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 	ring->coal_param = q->handle->coal_param;
206 	assert(!ring->desc && !ring->desc_cb && !ring->desc_dma_addr);
207 
208 	/* not matter for tx or rx ring, the ntc and ntc start from 0 */
209 	assert(ring->next_to_use == 0);
210 	assert(ring->next_to_clean == 0);
211 
212 	ring->desc_cb = kcalloc(ring->desc_num, sizeof(ring->desc_cb[0]),
213 			GFP_KERNEL);
214 	if (!ring->desc_cb) {
215 		ret = -ENOMEM;
216 		goto out;
217 	}
218 
219 	ret = hnae_alloc_desc(ring);
220 	if (ret)
221 		goto out_with_desc_cb;
222 
223 	if (is_rx_ring(ring)) {
224 		ret = hnae_alloc_buffers(ring);
225 		if (ret)
226 			goto out_with_desc;
227 	}
228 
229 	return 0;
230 
231 out_with_desc:
232 	hnae_free_desc(ring);
233 out_with_desc_cb:
234 	kfree(ring->desc_cb);
235 	ring->desc_cb = NULL;
236 out:
237 	return ret;
238 }
239 
240 static int hnae_init_queue(struct hnae_handle *h, struct hnae_queue *q,
241 			   struct hnae_ae_dev *dev)
242 {
243 	int ret;
244 
245 	q->dev = dev;
246 	q->handle = h;
247 
248 	ret = hnae_init_ring(q, &q->tx_ring, q->tx_ring.flags | RINGF_DIR);
249 	if (ret)
250 		goto out;
251 
252 	ret = hnae_init_ring(q, &q->rx_ring, q->rx_ring.flags & ~RINGF_DIR);
253 	if (ret)
254 		goto out_with_tx_ring;
255 
256 	if (dev->ops->init_queue)
257 		dev->ops->init_queue(q);
258 
259 	return 0;
260 
261 out_with_tx_ring:
262 	hnae_fini_ring(&q->tx_ring);
263 out:
264 	return ret;
265 }
266 
267 static void hnae_fini_queue(struct hnae_queue *q)
268 {
269 	if (q->dev->ops->fini_queue)
270 		q->dev->ops->fini_queue(q);
271 
272 	hnae_fini_ring(&q->tx_ring);
273 	hnae_fini_ring(&q->rx_ring);
274 }
275 
276 /**
277  * ae_chain - define ae chain head
278  */
279 static RAW_NOTIFIER_HEAD(ae_chain);
280 
281 int hnae_register_notifier(struct notifier_block *nb)
282 {
283 	return raw_notifier_chain_register(&ae_chain, nb);
284 }
285 EXPORT_SYMBOL(hnae_register_notifier);
286 
287 void hnae_unregister_notifier(struct notifier_block *nb)
288 {
289 	if (raw_notifier_chain_unregister(&ae_chain, nb))
290 		dev_err(NULL, "notifier chain unregister fail\n");
291 }
292 EXPORT_SYMBOL(hnae_unregister_notifier);
293 
294 int hnae_reinit_handle(struct hnae_handle *handle)
295 {
296 	int i, j;
297 	int ret;
298 
299 	for (i = 0; i < handle->q_num; i++) /* free ring*/
300 		hnae_fini_queue(handle->qs[i]);
301 
302 	if (handle->dev->ops->reset)
303 		handle->dev->ops->reset(handle);
304 
305 	for (i = 0; i < handle->q_num; i++) {/* reinit ring*/
306 		ret = hnae_init_queue(handle, handle->qs[i], handle->dev);
307 		if (ret)
308 			goto out_when_init_queue;
309 	}
310 	return 0;
311 out_when_init_queue:
312 	for (j = i - 1; j >= 0; j--)
313 		hnae_fini_queue(handle->qs[j]);
314 	return ret;
315 }
316 EXPORT_SYMBOL(hnae_reinit_handle);
317 
318 /* hnae_get_handle - get a handle from the AE
319  * @owner_dev: the dev use this handle
320  * @ae_id: the id of the ae to be used
321  * @ae_opts: the options set for the handle
322  * @bops: the callbacks for buffer management
323  *
324  * return handle ptr or ERR_PTR
325  */
326 struct hnae_handle *hnae_get_handle(struct device *owner_dev,
327 				    const struct fwnode_handle	*fwnode,
328 				    u32 port_id,
329 				    struct hnae_buf_ops *bops)
330 {
331 	struct hnae_ae_dev *dev;
332 	struct hnae_handle *handle;
333 	int i, j;
334 	int ret;
335 
336 	dev = find_ae(fwnode);
337 	if (!dev)
338 		return ERR_PTR(-ENODEV);
339 
340 	handle = dev->ops->get_handle(dev, port_id);
341 	if (IS_ERR(handle)) {
342 		put_device(&dev->cls_dev);
343 		return handle;
344 	}
345 
346 	handle->dev = dev;
347 	handle->owner_dev = owner_dev;
348 	handle->bops = bops ? bops : &hnae_bops;
349 	handle->eport_id = port_id;
350 
351 	for (i = 0; i < handle->q_num; i++) {
352 		ret = hnae_init_queue(handle, handle->qs[i], dev);
353 		if (ret)
354 			goto out_when_init_queue;
355 	}
356 
357 	__module_get(dev->owner);
358 
359 	hnae_list_add(&dev->lock, &handle->node, &dev->handle_list);
360 
361 	return handle;
362 
363 out_when_init_queue:
364 	for (j = i - 1; j >= 0; j--)
365 		hnae_fini_queue(handle->qs[j]);
366 
367 	put_device(&dev->cls_dev);
368 
369 	return ERR_PTR(-ENOMEM);
370 }
371 EXPORT_SYMBOL(hnae_get_handle);
372 
373 void hnae_put_handle(struct hnae_handle *h)
374 {
375 	struct hnae_ae_dev *dev = h->dev;
376 	int i;
377 
378 	for (i = 0; i < h->q_num; i++)
379 		hnae_fini_queue(h->qs[i]);
380 
381 	if (h->dev->ops->reset)
382 		h->dev->ops->reset(h);
383 
384 	hnae_list_del(&dev->lock, &h->node);
385 
386 	if (dev->ops->put_handle)
387 		dev->ops->put_handle(h);
388 
389 	module_put(dev->owner);
390 
391 	put_device(&dev->cls_dev);
392 }
393 EXPORT_SYMBOL(hnae_put_handle);
394 
395 static void hnae_release(struct device *dev)
396 {
397 }
398 
399 /**
400  * hnae_ae_register - register a AE engine to hnae framework
401  * @hdev: the hnae ae engine device
402  * @owner:  the module who provides this dev
403  * NOTE: the duplicated name will not be checked
404  */
405 int hnae_ae_register(struct hnae_ae_dev *hdev, struct module *owner)
406 {
407 	static atomic_t id = ATOMIC_INIT(-1);
408 	int ret;
409 
410 	if (!hdev->dev)
411 		return -ENODEV;
412 
413 	if (!hdev->ops || !hdev->ops->get_handle ||
414 	    !hdev->ops->toggle_ring_irq ||
415 	    !hdev->ops->get_status || !hdev->ops->adjust_link)
416 		return -EINVAL;
417 
418 	hdev->owner = owner;
419 	hdev->id = (int)atomic_inc_return(&id);
420 	hdev->cls_dev.parent = hdev->dev;
421 	hdev->cls_dev.class = hnae_class;
422 	hdev->cls_dev.release = hnae_release;
423 	(void)dev_set_name(&hdev->cls_dev, "hnae%d", hdev->id);
424 	ret = device_register(&hdev->cls_dev);
425 	if (ret)
426 		return ret;
427 
428 	__module_get(THIS_MODULE);
429 
430 	INIT_LIST_HEAD(&hdev->handle_list);
431 	spin_lock_init(&hdev->lock);
432 
433 	ret = raw_notifier_call_chain(&ae_chain, HNAE_AE_REGISTER, NULL);
434 	if (ret)
435 		dev_dbg(hdev->dev,
436 			"has not notifier for AE: %s\n", hdev->name);
437 
438 	return 0;
439 }
440 EXPORT_SYMBOL(hnae_ae_register);
441 
442 /**
443  * hnae_ae_unregister - unregisters a HNAE AE engine
444  * @cdev: the device to unregister
445  */
446 void hnae_ae_unregister(struct hnae_ae_dev *hdev)
447 {
448 	device_unregister(&hdev->cls_dev);
449 	module_put(THIS_MODULE);
450 }
451 EXPORT_SYMBOL(hnae_ae_unregister);
452 
453 static int __init hnae_init(void)
454 {
455 	hnae_class = class_create(THIS_MODULE, "hnae");
456 	return PTR_ERR_OR_ZERO(hnae_class);
457 }
458 
459 static void __exit hnae_exit(void)
460 {
461 	class_destroy(hnae_class);
462 }
463 
464 subsys_initcall(hnae_init);
465 module_exit(hnae_exit);
466 
467 MODULE_AUTHOR("Hisilicon, Inc.");
468 MODULE_LICENSE("GPL");
469 MODULE_DESCRIPTION("Hisilicon Network Acceleration Engine Framework");
470 
471 /* vi: set tw=78 noet: */
472