| /* |
| * xen console driver interface to hvc_console.c |
| * |
| * (c) 2007 Gerd Hoffmann <kraxel@suse.de> |
| * |
| * 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/types.h> |
| |
| #include <asm/xen/hypervisor.h> |
| #include <xen/page.h> |
| #include <xen/events.h> |
| #include <xen/interface/io/console.h> |
| #include <xen/hvc-console.h> |
| |
| #include "hvc_console.h" |
| |
| #define HVC_COOKIE 0x58656e /* "Xen" in hex */ |
| |
| static struct hvc_struct *hvc; |
| static int xencons_irq; |
| |
| /* ------------------------------------------------------------------ */ |
| |
| static inline struct xencons_interface *xencons_interface(void) |
| { |
| return mfn_to_virt(xen_start_info->console.domU.mfn); |
| } |
| |
| static inline void notify_daemon(void) |
| { |
| /* Use evtchn: this is called early, before irq is set up. */ |
| notify_remote_via_evtchn(xen_start_info->console.domU.evtchn); |
| } |
| |
| static int write_console(uint32_t vtermno, const char *data, int len) |
| { |
| struct xencons_interface *intf = xencons_interface(); |
| XENCONS_RING_IDX cons, prod; |
| int sent = 0; |
| |
| cons = intf->out_cons; |
| prod = intf->out_prod; |
| mb(); /* update queue values before going on */ |
| BUG_ON((prod - cons) > sizeof(intf->out)); |
| |
| while ((sent < len) && ((prod - cons) < sizeof(intf->out))) |
| intf->out[MASK_XENCONS_IDX(prod++, intf->out)] = data[sent++]; |
| |
| wmb(); /* write ring before updating pointer */ |
| intf->out_prod = prod; |
| |
| notify_daemon(); |
| return sent; |
| } |
| |
| static int read_console(uint32_t vtermno, char *buf, int len) |
| { |
| struct xencons_interface *intf = xencons_interface(); |
| XENCONS_RING_IDX cons, prod; |
| int recv = 0; |
| |
| cons = intf->in_cons; |
| prod = intf->in_prod; |
| mb(); /* get pointers before reading ring */ |
| BUG_ON((prod - cons) > sizeof(intf->in)); |
| |
| while (cons != prod && recv < len) |
| buf[recv++] = intf->in[MASK_XENCONS_IDX(cons++, intf->in)]; |
| |
| mb(); /* read ring before consuming */ |
| intf->in_cons = cons; |
| |
| notify_daemon(); |
| return recv; |
| } |
| |
| static struct hv_ops hvc_ops = { |
| .get_chars = read_console, |
| .put_chars = write_console, |
| }; |
| |
| static int __init xen_init(void) |
| { |
| struct hvc_struct *hp; |
| |
| if (!is_running_on_xen()) |
| return 0; |
| |
| xencons_irq = bind_evtchn_to_irq(xen_start_info->console.domU.evtchn); |
| if (xencons_irq < 0) |
| xencons_irq = 0 /* NO_IRQ */; |
| hp = hvc_alloc(HVC_COOKIE, xencons_irq, &hvc_ops, 256); |
| if (IS_ERR(hp)) |
| return PTR_ERR(hp); |
| |
| hvc = hp; |
| return 0; |
| } |
| |
| static void __exit xen_fini(void) |
| { |
| if (hvc) |
| hvc_remove(hvc); |
| } |
| |
| static int xen_cons_init(void) |
| { |
| if (!is_running_on_xen()) |
| return 0; |
| |
| hvc_instantiate(HVC_COOKIE, 0, &hvc_ops); |
| return 0; |
| } |
| |
| module_init(xen_init); |
| module_exit(xen_fini); |
| console_initcall(xen_cons_init); |
| |
| static void raw_console_write(const char *str, int len) |
| { |
| while(len > 0) { |
| int rc = HYPERVISOR_console_io(CONSOLEIO_write, len, (char *)str); |
| if (rc <= 0) |
| break; |
| |
| str += rc; |
| len -= rc; |
| } |
| } |
| |
| #ifdef CONFIG_EARLY_PRINTK |
| static void xenboot_write_console(struct console *console, const char *string, |
| unsigned len) |
| { |
| unsigned int linelen, off = 0; |
| const char *pos; |
| |
| raw_console_write(string, len); |
| |
| while (off < len && NULL != (pos = strchr(string+off, '\n'))) { |
| linelen = pos-string+off; |
| if (off + linelen > len) |
| break; |
| write_console(0, string+off, linelen); |
| write_console(0, "\r\n", 2); |
| off += linelen + 1; |
| } |
| if (off < len) |
| write_console(0, string+off, len-off); |
| } |
| |
| struct console xenboot_console = { |
| .name = "xenboot", |
| .write = xenboot_write_console, |
| .flags = CON_PRINTBUFFER | CON_BOOT | CON_ANYTIME, |
| }; |
| #endif /* CONFIG_EARLY_PRINTK */ |
| |
| void xen_raw_console_write(const char *str) |
| { |
| raw_console_write(str, strlen(str)); |
| } |
| |
| void xen_raw_printk(const char *fmt, ...) |
| { |
| static char buf[512]; |
| va_list ap; |
| |
| va_start(ap, fmt); |
| vsnprintf(buf, sizeof(buf), fmt, ap); |
| va_end(ap); |
| |
| xen_raw_console_write(buf); |
| } |