forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
986 lines
25 KiB
986 lines
25 KiB
// SPDX-License-Identifier: GPL-2.0+ |
|
/* |
|
* *************************************************************************** |
|
* Marvell Armada-3700 Serial Driver |
|
* Author: Wilson Ding <[email protected]> |
|
* 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 OSAMP_DIVISORS_MASK 0x3F3F3F3F |
|
|
|
#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_FIFO_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, osamp; |
|
|
|
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_UP(port->uartclk, baud * m_divisor); |
|
|
|
brdv = readl(port->membase + UART_BRDV); |
|
brdv &= ~BRDV_BAUD_MASK; |
|
brdv |= d_divisor; |
|
writel(brdv, port->membase + UART_BRDV); |
|
|
|
osamp = readl(port->membase + UART_OSAMP); |
|
osamp &= ~OSAMP_DIVISORS_MASK; |
|
writel(osamp, port->membase + UART_OSAMP); |
|
|
|
return 0; |
|
} |
|
|
|
static void mvebu_uart_set_termios(struct uart_port *port, |
|
struct ktermios *termios, |
|
struct ktermios *old) |
|
{ |
|
unsigned long flags; |
|
unsigned int 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; |
|
|
|
/* |
|
* 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. |
|
*/ |
|
baud = uart_get_baud_rate(port, termios, old, 0, 230400); |
|
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, 0, 230400); |
|
} 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 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) |
|
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) |
|
return irq; |
|
|
|
mvuart->irq[UART_RX_IRQ] = irq; |
|
|
|
irq = platform_get_irq_byname(pdev, "uart-tx"); |
|
if (irq < 0) |
|
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)); |
|
|
|
return uart_add_one_port(&mvebu_uart_driver, port); |
|
} |
|
|
|
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);
|
|
|