct platform_device *pdev) +{ + struct resource *reg = platform_get_resource(pdev, IORESOURCE_MEM, 0); + const struct of_device_id *match = of_match_device(mvebu_uart_of_match, + &pdev->dev); + struct uart_port *port; + struct mvebu_uart *mvuart; + int ret, id, irq; + + if (!reg) { + dev_err(&pdev->dev, "no registers defined\n"); + return -EINVAL; + } + + /* Assume that all UART ports have a DT alias or none has */ + id = of_alias_get_id(pdev->dev.of_node, "serial"); + if (!pdev->dev.of_node || id < 0) + pdev->id = uart_num_counter++; + else + pdev->id = id; + + if (pdev->id >= MVEBU_NR_UARTS) { + dev_err(&pdev->dev, "cannot have more than %d UART ports\n", + MVEBU_NR_UARTS); + return -EINVAL; + } + + port = &mvebu_uart_ports[pdev->id]; + + spin_lock_init(&port->lock); + + port->dev = &pdev->dev; + port->type = PORT_MVEBU; + port->ops = &mvebu_uart_ops; + port->regshift = 0; + + port->fifosize = 32; + port->iotype = UPIO_MEM32; + port->flags = UPF_FIXED_PORT; + port->line = pdev->id; + + /* + * IRQ number is not stored in this structure because we may have two of + * them per port (RX and TX). Instead, use the driver UART structure + * array so called ->irq[]. + */ + port->irq = 0; + port->irqflags = 0; + port->mapbase = reg->start; + + port->membase = devm_ioremap_resource(&pdev->dev, reg); + if (IS_ERR(port->membase)) + return PTR_ERR(port->membase); + + mvuart = devm_kzalloc(&pdev->dev, sizeof(struct mvebu_uart), + GFP_KERNEL); + if (!mvuart) + return -ENOMEM; + + /* Get controller data depending on the compatible string */ + mvuart->data = (struct mvebu_uart_driver_data *)match->data; + mvuart->port = port; + + port->private_data = mvuart; + platform_set_drvdata(pdev, mvuart); + + /* Get fixed clock frequency */ + mvuart->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(mvuart->clk)) { + if (PTR_ERR(mvuart->clk) == -EPROBE_DEFER) + return PTR_ERR(mvuart->clk); + + if (IS_EXTENDED(port)) { + dev_err(&pdev->dev, "unable to get UART clock\n"); + return PTR_ERR(mvuart->clk); + } + } else { + if (!clk_prepare_enable(mvuart->clk)) + port->uartclk = clk_get_rate(mvuart->clk); + } + + /* Manage interrupts */ + if (platform_irq_count(pdev) == 1) { + /* Old bindings: no name on the single unamed UART0 IRQ */ + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "unable to get UART IRQ\n"); + return irq; + } + + mvuart->irq[UART_IRQ_SUM] = irq; + } else { + /* + * New bindings: named interrupts (RX, TX) for both UARTS, + * only make use of uart-rx and uart-tx interrupts, do not use + * uart-sum of UART0 port. + */ + irq = platform_get_irq_byname(pdev, "uart-rx"); + if (irq < 0) { + dev_err(&pdev->dev, "unable to get 'uart-rx' IRQ\n"); + return irq; + } + + mvuart->irq[UART_RX_IRQ] = irq; + + irq = platform_get_irq_byname(pdev, "uart-tx"); + if (irq < 0) { + dev_err(&pdev->dev, "unable to get 'uart-tx' IRQ\n"); + return irq; + } + + mvuart->irq[UART_TX_IRQ] = irq; + } + + /* UART Soft Reset*/ + writel(CTRL_SOFT_RST, port->membase + UART_CTRL(port)); + udelay(1); + writel(0, port->membase + UART_CTRL(port)); + + ret = uart_add_one_port(&mvebu_uart_driver, port); + if (ret) + return ret; + return 0; +} + +static struct mvebu_uart_driver_data uart_std_driver_data = { + .is_ext = false, + .regs.rbr = UART_STD_RBR, + .regs.tsh = UART_STD_TSH, + .regs.ctrl = UART_STD_CTRL1, + .regs.intr = UART_STD_CTRL2, + .flags.ctrl_tx_rdy_int = CTRL_STD_TX_RDY_INT, + .flags.ctrl_rx_rdy_int = CTRL_STD_RX_RDY_INT, + .flags.stat_tx_rdy = STAT_STD_TX_RDY, + .flags.stat_rx_rdy = STAT_STD_RX_RDY, +}; + +static struct mvebu_uart_driver_data uart_ext_driver_data = { + .is_ext = true, + .regs.rbr = UART_EXT_RBR, + .regs.tsh = UART_EXT_TSH, + .regs.ctrl = UART_EXT_CTRL1, + .regs.intr = UART_EXT_CTRL2, + .flags.ctrl_tx_rdy_int = CTRL_EXT_TX_RDY_INT, + .flags.ctrl_rx_rdy_int = CTRL_EXT_RX_RDY_INT, + .flags.stat_tx_rdy = STAT_EXT_TX_RDY, + .flags.stat_rx_rdy = STAT_EXT_RX_RDY, +}; + +/* Match table for of_platform binding */ +static const struct of_device_id mvebu_uart_of_match[] = { + { + .compatible = "marvell,armada-3700-uart", + .data = (void *)&uart_std_driver_data, + }, + { + .compatible = "marvell,armada-3700-uart-ext", + .data = (void *)&uart_ext_driver_data, + }, + {} +}; + +static struct platform_driver mvebu_uart_platform_driver = { + .probe = mvebu_uart_probe, + .driver = { + .name = "mvebu-uart", + .of_match_table = of_match_ptr(mvebu_uart_of_match), + .suppress_bind_attrs = true, +#if defined(CONFIG_PM) + .pm = &mvebu_uart_pm_ops, +#endif /* CONFIG_PM */ + }, +}; + +static int __init mvebu_uart_init(void) +{ + int ret; + + ret = uart_register_driver(&mvebu_uart_driver); + if (ret) + return ret; + + ret = platform_driver_register(&mvebu_uart_platform_driver); + if (ret) + uart_unregister_driver(&mvebu_uart_driver); + + return ret; +} +arch_initcall(mvebu_uart_init); |