1 /*
2  * Copyright (c) 2014-2015 Hisilicon Limited.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  */
9 
10 #include <linux/dma-mapping.h>
11 #include <linux/interrupt.h>
12 #include <linux/of.h>
13 #include <linux/skbuff.h>
14 #include <linux/slab.h>
15 #include "hnae.h"
16 
17 #define cls_to_ae_dev(dev) container_of(dev, struct hnae_ae_dev, cls_dev)
18 
19 static struct class *hnae_class;
20 
21 static void
22 hnae_list_add(spinlock_t *lock, struct list_head *node, struct list_head *head)
23 {
24 	unsigned long flags;
25 
26 	spin_lock_irqsave(lock, flags);
27 	list_add_tail_rcu(node, head);
28 	spin_unlock_irqrestore(lock, flags);
29 }
30 
31 static void hnae_list_del(spinlock_t *lock, struct list_head *node)
32 {
33 	unsigned long flags;
34 
35 	spin_lock_irqsave(lock, flags);
36 	list_del_rcu(node);
37 	spin_unlock_irqrestore(lock, flags);
38 }
39 
40 static int hnae_alloc_buffer(struct hnae_ring *ring, struct hnae_desc_cb *cb)
41 {
42 	unsigned int order = hnae_page_order(ring);
43 	struct page *p = dev_alloc_pages(order);
44 
45 	if (!p)
46 		return -ENOMEM;
47 
48 	cb->priv = p;
49 	cb->page_offset = 0;
50 	cb->reuse_flag = 0;
51 	cb->buf  = page_address(p);
52 	cb->length = hnae_page_size(ring);
53 	cb->type = DESC_TYPE_PAGE;
54 
55 	return 0;
56 }
57 
58 static void hnae_free_buffer(struct hnae_ring *ring, struct hnae_desc_cb *cb)
59 {
60 	if (unlikely(!cb->priv))
61 		return;
62 
63 	if (cb->type == DESC_TYPE_SKB)
64 		dev_kfree_skb_any((struct sk_buff *)cb->priv);
65 	else if (unlikely(is_rx_ring(ring)))
66 		put_page((struct page *)cb->priv);
67 
68 	cb->priv = NULL;
69 }
70 
71 static int hnae_map_buffer(struct hnae_ring *ring, struct hnae_desc_cb *cb)
72 {
73 	cb->dma = dma_map_page(ring_to_dev(ring), cb->priv, 0,
74 			       cb->length, ring_to_dma_dir(ring));
75 
76 	if (dma_mapping_error(ring_to_dev(ring), cb->dma))
77 		return -EIO;
78 
79 	return 0;
80 }
81 
82 static void hnae_unmap_buffer(struct hnae_ring *ring, struct hnae_desc_cb *cb)
83 {
84 	if (cb->type == DESC_TYPE_SKB)
85 		dma_unmap_single(ring_to_dev(ring), cb->dma, cb->length,
86 				 ring_to_dma_dir(ring));
87 	else
88 		dma_unmap_page(ring_to_dev(ring), cb->dma, cb->length,
89 			       ring_to_dma_dir(ring));
90 }
91 
92 static struct hnae_buf_ops hnae_bops = {
93 	.alloc_buffer = hnae_alloc_buffer,
94 	.free_buffer = hnae_free_buffer,
95 	.map_buffer = hnae_map_buffer,
96 	.unmap_buffer = hnae_unmap_buffer,
97 };
98 
99 static int __ae_match(struct device *dev, const void *data)
100 {
101 	struct hnae_ae_dev *hdev = cls_to_ae_dev(dev);
102 
103 	if (dev_of_node(hdev->dev))
104 		return (data == &hdev->dev->of_node->fwnode);
105 	else if (is_acpi_node(hdev->dev->fwnode))
106 		return (data == hdev->dev->fwnode);
107 
108 	dev_err(dev, "__ae_match cannot read cfg data from OF or acpi\n");
109 	return 0;
110 }
111 
112 static struct hnae_ae_dev *find_ae(const struct fwnode_handle *fwnode)
113 {
114 	struct device *dev;
115 
116 	WARN_ON(!fwnode);
117 
118 	dev = class_find_device(hnae_class, NULL, fwnode, __ae_match);
119 
120 	return dev ? cls_to_ae_dev(dev) : NULL;
121 }
122 
123 static void hnae_free_buffers(struct hnae_ring *ring)
124 {
125 	int i;
126 
127 	for (i = 0; i < ring->desc_num; i++)
128 		hnae_free_buffer_detach(ring, i);
129 }
130 
131 /* Allocate memory for raw pkg, and map with dma */
132 static int hnae_alloc_buffers(struct hnae_ring *ring)
133 {
134 	int i, j, ret;
135 
136 	for (i = 0; i < ring->desc_num; i++) {
137 		ret = hnae_alloc_buffer_attach(ring, i);
138 		if (ret)
139 			goto out_buffer_fail;
140 	}
141 
142 	return 0;
143 
144 out_buffer_fail:
145 	for (j = i - 1; j >= 0; j--)
146 		hnae_free_buffer_detach(ring, j);
147 	return ret;
148 }
149 
150 /* free desc along with its attached buffer */
151 static void hnae_free_desc(struct hnae_ring *ring)
152 {
153 	hnae_free_buffers(ring);
154 	dma_unmap_single(ring_to_dev(ring), ring->desc_dma_addr,
155 			 ring->desc_num * sizeof(ring->desc[0]),
156 			 ring_to_dma_dir(ring));
157 	ring->desc_dma_addr = 0;
158 	kfree(ring->desc);
159 	ring->desc = NULL;
160 }
161 
162 /* alloc desc, without buffer attached */
163 static int hnae_alloc_desc(struct hnae_ring *ring)
164 {
165 	int size = ring->desc_num * sizeof(ring->desc[0]);
166 
167 	ring->desc = kzalloc(size, GFP_KERNEL);
168 	if (!ring->desc)
169 		return -ENOMEM;
170 
171 	ring->desc_dma_addr = dma_map_single(ring_to_dev(ring),
172 		ring->desc, size, ring_to_dma_dir(ring));
173 	if (dma_mapping_error(ring_to_dev(ring), ring->desc_dma_addr)) {
174 		ring->desc_dma_addr = 0;
175 		kfree(ring->desc);
176 		ring->desc = NULL;
177 		return -ENOMEM;
178 	}
179 
180 	return 0;
181 }
182 
183 /* fini ring, also free the buffer for the ring */
184 static void hnae_fini_ring(struct hnae_ring *ring)
185 {
186 	hnae_free_desc(ring);
187 	kfree(ring->desc_cb);
188 	ring->desc_cb = NULL;
189 	ring->next_to_clean = 0;
190 	ring->next_to_use = 0;
191 }
192 
193 /* init ring, and with buffer for rx ring */
194 static int
195 hnae_init_ring(struct hnae_queue *q, struct hnae_ring *ring, int flags)
196 {
197 	int ret;
198 
199 	if (ring->desc_num <= 0 || ring->buf_size <= 0)
200 		return -EINVAL;
201 
202 	ring->q = q;
203 	ring->flags = flags;
204 	spin_lock_init(&ring->lock);
205 	assert(!ring->desc && !ring->desc_cb && !ring->desc_dma_addr);
206 
207 	/* not matter for tx or rx ring, the ntc and ntc start from 0 */
208 	assert(ring->next_to_use == 0);
209 	assert(ring->next_to_clean == 0);
210 
211 	ring->desc_cb = kcalloc(ring->desc_num, sizeof(ring->desc_cb[0]),
212 			GFP_KERNEL);
213 	if (!ring->desc_cb) {
214 		ret = -ENOMEM;
215 		goto out;
216 	}
217 
218 	ret = hnae_alloc_desc(ring);
219 	if (ret)
220 		goto out_with_desc_cb;
221 
222 	if (is_rx_ring(ring)) {
223 		ret = hnae_alloc_buffers(ring);
224 		if (ret)
225 			goto out_with_desc;
226 	}
227 
228 	return 0;
229 
230 out_with_desc:
231 	hnae_free_desc(ring);
232 out_with_desc_cb:
233 	kfree(ring->desc_cb);
234 	ring->desc_cb = NULL;
235 out:
236 	return ret;
237 }
238 
239 static int hnae_init_queue(struct hnae_handle *h, struct hnae_queue *q,
240 			   struct hnae_ae_dev *dev)
241 {
242 	int ret;
243 
244 	q->dev = dev;
245 	q->handle = h;
246 
247 	ret = hnae_init_ring(q, &q->tx_ring, q->tx_ring.flags | RINGF_DIR);
248 	if (ret)
249 		goto out;
250 
251 	ret = hnae_init_ring(q, &q->rx_ring, q->rx_ring.flags & ~RINGF_DIR);
252 	if (ret)
253 		goto out_with_tx_ring;
254 
255 	if (dev->ops->init_queue)
256 		dev->ops->init_queue(q);
257 
258 	return 0;
259 
260 out_with_tx_ring:
261 	hnae_fini_ring(&q->tx_ring);
262 out:
263 	return ret;
264 }
265 
266 static void hnae_fini_queue(struct hnae_queue *q)
267 {
268 	if (q->dev->ops->fini_queue)
269 		q->dev->ops->fini_queue(q);
270 
271 	hnae_fini_ring(&q->tx_ring);
272 	hnae_fini_ring(&q->rx_ring);
273 }
274 
275 /**
276  * ae_chain - define ae chain head
277  */
278 static RAW_NOTIFIER_HEAD(ae_chain);
279 
280 int hnae_register_notifier(struct notifier_block *nb)
281 {
282 	return raw_notifier_chain_register(&ae_chain, nb);
283 }
284 EXPORT_SYMBOL(hnae_register_notifier);
285 
286 void hnae_unregister_notifier(struct notifier_block *nb)
287 {
288 	if (raw_notifier_chain_unregister(&ae_chain, nb))
289 		dev_err(NULL, "notifier chain unregister fail\n");
290 }
291 EXPORT_SYMBOL(hnae_unregister_notifier);
292 
293 int hnae_reinit_handle(struct hnae_handle *handle)
294 {
295 	int i, j;
296 	int ret;
297 
298 	for (i = 0; i < handle->q_num; i++) /* free ring*/
299 		hnae_fini_queue(handle->qs[i]);
300 
301 	if (handle->dev->ops->reset)
302 		handle->dev->ops->reset(handle);
303 
304 	for (i = 0; i < handle->q_num; i++) {/* reinit ring*/
305 		ret = hnae_init_queue(handle, handle->qs[i], handle->dev);
306 		if (ret)
307 			goto out_when_init_queue;
308 	}
309 	return 0;
310 out_when_init_queue:
311 	for (j = i - 1; j >= 0; j--)
312 		hnae_fini_queue(handle->qs[j]);
313 	return ret;
314 }
315 EXPORT_SYMBOL(hnae_reinit_handle);
316 
317 /* hnae_get_handle - get a handle from the AE
318  * @owner_dev: the dev use this handle
319  * @ae_id: the id of the ae to be used
320  * @ae_opts: the options set for the handle
321  * @bops: the callbacks for buffer management
322  *
323  * return handle ptr or ERR_PTR
324  */
325 struct hnae_handle *hnae_get_handle(struct device *owner_dev,
326 				    const struct fwnode_handle	*fwnode,
327 				    u32 port_id,
328 				    struct hnae_buf_ops *bops)
329 {
330 	struct hnae_ae_dev *dev;
331 	struct hnae_handle *handle;
332 	int i, j;
333 	int ret;
334 
335 	dev = find_ae(fwnode);
336 	if (!dev)
337 		return ERR_PTR(-ENODEV);
338 
339 	handle = dev->ops->get_handle(dev, port_id);
340 	if (IS_ERR(handle)) {
341 		put_device(&dev->cls_dev);
342 		return handle;
343 	}
344 
345 	handle->dev = dev;
346 	handle->owner_dev = owner_dev;
347 	handle->bops = bops ? bops : &hnae_bops;
348 	handle->eport_id = port_id;
349 
350 	for (i = 0; i < handle->q_num; i++) {
351 		ret = hnae_init_queue(handle, handle->qs[i], dev);
352 		if (ret)
353 			goto out_when_init_queue;
354 	}
355 
356 	__module_get(dev->owner);
357 
358 	hnae_list_add(&dev->lock, &handle->node, &dev->handle_list);
359 
360 	return handle;
361 
362 out_when_init_queue:
363 	for (j = i - 1; j >= 0; j--)
364 		hnae_fini_queue(handle->qs[j]);
365 
366 	put_device(&dev->cls_dev);
367 
368 	return ERR_PTR(-ENOMEM);
369 }
370 EXPORT_SYMBOL(hnae_get_handle);
371 
372 void hnae_put_handle(struct hnae_handle *h)
373 {
374 	struct hnae_ae_dev *dev = h->dev;
375 	int i;
376 
377 	for (i = 0; i < h->q_num; i++)
378 		hnae_fini_queue(h->qs[i]);
379 
380 	if (h->dev->ops->reset)
381 		h->dev->ops->reset(h);
382 
383 	hnae_list_del(&dev->lock, &h->node);
384 
385 	if (dev->ops->put_handle)
386 		dev->ops->put_handle(h);
387 
388 	module_put(dev->owner);
389 
390 	put_device(&dev->cls_dev);
391 }
392 EXPORT_SYMBOL(hnae_put_handle);
393 
394 static void hnae_release(struct device *dev)
395 {
396 }
397 
398 /**
399  * hnae_ae_register - register a AE engine to hnae framework
400  * @hdev: the hnae ae engine device
401  * @owner:  the module who provides this dev
402  * NOTE: the duplicated name will not be checked
403  */
404 int hnae_ae_register(struct hnae_ae_dev *hdev, struct module *owner)
405 {
406 	static atomic_t id = ATOMIC_INIT(-1);
407 	int ret;
408 
409 	if (!hdev->dev)
410 		return -ENODEV;
411 
412 	if (!hdev->ops || !hdev->ops->get_handle ||
413 	    !hdev->ops->toggle_ring_irq ||
414 	    !hdev->ops->get_status || !hdev->ops->adjust_link)
415 		return -EINVAL;
416 
417 	hdev->owner = owner;
418 	hdev->id = (int)atomic_inc_return(&id);
419 	hdev->cls_dev.parent = hdev->dev;
420 	hdev->cls_dev.class = hnae_class;
421 	hdev->cls_dev.release = hnae_release;
422 	(void)dev_set_name(&hdev->cls_dev, "hnae%d", hdev->id);
423 	ret = device_register(&hdev->cls_dev);
424 	if (ret)
425 		return ret;
426 
427 	__module_get(THIS_MODULE);
428 
429 	INIT_LIST_HEAD(&hdev->handle_list);
430 	spin_lock_init(&hdev->lock);
431 
432 	ret = raw_notifier_call_chain(&ae_chain, HNAE_AE_REGISTER, NULL);
433 	if (ret)
434 		dev_dbg(hdev->dev,
435 			"has not notifier for AE: %s\n", hdev->name);
436 
437 	return 0;
438 }
439 EXPORT_SYMBOL(hnae_ae_register);
440 
441 /**
442  * hnae_ae_unregister - unregisters a HNAE AE engine
443  * @cdev: the device to unregister
444  */
445 void hnae_ae_unregister(struct hnae_ae_dev *hdev)
446 {
447 	device_unregister(&hdev->cls_dev);
448 	module_put(THIS_MODULE);
449 }
450 EXPORT_SYMBOL(hnae_ae_unregister);
451 
452 static int __init hnae_init(void)
453 {
454 	hnae_class = class_create(THIS_MODULE, "hnae");
455 	return PTR_ERR_OR_ZERO(hnae_class);
456 }
457 
458 static void __exit hnae_exit(void)
459 {
460 	class_destroy(hnae_class);
461 }
462 
463 subsys_initcall(hnae_init);
464 module_exit(hnae_exit);
465 
466 MODULE_AUTHOR("Hisilicon, Inc.");
467 MODULE_LICENSE("GPL");
468 MODULE_DESCRIPTION("Hisilicon Network Acceleration Engine Framework");
469 
470 /* vi: set tw=78 noet: */
471