Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * SN Platform system controller communication support | |
3 | * | |
4 | * This file is subject to the terms and conditions of the GNU General Public | |
5 | * License. See the file "COPYING" in the main directory of this archive | |
6 | * for more details. | |
7 | * | |
40953ed8 | 8 | * Copyright (C) 2004, 2006 Silicon Graphics, Inc. All rights reserved. |
1da177e4 LT |
9 | */ |
10 | ||
11 | /* | |
12 | * System controller communication driver | |
13 | * | |
14 | * This driver allows a user process to communicate with the system | |
15 | * controller (a.k.a. "IRouter") network in an SGI SN system. | |
16 | */ | |
17 | ||
18 | #include <linux/interrupt.h> | |
19 | #include <linux/sched.h> | |
20 | #include <linux/device.h> | |
21 | #include <linux/poll.h> | |
22 | #include <linux/module.h> | |
23 | #include <linux/slab.h> | |
c43ef174 | 24 | #include <linux/smp_lock.h> |
1da177e4 LT |
25 | #include <asm/sn/io.h> |
26 | #include <asm/sn/sn_sal.h> | |
27 | #include <asm/sn/module.h> | |
28 | #include <asm/sn/geo.h> | |
29 | #include <asm/sn/nodepda.h> | |
30 | #include "snsc.h" | |
31 | ||
32 | #define SYSCTL_BASENAME "snsc" | |
33 | ||
34 | #define SCDRV_BUFSZ 2048 | |
35 | #define SCDRV_TIMEOUT 1000 | |
36 | ||
37 | static irqreturn_t | |
7d12e780 | 38 | scdrv_interrupt(int irq, void *subch_data) |
1da177e4 LT |
39 | { |
40 | struct subch_data_s *sd = subch_data; | |
41 | unsigned long flags; | |
42 | int status; | |
43 | ||
44 | spin_lock_irqsave(&sd->sd_rlock, flags); | |
45 | spin_lock(&sd->sd_wlock); | |
46 | status = ia64_sn_irtr_intr(sd->sd_nasid, sd->sd_subch); | |
47 | ||
48 | if (status > 0) { | |
49 | if (status & SAL_IROUTER_INTR_RECV) { | |
50 | wake_up(&sd->sd_rq); | |
51 | } | |
52 | if (status & SAL_IROUTER_INTR_XMIT) { | |
53 | ia64_sn_irtr_intr_disable | |
54 | (sd->sd_nasid, sd->sd_subch, | |
55 | SAL_IROUTER_INTR_XMIT); | |
56 | wake_up(&sd->sd_wq); | |
57 | } | |
58 | } | |
59 | spin_unlock(&sd->sd_wlock); | |
60 | spin_unlock_irqrestore(&sd->sd_rlock, flags); | |
61 | return IRQ_HANDLED; | |
62 | } | |
63 | ||
64 | /* | |
65 | * scdrv_open | |
66 | * | |
67 | * Reserve a subchannel for system controller communication. | |
68 | */ | |
69 | ||
70 | static int | |
71 | scdrv_open(struct inode *inode, struct file *file) | |
72 | { | |
73 | struct sysctl_data_s *scd; | |
74 | struct subch_data_s *sd; | |
75 | int rv; | |
76 | ||
77 | /* look up device info for this device file */ | |
78 | scd = container_of(inode->i_cdev, struct sysctl_data_s, scd_cdev); | |
79 | ||
80 | /* allocate memory for subchannel data */ | |
40953ed8 | 81 | sd = kzalloc(sizeof (struct subch_data_s), GFP_KERNEL); |
1da177e4 LT |
82 | if (sd == NULL) { |
83 | printk("%s: couldn't allocate subchannel data\n", | |
bf9d8929 | 84 | __func__); |
1da177e4 LT |
85 | return -ENOMEM; |
86 | } | |
87 | ||
88 | /* initialize subch_data_s fields */ | |
1da177e4 LT |
89 | sd->sd_nasid = scd->scd_nasid; |
90 | sd->sd_subch = ia64_sn_irtr_open(scd->scd_nasid); | |
91 | ||
92 | if (sd->sd_subch < 0) { | |
93 | kfree(sd); | |
bf9d8929 | 94 | printk("%s: couldn't allocate subchannel\n", __func__); |
1da177e4 LT |
95 | return -EBUSY; |
96 | } | |
97 | ||
98 | spin_lock_init(&sd->sd_rlock); | |
99 | spin_lock_init(&sd->sd_wlock); | |
100 | init_waitqueue_head(&sd->sd_rq); | |
101 | init_waitqueue_head(&sd->sd_wq); | |
102 | sema_init(&sd->sd_rbs, 1); | |
103 | sema_init(&sd->sd_wbs, 1); | |
104 | ||
105 | file->private_data = sd; | |
106 | ||
107 | /* hook this subchannel up to the system controller interrupt */ | |
c43ef174 | 108 | lock_kernel(); |
1da177e4 | 109 | rv = request_irq(SGI_UART_VECTOR, scdrv_interrupt, |
0f2ed4c6 | 110 | IRQF_SHARED | IRQF_DISABLED, |
1da177e4 LT |
111 | SYSCTL_BASENAME, sd); |
112 | if (rv) { | |
113 | ia64_sn_irtr_close(sd->sd_nasid, sd->sd_subch); | |
114 | kfree(sd); | |
bf9d8929 | 115 | printk("%s: irq request failed (%d)\n", __func__, rv); |
c43ef174 | 116 | unlock_kernel(); |
1da177e4 LT |
117 | return -EBUSY; |
118 | } | |
c43ef174 | 119 | unlock_kernel(); |
1da177e4 LT |
120 | return 0; |
121 | } | |
122 | ||
123 | /* | |
124 | * scdrv_release | |
125 | * | |
126 | * Release a previously-reserved subchannel. | |
127 | */ | |
128 | ||
129 | static int | |
130 | scdrv_release(struct inode *inode, struct file *file) | |
131 | { | |
132 | struct subch_data_s *sd = (struct subch_data_s *) file->private_data; | |
133 | int rv; | |
134 | ||
135 | /* free the interrupt */ | |
136 | free_irq(SGI_UART_VECTOR, sd); | |
137 | ||
138 | /* ask SAL to close the subchannel */ | |
139 | rv = ia64_sn_irtr_close(sd->sd_nasid, sd->sd_subch); | |
140 | ||
141 | kfree(sd); | |
142 | return rv; | |
143 | } | |
144 | ||
145 | /* | |
146 | * scdrv_read | |
147 | * | |
148 | * Called to read bytes from the open IRouter pipe. | |
149 | * | |
150 | */ | |
151 | ||
152 | static inline int | |
153 | read_status_check(struct subch_data_s *sd, int *len) | |
154 | { | |
155 | return ia64_sn_irtr_recv(sd->sd_nasid, sd->sd_subch, sd->sd_rb, len); | |
156 | } | |
157 | ||
158 | static ssize_t | |
159 | scdrv_read(struct file *file, char __user *buf, size_t count, loff_t *f_pos) | |
160 | { | |
161 | int status; | |
162 | int len; | |
163 | unsigned long flags; | |
164 | struct subch_data_s *sd = (struct subch_data_s *) file->private_data; | |
165 | ||
166 | /* try to get control of the read buffer */ | |
167 | if (down_trylock(&sd->sd_rbs)) { | |
168 | /* somebody else has it now; | |
169 | * if we're non-blocking, then exit... | |
170 | */ | |
171 | if (file->f_flags & O_NONBLOCK) { | |
172 | return -EAGAIN; | |
173 | } | |
174 | /* ...or if we want to block, then do so here */ | |
175 | if (down_interruptible(&sd->sd_rbs)) { | |
176 | /* something went wrong with wait */ | |
177 | return -ERESTARTSYS; | |
178 | } | |
179 | } | |
180 | ||
181 | /* anything to read? */ | |
182 | len = CHUNKSIZE; | |
183 | spin_lock_irqsave(&sd->sd_rlock, flags); | |
184 | status = read_status_check(sd, &len); | |
185 | ||
186 | /* if not, and we're blocking I/O, loop */ | |
187 | while (status < 0) { | |
188 | DECLARE_WAITQUEUE(wait, current); | |
189 | ||
190 | if (file->f_flags & O_NONBLOCK) { | |
191 | spin_unlock_irqrestore(&sd->sd_rlock, flags); | |
192 | up(&sd->sd_rbs); | |
193 | return -EAGAIN; | |
194 | } | |
195 | ||
196 | len = CHUNKSIZE; | |
197 | set_current_state(TASK_INTERRUPTIBLE); | |
198 | add_wait_queue(&sd->sd_rq, &wait); | |
199 | spin_unlock_irqrestore(&sd->sd_rlock, flags); | |
200 | ||
201 | schedule_timeout(SCDRV_TIMEOUT); | |
202 | ||
203 | remove_wait_queue(&sd->sd_rq, &wait); | |
204 | if (signal_pending(current)) { | |
205 | /* wait was interrupted */ | |
206 | up(&sd->sd_rbs); | |
207 | return -ERESTARTSYS; | |
208 | } | |
209 | ||
210 | spin_lock_irqsave(&sd->sd_rlock, flags); | |
211 | status = read_status_check(sd, &len); | |
212 | } | |
213 | spin_unlock_irqrestore(&sd->sd_rlock, flags); | |
214 | ||
215 | if (len > 0) { | |
216 | /* we read something in the last read_status_check(); copy | |
217 | * it out to user space | |
218 | */ | |
219 | if (count < len) { | |
220 | pr_debug("%s: only accepting %d of %d bytes\n", | |
bf9d8929 | 221 | __func__, (int) count, len); |
1da177e4 LT |
222 | } |
223 | len = min((int) count, len); | |
224 | if (copy_to_user(buf, sd->sd_rb, len)) | |
225 | len = -EFAULT; | |
226 | } | |
227 | ||
228 | /* release the read buffer and wake anyone who might be | |
229 | * waiting for it | |
230 | */ | |
231 | up(&sd->sd_rbs); | |
232 | ||
233 | /* return the number of characters read in */ | |
234 | return len; | |
235 | } | |
236 | ||
237 | /* | |
238 | * scdrv_write | |
239 | * | |
240 | * Writes a chunk of an IRouter packet (or other system controller data) | |
241 | * to the system controller. | |
242 | * | |
243 | */ | |
244 | static inline int | |
245 | write_status_check(struct subch_data_s *sd, int count) | |
246 | { | |
247 | return ia64_sn_irtr_send(sd->sd_nasid, sd->sd_subch, sd->sd_wb, count); | |
248 | } | |
249 | ||
250 | static ssize_t | |
251 | scdrv_write(struct file *file, const char __user *buf, | |
252 | size_t count, loff_t *f_pos) | |
253 | { | |
254 | unsigned long flags; | |
255 | int status; | |
256 | struct subch_data_s *sd = (struct subch_data_s *) file->private_data; | |
257 | ||
258 | /* try to get control of the write buffer */ | |
259 | if (down_trylock(&sd->sd_wbs)) { | |
260 | /* somebody else has it now; | |
261 | * if we're non-blocking, then exit... | |
262 | */ | |
263 | if (file->f_flags & O_NONBLOCK) { | |
264 | return -EAGAIN; | |
265 | } | |
266 | /* ...or if we want to block, then do so here */ | |
267 | if (down_interruptible(&sd->sd_wbs)) { | |
268 | /* something went wrong with wait */ | |
269 | return -ERESTARTSYS; | |
270 | } | |
271 | } | |
272 | ||
273 | count = min((int) count, CHUNKSIZE); | |
274 | if (copy_from_user(sd->sd_wb, buf, count)) { | |
275 | up(&sd->sd_wbs); | |
276 | return -EFAULT; | |
277 | } | |
278 | ||
279 | /* try to send the buffer */ | |
280 | spin_lock_irqsave(&sd->sd_wlock, flags); | |
281 | status = write_status_check(sd, count); | |
282 | ||
283 | /* if we failed, and we want to block, then loop */ | |
284 | while (status <= 0) { | |
285 | DECLARE_WAITQUEUE(wait, current); | |
286 | ||
287 | if (file->f_flags & O_NONBLOCK) { | |
288 | spin_unlock(&sd->sd_wlock); | |
289 | up(&sd->sd_wbs); | |
290 | return -EAGAIN; | |
291 | } | |
292 | ||
293 | set_current_state(TASK_INTERRUPTIBLE); | |
294 | add_wait_queue(&sd->sd_wq, &wait); | |
295 | spin_unlock_irqrestore(&sd->sd_wlock, flags); | |
296 | ||
297 | schedule_timeout(SCDRV_TIMEOUT); | |
298 | ||
299 | remove_wait_queue(&sd->sd_wq, &wait); | |
300 | if (signal_pending(current)) { | |
301 | /* wait was interrupted */ | |
302 | up(&sd->sd_wbs); | |
303 | return -ERESTARTSYS; | |
304 | } | |
305 | ||
306 | spin_lock_irqsave(&sd->sd_wlock, flags); | |
307 | status = write_status_check(sd, count); | |
308 | } | |
309 | spin_unlock_irqrestore(&sd->sd_wlock, flags); | |
310 | ||
311 | /* release the write buffer and wake anyone who's waiting for it */ | |
312 | up(&sd->sd_wbs); | |
313 | ||
314 | /* return the number of characters accepted (should be the complete | |
315 | * "chunk" as requested) | |
316 | */ | |
317 | if ((status >= 0) && (status < count)) { | |
318 | pr_debug("Didn't accept the full chunk; %d of %d\n", | |
319 | status, (int) count); | |
320 | } | |
321 | return status; | |
322 | } | |
323 | ||
324 | static unsigned int | |
325 | scdrv_poll(struct file *file, struct poll_table_struct *wait) | |
326 | { | |
327 | unsigned int mask = 0; | |
328 | int status = 0; | |
329 | struct subch_data_s *sd = (struct subch_data_s *) file->private_data; | |
330 | unsigned long flags; | |
331 | ||
332 | poll_wait(file, &sd->sd_rq, wait); | |
333 | poll_wait(file, &sd->sd_wq, wait); | |
334 | ||
335 | spin_lock_irqsave(&sd->sd_rlock, flags); | |
336 | spin_lock(&sd->sd_wlock); | |
337 | status = ia64_sn_irtr_intr(sd->sd_nasid, sd->sd_subch); | |
338 | spin_unlock(&sd->sd_wlock); | |
339 | spin_unlock_irqrestore(&sd->sd_rlock, flags); | |
340 | ||
341 | if (status > 0) { | |
342 | if (status & SAL_IROUTER_INTR_RECV) { | |
343 | mask |= POLLIN | POLLRDNORM; | |
344 | } | |
345 | if (status & SAL_IROUTER_INTR_XMIT) { | |
346 | mask |= POLLOUT | POLLWRNORM; | |
347 | } | |
348 | } | |
349 | ||
350 | return mask; | |
351 | } | |
352 | ||
62322d25 | 353 | static const struct file_operations scdrv_fops = { |
1da177e4 LT |
354 | .owner = THIS_MODULE, |
355 | .read = scdrv_read, | |
356 | .write = scdrv_write, | |
357 | .poll = scdrv_poll, | |
358 | .open = scdrv_open, | |
359 | .release = scdrv_release, | |
360 | }; | |
361 | ||
ca8eca68 | 362 | static struct class *snsc_class; |
363 | ||
1da177e4 LT |
364 | /* |
365 | * scdrv_init | |
366 | * | |
367 | * Called at boot time to initialize the system controller communication | |
368 | * facility. | |
369 | */ | |
370 | int __init | |
371 | scdrv_init(void) | |
372 | { | |
373 | geoid_t geoid; | |
374 | cnodeid_t cnode; | |
375 | char devname[32]; | |
376 | char *devnamep; | |
377 | struct sysctl_data_s *scd; | |
378 | void *salbuf; | |
1da177e4 | 379 | dev_t first_dev, dev; |
c7c17423 GE |
380 | nasid_t event_nasid; |
381 | ||
382 | if (!ia64_platform_is("sn2")) | |
383 | return -ENODEV; | |
384 | ||
385 | event_nasid = ia64_sn_get_console_nasid(); | |
1da177e4 | 386 | |
24ee0a6d | 387 | if (alloc_chrdev_region(&first_dev, 0, num_cnodes, |
1da177e4 LT |
388 | SYSCTL_BASENAME) < 0) { |
389 | printk("%s: failed to register SN system controller device\n", | |
bf9d8929 | 390 | __func__); |
1da177e4 LT |
391 | return -ENODEV; |
392 | } | |
ca8eca68 | 393 | snsc_class = class_create(THIS_MODULE, SYSCTL_BASENAME); |
1da177e4 | 394 | |
24ee0a6d | 395 | for (cnode = 0; cnode < num_cnodes; cnode++) { |
1da177e4 LT |
396 | geoid = cnodeid_get_geoid(cnode); |
397 | devnamep = devname; | |
398 | format_module_id(devnamep, geo_module(geoid), | |
399 | MODULE_FORMAT_BRIEF); | |
400 | devnamep = devname + strlen(devname); | |
8c4335a8 | 401 | sprintf(devnamep, "^%d#%d", geo_slot(geoid), |
402 | geo_slab(geoid)); | |
1da177e4 LT |
403 | |
404 | /* allocate sysctl device data */ | |
40953ed8 | 405 | scd = kzalloc(sizeof (struct sysctl_data_s), |
1da177e4 LT |
406 | GFP_KERNEL); |
407 | if (!scd) { | |
408 | printk("%s: failed to allocate device info" | |
bf9d8929 | 409 | "for %s/%s\n", __func__, |
1da177e4 LT |
410 | SYSCTL_BASENAME, devname); |
411 | continue; | |
412 | } | |
1da177e4 LT |
413 | |
414 | /* initialize sysctl device data fields */ | |
415 | scd->scd_nasid = cnodeid_to_nasid(cnode); | |
416 | if (!(salbuf = kmalloc(SCDRV_BUFSZ, GFP_KERNEL))) { | |
417 | printk("%s: failed to allocate driver buffer" | |
bf9d8929 | 418 | "(%s%s)\n", __func__, |
1da177e4 LT |
419 | SYSCTL_BASENAME, devname); |
420 | kfree(scd); | |
421 | continue; | |
422 | } | |
423 | ||
424 | if (ia64_sn_irtr_init(scd->scd_nasid, salbuf, | |
425 | SCDRV_BUFSZ) < 0) { | |
426 | printk | |
427 | ("%s: failed to initialize SAL for" | |
428 | " system controller communication" | |
429 | " (%s/%s): outdated PROM?\n", | |
bf9d8929 | 430 | __func__, SYSCTL_BASENAME, devname); |
1da177e4 LT |
431 | kfree(scd); |
432 | kfree(salbuf); | |
433 | continue; | |
434 | } | |
435 | ||
436 | dev = first_dev + cnode; | |
437 | cdev_init(&scd->scd_cdev, &scdrv_fops); | |
438 | if (cdev_add(&scd->scd_cdev, dev, 1)) { | |
439 | printk("%s: failed to register system" | |
440 | " controller device (%s%s)\n", | |
bf9d8929 | 441 | __func__, SYSCTL_BASENAME, devname); |
1da177e4 LT |
442 | kfree(scd); |
443 | kfree(salbuf); | |
444 | continue; | |
445 | } | |
446 | ||
07c015e7 | 447 | device_create(snsc_class, NULL, dev, "%s", devname); |
1da177e4 LT |
448 | |
449 | ia64_sn_irtr_intr_enable(scd->scd_nasid, | |
450 | 0 /*ignored */ , | |
451 | SAL_IROUTER_INTR_RECV); | |
67639deb GH |
452 | |
453 | /* on the console nasid, prepare to receive | |
454 | * system controller environmental events | |
455 | */ | |
456 | if(scd->scd_nasid == event_nasid) { | |
457 | scdrv_event_init(scd); | |
458 | } | |
1da177e4 LT |
459 | } |
460 | return 0; | |
461 | } | |
462 | ||
463 | module_init(scdrv_init); |