Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * drivers/s390/char/sclp.c |
| 3 | * core function to access sclp interface |
| 4 | * |
| 5 | * S390 version |
| 6 | * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation |
| 7 | * Author(s): Martin Peschke <mpeschke@de.ibm.com> |
| 8 | * Martin Schwidefsky <schwidefsky@de.ibm.com> |
| 9 | */ |
| 10 | |
| 11 | #include <linux/module.h> |
| 12 | #include <linux/err.h> |
| 13 | #include <linux/spinlock.h> |
| 14 | #include <linux/interrupt.h> |
| 15 | #include <linux/timer.h> |
| 16 | #include <linux/reboot.h> |
| 17 | #include <linux/jiffies.h> |
Peter Oberparleiter | b3d00c3 | 2007-04-27 16:01:51 +0200 | [diff] [blame] | 18 | #include <linux/init.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | #include <asm/types.h> |
| 20 | #include <asm/s390_ext.h> |
| 21 | |
| 22 | #include "sclp.h" |
| 23 | |
| 24 | #define SCLP_HEADER "sclp: " |
| 25 | |
| 26 | /* Structure for register_early_external_interrupt. */ |
| 27 | static ext_int_info_t ext_int_info_hwc; |
| 28 | |
| 29 | /* Lock to protect internal data consistency. */ |
| 30 | static DEFINE_SPINLOCK(sclp_lock); |
| 31 | |
Peter Oberparleiter | d082d3c | 2008-02-19 15:29:32 +0100 | [diff] [blame] | 32 | /* Mask of events that we can send to the sclp interface. */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | static sccb_mask_t sclp_receive_mask; |
| 34 | |
Peter Oberparleiter | d082d3c | 2008-02-19 15:29:32 +0100 | [diff] [blame] | 35 | /* Mask of events that we can receive from the sclp interface. */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | static sccb_mask_t sclp_send_mask; |
| 37 | |
| 38 | /* List of registered event listeners and senders. */ |
| 39 | static struct list_head sclp_reg_list; |
| 40 | |
| 41 | /* List of queued requests. */ |
| 42 | static struct list_head sclp_req_queue; |
| 43 | |
| 44 | /* Data for read and and init requests. */ |
| 45 | static struct sclp_req sclp_read_req; |
| 46 | static struct sclp_req sclp_init_req; |
| 47 | static char sclp_read_sccb[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE))); |
| 48 | static char sclp_init_sccb[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE))); |
| 49 | |
| 50 | /* Timer for request retries. */ |
| 51 | static struct timer_list sclp_request_timer; |
| 52 | |
| 53 | /* Internal state: is the driver initialized? */ |
| 54 | static volatile enum sclp_init_state_t { |
| 55 | sclp_init_state_uninitialized, |
| 56 | sclp_init_state_initializing, |
| 57 | sclp_init_state_initialized |
| 58 | } sclp_init_state = sclp_init_state_uninitialized; |
| 59 | |
| 60 | /* Internal state: is a request active at the sclp? */ |
| 61 | static volatile enum sclp_running_state_t { |
| 62 | sclp_running_state_idle, |
Peter Oberparleiter | dbd8ae6 | 2007-02-05 21:17:00 +0100 | [diff] [blame] | 63 | sclp_running_state_running, |
| 64 | sclp_running_state_reset_pending |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 65 | } sclp_running_state = sclp_running_state_idle; |
| 66 | |
| 67 | /* Internal state: is a read request pending? */ |
| 68 | static volatile enum sclp_reading_state_t { |
| 69 | sclp_reading_state_idle, |
| 70 | sclp_reading_state_reading |
| 71 | } sclp_reading_state = sclp_reading_state_idle; |
| 72 | |
| 73 | /* Internal state: is the driver currently serving requests? */ |
| 74 | static volatile enum sclp_activation_state_t { |
| 75 | sclp_activation_state_active, |
| 76 | sclp_activation_state_deactivating, |
| 77 | sclp_activation_state_inactive, |
| 78 | sclp_activation_state_activating |
| 79 | } sclp_activation_state = sclp_activation_state_active; |
| 80 | |
| 81 | /* Internal state: is an init mask request pending? */ |
| 82 | static volatile enum sclp_mask_state_t { |
| 83 | sclp_mask_state_idle, |
| 84 | sclp_mask_state_initializing |
| 85 | } sclp_mask_state = sclp_mask_state_idle; |
| 86 | |
| 87 | /* Maximum retry counts */ |
| 88 | #define SCLP_INIT_RETRY 3 |
| 89 | #define SCLP_MASK_RETRY 3 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 90 | |
| 91 | /* Timeout intervals in seconds.*/ |
Peter Oberparleiter | 25fab9e | 2006-02-11 17:55:59 -0800 | [diff] [blame] | 92 | #define SCLP_BUSY_INTERVAL 10 |
Peter Oberparleiter | dbd8ae6 | 2007-02-05 21:17:00 +0100 | [diff] [blame] | 93 | #define SCLP_RETRY_INTERVAL 30 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | |
| 95 | static void sclp_process_queue(void); |
Heiko Carstens | 364c855 | 2007-10-12 16:11:35 +0200 | [diff] [blame] | 96 | static void __sclp_make_read_req(void); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 97 | static int sclp_init_mask(int calculate); |
| 98 | static int sclp_init(void); |
| 99 | |
| 100 | /* Perform service call. Return 0 on success, non-zero otherwise. */ |
Heiko Carstens | ab14de6 | 2007-02-05 21:18:37 +0100 | [diff] [blame] | 101 | int |
| 102 | sclp_service_call(sclp_cmdw_t command, void *sccb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 103 | { |
| 104 | int cc; |
| 105 | |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 106 | asm volatile( |
| 107 | " .insn rre,0xb2200000,%1,%2\n" /* servc %1,%2 */ |
| 108 | " ipm %0\n" |
| 109 | " srl %0,28" |
| 110 | : "=&d" (cc) : "d" (command), "a" (__pa(sccb)) |
| 111 | : "cc", "memory"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | if (cc == 3) |
| 113 | return -EIO; |
| 114 | if (cc == 2) |
| 115 | return -EBUSY; |
| 116 | return 0; |
| 117 | } |
| 118 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | |
Peter Oberparleiter | dbd8ae6 | 2007-02-05 21:17:00 +0100 | [diff] [blame] | 120 | static void |
| 121 | __sclp_queue_read_req(void) |
| 122 | { |
| 123 | if (sclp_reading_state == sclp_reading_state_idle) { |
| 124 | sclp_reading_state = sclp_reading_state_reading; |
| 125 | __sclp_make_read_req(); |
| 126 | /* Add request to head of queue */ |
| 127 | list_add(&sclp_read_req.list, &sclp_req_queue); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 128 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 129 | } |
| 130 | |
| 131 | /* Set up request retry timer. Called while sclp_lock is locked. */ |
| 132 | static inline void |
| 133 | __sclp_set_request_timer(unsigned long time, void (*function)(unsigned long), |
| 134 | unsigned long data) |
| 135 | { |
| 136 | del_timer(&sclp_request_timer); |
| 137 | sclp_request_timer.function = function; |
| 138 | sclp_request_timer.data = data; |
| 139 | sclp_request_timer.expires = jiffies + time; |
| 140 | add_timer(&sclp_request_timer); |
| 141 | } |
| 142 | |
Peter Oberparleiter | dbd8ae6 | 2007-02-05 21:17:00 +0100 | [diff] [blame] | 143 | /* Request timeout handler. Restart the request queue. If DATA is non-zero, |
| 144 | * force restart of running request. */ |
| 145 | static void |
| 146 | sclp_request_timeout(unsigned long data) |
| 147 | { |
| 148 | unsigned long flags; |
| 149 | |
| 150 | spin_lock_irqsave(&sclp_lock, flags); |
| 151 | if (data) { |
| 152 | if (sclp_running_state == sclp_running_state_running) { |
| 153 | /* Break running state and queue NOP read event request |
| 154 | * to get a defined interface state. */ |
| 155 | __sclp_queue_read_req(); |
| 156 | sclp_running_state = sclp_running_state_idle; |
| 157 | } |
| 158 | } else { |
| 159 | __sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ, |
| 160 | sclp_request_timeout, 0); |
| 161 | } |
| 162 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 163 | sclp_process_queue(); |
| 164 | } |
| 165 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 166 | /* Try to start a request. Return zero if the request was successfully |
| 167 | * started or if it will be started at a later time. Return non-zero otherwise. |
| 168 | * Called while sclp_lock is locked. */ |
| 169 | static int |
| 170 | __sclp_start_request(struct sclp_req *req) |
| 171 | { |
| 172 | int rc; |
| 173 | |
| 174 | if (sclp_running_state != sclp_running_state_idle) |
| 175 | return 0; |
| 176 | del_timer(&sclp_request_timer); |
Heiko Carstens | ab14de6 | 2007-02-05 21:18:37 +0100 | [diff] [blame] | 177 | rc = sclp_service_call(req->command, req->sccb); |
Peter Oberparleiter | 25fab9e | 2006-02-11 17:55:59 -0800 | [diff] [blame] | 178 | req->start_count++; |
| 179 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 180 | if (rc == 0) { |
| 181 | /* Sucessfully started request */ |
| 182 | req->status = SCLP_REQ_RUNNING; |
| 183 | sclp_running_state = sclp_running_state_running; |
| 184 | __sclp_set_request_timer(SCLP_RETRY_INTERVAL * HZ, |
| 185 | sclp_request_timeout, 1); |
| 186 | return 0; |
| 187 | } else if (rc == -EBUSY) { |
| 188 | /* Try again later */ |
| 189 | __sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ, |
| 190 | sclp_request_timeout, 0); |
| 191 | return 0; |
| 192 | } |
| 193 | /* Request failed */ |
| 194 | req->status = SCLP_REQ_FAILED; |
| 195 | return rc; |
| 196 | } |
| 197 | |
| 198 | /* Try to start queued requests. */ |
| 199 | static void |
| 200 | sclp_process_queue(void) |
| 201 | { |
| 202 | struct sclp_req *req; |
| 203 | int rc; |
| 204 | unsigned long flags; |
| 205 | |
| 206 | spin_lock_irqsave(&sclp_lock, flags); |
| 207 | if (sclp_running_state != sclp_running_state_idle) { |
| 208 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 209 | return; |
| 210 | } |
| 211 | del_timer(&sclp_request_timer); |
| 212 | while (!list_empty(&sclp_req_queue)) { |
| 213 | req = list_entry(sclp_req_queue.next, struct sclp_req, list); |
| 214 | rc = __sclp_start_request(req); |
| 215 | if (rc == 0) |
| 216 | break; |
Peter Oberparleiter | dbd8ae6 | 2007-02-05 21:17:00 +0100 | [diff] [blame] | 217 | /* Request failed */ |
| 218 | if (req->start_count > 1) { |
| 219 | /* Cannot abort already submitted request - could still |
| 220 | * be active at the SCLP */ |
| 221 | __sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ, |
| 222 | sclp_request_timeout, 0); |
| 223 | break; |
| 224 | } |
| 225 | /* Post-processing for aborted request */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | list_del(&req->list); |
| 227 | if (req->callback) { |
| 228 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 229 | req->callback(req, req->callback_data); |
| 230 | spin_lock_irqsave(&sclp_lock, flags); |
| 231 | } |
| 232 | } |
| 233 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 234 | } |
| 235 | |
| 236 | /* Queue a new request. Return zero on success, non-zero otherwise. */ |
| 237 | int |
| 238 | sclp_add_request(struct sclp_req *req) |
| 239 | { |
| 240 | unsigned long flags; |
| 241 | int rc; |
| 242 | |
| 243 | spin_lock_irqsave(&sclp_lock, flags); |
| 244 | if ((sclp_init_state != sclp_init_state_initialized || |
| 245 | sclp_activation_state != sclp_activation_state_active) && |
| 246 | req != &sclp_init_req) { |
| 247 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 248 | return -EIO; |
| 249 | } |
| 250 | req->status = SCLP_REQ_QUEUED; |
| 251 | req->start_count = 0; |
| 252 | list_add_tail(&req->list, &sclp_req_queue); |
| 253 | rc = 0; |
| 254 | /* Start if request is first in list */ |
Peter Oberparleiter | dbd8ae6 | 2007-02-05 21:17:00 +0100 | [diff] [blame] | 255 | if (sclp_running_state == sclp_running_state_idle && |
| 256 | req->list.prev == &sclp_req_queue) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 257 | rc = __sclp_start_request(req); |
| 258 | if (rc) |
| 259 | list_del(&req->list); |
| 260 | } |
| 261 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 262 | return rc; |
| 263 | } |
| 264 | |
| 265 | EXPORT_SYMBOL(sclp_add_request); |
| 266 | |
| 267 | /* Dispatch events found in request buffer to registered listeners. Return 0 |
| 268 | * if all events were dispatched, non-zero otherwise. */ |
| 269 | static int |
| 270 | sclp_dispatch_evbufs(struct sccb_header *sccb) |
| 271 | { |
| 272 | unsigned long flags; |
| 273 | struct evbuf_header *evbuf; |
| 274 | struct list_head *l; |
| 275 | struct sclp_register *reg; |
| 276 | int offset; |
| 277 | int rc; |
| 278 | |
| 279 | spin_lock_irqsave(&sclp_lock, flags); |
| 280 | rc = 0; |
| 281 | for (offset = sizeof(struct sccb_header); offset < sccb->length; |
| 282 | offset += evbuf->length) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 283 | evbuf = (struct evbuf_header *) ((addr_t) sccb + offset); |
Peter Oberparleiter | e2e5a0f | 2009-02-19 15:18:59 +0100 | [diff] [blame^] | 284 | /* Check for malformed hardware response */ |
| 285 | if (evbuf->length == 0) |
| 286 | break; |
| 287 | /* Search for event handler */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 288 | reg = NULL; |
| 289 | list_for_each(l, &sclp_reg_list) { |
| 290 | reg = list_entry(l, struct sclp_register, list); |
| 291 | if (reg->receive_mask & (1 << (32 - evbuf->type))) |
| 292 | break; |
| 293 | else |
| 294 | reg = NULL; |
| 295 | } |
| 296 | if (reg && reg->receiver_fn) { |
| 297 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 298 | reg->receiver_fn(evbuf); |
| 299 | spin_lock_irqsave(&sclp_lock, flags); |
| 300 | } else if (reg == NULL) |
| 301 | rc = -ENOSYS; |
| 302 | } |
| 303 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 304 | return rc; |
| 305 | } |
| 306 | |
| 307 | /* Read event data request callback. */ |
| 308 | static void |
| 309 | sclp_read_cb(struct sclp_req *req, void *data) |
| 310 | { |
| 311 | unsigned long flags; |
| 312 | struct sccb_header *sccb; |
| 313 | |
| 314 | sccb = (struct sccb_header *) req->sccb; |
| 315 | if (req->status == SCLP_REQ_DONE && (sccb->response_code == 0x20 || |
| 316 | sccb->response_code == 0x220)) |
| 317 | sclp_dispatch_evbufs(sccb); |
| 318 | spin_lock_irqsave(&sclp_lock, flags); |
| 319 | sclp_reading_state = sclp_reading_state_idle; |
| 320 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 321 | } |
| 322 | |
| 323 | /* Prepare read event data request. Called while sclp_lock is locked. */ |
Heiko Carstens | 364c855 | 2007-10-12 16:11:35 +0200 | [diff] [blame] | 324 | static void __sclp_make_read_req(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 325 | { |
| 326 | struct sccb_header *sccb; |
| 327 | |
| 328 | sccb = (struct sccb_header *) sclp_read_sccb; |
| 329 | clear_page(sccb); |
| 330 | memset(&sclp_read_req, 0, sizeof(struct sclp_req)); |
Heiko Carstens | ab14de6 | 2007-02-05 21:18:37 +0100 | [diff] [blame] | 331 | sclp_read_req.command = SCLP_CMDW_READ_EVENT_DATA; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 332 | sclp_read_req.status = SCLP_REQ_QUEUED; |
| 333 | sclp_read_req.start_count = 0; |
| 334 | sclp_read_req.callback = sclp_read_cb; |
| 335 | sclp_read_req.sccb = sccb; |
| 336 | sccb->length = PAGE_SIZE; |
| 337 | sccb->function_code = 0; |
| 338 | sccb->control_mask[2] = 0x80; |
| 339 | } |
| 340 | |
| 341 | /* Search request list for request with matching sccb. Return request if found, |
| 342 | * NULL otherwise. Called while sclp_lock is locked. */ |
| 343 | static inline struct sclp_req * |
| 344 | __sclp_find_req(u32 sccb) |
| 345 | { |
| 346 | struct list_head *l; |
| 347 | struct sclp_req *req; |
| 348 | |
| 349 | list_for_each(l, &sclp_req_queue) { |
| 350 | req = list_entry(l, struct sclp_req, list); |
| 351 | if (sccb == (u32) (addr_t) req->sccb) |
| 352 | return req; |
| 353 | } |
| 354 | return NULL; |
| 355 | } |
| 356 | |
| 357 | /* Handler for external interruption. Perform request post-processing. |
| 358 | * Prepare read event data request if necessary. Start processing of next |
| 359 | * request on queue. */ |
| 360 | static void |
Heiko Carstens | 5a489b9 | 2006-10-06 16:38:35 +0200 | [diff] [blame] | 361 | sclp_interrupt_handler(__u16 code) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 362 | { |
| 363 | struct sclp_req *req; |
| 364 | u32 finished_sccb; |
| 365 | u32 evbuf_pending; |
| 366 | |
| 367 | spin_lock(&sclp_lock); |
| 368 | finished_sccb = S390_lowcore.ext_params & 0xfffffff8; |
| 369 | evbuf_pending = S390_lowcore.ext_params & 0x3; |
| 370 | if (finished_sccb) { |
Peter Oberparleiter | dbd8ae6 | 2007-02-05 21:17:00 +0100 | [diff] [blame] | 371 | del_timer(&sclp_request_timer); |
| 372 | sclp_running_state = sclp_running_state_reset_pending; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 373 | req = __sclp_find_req(finished_sccb); |
| 374 | if (req) { |
| 375 | /* Request post-processing */ |
| 376 | list_del(&req->list); |
| 377 | req->status = SCLP_REQ_DONE; |
| 378 | if (req->callback) { |
| 379 | spin_unlock(&sclp_lock); |
| 380 | req->callback(req, req->callback_data); |
| 381 | spin_lock(&sclp_lock); |
| 382 | } |
| 383 | } |
| 384 | sclp_running_state = sclp_running_state_idle; |
| 385 | } |
Peter Oberparleiter | d082d3c | 2008-02-19 15:29:32 +0100 | [diff] [blame] | 386 | if (evbuf_pending && |
Peter Oberparleiter | dbd8ae6 | 2007-02-05 21:17:00 +0100 | [diff] [blame] | 387 | sclp_activation_state == sclp_activation_state_active) |
| 388 | __sclp_queue_read_req(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 389 | spin_unlock(&sclp_lock); |
| 390 | sclp_process_queue(); |
| 391 | } |
| 392 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 393 | /* Convert interval in jiffies to TOD ticks. */ |
| 394 | static inline u64 |
| 395 | sclp_tod_from_jiffies(unsigned long jiffies) |
| 396 | { |
| 397 | return (u64) (jiffies / HZ) << 32; |
| 398 | } |
| 399 | |
| 400 | /* Wait until a currently running request finished. Note: while this function |
| 401 | * is running, no timers are served on the calling CPU. */ |
| 402 | void |
| 403 | sclp_sync_wait(void) |
| 404 | { |
Heiko Carstens | 934b285 | 2008-08-01 16:39:11 +0200 | [diff] [blame] | 405 | unsigned long long old_tick; |
Heiko Carstens | 1f194a4 | 2006-07-03 00:24:46 -0700 | [diff] [blame] | 406 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 407 | unsigned long cr0, cr0_sync; |
| 408 | u64 timeout; |
Heiko Carstens | c59d744 | 2007-02-05 21:17:16 +0100 | [diff] [blame] | 409 | int irq_context; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 410 | |
| 411 | /* We'll be disabling timer interrupts, so we need a custom timeout |
| 412 | * mechanism */ |
| 413 | timeout = 0; |
| 414 | if (timer_pending(&sclp_request_timer)) { |
| 415 | /* Get timeout TOD value */ |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 416 | timeout = get_clock() + |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 417 | sclp_tod_from_jiffies(sclp_request_timer.expires - |
| 418 | jiffies); |
| 419 | } |
Heiko Carstens | 1f194a4 | 2006-07-03 00:24:46 -0700 | [diff] [blame] | 420 | local_irq_save(flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 421 | /* Prevent bottom half from executing once we force interrupts open */ |
Heiko Carstens | c59d744 | 2007-02-05 21:17:16 +0100 | [diff] [blame] | 422 | irq_context = in_interrupt(); |
| 423 | if (!irq_context) |
| 424 | local_bh_disable(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 425 | /* Enable service-signal interruption, disable timer interrupts */ |
Heiko Carstens | 934b285 | 2008-08-01 16:39:11 +0200 | [diff] [blame] | 426 | old_tick = local_tick_disable(); |
Heiko Carstens | 1f194a4 | 2006-07-03 00:24:46 -0700 | [diff] [blame] | 427 | trace_hardirqs_on(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 428 | __ctl_store(cr0, 0, 0); |
| 429 | cr0_sync = cr0; |
Heiko Carstens | 934b285 | 2008-08-01 16:39:11 +0200 | [diff] [blame] | 430 | cr0_sync &= 0xffff00a0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 431 | cr0_sync |= 0x00000200; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 432 | __ctl_load(cr0_sync, 0, 0); |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 433 | __raw_local_irq_stosm(0x01); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 434 | /* Loop until driver state indicates finished request */ |
| 435 | while (sclp_running_state != sclp_running_state_idle) { |
| 436 | /* Check for expired request timer */ |
| 437 | if (timer_pending(&sclp_request_timer) && |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 438 | get_clock() > timeout && |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 439 | del_timer(&sclp_request_timer)) |
| 440 | sclp_request_timer.function(sclp_request_timer.data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 441 | cpu_relax(); |
| 442 | } |
Heiko Carstens | 1f194a4 | 2006-07-03 00:24:46 -0700 | [diff] [blame] | 443 | local_irq_disable(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 444 | __ctl_load(cr0, 0, 0); |
Heiko Carstens | c59d744 | 2007-02-05 21:17:16 +0100 | [diff] [blame] | 445 | if (!irq_context) |
| 446 | _local_bh_enable(); |
Heiko Carstens | 934b285 | 2008-08-01 16:39:11 +0200 | [diff] [blame] | 447 | local_tick_enable(old_tick); |
Heiko Carstens | 1f194a4 | 2006-07-03 00:24:46 -0700 | [diff] [blame] | 448 | local_irq_restore(flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 449 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 450 | EXPORT_SYMBOL(sclp_sync_wait); |
| 451 | |
| 452 | /* Dispatch changes in send and receive mask to registered listeners. */ |
Heiko Carstens | 4d284ca | 2007-02-05 21:18:53 +0100 | [diff] [blame] | 453 | static void |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | sclp_dispatch_state_change(void) |
| 455 | { |
| 456 | struct list_head *l; |
| 457 | struct sclp_register *reg; |
| 458 | unsigned long flags; |
| 459 | sccb_mask_t receive_mask; |
| 460 | sccb_mask_t send_mask; |
| 461 | |
| 462 | do { |
| 463 | spin_lock_irqsave(&sclp_lock, flags); |
| 464 | reg = NULL; |
| 465 | list_for_each(l, &sclp_reg_list) { |
| 466 | reg = list_entry(l, struct sclp_register, list); |
Peter Oberparleiter | d082d3c | 2008-02-19 15:29:32 +0100 | [diff] [blame] | 467 | receive_mask = reg->send_mask & sclp_receive_mask; |
| 468 | send_mask = reg->receive_mask & sclp_send_mask; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 469 | if (reg->sclp_receive_mask != receive_mask || |
| 470 | reg->sclp_send_mask != send_mask) { |
| 471 | reg->sclp_receive_mask = receive_mask; |
| 472 | reg->sclp_send_mask = send_mask; |
| 473 | break; |
| 474 | } else |
| 475 | reg = NULL; |
| 476 | } |
| 477 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 478 | if (reg && reg->state_change_fn) |
| 479 | reg->state_change_fn(reg); |
| 480 | } while (reg); |
| 481 | } |
| 482 | |
| 483 | struct sclp_statechangebuf { |
| 484 | struct evbuf_header header; |
| 485 | u8 validity_sclp_active_facility_mask : 1; |
| 486 | u8 validity_sclp_receive_mask : 1; |
| 487 | u8 validity_sclp_send_mask : 1; |
| 488 | u8 validity_read_data_function_mask : 1; |
| 489 | u16 _zeros : 12; |
| 490 | u16 mask_length; |
| 491 | u64 sclp_active_facility_mask; |
| 492 | sccb_mask_t sclp_receive_mask; |
| 493 | sccb_mask_t sclp_send_mask; |
| 494 | u32 read_data_function_mask; |
| 495 | } __attribute__((packed)); |
| 496 | |
| 497 | |
| 498 | /* State change event callback. Inform listeners of changes. */ |
| 499 | static void |
| 500 | sclp_state_change_cb(struct evbuf_header *evbuf) |
| 501 | { |
| 502 | unsigned long flags; |
| 503 | struct sclp_statechangebuf *scbuf; |
| 504 | |
| 505 | scbuf = (struct sclp_statechangebuf *) evbuf; |
| 506 | if (scbuf->mask_length != sizeof(sccb_mask_t)) |
| 507 | return; |
| 508 | spin_lock_irqsave(&sclp_lock, flags); |
| 509 | if (scbuf->validity_sclp_receive_mask) |
| 510 | sclp_receive_mask = scbuf->sclp_receive_mask; |
| 511 | if (scbuf->validity_sclp_send_mask) |
| 512 | sclp_send_mask = scbuf->sclp_send_mask; |
| 513 | spin_unlock_irqrestore(&sclp_lock, flags); |
Heiko Carstens | 887d935 | 2008-07-14 09:57:26 +0200 | [diff] [blame] | 514 | if (scbuf->validity_sclp_active_facility_mask) |
| 515 | sclp_facilities = scbuf->sclp_active_facility_mask; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 516 | sclp_dispatch_state_change(); |
| 517 | } |
| 518 | |
| 519 | static struct sclp_register sclp_state_change_event = { |
Stefan Haberland | 6d4740c | 2007-04-27 16:01:53 +0200 | [diff] [blame] | 520 | .receive_mask = EVTYP_STATECHANGE_MASK, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 521 | .receiver_fn = sclp_state_change_cb |
| 522 | }; |
| 523 | |
| 524 | /* Calculate receive and send mask of currently registered listeners. |
| 525 | * Called while sclp_lock is locked. */ |
| 526 | static inline void |
| 527 | __sclp_get_mask(sccb_mask_t *receive_mask, sccb_mask_t *send_mask) |
| 528 | { |
| 529 | struct list_head *l; |
| 530 | struct sclp_register *t; |
| 531 | |
| 532 | *receive_mask = 0; |
| 533 | *send_mask = 0; |
| 534 | list_for_each(l, &sclp_reg_list) { |
| 535 | t = list_entry(l, struct sclp_register, list); |
| 536 | *receive_mask |= t->receive_mask; |
| 537 | *send_mask |= t->send_mask; |
| 538 | } |
| 539 | } |
| 540 | |
| 541 | /* Register event listener. Return 0 on success, non-zero otherwise. */ |
| 542 | int |
| 543 | sclp_register(struct sclp_register *reg) |
| 544 | { |
| 545 | unsigned long flags; |
| 546 | sccb_mask_t receive_mask; |
| 547 | sccb_mask_t send_mask; |
| 548 | int rc; |
| 549 | |
| 550 | rc = sclp_init(); |
| 551 | if (rc) |
| 552 | return rc; |
| 553 | spin_lock_irqsave(&sclp_lock, flags); |
| 554 | /* Check event mask for collisions */ |
| 555 | __sclp_get_mask(&receive_mask, &send_mask); |
| 556 | if (reg->receive_mask & receive_mask || reg->send_mask & send_mask) { |
| 557 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 558 | return -EBUSY; |
| 559 | } |
| 560 | /* Trigger initial state change callback */ |
| 561 | reg->sclp_receive_mask = 0; |
| 562 | reg->sclp_send_mask = 0; |
| 563 | list_add(®->list, &sclp_reg_list); |
| 564 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 565 | rc = sclp_init_mask(1); |
| 566 | if (rc) { |
| 567 | spin_lock_irqsave(&sclp_lock, flags); |
| 568 | list_del(®->list); |
| 569 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 570 | } |
| 571 | return rc; |
| 572 | } |
| 573 | |
| 574 | EXPORT_SYMBOL(sclp_register); |
| 575 | |
| 576 | /* Unregister event listener. */ |
| 577 | void |
| 578 | sclp_unregister(struct sclp_register *reg) |
| 579 | { |
| 580 | unsigned long flags; |
| 581 | |
| 582 | spin_lock_irqsave(&sclp_lock, flags); |
| 583 | list_del(®->list); |
| 584 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 585 | sclp_init_mask(1); |
| 586 | } |
| 587 | |
| 588 | EXPORT_SYMBOL(sclp_unregister); |
| 589 | |
| 590 | /* Remove event buffers which are marked processed. Return the number of |
| 591 | * remaining event buffers. */ |
| 592 | int |
| 593 | sclp_remove_processed(struct sccb_header *sccb) |
| 594 | { |
| 595 | struct evbuf_header *evbuf; |
| 596 | int unprocessed; |
| 597 | u16 remaining; |
| 598 | |
| 599 | evbuf = (struct evbuf_header *) (sccb + 1); |
| 600 | unprocessed = 0; |
| 601 | remaining = sccb->length - sizeof(struct sccb_header); |
| 602 | while (remaining > 0) { |
| 603 | remaining -= evbuf->length; |
| 604 | if (evbuf->flags & 0x80) { |
| 605 | sccb->length -= evbuf->length; |
| 606 | memcpy(evbuf, (void *) ((addr_t) evbuf + evbuf->length), |
| 607 | remaining); |
| 608 | } else { |
| 609 | unprocessed++; |
| 610 | evbuf = (struct evbuf_header *) |
| 611 | ((addr_t) evbuf + evbuf->length); |
| 612 | } |
| 613 | } |
| 614 | return unprocessed; |
| 615 | } |
| 616 | |
| 617 | EXPORT_SYMBOL(sclp_remove_processed); |
| 618 | |
| 619 | struct init_sccb { |
| 620 | struct sccb_header header; |
| 621 | u16 _reserved; |
| 622 | u16 mask_length; |
| 623 | sccb_mask_t receive_mask; |
| 624 | sccb_mask_t send_mask; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 625 | sccb_mask_t sclp_receive_mask; |
Peter Oberparleiter | d082d3c | 2008-02-19 15:29:32 +0100 | [diff] [blame] | 626 | sccb_mask_t sclp_send_mask; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 627 | } __attribute__((packed)); |
| 628 | |
| 629 | /* Prepare init mask request. Called while sclp_lock is locked. */ |
| 630 | static inline void |
| 631 | __sclp_make_init_req(u32 receive_mask, u32 send_mask) |
| 632 | { |
| 633 | struct init_sccb *sccb; |
| 634 | |
| 635 | sccb = (struct init_sccb *) sclp_init_sccb; |
| 636 | clear_page(sccb); |
| 637 | memset(&sclp_init_req, 0, sizeof(struct sclp_req)); |
Heiko Carstens | ab14de6 | 2007-02-05 21:18:37 +0100 | [diff] [blame] | 638 | sclp_init_req.command = SCLP_CMDW_WRITE_EVENT_MASK; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 639 | sclp_init_req.status = SCLP_REQ_FILLED; |
| 640 | sclp_init_req.start_count = 0; |
| 641 | sclp_init_req.callback = NULL; |
| 642 | sclp_init_req.callback_data = NULL; |
| 643 | sclp_init_req.sccb = sccb; |
| 644 | sccb->header.length = sizeof(struct init_sccb); |
| 645 | sccb->mask_length = sizeof(sccb_mask_t); |
| 646 | sccb->receive_mask = receive_mask; |
| 647 | sccb->send_mask = send_mask; |
| 648 | sccb->sclp_receive_mask = 0; |
| 649 | sccb->sclp_send_mask = 0; |
| 650 | } |
| 651 | |
| 652 | /* Start init mask request. If calculate is non-zero, calculate the mask as |
| 653 | * requested by registered listeners. Use zero mask otherwise. Return 0 on |
| 654 | * success, non-zero otherwise. */ |
| 655 | static int |
| 656 | sclp_init_mask(int calculate) |
| 657 | { |
| 658 | unsigned long flags; |
| 659 | struct init_sccb *sccb = (struct init_sccb *) sclp_init_sccb; |
| 660 | sccb_mask_t receive_mask; |
| 661 | sccb_mask_t send_mask; |
| 662 | int retry; |
| 663 | int rc; |
| 664 | unsigned long wait; |
| 665 | |
| 666 | spin_lock_irqsave(&sclp_lock, flags); |
| 667 | /* Check if interface is in appropriate state */ |
| 668 | if (sclp_mask_state != sclp_mask_state_idle) { |
| 669 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 670 | return -EBUSY; |
| 671 | } |
| 672 | if (sclp_activation_state == sclp_activation_state_inactive) { |
| 673 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 674 | return -EINVAL; |
| 675 | } |
| 676 | sclp_mask_state = sclp_mask_state_initializing; |
| 677 | /* Determine mask */ |
| 678 | if (calculate) |
| 679 | __sclp_get_mask(&receive_mask, &send_mask); |
| 680 | else { |
| 681 | receive_mask = 0; |
| 682 | send_mask = 0; |
| 683 | } |
| 684 | rc = -EIO; |
| 685 | for (retry = 0; retry <= SCLP_MASK_RETRY; retry++) { |
| 686 | /* Prepare request */ |
| 687 | __sclp_make_init_req(receive_mask, send_mask); |
| 688 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 689 | if (sclp_add_request(&sclp_init_req)) { |
| 690 | /* Try again later */ |
| 691 | wait = jiffies + SCLP_BUSY_INTERVAL * HZ; |
| 692 | while (time_before(jiffies, wait)) |
| 693 | sclp_sync_wait(); |
| 694 | spin_lock_irqsave(&sclp_lock, flags); |
| 695 | continue; |
| 696 | } |
| 697 | while (sclp_init_req.status != SCLP_REQ_DONE && |
| 698 | sclp_init_req.status != SCLP_REQ_FAILED) |
| 699 | sclp_sync_wait(); |
| 700 | spin_lock_irqsave(&sclp_lock, flags); |
| 701 | if (sclp_init_req.status == SCLP_REQ_DONE && |
| 702 | sccb->header.response_code == 0x20) { |
| 703 | /* Successful request */ |
| 704 | if (calculate) { |
| 705 | sclp_receive_mask = sccb->sclp_receive_mask; |
| 706 | sclp_send_mask = sccb->sclp_send_mask; |
| 707 | } else { |
| 708 | sclp_receive_mask = 0; |
| 709 | sclp_send_mask = 0; |
| 710 | } |
| 711 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 712 | sclp_dispatch_state_change(); |
| 713 | spin_lock_irqsave(&sclp_lock, flags); |
| 714 | rc = 0; |
| 715 | break; |
| 716 | } |
| 717 | } |
| 718 | sclp_mask_state = sclp_mask_state_idle; |
| 719 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 720 | return rc; |
| 721 | } |
| 722 | |
| 723 | /* Deactivate SCLP interface. On success, new requests will be rejected, |
| 724 | * events will no longer be dispatched. Return 0 on success, non-zero |
| 725 | * otherwise. */ |
| 726 | int |
| 727 | sclp_deactivate(void) |
| 728 | { |
| 729 | unsigned long flags; |
| 730 | int rc; |
| 731 | |
| 732 | spin_lock_irqsave(&sclp_lock, flags); |
| 733 | /* Deactivate can only be called when active */ |
| 734 | if (sclp_activation_state != sclp_activation_state_active) { |
| 735 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 736 | return -EINVAL; |
| 737 | } |
| 738 | sclp_activation_state = sclp_activation_state_deactivating; |
| 739 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 740 | rc = sclp_init_mask(0); |
| 741 | spin_lock_irqsave(&sclp_lock, flags); |
| 742 | if (rc == 0) |
| 743 | sclp_activation_state = sclp_activation_state_inactive; |
| 744 | else |
| 745 | sclp_activation_state = sclp_activation_state_active; |
| 746 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 747 | return rc; |
| 748 | } |
| 749 | |
| 750 | EXPORT_SYMBOL(sclp_deactivate); |
| 751 | |
| 752 | /* Reactivate SCLP interface after sclp_deactivate. On success, new |
| 753 | * requests will be accepted, events will be dispatched again. Return 0 on |
| 754 | * success, non-zero otherwise. */ |
| 755 | int |
| 756 | sclp_reactivate(void) |
| 757 | { |
| 758 | unsigned long flags; |
| 759 | int rc; |
| 760 | |
| 761 | spin_lock_irqsave(&sclp_lock, flags); |
| 762 | /* Reactivate can only be called when inactive */ |
| 763 | if (sclp_activation_state != sclp_activation_state_inactive) { |
| 764 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 765 | return -EINVAL; |
| 766 | } |
| 767 | sclp_activation_state = sclp_activation_state_activating; |
| 768 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 769 | rc = sclp_init_mask(1); |
| 770 | spin_lock_irqsave(&sclp_lock, flags); |
| 771 | if (rc == 0) |
| 772 | sclp_activation_state = sclp_activation_state_active; |
| 773 | else |
| 774 | sclp_activation_state = sclp_activation_state_inactive; |
| 775 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 776 | return rc; |
| 777 | } |
| 778 | |
| 779 | EXPORT_SYMBOL(sclp_reactivate); |
| 780 | |
| 781 | /* Handler for external interruption used during initialization. Modify |
| 782 | * request state to done. */ |
| 783 | static void |
Heiko Carstens | 5a489b9 | 2006-10-06 16:38:35 +0200 | [diff] [blame] | 784 | sclp_check_handler(__u16 code) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 785 | { |
| 786 | u32 finished_sccb; |
| 787 | |
| 788 | finished_sccb = S390_lowcore.ext_params & 0xfffffff8; |
| 789 | /* Is this the interrupt we are waiting for? */ |
| 790 | if (finished_sccb == 0) |
| 791 | return; |
Martin Schwidefsky | a12c53f | 2008-07-14 09:59:28 +0200 | [diff] [blame] | 792 | if (finished_sccb != (u32) (addr_t) sclp_init_sccb) |
| 793 | panic("sclp: unsolicited interrupt for buffer at 0x%x\n", |
| 794 | finished_sccb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 795 | spin_lock(&sclp_lock); |
| 796 | if (sclp_running_state == sclp_running_state_running) { |
| 797 | sclp_init_req.status = SCLP_REQ_DONE; |
| 798 | sclp_running_state = sclp_running_state_idle; |
| 799 | } |
| 800 | spin_unlock(&sclp_lock); |
| 801 | } |
| 802 | |
| 803 | /* Initial init mask request timed out. Modify request state to failed. */ |
| 804 | static void |
| 805 | sclp_check_timeout(unsigned long data) |
| 806 | { |
| 807 | unsigned long flags; |
| 808 | |
| 809 | spin_lock_irqsave(&sclp_lock, flags); |
| 810 | if (sclp_running_state == sclp_running_state_running) { |
| 811 | sclp_init_req.status = SCLP_REQ_FAILED; |
| 812 | sclp_running_state = sclp_running_state_idle; |
| 813 | } |
| 814 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 815 | } |
| 816 | |
| 817 | /* Perform a check of the SCLP interface. Return zero if the interface is |
| 818 | * available and there are no pending requests from a previous instance. |
| 819 | * Return non-zero otherwise. */ |
| 820 | static int |
| 821 | sclp_check_interface(void) |
| 822 | { |
| 823 | struct init_sccb *sccb; |
| 824 | unsigned long flags; |
| 825 | int retry; |
| 826 | int rc; |
| 827 | |
| 828 | spin_lock_irqsave(&sclp_lock, flags); |
| 829 | /* Prepare init mask command */ |
| 830 | rc = register_early_external_interrupt(0x2401, sclp_check_handler, |
| 831 | &ext_int_info_hwc); |
| 832 | if (rc) { |
| 833 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 834 | return rc; |
| 835 | } |
| 836 | for (retry = 0; retry <= SCLP_INIT_RETRY; retry++) { |
| 837 | __sclp_make_init_req(0, 0); |
| 838 | sccb = (struct init_sccb *) sclp_init_req.sccb; |
Heiko Carstens | ab14de6 | 2007-02-05 21:18:37 +0100 | [diff] [blame] | 839 | rc = sclp_service_call(sclp_init_req.command, sccb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 840 | if (rc == -EIO) |
| 841 | break; |
| 842 | sclp_init_req.status = SCLP_REQ_RUNNING; |
| 843 | sclp_running_state = sclp_running_state_running; |
| 844 | __sclp_set_request_timer(SCLP_RETRY_INTERVAL * HZ, |
| 845 | sclp_check_timeout, 0); |
| 846 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 847 | /* Enable service-signal interruption - needs to happen |
| 848 | * with IRQs enabled. */ |
| 849 | ctl_set_bit(0, 9); |
| 850 | /* Wait for signal from interrupt or timeout */ |
| 851 | sclp_sync_wait(); |
| 852 | /* Disable service-signal interruption - needs to happen |
| 853 | * with IRQs enabled. */ |
| 854 | ctl_clear_bit(0,9); |
| 855 | spin_lock_irqsave(&sclp_lock, flags); |
| 856 | del_timer(&sclp_request_timer); |
| 857 | if (sclp_init_req.status == SCLP_REQ_DONE && |
| 858 | sccb->header.response_code == 0x20) { |
| 859 | rc = 0; |
| 860 | break; |
| 861 | } else |
| 862 | rc = -EBUSY; |
| 863 | } |
| 864 | unregister_early_external_interrupt(0x2401, sclp_check_handler, |
| 865 | &ext_int_info_hwc); |
| 866 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 867 | return rc; |
| 868 | } |
| 869 | |
| 870 | /* Reboot event handler. Reset send and receive mask to prevent pending SCLP |
| 871 | * events from interfering with rebooted system. */ |
| 872 | static int |
| 873 | sclp_reboot_event(struct notifier_block *this, unsigned long event, void *ptr) |
| 874 | { |
| 875 | sclp_deactivate(); |
| 876 | return NOTIFY_DONE; |
| 877 | } |
| 878 | |
| 879 | static struct notifier_block sclp_reboot_notifier = { |
| 880 | .notifier_call = sclp_reboot_event |
| 881 | }; |
| 882 | |
| 883 | /* Initialize SCLP driver. Return zero if driver is operational, non-zero |
| 884 | * otherwise. */ |
| 885 | static int |
| 886 | sclp_init(void) |
| 887 | { |
| 888 | unsigned long flags; |
| 889 | int rc; |
| 890 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 891 | spin_lock_irqsave(&sclp_lock, flags); |
| 892 | /* Check for previous or running initialization */ |
| 893 | if (sclp_init_state != sclp_init_state_uninitialized) { |
| 894 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 895 | return 0; |
| 896 | } |
| 897 | sclp_init_state = sclp_init_state_initializing; |
| 898 | /* Set up variables */ |
| 899 | INIT_LIST_HEAD(&sclp_req_queue); |
| 900 | INIT_LIST_HEAD(&sclp_reg_list); |
| 901 | list_add(&sclp_state_change_event.list, &sclp_reg_list); |
| 902 | init_timer(&sclp_request_timer); |
| 903 | /* Check interface */ |
| 904 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 905 | rc = sclp_check_interface(); |
| 906 | spin_lock_irqsave(&sclp_lock, flags); |
| 907 | if (rc) { |
| 908 | sclp_init_state = sclp_init_state_uninitialized; |
| 909 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 910 | return rc; |
| 911 | } |
| 912 | /* Register reboot handler */ |
| 913 | rc = register_reboot_notifier(&sclp_reboot_notifier); |
| 914 | if (rc) { |
| 915 | sclp_init_state = sclp_init_state_uninitialized; |
| 916 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 917 | return rc; |
| 918 | } |
| 919 | /* Register interrupt handler */ |
| 920 | rc = register_early_external_interrupt(0x2401, sclp_interrupt_handler, |
| 921 | &ext_int_info_hwc); |
| 922 | if (rc) { |
| 923 | unregister_reboot_notifier(&sclp_reboot_notifier); |
| 924 | sclp_init_state = sclp_init_state_uninitialized; |
| 925 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 926 | return rc; |
| 927 | } |
| 928 | sclp_init_state = sclp_init_state_initialized; |
| 929 | spin_unlock_irqrestore(&sclp_lock, flags); |
| 930 | /* Enable service-signal external interruption - needs to happen with |
| 931 | * IRQs enabled. */ |
| 932 | ctl_set_bit(0, 9); |
| 933 | sclp_init_mask(1); |
| 934 | return 0; |
| 935 | } |
Peter Oberparleiter | b3d00c3 | 2007-04-27 16:01:51 +0200 | [diff] [blame] | 936 | |
| 937 | static __init int sclp_initcall(void) |
| 938 | { |
| 939 | return sclp_init(); |
| 940 | } |
| 941 | |
| 942 | arch_initcall(sclp_initcall); |