diff options
Diffstat (limited to 'arch/xtensa/platforms/iss/console.c')
-rw-r--r-- | arch/xtensa/platforms/iss/console.c | 297 |
1 files changed, 297 insertions, 0 deletions
diff --git a/arch/xtensa/platforms/iss/console.c b/arch/xtensa/platforms/iss/console.c new file mode 100644 index 00000000000..9141e369073 --- /dev/null +++ b/arch/xtensa/platforms/iss/console.c @@ -0,0 +1,297 @@ +/* + * arch/xtensa/platform-iss/console.c + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2001-2005 Tensilica Inc. + * Authors Christian Zankel, Joe Taylor + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/console.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/mm.h> +#include <linux/major.h> +#include <linux/param.h> +#include <linux/serial.h> +#include <linux/serialP.h> + +#include <asm/uaccess.h> +#include <asm/irq.h> + +#include <asm/platform/simcall.h> + +#include <linux/tty.h> +#include <linux/tty_flip.h> + +#ifdef SERIAL_INLINE +#define _INLINE_ inline +#endif + +#define SERIAL_MAX_NUM_LINES 1 +#define SERIAL_TIMER_VALUE (20 * HZ) + +static struct tty_driver *serial_driver; +static struct timer_list serial_timer; + +static DEFINE_SPINLOCK(timer_lock); + +int errno; + +static int __simc (int a, int b, int c, int d, int e, int f) __attribute__((__noinline__)); +static int __simc (int a, int b, int c, int d, int e, int f) +{ + int ret; + __asm__ __volatile__ ("simcall\n" + "mov %0, a2\n" + "mov %1, a3\n" : "=a" (ret), "=a" (errno) + : : "a2", "a3"); + return ret; +} + +static char *serial_version = "0.1"; +static char *serial_name = "ISS serial driver"; + +/* + * This routine is called whenever a serial port is opened. It + * enables interrupts for a serial port, linking in its async structure into + * the IRQ chain. It also performs the serial-specific + * initialization for the tty structure. + */ + +static void rs_poll(unsigned long); + +static int rs_open(struct tty_struct *tty, struct file * filp) +{ + int line = tty->index; + + if ((line < 0) || (line >= SERIAL_MAX_NUM_LINES)) + return -ENODEV; + + spin_lock(&timer_lock); + + if (tty->count == 1) { + init_timer(&serial_timer); + serial_timer.data = (unsigned long) tty; + serial_timer.function = rs_poll; + mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE); + } + spin_unlock(&timer_lock); + + return 0; +} + + +/* + * ------------------------------------------------------------ + * iss_serial_close() + * + * This routine is called when the serial port gets closed. First, we + * wait for the last remaining data to be sent. Then, we unlink its + * async structure from the interrupt chain if necessary, and we free + * that IRQ if nothing is left in the chain. + * ------------------------------------------------------------ + */ +static void rs_close(struct tty_struct *tty, struct file * filp) +{ + spin_lock(&timer_lock); + if (tty->count == 1) + del_timer_sync(&serial_timer); + spin_unlock(&timer_lock); +} + + +static int rs_write(struct tty_struct * tty, + const unsigned char *buf, int count) +{ + /* see drivers/char/serialX.c to reference original version */ + + __simc (SYS_write, 1, (unsigned long)buf, count, 0, 0); + return count; +} + +static void rs_poll(unsigned long priv) +{ + struct tty_struct* tty = (struct tty_struct*) priv; + + struct timeval tv = { .tv_sec = 0, .tv_usec = 0 }; + int i = 0; + unsigned char c; + + spin_lock(&timer_lock); + + while (__simc(SYS_select_one, 0, XTISS_SELECT_ONE_READ, (int)&tv,0,0)){ + __simc (SYS_read, 0, (unsigned long)&c, 1, 0, 0); + tty_insert_flip_char(tty, c, TTY_NORMAL); + i++; + } + + if (i) + tty_flip_buffer_push(tty); + + + mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE); + spin_unlock(&timer_lock); +} + + +static void rs_put_char(struct tty_struct *tty, unsigned char ch) +{ + char buf[2]; + + if (!tty) + return; + + buf[0] = ch; + buf[1] = '\0'; /* Is this NULL necessary? */ + __simc (SYS_write, 1, (unsigned long) buf, 1, 0, 0); +} + +static void rs_flush_chars(struct tty_struct *tty) +{ +} + +static int rs_write_room(struct tty_struct *tty) +{ + /* Let's say iss can always accept 2K characters.. */ + return 2 * 1024; +} + +static int rs_chars_in_buffer(struct tty_struct *tty) +{ + /* the iss doesn't buffer characters */ + return 0; +} + +static void rs_hangup(struct tty_struct *tty) +{ + /* Stub, once again.. */ +} + +static void rs_wait_until_sent(struct tty_struct *tty, int timeout) +{ + /* Stub, once again.. */ +} + +static int rs_read_proc(char *page, char **start, off_t off, int count, + int *eof, void *data) +{ + int len = 0; + off_t begin = 0; + + len += sprintf(page, "serinfo:1.0 driver:%s\n", serial_version); + *eof = 1; + + if (off >= len + begin) + return 0; + + *start = page + (off - begin); + return ((count < begin + len - off) ? count : begin + len - off); +} + + +static struct tty_operations serial_ops = { + .open = rs_open, + .close = rs_close, + .write = rs_write, + .put_char = rs_put_char, + .flush_chars = rs_flush_chars, + .write_room = rs_write_room, + .chars_in_buffer = rs_chars_in_buffer, + .hangup = rs_hangup, + .wait_until_sent = rs_wait_until_sent, + .read_proc = rs_read_proc +}; + +int __init rs_init(void) +{ + serial_driver = alloc_tty_driver(1); + + printk ("%s %s\n", serial_name, serial_version); + + /* Initialize the tty_driver structure */ + + serial_driver->owner = THIS_MODULE; + serial_driver->driver_name = "iss_serial"; + serial_driver->name = "ttyS"; + serial_driver->major = TTY_MAJOR; + serial_driver->minor_start = 64; + serial_driver->type = TTY_DRIVER_TYPE_SERIAL; + serial_driver->subtype = SERIAL_TYPE_NORMAL; + serial_driver->init_termios = tty_std_termios; + serial_driver->init_termios.c_cflag = + B9600 | CS8 | CREAD | HUPCL | CLOCAL; + serial_driver->flags = TTY_DRIVER_REAL_RAW; + + tty_set_operations(serial_driver, &serial_ops); + + if (tty_register_driver(serial_driver)) + panic("Couldn't register serial driver\n"); + return 0; +} + + +static __exit void rs_exit(void) +{ + int error; + + if ((error = tty_unregister_driver(serial_driver))) + printk("ISS_SERIAL: failed to unregister serial driver (%d)\n", + error); + put_tty_driver(serial_driver); +} + + +/* We use `late_initcall' instead of just `__initcall' as a workaround for + * the fact that (1) simcons_tty_init can't be called before tty_init, + * (2) tty_init is called via `module_init', (3) if statically linked, + * module_init == device_init, and (4) there's no ordering of init lists. + * We can do this easily because simcons is always statically linked, but + * other tty drivers that depend on tty_init and which must use + * `module_init' to declare their init routines are likely to be broken. + */ + +late_initcall(rs_init); + + +#ifdef CONFIG_SERIAL_CONSOLE + +static void iss_console_write(struct console *co, const char *s, unsigned count) +{ + int len = strlen(s); + + if (s != 0 && *s != 0) + __simc (SYS_write, 1, (unsigned long)s, + count < len ? count : len,0,0); +} + +static struct tty_driver* iss_console_device(struct console *c, int *index) +{ + *index = c->index; + return serial_driver; +} + + +static struct console sercons = { + .name = "ttyS", + .write = iss_console_write, + .device = iss_console_device, + .flags = CON_PRINTBUFFER, + .index = -1 +}; + +static int __init iss_console_init(void) +{ + register_console(&sercons); + return 0; +} + +console_initcall(iss_console_init); + +#endif /* CONFIG_SERIAL_CONSOLE */ + |