2 * Intel MIC Platform Software Stack (MPSS)
4 * Copyright(c) 2013 Intel Corporation.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License, version 2, as
8 * published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
15 * The full GNU General Public License is included in this distribution in
16 * the file called "COPYING".
18 * Intel MIC Host driver.
21 #include <linux/pci.h>
22 #include <linux/interrupt.h>
24 #include "../common/mic_dev.h"
25 #include "mic_device.h"
28 * mic_invoke_callback - Invoke callback functions registered for
29 * the corresponding source id.
31 * @mdev: pointer to the mic_device instance
32 * @idx: The interrupt source id.
36 static inline void mic_invoke_callback(struct mic_device *mdev, int idx)
38 struct mic_intr_cb *intr_cb;
39 struct pci_dev *pdev = container_of(mdev->sdev->parent,
42 spin_lock(&mdev->irq_info.mic_intr_lock);
43 list_for_each_entry(intr_cb, &mdev->irq_info.cb_list[idx], list)
45 intr_cb->func(pdev->irq, intr_cb->data);
46 spin_unlock(&mdev->irq_info.mic_intr_lock);
50 * mic_interrupt - Generic interrupt handler for
51 * MSI and INTx based interrupts.
53 static irqreturn_t mic_interrupt(int irq, void *dev)
55 struct mic_device *mdev = dev;
56 struct mic_intr_info *info = mdev->intr_info;
60 mask = mdev->ops->ack_interrupt(mdev);
64 for (i = info->intr_start_idx[MIC_INTR_DB];
65 i < info->intr_len[MIC_INTR_DB]; i++)
67 mic_invoke_callback(mdev, i);
72 /* Return the interrupt offset from the index. Index is 0 based. */
73 static u16 mic_map_src_to_offset(struct mic_device *mdev,
74 int intr_src, enum mic_intr_type type) {
76 if (type >= MIC_NUM_INTR_TYPES)
77 return MIC_NUM_OFFSETS;
78 if (intr_src >= mdev->intr_info->intr_len[type])
79 return MIC_NUM_OFFSETS;
81 return mdev->intr_info->intr_start_idx[type] + intr_src;
84 /* Return next available msix_entry. */
85 static struct msix_entry *mic_get_available_vector(struct mic_device *mdev)
88 struct mic_irq_info *info = &mdev->irq_info;
90 for (i = 0; i < info->num_vectors; i++)
91 if (!info->mic_msi_map[i])
92 return &info->msix_entries[i];
97 * mic_register_intr_callback - Register a callback handler for the
100 * @mdev: pointer to the mic_device instance
101 * @idx: The source id to be registered.
102 * @func: The function to be called when the source id receives
104 * @data: Private data of the requester.
105 * Return the callback structure that was registered or an
106 * appropriate error on failure.
108 static struct mic_intr_cb *mic_register_intr_callback(struct mic_device *mdev,
109 u8 idx, irqreturn_t (*func) (int irq, void *dev),
112 struct mic_intr_cb *intr_cb;
115 intr_cb = kmalloc(sizeof(struct mic_intr_cb), GFP_KERNEL);
118 return ERR_PTR(-ENOMEM);
120 intr_cb->func = func;
121 intr_cb->data = data;
122 intr_cb->cb_id = ida_simple_get(&mdev->irq_info.cb_ida,
124 if (intr_cb->cb_id < 0) {
129 spin_lock_irqsave(&mdev->irq_info.mic_intr_lock, flags);
130 list_add_tail(&intr_cb->list, &mdev->irq_info.cb_list[idx]);
131 spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock, flags);
140 * mic_unregister_intr_callback - Unregister the callback handler
141 * identified by its callback id.
143 * @mdev: pointer to the mic_device instance
144 * @idx: The callback structure id to be unregistered.
145 * Return the source id that was unregistered or MIC_NUM_OFFSETS if no
146 * such callback handler was found.
148 static u8 mic_unregister_intr_callback(struct mic_device *mdev, u32 idx)
150 struct list_head *pos, *tmp;
151 struct mic_intr_cb *intr_cb;
155 for (i = 0; i < MIC_NUM_OFFSETS; i++) {
156 spin_lock_irqsave(&mdev->irq_info.mic_intr_lock, flags);
157 list_for_each_safe(pos, tmp, &mdev->irq_info.cb_list[i]) {
158 intr_cb = list_entry(pos, struct mic_intr_cb, list);
159 if (intr_cb->cb_id == idx) {
161 ida_simple_remove(&mdev->irq_info.cb_ida,
164 spin_unlock_irqrestore(
165 &mdev->irq_info.mic_intr_lock, flags);
169 spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock, flags);
171 return MIC_NUM_OFFSETS;
175 * mic_setup_msix - Initializes MSIx interrupts.
177 * @mdev: pointer to mic_device instance
180 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
182 static int mic_setup_msix(struct mic_device *mdev, struct pci_dev *pdev)
186 mdev->irq_info.msix_entries = kmalloc(sizeof(struct msix_entry) *
187 MIC_MIN_MSIX, GFP_KERNEL);
188 if (!mdev->irq_info.msix_entries) {
193 for (i = 0; i < MIC_MIN_MSIX; i++)
194 mdev->irq_info.msix_entries[i].entry = i;
196 rc = pci_enable_msix(pdev, mdev->irq_info.msix_entries,
199 dev_dbg(&pdev->dev, "Error enabling MSIx. rc = %d\n", rc);
200 goto err_enable_msix;
203 mdev->irq_info.num_vectors = MIC_MIN_MSIX;
204 mdev->irq_info.mic_msi_map = kzalloc((sizeof(u32) *
205 mdev->irq_info.num_vectors), GFP_KERNEL);
207 if (!mdev->irq_info.mic_msi_map) {
212 dev_dbg(mdev->sdev->parent,
213 "%d MSIx irqs setup\n", mdev->irq_info.num_vectors);
216 pci_disable_msix(pdev);
218 kfree(mdev->irq_info.msix_entries);
220 mdev->irq_info.num_vectors = 0;
225 * mic_setup_callbacks - Initialize data structures needed
226 * to handle callbacks.
228 * @mdev: pointer to mic_device instance
230 static int mic_setup_callbacks(struct mic_device *mdev)
234 mdev->irq_info.cb_list = kmalloc(sizeof(struct list_head) *
235 MIC_NUM_OFFSETS, GFP_KERNEL);
236 if (!mdev->irq_info.cb_list)
239 for (i = 0; i < MIC_NUM_OFFSETS; i++)
240 INIT_LIST_HEAD(&mdev->irq_info.cb_list[i]);
241 ida_init(&mdev->irq_info.cb_ida);
242 spin_lock_init(&mdev->irq_info.mic_intr_lock);
247 * mic_release_callbacks - Uninitialize data structures needed
248 * to handle callbacks.
250 * @mdev: pointer to mic_device instance
252 static void mic_release_callbacks(struct mic_device *mdev)
255 struct list_head *pos, *tmp;
256 struct mic_intr_cb *intr_cb;
259 for (i = 0; i < MIC_NUM_OFFSETS; i++) {
260 spin_lock_irqsave(&mdev->irq_info.mic_intr_lock, flags);
262 if (list_empty(&mdev->irq_info.cb_list[i])) {
263 spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock,
268 list_for_each_safe(pos, tmp, &mdev->irq_info.cb_list[i]) {
269 intr_cb = list_entry(pos, struct mic_intr_cb, list);
271 ida_simple_remove(&mdev->irq_info.cb_ida,
275 spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock, flags);
277 ida_destroy(&mdev->irq_info.cb_ida);
278 kfree(mdev->irq_info.cb_list);
282 * mic_setup_msi - Initializes MSI interrupts.
284 * @mdev: pointer to mic_device instance
285 * @pdev: PCI device structure
287 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
289 static int mic_setup_msi(struct mic_device *mdev, struct pci_dev *pdev)
293 rc = pci_enable_msi(pdev);
295 dev_dbg(&pdev->dev, "Error enabling MSI. rc = %d\n", rc);
299 mdev->irq_info.num_vectors = 1;
300 mdev->irq_info.mic_msi_map = kzalloc((sizeof(u32) *
301 mdev->irq_info.num_vectors), GFP_KERNEL);
303 if (!mdev->irq_info.mic_msi_map) {
308 rc = mic_setup_callbacks(mdev);
310 dev_err(&pdev->dev, "Error setting up callbacks\n");
314 rc = request_irq(pdev->irq, mic_interrupt, 0 , "mic-msi", mdev);
316 dev_err(&pdev->dev, "Error allocating MSI interrupt\n");
317 goto err_irq_req_fail;
320 dev_dbg(&pdev->dev, "%d MSI irqs setup\n", mdev->irq_info.num_vectors);
323 mic_release_callbacks(mdev);
325 kfree(mdev->irq_info.mic_msi_map);
327 pci_disable_msi(pdev);
328 mdev->irq_info.num_vectors = 0;
333 * mic_setup_intx - Initializes legacy interrupts.
335 * @mdev: pointer to mic_device instance
336 * @pdev: PCI device structure
338 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
340 static int mic_setup_intx(struct mic_device *mdev, struct pci_dev *pdev)
348 rc = mic_setup_callbacks(mdev);
350 dev_err(&pdev->dev, "Error setting up callbacks\n");
354 rc = request_irq(pdev->irq, mic_interrupt,
355 IRQF_SHARED, "mic-intx", mdev);
359 dev_dbg(&pdev->dev, "intx irq setup\n");
362 mic_release_callbacks(mdev);
368 * mic_next_db - Retrieve the next doorbell interrupt source id.
369 * The id is picked sequentially from the available pool of
372 * @mdev: pointer to the mic_device instance.
374 * Returns the next doorbell interrupt source.
376 int mic_next_db(struct mic_device *mdev)
380 next_db = mdev->irq_info.next_avail_src %
381 mdev->intr_info->intr_len[MIC_INTR_DB];
382 mdev->irq_info.next_avail_src++;
386 #define COOKIE_ID_SHIFT 16
387 #define GET_ENTRY(cookie) ((cookie) & 0xFFFF)
388 #define GET_OFFSET(cookie) ((cookie) >> COOKIE_ID_SHIFT)
389 #define MK_COOKIE(x, y) ((x) | (y) << COOKIE_ID_SHIFT)
392 * mic_request_irq - request an irq. mic_mutex needs
393 * to be held before calling this function.
395 * @mdev: pointer to mic_device instance
396 * @func: The callback function that handles the interrupt.
397 * The function needs to call ack_interrupts
398 * (mdev->ops->ack_interrupt(mdev)) when handling the interrupts.
399 * @name: The ASCII name of the callee requesting the irq.
400 * @data: private data that is returned back when calling the
402 * @intr_src: The source id of the requester. Its the doorbell id
403 * for Doorbell interrupts and DMA channel id for DMA interrupts.
404 * @type: The type of interrupt. Values defined in mic_intr_type
406 * returns: The cookie that is transparent to the caller. Passed
407 * back when calling mic_free_irq. An appropriate error code
408 * is returned on failure. Caller needs to use IS_ERR(return_val)
409 * to check for failure and PTR_ERR(return_val) to obtained the
413 struct mic_irq *mic_request_irq(struct mic_device *mdev,
414 irqreturn_t (*func)(int irq, void *dev),
415 const char *name, void *data, int intr_src,
416 enum mic_intr_type type)
420 struct msix_entry *msix = NULL;
421 unsigned long cookie = 0;
423 struct mic_intr_cb *intr_cb;
424 struct pci_dev *pdev = container_of(mdev->sdev->parent,
425 struct pci_dev, dev);
427 offset = mic_map_src_to_offset(mdev, intr_src, type);
428 if (offset >= MIC_NUM_OFFSETS) {
429 dev_err(mdev->sdev->parent,
430 "Error mapping index %d to a valid source id.\n",
436 if (mdev->irq_info.num_vectors > 1) {
437 msix = mic_get_available_vector(mdev);
439 dev_err(mdev->sdev->parent,
440 "No MSIx vectors available for use.\n");
445 rc = request_irq(msix->vector, func, 0, name, data);
447 dev_dbg(mdev->sdev->parent,
448 "request irq failed rc = %d\n", rc);
452 mdev->irq_info.mic_msi_map[entry] |= BIT(offset);
453 mdev->intr_ops->program_msi_to_src_map(mdev,
454 entry, offset, true);
455 cookie = MK_COOKIE(entry, offset);
456 dev_dbg(mdev->sdev->parent, "irq: %d assigned for src: %d\n",
457 msix->vector, intr_src);
459 intr_cb = mic_register_intr_callback(mdev,
461 if (IS_ERR(intr_cb)) {
462 dev_err(mdev->sdev->parent,
463 "No available callback entries for use\n");
464 rc = PTR_ERR(intr_cb);
469 if (pci_dev_msi_enabled(pdev)) {
470 mdev->irq_info.mic_msi_map[entry] |= (1 << offset);
471 mdev->intr_ops->program_msi_to_src_map(mdev,
472 entry, offset, true);
474 cookie = MK_COOKIE(entry, intr_cb->cb_id);
475 dev_dbg(mdev->sdev->parent, "callback %d registered for src: %d\n",
476 intr_cb->cb_id, intr_src);
478 return (struct mic_irq *)cookie;
484 * mic_free_irq - free irq. mic_mutex
485 * needs to be held before calling this function.
487 * @mdev: pointer to mic_device instance
488 * @cookie: cookie obtained during a successful call to mic_request_irq
489 * @data: private data specified by the calling function during the
494 void mic_free_irq(struct mic_device *mdev,
495 struct mic_irq *cookie, void *data)
501 struct pci_dev *pdev = container_of(mdev->sdev->parent,
502 struct pci_dev, dev);
504 entry = GET_ENTRY((unsigned long)cookie);
505 offset = GET_OFFSET((unsigned long)cookie);
506 if (mdev->irq_info.num_vectors > 1) {
507 if (entry >= mdev->irq_info.num_vectors) {
508 dev_warn(mdev->sdev->parent,
509 "entry %d should be < num_irq %d\n",
510 entry, mdev->irq_info.num_vectors);
513 irq = mdev->irq_info.msix_entries[entry].vector;
515 mdev->irq_info.mic_msi_map[entry] &= ~(BIT(offset));
516 mdev->intr_ops->program_msi_to_src_map(mdev,
517 entry, offset, false);
519 dev_dbg(mdev->sdev->parent, "irq: %d freed\n", irq);
522 src_id = mic_unregister_intr_callback(mdev, offset);
523 if (src_id >= MIC_NUM_OFFSETS) {
524 dev_warn(mdev->sdev->parent, "Error unregistering callback\n");
527 if (pci_dev_msi_enabled(pdev)) {
528 mdev->irq_info.mic_msi_map[entry] &= ~(BIT(src_id));
529 mdev->intr_ops->program_msi_to_src_map(mdev,
530 entry, src_id, false);
532 dev_dbg(mdev->sdev->parent, "callback %d unregistered for src: %d\n",
538 * mic_setup_interrupts - Initializes interrupts.
540 * @mdev: pointer to mic_device instance
541 * @pdev: PCI device structure
543 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
545 int mic_setup_interrupts(struct mic_device *mdev, struct pci_dev *pdev)
549 rc = mic_setup_msix(mdev, pdev);
553 rc = mic_setup_msi(mdev, pdev);
557 rc = mic_setup_intx(mdev, pdev);
559 dev_err(mdev->sdev->parent, "no usable interrupts\n");
563 mdev->intr_ops->enable_interrupts(mdev);
568 * mic_free_interrupts - Frees interrupts setup by mic_setup_interrupts
570 * @mdev: pointer to mic_device instance
571 * @pdev: PCI device structure
575 void mic_free_interrupts(struct mic_device *mdev, struct pci_dev *pdev)
579 mdev->intr_ops->disable_interrupts(mdev);
580 if (mdev->irq_info.num_vectors > 1) {
581 for (i = 0; i < mdev->irq_info.num_vectors; i++) {
582 if (mdev->irq_info.mic_msi_map[i])
583 dev_warn(&pdev->dev, "irq %d may still be in use.\n",
584 mdev->irq_info.msix_entries[i].vector);
586 kfree(mdev->irq_info.mic_msi_map);
587 kfree(mdev->irq_info.msix_entries);
588 pci_disable_msix(pdev);
590 if (pci_dev_msi_enabled(pdev)) {
591 free_irq(pdev->irq, mdev);
592 kfree(mdev->irq_info.mic_msi_map);
593 pci_disable_msi(pdev);
595 free_irq(pdev->irq, mdev);
597 mic_release_callbacks(mdev);
602 * mic_intr_restore - Restore MIC interrupt registers.
604 * @mdev: pointer to mic_device instance.
606 * Restore the interrupt registers to values previously
607 * stored in the SW data structures. mic_mutex needs to
608 * be held before calling this function.
612 void mic_intr_restore(struct mic_device *mdev)
615 struct pci_dev *pdev = container_of(mdev->sdev->parent,
616 struct pci_dev, dev);
618 if (!pci_dev_msi_enabled(pdev))
621 for (entry = 0; entry < mdev->irq_info.num_vectors; entry++) {
622 for (offset = 0; offset < MIC_NUM_OFFSETS; offset++) {
623 if (mdev->irq_info.mic_msi_map[entry] & BIT(offset))
624 mdev->intr_ops->program_msi_to_src_map(mdev,
625 entry, offset, true);