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