2 * Renesas SuperH DMA Engine support
4 * base is drivers/dma/flsdma.c
6 * Copyright (C) 2009 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
7 * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved.
8 * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
10 * This is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * - DMA of SuperH does not have Hardware DMA chain mode.
16 * - MAX DMA size is 16MB.
20 #include <linux/init.h>
21 #include <linux/module.h>
22 #include <linux/slab.h>
23 #include <linux/interrupt.h>
24 #include <linux/dmaengine.h>
25 #include <linux/delay.h>
26 #include <linux/dma-mapping.h>
27 #include <linux/platform_device.h>
28 #include <linux/pm_runtime.h>
29 #include <linux/sh_dma.h>
30 #include <linux/notifier.h>
31 #include <linux/kdebug.h>
32 #include <linux/spinlock.h>
33 #include <linux/rculist.h>
36 /* DMA descriptor control */
37 enum sh_dmae_desc_status {
41 DESC_COMPLETED, /* completed, have to call callback */
42 DESC_WAITING, /* callback called, waiting for ack / re-submit */
45 #define NR_DESCS_PER_CHANNEL 32
46 /* Default MEMCPY transfer size = 2^2 = 4 bytes */
47 #define LOG2_DEFAULT_XFER_SIZE 2
50 * Used for write-side mutual exclusion for the global device list,
51 * read-side synchronization by way of RCU, and per-controller data.
53 static DEFINE_SPINLOCK(sh_dmae_lock);
54 static LIST_HEAD(sh_dmae_devices);
56 /* A bitmask with bits enough for enum sh_dmae_slave_chan_id */
57 static unsigned long sh_dmae_slave_used[BITS_TO_LONGS(SH_DMA_SLAVE_NUMBER)];
59 static void sh_dmae_chan_ld_cleanup(struct sh_dmae_chan *sh_chan, bool all);
61 static void sh_dmae_writel(struct sh_dmae_chan *sh_dc, u32 data, u32 reg)
63 __raw_writel(data, sh_dc->base + reg / sizeof(u32));
66 static u32 sh_dmae_readl(struct sh_dmae_chan *sh_dc, u32 reg)
68 return __raw_readl(sh_dc->base + reg / sizeof(u32));
71 static u16 dmaor_read(struct sh_dmae_device *shdev)
73 u32 __iomem *addr = shdev->chan_reg + DMAOR / sizeof(u32);
75 if (shdev->pdata->dmaor_is_32bit)
76 return __raw_readl(addr);
78 return __raw_readw(addr);
81 static void dmaor_write(struct sh_dmae_device *shdev, u16 data)
83 u32 __iomem *addr = shdev->chan_reg + DMAOR / sizeof(u32);
85 if (shdev->pdata->dmaor_is_32bit)
86 __raw_writel(data, addr);
88 __raw_writew(data, addr);
91 static void chcr_write(struct sh_dmae_chan *sh_dc, u32 data)
93 struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
95 __raw_writel(data, sh_dc->base + shdev->chcr_offset / sizeof(u32));
98 static u32 chcr_read(struct sh_dmae_chan *sh_dc)
100 struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
102 return __raw_readl(sh_dc->base + shdev->chcr_offset / sizeof(u32));
106 * Reset DMA controller
108 * SH7780 has two DMAOR register
110 static void sh_dmae_ctl_stop(struct sh_dmae_device *shdev)
112 unsigned short dmaor;
115 spin_lock_irqsave(&sh_dmae_lock, flags);
117 dmaor = dmaor_read(shdev);
118 dmaor_write(shdev, dmaor & ~(DMAOR_NMIF | DMAOR_AE | DMAOR_DME));
120 spin_unlock_irqrestore(&sh_dmae_lock, flags);
123 static int sh_dmae_rst(struct sh_dmae_device *shdev)
125 unsigned short dmaor;
128 spin_lock_irqsave(&sh_dmae_lock, flags);
130 dmaor = dmaor_read(shdev) & ~(DMAOR_NMIF | DMAOR_AE | DMAOR_DME);
132 dmaor_write(shdev, dmaor | shdev->pdata->dmaor_init);
134 dmaor = dmaor_read(shdev);
136 spin_unlock_irqrestore(&sh_dmae_lock, flags);
138 if (dmaor & (DMAOR_AE | DMAOR_NMIF)) {
139 dev_warn(shdev->common.dev, "Can't initialize DMAOR.\n");
145 static bool dmae_is_busy(struct sh_dmae_chan *sh_chan)
147 u32 chcr = chcr_read(sh_chan);
149 if ((chcr & (CHCR_DE | CHCR_TE)) == CHCR_DE)
150 return true; /* working */
152 return false; /* waiting */
155 static unsigned int calc_xmit_shift(struct sh_dmae_chan *sh_chan, u32 chcr)
157 struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
158 struct sh_dmae_pdata *pdata = shdev->pdata;
159 int cnt = ((chcr & pdata->ts_low_mask) >> pdata->ts_low_shift) |
160 ((chcr & pdata->ts_high_mask) >> pdata->ts_high_shift);
162 if (cnt >= pdata->ts_shift_num)
165 return pdata->ts_shift[cnt];
168 static u32 log2size_to_chcr(struct sh_dmae_chan *sh_chan, int l2size)
170 struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
171 struct sh_dmae_pdata *pdata = shdev->pdata;
174 for (i = 0; i < pdata->ts_shift_num; i++)
175 if (pdata->ts_shift[i] == l2size)
178 if (i == pdata->ts_shift_num)
181 return ((i << pdata->ts_low_shift) & pdata->ts_low_mask) |
182 ((i << pdata->ts_high_shift) & pdata->ts_high_mask);
185 static void dmae_set_reg(struct sh_dmae_chan *sh_chan, struct sh_dmae_regs *hw)
187 sh_dmae_writel(sh_chan, hw->sar, SAR);
188 sh_dmae_writel(sh_chan, hw->dar, DAR);
189 sh_dmae_writel(sh_chan, hw->tcr >> sh_chan->xmit_shift, TCR);
192 static void dmae_start(struct sh_dmae_chan *sh_chan)
194 struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
195 u32 chcr = chcr_read(sh_chan);
197 if (shdev->pdata->needs_tend_set)
198 sh_dmae_writel(sh_chan, 0xFFFFFFFF, TEND);
200 chcr |= CHCR_DE | shdev->chcr_ie_bit;
201 chcr_write(sh_chan, chcr & ~CHCR_TE);
204 static void dmae_halt(struct sh_dmae_chan *sh_chan)
206 struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
207 u32 chcr = chcr_read(sh_chan);
209 chcr &= ~(CHCR_DE | CHCR_TE | shdev->chcr_ie_bit);
210 chcr_write(sh_chan, chcr);
213 static void dmae_init(struct sh_dmae_chan *sh_chan)
216 * Default configuration for dual address memory-memory transfer.
217 * 0x400 represents auto-request.
219 u32 chcr = DM_INC | SM_INC | 0x400 | log2size_to_chcr(sh_chan,
220 LOG2_DEFAULT_XFER_SIZE);
221 sh_chan->xmit_shift = calc_xmit_shift(sh_chan, chcr);
222 chcr_write(sh_chan, chcr);
225 static int dmae_set_chcr(struct sh_dmae_chan *sh_chan, u32 val)
227 /* If DMA is active, cannot set CHCR. TODO: remove this superfluous check */
228 if (dmae_is_busy(sh_chan))
231 sh_chan->xmit_shift = calc_xmit_shift(sh_chan, val);
232 chcr_write(sh_chan, val);
237 static int dmae_set_dmars(struct sh_dmae_chan *sh_chan, u16 val)
239 struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
240 struct sh_dmae_pdata *pdata = shdev->pdata;
241 const struct sh_dmae_channel *chan_pdata = &pdata->channel[sh_chan->id];
242 u16 __iomem *addr = shdev->dmars;
243 unsigned int shift = chan_pdata->dmars_bit;
245 if (dmae_is_busy(sh_chan))
251 /* in the case of a missing DMARS resource use first memory window */
253 addr = (u16 __iomem *)shdev->chan_reg;
254 addr += chan_pdata->dmars / sizeof(u16);
256 __raw_writew((__raw_readw(addr) & (0xff00 >> shift)) | (val << shift),
262 static void sh_chan_xfer_ld_queue(struct sh_dmae_chan *sh_chan);
264 static dma_cookie_t sh_dmae_tx_submit(struct dma_async_tx_descriptor *tx)
266 struct sh_desc *desc = tx_to_sh_desc(tx), *chunk, *last = desc, *c;
267 struct sh_dmae_chan *sh_chan = to_sh_chan(tx->chan);
268 struct sh_dmae_slave *param = tx->chan->private;
269 dma_async_tx_callback callback = tx->callback;
273 spin_lock_irq(&sh_chan->desc_lock);
275 if (list_empty(&sh_chan->ld_queue))
280 cookie = sh_chan->common.cookie;
285 sh_chan->common.cookie = cookie;
288 /* Mark all chunks of this descriptor as submitted, move to the queue */
289 list_for_each_entry_safe(chunk, c, desc->node.prev, node) {
291 * All chunks are on the global ld_free, so, we have to find
292 * the end of the chain ourselves
294 if (chunk != desc && (chunk->mark == DESC_IDLE ||
295 chunk->async_tx.cookie > 0 ||
296 chunk->async_tx.cookie == -EBUSY ||
297 &chunk->node == &sh_chan->ld_free))
299 chunk->mark = DESC_SUBMITTED;
300 /* Callback goes to the last chunk */
301 chunk->async_tx.callback = NULL;
302 chunk->cookie = cookie;
303 list_move_tail(&chunk->node, &sh_chan->ld_queue);
307 last->async_tx.callback = callback;
308 last->async_tx.callback_param = tx->callback_param;
310 dev_dbg(sh_chan->dev, "submit #%d@%p on %d: %x[%d] -> %x\n",
311 tx->cookie, &last->async_tx, sh_chan->id,
312 desc->hw.sar, desc->hw.tcr, desc->hw.dar);
315 sh_chan->pm_state = DMAE_PM_BUSY;
317 pm_runtime_get(sh_chan->dev);
319 spin_unlock_irq(&sh_chan->desc_lock);
321 pm_runtime_barrier(sh_chan->dev);
323 spin_lock_irq(&sh_chan->desc_lock);
325 /* Have we been reset, while waiting? */
326 if (sh_chan->pm_state != DMAE_PM_ESTABLISHED) {
327 dev_dbg(sh_chan->dev, "Bring up channel %d\n",
330 const struct sh_dmae_slave_config *cfg =
333 dmae_set_dmars(sh_chan, cfg->mid_rid);
334 dmae_set_chcr(sh_chan, cfg->chcr);
339 if (sh_chan->pm_state == DMAE_PM_PENDING)
340 sh_chan_xfer_ld_queue(sh_chan);
341 sh_chan->pm_state = DMAE_PM_ESTABLISHED;
345 spin_unlock_irq(&sh_chan->desc_lock);
350 /* Called with desc_lock held */
351 static struct sh_desc *sh_dmae_get_desc(struct sh_dmae_chan *sh_chan)
353 struct sh_desc *desc;
355 list_for_each_entry(desc, &sh_chan->ld_free, node)
356 if (desc->mark != DESC_PREPARED) {
357 BUG_ON(desc->mark != DESC_IDLE);
358 list_del(&desc->node);
365 static const struct sh_dmae_slave_config *sh_dmae_find_slave(
366 struct sh_dmae_chan *sh_chan, struct sh_dmae_slave *param)
368 struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
369 struct sh_dmae_pdata *pdata = shdev->pdata;
372 if (param->slave_id >= SH_DMA_SLAVE_NUMBER)
375 for (i = 0; i < pdata->slave_num; i++)
376 if (pdata->slave[i].slave_id == param->slave_id)
377 return pdata->slave + i;
382 static int sh_dmae_alloc_chan_resources(struct dma_chan *chan)
384 struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
385 struct sh_desc *desc;
386 struct sh_dmae_slave *param = chan->private;
390 * This relies on the guarantee from dmaengine that alloc_chan_resources
391 * never runs concurrently with itself or free_chan_resources.
394 const struct sh_dmae_slave_config *cfg;
396 cfg = sh_dmae_find_slave(sh_chan, param);
402 if (test_and_set_bit(param->slave_id, sh_dmae_slave_used)) {
410 while (sh_chan->descs_allocated < NR_DESCS_PER_CHANNEL) {
411 desc = kzalloc(sizeof(struct sh_desc), GFP_KERNEL);
414 dma_async_tx_descriptor_init(&desc->async_tx,
416 desc->async_tx.tx_submit = sh_dmae_tx_submit;
417 desc->mark = DESC_IDLE;
419 list_add(&desc->node, &sh_chan->ld_free);
420 sh_chan->descs_allocated++;
423 if (!sh_chan->descs_allocated) {
428 return sh_chan->descs_allocated;
432 clear_bit(param->slave_id, sh_dmae_slave_used);
435 chan->private = NULL;
440 * sh_dma_free_chan_resources - Free all resources of the channel.
442 static void sh_dmae_free_chan_resources(struct dma_chan *chan)
444 struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
445 struct sh_desc *desc, *_desc;
448 /* Protect against ISR */
449 spin_lock_irq(&sh_chan->desc_lock);
451 spin_unlock_irq(&sh_chan->desc_lock);
453 /* Now no new interrupts will occur */
455 /* Prepared and not submitted descriptors can still be on the queue */
456 if (!list_empty(&sh_chan->ld_queue))
457 sh_dmae_chan_ld_cleanup(sh_chan, true);
460 /* The caller is holding dma_list_mutex */
461 struct sh_dmae_slave *param = chan->private;
462 clear_bit(param->slave_id, sh_dmae_slave_used);
463 chan->private = NULL;
466 spin_lock_irq(&sh_chan->desc_lock);
468 list_splice_init(&sh_chan->ld_free, &list);
469 sh_chan->descs_allocated = 0;
471 spin_unlock_irq(&sh_chan->desc_lock);
473 list_for_each_entry_safe(desc, _desc, &list, node)
478 * sh_dmae_add_desc - get, set up and return one transfer descriptor
479 * @sh_chan: DMA channel
480 * @flags: DMA transfer flags
481 * @dest: destination DMA address, incremented when direction equals
482 * DMA_FROM_DEVICE or DMA_BIDIRECTIONAL
483 * @src: source DMA address, incremented when direction equals
484 * DMA_TO_DEVICE or DMA_BIDIRECTIONAL
485 * @len: DMA transfer length
486 * @first: if NULL, set to the current descriptor and cookie set to -EBUSY
487 * @direction: needed for slave DMA to decide which address to keep constant,
488 * equals DMA_BIDIRECTIONAL for MEMCPY
489 * Returns 0 or an error
490 * Locks: called with desc_lock held
492 static struct sh_desc *sh_dmae_add_desc(struct sh_dmae_chan *sh_chan,
493 unsigned long flags, dma_addr_t *dest, dma_addr_t *src, size_t *len,
494 struct sh_desc **first, enum dma_data_direction direction)
502 /* Allocate the link descriptor from the free list */
503 new = sh_dmae_get_desc(sh_chan);
505 dev_err(sh_chan->dev, "No free link descriptor available\n");
509 copy_size = min(*len, (size_t)SH_DMA_TCR_MAX + 1);
513 new->hw.tcr = copy_size;
517 new->async_tx.cookie = -EBUSY;
520 /* Other desc - invisible to the user */
521 new->async_tx.cookie = -EINVAL;
524 dev_dbg(sh_chan->dev,
525 "chaining (%u/%u)@%x -> %x with %p, cookie %d, shift %d\n",
526 copy_size, *len, *src, *dest, &new->async_tx,
527 new->async_tx.cookie, sh_chan->xmit_shift);
529 new->mark = DESC_PREPARED;
530 new->async_tx.flags = flags;
531 new->direction = direction;
534 if (direction == DMA_BIDIRECTIONAL || direction == DMA_TO_DEVICE)
536 if (direction == DMA_BIDIRECTIONAL || direction == DMA_FROM_DEVICE)
543 * sh_dmae_prep_sg - prepare transfer descriptors from an SG list
545 * Common routine for public (MEMCPY) and slave DMA. The MEMCPY case is also
546 * converted to scatter-gather to guarantee consistent locking and a correct
547 * list manipulation. For slave DMA direction carries the usual meaning, and,
548 * logically, the SG list is RAM and the addr variable contains slave address,
549 * e.g., the FIFO I/O register. For MEMCPY direction equals DMA_BIDIRECTIONAL
550 * and the SG list contains only one element and points at the source buffer.
552 static struct dma_async_tx_descriptor *sh_dmae_prep_sg(struct sh_dmae_chan *sh_chan,
553 struct scatterlist *sgl, unsigned int sg_len, dma_addr_t *addr,
554 enum dma_data_direction direction, unsigned long flags)
556 struct scatterlist *sg;
557 struct sh_desc *first = NULL, *new = NULL /* compiler... */;
560 unsigned long irq_flags;
566 for_each_sg(sgl, sg, sg_len, i)
567 chunks += (sg_dma_len(sg) + SH_DMA_TCR_MAX) /
568 (SH_DMA_TCR_MAX + 1);
570 /* Have to lock the whole loop to protect against concurrent release */
571 spin_lock_irqsave(&sh_chan->desc_lock, irq_flags);
575 * first descriptor is what user is dealing with in all API calls, its
576 * cookie is at first set to -EBUSY, at tx-submit to a positive
578 * if more than one chunk is needed further chunks have cookie = -EINVAL
579 * the last chunk, if not equal to the first, has cookie = -ENOSPC
580 * all chunks are linked onto the tx_list head with their .node heads
581 * only during this function, then they are immediately spliced
582 * back onto the free list in form of a chain
584 for_each_sg(sgl, sg, sg_len, i) {
585 dma_addr_t sg_addr = sg_dma_address(sg);
586 size_t len = sg_dma_len(sg);
592 dev_dbg(sh_chan->dev, "Add SG #%d@%p[%d], dma %llx\n",
593 i, sg, len, (unsigned long long)sg_addr);
595 if (direction == DMA_FROM_DEVICE)
596 new = sh_dmae_add_desc(sh_chan, flags,
597 &sg_addr, addr, &len, &first,
600 new = sh_dmae_add_desc(sh_chan, flags,
601 addr, &sg_addr, &len, &first,
606 new->chunks = chunks--;
607 list_add_tail(&new->node, &tx_list);
612 new->async_tx.cookie = -ENOSPC;
614 /* Put them back on the free list, so, they don't get lost */
615 list_splice_tail(&tx_list, &sh_chan->ld_free);
617 spin_unlock_irqrestore(&sh_chan->desc_lock, irq_flags);
619 return &first->async_tx;
622 list_for_each_entry(new, &tx_list, node)
623 new->mark = DESC_IDLE;
624 list_splice(&tx_list, &sh_chan->ld_free);
626 spin_unlock_irqrestore(&sh_chan->desc_lock, irq_flags);
631 static struct dma_async_tx_descriptor *sh_dmae_prep_memcpy(
632 struct dma_chan *chan, dma_addr_t dma_dest, dma_addr_t dma_src,
633 size_t len, unsigned long flags)
635 struct sh_dmae_chan *sh_chan;
636 struct scatterlist sg;
641 sh_chan = to_sh_chan(chan);
643 sg_init_table(&sg, 1);
644 sg_set_page(&sg, pfn_to_page(PFN_DOWN(dma_src)), len,
645 offset_in_page(dma_src));
646 sg_dma_address(&sg) = dma_src;
647 sg_dma_len(&sg) = len;
649 return sh_dmae_prep_sg(sh_chan, &sg, 1, &dma_dest, DMA_BIDIRECTIONAL,
653 static struct dma_async_tx_descriptor *sh_dmae_prep_slave_sg(
654 struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len,
655 enum dma_data_direction direction, unsigned long flags)
657 struct sh_dmae_slave *param;
658 struct sh_dmae_chan *sh_chan;
659 dma_addr_t slave_addr;
664 sh_chan = to_sh_chan(chan);
665 param = chan->private;
667 /* Someone calling slave DMA on a public channel? */
668 if (!param || !sg_len) {
669 dev_warn(sh_chan->dev, "%s: bad parameter: %p, %d, %d\n",
670 __func__, param, sg_len, param ? param->slave_id : -1);
674 slave_addr = param->config->addr;
677 * if (param != NULL), this is a successfully requested slave channel,
678 * therefore param->config != NULL too.
680 return sh_dmae_prep_sg(sh_chan, sgl, sg_len, &slave_addr,
684 static int sh_dmae_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
687 struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
690 /* Only supports DMA_TERMINATE_ALL */
691 if (cmd != DMA_TERMINATE_ALL)
697 spin_lock_irqsave(&sh_chan->desc_lock, flags);
700 if (!list_empty(&sh_chan->ld_queue)) {
701 /* Record partial transfer */
702 struct sh_desc *desc = list_entry(sh_chan->ld_queue.next,
703 struct sh_desc, node);
704 desc->partial = (desc->hw.tcr - sh_dmae_readl(sh_chan, TCR)) <<
707 spin_unlock_irqrestore(&sh_chan->desc_lock, flags);
709 sh_dmae_chan_ld_cleanup(sh_chan, true);
714 static dma_async_tx_callback __ld_cleanup(struct sh_dmae_chan *sh_chan, bool all)
716 struct sh_desc *desc, *_desc;
717 /* Is the "exposed" head of a chain acked? */
718 bool head_acked = false;
719 dma_cookie_t cookie = 0;
720 dma_async_tx_callback callback = NULL;
724 spin_lock_irqsave(&sh_chan->desc_lock, flags);
725 list_for_each_entry_safe(desc, _desc, &sh_chan->ld_queue, node) {
726 struct dma_async_tx_descriptor *tx = &desc->async_tx;
728 BUG_ON(tx->cookie > 0 && tx->cookie != desc->cookie);
729 BUG_ON(desc->mark != DESC_SUBMITTED &&
730 desc->mark != DESC_COMPLETED &&
731 desc->mark != DESC_WAITING);
734 * queue is ordered, and we use this loop to (1) clean up all
735 * completed descriptors, and to (2) update descriptor flags of
736 * any chunks in a (partially) completed chain
738 if (!all && desc->mark == DESC_SUBMITTED &&
739 desc->cookie != cookie)
745 if (desc->mark == DESC_COMPLETED && desc->chunks == 1) {
746 if (sh_chan->completed_cookie != desc->cookie - 1)
747 dev_dbg(sh_chan->dev,
748 "Completing cookie %d, expected %d\n",
750 sh_chan->completed_cookie + 1);
751 sh_chan->completed_cookie = desc->cookie;
754 /* Call callback on the last chunk */
755 if (desc->mark == DESC_COMPLETED && tx->callback) {
756 desc->mark = DESC_WAITING;
757 callback = tx->callback;
758 param = tx->callback_param;
759 dev_dbg(sh_chan->dev, "descriptor #%d@%p on %d callback\n",
760 tx->cookie, tx, sh_chan->id);
761 BUG_ON(desc->chunks != 1);
765 if (tx->cookie > 0 || tx->cookie == -EBUSY) {
766 if (desc->mark == DESC_COMPLETED) {
767 BUG_ON(tx->cookie < 0);
768 desc->mark = DESC_WAITING;
770 head_acked = async_tx_test_ack(tx);
772 switch (desc->mark) {
774 desc->mark = DESC_WAITING;
778 async_tx_ack(&desc->async_tx);
782 dev_dbg(sh_chan->dev, "descriptor %p #%d completed.\n",
785 if (((desc->mark == DESC_COMPLETED ||
786 desc->mark == DESC_WAITING) &&
787 async_tx_test_ack(&desc->async_tx)) || all) {
788 /* Remove from ld_queue list */
789 desc->mark = DESC_IDLE;
791 list_move(&desc->node, &sh_chan->ld_free);
793 if (list_empty(&sh_chan->ld_queue)) {
794 dev_dbg(sh_chan->dev, "Bring down channel %d\n", sh_chan->id);
795 pm_runtime_put(sh_chan->dev);
800 if (all && !callback)
802 * Terminating and the loop completed normally: forgive
803 * uncompleted cookies
805 sh_chan->completed_cookie = sh_chan->common.cookie;
807 spin_unlock_irqrestore(&sh_chan->desc_lock, flags);
816 * sh_chan_ld_cleanup - Clean up link descriptors
818 * This function cleans up the ld_queue of DMA channel.
820 static void sh_dmae_chan_ld_cleanup(struct sh_dmae_chan *sh_chan, bool all)
822 while (__ld_cleanup(sh_chan, all))
826 /* Called under spin_lock_irq(&sh_chan->desc_lock) */
827 static void sh_chan_xfer_ld_queue(struct sh_dmae_chan *sh_chan)
829 struct sh_desc *desc;
832 if (dmae_is_busy(sh_chan))
835 /* Find the first not transferred descriptor */
836 list_for_each_entry(desc, &sh_chan->ld_queue, node)
837 if (desc->mark == DESC_SUBMITTED) {
838 dev_dbg(sh_chan->dev, "Queue #%d to %d: %u@%x -> %x\n",
839 desc->async_tx.cookie, sh_chan->id,
840 desc->hw.tcr, desc->hw.sar, desc->hw.dar);
841 /* Get the ld start address from ld_queue */
842 dmae_set_reg(sh_chan, &desc->hw);
848 static void sh_dmae_memcpy_issue_pending(struct dma_chan *chan)
850 struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
852 spin_lock_irq(&sh_chan->desc_lock);
853 if (sh_chan->pm_state == DMAE_PM_ESTABLISHED)
854 sh_chan_xfer_ld_queue(sh_chan);
856 sh_chan->pm_state = DMAE_PM_PENDING;
857 spin_unlock_irq(&sh_chan->desc_lock);
860 static enum dma_status sh_dmae_tx_status(struct dma_chan *chan,
862 struct dma_tx_state *txstate)
864 struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
865 dma_cookie_t last_used;
866 dma_cookie_t last_complete;
867 enum dma_status status;
870 sh_dmae_chan_ld_cleanup(sh_chan, false);
872 /* First read completed cookie to avoid a skew */
873 last_complete = sh_chan->completed_cookie;
875 last_used = chan->cookie;
876 BUG_ON(last_complete < 0);
877 dma_set_tx_state(txstate, last_complete, last_used, 0);
879 spin_lock_irqsave(&sh_chan->desc_lock, flags);
881 status = dma_async_is_complete(cookie, last_complete, last_used);
884 * If we don't find cookie on the queue, it has been aborted and we have
887 if (status != DMA_SUCCESS) {
888 struct sh_desc *desc;
890 list_for_each_entry(desc, &sh_chan->ld_queue, node)
891 if (desc->cookie == cookie) {
892 status = DMA_IN_PROGRESS;
897 spin_unlock_irqrestore(&sh_chan->desc_lock, flags);
902 static irqreturn_t sh_dmae_interrupt(int irq, void *data)
904 irqreturn_t ret = IRQ_NONE;
905 struct sh_dmae_chan *sh_chan = data;
908 spin_lock(&sh_chan->desc_lock);
910 chcr = chcr_read(sh_chan);
912 if (chcr & CHCR_TE) {
917 tasklet_schedule(&sh_chan->tasklet);
920 spin_unlock(&sh_chan->desc_lock);
925 /* Called from error IRQ or NMI */
926 static bool sh_dmae_reset(struct sh_dmae_device *shdev)
928 unsigned int handled = 0;
931 /* halt the dma controller */
932 sh_dmae_ctl_stop(shdev);
934 /* We cannot detect, which channel caused the error, have to reset all */
935 for (i = 0; i < SH_DMAC_MAX_CHANNELS; i++) {
936 struct sh_dmae_chan *sh_chan = shdev->chan[i];
937 struct sh_desc *desc;
943 spin_lock(&sh_chan->desc_lock);
945 /* Stop the channel */
948 list_splice_init(&sh_chan->ld_queue, &dl);
950 if (!list_empty(&dl)) {
951 dev_dbg(sh_chan->dev, "Bring down channel %d\n", sh_chan->id);
952 pm_runtime_put(sh_chan->dev);
954 sh_chan->pm_state = DMAE_PM_ESTABLISHED;
956 spin_unlock(&sh_chan->desc_lock);
959 list_for_each_entry(desc, &dl, node) {
960 struct dma_async_tx_descriptor *tx = &desc->async_tx;
961 desc->mark = DESC_IDLE;
963 tx->callback(tx->callback_param);
966 spin_lock(&sh_chan->desc_lock);
967 list_splice(&dl, &sh_chan->ld_free);
968 spin_unlock(&sh_chan->desc_lock);
978 static irqreturn_t sh_dmae_err(int irq, void *data)
980 struct sh_dmae_device *shdev = data;
982 if (!(dmaor_read(shdev) & DMAOR_AE))
989 static void dmae_do_tasklet(unsigned long data)
991 struct sh_dmae_chan *sh_chan = (struct sh_dmae_chan *)data;
992 struct sh_desc *desc;
993 u32 sar_buf = sh_dmae_readl(sh_chan, SAR);
994 u32 dar_buf = sh_dmae_readl(sh_chan, DAR);
996 spin_lock_irq(&sh_chan->desc_lock);
997 list_for_each_entry(desc, &sh_chan->ld_queue, node) {
998 if (desc->mark == DESC_SUBMITTED &&
999 ((desc->direction == DMA_FROM_DEVICE &&
1000 (desc->hw.dar + desc->hw.tcr) == dar_buf) ||
1001 (desc->hw.sar + desc->hw.tcr) == sar_buf)) {
1002 dev_dbg(sh_chan->dev, "done #%d@%p dst %u\n",
1003 desc->async_tx.cookie, &desc->async_tx,
1005 desc->mark = DESC_COMPLETED;
1010 sh_chan_xfer_ld_queue(sh_chan);
1011 spin_unlock_irq(&sh_chan->desc_lock);
1013 sh_dmae_chan_ld_cleanup(sh_chan, false);
1016 static bool sh_dmae_nmi_notify(struct sh_dmae_device *shdev)
1018 /* Fast path out if NMIF is not asserted for this controller */
1019 if ((dmaor_read(shdev) & DMAOR_NMIF) == 0)
1022 return sh_dmae_reset(shdev);
1025 static int sh_dmae_nmi_handler(struct notifier_block *self,
1026 unsigned long cmd, void *data)
1028 struct sh_dmae_device *shdev;
1029 int ret = NOTIFY_DONE;
1033 * Only concern ourselves with NMI events.
1035 * Normally we would check the die chain value, but as this needs
1036 * to be architecture independent, check for NMI context instead.
1042 list_for_each_entry_rcu(shdev, &sh_dmae_devices, node) {
1044 * Only stop if one of the controllers has NMIF asserted,
1045 * we do not want to interfere with regular address error
1046 * handling or NMI events that don't concern the DMACs.
1048 triggered = sh_dmae_nmi_notify(shdev);
1049 if (triggered == true)
1057 static struct notifier_block sh_dmae_nmi_notifier __read_mostly = {
1058 .notifier_call = sh_dmae_nmi_handler,
1060 /* Run before NMI debug handler and KGDB */
1064 static int __devinit sh_dmae_chan_probe(struct sh_dmae_device *shdev, int id,
1065 int irq, unsigned long flags)
1068 const struct sh_dmae_channel *chan_pdata = &shdev->pdata->channel[id];
1069 struct platform_device *pdev = to_platform_device(shdev->common.dev);
1070 struct sh_dmae_chan *new_sh_chan;
1073 new_sh_chan = kzalloc(sizeof(struct sh_dmae_chan), GFP_KERNEL);
1075 dev_err(shdev->common.dev,
1076 "No free memory for allocating dma channels!\n");
1080 new_sh_chan->pm_state = DMAE_PM_ESTABLISHED;
1082 /* reference struct dma_device */
1083 new_sh_chan->common.device = &shdev->common;
1085 new_sh_chan->dev = shdev->common.dev;
1086 new_sh_chan->id = id;
1087 new_sh_chan->irq = irq;
1088 new_sh_chan->base = shdev->chan_reg + chan_pdata->offset / sizeof(u32);
1090 /* Init DMA tasklet */
1091 tasklet_init(&new_sh_chan->tasklet, dmae_do_tasklet,
1092 (unsigned long)new_sh_chan);
1094 spin_lock_init(&new_sh_chan->desc_lock);
1096 /* Init descripter manage list */
1097 INIT_LIST_HEAD(&new_sh_chan->ld_queue);
1098 INIT_LIST_HEAD(&new_sh_chan->ld_free);
1100 /* Add the channel to DMA device channel list */
1101 list_add_tail(&new_sh_chan->common.device_node,
1102 &shdev->common.channels);
1103 shdev->common.chancnt++;
1106 snprintf(new_sh_chan->dev_id, sizeof(new_sh_chan->dev_id),
1107 "sh-dmae%d.%d", pdev->id, new_sh_chan->id);
1109 snprintf(new_sh_chan->dev_id, sizeof(new_sh_chan->dev_id),
1110 "sh-dma%d", new_sh_chan->id);
1112 /* set up channel irq */
1113 err = request_irq(irq, &sh_dmae_interrupt, flags,
1114 new_sh_chan->dev_id, new_sh_chan);
1116 dev_err(shdev->common.dev, "DMA channel %d request_irq error "
1117 "with return %d\n", id, err);
1121 shdev->chan[id] = new_sh_chan;
1125 /* remove from dmaengine device node */
1126 list_del(&new_sh_chan->common.device_node);
1131 static void sh_dmae_chan_remove(struct sh_dmae_device *shdev)
1135 for (i = shdev->common.chancnt - 1 ; i >= 0 ; i--) {
1136 if (shdev->chan[i]) {
1137 struct sh_dmae_chan *sh_chan = shdev->chan[i];
1139 free_irq(sh_chan->irq, sh_chan);
1141 list_del(&sh_chan->common.device_node);
1143 shdev->chan[i] = NULL;
1146 shdev->common.chancnt = 0;
1149 static int __init sh_dmae_probe(struct platform_device *pdev)
1151 struct sh_dmae_pdata *pdata = pdev->dev.platform_data;
1152 unsigned long irqflags = IRQF_DISABLED,
1153 chan_flag[SH_DMAC_MAX_CHANNELS] = {};
1154 int errirq, chan_irq[SH_DMAC_MAX_CHANNELS];
1155 int err, i, irq_cnt = 0, irqres = 0, irq_cap = 0;
1156 struct sh_dmae_device *shdev;
1157 struct resource *chan, *dmars, *errirq_res, *chanirq_res;
1159 /* get platform data */
1160 if (!pdata || !pdata->channel_num)
1163 chan = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1164 /* DMARS area is optional */
1165 dmars = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1168 * 1. there always must be at least one IRQ IO-resource. On SH4 it is
1169 * the error IRQ, in which case it is the only IRQ in this resource:
1170 * start == end. If it is the only IRQ resource, all channels also
1172 * 2. DMA channel IRQ resources can be specified one per resource or in
1173 * ranges (start != end)
1174 * 3. iff all events (channels and, optionally, error) on this
1175 * controller use the same IRQ, only one IRQ resource can be
1176 * specified, otherwise there must be one IRQ per channel, even if
1177 * some of them are equal
1178 * 4. if all IRQs on this controller are equal or if some specific IRQs
1179 * specify IORESOURCE_IRQ_SHAREABLE in their resources, they will be
1180 * requested with the IRQF_SHARED flag
1182 errirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1183 if (!chan || !errirq_res)
1186 if (!request_mem_region(chan->start, resource_size(chan), pdev->name)) {
1187 dev_err(&pdev->dev, "DMAC register region already claimed\n");
1191 if (dmars && !request_mem_region(dmars->start, resource_size(dmars), pdev->name)) {
1192 dev_err(&pdev->dev, "DMAC DMARS region already claimed\n");
1198 shdev = kzalloc(sizeof(struct sh_dmae_device), GFP_KERNEL);
1200 dev_err(&pdev->dev, "Not enough memory\n");
1204 shdev->chan_reg = ioremap(chan->start, resource_size(chan));
1205 if (!shdev->chan_reg)
1208 shdev->dmars = ioremap(dmars->start, resource_size(dmars));
1214 shdev->pdata = pdata;
1216 if (pdata->chcr_offset)
1217 shdev->chcr_offset = pdata->chcr_offset;
1219 shdev->chcr_offset = CHCR;
1221 if (pdata->chcr_ie_bit)
1222 shdev->chcr_ie_bit = pdata->chcr_ie_bit;
1224 shdev->chcr_ie_bit = CHCR_IE;
1226 platform_set_drvdata(pdev, shdev);
1228 pm_runtime_enable(&pdev->dev);
1229 pm_runtime_get_sync(&pdev->dev);
1231 spin_lock_irq(&sh_dmae_lock);
1232 list_add_tail_rcu(&shdev->node, &sh_dmae_devices);
1233 spin_unlock_irq(&sh_dmae_lock);
1235 /* reset dma controller - only needed as a test */
1236 err = sh_dmae_rst(shdev);
1240 INIT_LIST_HEAD(&shdev->common.channels);
1242 dma_cap_set(DMA_MEMCPY, shdev->common.cap_mask);
1243 if (pdata->slave && pdata->slave_num)
1244 dma_cap_set(DMA_SLAVE, shdev->common.cap_mask);
1246 shdev->common.device_alloc_chan_resources
1247 = sh_dmae_alloc_chan_resources;
1248 shdev->common.device_free_chan_resources = sh_dmae_free_chan_resources;
1249 shdev->common.device_prep_dma_memcpy = sh_dmae_prep_memcpy;
1250 shdev->common.device_tx_status = sh_dmae_tx_status;
1251 shdev->common.device_issue_pending = sh_dmae_memcpy_issue_pending;
1253 /* Compulsory for DMA_SLAVE fields */
1254 shdev->common.device_prep_slave_sg = sh_dmae_prep_slave_sg;
1255 shdev->common.device_control = sh_dmae_control;
1257 shdev->common.dev = &pdev->dev;
1258 /* Default transfer size of 32 bytes requires 32-byte alignment */
1259 shdev->common.copy_align = LOG2_DEFAULT_XFER_SIZE;
1261 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARCH_SHMOBILE)
1262 chanirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
1265 chanirq_res = errirq_res;
1269 if (chanirq_res == errirq_res ||
1270 (errirq_res->flags & IORESOURCE_BITS) == IORESOURCE_IRQ_SHAREABLE)
1271 irqflags = IRQF_SHARED;
1273 errirq = errirq_res->start;
1275 err = request_irq(errirq, sh_dmae_err, irqflags,
1276 "DMAC Address Error", shdev);
1279 "DMA failed requesting irq #%d, error %d\n",
1285 chanirq_res = errirq_res;
1286 #endif /* CONFIG_CPU_SH4 || CONFIG_ARCH_SHMOBILE */
1288 if (chanirq_res->start == chanirq_res->end &&
1289 !platform_get_resource(pdev, IORESOURCE_IRQ, 1)) {
1290 /* Special case - all multiplexed */
1291 for (; irq_cnt < pdata->channel_num; irq_cnt++) {
1292 if (irq_cnt < SH_DMAC_MAX_CHANNELS) {
1293 chan_irq[irq_cnt] = chanirq_res->start;
1294 chan_flag[irq_cnt] = IRQF_SHARED;
1302 for (i = chanirq_res->start; i <= chanirq_res->end; i++) {
1303 if (irq_cnt >= SH_DMAC_MAX_CHANNELS) {
1308 if ((errirq_res->flags & IORESOURCE_BITS) ==
1309 IORESOURCE_IRQ_SHAREABLE)
1310 chan_flag[irq_cnt] = IRQF_SHARED;
1312 chan_flag[irq_cnt] = IRQF_DISABLED;
1314 "Found IRQ %d for channel %d\n",
1316 chan_irq[irq_cnt++] = i;
1319 if (irq_cnt >= SH_DMAC_MAX_CHANNELS)
1322 chanirq_res = platform_get_resource(pdev,
1323 IORESOURCE_IRQ, ++irqres);
1324 } while (irq_cnt < pdata->channel_num && chanirq_res);
1327 /* Create DMA Channel */
1328 for (i = 0; i < irq_cnt; i++) {
1329 err = sh_dmae_chan_probe(shdev, i, chan_irq[i], chan_flag[i]);
1331 goto chan_probe_err;
1335 dev_notice(&pdev->dev, "Attempting to register %d DMA "
1336 "channels when a maximum of %d are supported.\n",
1337 pdata->channel_num, SH_DMAC_MAX_CHANNELS);
1339 pm_runtime_put(&pdev->dev);
1341 dma_async_device_register(&shdev->common);
1346 sh_dmae_chan_remove(shdev);
1348 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARCH_SHMOBILE)
1349 free_irq(errirq, shdev);
1353 spin_lock_irq(&sh_dmae_lock);
1354 list_del_rcu(&shdev->node);
1355 spin_unlock_irq(&sh_dmae_lock);
1357 pm_runtime_put(&pdev->dev);
1358 pm_runtime_disable(&pdev->dev);
1361 iounmap(shdev->dmars);
1363 platform_set_drvdata(pdev, NULL);
1365 iounmap(shdev->chan_reg);
1371 release_mem_region(dmars->start, resource_size(dmars));
1373 release_mem_region(chan->start, resource_size(chan));
1378 static int __exit sh_dmae_remove(struct platform_device *pdev)
1380 struct sh_dmae_device *shdev = platform_get_drvdata(pdev);
1381 struct resource *res;
1382 int errirq = platform_get_irq(pdev, 0);
1384 dma_async_device_unregister(&shdev->common);
1387 free_irq(errirq, shdev);
1389 spin_lock_irq(&sh_dmae_lock);
1390 list_del_rcu(&shdev->node);
1391 spin_unlock_irq(&sh_dmae_lock);
1393 /* channel data remove */
1394 sh_dmae_chan_remove(shdev);
1396 pm_runtime_disable(&pdev->dev);
1399 iounmap(shdev->dmars);
1400 iounmap(shdev->chan_reg);
1402 platform_set_drvdata(pdev, NULL);
1407 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1409 release_mem_region(res->start, resource_size(res));
1410 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1412 release_mem_region(res->start, resource_size(res));
1417 static void sh_dmae_shutdown(struct platform_device *pdev)
1419 struct sh_dmae_device *shdev = platform_get_drvdata(pdev);
1420 sh_dmae_ctl_stop(shdev);
1423 static int sh_dmae_runtime_suspend(struct device *dev)
1428 static int sh_dmae_runtime_resume(struct device *dev)
1430 struct sh_dmae_device *shdev = dev_get_drvdata(dev);
1432 return sh_dmae_rst(shdev);
1436 static int sh_dmae_suspend(struct device *dev)
1438 struct sh_dmae_device *shdev = dev_get_drvdata(dev);
1441 for (i = 0; i < shdev->pdata->channel_num; i++) {
1442 struct sh_dmae_chan *sh_chan = shdev->chan[i];
1443 if (sh_chan->descs_allocated)
1444 sh_chan->pm_error = pm_runtime_put_sync(dev);
1450 static int sh_dmae_resume(struct device *dev)
1452 struct sh_dmae_device *shdev = dev_get_drvdata(dev);
1455 for (i = 0; i < shdev->pdata->channel_num; i++) {
1456 struct sh_dmae_chan *sh_chan = shdev->chan[i];
1457 struct sh_dmae_slave *param = sh_chan->common.private;
1459 if (!sh_chan->descs_allocated)
1462 if (!sh_chan->pm_error)
1463 pm_runtime_get_sync(dev);
1466 const struct sh_dmae_slave_config *cfg = param->config;
1467 dmae_set_dmars(sh_chan, cfg->mid_rid);
1468 dmae_set_chcr(sh_chan, cfg->chcr);
1477 #define sh_dmae_suspend NULL
1478 #define sh_dmae_resume NULL
1481 const struct dev_pm_ops sh_dmae_pm = {
1482 .suspend = sh_dmae_suspend,
1483 .resume = sh_dmae_resume,
1484 .runtime_suspend = sh_dmae_runtime_suspend,
1485 .runtime_resume = sh_dmae_runtime_resume,
1488 static struct platform_driver sh_dmae_driver = {
1489 .remove = __exit_p(sh_dmae_remove),
1490 .shutdown = sh_dmae_shutdown,
1492 .owner = THIS_MODULE,
1493 .name = "sh-dma-engine",
1498 static int __init sh_dmae_init(void)
1500 /* Wire up NMI handling */
1501 int err = register_die_notifier(&sh_dmae_nmi_notifier);
1505 return platform_driver_probe(&sh_dmae_driver, sh_dmae_probe);
1507 module_init(sh_dmae_init);
1509 static void __exit sh_dmae_exit(void)
1511 platform_driver_unregister(&sh_dmae_driver);
1513 unregister_die_notifier(&sh_dmae_nmi_notifier);
1515 module_exit(sh_dmae_exit);
1517 MODULE_AUTHOR("Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>");
1518 MODULE_DESCRIPTION("Renesas SH DMA Engine driver");
1519 MODULE_LICENSE("GPL");
1520 MODULE_ALIAS("platform:sh-dma-engine");