1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2015-2016 Marvell International Ltd.
4
5 */
6
7#include <linux/clk.h>
8#include <linux/dma-mapping.h>
9#include <linux/interrupt.h>
10#include <linux/io.h>
11#include <linux/module.h>
12#include <linux/msi.h>
13#include <linux/of.h>
14#include <linux/of_irq.h>
15#include <linux/platform_device.h>
16#include <linux/spinlock.h>
17
18#include "dmaengine.h"
19
20/* DMA Engine Registers */
21#define MV_XOR_V2_DMA_DESQ_BALR_OFF			0x000
22#define MV_XOR_V2_DMA_DESQ_BAHR_OFF			0x004
23#define MV_XOR_V2_DMA_DESQ_SIZE_OFF			0x008
24#define MV_XOR_V2_DMA_DESQ_DONE_OFF			0x00C
25#define   MV_XOR_V2_DMA_DESQ_DONE_PENDING_MASK		0x7FFF
26#define   MV_XOR_V2_DMA_DESQ_DONE_PENDING_SHIFT		0
27#define   MV_XOR_V2_DMA_DESQ_DONE_READ_PTR_MASK		0x1FFF
28#define   MV_XOR_V2_DMA_DESQ_DONE_READ_PTR_SHIFT	16
29#define MV_XOR_V2_DMA_DESQ_ARATTR_OFF			0x010
30#define   MV_XOR_V2_DMA_DESQ_ATTR_CACHE_MASK		0x3F3F
31#define   MV_XOR_V2_DMA_DESQ_ATTR_OUTER_SHAREABLE	0x202
32#define   MV_XOR_V2_DMA_DESQ_ATTR_CACHEABLE		0x3C3C
33#define MV_XOR_V2_DMA_IMSG_CDAT_OFF			0x014
34#define MV_XOR_V2_DMA_IMSG_THRD_OFF			0x018
35#define   MV_XOR_V2_DMA_IMSG_THRD_MASK			0x7FFF
36#define   MV_XOR_V2_DMA_IMSG_TIMER_EN			BIT(18)
37#define MV_XOR_V2_DMA_DESQ_AWATTR_OFF			0x01C
38  /* Same flags as MV_XOR_V2_DMA_DESQ_ARATTR_OFF */
39#define MV_XOR_V2_DMA_DESQ_ALLOC_OFF			0x04C
40#define   MV_XOR_V2_DMA_DESQ_ALLOC_WRPTR_MASK		0xFFFF
41#define   MV_XOR_V2_DMA_DESQ_ALLOC_WRPTR_SHIFT		16
42#define MV_XOR_V2_DMA_IMSG_BALR_OFF			0x050
43#define MV_XOR_V2_DMA_IMSG_BAHR_OFF			0x054
44#define MV_XOR_V2_DMA_DESQ_CTRL_OFF			0x100
45#define	  MV_XOR_V2_DMA_DESQ_CTRL_32B			1
46#define   MV_XOR_V2_DMA_DESQ_CTRL_128B			7
47#define MV_XOR_V2_DMA_DESQ_STOP_OFF			0x800
48#define MV_XOR_V2_DMA_DESQ_DEALLOC_OFF			0x804
49#define MV_XOR_V2_DMA_DESQ_ADD_OFF			0x808
50#define MV_XOR_V2_DMA_IMSG_TMOT				0x810
51#define   MV_XOR_V2_DMA_IMSG_TIMER_THRD_MASK		0x1FFF
52
53/* XOR Global registers */
54#define MV_XOR_V2_GLOB_BW_CTRL				0x4
55#define   MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_RD_SHIFT	0
56#define   MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_RD_VAL	64
57#define   MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_WR_SHIFT	8
58#define   MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_WR_VAL	8
59#define   MV_XOR_V2_GLOB_BW_CTRL_RD_BURST_LEN_SHIFT	12
60#define   MV_XOR_V2_GLOB_BW_CTRL_RD_BURST_LEN_VAL	4
61#define   MV_XOR_V2_GLOB_BW_CTRL_WR_BURST_LEN_SHIFT	16
62#define	  MV_XOR_V2_GLOB_BW_CTRL_WR_BURST_LEN_VAL	4
63#define MV_XOR_V2_GLOB_PAUSE				0x014
64#define   MV_XOR_V2_GLOB_PAUSE_AXI_TIME_DIS_VAL		0x8
65#define MV_XOR_V2_GLOB_SYS_INT_CAUSE			0x200
66#define MV_XOR_V2_GLOB_SYS_INT_MASK			0x204
67#define MV_XOR_V2_GLOB_MEM_INT_CAUSE			0x220
68#define MV_XOR_V2_GLOB_MEM_INT_MASK			0x224
69
70#define MV_XOR_V2_MIN_DESC_SIZE				32
71#define MV_XOR_V2_EXT_DESC_SIZE				128
72
73#define MV_XOR_V2_DESC_RESERVED_SIZE			12
74#define MV_XOR_V2_DESC_BUFF_D_ADDR_SIZE			12
75
76#define MV_XOR_V2_CMD_LINE_NUM_MAX_D_BUF		8
77
78/*
79 * Descriptors queue size. With 32 bytes descriptors, up to 2^14
80 * descriptors are allowed, with 128 bytes descriptors, up to 2^12
81 * descriptors are allowed. This driver uses 128 bytes descriptors,
82 * but experimentation has shown that a set of 1024 descriptors is
83 * sufficient to reach a good level of performance.
84 */
85#define MV_XOR_V2_DESC_NUM				1024
86
87/*
88 * Threshold values for descriptors and timeout, determined by
89 * experimentation as giving a good level of performance.
90 */
91#define MV_XOR_V2_DONE_IMSG_THRD  0x14
92#define MV_XOR_V2_TIMER_THRD      0xB0
93
94/**
95 * struct mv_xor_v2_descriptor - DMA HW descriptor
96 * @desc_id: used by S/W and is not affected by H/W.
97 * @flags: error and status flags
98 * @crc32_result: CRC32 calculation result
99 * @desc_ctrl: operation mode and control flags
100 * @buff_size: amount of bytes to be processed
101 * @fill_pattern_src_addr: Fill-Pattern or Source-Address and
102 * AW-Attributes
103 * @data_buff_addr: Source (and might be RAID6 destination)
104 * addresses of data buffers in RAID5 and RAID6
105 * @reserved: reserved
106 */
107struct mv_xor_v2_descriptor {
108	u16 desc_id;
109	u16 flags;
110	u32 crc32_result;
111	u32 desc_ctrl;
112
113	/* Definitions for desc_ctrl */
114#define DESC_NUM_ACTIVE_D_BUF_SHIFT	22
115#define DESC_OP_MODE_SHIFT		28
116#define DESC_OP_MODE_NOP		0	/* Idle operation */
117#define DESC_OP_MODE_MEMCPY		1	/* Pure-DMA operation */
118#define DESC_OP_MODE_MEMSET		2	/* Mem-Fill operation */
119#define DESC_OP_MODE_MEMINIT		3	/* Mem-Init operation */
120#define DESC_OP_MODE_MEM_COMPARE	4	/* Mem-Compare operation */
121#define DESC_OP_MODE_CRC32		5	/* CRC32 calculation */
122#define DESC_OP_MODE_XOR		6	/* RAID5 (XOR) operation */
123#define DESC_OP_MODE_RAID6		7	/* RAID6 P&Q-generation */
124#define DESC_OP_MODE_RAID6_REC		8	/* RAID6 Recovery */
125#define DESC_Q_BUFFER_ENABLE		BIT(16)
126#define DESC_P_BUFFER_ENABLE		BIT(17)
127#define DESC_IOD			BIT(27)
128
129	u32 buff_size;
130	u32 fill_pattern_src_addr[4];
131	u32 data_buff_addr[MV_XOR_V2_DESC_BUFF_D_ADDR_SIZE];
132	u32 reserved[MV_XOR_V2_DESC_RESERVED_SIZE];
133};
134
135/**
136 * struct mv_xor_v2_device - implements a xor device
137 * @lock: lock for the engine
138 * @clk: reference to the 'core' clock
139 * @reg_clk: reference to the 'reg' clock
140 * @dma_base: memory mapped DMA register base
141 * @glob_base: memory mapped global register base
142 * @irq_tasklet: tasklet used for IRQ handling call-backs
143 * @free_sw_desc: linked list of free SW descriptors
144 * @dmadev: dma device
145 * @dmachan: dma channel
146 * @hw_desq: HW descriptors queue
147 * @hw_desq_virt: virtual address of DESCQ
148 * @sw_desq: SW descriptors queue
149 * @desc_size: HW descriptor size
150 * @npendings: number of pending descriptors (for which tx_submit has
151 * @hw_queue_idx: HW queue index
152 * @irq: The Linux interrupt number
153 * been called, but not yet issue_pending)
154 */
155struct mv_xor_v2_device {
156	spinlock_t lock;
157	void __iomem *dma_base;
158	void __iomem *glob_base;
159	struct clk *clk;
160	struct clk *reg_clk;
161	struct tasklet_struct irq_tasklet;
162	struct list_head free_sw_desc;
163	struct dma_device dmadev;
164	struct dma_chan	dmachan;
165	dma_addr_t hw_desq;
166	struct mv_xor_v2_descriptor *hw_desq_virt;
167	struct mv_xor_v2_sw_desc *sw_desq;
168	int desc_size;
169	unsigned int npendings;
170	unsigned int hw_queue_idx;
171	unsigned int irq;
172};
173
174/**
175 * struct mv_xor_v2_sw_desc - implements a xor SW descriptor
176 * @idx: descriptor index
177 * @async_tx: support for the async_tx api
178 * @hw_desc: assosiated HW descriptor
179 * @free_list: node of the free SW descriprots list
180*/
181struct mv_xor_v2_sw_desc {
182	int idx;
183	struct dma_async_tx_descriptor async_tx;
184	struct mv_xor_v2_descriptor hw_desc;
185	struct list_head free_list;
186};
187
188/*
189 * Fill the data buffers to a HW descriptor
190 */
191static void mv_xor_v2_set_data_buffers(struct mv_xor_v2_device *xor_dev,
192					struct mv_xor_v2_descriptor *desc,
193					dma_addr_t src, int index)
194{
195	int arr_index = ((index >> 1) * 3);
196
197	/*
198	 * Fill the buffer's addresses to the descriptor.
199	 *
200	 * The format of the buffers address for 2 sequential buffers
201	 * X and X + 1:
202	 *
203	 *  First word:  Buffer-DX-Address-Low[31:0]
204	 *  Second word: Buffer-DX+1-Address-Low[31:0]
205	 *  Third word:  DX+1-Buffer-Address-High[47:32] [31:16]
206	 *		 DX-Buffer-Address-High[47:32] [15:0]
207	 */
208	if ((index & 0x1) == 0) {
209		desc->data_buff_addr[arr_index] = lower_32_bits(src);
210
211		desc->data_buff_addr[arr_index + 2] &= ~0xFFFF;
212		desc->data_buff_addr[arr_index + 2] |=
213			upper_32_bits(src) & 0xFFFF;
214	} else {
215		desc->data_buff_addr[arr_index + 1] =
216			lower_32_bits(src);
217
218		desc->data_buff_addr[arr_index + 2] &= ~0xFFFF0000;
219		desc->data_buff_addr[arr_index + 2] |=
220			(upper_32_bits(src) & 0xFFFF) << 16;
221	}
222}
223
224/*
225 * notify the engine of new descriptors, and update the available index.
226 */
227static void mv_xor_v2_add_desc_to_desq(struct mv_xor_v2_device *xor_dev,
228				       int num_of_desc)
229{
230	/* write the number of new descriptors in the DESQ. */
231	writel(num_of_desc, xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_ADD_OFF);
232}
233
234/*
235 * free HW descriptors
236 */
237static void mv_xor_v2_free_desc_from_desq(struct mv_xor_v2_device *xor_dev,
238					  int num_of_desc)
239{
240	/* write the number of new descriptors in the DESQ. */
241	writel(num_of_desc, xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_DEALLOC_OFF);
242}
243
244/*
245 * Set descriptor size
246 * Return the HW descriptor size in bytes
247 */
248static int mv_xor_v2_set_desc_size(struct mv_xor_v2_device *xor_dev)
249{
250	writel(MV_XOR_V2_DMA_DESQ_CTRL_128B,
251	       xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_CTRL_OFF);
252
253	return MV_XOR_V2_EXT_DESC_SIZE;
254}
255
256/*
257 * Set the IMSG threshold
258 */
259static inline
260void mv_xor_v2_enable_imsg_thrd(struct mv_xor_v2_device *xor_dev)
261{
262	u32 reg;
263
264	/* Configure threshold of number of descriptors, and enable timer */
265	reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_THRD_OFF);
266	reg &= ~MV_XOR_V2_DMA_IMSG_THRD_MASK;
267	reg |= MV_XOR_V2_DONE_IMSG_THRD;
268	reg |= MV_XOR_V2_DMA_IMSG_TIMER_EN;
269	writel(reg, xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_THRD_OFF);
270
271	/* Configure Timer Threshold */
272	reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_TMOT);
273	reg &= ~MV_XOR_V2_DMA_IMSG_TIMER_THRD_MASK;
274	reg |= MV_XOR_V2_TIMER_THRD;
275	writel(reg, xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_TMOT);
276}
277
278static irqreturn_t mv_xor_v2_interrupt_handler(int irq, void *data)
279{
280	struct mv_xor_v2_device *xor_dev = data;
281	unsigned int ndescs;
282	u32 reg;
283
284	reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_DONE_OFF);
285
286	ndescs = ((reg >> MV_XOR_V2_DMA_DESQ_DONE_PENDING_SHIFT) &
287		  MV_XOR_V2_DMA_DESQ_DONE_PENDING_MASK);
288
289	/* No descriptors to process */
290	if (!ndescs)
291		return IRQ_NONE;
292
293	/* schedule a tasklet to handle descriptors callbacks */
294	tasklet_schedule(&xor_dev->irq_tasklet);
295
296	return IRQ_HANDLED;
297}
298
299/*
300 * submit a descriptor to the DMA engine
301 */
302static dma_cookie_t
303mv_xor_v2_tx_submit(struct dma_async_tx_descriptor *tx)
304{
305	void *dest_hw_desc;
306	dma_cookie_t cookie;
307	struct mv_xor_v2_sw_desc *sw_desc =
308		container_of(tx, struct mv_xor_v2_sw_desc, async_tx);
309	struct mv_xor_v2_device *xor_dev =
310		container_of(tx->chan, struct mv_xor_v2_device, dmachan);
311
312	dev_dbg(xor_dev->dmadev.dev,
313		"%s sw_desc %p: async_tx %p\n",
314		__func__, sw_desc, &sw_desc->async_tx);
315
316	/* assign cookie */
317	spin_lock_bh(&xor_dev->lock);
318	cookie = dma_cookie_assign(tx);
319
320	/* copy the HW descriptor from the SW descriptor to the DESQ */
321	dest_hw_desc = xor_dev->hw_desq_virt + xor_dev->hw_queue_idx;
322
323	memcpy(dest_hw_desc, &sw_desc->hw_desc, xor_dev->desc_size);
324
325	xor_dev->npendings++;
326	xor_dev->hw_queue_idx++;
327	if (xor_dev->hw_queue_idx >= MV_XOR_V2_DESC_NUM)
328		xor_dev->hw_queue_idx = 0;
329
330	spin_unlock_bh(&xor_dev->lock);
331
332	return cookie;
333}
334
335/*
336 * Prepare a SW descriptor
337 */
338static struct mv_xor_v2_sw_desc	*
339mv_xor_v2_prep_sw_desc(struct mv_xor_v2_device *xor_dev)
340{
341	struct mv_xor_v2_sw_desc *sw_desc;
342	bool found = false;
343
344	/* Lock the channel */
345	spin_lock_bh(&xor_dev->lock);
346
347	if (list_empty(&xor_dev->free_sw_desc)) {
348		spin_unlock_bh(&xor_dev->lock);
349		/* schedule tasklet to free some descriptors */
350		tasklet_schedule(&xor_dev->irq_tasklet);
351		return NULL;
352	}
353
354	list_for_each_entry(sw_desc, &xor_dev->free_sw_desc, free_list) {
355		if (async_tx_test_ack(&sw_desc->async_tx)) {
356			found = true;
357			break;
358		}
359	}
360
361	if (!found) {
362		spin_unlock_bh(&xor_dev->lock);
363		return NULL;
364	}
365
366	list_del(&sw_desc->free_list);
367
368	/* Release the channel */
369	spin_unlock_bh(&xor_dev->lock);
370
371	return sw_desc;
372}
373
374/*
375 * Prepare a HW descriptor for a memcpy operation
376 */
377static struct dma_async_tx_descriptor *
378mv_xor_v2_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest,
379			  dma_addr_t src, size_t len, unsigned long flags)
380{
381	struct mv_xor_v2_sw_desc *sw_desc;
382	struct mv_xor_v2_descriptor *hw_descriptor;
383	struct mv_xor_v2_device	*xor_dev;
384
385	xor_dev = container_of(chan, struct mv_xor_v2_device, dmachan);
386
387	dev_dbg(xor_dev->dmadev.dev,
388		"%s len: %zu src %pad dest %pad flags: %ld\n",
389		__func__, len, &src, &dest, flags);
390
391	sw_desc = mv_xor_v2_prep_sw_desc(xor_dev);
392	if (!sw_desc)
393		return NULL;
394
395	sw_desc->async_tx.flags = flags;
396
397	/* set the HW descriptor */
398	hw_descriptor = &sw_desc->hw_desc;
399
400	/* save the SW descriptor ID to restore when operation is done */
401	hw_descriptor->desc_id = sw_desc->idx;
402
403	/* Set the MEMCPY control word */
404	hw_descriptor->desc_ctrl =
405		DESC_OP_MODE_MEMCPY << DESC_OP_MODE_SHIFT;
406
407	if (flags & DMA_PREP_INTERRUPT)
408		hw_descriptor->desc_ctrl |= DESC_IOD;
409
410	/* Set source address */
411	hw_descriptor->fill_pattern_src_addr[0] = lower_32_bits(src);
412	hw_descriptor->fill_pattern_src_addr[1] =
413		upper_32_bits(src) & 0xFFFF;
414
415	/* Set Destination address */
416	hw_descriptor->fill_pattern_src_addr[2] = lower_32_bits(dest);
417	hw_descriptor->fill_pattern_src_addr[3] =
418		upper_32_bits(dest) & 0xFFFF;
419
420	/* Set buffers size */
421	hw_descriptor->buff_size = len;
422
423	/* return the async tx descriptor */
424	return &sw_desc->async_tx;
425}
426
427/*
428 * Prepare a HW descriptor for a XOR operation
429 */
430static struct dma_async_tx_descriptor *
431mv_xor_v2_prep_dma_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
432		       unsigned int src_cnt, size_t len, unsigned long flags)
433{
434	struct mv_xor_v2_sw_desc *sw_desc;
435	struct mv_xor_v2_descriptor *hw_descriptor;
436	struct mv_xor_v2_device	*xor_dev =
437		container_of(chan, struct mv_xor_v2_device, dmachan);
438	int i;
439
440	if (src_cnt > MV_XOR_V2_CMD_LINE_NUM_MAX_D_BUF || src_cnt < 1)
441		return NULL;
442
443	dev_dbg(xor_dev->dmadev.dev,
444		"%s src_cnt: %d len: %zu dest %pad flags: %ld\n",
445		__func__, src_cnt, len, &dest, flags);
446
447	sw_desc = mv_xor_v2_prep_sw_desc(xor_dev);
448	if (!sw_desc)
449		return NULL;
450
451	sw_desc->async_tx.flags = flags;
452
453	/* set the HW descriptor */
454	hw_descriptor = &sw_desc->hw_desc;
455
456	/* save the SW descriptor ID to restore when operation is done */
457	hw_descriptor->desc_id = sw_desc->idx;
458
459	/* Set the XOR control word */
460	hw_descriptor->desc_ctrl =
461		DESC_OP_MODE_XOR << DESC_OP_MODE_SHIFT;
462	hw_descriptor->desc_ctrl |= DESC_P_BUFFER_ENABLE;
463
464	if (flags & DMA_PREP_INTERRUPT)
465		hw_descriptor->desc_ctrl |= DESC_IOD;
466
467	/* Set the data buffers */
468	for (i = 0; i < src_cnt; i++)
469		mv_xor_v2_set_data_buffers(xor_dev, hw_descriptor, src[i], i);
470
471	hw_descriptor->desc_ctrl |=
472		src_cnt << DESC_NUM_ACTIVE_D_BUF_SHIFT;
473
474	/* Set Destination address */
475	hw_descriptor->fill_pattern_src_addr[2] = lower_32_bits(dest);
476	hw_descriptor->fill_pattern_src_addr[3] =
477		upper_32_bits(dest) & 0xFFFF;
478
479	/* Set buffers size */
480	hw_descriptor->buff_size = len;
481
482	/* return the async tx descriptor */
483	return &sw_desc->async_tx;
484}
485
486/*
487 * Prepare a HW descriptor for interrupt operation.
488 */
489static struct dma_async_tx_descriptor *
490mv_xor_v2_prep_dma_interrupt(struct dma_chan *chan, unsigned long flags)
491{
492	struct mv_xor_v2_sw_desc *sw_desc;
493	struct mv_xor_v2_descriptor *hw_descriptor;
494	struct mv_xor_v2_device	*xor_dev =
495		container_of(chan, struct mv_xor_v2_device, dmachan);
496
497	sw_desc = mv_xor_v2_prep_sw_desc(xor_dev);
498	if (!sw_desc)
499		return NULL;
500
501	/* set the HW descriptor */
502	hw_descriptor = &sw_desc->hw_desc;
503
504	/* save the SW descriptor ID to restore when operation is done */
505	hw_descriptor->desc_id = sw_desc->idx;
506
507	/* Set the INTERRUPT control word */
508	hw_descriptor->desc_ctrl =
509		DESC_OP_MODE_NOP << DESC_OP_MODE_SHIFT;
510	hw_descriptor->desc_ctrl |= DESC_IOD;
511
512	/* return the async tx descriptor */
513	return &sw_desc->async_tx;
514}
515
516/*
517 * push pending transactions to hardware
518 */
519static void mv_xor_v2_issue_pending(struct dma_chan *chan)
520{
521	struct mv_xor_v2_device *xor_dev =
522		container_of(chan, struct mv_xor_v2_device, dmachan);
523
524	spin_lock_bh(&xor_dev->lock);
525
526	/*
527	 * update the engine with the number of descriptors to
528	 * process
529	 */
530	mv_xor_v2_add_desc_to_desq(xor_dev, xor_dev->npendings);
531	xor_dev->npendings = 0;
532
533	spin_unlock_bh(&xor_dev->lock);
534}
535
536static inline
537int mv_xor_v2_get_pending_params(struct mv_xor_v2_device *xor_dev,
538				 int *pending_ptr)
539{
540	u32 reg;
541
542	reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_DONE_OFF);
543
544	/* get the next pending descriptor index */
545	*pending_ptr = ((reg >> MV_XOR_V2_DMA_DESQ_DONE_READ_PTR_SHIFT) &
546			MV_XOR_V2_DMA_DESQ_DONE_READ_PTR_MASK);
547
548	/* get the number of descriptors pending handle */
549	return ((reg >> MV_XOR_V2_DMA_DESQ_DONE_PENDING_SHIFT) &
550		MV_XOR_V2_DMA_DESQ_DONE_PENDING_MASK);
551}
552
553/*
554 * handle the descriptors after HW process
555 */
556static void mv_xor_v2_tasklet(struct tasklet_struct *t)
557{
558	struct mv_xor_v2_device *xor_dev = from_tasklet(xor_dev, t,
559							irq_tasklet);
560	int pending_ptr, num_of_pending, i;
561	struct mv_xor_v2_sw_desc *next_pending_sw_desc = NULL;
562
563	dev_dbg(xor_dev->dmadev.dev, "%s %d\n", __func__, __LINE__);
564
565	/* get the pending descriptors parameters */
566	num_of_pending = mv_xor_v2_get_pending_params(xor_dev, &pending_ptr);
567
568	/* loop over free descriptors */
569	for (i = 0; i < num_of_pending; i++) {
570		struct mv_xor_v2_descriptor *next_pending_hw_desc =
571			xor_dev->hw_desq_virt + pending_ptr;
572
573		/* get the SW descriptor related to the HW descriptor */
574		next_pending_sw_desc =
575			&xor_dev->sw_desq[next_pending_hw_desc->desc_id];
576
577		/* call the callback */
578		if (next_pending_sw_desc->async_tx.cookie > 0) {
579			/*
580			 * update the channel's completed cookie - no
581			 * lock is required the IMSG threshold provide
582			 * the locking
583			 */
584			dma_cookie_complete(&next_pending_sw_desc->async_tx);
585
586			dma_descriptor_unmap(&next_pending_sw_desc->async_tx);
587			dmaengine_desc_get_callback_invoke(
588					&next_pending_sw_desc->async_tx, NULL);
589		}
590
591		dma_run_dependencies(&next_pending_sw_desc->async_tx);
592
593		/* Lock the channel */
594		spin_lock(&xor_dev->lock);
595
596		/* add the SW descriptor to the free descriptors list */
597		list_add(&next_pending_sw_desc->free_list,
598			 &xor_dev->free_sw_desc);
599
600		/* Release the channel */
601		spin_unlock(&xor_dev->lock);
602
603		/* increment the next descriptor */
604		pending_ptr++;
605		if (pending_ptr >= MV_XOR_V2_DESC_NUM)
606			pending_ptr = 0;
607	}
608
609	if (num_of_pending != 0) {
610		/* free the descriptores */
611		mv_xor_v2_free_desc_from_desq(xor_dev, num_of_pending);
612	}
613}
614
615/*
616 *	Set DMA Interrupt-message (IMSG) parameters
617 */
618static void mv_xor_v2_set_msi_msg(struct msi_desc *desc, struct msi_msg *msg)
619{
620	struct mv_xor_v2_device *xor_dev = dev_get_drvdata(desc->dev);
621
622	writel(msg->address_lo,
623	       xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_BALR_OFF);
624	writel(msg->address_hi & 0xFFFF,
625	       xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_BAHR_OFF);
626	writel(msg->data,
627	       xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_CDAT_OFF);
628}
629
630static int mv_xor_v2_descq_init(struct mv_xor_v2_device *xor_dev)
631{
632	u32 reg;
633
634	/* write the DESQ size to the DMA engine */
635	writel(MV_XOR_V2_DESC_NUM,
636	       xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_SIZE_OFF);
637
638	/* write the DESQ address to the DMA enngine*/
639	writel(lower_32_bits(xor_dev->hw_desq),
640	       xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_BALR_OFF);
641	writel(upper_32_bits(xor_dev->hw_desq),
642	       xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_BAHR_OFF);
643
644	/*
645	 * This is a temporary solution, until we activate the
646	 * SMMU. Set the attributes for reading & writing data buffers
647	 * & descriptors to:
648	 *
649	 *  - OuterShareable - Snoops will be performed on CPU caches
650	 *  - Enable cacheable - Bufferable, Modifiable, Other Allocate
651	 *    and Allocate
652	 */
653	reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_ARATTR_OFF);
654	reg &= ~MV_XOR_V2_DMA_DESQ_ATTR_CACHE_MASK;
655	reg |= MV_XOR_V2_DMA_DESQ_ATTR_OUTER_SHAREABLE |
656		MV_XOR_V2_DMA_DESQ_ATTR_CACHEABLE;
657	writel(reg, xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_ARATTR_OFF);
658
659	reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_AWATTR_OFF);
660	reg &= ~MV_XOR_V2_DMA_DESQ_ATTR_CACHE_MASK;
661	reg |= MV_XOR_V2_DMA_DESQ_ATTR_OUTER_SHAREABLE |
662		MV_XOR_V2_DMA_DESQ_ATTR_CACHEABLE;
663	writel(reg, xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_AWATTR_OFF);
664
665	/* BW CTRL - set values to optimize the XOR performance:
666	 *
667	 *  - Set WrBurstLen & RdBurstLen - the unit will issue
668	 *    maximum of 256B write/read transactions.
669	 * -  Limit the number of outstanding write & read data
670	 *    (OBB/IBB) requests to the maximal value.
671	*/
672	reg = ((MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_RD_VAL <<
673		MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_RD_SHIFT) |
674	       (MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_WR_VAL  <<
675		MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_WR_SHIFT) |
676	       (MV_XOR_V2_GLOB_BW_CTRL_RD_BURST_LEN_VAL <<
677		MV_XOR_V2_GLOB_BW_CTRL_RD_BURST_LEN_SHIFT) |
678	       (MV_XOR_V2_GLOB_BW_CTRL_WR_BURST_LEN_VAL <<
679		MV_XOR_V2_GLOB_BW_CTRL_WR_BURST_LEN_SHIFT));
680	writel(reg, xor_dev->glob_base + MV_XOR_V2_GLOB_BW_CTRL);
681
682	/* Disable the AXI timer feature */
683	reg = readl(xor_dev->glob_base + MV_XOR_V2_GLOB_PAUSE);
684	reg |= MV_XOR_V2_GLOB_PAUSE_AXI_TIME_DIS_VAL;
685	writel(reg, xor_dev->glob_base + MV_XOR_V2_GLOB_PAUSE);
686
687	/* enable the DMA engine */
688	writel(0, xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_STOP_OFF);
689
690	return 0;
691}
692
693static int mv_xor_v2_suspend(struct platform_device *dev, pm_message_t state)
694{
695	struct mv_xor_v2_device *xor_dev = platform_get_drvdata(dev);
696
697	/* Set this bit to disable to stop the XOR unit. */
698	writel(0x1, xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_STOP_OFF);
699
700	return 0;
701}
702
703static int mv_xor_v2_resume(struct platform_device *dev)
704{
705	struct mv_xor_v2_device *xor_dev = platform_get_drvdata(dev);
706
707	mv_xor_v2_set_desc_size(xor_dev);
708	mv_xor_v2_enable_imsg_thrd(xor_dev);
709	mv_xor_v2_descq_init(xor_dev);
710
711	return 0;
712}
713
714static int mv_xor_v2_probe(struct platform_device *pdev)
715{
716	struct mv_xor_v2_device *xor_dev;
717	int i, ret = 0;
718	struct dma_device *dma_dev;
719	struct mv_xor_v2_sw_desc *sw_desc;
720
721	BUILD_BUG_ON(sizeof(struct mv_xor_v2_descriptor) !=
722		     MV_XOR_V2_EXT_DESC_SIZE);
723
724	xor_dev = devm_kzalloc(&pdev->dev, sizeof(*xor_dev), GFP_KERNEL);
725	if (!xor_dev)
726		return -ENOMEM;
727
728	xor_dev->dma_base = devm_platform_ioremap_resource(pdev, 0);
729	if (IS_ERR(xor_dev->dma_base))
730		return PTR_ERR(xor_dev->dma_base);
731
732	xor_dev->glob_base = devm_platform_ioremap_resource(pdev, 1);
733	if (IS_ERR(xor_dev->glob_base))
734		return PTR_ERR(xor_dev->glob_base);
735
736	platform_set_drvdata(pdev, xor_dev);
737
738	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(40));
739	if (ret)
740		return ret;
741
742	xor_dev->reg_clk = devm_clk_get_optional_enabled(&pdev->dev, "reg");
743	if (IS_ERR(xor_dev->reg_clk))
744		return PTR_ERR(xor_dev->reg_clk);
745
746	xor_dev->clk = devm_clk_get_enabled(&pdev->dev, NULL);
747	if (IS_ERR(xor_dev->clk))
748		return PTR_ERR(xor_dev->clk);
749
750	ret = platform_device_msi_init_and_alloc_irqs(&pdev->dev, 1,
751						      mv_xor_v2_set_msi_msg);
752	if (ret)
753		return ret;
754
755	xor_dev->irq = msi_get_virq(&pdev->dev, 0);
756
757	ret = devm_request_irq(&pdev->dev, xor_dev->irq,
758			       mv_xor_v2_interrupt_handler, 0,
759			       dev_name(&pdev->dev), xor_dev);
760	if (ret)
761		goto free_msi_irqs;
762
763	tasklet_setup(&xor_dev->irq_tasklet, mv_xor_v2_tasklet);
764
765	xor_dev->desc_size = mv_xor_v2_set_desc_size(xor_dev);
766
767	dma_cookie_init(&xor_dev->dmachan);
768
769	/*
770	 * allocate coherent memory for hardware descriptors
771	 * note: writecombine gives slightly better performance, but
772	 * requires that we explicitly flush the writes
773	 */
774	xor_dev->hw_desq_virt =
775		dma_alloc_coherent(&pdev->dev,
776				   xor_dev->desc_size * MV_XOR_V2_DESC_NUM,
777				   &xor_dev->hw_desq, GFP_KERNEL);
778	if (!xor_dev->hw_desq_virt) {
779		ret = -ENOMEM;
780		goto free_msi_irqs;
781	}
782
783	/* alloc memory for the SW descriptors */
784	xor_dev->sw_desq = devm_kcalloc(&pdev->dev,
785					MV_XOR_V2_DESC_NUM, sizeof(*sw_desc),
786					GFP_KERNEL);
787	if (!xor_dev->sw_desq) {
788		ret = -ENOMEM;
789		goto free_hw_desq;
790	}
791
792	spin_lock_init(&xor_dev->lock);
793
794	/* init the free SW descriptors list */
795	INIT_LIST_HEAD(&xor_dev->free_sw_desc);
796
797	/* add all SW descriptors to the free list */
798	for (i = 0; i < MV_XOR_V2_DESC_NUM; i++) {
799		struct mv_xor_v2_sw_desc *sw_desc =
800			xor_dev->sw_desq + i;
801		sw_desc->idx = i;
802		dma_async_tx_descriptor_init(&sw_desc->async_tx,
803					     &xor_dev->dmachan);
804		sw_desc->async_tx.tx_submit = mv_xor_v2_tx_submit;
805		async_tx_ack(&sw_desc->async_tx);
806
807		list_add(&sw_desc->free_list,
808			 &xor_dev->free_sw_desc);
809	}
810
811	dma_dev = &xor_dev->dmadev;
812
813	/* set DMA capabilities */
814	dma_cap_zero(dma_dev->cap_mask);
815	dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
816	dma_cap_set(DMA_XOR, dma_dev->cap_mask);
817	dma_cap_set(DMA_INTERRUPT, dma_dev->cap_mask);
818
819	/* init dma link list */
820	INIT_LIST_HEAD(&dma_dev->channels);
821
822	/* set base routines */
823	dma_dev->device_tx_status = dma_cookie_status;
824	dma_dev->device_issue_pending = mv_xor_v2_issue_pending;
825	dma_dev->dev = &pdev->dev;
826
827	dma_dev->device_prep_dma_memcpy = mv_xor_v2_prep_dma_memcpy;
828	dma_dev->device_prep_dma_interrupt = mv_xor_v2_prep_dma_interrupt;
829	dma_dev->max_xor = 8;
830	dma_dev->device_prep_dma_xor = mv_xor_v2_prep_dma_xor;
831
832	xor_dev->dmachan.device = dma_dev;
833
834	list_add_tail(&xor_dev->dmachan.device_node,
835		      &dma_dev->channels);
836
837	mv_xor_v2_enable_imsg_thrd(xor_dev);
838
839	mv_xor_v2_descq_init(xor_dev);
840
841	ret = dma_async_device_register(dma_dev);
842	if (ret)
843		goto free_hw_desq;
844
845	dev_notice(&pdev->dev, "Marvell Version 2 XOR driver\n");
846
847	return 0;
848
849free_hw_desq:
850	dma_free_coherent(&pdev->dev,
851			  xor_dev->desc_size * MV_XOR_V2_DESC_NUM,
852			  xor_dev->hw_desq_virt, xor_dev->hw_desq);
853free_msi_irqs:
854	platform_device_msi_free_irqs_all(&pdev->dev);
855	return ret;
856}
857
858static void mv_xor_v2_remove(struct platform_device *pdev)
859{
860	struct mv_xor_v2_device *xor_dev = platform_get_drvdata(pdev);
861
862	dma_async_device_unregister(&xor_dev->dmadev);
863
864	dma_free_coherent(&pdev->dev,
865			  xor_dev->desc_size * MV_XOR_V2_DESC_NUM,
866			  xor_dev->hw_desq_virt, xor_dev->hw_desq);
867
868	devm_free_irq(&pdev->dev, xor_dev->irq, xor_dev);
869
870	platform_device_msi_free_irqs_all(&pdev->dev);
871
872	tasklet_kill(&xor_dev->irq_tasklet);
873}
874
875#ifdef CONFIG_OF
876static const struct of_device_id mv_xor_v2_dt_ids[] = {
877	{ .compatible = "marvell,xor-v2", },
878	{},
879};
880MODULE_DEVICE_TABLE(of, mv_xor_v2_dt_ids);
881#endif
882
883static struct platform_driver mv_xor_v2_driver = {
884	.probe		= mv_xor_v2_probe,
885	.suspend	= mv_xor_v2_suspend,
886	.resume		= mv_xor_v2_resume,
887	.remove_new	= mv_xor_v2_remove,
888	.driver		= {
889		.name	= "mv_xor_v2",
890		.of_match_table = of_match_ptr(mv_xor_v2_dt_ids),
891	},
892};
893
894module_platform_driver(mv_xor_v2_driver);
895
896MODULE_DESCRIPTION("DMA engine driver for Marvell's Version 2 of XOR engine");
897