diff options
Diffstat (limited to 'drivers/tty/serial/imx.c')
| -rw-r--r-- | drivers/tty/serial/imx.c | 250 |
1 files changed, 197 insertions, 53 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index ff32cd2d2863..c488e5d372ff 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -30,7 +30,7 @@ #include <linux/iopoll.h> #include <linux/dma-mapping.h> -#include <asm/irq.h> +#include <linux/irq.h> #include <linux/dma/imx-dma.h> #include "serial_mctrl_gpio.h" @@ -230,9 +230,12 @@ struct imx_port { unsigned int saved_reg[10]; bool context_saved; + bool last_putchar_was_newline; + enum imx_tx_state tx_state; struct hrtimer trigger_start_tx; struct hrtimer trigger_stop_tx; + unsigned int rxtl; }; struct imx_port_ucrs { @@ -265,6 +268,11 @@ static const struct of_device_id imx_uart_dt_ids[] = { }; MODULE_DEVICE_TABLE(of, imx_uart_dt_ids); +static inline struct imx_port *to_imx_port(struct uart_port *port) +{ + return container_of(port, struct imx_port, port); +} + static inline void imx_uart_writel(struct imx_port *sport, u32 val, u32 offset) { writel(val, sport->port.membase + offset); @@ -365,6 +373,7 @@ static void imx_uart_soft_reset(struct imx_port *sport) sport->idle_counter = 0; } +/* called with port.lock taken and irqs off */ static void imx_uart_disable_loopback_rs485(struct imx_port *sport) { unsigned int uts; @@ -378,7 +387,7 @@ static void imx_uart_disable_loopback_rs485(struct imx_port *sport) /* called with port.lock taken and irqs off */ static void imx_uart_start_rx(struct uart_port *port) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); unsigned int ucr1, ucr2; ucr1 = imx_uart_readl(sport, UCR1); @@ -402,7 +411,7 @@ static void imx_uart_start_rx(struct uart_port *port) /* called with port.lock taken and irqs off */ static void imx_uart_stop_tx(struct uart_port *port) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); u32 ucr1, ucr4, usr2; if (sport->tx_state == OFF) @@ -465,9 +474,10 @@ static void imx_uart_stop_tx(struct uart_port *port) } } +/* called with port.lock taken and irqs off */ static void imx_uart_stop_rx_with_loopback_ctrl(struct uart_port *port, bool loopback) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); u32 ucr1, ucr2, ucr4, uts; ucr1 = imx_uart_readl(sport, UCR1); @@ -512,7 +522,7 @@ static void imx_uart_stop_rx(struct uart_port *port) /* called with port.lock taken and irqs off */ static void imx_uart_enable_ms(struct uart_port *port) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); mod_timer(&sport->timer, jiffies); @@ -663,7 +673,7 @@ static void imx_uart_dma_tx(struct imx_port *sport) /* called with port.lock taken and irqs off */ static void imx_uart_start_tx(struct uart_port *port) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); struct tty_port *tport = &sport->port.state->port; u32 ucr1; @@ -757,6 +767,21 @@ static irqreturn_t __imx_uart_rtsint(int irq, void *dev_id) imx_uart_writel(sport, USR1_RTSD, USR1); usr1 = imx_uart_readl(sport, USR1) & USR1_RTSS; + /* + * Update sport->old_status here, so any follow-up calls to + * imx_uart_mctrl_check() will be able to recognize that RTS + * state changed since last imx_uart_mctrl_check() call. + * + * In case RTS has been detected as asserted here and later on + * deasserted by the time imx_uart_mctrl_check() was called, + * imx_uart_mctrl_check() can detect the RTS state change and + * trigger uart_handle_cts_change() to unblock the port for + * further TX transfers. + */ + if (usr1 & USR1_RTSS) + sport->old_status |= TIOCM_CTS; + else + sport->old_status &= ~TIOCM_CTS; uart_handle_cts_change(&sport->port, usr1); wake_up_interruptible(&sport->port.state->port.delta_msr_wait); @@ -798,6 +823,8 @@ static irqreturn_t imx_uart_txint(int irq, void *dev_id) * issuing soft reset to the UART (just stop/start of RX does not help). Note * that what we do here is sending isolated start bit about 2.4 times shorter * than it is to be on UART configured baud rate. + * + * Called with port.lock taken and irqs off. */ static void imx_uart_check_flood(struct imx_port *sport, u32 usr2) { @@ -833,6 +860,7 @@ static void imx_uart_check_flood(struct imx_port *sport, u32 usr2) } } +/* called with port.lock taken and irqs off */ static irqreturn_t __imx_uart_rxint(int irq, void *dev_id) { struct imx_port *sport = dev_id; @@ -911,6 +939,7 @@ static void imx_uart_clear_rx_errors(struct imx_port *sport); /* * We have a modem side uart, so the meanings of RTS and CTS are inverted. */ +/* called with port.lock taken and irqs off */ static unsigned int imx_uart_get_hwmctrl(struct imx_port *sport) { unsigned int tmp = TIOCM_DSR; @@ -933,6 +962,8 @@ static unsigned int imx_uart_get_hwmctrl(struct imx_port *sport) /* * Handle any change of modem status signal since we were last called. + * + * Called with port.lock taken and irqs off. */ static void imx_uart_mctrl_check(struct imx_port *sport) { @@ -1044,7 +1075,7 @@ static irqreturn_t imx_uart_int(int irq, void *dev_id) */ static unsigned int imx_uart_tx_empty(struct uart_port *port) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); unsigned int ret; ret = (imx_uart_readl(sport, USR2) & USR2_TXDC) ? TIOCSER_TEMT : 0; @@ -1059,7 +1090,7 @@ static unsigned int imx_uart_tx_empty(struct uart_port *port) /* called with port.lock taken and irqs off */ static unsigned int imx_uart_get_mctrl(struct uart_port *port) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); unsigned int ret = imx_uart_get_hwmctrl(sport); mctrl_gpio_get(sport->gpios, &ret); @@ -1070,7 +1101,7 @@ static unsigned int imx_uart_get_mctrl(struct uart_port *port) /* called with port.lock taken and irqs off */ static void imx_uart_set_mctrl(struct uart_port *port, unsigned int mctrl) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); u32 ucr3, uts; if (!(port->rs485.flags & SER_RS485_ENABLED)) { @@ -1113,7 +1144,7 @@ static void imx_uart_set_mctrl(struct uart_port *port, unsigned int mctrl) */ static void imx_uart_break_ctl(struct uart_port *port, int break_state) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); unsigned long flags; u32 ucr1; @@ -1135,7 +1166,7 @@ static void imx_uart_break_ctl(struct uart_port *port, int break_state) */ static void imx_uart_timeout(struct timer_list *t) { - struct imx_port *sport = from_timer(sport, t, timer); + struct imx_port *sport = timer_container_of(sport, t, timer); unsigned long flags; if (sport->port.state) { @@ -1272,6 +1303,7 @@ static int imx_uart_start_rx_dma(struct imx_port *sport) return 0; } +/* called with port.lock taken and irqs off */ static void imx_uart_clear_rx_errors(struct imx_port *sport) { struct tty_port *port = &sport->port.state->port; @@ -1308,6 +1340,7 @@ static void imx_uart_clear_rx_errors(struct imx_port *sport) #define TXTL_DEFAULT 8 #define RXTL_DEFAULT 8 /* 8 characters or aging timer */ +#define RXTL_CONSOLE_DEFAULT 1 #define TXTL_DMA 8 /* DMA burst setting */ #define RXTL_DMA 9 /* DMA burst setting */ @@ -1402,6 +1435,7 @@ err: return ret; } +/* called with port.lock taken and irqs off */ static void imx_uart_enable_dma(struct imx_port *sport) { u32 ucr1; @@ -1425,7 +1459,7 @@ static void imx_uart_disable_dma(struct imx_port *sport) ucr1 &= ~(UCR1_RXDMAEN | UCR1_TXDMAEN | UCR1_ATDMAEN); imx_uart_writel(sport, ucr1, UCR1); - imx_uart_setup_ufcr(sport, TXTL_DEFAULT, RXTL_DEFAULT); + imx_uart_setup_ufcr(sport, TXTL_DEFAULT, sport->rxtl); sport->dma_is_enabled = 0; } @@ -1435,7 +1469,7 @@ static void imx_uart_disable_dma(struct imx_port *sport) static int imx_uart_startup(struct uart_port *port) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); int retval; unsigned long flags; int dma_is_inited = 0; @@ -1450,7 +1484,12 @@ static int imx_uart_startup(struct uart_port *port) return retval; } - imx_uart_setup_ufcr(sport, TXTL_DEFAULT, RXTL_DEFAULT); + if (uart_console(&sport->port)) + sport->rxtl = RXTL_CONSOLE_DEFAULT; + else + sport->rxtl = RXTL_DEFAULT; + + imx_uart_setup_ufcr(sport, TXTL_DEFAULT, sport->rxtl); /* disable the DREN bit (Data Ready interrupt enable) before * requesting IRQs @@ -1549,7 +1588,7 @@ static int imx_uart_startup(struct uart_port *port) static void imx_uart_shutdown(struct uart_port *port) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); unsigned long flags; u32 ucr1, ucr2, ucr4, uts; int loops; @@ -1576,7 +1615,7 @@ static void imx_uart_shutdown(struct uart_port *port) imx_uart_dma_exit(sport); } - mctrl_gpio_disable_ms(sport->gpios); + mctrl_gpio_disable_ms_sync(sport->gpios); uart_port_lock_irqsave(&sport->port, &flags); ucr2 = imx_uart_readl(sport, UCR2); @@ -1587,7 +1626,7 @@ static void imx_uart_shutdown(struct uart_port *port) /* * Stop our timer. */ - del_timer_sync(&sport->timer); + timer_delete_sync(&sport->timer); /* * Disable all interrupts, port and break condition. @@ -1674,7 +1713,7 @@ static void imx_uart_shutdown(struct uart_port *port) /* called with port.lock taken and irqs off */ static void imx_uart_flush_buffer(struct uart_port *port) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); struct scatterlist *sgl = &sport->tx_sgl[0]; if (!sport->dma_chan_tx) @@ -1701,7 +1740,7 @@ static void imx_uart_set_termios(struct uart_port *port, struct ktermios *termios, const struct ktermios *old) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); unsigned long flags; u32 ucr2, old_ucr2, ufcr; unsigned int baud, quot; @@ -1720,7 +1759,7 @@ imx_uart_set_termios(struct uart_port *port, struct ktermios *termios, old_csize = CS8; } - del_timer_sync(&sport->timer); + timer_delete_sync(&sport->timer); /* * Ask the core to calculate the divisor for us. @@ -1904,7 +1943,7 @@ imx_uart_verify_port(struct uart_port *port, struct serial_struct *ser) static int imx_uart_poll_init(struct uart_port *port) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); unsigned long flags; u32 ucr1, ucr2; int retval; @@ -1916,7 +1955,7 @@ static int imx_uart_poll_init(struct uart_port *port) if (retval) clk_disable_unprepare(sport->clk_ipg); - imx_uart_setup_ufcr(sport, TXTL_DEFAULT, RXTL_DEFAULT); + imx_uart_setup_ufcr(sport, TXTL_DEFAULT, sport->rxtl); uart_port_lock_irqsave(&sport->port, &flags); @@ -1953,7 +1992,7 @@ static int imx_uart_poll_init(struct uart_port *port) static int imx_uart_poll_get_char(struct uart_port *port) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); if (!(imx_uart_readl(sport, USR2) & USR2_RDR)) return NO_POLL_CHAR; @@ -1962,7 +2001,7 @@ static int imx_uart_poll_get_char(struct uart_port *port) static void imx_uart_poll_put_char(struct uart_port *port, unsigned char c) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); unsigned int status; /* drain */ @@ -1984,7 +2023,7 @@ static void imx_uart_poll_put_char(struct uart_port *port, unsigned char c) static int imx_uart_rs485_config(struct uart_port *port, struct ktermios *termios, struct serial_rs485 *rs485conf) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); u32 ucr2, ufcr; if (rs485conf->flags & SER_RS485_ENABLED) { @@ -2008,7 +2047,7 @@ static int imx_uart_rs485_config(struct uart_port *port, struct ktermios *termio /* If the receiver trigger is 0, set it to a default value */ ufcr = imx_uart_readl(sport, UFCR); if ((ufcr & UFCR_RXTL_MASK) == 0) - imx_uart_setup_ufcr(sport, TXTL_DEFAULT, RXTL_DEFAULT); + imx_uart_setup_ufcr(sport, TXTL_DEFAULT, sport->rxtl); imx_uart_start_rx(port); } @@ -2043,32 +2082,40 @@ static struct imx_port *imx_uart_ports[UART_NR]; #if IS_ENABLED(CONFIG_SERIAL_IMX_CONSOLE) static void imx_uart_console_putchar(struct uart_port *port, unsigned char ch) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = to_imx_port(port); while (imx_uart_readl(sport, imx_uart_uts_reg(sport)) & UTS_TXFULL) barrier(); imx_uart_writel(sport, ch, URTX0); + + sport->last_putchar_was_newline = (ch == '\n'); } -/* - * Interrupts are disabled on entering - */ -static void -imx_uart_console_write(struct console *co, const char *s, unsigned int count) +static void imx_uart_console_device_lock(struct console *co, unsigned long *flags) +{ + struct uart_port *up = &imx_uart_ports[co->index]->port; + + return __uart_port_lock_irqsave(up, flags); +} + +static void imx_uart_console_device_unlock(struct console *co, unsigned long flags) +{ + struct uart_port *up = &imx_uart_ports[co->index]->port; + + return __uart_port_unlock_irqrestore(up, flags); +} + +static void imx_uart_console_write_atomic(struct console *co, + struct nbcon_write_context *wctxt) { struct imx_port *sport = imx_uart_ports[co->index]; + struct uart_port *port = &sport->port; struct imx_port_ucrs old_ucr; - unsigned long flags; unsigned int ucr1, usr2; - int locked = 1; - if (sport->port.sysrq) - locked = 0; - else if (oops_in_progress) - locked = uart_port_trylock_irqsave(&sport->port, &flags); - else - uart_port_lock_irqsave(&sport->port, &flags); + if (!nbcon_enter_unsafe(wctxt)) + return; /* * First, save UCR1/2/3 and then disable interrupts @@ -2082,10 +2129,12 @@ imx_uart_console_write(struct console *co, const char *s, unsigned int count) ucr1 &= ~(UCR1_TRDYEN | UCR1_RRDYEN | UCR1_RTSDEN); imx_uart_writel(sport, ucr1, UCR1); - imx_uart_writel(sport, old_ucr.ucr2 | UCR2_TXEN, UCR2); - uart_console_write(&sport->port, s, count, imx_uart_console_putchar); + if (!sport->last_putchar_was_newline) + uart_console_write(port, "\n", 1, imx_uart_console_putchar); + uart_console_write(port, wctxt->outbuf, wctxt->len, + imx_uart_console_putchar); /* * Finally, wait for transmitter to become empty @@ -2095,8 +2144,73 @@ imx_uart_console_write(struct console *co, const char *s, unsigned int count) 0, USEC_PER_SEC, false, sport, USR2); imx_uart_ucrs_restore(sport, &old_ucr); - if (locked) - uart_port_unlock_irqrestore(&sport->port, flags); + nbcon_exit_unsafe(wctxt); +} + +static void imx_uart_console_write_thread(struct console *co, + struct nbcon_write_context *wctxt) +{ + struct imx_port *sport = imx_uart_ports[co->index]; + struct uart_port *port = &sport->port; + struct imx_port_ucrs old_ucr; + unsigned int ucr1, usr2; + + if (!nbcon_enter_unsafe(wctxt)) + return; + + /* + * First, save UCR1/2/3 and then disable interrupts + */ + imx_uart_ucrs_save(sport, &old_ucr); + ucr1 = old_ucr.ucr1; + + if (imx_uart_is_imx1(sport)) + ucr1 |= IMX1_UCR1_UARTCLKEN; + ucr1 |= UCR1_UARTEN; + ucr1 &= ~(UCR1_TRDYEN | UCR1_RRDYEN | UCR1_RTSDEN); + + imx_uart_writel(sport, ucr1, UCR1); + imx_uart_writel(sport, old_ucr.ucr2 | UCR2_TXEN, UCR2); + + if (nbcon_exit_unsafe(wctxt)) { + int len = READ_ONCE(wctxt->len); + int i; + + /* + * Write out the message. Toggle unsafe for each byte in order + * to give another (higher priority) context the opportunity + * for a friendly takeover. If such a takeover occurs, this + * context must reacquire ownership in order to perform final + * actions (such as re-enabling the interrupts). + * + * IMPORTANT: wctxt->outbuf and wctxt->len are no longer valid + * after a reacquire so writing the message must be + * aborted. + */ + for (i = 0; i < len; i++) { + if (!nbcon_enter_unsafe(wctxt)) + break; + + uart_console_write(port, wctxt->outbuf + i, 1, + imx_uart_console_putchar); + + if (!nbcon_exit_unsafe(wctxt)) + break; + } + } + + while (!nbcon_enter_unsafe(wctxt)) + nbcon_reacquire_nobuf(wctxt); + + /* + * Finally, wait for transmitter to become empty + * and restore UCR1/2/3 + */ + read_poll_timeout(imx_uart_readl, usr2, usr2 & USR2_TXDC, + 0, USEC_PER_SEC, false, sport, USR2); + imx_uart_ucrs_restore(sport, &old_ucr); + + nbcon_exit_unsafe(wctxt); } /* @@ -2188,12 +2302,14 @@ imx_uart_console_setup(struct console *co, char *options) if (retval) goto error_console; + sport->last_putchar_was_newline = true; + if (options) uart_parse_options(options, &baud, &parity, &bits, &flow); else imx_uart_console_get_options(sport, &baud, &parity, &bits); - imx_uart_setup_ufcr(sport, TXTL_DEFAULT, RXTL_DEFAULT); + imx_uart_setup_ufcr(sport, TXTL_DEFAULT, sport->rxtl); retval = uart_set_options(&sport->port, co, baud, parity, bits, flow); @@ -2224,11 +2340,14 @@ imx_uart_console_exit(struct console *co) static struct uart_driver imx_uart_uart_driver; static struct console imx_uart_console = { .name = DEV_NAME, - .write = imx_uart_console_write, + .write_atomic = imx_uart_console_write_atomic, + .write_thread = imx_uart_console_write_thread, + .device_lock = imx_uart_console_device_lock, + .device_unlock = imx_uart_console_device_unlock, + .flags = CON_PRINTBUFFER | CON_NBCON, .device = uart_console_device, .setup = imx_uart_console_setup, .exit = imx_uart_console_exit, - .flags = CON_PRINTBUFFER, .index = -1, .data = &imx_uart_uart_driver, }; @@ -2470,10 +2589,10 @@ static int imx_uart_probe(struct platform_device *pdev) imx_uart_writel(sport, ucr3, UCR3); } - hrtimer_init(&sport->trigger_start_tx, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - hrtimer_init(&sport->trigger_stop_tx, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - sport->trigger_start_tx.function = imx_trigger_start_tx; - sport->trigger_stop_tx.function = imx_trigger_stop_tx; + hrtimer_setup(&sport->trigger_start_tx, imx_trigger_start_tx, CLOCK_MONOTONIC, + HRTIMER_MODE_REL); + hrtimer_setup(&sport->trigger_stop_tx, imx_trigger_stop_tx, CLOCK_MONOTONIC, + HRTIMER_MODE_REL); /* * Allocate the IRQ(s) i.MX1 has three interrupts whereas later @@ -2575,16 +2694,35 @@ static void imx_uart_save_context(struct imx_port *sport) uart_port_unlock_irqrestore(&sport->port, flags); } +/* called with irq off */ static void imx_uart_enable_wakeup(struct imx_port *sport, bool on) { - u32 ucr3; + struct tty_port *port = &sport->port.state->port; + struct device *tty_dev; + bool may_wake = false, wake_active = false; + u32 ucr3, usr1; + + scoped_guard(tty_port_tty, port) { + struct tty_struct *tty = scoped_tty(); + + tty_dev = tty->dev; + may_wake = tty_dev && device_may_wakeup(tty_dev); + } + + /* only configure the wake register when device set as wakeup source */ + if (!may_wake) + return; + + uart_port_lock_irq(&sport->port); + usr1 = imx_uart_readl(sport, USR1); ucr3 = imx_uart_readl(sport, UCR3); if (on) { imx_uart_writel(sport, USR1_AWAKE, USR1); ucr3 |= UCR3_AWAKEN; } else { ucr3 &= ~UCR3_AWAKEN; + wake_active = usr1 & USR1_AWAKE; } imx_uart_writel(sport, ucr3, UCR3); @@ -2595,9 +2733,15 @@ static void imx_uart_enable_wakeup(struct imx_port *sport, bool on) ucr1 |= UCR1_RTSDEN; } else { ucr1 &= ~UCR1_RTSDEN; + wake_active = wake_active || (usr1 & USR1_RTSD); } imx_uart_writel(sport, ucr1, UCR1); } + + if (wake_active && irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq))) + pm_wakeup_event(tty_port_tty_get(port)->dev, 0); + + uart_port_unlock_irq(&sport->port); } static int imx_uart_suspend_noirq(struct device *dev) @@ -2697,7 +2841,7 @@ static const struct dev_pm_ops imx_uart_pm_ops = { static struct platform_driver imx_uart_platform_driver = { .probe = imx_uart_probe, - .remove_new = imx_uart_remove, + .remove = imx_uart_remove, .driver = { .name = "imx-uart", |