brintos

brintos / linux-shallow public Read only

0
0
Text · 24.2 KiB · b69eabf Raw
936 lines · c
1// SPDX-License-Identifier: GPL-2.02// Copyright (c) 2018-2019 MediaTek Inc.3 4/*5 * Driver for MediaTek Command-Queue DMA Controller6 *7 * Author: Shun-Chih Yu <shun-chih.yu@mediatek.com>8 *9 */10 11#include <linux/bitops.h>12#include <linux/clk.h>13#include <linux/dmaengine.h>14#include <linux/dma-mapping.h>15#include <linux/err.h>16#include <linux/iopoll.h>17#include <linux/interrupt.h>18#include <linux/list.h>19#include <linux/module.h>20#include <linux/of.h>21#include <linux/of_dma.h>22#include <linux/platform_device.h>23#include <linux/pm_runtime.h>24#include <linux/refcount.h>25#include <linux/slab.h>26 27#include "../virt-dma.h"28 29#define MTK_CQDMA_USEC_POLL		1030#define MTK_CQDMA_TIMEOUT_POLL		100031#define MTK_CQDMA_DMA_BUSWIDTHS		BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)32#define MTK_CQDMA_ALIGN_SIZE		133 34/* The default number of virtual channel */35#define MTK_CQDMA_NR_VCHANS		3236 37/* The default number of physical channel */38#define MTK_CQDMA_NR_PCHANS		339 40/* Registers for underlying dma manipulation */41#define MTK_CQDMA_INT_FLAG		0x042#define MTK_CQDMA_INT_EN		0x443#define MTK_CQDMA_EN			0x844#define MTK_CQDMA_RESET			0xc45#define MTK_CQDMA_FLUSH			0x1446#define MTK_CQDMA_SRC			0x1c47#define MTK_CQDMA_DST			0x2048#define MTK_CQDMA_LEN1			0x2449#define MTK_CQDMA_LEN2			0x2850#define MTK_CQDMA_SRC2			0x6051#define MTK_CQDMA_DST2			0x6452 53/* Registers setting */54#define MTK_CQDMA_EN_BIT		BIT(0)55#define MTK_CQDMA_INT_FLAG_BIT		BIT(0)56#define MTK_CQDMA_INT_EN_BIT		BIT(0)57#define MTK_CQDMA_FLUSH_BIT		BIT(0)58 59#define MTK_CQDMA_WARM_RST_BIT		BIT(0)60#define MTK_CQDMA_HARD_RST_BIT		BIT(1)61 62#define MTK_CQDMA_MAX_LEN		GENMASK(27, 0)63#define MTK_CQDMA_ADDR_LIMIT		GENMASK(31, 0)64#define MTK_CQDMA_ADDR2_SHFIT		(32)65 66/**67 * struct mtk_cqdma_vdesc - The struct holding info describing virtual68 *                         descriptor (CVD)69 * @vd:                    An instance for struct virt_dma_desc70 * @len:                   The total data size device wants to move71 * @residue:               The remaining data size device will move72 * @dest:                  The destination address device wants to move to73 * @src:                   The source address device wants to move from74 * @ch:                    The pointer to the corresponding dma channel75 * @node:                  The lise_head struct to build link-list for VDs76 * @parent:                The pointer to the parent CVD77 */78struct mtk_cqdma_vdesc {79	struct virt_dma_desc vd;80	size_t len;81	size_t residue;82	dma_addr_t dest;83	dma_addr_t src;84	struct dma_chan *ch;85 86	struct list_head node;87	struct mtk_cqdma_vdesc *parent;88};89 90/**91 * struct mtk_cqdma_pchan - The struct holding info describing physical92 *                         channel (PC)93 * @queue:                 Queue for the PDs issued to this PC94 * @base:                  The mapped register I/O base of this PC95 * @irq:                   The IRQ that this PC are using96 * @refcnt:                Track how many VCs are using this PC97 * @tasklet:               Tasklet for this PC98 * @lock:                  Lock protect agaisting multiple VCs access PC99 */100struct mtk_cqdma_pchan {101	struct list_head queue;102	void __iomem *base;103	u32 irq;104 105	refcount_t refcnt;106 107	struct tasklet_struct tasklet;108 109	/* lock to protect PC */110	spinlock_t lock;111};112 113/**114 * struct mtk_cqdma_vchan - The struct holding info describing virtual115 *                         channel (VC)116 * @vc:                    An instance for struct virt_dma_chan117 * @pc:                    The pointer to the underlying PC118 * @issue_completion:	   The wait for all issued descriptors completited119 * @issue_synchronize:	   Bool indicating channel synchronization starts120 */121struct mtk_cqdma_vchan {122	struct virt_dma_chan vc;123	struct mtk_cqdma_pchan *pc;124	struct completion issue_completion;125	bool issue_synchronize;126};127 128/**129 * struct mtk_cqdma_device - The struct holding info describing CQDMA130 *                          device131 * @ddev:                   An instance for struct dma_device132 * @clk:                    The clock that device internal is using133 * @dma_requests:           The number of VCs the device supports to134 * @dma_channels:           The number of PCs the device supports to135 * @vc:                     The pointer to all available VCs136 * @pc:                     The pointer to all the underlying PCs137 */138struct mtk_cqdma_device {139	struct dma_device ddev;140	struct clk *clk;141 142	u32 dma_requests;143	u32 dma_channels;144	struct mtk_cqdma_vchan *vc;145	struct mtk_cqdma_pchan **pc;146};147 148static struct mtk_cqdma_device *to_cqdma_dev(struct dma_chan *chan)149{150	return container_of(chan->device, struct mtk_cqdma_device, ddev);151}152 153static struct mtk_cqdma_vchan *to_cqdma_vchan(struct dma_chan *chan)154{155	return container_of(chan, struct mtk_cqdma_vchan, vc.chan);156}157 158static struct mtk_cqdma_vdesc *to_cqdma_vdesc(struct virt_dma_desc *vd)159{160	return container_of(vd, struct mtk_cqdma_vdesc, vd);161}162 163static struct device *cqdma2dev(struct mtk_cqdma_device *cqdma)164{165	return cqdma->ddev.dev;166}167 168static u32 mtk_dma_read(struct mtk_cqdma_pchan *pc, u32 reg)169{170	return readl(pc->base + reg);171}172 173static void mtk_dma_write(struct mtk_cqdma_pchan *pc, u32 reg, u32 val)174{175	writel_relaxed(val, pc->base + reg);176}177 178static void mtk_dma_rmw(struct mtk_cqdma_pchan *pc, u32 reg,179			u32 mask, u32 set)180{181	u32 val;182 183	val = mtk_dma_read(pc, reg);184	val &= ~mask;185	val |= set;186	mtk_dma_write(pc, reg, val);187}188 189static void mtk_dma_set(struct mtk_cqdma_pchan *pc, u32 reg, u32 val)190{191	mtk_dma_rmw(pc, reg, 0, val);192}193 194static void mtk_dma_clr(struct mtk_cqdma_pchan *pc, u32 reg, u32 val)195{196	mtk_dma_rmw(pc, reg, val, 0);197}198 199static void mtk_cqdma_vdesc_free(struct virt_dma_desc *vd)200{201	kfree(to_cqdma_vdesc(vd));202}203 204static int mtk_cqdma_poll_engine_done(struct mtk_cqdma_pchan *pc, bool atomic)205{206	u32 status = 0;207 208	if (!atomic)209		return readl_poll_timeout(pc->base + MTK_CQDMA_EN,210					  status,211					  !(status & MTK_CQDMA_EN_BIT),212					  MTK_CQDMA_USEC_POLL,213					  MTK_CQDMA_TIMEOUT_POLL);214 215	return readl_poll_timeout_atomic(pc->base + MTK_CQDMA_EN,216					 status,217					 !(status & MTK_CQDMA_EN_BIT),218					 MTK_CQDMA_USEC_POLL,219					 MTK_CQDMA_TIMEOUT_POLL);220}221 222static int mtk_cqdma_hard_reset(struct mtk_cqdma_pchan *pc)223{224	mtk_dma_set(pc, MTK_CQDMA_RESET, MTK_CQDMA_HARD_RST_BIT);225	mtk_dma_clr(pc, MTK_CQDMA_RESET, MTK_CQDMA_HARD_RST_BIT);226 227	return mtk_cqdma_poll_engine_done(pc, true);228}229 230static void mtk_cqdma_start(struct mtk_cqdma_pchan *pc,231			    struct mtk_cqdma_vdesc *cvd)232{233	/* wait for the previous transaction done */234	if (mtk_cqdma_poll_engine_done(pc, true) < 0)235		dev_err(cqdma2dev(to_cqdma_dev(cvd->ch)), "cqdma wait transaction timeout\n");236 237	/* warm reset the dma engine for the new transaction */238	mtk_dma_set(pc, MTK_CQDMA_RESET, MTK_CQDMA_WARM_RST_BIT);239	if (mtk_cqdma_poll_engine_done(pc, true) < 0)240		dev_err(cqdma2dev(to_cqdma_dev(cvd->ch)), "cqdma warm reset timeout\n");241 242	/* setup the source */243	mtk_dma_set(pc, MTK_CQDMA_SRC, cvd->src & MTK_CQDMA_ADDR_LIMIT);244#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT245	mtk_dma_set(pc, MTK_CQDMA_SRC2, cvd->src >> MTK_CQDMA_ADDR2_SHFIT);246#else247	mtk_dma_set(pc, MTK_CQDMA_SRC2, 0);248#endif249 250	/* setup the destination */251	mtk_dma_set(pc, MTK_CQDMA_DST, cvd->dest & MTK_CQDMA_ADDR_LIMIT);252#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT253	mtk_dma_set(pc, MTK_CQDMA_DST2, cvd->dest >> MTK_CQDMA_ADDR2_SHFIT);254#else255	mtk_dma_set(pc, MTK_CQDMA_DST2, 0);256#endif257 258	/* setup the length */259	mtk_dma_set(pc, MTK_CQDMA_LEN1, cvd->len);260 261	/* start dma engine */262	mtk_dma_set(pc, MTK_CQDMA_EN, MTK_CQDMA_EN_BIT);263}264 265static void mtk_cqdma_issue_vchan_pending(struct mtk_cqdma_vchan *cvc)266{267	struct virt_dma_desc *vd, *vd2;268	struct mtk_cqdma_pchan *pc = cvc->pc;269	struct mtk_cqdma_vdesc *cvd;270	bool trigger_engine = false;271 272	lockdep_assert_held(&cvc->vc.lock);273	lockdep_assert_held(&pc->lock);274 275	list_for_each_entry_safe(vd, vd2, &cvc->vc.desc_issued, node) {276		/* need to trigger dma engine if PC's queue is empty */277		if (list_empty(&pc->queue))278			trigger_engine = true;279 280		cvd = to_cqdma_vdesc(vd);281 282		/* add VD into PC's queue */283		list_add_tail(&cvd->node, &pc->queue);284 285		/* start the dma engine */286		if (trigger_engine)287			mtk_cqdma_start(pc, cvd);288 289		/* remove VD from list desc_issued */290		list_del(&vd->node);291	}292}293 294/*295 * return true if this VC is active,296 * meaning that there are VDs under processing by the PC297 */298static bool mtk_cqdma_is_vchan_active(struct mtk_cqdma_vchan *cvc)299{300	struct mtk_cqdma_vdesc *cvd;301 302	list_for_each_entry(cvd, &cvc->pc->queue, node)303		if (cvc == to_cqdma_vchan(cvd->ch))304			return true;305 306	return false;307}308 309/*310 * return the pointer of the CVD that is just consumed by the PC311 */312static struct mtk_cqdma_vdesc313*mtk_cqdma_consume_work_queue(struct mtk_cqdma_pchan *pc)314{315	struct mtk_cqdma_vchan *cvc;316	struct mtk_cqdma_vdesc *cvd, *ret = NULL;317 318	/* consume a CVD from PC's queue */319	cvd = list_first_entry_or_null(&pc->queue,320				       struct mtk_cqdma_vdesc, node);321	if (unlikely(!cvd || !cvd->parent))322		return NULL;323 324	cvc = to_cqdma_vchan(cvd->ch);325	ret = cvd;326 327	/* update residue of the parent CVD */328	cvd->parent->residue -= cvd->len;329 330	/* delete CVD from PC's queue */331	list_del(&cvd->node);332 333	spin_lock(&cvc->vc.lock);334 335	/* check whether all the child CVDs completed */336	if (!cvd->parent->residue) {337		/* add the parent VD into list desc_completed */338		vchan_cookie_complete(&cvd->parent->vd);339 340		/* setup completion if this VC is under synchronization */341		if (cvc->issue_synchronize && !mtk_cqdma_is_vchan_active(cvc)) {342			complete(&cvc->issue_completion);343			cvc->issue_synchronize = false;344		}345	}346 347	spin_unlock(&cvc->vc.lock);348 349	/* start transaction for next CVD in the queue */350	cvd = list_first_entry_or_null(&pc->queue,351				       struct mtk_cqdma_vdesc, node);352	if (cvd)353		mtk_cqdma_start(pc, cvd);354 355	return ret;356}357 358static void mtk_cqdma_tasklet_cb(struct tasklet_struct *t)359{360	struct mtk_cqdma_pchan *pc = from_tasklet(pc, t, tasklet);361	struct mtk_cqdma_vdesc *cvd = NULL;362	unsigned long flags;363 364	spin_lock_irqsave(&pc->lock, flags);365	/* consume the queue */366	cvd = mtk_cqdma_consume_work_queue(pc);367	spin_unlock_irqrestore(&pc->lock, flags);368 369	/* submit the next CVD */370	if (cvd) {371		dma_run_dependencies(&cvd->vd.tx);372 373		/*374		 * free child CVD after completion.375		 * the parent CVD would be freed with desc_free by user.376		 */377		if (cvd->parent != cvd)378			kfree(cvd);379	}380 381	/* re-enable interrupt before leaving tasklet */382	enable_irq(pc->irq);383}384 385static irqreturn_t mtk_cqdma_irq(int irq, void *devid)386{387	struct mtk_cqdma_device *cqdma = devid;388	irqreturn_t ret = IRQ_NONE;389	bool schedule_tasklet = false;390	u32 i;391 392	/* clear interrupt flags for each PC */393	for (i = 0; i < cqdma->dma_channels; ++i, schedule_tasklet = false) {394		spin_lock(&cqdma->pc[i]->lock);395		if (mtk_dma_read(cqdma->pc[i],396				 MTK_CQDMA_INT_FLAG) & MTK_CQDMA_INT_FLAG_BIT) {397			/* clear interrupt */398			mtk_dma_clr(cqdma->pc[i], MTK_CQDMA_INT_FLAG,399				    MTK_CQDMA_INT_FLAG_BIT);400 401			schedule_tasklet = true;402			ret = IRQ_HANDLED;403		}404		spin_unlock(&cqdma->pc[i]->lock);405 406		if (schedule_tasklet) {407			/* disable interrupt */408			disable_irq_nosync(cqdma->pc[i]->irq);409 410			/* schedule the tasklet to handle the transactions */411			tasklet_schedule(&cqdma->pc[i]->tasklet);412		}413	}414 415	return ret;416}417 418static struct virt_dma_desc *mtk_cqdma_find_active_desc(struct dma_chan *c,419							dma_cookie_t cookie)420{421	struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c);422	struct virt_dma_desc *vd;423	unsigned long flags;424 425	spin_lock_irqsave(&cvc->pc->lock, flags);426	list_for_each_entry(vd, &cvc->pc->queue, node)427		if (vd->tx.cookie == cookie) {428			spin_unlock_irqrestore(&cvc->pc->lock, flags);429			return vd;430		}431	spin_unlock_irqrestore(&cvc->pc->lock, flags);432 433	list_for_each_entry(vd, &cvc->vc.desc_issued, node)434		if (vd->tx.cookie == cookie)435			return vd;436 437	return NULL;438}439 440static enum dma_status mtk_cqdma_tx_status(struct dma_chan *c,441					   dma_cookie_t cookie,442					   struct dma_tx_state *txstate)443{444	struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c);445	struct mtk_cqdma_vdesc *cvd;446	struct virt_dma_desc *vd;447	enum dma_status ret;448	unsigned long flags;449	size_t bytes = 0;450 451	ret = dma_cookie_status(c, cookie, txstate);452	if (ret == DMA_COMPLETE || !txstate)453		return ret;454 455	spin_lock_irqsave(&cvc->vc.lock, flags);456	vd = mtk_cqdma_find_active_desc(c, cookie);457	spin_unlock_irqrestore(&cvc->vc.lock, flags);458 459	if (vd) {460		cvd = to_cqdma_vdesc(vd);461		bytes = cvd->residue;462	}463 464	dma_set_residue(txstate, bytes);465 466	return ret;467}468 469static void mtk_cqdma_issue_pending(struct dma_chan *c)470{471	struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c);472	unsigned long pc_flags;473	unsigned long vc_flags;474 475	/* acquire PC's lock before VS's lock for lock dependency in tasklet */476	spin_lock_irqsave(&cvc->pc->lock, pc_flags);477	spin_lock_irqsave(&cvc->vc.lock, vc_flags);478 479	if (vchan_issue_pending(&cvc->vc))480		mtk_cqdma_issue_vchan_pending(cvc);481 482	spin_unlock_irqrestore(&cvc->vc.lock, vc_flags);483	spin_unlock_irqrestore(&cvc->pc->lock, pc_flags);484}485 486static struct dma_async_tx_descriptor *487mtk_cqdma_prep_dma_memcpy(struct dma_chan *c, dma_addr_t dest,488			  dma_addr_t src, size_t len, unsigned long flags)489{490	struct mtk_cqdma_vdesc **cvd;491	struct dma_async_tx_descriptor *tx = NULL, *prev_tx = NULL;492	size_t i, tlen, nr_vd;493 494	/*495	 * In the case that trsanction length is larger than the496	 * DMA engine supports, a single memcpy transaction needs497	 * to be separated into several DMA transactions.498	 * Each DMA transaction would be described by a CVD,499	 * and the first one is referred as the parent CVD,500	 * while the others are child CVDs.501	 * The parent CVD's tx descriptor is the only tx descriptor502	 * returned to the DMA user, and it should not be completed503	 * until all the child CVDs completed.504	 */505	nr_vd = DIV_ROUND_UP(len, MTK_CQDMA_MAX_LEN);506	cvd = kcalloc(nr_vd, sizeof(*cvd), GFP_NOWAIT);507	if (!cvd)508		return NULL;509 510	for (i = 0; i < nr_vd; ++i) {511		cvd[i] = kzalloc(sizeof(*cvd[i]), GFP_NOWAIT);512		if (!cvd[i]) {513			for (; i > 0; --i)514				kfree(cvd[i - 1]);515			return NULL;516		}517 518		/* setup dma channel */519		cvd[i]->ch = c;520 521		/* setup source, destination, and length */522		tlen = (len > MTK_CQDMA_MAX_LEN) ? MTK_CQDMA_MAX_LEN : len;523		cvd[i]->len = tlen;524		cvd[i]->src = src;525		cvd[i]->dest = dest;526 527		/* setup tx descriptor */528		tx = vchan_tx_prep(to_virt_chan(c), &cvd[i]->vd, flags);529		tx->next = NULL;530 531		if (!i) {532			cvd[0]->residue = len;533		} else {534			prev_tx->next = tx;535			cvd[i]->residue = tlen;536		}537 538		cvd[i]->parent = cvd[0];539 540		/* update the src, dest, len, prev_tx for the next CVD */541		src += tlen;542		dest += tlen;543		len -= tlen;544		prev_tx = tx;545	}546 547	return &cvd[0]->vd.tx;548}549 550static void mtk_cqdma_free_inactive_desc(struct dma_chan *c)551{552	struct virt_dma_chan *vc = to_virt_chan(c);553	unsigned long flags;554	LIST_HEAD(head);555 556	/*557	 * set desc_allocated, desc_submitted,558	 * and desc_issued as the candicates to be freed559	 */560	spin_lock_irqsave(&vc->lock, flags);561	list_splice_tail_init(&vc->desc_allocated, &head);562	list_splice_tail_init(&vc->desc_submitted, &head);563	list_splice_tail_init(&vc->desc_issued, &head);564	spin_unlock_irqrestore(&vc->lock, flags);565 566	/* free descriptor lists */567	vchan_dma_desc_free_list(vc, &head);568}569 570static void mtk_cqdma_free_active_desc(struct dma_chan *c)571{572	struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c);573	bool sync_needed = false;574	unsigned long pc_flags;575	unsigned long vc_flags;576 577	/* acquire PC's lock first due to lock dependency in dma ISR */578	spin_lock_irqsave(&cvc->pc->lock, pc_flags);579	spin_lock_irqsave(&cvc->vc.lock, vc_flags);580 581	/* synchronization is required if this VC is active */582	if (mtk_cqdma_is_vchan_active(cvc)) {583		cvc->issue_synchronize = true;584		sync_needed = true;585	}586 587	spin_unlock_irqrestore(&cvc->vc.lock, vc_flags);588	spin_unlock_irqrestore(&cvc->pc->lock, pc_flags);589 590	/* waiting for the completion of this VC */591	if (sync_needed)592		wait_for_completion(&cvc->issue_completion);593 594	/* free all descriptors in list desc_completed */595	vchan_synchronize(&cvc->vc);596 597	WARN_ONCE(!list_empty(&cvc->vc.desc_completed),598		  "Desc pending still in list desc_completed\n");599}600 601static int mtk_cqdma_terminate_all(struct dma_chan *c)602{603	/* free descriptors not processed yet by hardware */604	mtk_cqdma_free_inactive_desc(c);605 606	/* free descriptors being processed by hardware */607	mtk_cqdma_free_active_desc(c);608 609	return 0;610}611 612static int mtk_cqdma_alloc_chan_resources(struct dma_chan *c)613{614	struct mtk_cqdma_device *cqdma = to_cqdma_dev(c);615	struct mtk_cqdma_vchan *vc = to_cqdma_vchan(c);616	struct mtk_cqdma_pchan *pc = NULL;617	u32 i, min_refcnt = U32_MAX, refcnt;618	unsigned long flags;619 620	/* allocate PC with the minimum refcount */621	for (i = 0; i < cqdma->dma_channels; ++i) {622		refcnt = refcount_read(&cqdma->pc[i]->refcnt);623		if (refcnt < min_refcnt) {624			pc = cqdma->pc[i];625			min_refcnt = refcnt;626		}627	}628 629	if (!pc)630		return -ENOSPC;631 632	spin_lock_irqsave(&pc->lock, flags);633 634	if (!refcount_read(&pc->refcnt)) {635		/* allocate PC when the refcount is zero */636		mtk_cqdma_hard_reset(pc);637 638		/* enable interrupt for this PC */639		mtk_dma_set(pc, MTK_CQDMA_INT_EN, MTK_CQDMA_INT_EN_BIT);640 641		/*642		 * refcount_inc would complain increment on 0; use-after-free.643		 * Thus, we need to explicitly set it as 1 initially.644		 */645		refcount_set(&pc->refcnt, 1);646	} else {647		refcount_inc(&pc->refcnt);648	}649 650	spin_unlock_irqrestore(&pc->lock, flags);651 652	vc->pc = pc;653 654	return 0;655}656 657static void mtk_cqdma_free_chan_resources(struct dma_chan *c)658{659	struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c);660	unsigned long flags;661 662	/* free all descriptors in all lists on the VC */663	mtk_cqdma_terminate_all(c);664 665	spin_lock_irqsave(&cvc->pc->lock, flags);666 667	/* PC is not freed until there is no VC mapped to it */668	if (refcount_dec_and_test(&cvc->pc->refcnt)) {669		/* start the flush operation and stop the engine */670		mtk_dma_set(cvc->pc, MTK_CQDMA_FLUSH, MTK_CQDMA_FLUSH_BIT);671 672		/* wait for the completion of flush operation */673		if (mtk_cqdma_poll_engine_done(cvc->pc, true) < 0)674			dev_err(cqdma2dev(to_cqdma_dev(c)), "cqdma flush timeout\n");675 676		/* clear the flush bit and interrupt flag */677		mtk_dma_clr(cvc->pc, MTK_CQDMA_FLUSH, MTK_CQDMA_FLUSH_BIT);678		mtk_dma_clr(cvc->pc, MTK_CQDMA_INT_FLAG,679			    MTK_CQDMA_INT_FLAG_BIT);680 681		/* disable interrupt for this PC */682		mtk_dma_clr(cvc->pc, MTK_CQDMA_INT_EN, MTK_CQDMA_INT_EN_BIT);683	}684 685	spin_unlock_irqrestore(&cvc->pc->lock, flags);686}687 688static int mtk_cqdma_hw_init(struct mtk_cqdma_device *cqdma)689{690	unsigned long flags;691	int err;692	u32 i;693 694	pm_runtime_enable(cqdma2dev(cqdma));695	pm_runtime_get_sync(cqdma2dev(cqdma));696 697	err = clk_prepare_enable(cqdma->clk);698 699	if (err) {700		pm_runtime_put_sync(cqdma2dev(cqdma));701		pm_runtime_disable(cqdma2dev(cqdma));702		return err;703	}704 705	/* reset all PCs */706	for (i = 0; i < cqdma->dma_channels; ++i) {707		spin_lock_irqsave(&cqdma->pc[i]->lock, flags);708		if (mtk_cqdma_hard_reset(cqdma->pc[i]) < 0) {709			dev_err(cqdma2dev(cqdma), "cqdma hard reset timeout\n");710			spin_unlock_irqrestore(&cqdma->pc[i]->lock, flags);711 712			clk_disable_unprepare(cqdma->clk);713			pm_runtime_put_sync(cqdma2dev(cqdma));714			pm_runtime_disable(cqdma2dev(cqdma));715			return -EINVAL;716		}717		spin_unlock_irqrestore(&cqdma->pc[i]->lock, flags);718	}719 720	return 0;721}722 723static void mtk_cqdma_hw_deinit(struct mtk_cqdma_device *cqdma)724{725	unsigned long flags;726	u32 i;727 728	/* reset all PCs */729	for (i = 0; i < cqdma->dma_channels; ++i) {730		spin_lock_irqsave(&cqdma->pc[i]->lock, flags);731		if (mtk_cqdma_hard_reset(cqdma->pc[i]) < 0)732			dev_err(cqdma2dev(cqdma), "cqdma hard reset timeout\n");733		spin_unlock_irqrestore(&cqdma->pc[i]->lock, flags);734	}735 736	clk_disable_unprepare(cqdma->clk);737 738	pm_runtime_put_sync(cqdma2dev(cqdma));739	pm_runtime_disable(cqdma2dev(cqdma));740}741 742static const struct of_device_id mtk_cqdma_match[] = {743	{ .compatible = "mediatek,mt6765-cqdma" },744	{ /* sentinel */ }745};746MODULE_DEVICE_TABLE(of, mtk_cqdma_match);747 748static int mtk_cqdma_probe(struct platform_device *pdev)749{750	struct mtk_cqdma_device *cqdma;751	struct mtk_cqdma_vchan *vc;752	struct dma_device *dd;753	int err;754	u32 i;755 756	cqdma = devm_kzalloc(&pdev->dev, sizeof(*cqdma), GFP_KERNEL);757	if (!cqdma)758		return -ENOMEM;759 760	dd = &cqdma->ddev;761 762	cqdma->clk = devm_clk_get(&pdev->dev, "cqdma");763	if (IS_ERR(cqdma->clk)) {764		dev_err(&pdev->dev, "No clock for %s\n",765			dev_name(&pdev->dev));766		return PTR_ERR(cqdma->clk);767	}768 769	dma_cap_set(DMA_MEMCPY, dd->cap_mask);770 771	dd->copy_align = MTK_CQDMA_ALIGN_SIZE;772	dd->device_alloc_chan_resources = mtk_cqdma_alloc_chan_resources;773	dd->device_free_chan_resources = mtk_cqdma_free_chan_resources;774	dd->device_tx_status = mtk_cqdma_tx_status;775	dd->device_issue_pending = mtk_cqdma_issue_pending;776	dd->device_prep_dma_memcpy = mtk_cqdma_prep_dma_memcpy;777	dd->device_terminate_all = mtk_cqdma_terminate_all;778	dd->src_addr_widths = MTK_CQDMA_DMA_BUSWIDTHS;779	dd->dst_addr_widths = MTK_CQDMA_DMA_BUSWIDTHS;780	dd->directions = BIT(DMA_MEM_TO_MEM);781	dd->residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;782	dd->dev = &pdev->dev;783	INIT_LIST_HEAD(&dd->channels);784 785	if (pdev->dev.of_node && of_property_read_u32(pdev->dev.of_node,786						      "dma-requests",787						      &cqdma->dma_requests)) {788		dev_info(&pdev->dev,789			 "Using %u as missing dma-requests property\n",790			 MTK_CQDMA_NR_VCHANS);791 792		cqdma->dma_requests = MTK_CQDMA_NR_VCHANS;793	}794 795	if (pdev->dev.of_node && of_property_read_u32(pdev->dev.of_node,796						      "dma-channels",797						      &cqdma->dma_channels)) {798		dev_info(&pdev->dev,799			 "Using %u as missing dma-channels property\n",800			 MTK_CQDMA_NR_PCHANS);801 802		cqdma->dma_channels = MTK_CQDMA_NR_PCHANS;803	}804 805	cqdma->pc = devm_kcalloc(&pdev->dev, cqdma->dma_channels,806				 sizeof(*cqdma->pc), GFP_KERNEL);807	if (!cqdma->pc)808		return -ENOMEM;809 810	/* initialization for PCs */811	for (i = 0; i < cqdma->dma_channels; ++i) {812		cqdma->pc[i] = devm_kcalloc(&pdev->dev, 1,813					    sizeof(**cqdma->pc), GFP_KERNEL);814		if (!cqdma->pc[i])815			return -ENOMEM;816 817		INIT_LIST_HEAD(&cqdma->pc[i]->queue);818		spin_lock_init(&cqdma->pc[i]->lock);819		refcount_set(&cqdma->pc[i]->refcnt, 0);820		cqdma->pc[i]->base = devm_platform_ioremap_resource(pdev, i);821		if (IS_ERR(cqdma->pc[i]->base))822			return PTR_ERR(cqdma->pc[i]->base);823 824		/* allocate IRQ resource */825		err = platform_get_irq(pdev, i);826		if (err < 0)827			return err;828		cqdma->pc[i]->irq = err;829 830		err = devm_request_irq(&pdev->dev, cqdma->pc[i]->irq,831				       mtk_cqdma_irq, 0, dev_name(&pdev->dev),832				       cqdma);833		if (err) {834			dev_err(&pdev->dev,835				"request_irq failed with err %d\n", err);836			return -EINVAL;837		}838	}839 840	/* allocate resource for VCs */841	cqdma->vc = devm_kcalloc(&pdev->dev, cqdma->dma_requests,842				 sizeof(*cqdma->vc), GFP_KERNEL);843	if (!cqdma->vc)844		return -ENOMEM;845 846	for (i = 0; i < cqdma->dma_requests; i++) {847		vc = &cqdma->vc[i];848		vc->vc.desc_free = mtk_cqdma_vdesc_free;849		vchan_init(&vc->vc, dd);850		init_completion(&vc->issue_completion);851	}852 853	err = dma_async_device_register(dd);854	if (err)855		return err;856 857	err = of_dma_controller_register(pdev->dev.of_node,858					 of_dma_xlate_by_chan_id, cqdma);859	if (err) {860		dev_err(&pdev->dev,861			"MediaTek CQDMA OF registration failed %d\n", err);862		goto err_unregister;863	}864 865	err = mtk_cqdma_hw_init(cqdma);866	if (err) {867		dev_err(&pdev->dev,868			"MediaTek CQDMA HW initialization failed %d\n", err);869		goto err_unregister;870	}871 872	platform_set_drvdata(pdev, cqdma);873 874	/* initialize tasklet for each PC */875	for (i = 0; i < cqdma->dma_channels; ++i)876		tasklet_setup(&cqdma->pc[i]->tasklet, mtk_cqdma_tasklet_cb);877 878	dev_info(&pdev->dev, "MediaTek CQDMA driver registered\n");879 880	return 0;881 882err_unregister:883	dma_async_device_unregister(dd);884 885	return err;886}887 888static void mtk_cqdma_remove(struct platform_device *pdev)889{890	struct mtk_cqdma_device *cqdma = platform_get_drvdata(pdev);891	struct mtk_cqdma_vchan *vc;892	unsigned long flags;893	int i;894 895	/* kill VC task */896	for (i = 0; i < cqdma->dma_requests; i++) {897		vc = &cqdma->vc[i];898 899		list_del(&vc->vc.chan.device_node);900		tasklet_kill(&vc->vc.task);901	}902 903	/* disable interrupt */904	for (i = 0; i < cqdma->dma_channels; i++) {905		spin_lock_irqsave(&cqdma->pc[i]->lock, flags);906		mtk_dma_clr(cqdma->pc[i], MTK_CQDMA_INT_EN,907			    MTK_CQDMA_INT_EN_BIT);908		spin_unlock_irqrestore(&cqdma->pc[i]->lock, flags);909 910		/* Waits for any pending IRQ handlers to complete */911		synchronize_irq(cqdma->pc[i]->irq);912 913		tasklet_kill(&cqdma->pc[i]->tasklet);914	}915 916	/* disable hardware */917	mtk_cqdma_hw_deinit(cqdma);918 919	dma_async_device_unregister(&cqdma->ddev);920	of_dma_controller_free(pdev->dev.of_node);921}922 923static struct platform_driver mtk_cqdma_driver = {924	.probe = mtk_cqdma_probe,925	.remove_new = mtk_cqdma_remove,926	.driver = {927		.name           = KBUILD_MODNAME,928		.of_match_table = mtk_cqdma_match,929	},930};931module_platform_driver(mtk_cqdma_driver);932 933MODULE_DESCRIPTION("MediaTek CQDMA Controller Driver");934MODULE_AUTHOR("Shun-Chih Yu <shun-chih.yu@mediatek.com>");935MODULE_LICENSE("GPL v2");936