diff options
Diffstat (limited to 'arch/v850/kernel/simcons.c')
| -rw-r--r-- | arch/v850/kernel/simcons.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/arch/v850/kernel/simcons.c b/arch/v850/kernel/simcons.c new file mode 100644 index 00000000000..7f0efaa025c --- /dev/null +++ b/arch/v850/kernel/simcons.c @@ -0,0 +1,166 @@ +/* + * arch/v850/kernel/simcons.c -- Console I/O for GDB v850e simulator + * + * Copyright (C) 2001,02,03 NEC Electronics Corporation + * Copyright (C) 2001,02,03 Miles Bader <miles@gnu.org> + * + * 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. + * + * Written by Miles Bader <miles@gnu.org> + */ + +#include <linux/kernel.h> +#include <linux/console.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> +#include <linux/tty_driver.h> +#include <linux/init.h> + +#include <asm/poll.h> +#include <asm/string.h> +#include <asm/simsyscall.h> + + +/* Low-level console. */ + +static void simcons_write (struct console *co, const char *buf, unsigned len) +{ + V850_SIM_SYSCALL (write, 1, buf, len); +} + +static int simcons_read (struct console *co, char *buf, unsigned len) +{ + return V850_SIM_SYSCALL (read, 0, buf, len); +} + +static struct tty_driver *tty_driver; +static struct tty_driver *simcons_device (struct console *c, int *index) +{ + *index = c->index; + return tty_driver; +} + +static struct console simcons = +{ + .name = "simcons", + .write = simcons_write, + .read = simcons_read, + .device = simcons_device, + .flags = CON_PRINTBUFFER, + .index = -1, +}; + +/* Higher level TTY interface. */ + +int simcons_tty_open (struct tty_struct *tty, struct file *filp) +{ + return 0; +} + +int simcons_tty_write (struct tty_struct *tty, + const unsigned char *buf, int count) +{ + return V850_SIM_SYSCALL (write, 1, buf, count); +} + +int simcons_tty_write_room (struct tty_struct *tty) +{ + /* Completely arbitrary. */ + return 0x100000; +} + +int simcons_tty_chars_in_buffer (struct tty_struct *tty) +{ + /* We have no buffer. */ + return 0; +} + +static struct tty_operations ops = { + .open = simcons_tty_open, + .write = simcons_tty_write, + .write_room = simcons_tty_write_room, + .chars_in_buffer = simcons_tty_chars_in_buffer, +}; + +int __init simcons_tty_init (void) +{ + struct tty_driver *driver = alloc_tty_driver(1); + int err; + if (!driver) + return -ENOMEM; + driver->name = "simcons"; + driver->major = TTY_MAJOR; + driver->minor_start = 64; + driver->type = TTY_DRIVER_TYPE_SYSCONS; + driver->init_termios = tty_std_termios; + tty_set_operations(driver, &ops); + err = tty_register_driver(driver); + if (err) { + put_tty_driver(driver); + return err; + } + tty_driver = driver; + return 0; +} +/* 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(simcons_tty_init); + +/* Poll for input on the console, and if there's any, deliver it to the + tty driver. */ +void simcons_poll_tty (struct tty_struct *tty) +{ + int flip = 0, send_break = 0; + struct pollfd pfd; + pfd.fd = 0; + pfd.events = POLLIN; + + if (V850_SIM_SYSCALL (poll, &pfd, 1, 0) > 0) { + if (pfd.revents & POLLIN) { + int left = TTY_FLIPBUF_SIZE - tty->flip.count; + + if (left > 0) { + unsigned char *buf = tty->flip.char_buf_ptr; + int rd = V850_SIM_SYSCALL (read, 0, buf, left); + + if (rd > 0) { + tty->flip.count += rd; + tty->flip.char_buf_ptr += rd; + memset (tty->flip.flag_buf_ptr, 0, rd); + tty->flip.flag_buf_ptr += rd; + flip = 1; + } else + send_break = 1; + } + } else if (pfd.revents & POLLERR) + send_break = 1; + } + + if (send_break) { + tty_insert_flip_char (tty, 0, TTY_BREAK); + flip = 1; + } + + if (flip) + tty_schedule_flip (tty); +} + +void simcons_poll_ttys (void) +{ + if (tty_driver && tty_driver->ttys[0]) + simcons_poll_tty (tty_driver->ttys[0]); +} + +void simcons_setup (void) +{ + V850_SIM_SYSCALL (make_raw, 0); + register_console (&simcons); + printk (KERN_INFO "Console: GDB V850E simulator stdio\n"); +} |