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