Jeremy Fitzhardinge | b536b4b | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 1 | /* |
| 2 | * xen console driver interface to hvc_console.c |
| 3 | * |
| 4 | * (c) 2007 Gerd Hoffmann <kraxel@suse.de> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 19 | */ |
| 20 | |
| 21 | #include <linux/console.h> |
| 22 | #include <linux/delay.h> |
| 23 | #include <linux/err.h> |
| 24 | #include <linux/init.h> |
| 25 | #include <linux/types.h> |
| 26 | |
| 27 | #include <asm/xen/hypervisor.h> |
| 28 | #include <xen/page.h> |
| 29 | #include <xen/events.h> |
| 30 | #include <xen/interface/io/console.h> |
| 31 | #include <xen/hvc-console.h> |
| 32 | |
| 33 | #include "hvc_console.h" |
| 34 | |
| 35 | #define HVC_COOKIE 0x58656e /* "Xen" in hex */ |
| 36 | |
| 37 | static struct hvc_struct *hvc; |
| 38 | static int xencons_irq; |
| 39 | |
| 40 | /* ------------------------------------------------------------------ */ |
| 41 | |
| 42 | static inline struct xencons_interface *xencons_interface(void) |
| 43 | { |
| 44 | return mfn_to_virt(xen_start_info->console.domU.mfn); |
| 45 | } |
| 46 | |
| 47 | static inline void notify_daemon(void) |
| 48 | { |
| 49 | /* Use evtchn: this is called early, before irq is set up. */ |
| 50 | notify_remote_via_evtchn(xen_start_info->console.domU.evtchn); |
| 51 | } |
| 52 | |
| 53 | static int write_console(uint32_t vtermno, const char *data, int len) |
| 54 | { |
| 55 | struct xencons_interface *intf = xencons_interface(); |
| 56 | XENCONS_RING_IDX cons, prod; |
| 57 | int sent = 0; |
| 58 | |
| 59 | cons = intf->out_cons; |
| 60 | prod = intf->out_prod; |
| 61 | mb(); /* update queue values before going on */ |
| 62 | BUG_ON((prod - cons) > sizeof(intf->out)); |
| 63 | |
| 64 | while ((sent < len) && ((prod - cons) < sizeof(intf->out))) |
| 65 | intf->out[MASK_XENCONS_IDX(prod++, intf->out)] = data[sent++]; |
| 66 | |
| 67 | wmb(); /* write ring before updating pointer */ |
| 68 | intf->out_prod = prod; |
| 69 | |
| 70 | notify_daemon(); |
| 71 | return sent; |
| 72 | } |
| 73 | |
| 74 | static int read_console(uint32_t vtermno, char *buf, int len) |
| 75 | { |
| 76 | struct xencons_interface *intf = xencons_interface(); |
| 77 | XENCONS_RING_IDX cons, prod; |
| 78 | int recv = 0; |
| 79 | |
| 80 | cons = intf->in_cons; |
| 81 | prod = intf->in_prod; |
| 82 | mb(); /* get pointers before reading ring */ |
| 83 | BUG_ON((prod - cons) > sizeof(intf->in)); |
| 84 | |
| 85 | while (cons != prod && recv < len) |
| 86 | buf[recv++] = intf->in[MASK_XENCONS_IDX(cons++, intf->in)]; |
| 87 | |
| 88 | mb(); /* read ring before consuming */ |
| 89 | intf->in_cons = cons; |
| 90 | |
| 91 | notify_daemon(); |
| 92 | return recv; |
| 93 | } |
| 94 | |
| 95 | static struct hv_ops hvc_ops = { |
| 96 | .get_chars = read_console, |
| 97 | .put_chars = write_console, |
| 98 | }; |
| 99 | |
| 100 | static int __init xen_init(void) |
| 101 | { |
| 102 | struct hvc_struct *hp; |
| 103 | |
| 104 | if (!is_running_on_xen()) |
| 105 | return 0; |
| 106 | |
| 107 | xencons_irq = bind_evtchn_to_irq(xen_start_info->console.domU.evtchn); |
| 108 | if (xencons_irq < 0) |
| 109 | xencons_irq = 0 /* NO_IRQ */; |
| 110 | hp = hvc_alloc(HVC_COOKIE, xencons_irq, &hvc_ops, 256); |
| 111 | if (IS_ERR(hp)) |
| 112 | return PTR_ERR(hp); |
| 113 | |
| 114 | hvc = hp; |
| 115 | return 0; |
| 116 | } |
| 117 | |
| 118 | static void __exit xen_fini(void) |
| 119 | { |
| 120 | if (hvc) |
| 121 | hvc_remove(hvc); |
| 122 | } |
| 123 | |
| 124 | static int xen_cons_init(void) |
| 125 | { |
| 126 | if (!is_running_on_xen()) |
| 127 | return 0; |
| 128 | |
| 129 | hvc_instantiate(HVC_COOKIE, 0, &hvc_ops); |
| 130 | return 0; |
| 131 | } |
| 132 | |
| 133 | module_init(xen_init); |
| 134 | module_exit(xen_fini); |
| 135 | console_initcall(xen_cons_init); |
| 136 | |
Jeremy Fitzhardinge | 0922abd | 2008-05-26 23:31:00 +0100 | [diff] [blame] | 137 | static void raw_console_write(const char *str, int len) |
| 138 | { |
| 139 | while(len > 0) { |
| 140 | int rc = HYPERVISOR_console_io(CONSOLEIO_write, len, (char *)str); |
| 141 | if (rc <= 0) |
| 142 | break; |
| 143 | |
| 144 | str += rc; |
| 145 | len -= rc; |
| 146 | } |
| 147 | } |
| 148 | |
| 149 | #ifdef CONFIG_EARLY_PRINTK |
Jeremy Fitzhardinge | b536b4b | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 150 | static void xenboot_write_console(struct console *console, const char *string, |
| 151 | unsigned len) |
| 152 | { |
| 153 | unsigned int linelen, off = 0; |
| 154 | const char *pos; |
| 155 | |
Jeremy Fitzhardinge | 0922abd | 2008-05-26 23:31:00 +0100 | [diff] [blame] | 156 | raw_console_write(string, len); |
| 157 | |
Jeremy Fitzhardinge | 83abc70 | 2008-05-26 23:31:12 +0100 | [diff] [blame] | 158 | write_console(0, "(early) ", 8); |
Jeremy Fitzhardinge | b536b4b | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 159 | while (off < len && NULL != (pos = strchr(string+off, '\n'))) { |
| 160 | linelen = pos-string+off; |
| 161 | if (off + linelen > len) |
| 162 | break; |
| 163 | write_console(0, string+off, linelen); |
| 164 | write_console(0, "\r\n", 2); |
| 165 | off += linelen + 1; |
| 166 | } |
| 167 | if (off < len) |
| 168 | write_console(0, string+off, len-off); |
| 169 | } |
| 170 | |
| 171 | struct console xenboot_console = { |
| 172 | .name = "xenboot", |
| 173 | .write = xenboot_write_console, |
Jeremy Fitzhardinge | 0922abd | 2008-05-26 23:31:00 +0100 | [diff] [blame] | 174 | .flags = CON_PRINTBUFFER | CON_BOOT | CON_ANYTIME, |
Jeremy Fitzhardinge | b536b4b | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 175 | }; |
Jeremy Fitzhardinge | 0922abd | 2008-05-26 23:31:00 +0100 | [diff] [blame] | 176 | #endif /* CONFIG_EARLY_PRINTK */ |
Jeremy Fitzhardinge | 0acf10d | 2008-05-26 23:30:59 +0100 | [diff] [blame] | 177 | |
| 178 | void xen_raw_console_write(const char *str) |
| 179 | { |
Jeremy Fitzhardinge | 0922abd | 2008-05-26 23:31:00 +0100 | [diff] [blame] | 180 | raw_console_write(str, strlen(str)); |
Jeremy Fitzhardinge | 0acf10d | 2008-05-26 23:30:59 +0100 | [diff] [blame] | 181 | } |
| 182 | |
| 183 | void xen_raw_printk(const char *fmt, ...) |
| 184 | { |
| 185 | static char buf[512]; |
| 186 | va_list ap; |
| 187 | |
| 188 | va_start(ap, fmt); |
| 189 | vsnprintf(buf, sizeof(buf), fmt, ap); |
| 190 | va_end(ap); |
| 191 | |
| 192 | xen_raw_console_write(buf); |
| 193 | } |