2 * Copyright (C) Freescale Semicondutor, Inc. 2007, 2008.
3 * Copyright (C) Semihalf 2009
4 * Copyright (C) Ilya Yanok, Emcraft Systems 2010
5 * Copyright (C) Alexander Popov, Promcontroller 2014
7 * Written by Piotr Ziecik <kosmo@semihalf.com>. Hardware description
8 * (defines, structures and comments) was taken from MPC5121 DMA driver
9 * written by Hongjun Chen <hong-jun.chen@freescale.com>.
11 * Approved as OSADL project by a majority of OSADL members and funded
12 * by OSADL membership fees in 2009; for details see www.osadl.org.
14 * This program is free software; you can redistribute it and/or modify it
15 * under the terms of the GNU General Public License as published by the Free
16 * Software Foundation; either version 2 of the License, or (at your option)
19 * This program is distributed in the hope that it will be useful, but WITHOUT
20 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
21 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
24 * You should have received a copy of the GNU General Public License along with
25 * this program; if not, write to the Free Software Foundation, Inc., 59
26 * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
28 * The full GNU General Public License is included in this distribution in the
29 * file called COPYING.
33 * MPC512x and MPC8308 DMA driver. It supports
34 * memory to memory data transfers (tested using dmatest module) and
35 * data transfers between memory and peripheral I/O memory
36 * by means of slave scatter/gather with these limitations:
37 * - chunked transfers (described by s/g lists with more than one item)
38 * are refused as long as proper support for scatter/gather is missing;
39 * - transfers on MPC8308 always start from software as this SoC appears
40 * not to have external request lines for peripheral flow control;
41 * - only peripheral devices with 4-byte FIFO access register are supported;
42 * - minimal memory <-> I/O memory transfer chunk is 4 bytes and consequently
43 * source and destination addresses must be 4-byte aligned
44 * and transfer size must be aligned on (4 * maxburst) boundary;
47 #include <linux/module.h>
48 #include <linux/dmaengine.h>
49 #include <linux/dma-mapping.h>
50 #include <linux/interrupt.h>
52 #include <linux/slab.h>
53 #include <linux/of_address.h>
54 #include <linux/of_device.h>
55 #include <linux/of_irq.h>
56 #include <linux/of_dma.h>
57 #include <linux/of_platform.h>
59 #include <linux/random.h>
61 #include "dmaengine.h"
63 /* Number of DMA Transfer descriptors allocated per channel */
64 #define MPC_DMA_DESCRIPTORS 64
66 /* Macro definitions */
67 #define MPC_DMA_TCD_OFFSET 0x1000
70 * Maximum channel counts for individual hardware variants
71 * and the maximum channel count over all supported controllers,
72 * used for data structure size
74 #define MPC8308_DMACHAN_MAX 16
75 #define MPC512x_DMACHAN_MAX 64
76 #define MPC_DMA_CHANNELS 64
78 /* Arbitration mode of group and channel */
79 #define MPC_DMA_DMACR_EDCG (1 << 31)
80 #define MPC_DMA_DMACR_ERGA (1 << 3)
81 #define MPC_DMA_DMACR_ERCA (1 << 2)
84 #define MPC_DMA_DMAES_VLD (1 << 31)
85 #define MPC_DMA_DMAES_GPE (1 << 15)
86 #define MPC_DMA_DMAES_CPE (1 << 14)
87 #define MPC_DMA_DMAES_ERRCHN(err) \
89 #define MPC_DMA_DMAES_SAE (1 << 7)
90 #define MPC_DMA_DMAES_SOE (1 << 6)
91 #define MPC_DMA_DMAES_DAE (1 << 5)
92 #define MPC_DMA_DMAES_DOE (1 << 4)
93 #define MPC_DMA_DMAES_NCE (1 << 3)
94 #define MPC_DMA_DMAES_SGE (1 << 2)
95 #define MPC_DMA_DMAES_SBE (1 << 1)
96 #define MPC_DMA_DMAES_DBE (1 << 0)
98 #define MPC_DMA_DMAGPOR_SNOOP_ENABLE (1 << 6)
100 #define MPC_DMA_TSIZE_1 0x00
101 #define MPC_DMA_TSIZE_2 0x01
102 #define MPC_DMA_TSIZE_4 0x02
103 #define MPC_DMA_TSIZE_16 0x04
104 #define MPC_DMA_TSIZE_32 0x05
106 /* MPC5121 DMA engine registers */
107 struct __attribute__ ((__packed__
)) mpc_dma_regs
{
109 u32 dmacr
; /* DMA control register */
110 u32 dmaes
; /* DMA error status */
112 u32 dmaerqh
; /* DMA enable request high(channels 63~32) */
113 u32 dmaerql
; /* DMA enable request low(channels 31~0) */
114 u32 dmaeeih
; /* DMA enable error interrupt high(ch63~32) */
115 u32 dmaeeil
; /* DMA enable error interrupt low(ch31~0) */
117 u8 dmaserq
; /* DMA set enable request */
118 u8 dmacerq
; /* DMA clear enable request */
119 u8 dmaseei
; /* DMA set enable error interrupt */
120 u8 dmaceei
; /* DMA clear enable error interrupt */
122 u8 dmacint
; /* DMA clear interrupt request */
123 u8 dmacerr
; /* DMA clear error */
124 u8 dmassrt
; /* DMA set start bit */
125 u8 dmacdne
; /* DMA clear DONE status bit */
127 u32 dmainth
; /* DMA interrupt request high(ch63~32) */
128 u32 dmaintl
; /* DMA interrupt request low(ch31~0) */
129 u32 dmaerrh
; /* DMA error high(ch63~32) */
130 u32 dmaerrl
; /* DMA error low(ch31~0) */
132 u32 dmahrsh
; /* DMA hw request status high(ch63~32) */
133 u32 dmahrsl
; /* DMA hardware request status low(ch31~0) */
135 u32 dmaihsa
; /* DMA interrupt high select AXE(ch63~32) */
136 u32 dmagpor
; /* (General purpose register on MPC8308) */
138 u32 dmailsa
; /* DMA interrupt low select AXE(ch31~0) */
140 u32 reserve0
[48]; /* Reserved */
142 u8 dchpri
[MPC_DMA_CHANNELS
];
143 /* DMA channels(0~63) priority */
146 struct __attribute__ ((__packed__
)) mpc_dma_tcd
{
148 u32 saddr
; /* Source address */
150 u32 smod
:5; /* Source address modulo */
151 u32 ssize
:3; /* Source data transfer size */
152 u32 dmod
:5; /* Destination address modulo */
153 u32 dsize
:3; /* Destination data transfer size */
154 u32 soff
:16; /* Signed source address offset */
157 u32 nbytes
; /* Inner "minor" byte count */
158 u32 slast
; /* Last source address adjustment */
159 u32 daddr
; /* Destination address */
162 u32 citer_elink
:1; /* Enable channel-to-channel linking on
163 * minor loop complete
165 u32 citer_linkch
:6; /* Link channel for minor loop complete */
166 u32 citer
:9; /* Current "major" iteration count */
167 u32 doff
:16; /* Signed destination address offset */
170 u32 dlast_sga
; /* Last Destination address adjustment/scatter
175 u32 biter_elink
:1; /* Enable channel-to-channel linking on major
179 u32 biter
:9; /* Beginning "major" iteration count */
180 u32 bwc
:2; /* Bandwidth control */
181 u32 major_linkch
:6; /* Link channel number */
182 u32 done
:1; /* Channel done */
183 u32 active
:1; /* Channel active */
184 u32 major_elink
:1; /* Enable channel-to-channel linking on major
187 u32 e_sg
:1; /* Enable scatter/gather processing */
188 u32 d_req
:1; /* Disable request */
189 u32 int_half
:1; /* Enable an interrupt when major counter is
192 u32 int_maj
:1; /* Enable an interrupt when major iteration
195 u32 start
:1; /* Channel start */
198 struct mpc_dma_desc
{
199 struct dma_async_tx_descriptor desc
;
200 struct mpc_dma_tcd
*tcd
;
201 dma_addr_t tcd_paddr
;
203 struct list_head node
;
204 int will_access_peripheral
;
207 struct mpc_dma_chan
{
208 struct dma_chan chan
;
209 struct list_head free
;
210 struct list_head prepared
;
211 struct list_head queued
;
212 struct list_head active
;
213 struct list_head completed
;
214 struct mpc_dma_tcd
*tcd
;
215 dma_addr_t tcd_paddr
;
217 /* Settings for access to peripheral FIFO */
218 dma_addr_t src_per_paddr
;
220 dma_addr_t dst_per_paddr
;
223 /* Lock for this structure */
228 struct dma_device dma
;
229 struct tasklet_struct tasklet
;
230 struct mpc_dma_chan channels
[MPC_DMA_CHANNELS
];
231 struct mpc_dma_regs __iomem
*regs
;
232 struct mpc_dma_tcd __iomem
*tcd
;
238 /* Lock for error_status field in this structure */
239 spinlock_t error_status_lock
;
242 #define DRV_NAME "mpc512x_dma"
244 /* Convert struct dma_chan to struct mpc_dma_chan */
245 static inline struct mpc_dma_chan
*dma_chan_to_mpc_dma_chan(struct dma_chan
*c
)
247 return container_of(c
, struct mpc_dma_chan
, chan
);
250 /* Convert struct dma_chan to struct mpc_dma */
251 static inline struct mpc_dma
*dma_chan_to_mpc_dma(struct dma_chan
*c
)
253 struct mpc_dma_chan
*mchan
= dma_chan_to_mpc_dma_chan(c
);
254 return container_of(mchan
, struct mpc_dma
, channels
[c
->chan_id
]);
258 * Execute all queued DMA descriptors.
260 * Following requirements must be met while calling mpc_dma_execute():
261 * a) mchan->lock is acquired,
262 * b) mchan->active list is empty,
263 * c) mchan->queued list contains at least one entry.
265 static void mpc_dma_execute(struct mpc_dma_chan
*mchan
)
267 struct mpc_dma
*mdma
= dma_chan_to_mpc_dma(&mchan
->chan
);
268 struct mpc_dma_desc
*first
= NULL
;
269 struct mpc_dma_desc
*prev
= NULL
;
270 struct mpc_dma_desc
*mdesc
;
271 int cid
= mchan
->chan
.chan_id
;
273 while (!list_empty(&mchan
->queued
)) {
274 mdesc
= list_first_entry(&mchan
->queued
,
275 struct mpc_dma_desc
, node
);
277 * Grab either several mem-to-mem transfer descriptors
278 * or one peripheral transfer descriptor,
279 * don't mix mem-to-mem and peripheral transfer descriptors
280 * within the same 'active' list.
282 if (mdesc
->will_access_peripheral
) {
283 if (list_empty(&mchan
->active
))
284 list_move_tail(&mdesc
->node
, &mchan
->active
);
287 list_move_tail(&mdesc
->node
, &mchan
->active
);
291 /* Chain descriptors into one transaction */
292 list_for_each_entry(mdesc
, &mchan
->active
, node
) {
301 prev
->tcd
->dlast_sga
= mdesc
->tcd_paddr
;
303 mdesc
->tcd
->start
= 1;
308 prev
->tcd
->int_maj
= 1;
310 /* Send first descriptor in chain into hardware */
311 memcpy_toio(&mdma
->tcd
[cid
], first
->tcd
, sizeof(struct mpc_dma_tcd
));
314 mdma
->tcd
[cid
].e_sg
= 1;
316 if (mdma
->is_mpc8308
) {
317 /* MPC8308, no request lines, software initiated start */
318 out_8(&mdma
->regs
->dmassrt
, cid
);
319 } else if (first
->will_access_peripheral
) {
320 /* Peripherals involved, start by external request signal */
321 out_8(&mdma
->regs
->dmaserq
, cid
);
323 /* Memory to memory transfer, software initiated start */
324 out_8(&mdma
->regs
->dmassrt
, cid
);
328 /* Handle interrupt on one half of DMA controller (32 channels) */
329 static void mpc_dma_irq_process(struct mpc_dma
*mdma
, u32 is
, u32 es
, int off
)
331 struct mpc_dma_chan
*mchan
;
332 struct mpc_dma_desc
*mdesc
;
333 u32 status
= is
| es
;
336 while ((ch
= fls(status
) - 1) >= 0) {
337 status
&= ~(1 << ch
);
338 mchan
= &mdma
->channels
[ch
+ off
];
340 spin_lock(&mchan
->lock
);
342 out_8(&mdma
->regs
->dmacint
, ch
+ off
);
343 out_8(&mdma
->regs
->dmacerr
, ch
+ off
);
345 /* Check error status */
347 list_for_each_entry(mdesc
, &mchan
->active
, node
)
350 /* Execute queued descriptors */
351 list_splice_tail_init(&mchan
->active
, &mchan
->completed
);
352 if (!list_empty(&mchan
->queued
))
353 mpc_dma_execute(mchan
);
355 spin_unlock(&mchan
->lock
);
359 /* Interrupt handler */
360 static irqreturn_t
mpc_dma_irq(int irq
, void *data
)
362 struct mpc_dma
*mdma
= data
;
365 /* Save error status register */
366 es
= in_be32(&mdma
->regs
->dmaes
);
367 spin_lock(&mdma
->error_status_lock
);
368 if ((es
& MPC_DMA_DMAES_VLD
) && mdma
->error_status
== 0)
369 mdma
->error_status
= es
;
370 spin_unlock(&mdma
->error_status_lock
);
372 /* Handle interrupt on each channel */
373 if (mdma
->dma
.chancnt
> 32) {
374 mpc_dma_irq_process(mdma
, in_be32(&mdma
->regs
->dmainth
),
375 in_be32(&mdma
->regs
->dmaerrh
), 32);
377 mpc_dma_irq_process(mdma
, in_be32(&mdma
->regs
->dmaintl
),
378 in_be32(&mdma
->regs
->dmaerrl
), 0);
380 /* Schedule tasklet */
381 tasklet_schedule(&mdma
->tasklet
);
386 /* process completed descriptors */
387 static void mpc_dma_process_completed(struct mpc_dma
*mdma
)
389 dma_cookie_t last_cookie
= 0;
390 struct mpc_dma_chan
*mchan
;
391 struct mpc_dma_desc
*mdesc
;
392 struct dma_async_tx_descriptor
*desc
;
397 for (i
= 0; i
< mdma
->dma
.chancnt
; i
++) {
398 mchan
= &mdma
->channels
[i
];
400 /* Get all completed descriptors */
401 spin_lock_irqsave(&mchan
->lock
, flags
);
402 if (!list_empty(&mchan
->completed
))
403 list_splice_tail_init(&mchan
->completed
, &list
);
404 spin_unlock_irqrestore(&mchan
->lock
, flags
);
406 if (list_empty(&list
))
409 /* Execute callbacks and run dependencies */
410 list_for_each_entry(mdesc
, &list
, node
) {
414 desc
->callback(desc
->callback_param
);
416 last_cookie
= desc
->cookie
;
417 dma_run_dependencies(desc
);
420 /* Free descriptors */
421 spin_lock_irqsave(&mchan
->lock
, flags
);
422 list_splice_tail_init(&list
, &mchan
->free
);
423 mchan
->chan
.completed_cookie
= last_cookie
;
424 spin_unlock_irqrestore(&mchan
->lock
, flags
);
429 static void mpc_dma_tasklet(unsigned long data
)
431 struct mpc_dma
*mdma
= (void *)data
;
435 spin_lock_irqsave(&mdma
->error_status_lock
, flags
);
436 es
= mdma
->error_status
;
437 mdma
->error_status
= 0;
438 spin_unlock_irqrestore(&mdma
->error_status_lock
, flags
);
440 /* Print nice error report */
442 dev_err(mdma
->dma
.dev
,
443 "Hardware reported following error(s) on channel %u:\n",
444 MPC_DMA_DMAES_ERRCHN(es
));
446 if (es
& MPC_DMA_DMAES_GPE
)
447 dev_err(mdma
->dma
.dev
, "- Group Priority Error\n");
448 if (es
& MPC_DMA_DMAES_CPE
)
449 dev_err(mdma
->dma
.dev
, "- Channel Priority Error\n");
450 if (es
& MPC_DMA_DMAES_SAE
)
451 dev_err(mdma
->dma
.dev
, "- Source Address Error\n");
452 if (es
& MPC_DMA_DMAES_SOE
)
453 dev_err(mdma
->dma
.dev
, "- Source Offset"
454 " Configuration Error\n");
455 if (es
& MPC_DMA_DMAES_DAE
)
456 dev_err(mdma
->dma
.dev
, "- Destination Address"
458 if (es
& MPC_DMA_DMAES_DOE
)
459 dev_err(mdma
->dma
.dev
, "- Destination Offset"
460 " Configuration Error\n");
461 if (es
& MPC_DMA_DMAES_NCE
)
462 dev_err(mdma
->dma
.dev
, "- NBytes/Citter"
463 " Configuration Error\n");
464 if (es
& MPC_DMA_DMAES_SGE
)
465 dev_err(mdma
->dma
.dev
, "- Scatter/Gather"
466 " Configuration Error\n");
467 if (es
& MPC_DMA_DMAES_SBE
)
468 dev_err(mdma
->dma
.dev
, "- Source Bus Error\n");
469 if (es
& MPC_DMA_DMAES_DBE
)
470 dev_err(mdma
->dma
.dev
, "- Destination Bus Error\n");
473 mpc_dma_process_completed(mdma
);
476 /* Submit descriptor to hardware */
477 static dma_cookie_t
mpc_dma_tx_submit(struct dma_async_tx_descriptor
*txd
)
479 struct mpc_dma_chan
*mchan
= dma_chan_to_mpc_dma_chan(txd
->chan
);
480 struct mpc_dma_desc
*mdesc
;
484 mdesc
= container_of(txd
, struct mpc_dma_desc
, desc
);
486 spin_lock_irqsave(&mchan
->lock
, flags
);
488 /* Move descriptor to queue */
489 list_move_tail(&mdesc
->node
, &mchan
->queued
);
491 /* If channel is idle, execute all queued descriptors */
492 if (list_empty(&mchan
->active
))
493 mpc_dma_execute(mchan
);
496 cookie
= dma_cookie_assign(txd
);
497 spin_unlock_irqrestore(&mchan
->lock
, flags
);
502 /* Alloc channel resources */
503 static int mpc_dma_alloc_chan_resources(struct dma_chan
*chan
)
505 struct mpc_dma
*mdma
= dma_chan_to_mpc_dma(chan
);
506 struct mpc_dma_chan
*mchan
= dma_chan_to_mpc_dma_chan(chan
);
507 struct mpc_dma_desc
*mdesc
;
508 struct mpc_dma_tcd
*tcd
;
509 dma_addr_t tcd_paddr
;
514 /* Alloc DMA memory for Transfer Control Descriptors */
515 tcd
= dma_alloc_coherent(mdma
->dma
.dev
,
516 MPC_DMA_DESCRIPTORS
* sizeof(struct mpc_dma_tcd
),
517 &tcd_paddr
, GFP_KERNEL
);
521 /* Alloc descriptors for this channel */
522 for (i
= 0; i
< MPC_DMA_DESCRIPTORS
; i
++) {
523 mdesc
= kzalloc(sizeof(struct mpc_dma_desc
), GFP_KERNEL
);
525 dev_notice(mdma
->dma
.dev
, "Memory allocation error. "
526 "Allocated only %u descriptors\n", i
);
530 dma_async_tx_descriptor_init(&mdesc
->desc
, chan
);
531 mdesc
->desc
.flags
= DMA_CTRL_ACK
;
532 mdesc
->desc
.tx_submit
= mpc_dma_tx_submit
;
534 mdesc
->tcd
= &tcd
[i
];
535 mdesc
->tcd_paddr
= tcd_paddr
+ (i
* sizeof(struct mpc_dma_tcd
));
537 list_add_tail(&mdesc
->node
, &descs
);
540 /* Return error only if no descriptors were allocated */
542 dma_free_coherent(mdma
->dma
.dev
,
543 MPC_DMA_DESCRIPTORS
* sizeof(struct mpc_dma_tcd
),
548 spin_lock_irqsave(&mchan
->lock
, flags
);
550 mchan
->tcd_paddr
= tcd_paddr
;
551 list_splice_tail_init(&descs
, &mchan
->free
);
552 spin_unlock_irqrestore(&mchan
->lock
, flags
);
554 /* Enable Error Interrupt */
555 out_8(&mdma
->regs
->dmaseei
, chan
->chan_id
);
560 /* Free channel resources */
561 static void mpc_dma_free_chan_resources(struct dma_chan
*chan
)
563 struct mpc_dma
*mdma
= dma_chan_to_mpc_dma(chan
);
564 struct mpc_dma_chan
*mchan
= dma_chan_to_mpc_dma_chan(chan
);
565 struct mpc_dma_desc
*mdesc
, *tmp
;
566 struct mpc_dma_tcd
*tcd
;
567 dma_addr_t tcd_paddr
;
571 spin_lock_irqsave(&mchan
->lock
, flags
);
573 /* Channel must be idle */
574 BUG_ON(!list_empty(&mchan
->prepared
));
575 BUG_ON(!list_empty(&mchan
->queued
));
576 BUG_ON(!list_empty(&mchan
->active
));
577 BUG_ON(!list_empty(&mchan
->completed
));
580 list_splice_tail_init(&mchan
->free
, &descs
);
582 tcd_paddr
= mchan
->tcd_paddr
;
584 spin_unlock_irqrestore(&mchan
->lock
, flags
);
586 /* Free DMA memory used by descriptors */
587 dma_free_coherent(mdma
->dma
.dev
,
588 MPC_DMA_DESCRIPTORS
* sizeof(struct mpc_dma_tcd
),
591 /* Free descriptors */
592 list_for_each_entry_safe(mdesc
, tmp
, &descs
, node
)
595 /* Disable Error Interrupt */
596 out_8(&mdma
->regs
->dmaceei
, chan
->chan_id
);
599 /* Send all pending descriptor to hardware */
600 static void mpc_dma_issue_pending(struct dma_chan
*chan
)
603 * We are posting descriptors to the hardware as soon as
604 * they are ready, so this function does nothing.
608 /* Check request completion status */
609 static enum dma_status
610 mpc_dma_tx_status(struct dma_chan
*chan
, dma_cookie_t cookie
,
611 struct dma_tx_state
*txstate
)
613 return dma_cookie_status(chan
, cookie
, txstate
);
616 /* Prepare descriptor for memory to memory copy */
617 static struct dma_async_tx_descriptor
*
618 mpc_dma_prep_memcpy(struct dma_chan
*chan
, dma_addr_t dst
, dma_addr_t src
,
619 size_t len
, unsigned long flags
)
621 struct mpc_dma
*mdma
= dma_chan_to_mpc_dma(chan
);
622 struct mpc_dma_chan
*mchan
= dma_chan_to_mpc_dma_chan(chan
);
623 struct mpc_dma_desc
*mdesc
= NULL
;
624 struct mpc_dma_tcd
*tcd
;
625 unsigned long iflags
;
627 /* Get free descriptor */
628 spin_lock_irqsave(&mchan
->lock
, iflags
);
629 if (!list_empty(&mchan
->free
)) {
630 mdesc
= list_first_entry(&mchan
->free
, struct mpc_dma_desc
,
632 list_del(&mdesc
->node
);
634 spin_unlock_irqrestore(&mchan
->lock
, iflags
);
637 /* try to free completed descriptors */
638 mpc_dma_process_completed(mdma
);
643 mdesc
->will_access_peripheral
= 0;
646 /* Prepare Transfer Control Descriptor for this transaction */
647 memset(tcd
, 0, sizeof(struct mpc_dma_tcd
));
649 if (IS_ALIGNED(src
| dst
| len
, 32)) {
650 tcd
->ssize
= MPC_DMA_TSIZE_32
;
651 tcd
->dsize
= MPC_DMA_TSIZE_32
;
654 } else if (!mdma
->is_mpc8308
&& IS_ALIGNED(src
| dst
| len
, 16)) {
655 /* MPC8308 doesn't support 16 byte transfers */
656 tcd
->ssize
= MPC_DMA_TSIZE_16
;
657 tcd
->dsize
= MPC_DMA_TSIZE_16
;
660 } else if (IS_ALIGNED(src
| dst
| len
, 4)) {
661 tcd
->ssize
= MPC_DMA_TSIZE_4
;
662 tcd
->dsize
= MPC_DMA_TSIZE_4
;
665 } else if (IS_ALIGNED(src
| dst
| len
, 2)) {
666 tcd
->ssize
= MPC_DMA_TSIZE_2
;
667 tcd
->dsize
= MPC_DMA_TSIZE_2
;
671 tcd
->ssize
= MPC_DMA_TSIZE_1
;
672 tcd
->dsize
= MPC_DMA_TSIZE_1
;
683 /* Place descriptor in prepared list */
684 spin_lock_irqsave(&mchan
->lock
, iflags
);
685 list_add_tail(&mdesc
->node
, &mchan
->prepared
);
686 spin_unlock_irqrestore(&mchan
->lock
, iflags
);
691 static struct dma_async_tx_descriptor
*
692 mpc_dma_prep_slave_sg(struct dma_chan
*chan
, struct scatterlist
*sgl
,
693 unsigned int sg_len
, enum dma_transfer_direction direction
,
694 unsigned long flags
, void *context
)
696 struct mpc_dma
*mdma
= dma_chan_to_mpc_dma(chan
);
697 struct mpc_dma_chan
*mchan
= dma_chan_to_mpc_dma_chan(chan
);
698 struct mpc_dma_desc
*mdesc
= NULL
;
699 dma_addr_t per_paddr
;
701 struct mpc_dma_tcd
*tcd
;
702 unsigned long iflags
;
703 struct scatterlist
*sg
;
707 /* Currently there is no proper support for scatter/gather */
711 if (!is_slave_direction(direction
))
714 for_each_sg(sgl
, sg
, sg_len
, i
) {
715 spin_lock_irqsave(&mchan
->lock
, iflags
);
717 mdesc
= list_first_entry(&mchan
->free
,
718 struct mpc_dma_desc
, node
);
720 spin_unlock_irqrestore(&mchan
->lock
, iflags
);
721 /* Try to free completed descriptors */
722 mpc_dma_process_completed(mdma
);
726 list_del(&mdesc
->node
);
728 if (direction
== DMA_DEV_TO_MEM
) {
729 per_paddr
= mchan
->src_per_paddr
;
730 tcd_nunits
= mchan
->src_tcd_nunits
;
732 per_paddr
= mchan
->dst_per_paddr
;
733 tcd_nunits
= mchan
->dst_tcd_nunits
;
736 spin_unlock_irqrestore(&mchan
->lock
, iflags
);
738 if (per_paddr
== 0 || tcd_nunits
== 0)
742 mdesc
->will_access_peripheral
= 1;
744 /* Prepare Transfer Control Descriptor for this transaction */
747 memset(tcd
, 0, sizeof(struct mpc_dma_tcd
));
749 if (!IS_ALIGNED(sg_dma_address(sg
), 4))
752 if (direction
== DMA_DEV_TO_MEM
) {
753 tcd
->saddr
= per_paddr
;
754 tcd
->daddr
= sg_dma_address(sg
);
758 tcd
->saddr
= sg_dma_address(sg
);
759 tcd
->daddr
= per_paddr
;
764 tcd
->ssize
= MPC_DMA_TSIZE_4
;
765 tcd
->dsize
= MPC_DMA_TSIZE_4
;
767 len
= sg_dma_len(sg
);
768 tcd
->nbytes
= tcd_nunits
* 4;
769 if (!IS_ALIGNED(len
, tcd
->nbytes
))
772 iter
= len
/ tcd
->nbytes
;
773 if (iter
>= 1 << 15) {
777 /* citer_linkch contains the high bits of iter */
778 tcd
->biter
= iter
& 0x1ff;
779 tcd
->biter_linkch
= iter
>> 9;
780 tcd
->citer
= tcd
->biter
;
781 tcd
->citer_linkch
= tcd
->biter_linkch
;
786 /* Place descriptor in prepared list */
787 spin_lock_irqsave(&mchan
->lock
, iflags
);
788 list_add_tail(&mdesc
->node
, &mchan
->prepared
);
789 spin_unlock_irqrestore(&mchan
->lock
, iflags
);
795 /* Put the descriptor back */
796 spin_lock_irqsave(&mchan
->lock
, iflags
);
797 list_add_tail(&mdesc
->node
, &mchan
->free
);
798 spin_unlock_irqrestore(&mchan
->lock
, iflags
);
803 static int mpc_dma_device_config(struct dma_chan
*chan
,
804 struct dma_slave_config
*cfg
)
806 struct mpc_dma_chan
*mchan
= dma_chan_to_mpc_dma_chan(chan
);
810 * Software constraints:
811 * - only transfers between a peripheral device and
812 * memory are supported;
813 * - only peripheral devices with 4-byte FIFO access register
815 * - minimal transfer chunk is 4 bytes and consequently
816 * source and destination addresses must be 4-byte aligned
817 * and transfer size must be aligned on (4 * maxburst)
819 * - during the transfer RAM address is being incremented by
820 * the size of minimal transfer chunk;
821 * - peripheral port's address is constant during the transfer.
824 if (cfg
->src_addr_width
!= DMA_SLAVE_BUSWIDTH_4_BYTES
||
825 cfg
->dst_addr_width
!= DMA_SLAVE_BUSWIDTH_4_BYTES
||
826 !IS_ALIGNED(cfg
->src_addr
, 4) ||
827 !IS_ALIGNED(cfg
->dst_addr
, 4)) {
831 spin_lock_irqsave(&mchan
->lock
, flags
);
833 mchan
->src_per_paddr
= cfg
->src_addr
;
834 mchan
->src_tcd_nunits
= cfg
->src_maxburst
;
835 mchan
->dst_per_paddr
= cfg
->dst_addr
;
836 mchan
->dst_tcd_nunits
= cfg
->dst_maxburst
;
839 if (mchan
->src_tcd_nunits
== 0)
840 mchan
->src_tcd_nunits
= 1;
841 if (mchan
->dst_tcd_nunits
== 0)
842 mchan
->dst_tcd_nunits
= 1;
844 spin_unlock_irqrestore(&mchan
->lock
, flags
);
849 static int mpc_dma_device_terminate_all(struct dma_chan
*chan
)
851 struct mpc_dma_chan
*mchan
= dma_chan_to_mpc_dma_chan(chan
);
852 struct mpc_dma
*mdma
= dma_chan_to_mpc_dma(chan
);
855 /* Disable channel requests */
856 spin_lock_irqsave(&mchan
->lock
, flags
);
858 out_8(&mdma
->regs
->dmacerq
, chan
->chan_id
);
859 list_splice_tail_init(&mchan
->prepared
, &mchan
->free
);
860 list_splice_tail_init(&mchan
->queued
, &mchan
->free
);
861 list_splice_tail_init(&mchan
->active
, &mchan
->free
);
863 spin_unlock_irqrestore(&mchan
->lock
, flags
);
868 static int mpc_dma_probe(struct platform_device
*op
)
870 struct device_node
*dn
= op
->dev
.of_node
;
871 struct device
*dev
= &op
->dev
;
872 struct dma_device
*dma
;
873 struct mpc_dma
*mdma
;
874 struct mpc_dma_chan
*mchan
;
876 ulong regs_start
, regs_size
;
880 mdma
= devm_kzalloc(dev
, sizeof(struct mpc_dma
), GFP_KERNEL
);
882 dev_err(dev
, "Memory exhausted!\n");
887 mdma
->irq
= irq_of_parse_and_map(dn
, 0);
888 if (mdma
->irq
== NO_IRQ
) {
889 dev_err(dev
, "Error mapping IRQ!\n");
894 if (of_device_is_compatible(dn
, "fsl,mpc8308-dma")) {
895 mdma
->is_mpc8308
= 1;
896 mdma
->irq2
= irq_of_parse_and_map(dn
, 1);
897 if (mdma
->irq2
== NO_IRQ
) {
898 dev_err(dev
, "Error mapping IRQ!\n");
904 retval
= of_address_to_resource(dn
, 0, &res
);
906 dev_err(dev
, "Error parsing memory region!\n");
910 regs_start
= res
.start
;
911 regs_size
= resource_size(&res
);
913 if (!devm_request_mem_region(dev
, regs_start
, regs_size
, DRV_NAME
)) {
914 dev_err(dev
, "Error requesting memory region!\n");
919 mdma
->regs
= devm_ioremap(dev
, regs_start
, regs_size
);
921 dev_err(dev
, "Error mapping memory region!\n");
926 mdma
->tcd
= (struct mpc_dma_tcd
*)((u8
*)(mdma
->regs
)
927 + MPC_DMA_TCD_OFFSET
);
929 retval
= request_irq(mdma
->irq
, &mpc_dma_irq
, 0, DRV_NAME
, mdma
);
931 dev_err(dev
, "Error requesting IRQ!\n");
936 if (mdma
->is_mpc8308
) {
937 retval
= request_irq(mdma
->irq2
, &mpc_dma_irq
, 0,
940 dev_err(dev
, "Error requesting IRQ2!\n");
946 spin_lock_init(&mdma
->error_status_lock
);
950 dma
->device_alloc_chan_resources
= mpc_dma_alloc_chan_resources
;
951 dma
->device_free_chan_resources
= mpc_dma_free_chan_resources
;
952 dma
->device_issue_pending
= mpc_dma_issue_pending
;
953 dma
->device_tx_status
= mpc_dma_tx_status
;
954 dma
->device_prep_dma_memcpy
= mpc_dma_prep_memcpy
;
955 dma
->device_prep_slave_sg
= mpc_dma_prep_slave_sg
;
956 dma
->device_config
= mpc_dma_device_config
;
957 dma
->device_terminate_all
= mpc_dma_device_terminate_all
;
959 INIT_LIST_HEAD(&dma
->channels
);
960 dma_cap_set(DMA_MEMCPY
, dma
->cap_mask
);
961 dma_cap_set(DMA_SLAVE
, dma
->cap_mask
);
963 if (mdma
->is_mpc8308
)
964 chancnt
= MPC8308_DMACHAN_MAX
;
966 chancnt
= MPC512x_DMACHAN_MAX
;
968 for (i
= 0; i
< chancnt
; i
++) {
969 mchan
= &mdma
->channels
[i
];
971 mchan
->chan
.device
= dma
;
972 dma_cookie_init(&mchan
->chan
);
974 INIT_LIST_HEAD(&mchan
->free
);
975 INIT_LIST_HEAD(&mchan
->prepared
);
976 INIT_LIST_HEAD(&mchan
->queued
);
977 INIT_LIST_HEAD(&mchan
->active
);
978 INIT_LIST_HEAD(&mchan
->completed
);
980 spin_lock_init(&mchan
->lock
);
981 list_add_tail(&mchan
->chan
.device_node
, &dma
->channels
);
984 tasklet_init(&mdma
->tasklet
, mpc_dma_tasklet
, (unsigned long)mdma
);
987 * Configure DMA Engine:
989 * - Round-robin group arbitration,
990 * - Round-robin channel arbitration.
992 if (mdma
->is_mpc8308
) {
993 /* MPC8308 has 16 channels and lacks some registers */
994 out_be32(&mdma
->regs
->dmacr
, MPC_DMA_DMACR_ERCA
);
996 /* enable snooping */
997 out_be32(&mdma
->regs
->dmagpor
, MPC_DMA_DMAGPOR_SNOOP_ENABLE
);
998 /* Disable error interrupts */
999 out_be32(&mdma
->regs
->dmaeeil
, 0);
1001 /* Clear interrupts status */
1002 out_be32(&mdma
->regs
->dmaintl
, 0xFFFF);
1003 out_be32(&mdma
->regs
->dmaerrl
, 0xFFFF);
1005 out_be32(&mdma
->regs
->dmacr
, MPC_DMA_DMACR_EDCG
|
1006 MPC_DMA_DMACR_ERGA
| MPC_DMA_DMACR_ERCA
);
1008 /* Disable hardware DMA requests */
1009 out_be32(&mdma
->regs
->dmaerqh
, 0);
1010 out_be32(&mdma
->regs
->dmaerql
, 0);
1012 /* Disable error interrupts */
1013 out_be32(&mdma
->regs
->dmaeeih
, 0);
1014 out_be32(&mdma
->regs
->dmaeeil
, 0);
1016 /* Clear interrupts status */
1017 out_be32(&mdma
->regs
->dmainth
, 0xFFFFFFFF);
1018 out_be32(&mdma
->regs
->dmaintl
, 0xFFFFFFFF);
1019 out_be32(&mdma
->regs
->dmaerrh
, 0xFFFFFFFF);
1020 out_be32(&mdma
->regs
->dmaerrl
, 0xFFFFFFFF);
1022 /* Route interrupts to IPIC */
1023 out_be32(&mdma
->regs
->dmaihsa
, 0);
1024 out_be32(&mdma
->regs
->dmailsa
, 0);
1027 /* Register DMA engine */
1028 dev_set_drvdata(dev
, mdma
);
1029 retval
= dma_async_device_register(dma
);
1033 /* Register with OF helpers for DMA lookups (nonfatal) */
1035 retval
= of_dma_controller_register(dev
->of_node
,
1036 of_dma_xlate_by_chan_id
, mdma
);
1038 dev_warn(dev
, "Could not register for OF lookup\n");
1044 if (mdma
->is_mpc8308
)
1045 free_irq(mdma
->irq2
, mdma
);
1047 free_irq(mdma
->irq
, mdma
);
1049 if (mdma
->is_mpc8308
)
1050 irq_dispose_mapping(mdma
->irq2
);
1052 irq_dispose_mapping(mdma
->irq
);
1057 static int mpc_dma_remove(struct platform_device
*op
)
1059 struct device
*dev
= &op
->dev
;
1060 struct mpc_dma
*mdma
= dev_get_drvdata(dev
);
1063 of_dma_controller_free(dev
->of_node
);
1064 dma_async_device_unregister(&mdma
->dma
);
1065 if (mdma
->is_mpc8308
) {
1066 free_irq(mdma
->irq2
, mdma
);
1067 irq_dispose_mapping(mdma
->irq2
);
1069 free_irq(mdma
->irq
, mdma
);
1070 irq_dispose_mapping(mdma
->irq
);
1075 static struct of_device_id mpc_dma_match
[] = {
1076 { .compatible
= "fsl,mpc5121-dma", },
1077 { .compatible
= "fsl,mpc8308-dma", },
1081 static struct platform_driver mpc_dma_driver
= {
1082 .probe
= mpc_dma_probe
,
1083 .remove
= mpc_dma_remove
,
1086 .of_match_table
= mpc_dma_match
,
1090 module_platform_driver(mpc_dma_driver
);
1092 MODULE_LICENSE("GPL");
1093 MODULE_AUTHOR("Piotr Ziecik <kosmo@semihalf.com>");