[PATCH] xtensa: Architecture support for Tensilica Xtensa Part 8

The attached patches provides part 8 of an architecture implementation
for the Tensilica Xtensa CPU series.

Signed-off-by: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 303 insertions, 0 deletions

diff --git a/arch/xtensa/platform-iss/console.c b/arch/xtensa/platform-iss/console.c
new file mode 100644
index 000000000000..9e2b53f6a907
--- /dev/null
+++ b/arch/xtensa/platform-iss/console.c
@@ -0,0 +1,303 @@
+/*
+ * 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/config.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 <linux/console.h>
+
+#include <asm/uaccess.h>
+#include <asm/irq.h>
+
+#include <xtensa/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)
+{
+        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->flip.count++;
+                *tty->flip.char_buf_ptr++ = c;
+                *tty->flip.flag_buf_ptr++ = 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);
+}
+
+
+int register_serial(struct serial_struct*);
+void unregister_serial(int);
+
+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 */
+