xref: /linux/drivers/net/ethernet/marvell/mvneta_bm.c (revision dc35a10f68d3781c2345d60b22103785985ca849)
1 /*
2  * Driver for Marvell NETA network controller Buffer Manager.
3  *
4  * Copyright (C) 2015 Marvell
5  *
6  * Marcin Wojtas <mw@semihalf.com>
7  *
8  * This file is licensed under the terms of the GNU General Public
9  * License version 2. This program is licensed "as is" without any
10  * warranty of any kind, whether express or implied.
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/genalloc.h>
15 #include <linux/platform_device.h>
16 #include <linux/netdevice.h>
17 #include <linux/skbuff.h>
18 #include <linux/mbus.h>
19 #include <linux/module.h>
20 #include <linux/io.h>
21 #include <linux/of.h>
22 #include <linux/clk.h>
23 #include "mvneta_bm.h"
24 
25 #define MVNETA_BM_DRIVER_NAME "mvneta_bm"
26 #define MVNETA_BM_DRIVER_VERSION "1.0"
27 
28 static void mvneta_bm_write(struct mvneta_bm *priv, u32 offset, u32 data)
29 {
30 	writel(data, priv->reg_base + offset);
31 }
32 
33 static u32 mvneta_bm_read(struct mvneta_bm *priv, u32 offset)
34 {
35 	return readl(priv->reg_base + offset);
36 }
37 
38 static void mvneta_bm_pool_enable(struct mvneta_bm *priv, int pool_id)
39 {
40 	u32 val;
41 
42 	val = mvneta_bm_read(priv, MVNETA_BM_POOL_BASE_REG(pool_id));
43 	val |= MVNETA_BM_POOL_ENABLE_MASK;
44 	mvneta_bm_write(priv, MVNETA_BM_POOL_BASE_REG(pool_id), val);
45 
46 	/* Clear BM cause register */
47 	mvneta_bm_write(priv, MVNETA_BM_INTR_CAUSE_REG, 0);
48 }
49 
50 static void mvneta_bm_pool_disable(struct mvneta_bm *priv, int pool_id)
51 {
52 	u32 val;
53 
54 	val = mvneta_bm_read(priv, MVNETA_BM_POOL_BASE_REG(pool_id));
55 	val &= ~MVNETA_BM_POOL_ENABLE_MASK;
56 	mvneta_bm_write(priv, MVNETA_BM_POOL_BASE_REG(pool_id), val);
57 }
58 
59 static inline void mvneta_bm_config_set(struct mvneta_bm *priv, u32 mask)
60 {
61 	u32 val;
62 
63 	val = mvneta_bm_read(priv, MVNETA_BM_CONFIG_REG);
64 	val |= mask;
65 	mvneta_bm_write(priv, MVNETA_BM_CONFIG_REG, val);
66 }
67 
68 static inline void mvneta_bm_config_clear(struct mvneta_bm *priv, u32 mask)
69 {
70 	u32 val;
71 
72 	val = mvneta_bm_read(priv, MVNETA_BM_CONFIG_REG);
73 	val &= ~mask;
74 	mvneta_bm_write(priv, MVNETA_BM_CONFIG_REG, val);
75 }
76 
77 static void mvneta_bm_pool_target_set(struct mvneta_bm *priv, int pool_id,
78 				      u8 target_id, u8 attr)
79 {
80 	u32 val;
81 
82 	val = mvneta_bm_read(priv, MVNETA_BM_XBAR_POOL_REG(pool_id));
83 	val &= ~MVNETA_BM_TARGET_ID_MASK(pool_id);
84 	val &= ~MVNETA_BM_XBAR_ATTR_MASK(pool_id);
85 	val |= MVNETA_BM_TARGET_ID_VAL(pool_id, target_id);
86 	val |= MVNETA_BM_XBAR_ATTR_VAL(pool_id, attr);
87 
88 	mvneta_bm_write(priv, MVNETA_BM_XBAR_POOL_REG(pool_id), val);
89 }
90 
91 /* Allocate skb for BM pool */
92 void *mvneta_buf_alloc(struct mvneta_bm *priv, struct mvneta_bm_pool *bm_pool,
93 		       dma_addr_t *buf_phys_addr)
94 {
95 	void *buf;
96 	dma_addr_t phys_addr;
97 
98 	buf = mvneta_frag_alloc(bm_pool->frag_size);
99 	if (!buf)
100 		return NULL;
101 
102 	/* In order to update buf_cookie field of RX descriptor properly,
103 	 * BM hardware expects buf virtual address to be placed in the
104 	 * first four bytes of mapped buffer.
105 	 */
106 	*(u32 *)buf = (u32)buf;
107 	phys_addr = dma_map_single(&priv->pdev->dev, buf, bm_pool->buf_size,
108 				   DMA_FROM_DEVICE);
109 	if (unlikely(dma_mapping_error(&priv->pdev->dev, phys_addr))) {
110 		mvneta_frag_free(bm_pool->frag_size, buf);
111 		return NULL;
112 	}
113 	*buf_phys_addr = phys_addr;
114 
115 	return buf;
116 }
117 
118 /* Refill processing for HW buffer management */
119 int mvneta_bm_pool_refill(struct mvneta_bm *priv,
120 			  struct mvneta_bm_pool *bm_pool)
121 {
122 	dma_addr_t buf_phys_addr;
123 	void *buf;
124 
125 	buf = mvneta_buf_alloc(priv, bm_pool, &buf_phys_addr);
126 	if (!buf)
127 		return -ENOMEM;
128 
129 	mvneta_bm_pool_put_bp(priv, bm_pool, buf_phys_addr);
130 
131 	return 0;
132 }
133 EXPORT_SYMBOL_GPL(mvneta_bm_pool_refill);
134 
135 /* Allocate buffers for the pool */
136 int mvneta_bm_bufs_add(struct mvneta_bm *priv, struct mvneta_bm_pool *bm_pool,
137 		       int buf_num)
138 {
139 	int err, i;
140 
141 	if (bm_pool->buf_num == bm_pool->size) {
142 		dev_dbg(&priv->pdev->dev, "pool %d already filled\n",
143 			bm_pool->id);
144 		return bm_pool->buf_num;
145 	}
146 
147 	if (buf_num < 0 ||
148 	    (buf_num + bm_pool->buf_num > bm_pool->size)) {
149 		dev_err(&priv->pdev->dev,
150 			"cannot allocate %d buffers for pool %d\n",
151 			buf_num, bm_pool->id);
152 		return 0;
153 	}
154 
155 	for (i = 0; i < buf_num; i++) {
156 		err = mvneta_bm_pool_refill(priv, bm_pool);
157 		if (err < 0)
158 			break;
159 	}
160 
161 	/* Update BM driver with number of buffers added to pool */
162 	bm_pool->buf_num += i;
163 
164 	dev_dbg(&priv->pdev->dev,
165 		"%s pool %d: pkt_size=%4d, buf_size=%4d, frag_size=%4d\n",
166 		bm_pool->type == MVNETA_BM_SHORT ? "short" : "long",
167 		bm_pool->id, bm_pool->pkt_size, bm_pool->buf_size,
168 		bm_pool->frag_size);
169 
170 	dev_dbg(&priv->pdev->dev,
171 		"%s pool %d: %d of %d buffers added\n",
172 		bm_pool->type == MVNETA_BM_SHORT ? "short" : "long",
173 		bm_pool->id, i, buf_num);
174 
175 	return i;
176 }
177 EXPORT_SYMBOL_GPL(mvneta_bm_bufs_add);
178 
179 /* Create pool */
180 static int mvneta_bm_pool_create(struct mvneta_bm *priv,
181 				 struct mvneta_bm_pool *bm_pool)
182 {
183 	struct platform_device *pdev = priv->pdev;
184 	u8 target_id, attr;
185 	int size_bytes, err;
186 
187 	size_bytes = sizeof(u32) * bm_pool->size;
188 	bm_pool->virt_addr = dma_alloc_coherent(&pdev->dev, size_bytes,
189 						&bm_pool->phys_addr,
190 						GFP_KERNEL);
191 	if (!bm_pool->virt_addr)
192 		return -ENOMEM;
193 
194 	if (!IS_ALIGNED((u32)bm_pool->virt_addr, MVNETA_BM_POOL_PTR_ALIGN)) {
195 		dma_free_coherent(&pdev->dev, size_bytes, bm_pool->virt_addr,
196 				  bm_pool->phys_addr);
197 		dev_err(&pdev->dev, "BM pool %d is not %d bytes aligned\n",
198 			bm_pool->id, MVNETA_BM_POOL_PTR_ALIGN);
199 		return -ENOMEM;
200 	}
201 
202 	err = mvebu_mbus_get_dram_win_info(bm_pool->phys_addr, &target_id,
203 					   &attr);
204 	if (err < 0) {
205 		dma_free_coherent(&pdev->dev, size_bytes, bm_pool->virt_addr,
206 				  bm_pool->phys_addr);
207 		return err;
208 	}
209 
210 	/* Set pool address */
211 	mvneta_bm_write(priv, MVNETA_BM_POOL_BASE_REG(bm_pool->id),
212 			bm_pool->phys_addr);
213 
214 	mvneta_bm_pool_target_set(priv, bm_pool->id, target_id,  attr);
215 	mvneta_bm_pool_enable(priv, bm_pool->id);
216 
217 	return 0;
218 }
219 
220 /* Notify the driver that BM pool is being used as specific type and return the
221  * pool pointer on success
222  */
223 struct mvneta_bm_pool *mvneta_bm_pool_use(struct mvneta_bm *priv, u8 pool_id,
224 					  enum mvneta_bm_type type, u8 port_id,
225 					  int pkt_size)
226 {
227 	struct mvneta_bm_pool *new_pool = &priv->bm_pools[pool_id];
228 	int num, err;
229 
230 	if (new_pool->type == MVNETA_BM_LONG &&
231 	    new_pool->port_map != 1 << port_id) {
232 		dev_err(&priv->pdev->dev,
233 			"long pool cannot be shared by the ports\n");
234 		return NULL;
235 	}
236 
237 	if (new_pool->type == MVNETA_BM_SHORT && new_pool->type != type) {
238 		dev_err(&priv->pdev->dev,
239 			"mixing pools' types between the ports is forbidden\n");
240 		return NULL;
241 	}
242 
243 	if (new_pool->pkt_size == 0 || type != MVNETA_BM_SHORT)
244 		new_pool->pkt_size = pkt_size;
245 
246 	/* Allocate buffers in case BM pool hasn't been used yet */
247 	if (new_pool->type == MVNETA_BM_FREE) {
248 		new_pool->type = type;
249 		new_pool->buf_size = MVNETA_RX_BUF_SIZE(new_pool->pkt_size);
250 		new_pool->frag_size =
251 			SKB_DATA_ALIGN(MVNETA_RX_BUF_SIZE(new_pool->pkt_size)) +
252 			SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
253 
254 		/* Create new pool */
255 		err = mvneta_bm_pool_create(priv, new_pool);
256 		if (err) {
257 			dev_err(&priv->pdev->dev, "fail to create pool %d\n",
258 				new_pool->id);
259 			return NULL;
260 		}
261 
262 		/* Allocate buffers for this pool */
263 		num = mvneta_bm_bufs_add(priv, new_pool, new_pool->size);
264 		if (num != new_pool->size) {
265 			WARN(1, "pool %d: %d of %d allocated\n",
266 			     new_pool->id, num, new_pool->size);
267 			return NULL;
268 		}
269 	}
270 
271 	return new_pool;
272 }
273 EXPORT_SYMBOL_GPL(mvneta_bm_pool_use);
274 
275 /* Free all buffers from the pool */
276 void mvneta_bm_bufs_free(struct mvneta_bm *priv, struct mvneta_bm_pool *bm_pool,
277 			 u8 port_map)
278 {
279 	int i;
280 
281 	bm_pool->port_map &= ~port_map;
282 	if (bm_pool->port_map)
283 		return;
284 
285 	mvneta_bm_config_set(priv, MVNETA_BM_EMPTY_LIMIT_MASK);
286 
287 	for (i = 0; i < bm_pool->buf_num; i++) {
288 		dma_addr_t buf_phys_addr;
289 		u32 *vaddr;
290 
291 		/* Get buffer physical address (indirect access) */
292 		buf_phys_addr = mvneta_bm_pool_get_bp(priv, bm_pool);
293 
294 		/* Work-around to the problems when destroying the pool,
295 		 * when it occurs that a read access to BPPI returns 0.
296 		 */
297 		if (buf_phys_addr == 0)
298 			continue;
299 
300 		vaddr = phys_to_virt(buf_phys_addr);
301 		if (!vaddr)
302 			break;
303 
304 		dma_unmap_single(&priv->pdev->dev, buf_phys_addr,
305 				 bm_pool->buf_size, DMA_FROM_DEVICE);
306 		mvneta_frag_free(bm_pool->frag_size, vaddr);
307 	}
308 
309 	mvneta_bm_config_clear(priv, MVNETA_BM_EMPTY_LIMIT_MASK);
310 
311 	/* Update BM driver with number of buffers removed from pool */
312 	bm_pool->buf_num -= i;
313 }
314 EXPORT_SYMBOL_GPL(mvneta_bm_bufs_free);
315 
316 /* Cleanup pool */
317 void mvneta_bm_pool_destroy(struct mvneta_bm *priv,
318 			    struct mvneta_bm_pool *bm_pool, u8 port_map)
319 {
320 	bm_pool->port_map &= ~port_map;
321 	if (bm_pool->port_map)
322 		return;
323 
324 	bm_pool->type = MVNETA_BM_FREE;
325 
326 	mvneta_bm_bufs_free(priv, bm_pool, port_map);
327 	if (bm_pool->buf_num)
328 		WARN(1, "cannot free all buffers in pool %d\n", bm_pool->id);
329 
330 	if (bm_pool->virt_addr) {
331 		dma_free_coherent(&priv->pdev->dev, sizeof(u32) * bm_pool->size,
332 				  bm_pool->virt_addr, bm_pool->phys_addr);
333 		bm_pool->virt_addr = NULL;
334 	}
335 
336 	mvneta_bm_pool_disable(priv, bm_pool->id);
337 }
338 EXPORT_SYMBOL_GPL(mvneta_bm_pool_destroy);
339 
340 static void mvneta_bm_pools_init(struct mvneta_bm *priv)
341 {
342 	struct device_node *dn = priv->pdev->dev.of_node;
343 	struct mvneta_bm_pool *bm_pool;
344 	char prop[15];
345 	u32 size;
346 	int i;
347 
348 	/* Activate BM unit */
349 	mvneta_bm_write(priv, MVNETA_BM_COMMAND_REG, MVNETA_BM_START_MASK);
350 
351 	/* Create all pools with maximum size */
352 	for (i = 0; i < MVNETA_BM_POOLS_NUM; i++) {
353 		bm_pool = &priv->bm_pools[i];
354 		bm_pool->id = i;
355 		bm_pool->type = MVNETA_BM_FREE;
356 
357 		/* Reset read pointer */
358 		mvneta_bm_write(priv, MVNETA_BM_POOL_READ_PTR_REG(i), 0);
359 
360 		/* Reset write pointer */
361 		mvneta_bm_write(priv, MVNETA_BM_POOL_WRITE_PTR_REG(i), 0);
362 
363 		/* Configure pool size according to DT or use default value */
364 		sprintf(prop, "pool%d,capacity", i);
365 		if (of_property_read_u32(dn, prop, &size)) {
366 			size = MVNETA_BM_POOL_CAP_DEF;
367 		} else if (size > MVNETA_BM_POOL_CAP_MAX) {
368 			dev_warn(&priv->pdev->dev,
369 				 "Illegal pool %d capacity %d, set to %d\n",
370 				 i, size, MVNETA_BM_POOL_CAP_MAX);
371 			size = MVNETA_BM_POOL_CAP_MAX;
372 		} else if (size < MVNETA_BM_POOL_CAP_MIN) {
373 			dev_warn(&priv->pdev->dev,
374 				 "Illegal pool %d capacity %d, set to %d\n",
375 				 i, size, MVNETA_BM_POOL_CAP_MIN);
376 			size = MVNETA_BM_POOL_CAP_MIN;
377 		} else if (!IS_ALIGNED(size, MVNETA_BM_POOL_CAP_ALIGN)) {
378 			dev_warn(&priv->pdev->dev,
379 				 "Illegal pool %d capacity %d, round to %d\n",
380 				 i, size, ALIGN(size,
381 				 MVNETA_BM_POOL_CAP_ALIGN));
382 			size = ALIGN(size, MVNETA_BM_POOL_CAP_ALIGN);
383 		}
384 		bm_pool->size = size;
385 
386 		mvneta_bm_write(priv, MVNETA_BM_POOL_SIZE_REG(i),
387 				bm_pool->size);
388 
389 		/* Obtain custom pkt_size from DT */
390 		sprintf(prop, "pool%d,pkt-size", i);
391 		if (of_property_read_u32(dn, prop, &bm_pool->pkt_size))
392 			bm_pool->pkt_size = 0;
393 	}
394 }
395 
396 static void mvneta_bm_default_set(struct mvneta_bm *priv)
397 {
398 	u32 val;
399 
400 	/* Mask BM all interrupts */
401 	mvneta_bm_write(priv, MVNETA_BM_INTR_MASK_REG, 0);
402 
403 	/* Clear BM cause register */
404 	mvneta_bm_write(priv, MVNETA_BM_INTR_CAUSE_REG, 0);
405 
406 	/* Set BM configuration register */
407 	val = mvneta_bm_read(priv, MVNETA_BM_CONFIG_REG);
408 
409 	/* Reduce MaxInBurstSize from 32 BPs to 16 BPs */
410 	val &= ~MVNETA_BM_MAX_IN_BURST_SIZE_MASK;
411 	val |= MVNETA_BM_MAX_IN_BURST_SIZE_16BP;
412 	mvneta_bm_write(priv, MVNETA_BM_CONFIG_REG, val);
413 }
414 
415 static int mvneta_bm_init(struct mvneta_bm *priv)
416 {
417 	mvneta_bm_default_set(priv);
418 
419 	/* Allocate and initialize BM pools structures */
420 	priv->bm_pools = devm_kcalloc(&priv->pdev->dev, MVNETA_BM_POOLS_NUM,
421 				      sizeof(struct mvneta_bm_pool),
422 				      GFP_KERNEL);
423 	if (!priv->bm_pools)
424 		return -ENOMEM;
425 
426 	mvneta_bm_pools_init(priv);
427 
428 	return 0;
429 }
430 
431 static int mvneta_bm_get_sram(struct device_node *dn,
432 			      struct mvneta_bm *priv)
433 {
434 	priv->bppi_pool = of_gen_pool_get(dn, "internal-mem", 0);
435 	if (!priv->bppi_pool)
436 		return -ENOMEM;
437 
438 	priv->bppi_virt_addr = gen_pool_dma_alloc(priv->bppi_pool,
439 						  MVNETA_BM_BPPI_SIZE,
440 						  &priv->bppi_phys_addr);
441 	if (!priv->bppi_virt_addr)
442 		return -ENOMEM;
443 
444 	return 0;
445 }
446 
447 static void mvneta_bm_put_sram(struct mvneta_bm *priv)
448 {
449 	gen_pool_free(priv->bppi_pool, priv->bppi_phys_addr,
450 		      MVNETA_BM_BPPI_SIZE);
451 }
452 
453 static int mvneta_bm_probe(struct platform_device *pdev)
454 {
455 	struct device_node *dn = pdev->dev.of_node;
456 	struct mvneta_bm *priv;
457 	struct resource *res;
458 	int err;
459 
460 	priv = devm_kzalloc(&pdev->dev, sizeof(struct mvneta_bm), GFP_KERNEL);
461 	if (!priv)
462 		return -ENOMEM;
463 
464 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
465 	priv->reg_base = devm_ioremap_resource(&pdev->dev, res);
466 	if (IS_ERR(priv->reg_base))
467 		return PTR_ERR(priv->reg_base);
468 
469 	priv->clk = devm_clk_get(&pdev->dev, NULL);
470 	if (IS_ERR(priv->clk))
471 		return PTR_ERR(priv->clk);
472 	err = clk_prepare_enable(priv->clk);
473 	if (err < 0)
474 		return err;
475 
476 	err = mvneta_bm_get_sram(dn, priv);
477 	if (err < 0) {
478 		dev_err(&pdev->dev, "failed to allocate internal memory\n");
479 		goto err_clk;
480 	}
481 
482 	priv->pdev = pdev;
483 
484 	/* Initialize buffer manager internals */
485 	err = mvneta_bm_init(priv);
486 	if (err < 0) {
487 		dev_err(&pdev->dev, "failed to initialize controller\n");
488 		goto err_sram;
489 	}
490 
491 	dn->data = priv;
492 	platform_set_drvdata(pdev, priv);
493 
494 	dev_info(&pdev->dev, "Buffer Manager for network controller enabled\n");
495 
496 	return 0;
497 
498 err_sram:
499 	mvneta_bm_put_sram(priv);
500 err_clk:
501 	clk_disable_unprepare(priv->clk);
502 	return err;
503 }
504 
505 static int mvneta_bm_remove(struct platform_device *pdev)
506 {
507 	struct mvneta_bm *priv = platform_get_drvdata(pdev);
508 	u8 all_ports_map = 0xff;
509 	int i = 0;
510 
511 	for (i = 0; i < MVNETA_BM_POOLS_NUM; i++) {
512 		struct mvneta_bm_pool *bm_pool = &priv->bm_pools[i];
513 
514 		mvneta_bm_pool_destroy(priv, bm_pool, all_ports_map);
515 	}
516 
517 	mvneta_bm_put_sram(priv);
518 
519 	/* Dectivate BM unit */
520 	mvneta_bm_write(priv, MVNETA_BM_COMMAND_REG, MVNETA_BM_STOP_MASK);
521 
522 	clk_disable_unprepare(priv->clk);
523 
524 	return 0;
525 }
526 
527 static const struct of_device_id mvneta_bm_match[] = {
528 	{ .compatible = "marvell,armada-380-neta-bm" },
529 	{ }
530 };
531 MODULE_DEVICE_TABLE(of, mvneta_bm_match);
532 
533 static struct platform_driver mvneta_bm_driver = {
534 	.probe = mvneta_bm_probe,
535 	.remove = mvneta_bm_remove,
536 	.driver = {
537 		.name = MVNETA_BM_DRIVER_NAME,
538 		.of_match_table = mvneta_bm_match,
539 	},
540 };
541 
542 module_platform_driver(mvneta_bm_driver);
543 
544 MODULE_DESCRIPTION("Marvell NETA Buffer Manager Driver - www.marvell.com");
545 MODULE_AUTHOR("Marcin Wojtas <mw@semihalf.com>");
546 MODULE_LICENSE("GPL v2");
547