mm: vma_adjust: remove superfluous check for next not NULL
[linux/fpc-iii.git] / drivers / dma / xilinx / zynqmp_dma.c
blob6d221e5c72ee116511a4c2d7459e066ab1a6ba30
1 /*
2 * DMA driver for Xilinx ZynqMP DMA Engine
4 * Copyright (C) 2016 Xilinx, Inc. All rights reserved.
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 2 of the License, or
9 * (at your option) any later version.
12 #include <linux/bitops.h>
13 #include <linux/dmapool.h>
14 #include <linux/dma/xilinx_dma.h>
15 #include <linux/init.h>
16 #include <linux/interrupt.h>
17 #include <linux/io.h>
18 #include <linux/module.h>
19 #include <linux/of_address.h>
20 #include <linux/of_dma.h>
21 #include <linux/of_irq.h>
22 #include <linux/of_platform.h>
23 #include <linux/slab.h>
24 #include <linux/clk.h>
25 #include <linux/io-64-nonatomic-lo-hi.h>
27 #include "../dmaengine.h"
29 /* Register Offsets */
30 #define ZYNQMP_DMA_ISR 0x100
31 #define ZYNQMP_DMA_IMR 0x104
32 #define ZYNQMP_DMA_IER 0x108
33 #define ZYNQMP_DMA_IDS 0x10C
34 #define ZYNQMP_DMA_CTRL0 0x110
35 #define ZYNQMP_DMA_CTRL1 0x114
36 #define ZYNQMP_DMA_DATA_ATTR 0x120
37 #define ZYNQMP_DMA_DSCR_ATTR 0x124
38 #define ZYNQMP_DMA_SRC_DSCR_WRD0 0x128
39 #define ZYNQMP_DMA_SRC_DSCR_WRD1 0x12C
40 #define ZYNQMP_DMA_SRC_DSCR_WRD2 0x130
41 #define ZYNQMP_DMA_SRC_DSCR_WRD3 0x134
42 #define ZYNQMP_DMA_DST_DSCR_WRD0 0x138
43 #define ZYNQMP_DMA_DST_DSCR_WRD1 0x13C
44 #define ZYNQMP_DMA_DST_DSCR_WRD2 0x140
45 #define ZYNQMP_DMA_DST_DSCR_WRD3 0x144
46 #define ZYNQMP_DMA_SRC_START_LSB 0x158
47 #define ZYNQMP_DMA_SRC_START_MSB 0x15C
48 #define ZYNQMP_DMA_DST_START_LSB 0x160
49 #define ZYNQMP_DMA_DST_START_MSB 0x164
50 #define ZYNQMP_DMA_RATE_CTRL 0x18C
51 #define ZYNQMP_DMA_IRQ_SRC_ACCT 0x190
52 #define ZYNQMP_DMA_IRQ_DST_ACCT 0x194
53 #define ZYNQMP_DMA_CTRL2 0x200
55 /* Interrupt registers bit field definitions */
56 #define ZYNQMP_DMA_DONE BIT(10)
57 #define ZYNQMP_DMA_AXI_WR_DATA BIT(9)
58 #define ZYNQMP_DMA_AXI_RD_DATA BIT(8)
59 #define ZYNQMP_DMA_AXI_RD_DST_DSCR BIT(7)
60 #define ZYNQMP_DMA_AXI_RD_SRC_DSCR BIT(6)
61 #define ZYNQMP_DMA_IRQ_DST_ACCT_ERR BIT(5)
62 #define ZYNQMP_DMA_IRQ_SRC_ACCT_ERR BIT(4)
63 #define ZYNQMP_DMA_BYTE_CNT_OVRFL BIT(3)
64 #define ZYNQMP_DMA_DST_DSCR_DONE BIT(2)
65 #define ZYNQMP_DMA_INV_APB BIT(0)
67 /* Control 0 register bit field definitions */
68 #define ZYNQMP_DMA_OVR_FETCH BIT(7)
69 #define ZYNQMP_DMA_POINT_TYPE_SG BIT(6)
70 #define ZYNQMP_DMA_RATE_CTRL_EN BIT(3)
72 /* Control 1 register bit field definitions */
73 #define ZYNQMP_DMA_SRC_ISSUE GENMASK(4, 0)
75 /* Data Attribute register bit field definitions */
76 #define ZYNQMP_DMA_ARBURST GENMASK(27, 26)
77 #define ZYNQMP_DMA_ARCACHE GENMASK(25, 22)
78 #define ZYNQMP_DMA_ARCACHE_OFST 22
79 #define ZYNQMP_DMA_ARQOS GENMASK(21, 18)
80 #define ZYNQMP_DMA_ARQOS_OFST 18
81 #define ZYNQMP_DMA_ARLEN GENMASK(17, 14)
82 #define ZYNQMP_DMA_ARLEN_OFST 14
83 #define ZYNQMP_DMA_AWBURST GENMASK(13, 12)
84 #define ZYNQMP_DMA_AWCACHE GENMASK(11, 8)
85 #define ZYNQMP_DMA_AWCACHE_OFST 8
86 #define ZYNQMP_DMA_AWQOS GENMASK(7, 4)
87 #define ZYNQMP_DMA_AWQOS_OFST 4
88 #define ZYNQMP_DMA_AWLEN GENMASK(3, 0)
89 #define ZYNQMP_DMA_AWLEN_OFST 0
91 /* Descriptor Attribute register bit field definitions */
92 #define ZYNQMP_DMA_AXCOHRNT BIT(8)
93 #define ZYNQMP_DMA_AXCACHE GENMASK(7, 4)
94 #define ZYNQMP_DMA_AXCACHE_OFST 4
95 #define ZYNQMP_DMA_AXQOS GENMASK(3, 0)
96 #define ZYNQMP_DMA_AXQOS_OFST 0
98 /* Control register 2 bit field definitions */
99 #define ZYNQMP_DMA_ENABLE BIT(0)
101 /* Buffer Descriptor definitions */
102 #define ZYNQMP_DMA_DESC_CTRL_STOP 0x10
103 #define ZYNQMP_DMA_DESC_CTRL_COMP_INT 0x4
104 #define ZYNQMP_DMA_DESC_CTRL_SIZE_256 0x2
105 #define ZYNQMP_DMA_DESC_CTRL_COHRNT 0x1
107 /* Interrupt Mask specific definitions */
108 #define ZYNQMP_DMA_INT_ERR (ZYNQMP_DMA_AXI_RD_DATA | \
109 ZYNQMP_DMA_AXI_WR_DATA | \
110 ZYNQMP_DMA_AXI_RD_DST_DSCR | \
111 ZYNQMP_DMA_AXI_RD_SRC_DSCR | \
112 ZYNQMP_DMA_INV_APB)
113 #define ZYNQMP_DMA_INT_OVRFL (ZYNQMP_DMA_BYTE_CNT_OVRFL | \
114 ZYNQMP_DMA_IRQ_SRC_ACCT_ERR | \
115 ZYNQMP_DMA_IRQ_DST_ACCT_ERR)
116 #define ZYNQMP_DMA_INT_DONE (ZYNQMP_DMA_DONE | ZYNQMP_DMA_DST_DSCR_DONE)
117 #define ZYNQMP_DMA_INT_EN_DEFAULT_MASK (ZYNQMP_DMA_INT_DONE | \
118 ZYNQMP_DMA_INT_ERR | \
119 ZYNQMP_DMA_INT_OVRFL | \
120 ZYNQMP_DMA_DST_DSCR_DONE)
122 /* Max number of descriptors per channel */
123 #define ZYNQMP_DMA_NUM_DESCS 32
125 /* Max transfer size per descriptor */
126 #define ZYNQMP_DMA_MAX_TRANS_LEN 0x40000000
128 /* Reset values for data attributes */
129 #define ZYNQMP_DMA_AXCACHE_VAL 0xF
130 #define ZYNQMP_DMA_ARLEN_RST_VAL 0xF
131 #define ZYNQMP_DMA_AWLEN_RST_VAL 0xF
133 #define ZYNQMP_DMA_SRC_ISSUE_RST_VAL 0x1F
135 #define ZYNQMP_DMA_IDS_DEFAULT_MASK 0xFFF
137 /* Bus width in bits */
138 #define ZYNQMP_DMA_BUS_WIDTH_64 64
139 #define ZYNQMP_DMA_BUS_WIDTH_128 128
141 #define ZYNQMP_DMA_DESC_SIZE(chan) (chan->desc_size)
143 #define to_chan(chan) container_of(chan, struct zynqmp_dma_chan, \
144 common)
145 #define tx_to_desc(tx) container_of(tx, struct zynqmp_dma_desc_sw, \
146 async_tx)
149 * struct zynqmp_dma_desc_ll - Hw linked list descriptor
150 * @addr: Buffer address
151 * @size: Size of the buffer
152 * @ctrl: Control word
153 * @nxtdscraddr: Next descriptor base address
154 * @rsvd: Reserved field and for Hw internal use.
156 struct zynqmp_dma_desc_ll {
157 u64 addr;
158 u32 size;
159 u32 ctrl;
160 u64 nxtdscraddr;
161 u64 rsvd;
162 }; __aligned(64)
165 * struct zynqmp_dma_desc_sw - Per Transaction structure
166 * @src: Source address for simple mode dma
167 * @dst: Destination address for simple mode dma
168 * @len: Transfer length for simple mode dma
169 * @node: Node in the channel descriptor list
170 * @tx_list: List head for the current transfer
171 * @async_tx: Async transaction descriptor
172 * @src_v: Virtual address of the src descriptor
173 * @src_p: Physical address of the src descriptor
174 * @dst_v: Virtual address of the dst descriptor
175 * @dst_p: Physical address of the dst descriptor
177 struct zynqmp_dma_desc_sw {
178 u64 src;
179 u64 dst;
180 u32 len;
181 struct list_head node;
182 struct list_head tx_list;
183 struct dma_async_tx_descriptor async_tx;
184 struct zynqmp_dma_desc_ll *src_v;
185 dma_addr_t src_p;
186 struct zynqmp_dma_desc_ll *dst_v;
187 dma_addr_t dst_p;
191 * struct zynqmp_dma_chan - Driver specific DMA channel structure
192 * @zdev: Driver specific device structure
193 * @regs: Control registers offset
194 * @lock: Descriptor operation lock
195 * @pending_list: Descriptors waiting
196 * @free_list: Descriptors free
197 * @active_list: Descriptors active
198 * @sw_desc_pool: SW descriptor pool
199 * @done_list: Complete descriptors
200 * @common: DMA common channel
201 * @desc_pool_v: Statically allocated descriptor base
202 * @desc_pool_p: Physical allocated descriptor base
203 * @desc_free_cnt: Descriptor available count
204 * @dev: The dma device
205 * @irq: Channel IRQ
206 * @is_dmacoherent: Tells whether dma operations are coherent or not
207 * @tasklet: Cleanup work after irq
208 * @idle : Channel status;
209 * @desc_size: Size of the low level descriptor
210 * @err: Channel has errors
211 * @bus_width: Bus width
212 * @src_burst_len: Source burst length
213 * @dst_burst_len: Dest burst length
214 * @clk_main: Pointer to main clock
215 * @clk_apb: Pointer to apb clock
217 struct zynqmp_dma_chan {
218 struct zynqmp_dma_device *zdev;
219 void __iomem *regs;
220 spinlock_t lock;
221 struct list_head pending_list;
222 struct list_head free_list;
223 struct list_head active_list;
224 struct zynqmp_dma_desc_sw *sw_desc_pool;
225 struct list_head done_list;
226 struct dma_chan common;
227 void *desc_pool_v;
228 dma_addr_t desc_pool_p;
229 u32 desc_free_cnt;
230 struct device *dev;
231 int irq;
232 bool is_dmacoherent;
233 struct tasklet_struct tasklet;
234 bool idle;
235 u32 desc_size;
236 bool err;
237 u32 bus_width;
238 u32 src_burst_len;
239 u32 dst_burst_len;
240 struct clk *clk_main;
241 struct clk *clk_apb;
245 * struct zynqmp_dma_device - DMA device structure
246 * @dev: Device Structure
247 * @common: DMA device structure
248 * @chan: Driver specific DMA channel
250 struct zynqmp_dma_device {
251 struct device *dev;
252 struct dma_device common;
253 struct zynqmp_dma_chan *chan;
256 static inline void zynqmp_dma_writeq(struct zynqmp_dma_chan *chan, u32 reg,
257 u64 value)
259 lo_hi_writeq(value, chan->regs + reg);
263 * zynqmp_dma_update_desc_to_ctrlr - Updates descriptor to the controller
264 * @chan: ZynqMP DMA DMA channel pointer
265 * @desc: Transaction descriptor pointer
267 static void zynqmp_dma_update_desc_to_ctrlr(struct zynqmp_dma_chan *chan,
268 struct zynqmp_dma_desc_sw *desc)
270 dma_addr_t addr;
272 addr = desc->src_p;
273 zynqmp_dma_writeq(chan, ZYNQMP_DMA_SRC_START_LSB, addr);
274 addr = desc->dst_p;
275 zynqmp_dma_writeq(chan, ZYNQMP_DMA_DST_START_LSB, addr);
279 * zynqmp_dma_desc_config_eod - Mark the descriptor as end descriptor
280 * @chan: ZynqMP DMA channel pointer
281 * @desc: Hw descriptor pointer
283 static void zynqmp_dma_desc_config_eod(struct zynqmp_dma_chan *chan,
284 void *desc)
286 struct zynqmp_dma_desc_ll *hw = (struct zynqmp_dma_desc_ll *)desc;
288 hw->ctrl |= ZYNQMP_DMA_DESC_CTRL_STOP;
289 hw++;
290 hw->ctrl |= ZYNQMP_DMA_DESC_CTRL_COMP_INT | ZYNQMP_DMA_DESC_CTRL_STOP;
294 * zynqmp_dma_config_sg_ll_desc - Configure the linked list descriptor
295 * @chan: ZynqMP DMA channel pointer
296 * @sdesc: Hw descriptor pointer
297 * @src: Source buffer address
298 * @dst: Destination buffer address
299 * @len: Transfer length
300 * @prev: Previous hw descriptor pointer
302 static void zynqmp_dma_config_sg_ll_desc(struct zynqmp_dma_chan *chan,
303 struct zynqmp_dma_desc_ll *sdesc,
304 dma_addr_t src, dma_addr_t dst, size_t len,
305 struct zynqmp_dma_desc_ll *prev)
307 struct zynqmp_dma_desc_ll *ddesc = sdesc + 1;
309 sdesc->size = ddesc->size = len;
310 sdesc->addr = src;
311 ddesc->addr = dst;
313 sdesc->ctrl = ddesc->ctrl = ZYNQMP_DMA_DESC_CTRL_SIZE_256;
314 if (chan->is_dmacoherent) {
315 sdesc->ctrl |= ZYNQMP_DMA_DESC_CTRL_COHRNT;
316 ddesc->ctrl |= ZYNQMP_DMA_DESC_CTRL_COHRNT;
319 if (prev) {
320 dma_addr_t addr = chan->desc_pool_p +
321 ((uintptr_t)sdesc - (uintptr_t)chan->desc_pool_v);
322 ddesc = prev + 1;
323 prev->nxtdscraddr = addr;
324 ddesc->nxtdscraddr = addr + ZYNQMP_DMA_DESC_SIZE(chan);
329 * zynqmp_dma_init - Initialize the channel
330 * @chan: ZynqMP DMA channel pointer
332 static void zynqmp_dma_init(struct zynqmp_dma_chan *chan)
334 u32 val;
336 writel(ZYNQMP_DMA_IDS_DEFAULT_MASK, chan->regs + ZYNQMP_DMA_IDS);
337 val = readl(chan->regs + ZYNQMP_DMA_ISR);
338 writel(val, chan->regs + ZYNQMP_DMA_ISR);
340 if (chan->is_dmacoherent) {
341 val = ZYNQMP_DMA_AXCOHRNT;
342 val = (val & ~ZYNQMP_DMA_AXCACHE) |
343 (ZYNQMP_DMA_AXCACHE_VAL << ZYNQMP_DMA_AXCACHE_OFST);
344 writel(val, chan->regs + ZYNQMP_DMA_DSCR_ATTR);
347 val = readl(chan->regs + ZYNQMP_DMA_DATA_ATTR);
348 if (chan->is_dmacoherent) {
349 val = (val & ~ZYNQMP_DMA_ARCACHE) |
350 (ZYNQMP_DMA_AXCACHE_VAL << ZYNQMP_DMA_ARCACHE_OFST);
351 val = (val & ~ZYNQMP_DMA_AWCACHE) |
352 (ZYNQMP_DMA_AXCACHE_VAL << ZYNQMP_DMA_AWCACHE_OFST);
354 writel(val, chan->regs + ZYNQMP_DMA_DATA_ATTR);
356 /* Clearing the interrupt account rgisters */
357 val = readl(chan->regs + ZYNQMP_DMA_IRQ_SRC_ACCT);
358 val = readl(chan->regs + ZYNQMP_DMA_IRQ_DST_ACCT);
360 chan->idle = true;
364 * zynqmp_dma_tx_submit - Submit DMA transaction
365 * @tx: Async transaction descriptor pointer
367 * Return: cookie value
369 static dma_cookie_t zynqmp_dma_tx_submit(struct dma_async_tx_descriptor *tx)
371 struct zynqmp_dma_chan *chan = to_chan(tx->chan);
372 struct zynqmp_dma_desc_sw *desc, *new;
373 dma_cookie_t cookie;
375 new = tx_to_desc(tx);
376 spin_lock_bh(&chan->lock);
377 cookie = dma_cookie_assign(tx);
379 if (!list_empty(&chan->pending_list)) {
380 desc = list_last_entry(&chan->pending_list,
381 struct zynqmp_dma_desc_sw, node);
382 if (!list_empty(&desc->tx_list))
383 desc = list_last_entry(&desc->tx_list,
384 struct zynqmp_dma_desc_sw, node);
385 desc->src_v->nxtdscraddr = new->src_p;
386 desc->src_v->ctrl &= ~ZYNQMP_DMA_DESC_CTRL_STOP;
387 desc->dst_v->nxtdscraddr = new->dst_p;
388 desc->dst_v->ctrl &= ~ZYNQMP_DMA_DESC_CTRL_STOP;
391 list_add_tail(&new->node, &chan->pending_list);
392 spin_unlock_bh(&chan->lock);
394 return cookie;
398 * zynqmp_dma_get_descriptor - Get the sw descriptor from the pool
399 * @chan: ZynqMP DMA channel pointer
401 * Return: The sw descriptor
403 static struct zynqmp_dma_desc_sw *
404 zynqmp_dma_get_descriptor(struct zynqmp_dma_chan *chan)
406 struct zynqmp_dma_desc_sw *desc;
408 spin_lock_bh(&chan->lock);
409 desc = list_first_entry(&chan->free_list,
410 struct zynqmp_dma_desc_sw, node);
411 list_del(&desc->node);
412 spin_unlock_bh(&chan->lock);
414 INIT_LIST_HEAD(&desc->tx_list);
415 /* Clear the src and dst descriptor memory */
416 memset((void *)desc->src_v, 0, ZYNQMP_DMA_DESC_SIZE(chan));
417 memset((void *)desc->dst_v, 0, ZYNQMP_DMA_DESC_SIZE(chan));
419 return desc;
423 * zynqmp_dma_free_descriptor - Issue pending transactions
424 * @chan: ZynqMP DMA channel pointer
425 * @sdesc: Transaction descriptor pointer
427 static void zynqmp_dma_free_descriptor(struct zynqmp_dma_chan *chan,
428 struct zynqmp_dma_desc_sw *sdesc)
430 struct zynqmp_dma_desc_sw *child, *next;
432 chan->desc_free_cnt++;
433 list_add_tail(&sdesc->node, &chan->free_list);
434 list_for_each_entry_safe(child, next, &sdesc->tx_list, node) {
435 chan->desc_free_cnt++;
436 list_move_tail(&child->node, &chan->free_list);
441 * zynqmp_dma_free_desc_list - Free descriptors list
442 * @chan: ZynqMP DMA channel pointer
443 * @list: List to parse and delete the descriptor
445 static void zynqmp_dma_free_desc_list(struct zynqmp_dma_chan *chan,
446 struct list_head *list)
448 struct zynqmp_dma_desc_sw *desc, *next;
450 list_for_each_entry_safe(desc, next, list, node)
451 zynqmp_dma_free_descriptor(chan, desc);
455 * zynqmp_dma_alloc_chan_resources - Allocate channel resources
456 * @dchan: DMA channel
458 * Return: Number of descriptors on success and failure value on error
460 static int zynqmp_dma_alloc_chan_resources(struct dma_chan *dchan)
462 struct zynqmp_dma_chan *chan = to_chan(dchan);
463 struct zynqmp_dma_desc_sw *desc;
464 int i;
466 chan->sw_desc_pool = kzalloc(sizeof(*desc) * ZYNQMP_DMA_NUM_DESCS,
467 GFP_KERNEL);
468 if (!chan->sw_desc_pool)
469 return -ENOMEM;
471 chan->idle = true;
472 chan->desc_free_cnt = ZYNQMP_DMA_NUM_DESCS;
474 INIT_LIST_HEAD(&chan->free_list);
476 for (i = 0; i < ZYNQMP_DMA_NUM_DESCS; i++) {
477 desc = chan->sw_desc_pool + i;
478 dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
479 desc->async_tx.tx_submit = zynqmp_dma_tx_submit;
480 list_add_tail(&desc->node, &chan->free_list);
483 chan->desc_pool_v = dma_zalloc_coherent(chan->dev,
484 (2 * chan->desc_size * ZYNQMP_DMA_NUM_DESCS),
485 &chan->desc_pool_p, GFP_KERNEL);
486 if (!chan->desc_pool_v)
487 return -ENOMEM;
489 for (i = 0; i < ZYNQMP_DMA_NUM_DESCS; i++) {
490 desc = chan->sw_desc_pool + i;
491 desc->src_v = (struct zynqmp_dma_desc_ll *) (chan->desc_pool_v +
492 (i * ZYNQMP_DMA_DESC_SIZE(chan) * 2));
493 desc->dst_v = (struct zynqmp_dma_desc_ll *) (desc->src_v + 1);
494 desc->src_p = chan->desc_pool_p +
495 (i * ZYNQMP_DMA_DESC_SIZE(chan) * 2);
496 desc->dst_p = desc->src_p + ZYNQMP_DMA_DESC_SIZE(chan);
499 return ZYNQMP_DMA_NUM_DESCS;
503 * zynqmp_dma_start - Start DMA channel
504 * @chan: ZynqMP DMA channel pointer
506 static void zynqmp_dma_start(struct zynqmp_dma_chan *chan)
508 writel(ZYNQMP_DMA_INT_EN_DEFAULT_MASK, chan->regs + ZYNQMP_DMA_IER);
509 chan->idle = false;
510 writel(ZYNQMP_DMA_ENABLE, chan->regs + ZYNQMP_DMA_CTRL2);
514 * zynqmp_dma_handle_ovfl_int - Process the overflow interrupt
515 * @chan: ZynqMP DMA channel pointer
516 * @status: Interrupt status value
518 static void zynqmp_dma_handle_ovfl_int(struct zynqmp_dma_chan *chan, u32 status)
520 u32 val;
522 if (status & ZYNQMP_DMA_IRQ_DST_ACCT_ERR)
523 val = readl(chan->regs + ZYNQMP_DMA_IRQ_DST_ACCT);
524 if (status & ZYNQMP_DMA_IRQ_SRC_ACCT_ERR)
525 val = readl(chan->regs + ZYNQMP_DMA_IRQ_SRC_ACCT);
528 static void zynqmp_dma_config(struct zynqmp_dma_chan *chan)
530 u32 val;
532 val = readl(chan->regs + ZYNQMP_DMA_CTRL0);
533 val |= ZYNQMP_DMA_POINT_TYPE_SG;
534 writel(val, chan->regs + ZYNQMP_DMA_CTRL0);
536 val = readl(chan->regs + ZYNQMP_DMA_DATA_ATTR);
537 val = (val & ~ZYNQMP_DMA_ARLEN) |
538 (chan->src_burst_len << ZYNQMP_DMA_ARLEN_OFST);
539 val = (val & ~ZYNQMP_DMA_AWLEN) |
540 (chan->dst_burst_len << ZYNQMP_DMA_AWLEN_OFST);
541 writel(val, chan->regs + ZYNQMP_DMA_DATA_ATTR);
545 * zynqmp_dma_device_config - Zynqmp dma device configuration
546 * @dchan: DMA channel
547 * @config: DMA device config
549 static int zynqmp_dma_device_config(struct dma_chan *dchan,
550 struct dma_slave_config *config)
552 struct zynqmp_dma_chan *chan = to_chan(dchan);
554 chan->src_burst_len = config->src_maxburst;
555 chan->dst_burst_len = config->dst_maxburst;
557 return 0;
561 * zynqmp_dma_start_transfer - Initiate the new transfer
562 * @chan: ZynqMP DMA channel pointer
564 static void zynqmp_dma_start_transfer(struct zynqmp_dma_chan *chan)
566 struct zynqmp_dma_desc_sw *desc;
568 if (!chan->idle)
569 return;
571 zynqmp_dma_config(chan);
573 desc = list_first_entry_or_null(&chan->pending_list,
574 struct zynqmp_dma_desc_sw, node);
575 if (!desc)
576 return;
578 list_splice_tail_init(&chan->pending_list, &chan->active_list);
579 zynqmp_dma_update_desc_to_ctrlr(chan, desc);
580 zynqmp_dma_start(chan);
585 * zynqmp_dma_chan_desc_cleanup - Cleanup the completed descriptors
586 * @chan: ZynqMP DMA channel
588 static void zynqmp_dma_chan_desc_cleanup(struct zynqmp_dma_chan *chan)
590 struct zynqmp_dma_desc_sw *desc, *next;
592 list_for_each_entry_safe(desc, next, &chan->done_list, node) {
593 dma_async_tx_callback callback;
594 void *callback_param;
596 list_del(&desc->node);
598 callback = desc->async_tx.callback;
599 callback_param = desc->async_tx.callback_param;
600 if (callback) {
601 spin_unlock(&chan->lock);
602 callback(callback_param);
603 spin_lock(&chan->lock);
606 /* Run any dependencies, then free the descriptor */
607 zynqmp_dma_free_descriptor(chan, desc);
612 * zynqmp_dma_complete_descriptor - Mark the active descriptor as complete
613 * @chan: ZynqMP DMA channel pointer
615 static void zynqmp_dma_complete_descriptor(struct zynqmp_dma_chan *chan)
617 struct zynqmp_dma_desc_sw *desc;
619 desc = list_first_entry_or_null(&chan->active_list,
620 struct zynqmp_dma_desc_sw, node);
621 if (!desc)
622 return;
623 list_del(&desc->node);
624 dma_cookie_complete(&desc->async_tx);
625 list_add_tail(&desc->node, &chan->done_list);
629 * zynqmp_dma_issue_pending - Issue pending transactions
630 * @dchan: DMA channel pointer
632 static void zynqmp_dma_issue_pending(struct dma_chan *dchan)
634 struct zynqmp_dma_chan *chan = to_chan(dchan);
636 spin_lock_bh(&chan->lock);
637 zynqmp_dma_start_transfer(chan);
638 spin_unlock_bh(&chan->lock);
642 * zynqmp_dma_free_descriptors - Free channel descriptors
643 * @dchan: DMA channel pointer
645 static void zynqmp_dma_free_descriptors(struct zynqmp_dma_chan *chan)
647 zynqmp_dma_free_desc_list(chan, &chan->active_list);
648 zynqmp_dma_free_desc_list(chan, &chan->pending_list);
649 zynqmp_dma_free_desc_list(chan, &chan->done_list);
653 * zynqmp_dma_free_chan_resources - Free channel resources
654 * @dchan: DMA channel pointer
656 static void zynqmp_dma_free_chan_resources(struct dma_chan *dchan)
658 struct zynqmp_dma_chan *chan = to_chan(dchan);
660 spin_lock_bh(&chan->lock);
661 zynqmp_dma_free_descriptors(chan);
662 spin_unlock_bh(&chan->lock);
663 dma_free_coherent(chan->dev,
664 (2 * ZYNQMP_DMA_DESC_SIZE(chan) * ZYNQMP_DMA_NUM_DESCS),
665 chan->desc_pool_v, chan->desc_pool_p);
666 kfree(chan->sw_desc_pool);
670 * zynqmp_dma_reset - Reset the channel
671 * @chan: ZynqMP DMA channel pointer
673 static void zynqmp_dma_reset(struct zynqmp_dma_chan *chan)
675 writel(ZYNQMP_DMA_IDS_DEFAULT_MASK, chan->regs + ZYNQMP_DMA_IDS);
677 zynqmp_dma_complete_descriptor(chan);
678 zynqmp_dma_chan_desc_cleanup(chan);
679 zynqmp_dma_free_descriptors(chan);
680 zynqmp_dma_init(chan);
684 * zynqmp_dma_irq_handler - ZynqMP DMA Interrupt handler
685 * @irq: IRQ number
686 * @data: Pointer to the ZynqMP DMA channel structure
688 * Return: IRQ_HANDLED/IRQ_NONE
690 static irqreturn_t zynqmp_dma_irq_handler(int irq, void *data)
692 struct zynqmp_dma_chan *chan = (struct zynqmp_dma_chan *)data;
693 u32 isr, imr, status;
694 irqreturn_t ret = IRQ_NONE;
696 isr = readl(chan->regs + ZYNQMP_DMA_ISR);
697 imr = readl(chan->regs + ZYNQMP_DMA_IMR);
698 status = isr & ~imr;
700 writel(isr, chan->regs + ZYNQMP_DMA_ISR);
701 if (status & ZYNQMP_DMA_INT_DONE) {
702 tasklet_schedule(&chan->tasklet);
703 ret = IRQ_HANDLED;
706 if (status & ZYNQMP_DMA_DONE)
707 chan->idle = true;
709 if (status & ZYNQMP_DMA_INT_ERR) {
710 chan->err = true;
711 tasklet_schedule(&chan->tasklet);
712 dev_err(chan->dev, "Channel %p has errors\n", chan);
713 ret = IRQ_HANDLED;
716 if (status & ZYNQMP_DMA_INT_OVRFL) {
717 zynqmp_dma_handle_ovfl_int(chan, status);
718 dev_info(chan->dev, "Channel %p overflow interrupt\n", chan);
719 ret = IRQ_HANDLED;
722 return ret;
726 * zynqmp_dma_do_tasklet - Schedule completion tasklet
727 * @data: Pointer to the ZynqMP DMA channel structure
729 static void zynqmp_dma_do_tasklet(unsigned long data)
731 struct zynqmp_dma_chan *chan = (struct zynqmp_dma_chan *)data;
732 u32 count;
734 spin_lock(&chan->lock);
736 if (chan->err) {
737 zynqmp_dma_reset(chan);
738 chan->err = false;
739 goto unlock;
742 count = readl(chan->regs + ZYNQMP_DMA_IRQ_DST_ACCT);
744 while (count) {
745 zynqmp_dma_complete_descriptor(chan);
746 zynqmp_dma_chan_desc_cleanup(chan);
747 count--;
750 if (chan->idle)
751 zynqmp_dma_start_transfer(chan);
753 unlock:
754 spin_unlock(&chan->lock);
758 * zynqmp_dma_device_terminate_all - Aborts all transfers on a channel
759 * @dchan: DMA channel pointer
761 * Return: Always '0'
763 static int zynqmp_dma_device_terminate_all(struct dma_chan *dchan)
765 struct zynqmp_dma_chan *chan = to_chan(dchan);
767 spin_lock_bh(&chan->lock);
768 writel(ZYNQMP_DMA_IDS_DEFAULT_MASK, chan->regs + ZYNQMP_DMA_IDS);
769 zynqmp_dma_free_descriptors(chan);
770 spin_unlock_bh(&chan->lock);
772 return 0;
776 * zynqmp_dma_prep_memcpy - prepare descriptors for memcpy transaction
777 * @dchan: DMA channel
778 * @dma_dst: Destination buffer address
779 * @dma_src: Source buffer address
780 * @len: Transfer length
781 * @flags: transfer ack flags
783 * Return: Async transaction descriptor on success and NULL on failure
785 static struct dma_async_tx_descriptor *zynqmp_dma_prep_memcpy(
786 struct dma_chan *dchan, dma_addr_t dma_dst,
787 dma_addr_t dma_src, size_t len, ulong flags)
789 struct zynqmp_dma_chan *chan;
790 struct zynqmp_dma_desc_sw *new, *first = NULL;
791 void *desc = NULL, *prev = NULL;
792 size_t copy;
793 u32 desc_cnt;
795 chan = to_chan(dchan);
797 if (len > ZYNQMP_DMA_MAX_TRANS_LEN)
798 return NULL;
800 desc_cnt = DIV_ROUND_UP(len, ZYNQMP_DMA_MAX_TRANS_LEN);
802 spin_lock_bh(&chan->lock);
803 if (desc_cnt > chan->desc_free_cnt) {
804 spin_unlock_bh(&chan->lock);
805 dev_dbg(chan->dev, "chan %p descs are not available\n", chan);
806 return NULL;
808 chan->desc_free_cnt = chan->desc_free_cnt - desc_cnt;
809 spin_unlock_bh(&chan->lock);
811 do {
812 /* Allocate and populate the descriptor */
813 new = zynqmp_dma_get_descriptor(chan);
815 copy = min_t(size_t, len, ZYNQMP_DMA_MAX_TRANS_LEN);
816 desc = (struct zynqmp_dma_desc_ll *)new->src_v;
817 zynqmp_dma_config_sg_ll_desc(chan, desc, dma_src,
818 dma_dst, copy, prev);
819 prev = desc;
820 len -= copy;
821 dma_src += copy;
822 dma_dst += copy;
823 if (!first)
824 first = new;
825 else
826 list_add_tail(&new->node, &first->tx_list);
827 } while (len);
829 zynqmp_dma_desc_config_eod(chan, desc);
830 async_tx_ack(&first->async_tx);
831 first->async_tx.flags = flags;
832 return &first->async_tx;
836 * zynqmp_dma_prep_slave_sg - prepare descriptors for a memory sg transaction
837 * @dchan: DMA channel
838 * @dst_sg: Destination scatter list
839 * @dst_sg_len: Number of entries in destination scatter list
840 * @src_sg: Source scatter list
841 * @src_sg_len: Number of entries in source scatter list
842 * @flags: transfer ack flags
844 * Return: Async transaction descriptor on success and NULL on failure
846 static struct dma_async_tx_descriptor *zynqmp_dma_prep_sg(
847 struct dma_chan *dchan, struct scatterlist *dst_sg,
848 unsigned int dst_sg_len, struct scatterlist *src_sg,
849 unsigned int src_sg_len, unsigned long flags)
851 struct zynqmp_dma_desc_sw *new, *first = NULL;
852 struct zynqmp_dma_chan *chan = to_chan(dchan);
853 void *desc = NULL, *prev = NULL;
854 size_t len, dst_avail, src_avail;
855 dma_addr_t dma_dst, dma_src;
856 u32 desc_cnt = 0, i;
857 struct scatterlist *sg;
859 for_each_sg(src_sg, sg, src_sg_len, i)
860 desc_cnt += DIV_ROUND_UP(sg_dma_len(sg),
861 ZYNQMP_DMA_MAX_TRANS_LEN);
863 spin_lock_bh(&chan->lock);
864 if (desc_cnt > chan->desc_free_cnt) {
865 spin_unlock_bh(&chan->lock);
866 dev_dbg(chan->dev, "chan %p descs are not available\n", chan);
867 return NULL;
869 chan->desc_free_cnt = chan->desc_free_cnt - desc_cnt;
870 spin_unlock_bh(&chan->lock);
872 dst_avail = sg_dma_len(dst_sg);
873 src_avail = sg_dma_len(src_sg);
875 /* Run until we are out of scatterlist entries */
876 while (true) {
877 /* Allocate and populate the descriptor */
878 new = zynqmp_dma_get_descriptor(chan);
879 desc = (struct zynqmp_dma_desc_ll *)new->src_v;
880 len = min_t(size_t, src_avail, dst_avail);
881 len = min_t(size_t, len, ZYNQMP_DMA_MAX_TRANS_LEN);
882 if (len == 0)
883 goto fetch;
884 dma_dst = sg_dma_address(dst_sg) + sg_dma_len(dst_sg) -
885 dst_avail;
886 dma_src = sg_dma_address(src_sg) + sg_dma_len(src_sg) -
887 src_avail;
889 zynqmp_dma_config_sg_ll_desc(chan, desc, dma_src, dma_dst,
890 len, prev);
891 prev = desc;
892 dst_avail -= len;
893 src_avail -= len;
895 if (!first)
896 first = new;
897 else
898 list_add_tail(&new->node, &first->tx_list);
899 fetch:
900 /* Fetch the next dst scatterlist entry */
901 if (dst_avail == 0) {
902 if (dst_sg_len == 0)
903 break;
904 dst_sg = sg_next(dst_sg);
905 if (dst_sg == NULL)
906 break;
907 dst_sg_len--;
908 dst_avail = sg_dma_len(dst_sg);
910 /* Fetch the next src scatterlist entry */
911 if (src_avail == 0) {
912 if (src_sg_len == 0)
913 break;
914 src_sg = sg_next(src_sg);
915 if (src_sg == NULL)
916 break;
917 src_sg_len--;
918 src_avail = sg_dma_len(src_sg);
922 zynqmp_dma_desc_config_eod(chan, desc);
923 first->async_tx.flags = flags;
924 return &first->async_tx;
928 * zynqmp_dma_chan_remove - Channel remove function
929 * @chan: ZynqMP DMA channel pointer
931 static void zynqmp_dma_chan_remove(struct zynqmp_dma_chan *chan)
933 if (!chan)
934 return;
936 devm_free_irq(chan->zdev->dev, chan->irq, chan);
937 tasklet_kill(&chan->tasklet);
938 list_del(&chan->common.device_node);
939 clk_disable_unprepare(chan->clk_apb);
940 clk_disable_unprepare(chan->clk_main);
944 * zynqmp_dma_chan_probe - Per Channel Probing
945 * @zdev: Driver specific device structure
946 * @pdev: Pointer to the platform_device structure
948 * Return: '0' on success and failure value on error
950 static int zynqmp_dma_chan_probe(struct zynqmp_dma_device *zdev,
951 struct platform_device *pdev)
953 struct zynqmp_dma_chan *chan;
954 struct resource *res;
955 struct device_node *node = pdev->dev.of_node;
956 int err;
958 chan = devm_kzalloc(zdev->dev, sizeof(*chan), GFP_KERNEL);
959 if (!chan)
960 return -ENOMEM;
961 chan->dev = zdev->dev;
962 chan->zdev = zdev;
964 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
965 chan->regs = devm_ioremap_resource(&pdev->dev, res);
966 if (IS_ERR(chan->regs))
967 return PTR_ERR(chan->regs);
969 chan->bus_width = ZYNQMP_DMA_BUS_WIDTH_64;
970 chan->dst_burst_len = ZYNQMP_DMA_AWLEN_RST_VAL;
971 chan->src_burst_len = ZYNQMP_DMA_ARLEN_RST_VAL;
972 err = of_property_read_u32(node, "xlnx,bus-width", &chan->bus_width);
973 if (err < 0) {
974 dev_err(&pdev->dev, "missing xlnx,bus-width property\n");
975 return err;
978 if (chan->bus_width != ZYNQMP_DMA_BUS_WIDTH_64 &&
979 chan->bus_width != ZYNQMP_DMA_BUS_WIDTH_128) {
980 dev_err(zdev->dev, "invalid bus-width value");
981 return -EINVAL;
984 chan->is_dmacoherent = of_property_read_bool(node, "dma-coherent");
985 zdev->chan = chan;
986 tasklet_init(&chan->tasklet, zynqmp_dma_do_tasklet, (ulong)chan);
987 spin_lock_init(&chan->lock);
988 INIT_LIST_HEAD(&chan->active_list);
989 INIT_LIST_HEAD(&chan->pending_list);
990 INIT_LIST_HEAD(&chan->done_list);
991 INIT_LIST_HEAD(&chan->free_list);
993 dma_cookie_init(&chan->common);
994 chan->common.device = &zdev->common;
995 list_add_tail(&chan->common.device_node, &zdev->common.channels);
997 zynqmp_dma_init(chan);
998 chan->irq = platform_get_irq(pdev, 0);
999 if (chan->irq < 0)
1000 return -ENXIO;
1001 err = devm_request_irq(&pdev->dev, chan->irq, zynqmp_dma_irq_handler, 0,
1002 "zynqmp-dma", chan);
1003 if (err)
1004 return err;
1005 chan->clk_main = devm_clk_get(&pdev->dev, "clk_main");
1006 if (IS_ERR(chan->clk_main)) {
1007 dev_err(&pdev->dev, "main clock not found.\n");
1008 return PTR_ERR(chan->clk_main);
1011 chan->clk_apb = devm_clk_get(&pdev->dev, "clk_apb");
1012 if (IS_ERR(chan->clk_apb)) {
1013 dev_err(&pdev->dev, "apb clock not found.\n");
1014 return PTR_ERR(chan->clk_apb);
1017 err = clk_prepare_enable(chan->clk_main);
1018 if (err) {
1019 dev_err(&pdev->dev, "Unable to enable main clock.\n");
1020 return err;
1023 err = clk_prepare_enable(chan->clk_apb);
1024 if (err) {
1025 clk_disable_unprepare(chan->clk_main);
1026 dev_err(&pdev->dev, "Unable to enable apb clock.\n");
1027 return err;
1030 chan->desc_size = sizeof(struct zynqmp_dma_desc_ll);
1031 chan->idle = true;
1032 return 0;
1036 * of_zynqmp_dma_xlate - Translation function
1037 * @dma_spec: Pointer to DMA specifier as found in the device tree
1038 * @ofdma: Pointer to DMA controller data
1040 * Return: DMA channel pointer on success and NULL on error
1042 static struct dma_chan *of_zynqmp_dma_xlate(struct of_phandle_args *dma_spec,
1043 struct of_dma *ofdma)
1045 struct zynqmp_dma_device *zdev = ofdma->of_dma_data;
1047 return dma_get_slave_channel(&zdev->chan->common);
1051 * zynqmp_dma_probe - Driver probe function
1052 * @pdev: Pointer to the platform_device structure
1054 * Return: '0' on success and failure value on error
1056 static int zynqmp_dma_probe(struct platform_device *pdev)
1058 struct zynqmp_dma_device *zdev;
1059 struct dma_device *p;
1060 int ret;
1062 zdev = devm_kzalloc(&pdev->dev, sizeof(*zdev), GFP_KERNEL);
1063 if (!zdev)
1064 return -ENOMEM;
1066 zdev->dev = &pdev->dev;
1067 INIT_LIST_HEAD(&zdev->common.channels);
1069 dma_set_mask(&pdev->dev, DMA_BIT_MASK(44));
1070 dma_cap_set(DMA_SG, zdev->common.cap_mask);
1071 dma_cap_set(DMA_MEMCPY, zdev->common.cap_mask);
1073 p = &zdev->common;
1074 p->device_prep_dma_sg = zynqmp_dma_prep_sg;
1075 p->device_prep_dma_memcpy = zynqmp_dma_prep_memcpy;
1076 p->device_terminate_all = zynqmp_dma_device_terminate_all;
1077 p->device_issue_pending = zynqmp_dma_issue_pending;
1078 p->device_alloc_chan_resources = zynqmp_dma_alloc_chan_resources;
1079 p->device_free_chan_resources = zynqmp_dma_free_chan_resources;
1080 p->device_tx_status = dma_cookie_status;
1081 p->device_config = zynqmp_dma_device_config;
1082 p->dev = &pdev->dev;
1084 platform_set_drvdata(pdev, zdev);
1086 ret = zynqmp_dma_chan_probe(zdev, pdev);
1087 if (ret) {
1088 dev_err(&pdev->dev, "Probing channel failed\n");
1089 goto free_chan_resources;
1092 p->dst_addr_widths = BIT(zdev->chan->bus_width / 8);
1093 p->src_addr_widths = BIT(zdev->chan->bus_width / 8);
1095 dma_async_device_register(&zdev->common);
1097 ret = of_dma_controller_register(pdev->dev.of_node,
1098 of_zynqmp_dma_xlate, zdev);
1099 if (ret) {
1100 dev_err(&pdev->dev, "Unable to register DMA to DT\n");
1101 dma_async_device_unregister(&zdev->common);
1102 goto free_chan_resources;
1105 dev_info(&pdev->dev, "ZynqMP DMA driver Probe success\n");
1107 return 0;
1109 free_chan_resources:
1110 zynqmp_dma_chan_remove(zdev->chan);
1111 return ret;
1115 * zynqmp_dma_remove - Driver remove function
1116 * @pdev: Pointer to the platform_device structure
1118 * Return: Always '0'
1120 static int zynqmp_dma_remove(struct platform_device *pdev)
1122 struct zynqmp_dma_device *zdev = platform_get_drvdata(pdev);
1124 of_dma_controller_free(pdev->dev.of_node);
1125 dma_async_device_unregister(&zdev->common);
1127 zynqmp_dma_chan_remove(zdev->chan);
1129 return 0;
1132 static const struct of_device_id zynqmp_dma_of_match[] = {
1133 { .compatible = "xlnx,zynqmp-dma-1.0", },
1136 MODULE_DEVICE_TABLE(of, zynqmp_dma_of_match);
1138 static struct platform_driver zynqmp_dma_driver = {
1139 .driver = {
1140 .name = "xilinx-zynqmp-dma",
1141 .of_match_table = zynqmp_dma_of_match,
1143 .probe = zynqmp_dma_probe,
1144 .remove = zynqmp_dma_remove,
1147 module_platform_driver(zynqmp_dma_driver);
1149 MODULE_LICENSE("GPL");
1150 MODULE_AUTHOR("Xilinx, Inc.");
1151 MODULE_DESCRIPTION("Xilinx ZynqMP DMA driver");