WIP FPC-III support
[linux/fpc-iii.git] / drivers / dma / idma64.c
blobf4c07ad3be15b427a43b7c9a60e4e5d43f9a9fa2
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Core driver for the Intel integrated DMA 64-bit
5 * Copyright (C) 2015 Intel Corporation
6 * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
7 */
9 #include <linux/bitops.h>
10 #include <linux/delay.h>
11 #include <linux/dmaengine.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/dmapool.h>
14 #include <linux/init.h>
15 #include <linux/module.h>
16 #include <linux/platform_device.h>
17 #include <linux/slab.h>
19 #include <linux/dma/idma64.h>
21 #include "idma64.h"
23 /* For now we support only two channels */
24 #define IDMA64_NR_CHAN 2
26 /* ---------------------------------------------------------------------- */
28 static struct device *chan2dev(struct dma_chan *chan)
30 return &chan->dev->device;
33 /* ---------------------------------------------------------------------- */
35 static void idma64_off(struct idma64 *idma64)
37 unsigned short count = 100;
39 dma_writel(idma64, CFG, 0);
41 channel_clear_bit(idma64, MASK(XFER), idma64->all_chan_mask);
42 channel_clear_bit(idma64, MASK(BLOCK), idma64->all_chan_mask);
43 channel_clear_bit(idma64, MASK(SRC_TRAN), idma64->all_chan_mask);
44 channel_clear_bit(idma64, MASK(DST_TRAN), idma64->all_chan_mask);
45 channel_clear_bit(idma64, MASK(ERROR), idma64->all_chan_mask);
47 do {
48 cpu_relax();
49 } while (dma_readl(idma64, CFG) & IDMA64_CFG_DMA_EN && --count);
52 static void idma64_on(struct idma64 *idma64)
54 dma_writel(idma64, CFG, IDMA64_CFG_DMA_EN);
57 /* ---------------------------------------------------------------------- */
59 static void idma64_chan_init(struct idma64 *idma64, struct idma64_chan *idma64c)
61 u32 cfghi = IDMA64C_CFGH_SRC_PER(1) | IDMA64C_CFGH_DST_PER(0);
62 u32 cfglo = 0;
64 /* Set default burst alignment */
65 cfglo |= IDMA64C_CFGL_DST_BURST_ALIGN | IDMA64C_CFGL_SRC_BURST_ALIGN;
67 channel_writel(idma64c, CFG_LO, cfglo);
68 channel_writel(idma64c, CFG_HI, cfghi);
70 /* Enable interrupts */
71 channel_set_bit(idma64, MASK(XFER), idma64c->mask);
72 channel_set_bit(idma64, MASK(ERROR), idma64c->mask);
75 * Enforce the controller to be turned on.
77 * The iDMA is turned off in ->probe() and looses context during system
78 * suspend / resume cycle. That's why we have to enable it each time we
79 * use it.
81 idma64_on(idma64);
84 static void idma64_chan_stop(struct idma64 *idma64, struct idma64_chan *idma64c)
86 channel_clear_bit(idma64, CH_EN, idma64c->mask);
89 static void idma64_chan_start(struct idma64 *idma64, struct idma64_chan *idma64c)
91 struct idma64_desc *desc = idma64c->desc;
92 struct idma64_hw_desc *hw = &desc->hw[0];
94 channel_writeq(idma64c, SAR, 0);
95 channel_writeq(idma64c, DAR, 0);
97 channel_writel(idma64c, CTL_HI, IDMA64C_CTLH_BLOCK_TS(~0UL));
98 channel_writel(idma64c, CTL_LO, IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN);
100 channel_writeq(idma64c, LLP, hw->llp);
102 channel_set_bit(idma64, CH_EN, idma64c->mask);
105 static void idma64_stop_transfer(struct idma64_chan *idma64c)
107 struct idma64 *idma64 = to_idma64(idma64c->vchan.chan.device);
109 idma64_chan_stop(idma64, idma64c);
112 static void idma64_start_transfer(struct idma64_chan *idma64c)
114 struct idma64 *idma64 = to_idma64(idma64c->vchan.chan.device);
115 struct virt_dma_desc *vdesc;
117 /* Get the next descriptor */
118 vdesc = vchan_next_desc(&idma64c->vchan);
119 if (!vdesc) {
120 idma64c->desc = NULL;
121 return;
124 list_del(&vdesc->node);
125 idma64c->desc = to_idma64_desc(vdesc);
127 /* Configure the channel */
128 idma64_chan_init(idma64, idma64c);
130 /* Start the channel with a new descriptor */
131 idma64_chan_start(idma64, idma64c);
134 /* ---------------------------------------------------------------------- */
136 static void idma64_chan_irq(struct idma64 *idma64, unsigned short c,
137 u32 status_err, u32 status_xfer)
139 struct idma64_chan *idma64c = &idma64->chan[c];
140 struct idma64_desc *desc;
142 spin_lock(&idma64c->vchan.lock);
143 desc = idma64c->desc;
144 if (desc) {
145 if (status_err & (1 << c)) {
146 dma_writel(idma64, CLEAR(ERROR), idma64c->mask);
147 desc->status = DMA_ERROR;
148 } else if (status_xfer & (1 << c)) {
149 dma_writel(idma64, CLEAR(XFER), idma64c->mask);
150 desc->status = DMA_COMPLETE;
151 vchan_cookie_complete(&desc->vdesc);
152 idma64_start_transfer(idma64c);
155 /* idma64_start_transfer() updates idma64c->desc */
156 if (idma64c->desc == NULL || desc->status == DMA_ERROR)
157 idma64_stop_transfer(idma64c);
159 spin_unlock(&idma64c->vchan.lock);
162 static irqreturn_t idma64_irq(int irq, void *dev)
164 struct idma64 *idma64 = dev;
165 u32 status = dma_readl(idma64, STATUS_INT);
166 u32 status_xfer;
167 u32 status_err;
168 unsigned short i;
170 dev_vdbg(idma64->dma.dev, "%s: status=%#x\n", __func__, status);
172 /* Check if we have any interrupt from the DMA controller */
173 if (!status)
174 return IRQ_NONE;
176 status_xfer = dma_readl(idma64, RAW(XFER));
177 status_err = dma_readl(idma64, RAW(ERROR));
179 for (i = 0; i < idma64->dma.chancnt; i++)
180 idma64_chan_irq(idma64, i, status_err, status_xfer);
182 return IRQ_HANDLED;
185 /* ---------------------------------------------------------------------- */
187 static struct idma64_desc *idma64_alloc_desc(unsigned int ndesc)
189 struct idma64_desc *desc;
191 desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
192 if (!desc)
193 return NULL;
195 desc->hw = kcalloc(ndesc, sizeof(*desc->hw), GFP_NOWAIT);
196 if (!desc->hw) {
197 kfree(desc);
198 return NULL;
201 return desc;
204 static void idma64_desc_free(struct idma64_chan *idma64c,
205 struct idma64_desc *desc)
207 struct idma64_hw_desc *hw;
209 if (desc->ndesc) {
210 unsigned int i = desc->ndesc;
212 do {
213 hw = &desc->hw[--i];
214 dma_pool_free(idma64c->pool, hw->lli, hw->llp);
215 } while (i);
218 kfree(desc->hw);
219 kfree(desc);
222 static void idma64_vdesc_free(struct virt_dma_desc *vdesc)
224 struct idma64_chan *idma64c = to_idma64_chan(vdesc->tx.chan);
226 idma64_desc_free(idma64c, to_idma64_desc(vdesc));
229 static void idma64_hw_desc_fill(struct idma64_hw_desc *hw,
230 struct dma_slave_config *config,
231 enum dma_transfer_direction direction, u64 llp)
233 struct idma64_lli *lli = hw->lli;
234 u64 sar, dar;
235 u32 ctlhi = IDMA64C_CTLH_BLOCK_TS(hw->len);
236 u32 ctllo = IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN;
237 u32 src_width, dst_width;
239 if (direction == DMA_MEM_TO_DEV) {
240 sar = hw->phys;
241 dar = config->dst_addr;
242 ctllo |= IDMA64C_CTLL_DST_FIX | IDMA64C_CTLL_SRC_INC |
243 IDMA64C_CTLL_FC_M2P;
244 src_width = __ffs(sar | hw->len | 4);
245 dst_width = __ffs(config->dst_addr_width);
246 } else { /* DMA_DEV_TO_MEM */
247 sar = config->src_addr;
248 dar = hw->phys;
249 ctllo |= IDMA64C_CTLL_DST_INC | IDMA64C_CTLL_SRC_FIX |
250 IDMA64C_CTLL_FC_P2M;
251 src_width = __ffs(config->src_addr_width);
252 dst_width = __ffs(dar | hw->len | 4);
255 lli->sar = sar;
256 lli->dar = dar;
258 lli->ctlhi = ctlhi;
259 lli->ctllo = ctllo |
260 IDMA64C_CTLL_SRC_MSIZE(config->src_maxburst) |
261 IDMA64C_CTLL_DST_MSIZE(config->dst_maxburst) |
262 IDMA64C_CTLL_DST_WIDTH(dst_width) |
263 IDMA64C_CTLL_SRC_WIDTH(src_width);
265 lli->llp = llp;
268 static void idma64_desc_fill(struct idma64_chan *idma64c,
269 struct idma64_desc *desc)
271 struct dma_slave_config *config = &idma64c->config;
272 unsigned int i = desc->ndesc;
273 struct idma64_hw_desc *hw = &desc->hw[i - 1];
274 struct idma64_lli *lli = hw->lli;
275 u64 llp = 0;
277 /* Fill the hardware descriptors and link them to a list */
278 do {
279 hw = &desc->hw[--i];
280 idma64_hw_desc_fill(hw, config, desc->direction, llp);
281 llp = hw->llp;
282 desc->length += hw->len;
283 } while (i);
285 /* Trigger an interrupt after the last block is transfered */
286 lli->ctllo |= IDMA64C_CTLL_INT_EN;
288 /* Disable LLP transfer in the last block */
289 lli->ctllo &= ~(IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN);
292 static struct dma_async_tx_descriptor *idma64_prep_slave_sg(
293 struct dma_chan *chan, struct scatterlist *sgl,
294 unsigned int sg_len, enum dma_transfer_direction direction,
295 unsigned long flags, void *context)
297 struct idma64_chan *idma64c = to_idma64_chan(chan);
298 struct idma64_desc *desc;
299 struct scatterlist *sg;
300 unsigned int i;
302 desc = idma64_alloc_desc(sg_len);
303 if (!desc)
304 return NULL;
306 for_each_sg(sgl, sg, sg_len, i) {
307 struct idma64_hw_desc *hw = &desc->hw[i];
309 /* Allocate DMA capable memory for hardware descriptor */
310 hw->lli = dma_pool_alloc(idma64c->pool, GFP_NOWAIT, &hw->llp);
311 if (!hw->lli) {
312 desc->ndesc = i;
313 idma64_desc_free(idma64c, desc);
314 return NULL;
317 hw->phys = sg_dma_address(sg);
318 hw->len = sg_dma_len(sg);
321 desc->ndesc = sg_len;
322 desc->direction = direction;
323 desc->status = DMA_IN_PROGRESS;
325 idma64_desc_fill(idma64c, desc);
326 return vchan_tx_prep(&idma64c->vchan, &desc->vdesc, flags);
329 static void idma64_issue_pending(struct dma_chan *chan)
331 struct idma64_chan *idma64c = to_idma64_chan(chan);
332 unsigned long flags;
334 spin_lock_irqsave(&idma64c->vchan.lock, flags);
335 if (vchan_issue_pending(&idma64c->vchan) && !idma64c->desc)
336 idma64_start_transfer(idma64c);
337 spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
340 static size_t idma64_active_desc_size(struct idma64_chan *idma64c)
342 struct idma64_desc *desc = idma64c->desc;
343 struct idma64_hw_desc *hw;
344 size_t bytes = desc->length;
345 u64 llp = channel_readq(idma64c, LLP);
346 u32 ctlhi = channel_readl(idma64c, CTL_HI);
347 unsigned int i = 0;
349 do {
350 hw = &desc->hw[i];
351 if (hw->llp == llp)
352 break;
353 bytes -= hw->len;
354 } while (++i < desc->ndesc);
356 if (!i)
357 return bytes;
359 /* The current chunk is not fully transfered yet */
360 bytes += desc->hw[--i].len;
362 return bytes - IDMA64C_CTLH_BLOCK_TS(ctlhi);
365 static enum dma_status idma64_tx_status(struct dma_chan *chan,
366 dma_cookie_t cookie, struct dma_tx_state *state)
368 struct idma64_chan *idma64c = to_idma64_chan(chan);
369 struct virt_dma_desc *vdesc;
370 enum dma_status status;
371 size_t bytes;
372 unsigned long flags;
374 status = dma_cookie_status(chan, cookie, state);
375 if (status == DMA_COMPLETE)
376 return status;
378 spin_lock_irqsave(&idma64c->vchan.lock, flags);
379 vdesc = vchan_find_desc(&idma64c->vchan, cookie);
380 if (idma64c->desc && cookie == idma64c->desc->vdesc.tx.cookie) {
381 bytes = idma64_active_desc_size(idma64c);
382 dma_set_residue(state, bytes);
383 status = idma64c->desc->status;
384 } else if (vdesc) {
385 bytes = to_idma64_desc(vdesc)->length;
386 dma_set_residue(state, bytes);
388 spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
390 return status;
393 static void convert_burst(u32 *maxburst)
395 if (*maxburst)
396 *maxburst = __fls(*maxburst);
397 else
398 *maxburst = 0;
401 static int idma64_slave_config(struct dma_chan *chan,
402 struct dma_slave_config *config)
404 struct idma64_chan *idma64c = to_idma64_chan(chan);
406 memcpy(&idma64c->config, config, sizeof(idma64c->config));
408 convert_burst(&idma64c->config.src_maxburst);
409 convert_burst(&idma64c->config.dst_maxburst);
411 return 0;
414 static void idma64_chan_deactivate(struct idma64_chan *idma64c, bool drain)
416 unsigned short count = 100;
417 u32 cfglo;
419 cfglo = channel_readl(idma64c, CFG_LO);
420 if (drain)
421 cfglo |= IDMA64C_CFGL_CH_DRAIN;
422 else
423 cfglo &= ~IDMA64C_CFGL_CH_DRAIN;
425 channel_writel(idma64c, CFG_LO, cfglo | IDMA64C_CFGL_CH_SUSP);
426 do {
427 udelay(1);
428 cfglo = channel_readl(idma64c, CFG_LO);
429 } while (!(cfglo & IDMA64C_CFGL_FIFO_EMPTY) && --count);
432 static void idma64_chan_activate(struct idma64_chan *idma64c)
434 u32 cfglo;
436 cfglo = channel_readl(idma64c, CFG_LO);
437 channel_writel(idma64c, CFG_LO, cfglo & ~IDMA64C_CFGL_CH_SUSP);
440 static int idma64_pause(struct dma_chan *chan)
442 struct idma64_chan *idma64c = to_idma64_chan(chan);
443 unsigned long flags;
445 spin_lock_irqsave(&idma64c->vchan.lock, flags);
446 if (idma64c->desc && idma64c->desc->status == DMA_IN_PROGRESS) {
447 idma64_chan_deactivate(idma64c, false);
448 idma64c->desc->status = DMA_PAUSED;
450 spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
452 return 0;
455 static int idma64_resume(struct dma_chan *chan)
457 struct idma64_chan *idma64c = to_idma64_chan(chan);
458 unsigned long flags;
460 spin_lock_irqsave(&idma64c->vchan.lock, flags);
461 if (idma64c->desc && idma64c->desc->status == DMA_PAUSED) {
462 idma64c->desc->status = DMA_IN_PROGRESS;
463 idma64_chan_activate(idma64c);
465 spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
467 return 0;
470 static int idma64_terminate_all(struct dma_chan *chan)
472 struct idma64_chan *idma64c = to_idma64_chan(chan);
473 unsigned long flags;
474 LIST_HEAD(head);
476 spin_lock_irqsave(&idma64c->vchan.lock, flags);
477 idma64_chan_deactivate(idma64c, true);
478 idma64_stop_transfer(idma64c);
479 if (idma64c->desc) {
480 idma64_vdesc_free(&idma64c->desc->vdesc);
481 idma64c->desc = NULL;
483 vchan_get_all_descriptors(&idma64c->vchan, &head);
484 spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
486 vchan_dma_desc_free_list(&idma64c->vchan, &head);
487 return 0;
490 static void idma64_synchronize(struct dma_chan *chan)
492 struct idma64_chan *idma64c = to_idma64_chan(chan);
494 vchan_synchronize(&idma64c->vchan);
497 static int idma64_alloc_chan_resources(struct dma_chan *chan)
499 struct idma64_chan *idma64c = to_idma64_chan(chan);
501 /* Create a pool of consistent memory blocks for hardware descriptors */
502 idma64c->pool = dma_pool_create(dev_name(chan2dev(chan)),
503 chan->device->dev,
504 sizeof(struct idma64_lli), 8, 0);
505 if (!idma64c->pool) {
506 dev_err(chan2dev(chan), "No memory for descriptors\n");
507 return -ENOMEM;
510 return 0;
513 static void idma64_free_chan_resources(struct dma_chan *chan)
515 struct idma64_chan *idma64c = to_idma64_chan(chan);
517 vchan_free_chan_resources(to_virt_chan(chan));
518 dma_pool_destroy(idma64c->pool);
519 idma64c->pool = NULL;
522 /* ---------------------------------------------------------------------- */
524 #define IDMA64_BUSWIDTHS \
525 BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
526 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
527 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)
529 static int idma64_probe(struct idma64_chip *chip)
531 struct idma64 *idma64;
532 unsigned short nr_chan = IDMA64_NR_CHAN;
533 unsigned short i;
534 int ret;
536 idma64 = devm_kzalloc(chip->dev, sizeof(*idma64), GFP_KERNEL);
537 if (!idma64)
538 return -ENOMEM;
540 idma64->regs = chip->regs;
541 chip->idma64 = idma64;
543 idma64->chan = devm_kcalloc(chip->dev, nr_chan, sizeof(*idma64->chan),
544 GFP_KERNEL);
545 if (!idma64->chan)
546 return -ENOMEM;
548 idma64->all_chan_mask = (1 << nr_chan) - 1;
550 /* Turn off iDMA controller */
551 idma64_off(idma64);
553 ret = devm_request_irq(chip->dev, chip->irq, idma64_irq, IRQF_SHARED,
554 dev_name(chip->dev), idma64);
555 if (ret)
556 return ret;
558 INIT_LIST_HEAD(&idma64->dma.channels);
559 for (i = 0; i < nr_chan; i++) {
560 struct idma64_chan *idma64c = &idma64->chan[i];
562 idma64c->vchan.desc_free = idma64_vdesc_free;
563 vchan_init(&idma64c->vchan, &idma64->dma);
565 idma64c->regs = idma64->regs + i * IDMA64_CH_LENGTH;
566 idma64c->mask = BIT(i);
569 dma_cap_set(DMA_SLAVE, idma64->dma.cap_mask);
570 dma_cap_set(DMA_PRIVATE, idma64->dma.cap_mask);
572 idma64->dma.device_alloc_chan_resources = idma64_alloc_chan_resources;
573 idma64->dma.device_free_chan_resources = idma64_free_chan_resources;
575 idma64->dma.device_prep_slave_sg = idma64_prep_slave_sg;
577 idma64->dma.device_issue_pending = idma64_issue_pending;
578 idma64->dma.device_tx_status = idma64_tx_status;
580 idma64->dma.device_config = idma64_slave_config;
581 idma64->dma.device_pause = idma64_pause;
582 idma64->dma.device_resume = idma64_resume;
583 idma64->dma.device_terminate_all = idma64_terminate_all;
584 idma64->dma.device_synchronize = idma64_synchronize;
586 idma64->dma.src_addr_widths = IDMA64_BUSWIDTHS;
587 idma64->dma.dst_addr_widths = IDMA64_BUSWIDTHS;
588 idma64->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
589 idma64->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
591 idma64->dma.dev = chip->sysdev;
593 dma_set_max_seg_size(idma64->dma.dev, IDMA64C_CTLH_BLOCK_TS_MASK);
595 ret = dma_async_device_register(&idma64->dma);
596 if (ret)
597 return ret;
599 dev_info(chip->dev, "Found Intel integrated DMA 64-bit\n");
600 return 0;
603 static int idma64_remove(struct idma64_chip *chip)
605 struct idma64 *idma64 = chip->idma64;
606 unsigned short i;
608 dma_async_device_unregister(&idma64->dma);
611 * Explicitly call devm_request_irq() to avoid the side effects with
612 * the scheduled tasklets.
614 devm_free_irq(chip->dev, chip->irq, idma64);
616 for (i = 0; i < idma64->dma.chancnt; i++) {
617 struct idma64_chan *idma64c = &idma64->chan[i];
619 tasklet_kill(&idma64c->vchan.task);
622 return 0;
625 /* ---------------------------------------------------------------------- */
627 static int idma64_platform_probe(struct platform_device *pdev)
629 struct idma64_chip *chip;
630 struct device *dev = &pdev->dev;
631 struct device *sysdev = dev->parent;
632 struct resource *mem;
633 int ret;
635 chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
636 if (!chip)
637 return -ENOMEM;
639 chip->irq = platform_get_irq(pdev, 0);
640 if (chip->irq < 0)
641 return chip->irq;
643 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
644 chip->regs = devm_ioremap_resource(dev, mem);
645 if (IS_ERR(chip->regs))
646 return PTR_ERR(chip->regs);
648 ret = dma_coerce_mask_and_coherent(sysdev, DMA_BIT_MASK(64));
649 if (ret)
650 return ret;
652 chip->dev = dev;
653 chip->sysdev = sysdev;
655 ret = idma64_probe(chip);
656 if (ret)
657 return ret;
659 platform_set_drvdata(pdev, chip);
660 return 0;
663 static int idma64_platform_remove(struct platform_device *pdev)
665 struct idma64_chip *chip = platform_get_drvdata(pdev);
667 return idma64_remove(chip);
670 static int __maybe_unused idma64_pm_suspend(struct device *dev)
672 struct idma64_chip *chip = dev_get_drvdata(dev);
674 idma64_off(chip->idma64);
675 return 0;
678 static int __maybe_unused idma64_pm_resume(struct device *dev)
680 struct idma64_chip *chip = dev_get_drvdata(dev);
682 idma64_on(chip->idma64);
683 return 0;
686 static const struct dev_pm_ops idma64_dev_pm_ops = {
687 SET_SYSTEM_SLEEP_PM_OPS(idma64_pm_suspend, idma64_pm_resume)
690 static struct platform_driver idma64_platform_driver = {
691 .probe = idma64_platform_probe,
692 .remove = idma64_platform_remove,
693 .driver = {
694 .name = LPSS_IDMA64_DRIVER_NAME,
695 .pm = &idma64_dev_pm_ops,
699 module_platform_driver(idma64_platform_driver);
701 MODULE_LICENSE("GPL v2");
702 MODULE_DESCRIPTION("iDMA64 core driver");
703 MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
704 MODULE_ALIAS("platform:" LPSS_IDMA64_DRIVER_NAME);