diff options
Diffstat (limited to 'drivers/serial')
| -rw-r--r-- | drivers/serial/Kconfig | 21 | ||||
| -rw-r--r-- | drivers/serial/Makefile | 1 | ||||
| -rw-r--r-- | drivers/serial/altera_jtaguart.c | 504 |
3 files changed, 526 insertions, 0 deletions
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index 577d2762a4f..f4050e67846 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -1523,4 +1523,25 @@ config SERIAL_GRLIB_GAISLER_APBUART_CONSOLE help Support for running a console on the GRLIB APBUART +config SERIAL_ALTERA_JTAGUART + tristate "Altera JTAG UART support" + select SERIAL_CORE + help + This driver supports the Altera JTAG UART port. + +config SERIAL_ALTERA_JTAGUART_CONSOLE + bool "Altera JTAG UART console support" + depends on SERIAL_ALTERA_JTAGUART=y + select SERIAL_CORE_CONSOLE + help + Enable a Altera JTAG UART port to be the system console. + +config SERIAL_ALTERA_JTAGUART_CONSOLE_BYPASS + bool "Bypass output when no connection" + depends on SERIAL_ALTERA_JTAGUART_CONSOLE + select SERIAL_CORE_CONSOLE + help + Bypass console output and keep going even if there is no + JTAG terminal connection with the host. + endmenu diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile index 328f107346c..7f9d225d043 100644 --- a/drivers/serial/Makefile +++ b/drivers/serial/Makefile @@ -82,3 +82,4 @@ obj-$(CONFIG_KGDB_SERIAL_CONSOLE) += kgdboc.o obj-$(CONFIG_SERIAL_QE) += ucc_uart.o obj-$(CONFIG_SERIAL_TIMBERDALE) += timbuart.o obj-$(CONFIG_SERIAL_GRLIB_GAISLER_APBUART) += apbuart.o +obj-$(CONFIG_SERIAL_ALTERA_JTAGUART) += altera_jtaguart.o diff --git a/drivers/serial/altera_jtaguart.c b/drivers/serial/altera_jtaguart.c new file mode 100644 index 00000000000..f9b49b5ff5e --- /dev/null +++ b/drivers/serial/altera_jtaguart.c @@ -0,0 +1,504 @@ +/* + * altera_jtaguart.c -- Altera JTAG UART driver + * + * Based on mcf.c -- Freescale ColdFire UART driver + * + * (C) Copyright 2003-2007, Greg Ungerer <gerg@snapgear.com> + * (C) Copyright 2008, Thomas Chou <thomas@wytron.com.tw> + * (C) Copyright 2010, Tobias Klauser <tklauser@distanz.ch> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/console.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> +#include <linux/serial.h> +#include <linux/serial_core.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/altera_jtaguart.h> + +#define DRV_NAME "altera_jtaguart" + +/* + * Altera JTAG UART register definitions according to the Altera JTAG UART + * datasheet: http://www.altera.com/literature/hb/nios2/n2cpu_nii51009.pdf + */ + +#define ALTERA_JTAGUART_SIZE 8 + +#define ALTERA_JTAGUART_DATA_REG 0 + +#define ALTERA_JTAGUART_DATA_DATA_MSK 0x000000FF +#define ALTERA_JTAGUART_DATA_RVALID_MSK 0x00008000 +#define ALTERA_JTAGUART_DATA_RAVAIL_MSK 0xFFFF0000 +#define ALTERA_JTAGUART_DATA_RAVAIL_OFF 16 + +#define ALTERA_JTAGUART_CONTROL_REG 4 + +#define ALTERA_JTAGUART_CONTROL_RE_MSK 0x00000001 +#define ALTERA_JTAGUART_CONTROL_WE_MSK 0x00000002 +#define ALTERA_JTAGUART_CONTROL_RI_MSK 0x00000100 +#define ALTERA_JTAGUART_CONTROL_RI_OFF 8 +#define ALTERA_JTAGUART_CONTROL_WI_MSK 0x00000200 +#define ALTERA_JTAGUART_CONTROL_AC_MSK 0x00000400 +#define ALTERA_JTAGUART_CONTROL_WSPACE_MSK 0xFFFF0000 +#define ALTERA_JTAGUART_CONTROL_WSPACE_OFF 16 + +/* + * Local per-uart structure. + */ +struct altera_jtaguart { + struct uart_port port; + unsigned int sigs; /* Local copy of line sigs */ + unsigned long imr; /* Local IMR mirror */ +}; + +static unsigned int altera_jtaguart_tx_empty(struct uart_port *port) +{ + return (readl(port->membase + ALTERA_JTAGUART_CONTROL_REG) & + ALTERA_JTAGUART_CONTROL_WSPACE_MSK) ? TIOCSER_TEMT : 0; +} + +static unsigned int altera_jtaguart_get_mctrl(struct uart_port *port) +{ + return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS; +} + +static void altera_jtaguart_set_mctrl(struct uart_port *port, unsigned int sigs) +{ +} + +static void altera_jtaguart_start_tx(struct uart_port *port) +{ + struct altera_jtaguart *pp = + container_of(port, struct altera_jtaguart, port); + + pp->imr |= ALTERA_JTAGUART_CONTROL_WE_MSK; + writel(pp->imr, port->membase + ALTERA_JTAGUART_CONTROL_REG); +} + +static void altera_jtaguart_stop_tx(struct uart_port *port) +{ + struct altera_jtaguart *pp = + container_of(port, struct altera_jtaguart, port); + + pp->imr &= ~ALTERA_JTAGUART_CONTROL_WE_MSK; + writel(pp->imr, port->membase + ALTERA_JTAGUART_CONTROL_REG); +} + +static void altera_jtaguart_stop_rx(struct uart_port *port) +{ + struct altera_jtaguart *pp = + container_of(port, struct altera_jtaguart, port); + + pp->imr &= ~ALTERA_JTAGUART_CONTROL_RE_MSK; + writel(pp->imr, port->membase + ALTERA_JTAGUART_CONTROL_REG); +} + +static void altera_jtaguart_break_ctl(struct uart_port *port, int break_state) +{ +} + +static void altera_jtaguart_enable_ms(struct uart_port *port) +{ +} + +static void altera_jtaguart_set_termios(struct uart_port *port, + struct ktermios *termios, + struct ktermios *old) +{ + /* Just copy the old termios settings back */ + if (old) + tty_termios_copy_hw(termios, old); +} + +static void altera_jtaguart_rx_chars(struct altera_jtaguart *pp) +{ + struct uart_port *port = &pp->port; + unsigned char ch, flag; + unsigned long status; + + while ((status = readl(port->membase + ALTERA_JTAGUART_DATA_REG)) & + ALTERA_JTAGUART_DATA_RVALID_MSK) { + ch = status & ALTERA_JTAGUART_DATA_DATA_MSK; + flag = TTY_NORMAL; + port->icount.rx++; + + if (uart_handle_sysrq_char(port, ch)) + continue; + uart_insert_char(port, 0, 0, ch, flag); + } + + tty_flip_buffer_push(port->state->port.tty); +} + +static void altera_jtaguart_tx_chars(struct altera_jtaguart *pp) +{ + struct uart_port *port = &pp->port; + struct circ_buf *xmit = &port->state->xmit; + unsigned int pending, count; + + if (port->x_char) { + /* Send special char - probably flow control */ + writel(port->x_char, port->membase + ALTERA_JTAGUART_DATA_REG); + port->x_char = 0; + port->icount.tx++; + return; + } + + pending = uart_circ_chars_pending(xmit); + if (pending > 0) { + count = (readl(port->membase + ALTERA_JTAGUART_CONTROL_REG) & + ALTERA_JTAGUART_CONTROL_WSPACE_MSK) >> + ALTERA_JTAGUART_CONTROL_WSPACE_OFF; + if (count > pending) + count = pending; + if (count > 0) { + pending -= count; + while (count--) { + writel(xmit->buf[xmit->tail], + port->membase + ALTERA_JTAGUART_DATA_REG); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + port->icount.tx++; + } + if (pending < WAKEUP_CHARS) + uart_write_wakeup(port); + } + } + + if (pending == 0) { + pp->imr &= ~ALTERA_JTAGUART_CONTROL_WE_MSK; + writel(pp->imr, port->membase + ALTERA_JTAGUART_CONTROL_REG); + } +} + +static irqreturn_t altera_jtaguart_interrupt(int irq, void *data) +{ + struct uart_port *port = data; + struct altera_jtaguart *pp = + container_of(port, struct altera_jtaguart, port); + unsigned int isr; + + isr = (readl(port->membase + ALTERA_JTAGUART_CONTROL_REG) >> + ALTERA_JTAGUART_CONTROL_RI_OFF) & pp->imr; + + spin_lock(&port->lock); + + if (isr & ALTERA_JTAGUART_CONTROL_RE_MSK) + altera_jtaguart_rx_chars(pp); + if (isr & ALTERA_JTAGUART_CONTROL_WE_MSK) + altera_jtaguart_tx_chars(pp); + + spin_unlock(&port->lock); + + return IRQ_RETVAL(isr); +} + +static void altera_jtaguart_config_port(struct uart_port *port, int flags) +{ + port->type = PORT_ALTERA_JTAGUART; + + /* Clear mask, so no surprise interrupts. */ + writel(0, port->membase + ALTERA_JTAGUART_CONTROL_REG); +} + +static int altera_jtaguart_startup(struct uart_port *port) +{ + struct altera_jtaguart *pp = + container_of(port, struct altera_jtaguart, port); + unsigned long flags; + int ret; + + ret = request_irq(port->irq, altera_jtaguart_interrupt, IRQF_DISABLED, + DRV_NAME, port); + if (ret) { + pr_err(DRV_NAME ": unable to attach Altera JTAG UART %d " + "interrupt vector=%d\n", port->line, port->irq); + return ret; + } + + spin_lock_irqsave(&port->lock, flags); + + /* Enable RX interrupts now */ + pp->imr = ALTERA_JTAGUART_CONTROL_RE_MSK; + writel(pp->imr, port->membase + ALTERA_JTAGUART_CONTROL_REG); + + spin_unlock_irqrestore(&port->lock, flags); + + return 0; +} + +static void altera_jtaguart_shutdown(struct uart_port *port) +{ + struct altera_jtaguart *pp = + container_of(port, struct altera_jtaguart, port); + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); + + /* Disable all interrupts now */ + pp->imr = 0; + writel(pp->imr, port->membase + ALTERA_JTAGUART_CONTROL_REG); + + spin_unlock_irqrestore(&port->lock, flags); + + free_irq(port->irq, port); +} + +static const char *altera_jtaguart_type(struct uart_port *port) +{ + return (port->type == PORT_ALTERA_JTAGUART) ? "Altera JTAG UART" : NULL; +} + +static int altera_jtaguart_request_port(struct uart_port *port) +{ + /* UARTs always present */ + return 0; +} + +static void altera_jtaguart_release_port(struct uart_port *port) +{ + /* Nothing to release... */ +} + +static int altera_jtaguart_verify_port(struct uart_port *port, + struct serial_struct *ser) +{ + if (ser->type != PORT_UNKNOWN && ser->type != PORT_ALTERA_JTAGUART) + return -EINVAL; + return 0; +} + +/* + * Define the basic serial functions we support. + */ +static struct uart_ops altera_jtaguart_ops = { + .tx_empty = altera_jtaguart_tx_empty, + .get_mctrl = altera_jtaguart_get_mctrl, + .set_mctrl = altera_jtaguart_set_mctrl, + .start_tx = altera_jtaguart_start_tx, + .stop_tx = altera_jtaguart_stop_tx, + .stop_rx = altera_jtaguart_stop_rx, + .enable_ms = altera_jtaguart_enable_ms, + .break_ctl = altera_jtaguart_break_ctl, + .startup = altera_jtaguart_startup, + .shutdown = altera_jtaguart_shutdown, + .set_termios = altera_jtaguart_set_termios, + .type = altera_jtaguart_type, + .request_port = altera_jtaguart_request_port, + .release_port = altera_jtaguart_release_port, + .config_port = altera_jtaguart_config_port, + .verify_port = altera_jtaguart_verify_port, +}; + +#define ALTERA_JTAGUART_MAXPORTS 1 +static struct altera_jtaguart altera_jtaguart_ports[ALTERA_JTAGUART_MAXPORTS]; + +#if defined(CONFIG_SERIAL_ALTERA_JTAGUART_CONSOLE) + +int __init early_altera_jtaguart_setup(struct altera_jtaguart_platform_uart + *platp) +{ + struct uart_port *port; + int i; + + for (i = 0; i < ALTERA_JTAGUART_MAXPORTS && platp[i].mapbase; i++) { + port = &altera_jtaguart_ports[i].port; + + port->line = i; + port->type = PORT_ALTERA_JTAGUART; + port->mapbase = platp[i].mapbase; + port->membase = ioremap(port->mapbase, ALTERA_JTAGUART_SIZE); + port->iotype = SERIAL_IO_MEM; + port->irq = platp[i].irq; + port->flags = ASYNC_BOOT_AUTOCONF; + port->ops = &altera_jtaguart_ops; + } + + return 0; +} + +#if defined(CONFIG_SERIAL_ALTERA_JTAGUART_CONSOLE_BYPASS) +static void altera_jtaguart_console_putc(struct console *co, const char c) +{ + struct uart_port *port = &(altera_jtaguart_ports + co->index)->port; + unsigned long status; + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); + while (((status = readl(port->membase + ALTERA_JTAGUART_CONTROL_REG)) & + ALTERA_JTAGUART_CONTROL_WSPACE_MSK) == 0) { + if ((status & ALTERA_JTAGUART_CONTROL_AC_MSK) == 0) { + spin_unlock_irqrestore(&port->lock, flags); + return; /* no connection activity */ + } + spin_unlock_irqrestore(&port->lock, flags); + cpu_relax(); + spin_lock_irqsave(&port->lock, flags); + } + writel(c, port->membase + ALTERA_JTAGUART_DATA_REG); + spin_unlock_irqrestore(&port->lock, flags); +} +#else +static void altera_jtaguart_console_putc(struct console *co, const char c) +{ + struct uart_port *port = &(altera_jtaguart_ports + co->index)->port; + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); + while ((readl(port->membase + ALTERA_JTAGUART_CONTROL_REG) & + ALTERA_JTAGUART_CONTROL_WSPACE_MSK) == 0) { + spin_unlock_irqrestore(&port->lock, flags); + cpu_relax(); + spin_lock_irqsave(&port->lock, flags); + } + writel(c, port->membase + ALTERA_JTAGUART_DATA_REG); + spin_unlock_irqrestore(&port->lock, flags); +} +#endif + +static void altera_jtaguart_console_write(struct console *co, const char *s, + unsigned int count) +{ + for (; count; count--, s++) { + altera_jtaguart_console_putc(co, *s); + if (*s == '\n') + altera_jtaguart_console_putc(co, '\r'); + } +} + +static int __init altera_jtaguart_console_setup(struct console *co, + char *options) +{ + struct uart_port *port; + + if (co->index < 0 || co->index >= ALTERA_JTAGUART_MAXPORTS) + return -EINVAL; + port = &altera_jtaguart_ports[co->index].port; + if (port->membase == 0) + return -ENODEV; + return 0; +} + +static struct uart_driver altera_jtaguart_driver; + +static struct console altera_jtaguart_console = { + .name = "ttyJ", + .write = altera_jtaguart_console_write, + .device = uart_console_device, + .setup = altera_jtaguart_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &altera_jtaguart_driver, +}; + +static int __init altera_jtaguart_console_init(void) +{ + register_console(&altera_jtaguart_console); + return 0; +} + +console_initcall(altera_jtaguart_console_init); + +#define ALTERA_JTAGUART_CONSOLE (&altera_jtaguart_console) + +#else + +#define ALTERA_JTAGUART_CONSOLE NULL + +#endif /* CONFIG_ALTERA_JTAGUART_CONSOLE */ + +static struct uart_driver altera_jtaguart_driver = { + .owner = THIS_MODULE, + .driver_name = "altera_jtaguart", + .dev_name = "ttyJ", + .major = ALTERA_JTAGUART_MAJOR, + .minor = ALTERA_JTAGUART_MINOR, + .nr = ALTERA_JTAGUART_MAXPORTS, + .cons = ALTERA_JTAGUART_CONSOLE, +}; + +static int __devinit altera_jtaguart_probe(struct platform_device *pdev) +{ + struct altera_jtaguart_platform_uart *platp = pdev->dev.platform_data; + struct uart_port *port; + int i; + + for (i = 0; i < ALTERA_JTAGUART_MAXPORTS && platp[i].mapbase; i++) { + port = &altera_jtaguart_ports[i].port; + + port->line = i; + port->type = PORT_ALTERA_JTAGUART; + port->mapbase = platp[i].mapbase; + port->membase = ioremap(port->mapbase, ALTERA_JTAGUART_SIZE); + port->iotype = SERIAL_IO_MEM; + port->irq = platp[i].irq; + port->ops = &altera_jtaguart_ops; + port->flags = ASYNC_BOOT_AUTOCONF; + + uart_add_one_port(&altera_jtaguart_driver, port); + } + + return 0; +} + +static int __devexit altera_jtaguart_remove(struct platform_device *pdev) +{ + struct uart_port *port; + int i; + + for (i = 0; i < ALTERA_JTAGUART_MAXPORTS; i++) { + port = &altera_jtaguart_ports[i].port; + if (port) + uart_remove_one_port(&altera_jtaguart_driver, port); + } + + return 0; +} + +static struct platform_driver altera_jtaguart_platform_driver = { + .probe = altera_jtaguart_probe, + .remove = __devexit_p(altera_jtaguart_remove), + .driver = { + .name = DRV_NAME, + .owner = THIS_MODULE, + }, +}; + +static int __init altera_jtaguart_init(void) +{ + int rc; + + rc = uart_register_driver(&altera_jtaguart_driver); + if (rc) + return rc; + rc = platform_driver_register(&altera_jtaguart_platform_driver); + if (rc) { + uart_unregister_driver(&altera_jtaguart_driver); + return rc; + } + return 0; +} + +static void __exit altera_jtaguart_exit(void) +{ + platform_driver_unregister(&altera_jtaguart_platform_driver); + uart_unregister_driver(&altera_jtaguart_driver); +} + +module_init(altera_jtaguart_init); +module_exit(altera_jtaguart_exit); + +MODULE_DESCRIPTION("Altera JTAG UART driver"); +MODULE_AUTHOR("Thomas Chou <thomas@wytron.com.tw>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRV_NAME); |