xref: /openbmc/linux/drivers/misc/hpilo.c (revision 6d99a79c)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for the HP iLO management processor.
4  *
5  * Copyright (C) 2008 Hewlett-Packard Development Company, L.P.
6  *	David Altobelli <david.altobelli@hpe.com>
7  */
8 #include <linux/kernel.h>
9 #include <linux/types.h>
10 #include <linux/module.h>
11 #include <linux/fs.h>
12 #include <linux/pci.h>
13 #include <linux/interrupt.h>
14 #include <linux/ioport.h>
15 #include <linux/device.h>
16 #include <linux/file.h>
17 #include <linux/cdev.h>
18 #include <linux/sched.h>
19 #include <linux/spinlock.h>
20 #include <linux/delay.h>
21 #include <linux/uaccess.h>
22 #include <linux/io.h>
23 #include <linux/wait.h>
24 #include <linux/poll.h>
25 #include <linux/slab.h>
26 #include "hpilo.h"
27 
28 static struct class *ilo_class;
29 static unsigned int ilo_major;
30 static unsigned int max_ccb = 16;
31 static char ilo_hwdev[MAX_ILO_DEV];
32 
33 static inline int get_entry_id(int entry)
34 {
35 	return (entry & ENTRY_MASK_DESCRIPTOR) >> ENTRY_BITPOS_DESCRIPTOR;
36 }
37 
38 static inline int get_entry_len(int entry)
39 {
40 	return ((entry & ENTRY_MASK_QWORDS) >> ENTRY_BITPOS_QWORDS) << 3;
41 }
42 
43 static inline int mk_entry(int id, int len)
44 {
45 	int qlen = len & 7 ? (len >> 3) + 1 : len >> 3;
46 	return id << ENTRY_BITPOS_DESCRIPTOR | qlen << ENTRY_BITPOS_QWORDS;
47 }
48 
49 static inline int desc_mem_sz(int nr_entry)
50 {
51 	return nr_entry << L2_QENTRY_SZ;
52 }
53 
54 /*
55  * FIFO queues, shared with hardware.
56  *
57  * If a queue has empty slots, an entry is added to the queue tail,
58  * and that entry is marked as occupied.
59  * Entries can be dequeued from the head of the list, when the device
60  * has marked the entry as consumed.
61  *
62  * Returns true on successful queue/dequeue, false on failure.
63  */
64 static int fifo_enqueue(struct ilo_hwinfo *hw, char *fifobar, int entry)
65 {
66 	struct fifo *fifo_q = FIFOBARTOHANDLE(fifobar);
67 	unsigned long flags;
68 	int ret = 0;
69 
70 	spin_lock_irqsave(&hw->fifo_lock, flags);
71 	if (!(fifo_q->fifobar[(fifo_q->tail + 1) & fifo_q->imask]
72 	      & ENTRY_MASK_O)) {
73 		fifo_q->fifobar[fifo_q->tail & fifo_q->imask] |=
74 				(entry & ENTRY_MASK_NOSTATE) | fifo_q->merge;
75 		fifo_q->tail += 1;
76 		ret = 1;
77 	}
78 	spin_unlock_irqrestore(&hw->fifo_lock, flags);
79 
80 	return ret;
81 }
82 
83 static int fifo_dequeue(struct ilo_hwinfo *hw, char *fifobar, int *entry)
84 {
85 	struct fifo *fifo_q = FIFOBARTOHANDLE(fifobar);
86 	unsigned long flags;
87 	int ret = 0;
88 	u64 c;
89 
90 	spin_lock_irqsave(&hw->fifo_lock, flags);
91 	c = fifo_q->fifobar[fifo_q->head & fifo_q->imask];
92 	if (c & ENTRY_MASK_C) {
93 		if (entry)
94 			*entry = c & ENTRY_MASK_NOSTATE;
95 
96 		fifo_q->fifobar[fifo_q->head & fifo_q->imask] =
97 							(c | ENTRY_MASK) + 1;
98 		fifo_q->head += 1;
99 		ret = 1;
100 	}
101 	spin_unlock_irqrestore(&hw->fifo_lock, flags);
102 
103 	return ret;
104 }
105 
106 static int fifo_check_recv(struct ilo_hwinfo *hw, char *fifobar)
107 {
108 	struct fifo *fifo_q = FIFOBARTOHANDLE(fifobar);
109 	unsigned long flags;
110 	int ret = 0;
111 	u64 c;
112 
113 	spin_lock_irqsave(&hw->fifo_lock, flags);
114 	c = fifo_q->fifobar[fifo_q->head & fifo_q->imask];
115 	if (c & ENTRY_MASK_C)
116 		ret = 1;
117 	spin_unlock_irqrestore(&hw->fifo_lock, flags);
118 
119 	return ret;
120 }
121 
122 static int ilo_pkt_enqueue(struct ilo_hwinfo *hw, struct ccb *ccb,
123 			   int dir, int id, int len)
124 {
125 	char *fifobar;
126 	int entry;
127 
128 	if (dir == SENDQ)
129 		fifobar = ccb->ccb_u1.send_fifobar;
130 	else
131 		fifobar = ccb->ccb_u3.recv_fifobar;
132 
133 	entry = mk_entry(id, len);
134 	return fifo_enqueue(hw, fifobar, entry);
135 }
136 
137 static int ilo_pkt_dequeue(struct ilo_hwinfo *hw, struct ccb *ccb,
138 			   int dir, int *id, int *len, void **pkt)
139 {
140 	char *fifobar, *desc;
141 	int entry = 0, pkt_id = 0;
142 	int ret;
143 
144 	if (dir == SENDQ) {
145 		fifobar = ccb->ccb_u1.send_fifobar;
146 		desc = ccb->ccb_u2.send_desc;
147 	} else {
148 		fifobar = ccb->ccb_u3.recv_fifobar;
149 		desc = ccb->ccb_u4.recv_desc;
150 	}
151 
152 	ret = fifo_dequeue(hw, fifobar, &entry);
153 	if (ret) {
154 		pkt_id = get_entry_id(entry);
155 		if (id)
156 			*id = pkt_id;
157 		if (len)
158 			*len = get_entry_len(entry);
159 		if (pkt)
160 			*pkt = (void *)(desc + desc_mem_sz(pkt_id));
161 	}
162 
163 	return ret;
164 }
165 
166 static int ilo_pkt_recv(struct ilo_hwinfo *hw, struct ccb *ccb)
167 {
168 	char *fifobar = ccb->ccb_u3.recv_fifobar;
169 
170 	return fifo_check_recv(hw, fifobar);
171 }
172 
173 static inline void doorbell_set(struct ccb *ccb)
174 {
175 	iowrite8(1, ccb->ccb_u5.db_base);
176 }
177 
178 static inline void doorbell_clr(struct ccb *ccb)
179 {
180 	iowrite8(2, ccb->ccb_u5.db_base);
181 }
182 
183 static inline int ctrl_set(int l2sz, int idxmask, int desclim)
184 {
185 	int active = 0, go = 1;
186 	return l2sz << CTRL_BITPOS_L2SZ |
187 	       idxmask << CTRL_BITPOS_FIFOINDEXMASK |
188 	       desclim << CTRL_BITPOS_DESCLIMIT |
189 	       active << CTRL_BITPOS_A |
190 	       go << CTRL_BITPOS_G;
191 }
192 
193 static void ctrl_setup(struct ccb *ccb, int nr_desc, int l2desc_sz)
194 {
195 	/* for simplicity, use the same parameters for send and recv ctrls */
196 	ccb->send_ctrl = ctrl_set(l2desc_sz, nr_desc-1, nr_desc-1);
197 	ccb->recv_ctrl = ctrl_set(l2desc_sz, nr_desc-1, nr_desc-1);
198 }
199 
200 static inline int fifo_sz(int nr_entry)
201 {
202 	/* size of a fifo is determined by the number of entries it contains */
203 	return (nr_entry * sizeof(u64)) + FIFOHANDLESIZE;
204 }
205 
206 static void fifo_setup(void *base_addr, int nr_entry)
207 {
208 	struct fifo *fifo_q = base_addr;
209 	int i;
210 
211 	/* set up an empty fifo */
212 	fifo_q->head = 0;
213 	fifo_q->tail = 0;
214 	fifo_q->reset = 0;
215 	fifo_q->nrents = nr_entry;
216 	fifo_q->imask = nr_entry - 1;
217 	fifo_q->merge = ENTRY_MASK_O;
218 
219 	for (i = 0; i < nr_entry; i++)
220 		fifo_q->fifobar[i] = 0;
221 }
222 
223 static void ilo_ccb_close(struct pci_dev *pdev, struct ccb_data *data)
224 {
225 	struct ccb *driver_ccb = &data->driver_ccb;
226 	struct ccb __iomem *device_ccb = data->mapped_ccb;
227 	int retries;
228 
229 	/* complicated dance to tell the hw we are stopping */
230 	doorbell_clr(driver_ccb);
231 	iowrite32(ioread32(&device_ccb->send_ctrl) & ~(1 << CTRL_BITPOS_G),
232 		  &device_ccb->send_ctrl);
233 	iowrite32(ioread32(&device_ccb->recv_ctrl) & ~(1 << CTRL_BITPOS_G),
234 		  &device_ccb->recv_ctrl);
235 
236 	/* give iLO some time to process stop request */
237 	for (retries = MAX_WAIT; retries > 0; retries--) {
238 		doorbell_set(driver_ccb);
239 		udelay(WAIT_TIME);
240 		if (!(ioread32(&device_ccb->send_ctrl) & (1 << CTRL_BITPOS_A))
241 		    &&
242 		    !(ioread32(&device_ccb->recv_ctrl) & (1 << CTRL_BITPOS_A)))
243 			break;
244 	}
245 	if (retries == 0)
246 		dev_err(&pdev->dev, "Closing, but controller still active\n");
247 
248 	/* clear the hw ccb */
249 	memset_io(device_ccb, 0, sizeof(struct ccb));
250 
251 	/* free resources used to back send/recv queues */
252 	pci_free_consistent(pdev, data->dma_size, data->dma_va, data->dma_pa);
253 }
254 
255 static int ilo_ccb_setup(struct ilo_hwinfo *hw, struct ccb_data *data, int slot)
256 {
257 	char *dma_va;
258 	dma_addr_t dma_pa;
259 	struct ccb *driver_ccb, *ilo_ccb;
260 
261 	driver_ccb = &data->driver_ccb;
262 	ilo_ccb = &data->ilo_ccb;
263 
264 	data->dma_size = 2 * fifo_sz(NR_QENTRY) +
265 			 2 * desc_mem_sz(NR_QENTRY) +
266 			 ILO_START_ALIGN + ILO_CACHE_SZ;
267 
268 	data->dma_va = pci_alloc_consistent(hw->ilo_dev, data->dma_size,
269 					    &data->dma_pa);
270 	if (!data->dma_va)
271 		return -ENOMEM;
272 
273 	dma_va = (char *)data->dma_va;
274 	dma_pa = data->dma_pa;
275 
276 	memset(dma_va, 0, data->dma_size);
277 
278 	dma_va = (char *)roundup((unsigned long)dma_va, ILO_START_ALIGN);
279 	dma_pa = roundup(dma_pa, ILO_START_ALIGN);
280 
281 	/*
282 	 * Create two ccb's, one with virt addrs, one with phys addrs.
283 	 * Copy the phys addr ccb to device shared mem.
284 	 */
285 	ctrl_setup(driver_ccb, NR_QENTRY, L2_QENTRY_SZ);
286 	ctrl_setup(ilo_ccb, NR_QENTRY, L2_QENTRY_SZ);
287 
288 	fifo_setup(dma_va, NR_QENTRY);
289 	driver_ccb->ccb_u1.send_fifobar = dma_va + FIFOHANDLESIZE;
290 	ilo_ccb->ccb_u1.send_fifobar_pa = dma_pa + FIFOHANDLESIZE;
291 	dma_va += fifo_sz(NR_QENTRY);
292 	dma_pa += fifo_sz(NR_QENTRY);
293 
294 	dma_va = (char *)roundup((unsigned long)dma_va, ILO_CACHE_SZ);
295 	dma_pa = roundup(dma_pa, ILO_CACHE_SZ);
296 
297 	fifo_setup(dma_va, NR_QENTRY);
298 	driver_ccb->ccb_u3.recv_fifobar = dma_va + FIFOHANDLESIZE;
299 	ilo_ccb->ccb_u3.recv_fifobar_pa = dma_pa + FIFOHANDLESIZE;
300 	dma_va += fifo_sz(NR_QENTRY);
301 	dma_pa += fifo_sz(NR_QENTRY);
302 
303 	driver_ccb->ccb_u2.send_desc = dma_va;
304 	ilo_ccb->ccb_u2.send_desc_pa = dma_pa;
305 	dma_pa += desc_mem_sz(NR_QENTRY);
306 	dma_va += desc_mem_sz(NR_QENTRY);
307 
308 	driver_ccb->ccb_u4.recv_desc = dma_va;
309 	ilo_ccb->ccb_u4.recv_desc_pa = dma_pa;
310 
311 	driver_ccb->channel = slot;
312 	ilo_ccb->channel = slot;
313 
314 	driver_ccb->ccb_u5.db_base = hw->db_vaddr + (slot << L2_DB_SIZE);
315 	ilo_ccb->ccb_u5.db_base = NULL; /* hw ccb's doorbell is not used */
316 
317 	return 0;
318 }
319 
320 static void ilo_ccb_open(struct ilo_hwinfo *hw, struct ccb_data *data, int slot)
321 {
322 	int pkt_id, pkt_sz;
323 	struct ccb *driver_ccb = &data->driver_ccb;
324 
325 	/* copy the ccb with physical addrs to device memory */
326 	data->mapped_ccb = (struct ccb __iomem *)
327 				(hw->ram_vaddr + (slot * ILOHW_CCB_SZ));
328 	memcpy_toio(data->mapped_ccb, &data->ilo_ccb, sizeof(struct ccb));
329 
330 	/* put packets on the send and receive queues */
331 	pkt_sz = 0;
332 	for (pkt_id = 0; pkt_id < NR_QENTRY; pkt_id++) {
333 		ilo_pkt_enqueue(hw, driver_ccb, SENDQ, pkt_id, pkt_sz);
334 		doorbell_set(driver_ccb);
335 	}
336 
337 	pkt_sz = desc_mem_sz(1);
338 	for (pkt_id = 0; pkt_id < NR_QENTRY; pkt_id++)
339 		ilo_pkt_enqueue(hw, driver_ccb, RECVQ, pkt_id, pkt_sz);
340 
341 	/* the ccb is ready to use */
342 	doorbell_clr(driver_ccb);
343 }
344 
345 static int ilo_ccb_verify(struct ilo_hwinfo *hw, struct ccb_data *data)
346 {
347 	int pkt_id, i;
348 	struct ccb *driver_ccb = &data->driver_ccb;
349 
350 	/* make sure iLO is really handling requests */
351 	for (i = MAX_WAIT; i > 0; i--) {
352 		if (ilo_pkt_dequeue(hw, driver_ccb, SENDQ, &pkt_id, NULL, NULL))
353 			break;
354 		udelay(WAIT_TIME);
355 	}
356 
357 	if (i == 0) {
358 		dev_err(&hw->ilo_dev->dev, "Open could not dequeue a packet\n");
359 		return -EBUSY;
360 	}
361 
362 	ilo_pkt_enqueue(hw, driver_ccb, SENDQ, pkt_id, 0);
363 	doorbell_set(driver_ccb);
364 	return 0;
365 }
366 
367 static inline int is_channel_reset(struct ccb *ccb)
368 {
369 	/* check for this particular channel needing a reset */
370 	return FIFOBARTOHANDLE(ccb->ccb_u1.send_fifobar)->reset;
371 }
372 
373 static inline void set_channel_reset(struct ccb *ccb)
374 {
375 	/* set a flag indicating this channel needs a reset */
376 	FIFOBARTOHANDLE(ccb->ccb_u1.send_fifobar)->reset = 1;
377 }
378 
379 static inline int get_device_outbound(struct ilo_hwinfo *hw)
380 {
381 	return ioread32(&hw->mmio_vaddr[DB_OUT]);
382 }
383 
384 static inline int is_db_reset(int db_out)
385 {
386 	return db_out & (1 << DB_RESET);
387 }
388 
389 static inline int is_device_reset(struct ilo_hwinfo *hw)
390 {
391 	/* check for global reset condition */
392 	return is_db_reset(get_device_outbound(hw));
393 }
394 
395 static inline void clear_pending_db(struct ilo_hwinfo *hw, int clr)
396 {
397 	iowrite32(clr, &hw->mmio_vaddr[DB_OUT]);
398 }
399 
400 static inline void clear_device(struct ilo_hwinfo *hw)
401 {
402 	/* clear the device (reset bits, pending channel entries) */
403 	clear_pending_db(hw, -1);
404 }
405 
406 static inline void ilo_enable_interrupts(struct ilo_hwinfo *hw)
407 {
408 	iowrite8(ioread8(&hw->mmio_vaddr[DB_IRQ]) | 1, &hw->mmio_vaddr[DB_IRQ]);
409 }
410 
411 static inline void ilo_disable_interrupts(struct ilo_hwinfo *hw)
412 {
413 	iowrite8(ioread8(&hw->mmio_vaddr[DB_IRQ]) & ~1,
414 		 &hw->mmio_vaddr[DB_IRQ]);
415 }
416 
417 static void ilo_set_reset(struct ilo_hwinfo *hw)
418 {
419 	int slot;
420 
421 	/*
422 	 * Mapped memory is zeroed on ilo reset, so set a per ccb flag
423 	 * to indicate that this ccb needs to be closed and reopened.
424 	 */
425 	for (slot = 0; slot < max_ccb; slot++) {
426 		if (!hw->ccb_alloc[slot])
427 			continue;
428 		set_channel_reset(&hw->ccb_alloc[slot]->driver_ccb);
429 	}
430 }
431 
432 static ssize_t ilo_read(struct file *fp, char __user *buf,
433 			size_t len, loff_t *off)
434 {
435 	int err, found, cnt, pkt_id, pkt_len;
436 	struct ccb_data *data = fp->private_data;
437 	struct ccb *driver_ccb = &data->driver_ccb;
438 	struct ilo_hwinfo *hw = data->ilo_hw;
439 	void *pkt;
440 
441 	if (is_channel_reset(driver_ccb)) {
442 		/*
443 		 * If the device has been reset, applications
444 		 * need to close and reopen all ccbs.
445 		 */
446 		return -ENODEV;
447 	}
448 
449 	/*
450 	 * This function is to be called when data is expected
451 	 * in the channel, and will return an error if no packet is found
452 	 * during the loop below.  The sleep/retry logic is to allow
453 	 * applications to call read() immediately post write(),
454 	 * and give iLO some time to process the sent packet.
455 	 */
456 	cnt = 20;
457 	do {
458 		/* look for a received packet */
459 		found = ilo_pkt_dequeue(hw, driver_ccb, RECVQ, &pkt_id,
460 					&pkt_len, &pkt);
461 		if (found)
462 			break;
463 		cnt--;
464 		msleep(100);
465 	} while (!found && cnt);
466 
467 	if (!found)
468 		return -EAGAIN;
469 
470 	/* only copy the length of the received packet */
471 	if (pkt_len < len)
472 		len = pkt_len;
473 
474 	err = copy_to_user(buf, pkt, len);
475 
476 	/* return the received packet to the queue */
477 	ilo_pkt_enqueue(hw, driver_ccb, RECVQ, pkt_id, desc_mem_sz(1));
478 
479 	return err ? -EFAULT : len;
480 }
481 
482 static ssize_t ilo_write(struct file *fp, const char __user *buf,
483 			 size_t len, loff_t *off)
484 {
485 	int err, pkt_id, pkt_len;
486 	struct ccb_data *data = fp->private_data;
487 	struct ccb *driver_ccb = &data->driver_ccb;
488 	struct ilo_hwinfo *hw = data->ilo_hw;
489 	void *pkt;
490 
491 	if (is_channel_reset(driver_ccb))
492 		return -ENODEV;
493 
494 	/* get a packet to send the user command */
495 	if (!ilo_pkt_dequeue(hw, driver_ccb, SENDQ, &pkt_id, &pkt_len, &pkt))
496 		return -EBUSY;
497 
498 	/* limit the length to the length of the packet */
499 	if (pkt_len < len)
500 		len = pkt_len;
501 
502 	/* on failure, set the len to 0 to return empty packet to the device */
503 	err = copy_from_user(pkt, buf, len);
504 	if (err)
505 		len = 0;
506 
507 	/* send the packet */
508 	ilo_pkt_enqueue(hw, driver_ccb, SENDQ, pkt_id, len);
509 	doorbell_set(driver_ccb);
510 
511 	return err ? -EFAULT : len;
512 }
513 
514 static __poll_t ilo_poll(struct file *fp, poll_table *wait)
515 {
516 	struct ccb_data *data = fp->private_data;
517 	struct ccb *driver_ccb = &data->driver_ccb;
518 
519 	poll_wait(fp, &data->ccb_waitq, wait);
520 
521 	if (is_channel_reset(driver_ccb))
522 		return EPOLLERR;
523 	else if (ilo_pkt_recv(data->ilo_hw, driver_ccb))
524 		return EPOLLIN | EPOLLRDNORM;
525 
526 	return 0;
527 }
528 
529 static int ilo_close(struct inode *ip, struct file *fp)
530 {
531 	int slot;
532 	struct ccb_data *data;
533 	struct ilo_hwinfo *hw;
534 	unsigned long flags;
535 
536 	slot = iminor(ip) % max_ccb;
537 	hw = container_of(ip->i_cdev, struct ilo_hwinfo, cdev);
538 
539 	spin_lock(&hw->open_lock);
540 
541 	if (hw->ccb_alloc[slot]->ccb_cnt == 1) {
542 
543 		data = fp->private_data;
544 
545 		spin_lock_irqsave(&hw->alloc_lock, flags);
546 		hw->ccb_alloc[slot] = NULL;
547 		spin_unlock_irqrestore(&hw->alloc_lock, flags);
548 
549 		ilo_ccb_close(hw->ilo_dev, data);
550 
551 		kfree(data);
552 	} else
553 		hw->ccb_alloc[slot]->ccb_cnt--;
554 
555 	spin_unlock(&hw->open_lock);
556 
557 	return 0;
558 }
559 
560 static int ilo_open(struct inode *ip, struct file *fp)
561 {
562 	int slot, error;
563 	struct ccb_data *data;
564 	struct ilo_hwinfo *hw;
565 	unsigned long flags;
566 
567 	slot = iminor(ip) % max_ccb;
568 	hw = container_of(ip->i_cdev, struct ilo_hwinfo, cdev);
569 
570 	/* new ccb allocation */
571 	data = kzalloc(sizeof(*data), GFP_KERNEL);
572 	if (!data)
573 		return -ENOMEM;
574 
575 	spin_lock(&hw->open_lock);
576 
577 	/* each fd private_data holds sw/hw view of ccb */
578 	if (hw->ccb_alloc[slot] == NULL) {
579 		/* create a channel control block for this minor */
580 		error = ilo_ccb_setup(hw, data, slot);
581 		if (error) {
582 			kfree(data);
583 			goto out;
584 		}
585 
586 		data->ccb_cnt = 1;
587 		data->ccb_excl = fp->f_flags & O_EXCL;
588 		data->ilo_hw = hw;
589 		init_waitqueue_head(&data->ccb_waitq);
590 
591 		/* write the ccb to hw */
592 		spin_lock_irqsave(&hw->alloc_lock, flags);
593 		ilo_ccb_open(hw, data, slot);
594 		hw->ccb_alloc[slot] = data;
595 		spin_unlock_irqrestore(&hw->alloc_lock, flags);
596 
597 		/* make sure the channel is functional */
598 		error = ilo_ccb_verify(hw, data);
599 		if (error) {
600 
601 			spin_lock_irqsave(&hw->alloc_lock, flags);
602 			hw->ccb_alloc[slot] = NULL;
603 			spin_unlock_irqrestore(&hw->alloc_lock, flags);
604 
605 			ilo_ccb_close(hw->ilo_dev, data);
606 
607 			kfree(data);
608 			goto out;
609 		}
610 
611 	} else {
612 		kfree(data);
613 		if (fp->f_flags & O_EXCL || hw->ccb_alloc[slot]->ccb_excl) {
614 			/*
615 			 * The channel exists, and either this open
616 			 * or a previous open of this channel wants
617 			 * exclusive access.
618 			 */
619 			error = -EBUSY;
620 		} else {
621 			hw->ccb_alloc[slot]->ccb_cnt++;
622 			error = 0;
623 		}
624 	}
625 out:
626 	spin_unlock(&hw->open_lock);
627 
628 	if (!error)
629 		fp->private_data = hw->ccb_alloc[slot];
630 
631 	return error;
632 }
633 
634 static const struct file_operations ilo_fops = {
635 	.owner		= THIS_MODULE,
636 	.read		= ilo_read,
637 	.write		= ilo_write,
638 	.poll		= ilo_poll,
639 	.open 		= ilo_open,
640 	.release 	= ilo_close,
641 	.llseek		= noop_llseek,
642 };
643 
644 static irqreturn_t ilo_isr(int irq, void *data)
645 {
646 	struct ilo_hwinfo *hw = data;
647 	int pending, i;
648 
649 	spin_lock(&hw->alloc_lock);
650 
651 	/* check for ccbs which have data */
652 	pending = get_device_outbound(hw);
653 	if (!pending) {
654 		spin_unlock(&hw->alloc_lock);
655 		return IRQ_NONE;
656 	}
657 
658 	if (is_db_reset(pending)) {
659 		/* wake up all ccbs if the device was reset */
660 		pending = -1;
661 		ilo_set_reset(hw);
662 	}
663 
664 	for (i = 0; i < max_ccb; i++) {
665 		if (!hw->ccb_alloc[i])
666 			continue;
667 		if (pending & (1 << i))
668 			wake_up_interruptible(&hw->ccb_alloc[i]->ccb_waitq);
669 	}
670 
671 	/* clear the device of the channels that have been handled */
672 	clear_pending_db(hw, pending);
673 
674 	spin_unlock(&hw->alloc_lock);
675 
676 	return IRQ_HANDLED;
677 }
678 
679 static void ilo_unmap_device(struct pci_dev *pdev, struct ilo_hwinfo *hw)
680 {
681 	pci_iounmap(pdev, hw->db_vaddr);
682 	pci_iounmap(pdev, hw->ram_vaddr);
683 	pci_iounmap(pdev, hw->mmio_vaddr);
684 }
685 
686 static int ilo_map_device(struct pci_dev *pdev, struct ilo_hwinfo *hw)
687 {
688 	int bar;
689 	unsigned long off;
690 
691 	/* map the memory mapped i/o registers */
692 	hw->mmio_vaddr = pci_iomap(pdev, 1, 0);
693 	if (hw->mmio_vaddr == NULL) {
694 		dev_err(&pdev->dev, "Error mapping mmio\n");
695 		goto out;
696 	}
697 
698 	/* map the adapter shared memory region */
699 	if (pdev->subsystem_device == 0x00E4) {
700 		bar = 5;
701 		/* Last 8k is reserved for CCBs */
702 		off = pci_resource_len(pdev, bar) - 0x2000;
703 	} else {
704 		bar = 2;
705 		off = 0;
706 	}
707 	hw->ram_vaddr = pci_iomap_range(pdev, bar, off, max_ccb * ILOHW_CCB_SZ);
708 	if (hw->ram_vaddr == NULL) {
709 		dev_err(&pdev->dev, "Error mapping shared mem\n");
710 		goto mmio_free;
711 	}
712 
713 	/* map the doorbell aperture */
714 	hw->db_vaddr = pci_iomap(pdev, 3, max_ccb * ONE_DB_SIZE);
715 	if (hw->db_vaddr == NULL) {
716 		dev_err(&pdev->dev, "Error mapping doorbell\n");
717 		goto ram_free;
718 	}
719 
720 	return 0;
721 ram_free:
722 	pci_iounmap(pdev, hw->ram_vaddr);
723 mmio_free:
724 	pci_iounmap(pdev, hw->mmio_vaddr);
725 out:
726 	return -ENOMEM;
727 }
728 
729 static void ilo_remove(struct pci_dev *pdev)
730 {
731 	int i, minor;
732 	struct ilo_hwinfo *ilo_hw = pci_get_drvdata(pdev);
733 
734 	if (!ilo_hw)
735 		return;
736 
737 	clear_device(ilo_hw);
738 
739 	minor = MINOR(ilo_hw->cdev.dev);
740 	for (i = minor; i < minor + max_ccb; i++)
741 		device_destroy(ilo_class, MKDEV(ilo_major, i));
742 
743 	cdev_del(&ilo_hw->cdev);
744 	ilo_disable_interrupts(ilo_hw);
745 	free_irq(pdev->irq, ilo_hw);
746 	ilo_unmap_device(pdev, ilo_hw);
747 	pci_release_regions(pdev);
748 	/*
749 	 * pci_disable_device(pdev) used to be here. But this PCI device has
750 	 * two functions with interrupt lines connected to a single pin. The
751 	 * other one is a USB host controller. So when we disable the PIN here
752 	 * e.g. by rmmod hpilo, the controller stops working. It is because
753 	 * the interrupt link is disabled in ACPI since it is not refcounted
754 	 * yet. See acpi_pci_link_free_irq called from acpi_pci_irq_disable.
755 	 */
756 	kfree(ilo_hw);
757 	ilo_hwdev[(minor / max_ccb)] = 0;
758 }
759 
760 static int ilo_probe(struct pci_dev *pdev,
761 			       const struct pci_device_id *ent)
762 {
763 	int devnum, minor, start, error = 0;
764 	struct ilo_hwinfo *ilo_hw;
765 
766 	/* Ignore subsystem_device = 0x1979 (set by BIOS)  */
767 	if (pdev->subsystem_device == 0x1979)
768 		return 0;
769 
770 	if (max_ccb > MAX_CCB)
771 		max_ccb = MAX_CCB;
772 	else if (max_ccb < MIN_CCB)
773 		max_ccb = MIN_CCB;
774 
775 	/* find a free range for device files */
776 	for (devnum = 0; devnum < MAX_ILO_DEV; devnum++) {
777 		if (ilo_hwdev[devnum] == 0) {
778 			ilo_hwdev[devnum] = 1;
779 			break;
780 		}
781 	}
782 
783 	if (devnum == MAX_ILO_DEV) {
784 		dev_err(&pdev->dev, "Error finding free device\n");
785 		return -ENODEV;
786 	}
787 
788 	/* track global allocations for this device */
789 	error = -ENOMEM;
790 	ilo_hw = kzalloc(sizeof(*ilo_hw), GFP_KERNEL);
791 	if (!ilo_hw)
792 		goto out;
793 
794 	ilo_hw->ilo_dev = pdev;
795 	spin_lock_init(&ilo_hw->alloc_lock);
796 	spin_lock_init(&ilo_hw->fifo_lock);
797 	spin_lock_init(&ilo_hw->open_lock);
798 
799 	error = pci_enable_device(pdev);
800 	if (error)
801 		goto free;
802 
803 	pci_set_master(pdev);
804 
805 	error = pci_request_regions(pdev, ILO_NAME);
806 	if (error)
807 		goto disable;
808 
809 	error = ilo_map_device(pdev, ilo_hw);
810 	if (error)
811 		goto free_regions;
812 
813 	pci_set_drvdata(pdev, ilo_hw);
814 	clear_device(ilo_hw);
815 
816 	error = request_irq(pdev->irq, ilo_isr, IRQF_SHARED, "hpilo", ilo_hw);
817 	if (error)
818 		goto unmap;
819 
820 	ilo_enable_interrupts(ilo_hw);
821 
822 	cdev_init(&ilo_hw->cdev, &ilo_fops);
823 	ilo_hw->cdev.owner = THIS_MODULE;
824 	start = devnum * max_ccb;
825 	error = cdev_add(&ilo_hw->cdev, MKDEV(ilo_major, start), max_ccb);
826 	if (error) {
827 		dev_err(&pdev->dev, "Could not add cdev\n");
828 		goto remove_isr;
829 	}
830 
831 	for (minor = 0 ; minor < max_ccb; minor++) {
832 		struct device *dev;
833 		dev = device_create(ilo_class, &pdev->dev,
834 				    MKDEV(ilo_major, minor), NULL,
835 				    "hpilo!d%dccb%d", devnum, minor);
836 		if (IS_ERR(dev))
837 			dev_err(&pdev->dev, "Could not create files\n");
838 	}
839 
840 	return 0;
841 remove_isr:
842 	ilo_disable_interrupts(ilo_hw);
843 	free_irq(pdev->irq, ilo_hw);
844 unmap:
845 	ilo_unmap_device(pdev, ilo_hw);
846 free_regions:
847 	pci_release_regions(pdev);
848 disable:
849 /*	pci_disable_device(pdev);  see comment in ilo_remove */
850 free:
851 	kfree(ilo_hw);
852 out:
853 	ilo_hwdev[devnum] = 0;
854 	return error;
855 }
856 
857 static const struct pci_device_id ilo_devices[] = {
858 	{ PCI_DEVICE(PCI_VENDOR_ID_COMPAQ, 0xB204) },
859 	{ PCI_DEVICE(PCI_VENDOR_ID_HP, 0x3307) },
860 	{ }
861 };
862 MODULE_DEVICE_TABLE(pci, ilo_devices);
863 
864 static struct pci_driver ilo_driver = {
865 	.name 	  = ILO_NAME,
866 	.id_table = ilo_devices,
867 	.probe 	  = ilo_probe,
868 	.remove   = ilo_remove,
869 };
870 
871 static int __init ilo_init(void)
872 {
873 	int error;
874 	dev_t dev;
875 
876 	ilo_class = class_create(THIS_MODULE, "iLO");
877 	if (IS_ERR(ilo_class)) {
878 		error = PTR_ERR(ilo_class);
879 		goto out;
880 	}
881 
882 	error = alloc_chrdev_region(&dev, 0, MAX_OPEN, ILO_NAME);
883 	if (error)
884 		goto class_destroy;
885 
886 	ilo_major = MAJOR(dev);
887 
888 	error =	pci_register_driver(&ilo_driver);
889 	if (error)
890 		goto chr_remove;
891 
892 	return 0;
893 chr_remove:
894 	unregister_chrdev_region(dev, MAX_OPEN);
895 class_destroy:
896 	class_destroy(ilo_class);
897 out:
898 	return error;
899 }
900 
901 static void __exit ilo_exit(void)
902 {
903 	pci_unregister_driver(&ilo_driver);
904 	unregister_chrdev_region(MKDEV(ilo_major, 0), MAX_OPEN);
905 	class_destroy(ilo_class);
906 }
907 
908 MODULE_VERSION("1.5.0");
909 MODULE_ALIAS(ILO_NAME);
910 MODULE_DESCRIPTION(ILO_NAME);
911 MODULE_AUTHOR("David Altobelli <david.altobelli@hpe.com>");
912 MODULE_LICENSE("GPL v2");
913 
914 module_param(max_ccb, uint, 0444);
915 MODULE_PARM_DESC(max_ccb, "Maximum number of HP iLO channels to attach (8-24)(default=16)");
916 
917 module_init(ilo_init);
918 module_exit(ilo_exit);
919