xref: /linux/drivers/net/ethernet/marvell/mvneta_bm.c (revision c78a85a8430e35aecd53e190a2f6b999062b1037)
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/clk.h>
14 #include <linux/genalloc.h>
15 #include <linux/io.h>
16 #include <linux/kernel.h>
17 #include <linux/mbus.h>
18 #include <linux/module.h>
19 #include <linux/netdevice.h>
20 #include <linux/of.h>
21 #include <linux/platform_device.h>
22 #include <linux/skbuff.h>
23 #include <net/hwbm.h>
24 #include "mvneta_bm.h"
25 
26 #define MVNETA_BM_DRIVER_NAME "mvneta_bm"
27 #define MVNETA_BM_DRIVER_VERSION "1.0"
28 
29 static void mvneta_bm_write(struct mvneta_bm *priv, u32 offset, u32 data)
30 {
31 	writel(data, priv->reg_base + offset);
32 }
33 
34 static u32 mvneta_bm_read(struct mvneta_bm *priv, u32 offset)
35 {
36 	return readl(priv->reg_base + offset);
37 }
38 
39 static void mvneta_bm_pool_enable(struct mvneta_bm *priv, int pool_id)
40 {
41 	u32 val;
42 
43 	val = mvneta_bm_read(priv, MVNETA_BM_POOL_BASE_REG(pool_id));
44 	val |= MVNETA_BM_POOL_ENABLE_MASK;
45 	mvneta_bm_write(priv, MVNETA_BM_POOL_BASE_REG(pool_id), val);
46 
47 	/* Clear BM cause register */
48 	mvneta_bm_write(priv, MVNETA_BM_INTR_CAUSE_REG, 0);
49 }
50 
51 static void mvneta_bm_pool_disable(struct mvneta_bm *priv, int pool_id)
52 {
53 	u32 val;
54 
55 	val = mvneta_bm_read(priv, MVNETA_BM_POOL_BASE_REG(pool_id));
56 	val &= ~MVNETA_BM_POOL_ENABLE_MASK;
57 	mvneta_bm_write(priv, MVNETA_BM_POOL_BASE_REG(pool_id), val);
58 }
59 
60 static inline void mvneta_bm_config_set(struct mvneta_bm *priv, u32 mask)
61 {
62 	u32 val;
63 
64 	val = mvneta_bm_read(priv, MVNETA_BM_CONFIG_REG);
65 	val |= mask;
66 	mvneta_bm_write(priv, MVNETA_BM_CONFIG_REG, val);
67 }
68 
69 static inline void mvneta_bm_config_clear(struct mvneta_bm *priv, u32 mask)
70 {
71 	u32 val;
72 
73 	val = mvneta_bm_read(priv, MVNETA_BM_CONFIG_REG);
74 	val &= ~mask;
75 	mvneta_bm_write(priv, MVNETA_BM_CONFIG_REG, val);
76 }
77 
78 static void mvneta_bm_pool_target_set(struct mvneta_bm *priv, int pool_id,
79 				      u8 target_id, u8 attr)
80 {
81 	u32 val;
82 
83 	val = mvneta_bm_read(priv, MVNETA_BM_XBAR_POOL_REG(pool_id));
84 	val &= ~MVNETA_BM_TARGET_ID_MASK(pool_id);
85 	val &= ~MVNETA_BM_XBAR_ATTR_MASK(pool_id);
86 	val |= MVNETA_BM_TARGET_ID_VAL(pool_id, target_id);
87 	val |= MVNETA_BM_XBAR_ATTR_VAL(pool_id, attr);
88 
89 	mvneta_bm_write(priv, MVNETA_BM_XBAR_POOL_REG(pool_id), val);
90 }
91 
92 int mvneta_bm_construct(struct hwbm_pool *hwbm_pool, void *buf)
93 {
94 	struct mvneta_bm_pool *bm_pool =
95 		(struct mvneta_bm_pool *)hwbm_pool->priv;
96 	struct mvneta_bm *priv = bm_pool->priv;
97 	dma_addr_t phys_addr;
98 
99 	/* In order to update buf_cookie field of RX descriptor properly,
100 	 * BM hardware expects buf virtual address to be placed in the
101 	 * first four bytes of mapped buffer.
102 	 */
103 	*(u32 *)buf = (u32)buf;
104 	phys_addr = dma_map_single(&priv->pdev->dev, buf, bm_pool->buf_size,
105 				   DMA_FROM_DEVICE);
106 	if (unlikely(dma_mapping_error(&priv->pdev->dev, phys_addr)))
107 		return -ENOMEM;
108 
109 	mvneta_bm_pool_put_bp(priv, bm_pool, phys_addr);
110 	return 0;
111 }
112 EXPORT_SYMBOL_GPL(mvneta_bm_construct);
113 
114 /* Create pool */
115 static int mvneta_bm_pool_create(struct mvneta_bm *priv,
116 				 struct mvneta_bm_pool *bm_pool)
117 {
118 	struct platform_device *pdev = priv->pdev;
119 	u8 target_id, attr;
120 	int size_bytes, err;
121 	size_bytes = sizeof(u32) * bm_pool->hwbm_pool.size;
122 	bm_pool->virt_addr = dma_alloc_coherent(&pdev->dev, size_bytes,
123 						&bm_pool->phys_addr,
124 						GFP_KERNEL);
125 	if (!bm_pool->virt_addr)
126 		return -ENOMEM;
127 
128 	if (!IS_ALIGNED((u32)bm_pool->virt_addr, MVNETA_BM_POOL_PTR_ALIGN)) {
129 		dma_free_coherent(&pdev->dev, size_bytes, bm_pool->virt_addr,
130 				  bm_pool->phys_addr);
131 		dev_err(&pdev->dev, "BM pool %d is not %d bytes aligned\n",
132 			bm_pool->id, MVNETA_BM_POOL_PTR_ALIGN);
133 		return -ENOMEM;
134 	}
135 
136 	err = mvebu_mbus_get_dram_win_info(bm_pool->phys_addr, &target_id,
137 					   &attr);
138 	if (err < 0) {
139 		dma_free_coherent(&pdev->dev, size_bytes, bm_pool->virt_addr,
140 				  bm_pool->phys_addr);
141 		return err;
142 	}
143 
144 	/* Set pool address */
145 	mvneta_bm_write(priv, MVNETA_BM_POOL_BASE_REG(bm_pool->id),
146 			bm_pool->phys_addr);
147 
148 	mvneta_bm_pool_target_set(priv, bm_pool->id, target_id,  attr);
149 	mvneta_bm_pool_enable(priv, bm_pool->id);
150 
151 	return 0;
152 }
153 
154 /* Notify the driver that BM pool is being used as specific type and return the
155  * pool pointer on success
156  */
157 struct mvneta_bm_pool *mvneta_bm_pool_use(struct mvneta_bm *priv, u8 pool_id,
158 					  enum mvneta_bm_type type, u8 port_id,
159 					  int pkt_size)
160 {
161 	struct mvneta_bm_pool *new_pool = &priv->bm_pools[pool_id];
162 	int num, err;
163 
164 	if (new_pool->type == MVNETA_BM_LONG &&
165 	    new_pool->port_map != 1 << port_id) {
166 		dev_err(&priv->pdev->dev,
167 			"long pool cannot be shared by the ports\n");
168 		return NULL;
169 	}
170 
171 	if (new_pool->type == MVNETA_BM_SHORT && new_pool->type != type) {
172 		dev_err(&priv->pdev->dev,
173 			"mixing pools' types between the ports is forbidden\n");
174 		return NULL;
175 	}
176 
177 	if (new_pool->pkt_size == 0 || type != MVNETA_BM_SHORT)
178 		new_pool->pkt_size = pkt_size;
179 
180 	/* Allocate buffers in case BM pool hasn't been used yet */
181 	if (new_pool->type == MVNETA_BM_FREE) {
182 		struct hwbm_pool *hwbm_pool = &new_pool->hwbm_pool;
183 
184 		new_pool->priv = priv;
185 		new_pool->type = type;
186 		new_pool->buf_size = MVNETA_RX_BUF_SIZE(new_pool->pkt_size);
187 		hwbm_pool->frag_size =
188 			SKB_DATA_ALIGN(MVNETA_RX_BUF_SIZE(new_pool->pkt_size)) +
189 			SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
190 		hwbm_pool->construct = mvneta_bm_construct;
191 		hwbm_pool->priv = new_pool;
192 
193 		/* Create new pool */
194 		err = mvneta_bm_pool_create(priv, new_pool);
195 		if (err) {
196 			dev_err(&priv->pdev->dev, "fail to create pool %d\n",
197 				new_pool->id);
198 			return NULL;
199 		}
200 
201 		/* Allocate buffers for this pool */
202 		num = hwbm_pool_add(hwbm_pool, hwbm_pool->size, GFP_ATOMIC);
203 		if (num != hwbm_pool->size) {
204 			WARN(1, "pool %d: %d of %d allocated\n",
205 			     new_pool->id, num, hwbm_pool->size);
206 			return NULL;
207 		}
208 	}
209 
210 	return new_pool;
211 }
212 EXPORT_SYMBOL_GPL(mvneta_bm_pool_use);
213 
214 /* Free all buffers from the pool */
215 void mvneta_bm_bufs_free(struct mvneta_bm *priv, struct mvneta_bm_pool *bm_pool,
216 			 u8 port_map)
217 {
218 	int i;
219 
220 	bm_pool->port_map &= ~port_map;
221 	if (bm_pool->port_map)
222 		return;
223 
224 	mvneta_bm_config_set(priv, MVNETA_BM_EMPTY_LIMIT_MASK);
225 
226 	for (i = 0; i < bm_pool->hwbm_pool.buf_num; i++) {
227 		dma_addr_t buf_phys_addr;
228 		u32 *vaddr;
229 
230 		/* Get buffer physical address (indirect access) */
231 		buf_phys_addr = mvneta_bm_pool_get_bp(priv, bm_pool);
232 
233 		/* Work-around to the problems when destroying the pool,
234 		 * when it occurs that a read access to BPPI returns 0.
235 		 */
236 		if (buf_phys_addr == 0)
237 			continue;
238 
239 		vaddr = phys_to_virt(buf_phys_addr);
240 		if (!vaddr)
241 			break;
242 
243 		dma_unmap_single(&priv->pdev->dev, buf_phys_addr,
244 				 bm_pool->buf_size, DMA_FROM_DEVICE);
245 		hwbm_buf_free(&bm_pool->hwbm_pool, vaddr);
246 	}
247 
248 	mvneta_bm_config_clear(priv, MVNETA_BM_EMPTY_LIMIT_MASK);
249 
250 	/* Update BM driver with number of buffers removed from pool */
251 	bm_pool->hwbm_pool.buf_num -= i;
252 }
253 EXPORT_SYMBOL_GPL(mvneta_bm_bufs_free);
254 
255 /* Cleanup pool */
256 void mvneta_bm_pool_destroy(struct mvneta_bm *priv,
257 			    struct mvneta_bm_pool *bm_pool, u8 port_map)
258 {
259 	struct hwbm_pool *hwbm_pool = &bm_pool->hwbm_pool;
260 	bm_pool->port_map &= ~port_map;
261 	if (bm_pool->port_map)
262 		return;
263 
264 	bm_pool->type = MVNETA_BM_FREE;
265 
266 	mvneta_bm_bufs_free(priv, bm_pool, port_map);
267 	if (hwbm_pool->buf_num)
268 		WARN(1, "cannot free all buffers in pool %d\n", bm_pool->id);
269 
270 	if (bm_pool->virt_addr) {
271 		dma_free_coherent(&priv->pdev->dev,
272 				  sizeof(u32) * hwbm_pool->size,
273 				  bm_pool->virt_addr, bm_pool->phys_addr);
274 		bm_pool->virt_addr = NULL;
275 	}
276 
277 	mvneta_bm_pool_disable(priv, bm_pool->id);
278 }
279 EXPORT_SYMBOL_GPL(mvneta_bm_pool_destroy);
280 
281 static void mvneta_bm_pools_init(struct mvneta_bm *priv)
282 {
283 	struct device_node *dn = priv->pdev->dev.of_node;
284 	struct mvneta_bm_pool *bm_pool;
285 	char prop[15];
286 	u32 size;
287 	int i;
288 
289 	/* Activate BM unit */
290 	mvneta_bm_write(priv, MVNETA_BM_COMMAND_REG, MVNETA_BM_START_MASK);
291 
292 	/* Create all pools with maximum size */
293 	for (i = 0; i < MVNETA_BM_POOLS_NUM; i++) {
294 		bm_pool = &priv->bm_pools[i];
295 		bm_pool->id = i;
296 		bm_pool->type = MVNETA_BM_FREE;
297 
298 		/* Reset read pointer */
299 		mvneta_bm_write(priv, MVNETA_BM_POOL_READ_PTR_REG(i), 0);
300 
301 		/* Reset write pointer */
302 		mvneta_bm_write(priv, MVNETA_BM_POOL_WRITE_PTR_REG(i), 0);
303 
304 		/* Configure pool size according to DT or use default value */
305 		sprintf(prop, "pool%d,capacity", i);
306 		if (of_property_read_u32(dn, prop, &size)) {
307 			size = MVNETA_BM_POOL_CAP_DEF;
308 		} else if (size > MVNETA_BM_POOL_CAP_MAX) {
309 			dev_warn(&priv->pdev->dev,
310 				 "Illegal pool %d capacity %d, set to %d\n",
311 				 i, size, MVNETA_BM_POOL_CAP_MAX);
312 			size = MVNETA_BM_POOL_CAP_MAX;
313 		} else if (size < MVNETA_BM_POOL_CAP_MIN) {
314 			dev_warn(&priv->pdev->dev,
315 				 "Illegal pool %d capacity %d, set to %d\n",
316 				 i, size, MVNETA_BM_POOL_CAP_MIN);
317 			size = MVNETA_BM_POOL_CAP_MIN;
318 		} else if (!IS_ALIGNED(size, MVNETA_BM_POOL_CAP_ALIGN)) {
319 			dev_warn(&priv->pdev->dev,
320 				 "Illegal pool %d capacity %d, round to %d\n",
321 				 i, size, ALIGN(size,
322 				 MVNETA_BM_POOL_CAP_ALIGN));
323 			size = ALIGN(size, MVNETA_BM_POOL_CAP_ALIGN);
324 		}
325 		bm_pool->hwbm_pool.size = size;
326 
327 		mvneta_bm_write(priv, MVNETA_BM_POOL_SIZE_REG(i),
328 				bm_pool->hwbm_pool.size);
329 
330 		/* Obtain custom pkt_size from DT */
331 		sprintf(prop, "pool%d,pkt-size", i);
332 		if (of_property_read_u32(dn, prop, &bm_pool->pkt_size))
333 			bm_pool->pkt_size = 0;
334 	}
335 }
336 
337 static void mvneta_bm_default_set(struct mvneta_bm *priv)
338 {
339 	u32 val;
340 
341 	/* Mask BM all interrupts */
342 	mvneta_bm_write(priv, MVNETA_BM_INTR_MASK_REG, 0);
343 
344 	/* Clear BM cause register */
345 	mvneta_bm_write(priv, MVNETA_BM_INTR_CAUSE_REG, 0);
346 
347 	/* Set BM configuration register */
348 	val = mvneta_bm_read(priv, MVNETA_BM_CONFIG_REG);
349 
350 	/* Reduce MaxInBurstSize from 32 BPs to 16 BPs */
351 	val &= ~MVNETA_BM_MAX_IN_BURST_SIZE_MASK;
352 	val |= MVNETA_BM_MAX_IN_BURST_SIZE_16BP;
353 	mvneta_bm_write(priv, MVNETA_BM_CONFIG_REG, val);
354 }
355 
356 static int mvneta_bm_init(struct mvneta_bm *priv)
357 {
358 	mvneta_bm_default_set(priv);
359 
360 	/* Allocate and initialize BM pools structures */
361 	priv->bm_pools = devm_kcalloc(&priv->pdev->dev, MVNETA_BM_POOLS_NUM,
362 				      sizeof(struct mvneta_bm_pool),
363 				      GFP_KERNEL);
364 	if (!priv->bm_pools)
365 		return -ENOMEM;
366 
367 	mvneta_bm_pools_init(priv);
368 
369 	return 0;
370 }
371 
372 static int mvneta_bm_get_sram(struct device_node *dn,
373 			      struct mvneta_bm *priv)
374 {
375 	priv->bppi_pool = of_gen_pool_get(dn, "internal-mem", 0);
376 	if (!priv->bppi_pool)
377 		return -ENOMEM;
378 
379 	priv->bppi_virt_addr = gen_pool_dma_alloc(priv->bppi_pool,
380 						  MVNETA_BM_BPPI_SIZE,
381 						  &priv->bppi_phys_addr);
382 	if (!priv->bppi_virt_addr)
383 		return -ENOMEM;
384 
385 	return 0;
386 }
387 
388 static void mvneta_bm_put_sram(struct mvneta_bm *priv)
389 {
390 	gen_pool_free(priv->bppi_pool, priv->bppi_phys_addr,
391 		      MVNETA_BM_BPPI_SIZE);
392 }
393 
394 static int mvneta_bm_probe(struct platform_device *pdev)
395 {
396 	struct device_node *dn = pdev->dev.of_node;
397 	struct mvneta_bm *priv;
398 	struct resource *res;
399 	int err;
400 
401 	priv = devm_kzalloc(&pdev->dev, sizeof(struct mvneta_bm), GFP_KERNEL);
402 	if (!priv)
403 		return -ENOMEM;
404 
405 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
406 	priv->reg_base = devm_ioremap_resource(&pdev->dev, res);
407 	if (IS_ERR(priv->reg_base))
408 		return PTR_ERR(priv->reg_base);
409 
410 	priv->clk = devm_clk_get(&pdev->dev, NULL);
411 	if (IS_ERR(priv->clk))
412 		return PTR_ERR(priv->clk);
413 	err = clk_prepare_enable(priv->clk);
414 	if (err < 0)
415 		return err;
416 
417 	err = mvneta_bm_get_sram(dn, priv);
418 	if (err < 0) {
419 		dev_err(&pdev->dev, "failed to allocate internal memory\n");
420 		goto err_clk;
421 	}
422 
423 	priv->pdev = pdev;
424 
425 	/* Initialize buffer manager internals */
426 	err = mvneta_bm_init(priv);
427 	if (err < 0) {
428 		dev_err(&pdev->dev, "failed to initialize controller\n");
429 		goto err_sram;
430 	}
431 
432 	dn->data = priv;
433 	platform_set_drvdata(pdev, priv);
434 
435 	dev_info(&pdev->dev, "Buffer Manager for network controller enabled\n");
436 
437 	return 0;
438 
439 err_sram:
440 	mvneta_bm_put_sram(priv);
441 err_clk:
442 	clk_disable_unprepare(priv->clk);
443 	return err;
444 }
445 
446 static int mvneta_bm_remove(struct platform_device *pdev)
447 {
448 	struct mvneta_bm *priv = platform_get_drvdata(pdev);
449 	u8 all_ports_map = 0xff;
450 	int i = 0;
451 
452 	for (i = 0; i < MVNETA_BM_POOLS_NUM; i++) {
453 		struct mvneta_bm_pool *bm_pool = &priv->bm_pools[i];
454 
455 		mvneta_bm_pool_destroy(priv, bm_pool, all_ports_map);
456 	}
457 
458 	mvneta_bm_put_sram(priv);
459 
460 	/* Dectivate BM unit */
461 	mvneta_bm_write(priv, MVNETA_BM_COMMAND_REG, MVNETA_BM_STOP_MASK);
462 
463 	clk_disable_unprepare(priv->clk);
464 
465 	return 0;
466 }
467 
468 static const struct of_device_id mvneta_bm_match[] = {
469 	{ .compatible = "marvell,armada-380-neta-bm" },
470 	{ }
471 };
472 MODULE_DEVICE_TABLE(of, mvneta_bm_match);
473 
474 static struct platform_driver mvneta_bm_driver = {
475 	.probe = mvneta_bm_probe,
476 	.remove = mvneta_bm_remove,
477 	.driver = {
478 		.name = MVNETA_BM_DRIVER_NAME,
479 		.of_match_table = mvneta_bm_match,
480 	},
481 };
482 
483 module_platform_driver(mvneta_bm_driver);
484 
485 MODULE_DESCRIPTION("Marvell NETA Buffer Manager Driver - www.marvell.com");
486 MODULE_AUTHOR("Marcin Wojtas <mw@semihalf.com>");
487 MODULE_LICENSE("GPL v2");
488