/* * IBM RTAS driver interface to hvc_console.c * * (C) Copyright IBM Corporation 2001-2005 * (C) Copyright Red Hat, Inc. 2005 * * Author(s): Maximino Augilar <IBM STI Design Center> * : Ryan S. Arnold <rsa@us.ibm.com> * : Utz Bacher <utz.bacher@de.ibm.com> * : David Woodhouse <dwmw2@infradead.org> * * inspired by drivers/char/hvc_console.c * written by Anton Blanchard and Paul Mackerras * * 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. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include <linux/console.h> #include <linux/delay.h> #include <linux/err.h> #include <linux/init.h> #include <linux/moduleparam.h> #include <linux/types.h> #include <asm/irq.h> #include <asm/rtas.h> #include "hvc_console.h" #define hvc_rtas_cookie 0x67781e15 struct hvc_struct *hvc_rtas_dev; #define RTASCONS_PUT_ATTEMPTS 16 static int rtascons_put_char_token = RTAS_UNKNOWN_SERVICE; static int rtascons_get_char_token = RTAS_UNKNOWN_SERVICE; static int rtascons_put_delay = 100; module_param_named(put_delay, rtascons_put_delay, int, 0644); static inline int hvc_rtas_write_console(uint32_t vtermno, const char *buf, int count) { int done; /* if there is more than one character to be displayed, wait a bit */ for (done = 0; done < count; done++) { int result; result = rtas_call(rtascons_put_char_token, 1, 1, NULL, buf[done]); if (result) break; } /* the calling routine expects to receive the number of bytes sent */ return done; } static int hvc_rtas_read_console(uint32_t vtermno, char *buf, int count) { int i; for (i = 0; i < count; i++) { int c, err; err = rtas_call(rtascons_get_char_token, 0, 2, &c); if (err) break; buf[i] = c; } return i; } static struct hv_ops hvc_rtas_get_put_ops = { .get_chars = hvc_rtas_read_console, .put_chars = hvc_rtas_write_console, }; static int hvc_rtas_init(void) { struct hvc_struct *hp; if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE) rtascons_put_char_token = rtas_token("put-term-char"); if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE) return -EIO; if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE) rtascons_get_char_token = rtas_token("get-term-char"); if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE) return -EIO; BUG_ON(hvc_rtas_dev); /* Allocate an hvc_struct for the console device we instantiated * earlier. Save off hp so that we can return it on exit */ hp = hvc_alloc(hvc_rtas_cookie, NO_IRQ, &hvc_rtas_get_put_ops); if (IS_ERR(hp)) return PTR_ERR(hp); hvc_rtas_dev = hp; return 0; } module_init(hvc_rtas_init); /* This will tear down the tty portion of the driver */ static void __exit hvc_rtas_exit(void) { /* Really the fun isn't over until the worker thread breaks down and the * tty cleans up */ if (hvc_rtas_dev) hvc_remove(hvc_rtas_dev); } module_exit(hvc_rtas_exit); /* This will happen prior to module init. There is no tty at this time? */ static int hvc_rtas_console_init(void) { rtascons_put_char_token = rtas_token("put-term-char"); if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE) return -EIO; rtascons_get_char_token = rtas_token("get-term-char"); if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE) return -EIO; hvc_instantiate(hvc_rtas_cookie, 0, &hvc_rtas_get_put_ops ); add_preferred_console("hvc", 0, NULL); return 0; } console_initcall(hvc_rtas_console_init);