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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Topcliff PCH DMA controller driver4 * Copyright (c) 2010 Intel Corporation5 * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.6 */7 8#include <linux/dmaengine.h>9#include <linux/dma-mapping.h>10#include <linux/init.h>11#include <linux/pci.h>12#include <linux/slab.h>13#include <linux/interrupt.h>14#include <linux/module.h>15#include <linux/pch_dma.h>16 17#include "dmaengine.h"18 19#define DRV_NAME "pch-dma"20 21#define DMA_CTL0_DISABLE		0x022#define DMA_CTL0_SG			0x123#define DMA_CTL0_ONESHOT		0x224#define DMA_CTL0_MODE_MASK_BITS		0x325#define DMA_CTL0_DIR_SHIFT_BITS		226#define DMA_CTL0_BITS_PER_CH		427 28#define DMA_CTL2_START_SHIFT_BITS	829#define DMA_CTL2_IRQ_ENABLE_MASK	((1UL << DMA_CTL2_START_SHIFT_BITS) - 1)30 31#define DMA_STATUS_IDLE			0x032#define DMA_STATUS_DESC_READ		0x133#define DMA_STATUS_WAIT			0x234#define DMA_STATUS_ACCESS		0x335#define DMA_STATUS_BITS_PER_CH		236#define DMA_STATUS_MASK_BITS		0x337#define DMA_STATUS_SHIFT_BITS		1638#define DMA_STATUS_IRQ(x)		(0x1 << (x))39#define DMA_STATUS0_ERR(x)		(0x1 << ((x) + 8))40#define DMA_STATUS2_ERR(x)		(0x1 << (x))41 42#define DMA_DESC_WIDTH_SHIFT_BITS	1243#define DMA_DESC_WIDTH_1_BYTE		(0x3 << DMA_DESC_WIDTH_SHIFT_BITS)44#define DMA_DESC_WIDTH_2_BYTES		(0x2 << DMA_DESC_WIDTH_SHIFT_BITS)45#define DMA_DESC_WIDTH_4_BYTES		(0x0 << DMA_DESC_WIDTH_SHIFT_BITS)46#define DMA_DESC_MAX_COUNT_1_BYTE	0x3FF47#define DMA_DESC_MAX_COUNT_2_BYTES	0x3FF48#define DMA_DESC_MAX_COUNT_4_BYTES	0x7FF49#define DMA_DESC_END_WITHOUT_IRQ	0x050#define DMA_DESC_END_WITH_IRQ		0x151#define DMA_DESC_FOLLOW_WITHOUT_IRQ	0x252#define DMA_DESC_FOLLOW_WITH_IRQ	0x353 54#define MAX_CHAN_NR			1255 56#define DMA_MASK_CTL0_MODE	0x3333333357#define DMA_MASK_CTL2_MODE	0x0000333358 59static unsigned int init_nr_desc_per_channel = 64;60module_param(init_nr_desc_per_channel, uint, 0644);61MODULE_PARM_DESC(init_nr_desc_per_channel,62		 "initial descriptors per channel (default: 64)");63 64struct pch_dma_desc_regs {65	u32	dev_addr;66	u32	mem_addr;67	u32	size;68	u32	next;69};70 71struct pch_dma_regs {72	u32	dma_ctl0;73	u32	dma_ctl1;74	u32	dma_ctl2;75	u32	dma_ctl3;76	u32	dma_sts0;77	u32	dma_sts1;78	u32	dma_sts2;79	u32	reserved3;80	struct pch_dma_desc_regs desc[MAX_CHAN_NR];81};82 83struct pch_dma_desc {84	struct pch_dma_desc_regs regs;85	struct dma_async_tx_descriptor txd;86	struct list_head	desc_node;87	struct list_head	tx_list;88};89 90struct pch_dma_chan {91	struct dma_chan		chan;92	void __iomem *membase;93	enum dma_transfer_direction dir;94	struct tasklet_struct	tasklet;95	unsigned long		err_status;96 97	spinlock_t		lock;98 99	struct list_head	active_list;100	struct list_head	queue;101	struct list_head	free_list;102	unsigned int		descs_allocated;103};104 105#define PDC_DEV_ADDR	0x00106#define PDC_MEM_ADDR	0x04107#define PDC_SIZE	0x08108#define PDC_NEXT	0x0C109 110#define channel_readl(pdc, name) \111	readl((pdc)->membase + PDC_##name)112#define channel_writel(pdc, name, val) \113	writel((val), (pdc)->membase + PDC_##name)114 115struct pch_dma {116	struct dma_device	dma;117	void __iomem *membase;118	struct dma_pool		*pool;119	struct pch_dma_regs	regs;120	struct pch_dma_desc_regs ch_regs[MAX_CHAN_NR];121	struct pch_dma_chan	channels[MAX_CHAN_NR];122};123 124#define PCH_DMA_CTL0	0x00125#define PCH_DMA_CTL1	0x04126#define PCH_DMA_CTL2	0x08127#define PCH_DMA_CTL3	0x0C128#define PCH_DMA_STS0	0x10129#define PCH_DMA_STS1	0x14130#define PCH_DMA_STS2	0x18131 132#define dma_readl(pd, name) \133	readl((pd)->membase + PCH_DMA_##name)134#define dma_writel(pd, name, val) \135	writel((val), (pd)->membase + PCH_DMA_##name)136 137static inline138struct pch_dma_desc *to_pd_desc(struct dma_async_tx_descriptor *txd)139{140	return container_of(txd, struct pch_dma_desc, txd);141}142 143static inline struct pch_dma_chan *to_pd_chan(struct dma_chan *chan)144{145	return container_of(chan, struct pch_dma_chan, chan);146}147 148static inline struct pch_dma *to_pd(struct dma_device *ddev)149{150	return container_of(ddev, struct pch_dma, dma);151}152 153static inline struct device *chan2dev(struct dma_chan *chan)154{155	return &chan->dev->device;156}157 158static inline159struct pch_dma_desc *pdc_first_active(struct pch_dma_chan *pd_chan)160{161	return list_first_entry(&pd_chan->active_list,162				struct pch_dma_desc, desc_node);163}164 165static inline166struct pch_dma_desc *pdc_first_queued(struct pch_dma_chan *pd_chan)167{168	return list_first_entry(&pd_chan->queue,169				struct pch_dma_desc, desc_node);170}171 172static void pdc_enable_irq(struct dma_chan *chan, int enable)173{174	struct pch_dma *pd = to_pd(chan->device);175	u32 val;176	int pos;177 178	if (chan->chan_id < 8)179		pos = chan->chan_id;180	else181		pos = chan->chan_id + 8;182 183	val = dma_readl(pd, CTL2);184 185	if (enable)186		val |= 0x1 << pos;187	else188		val &= ~(0x1 << pos);189 190	dma_writel(pd, CTL2, val);191 192	dev_dbg(chan2dev(chan), "pdc_enable_irq: chan %d -> %x\n",193		chan->chan_id, val);194}195 196static void pdc_set_dir(struct dma_chan *chan)197{198	struct pch_dma_chan *pd_chan = to_pd_chan(chan);199	struct pch_dma *pd = to_pd(chan->device);200	u32 val;201	u32 mask_mode;202	u32 mask_ctl;203 204	if (chan->chan_id < 8) {205		val = dma_readl(pd, CTL0);206 207		mask_mode = DMA_CTL0_MODE_MASK_BITS <<208					(DMA_CTL0_BITS_PER_CH * chan->chan_id);209		mask_ctl = DMA_MASK_CTL0_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<210				       (DMA_CTL0_BITS_PER_CH * chan->chan_id));211		val &= mask_mode;212		if (pd_chan->dir == DMA_MEM_TO_DEV)213			val |= 0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +214				       DMA_CTL0_DIR_SHIFT_BITS);215		else216			val &= ~(0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +217					 DMA_CTL0_DIR_SHIFT_BITS));218 219		val |= mask_ctl;220		dma_writel(pd, CTL0, val);221	} else {222		int ch = chan->chan_id - 8; /* ch8-->0 ch9-->1 ... ch11->3 */223		val = dma_readl(pd, CTL3);224 225		mask_mode = DMA_CTL0_MODE_MASK_BITS <<226						(DMA_CTL0_BITS_PER_CH * ch);227		mask_ctl = DMA_MASK_CTL2_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<228						 (DMA_CTL0_BITS_PER_CH * ch));229		val &= mask_mode;230		if (pd_chan->dir == DMA_MEM_TO_DEV)231			val |= 0x1 << (DMA_CTL0_BITS_PER_CH * ch +232				       DMA_CTL0_DIR_SHIFT_BITS);233		else234			val &= ~(0x1 << (DMA_CTL0_BITS_PER_CH * ch +235					 DMA_CTL0_DIR_SHIFT_BITS));236		val |= mask_ctl;237		dma_writel(pd, CTL3, val);238	}239 240	dev_dbg(chan2dev(chan), "pdc_set_dir: chan %d -> %x\n",241		chan->chan_id, val);242}243 244static void pdc_set_mode(struct dma_chan *chan, u32 mode)245{246	struct pch_dma *pd = to_pd(chan->device);247	u32 val;248	u32 mask_ctl;249	u32 mask_dir;250 251	if (chan->chan_id < 8) {252		mask_ctl = DMA_MASK_CTL0_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<253			   (DMA_CTL0_BITS_PER_CH * chan->chan_id));254		mask_dir = 1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +\255				 DMA_CTL0_DIR_SHIFT_BITS);256		val = dma_readl(pd, CTL0);257		val &= mask_dir;258		val |= mode << (DMA_CTL0_BITS_PER_CH * chan->chan_id);259		val |= mask_ctl;260		dma_writel(pd, CTL0, val);261	} else {262		int ch = chan->chan_id - 8; /* ch8-->0 ch9-->1 ... ch11->3 */263		mask_ctl = DMA_MASK_CTL2_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<264						 (DMA_CTL0_BITS_PER_CH * ch));265		mask_dir = 1 << (DMA_CTL0_BITS_PER_CH * ch +\266				 DMA_CTL0_DIR_SHIFT_BITS);267		val = dma_readl(pd, CTL3);268		val &= mask_dir;269		val |= mode << (DMA_CTL0_BITS_PER_CH * ch);270		val |= mask_ctl;271		dma_writel(pd, CTL3, val);272	}273 274	dev_dbg(chan2dev(chan), "pdc_set_mode: chan %d -> %x\n",275		chan->chan_id, val);276}277 278static u32 pdc_get_status0(struct pch_dma_chan *pd_chan)279{280	struct pch_dma *pd = to_pd(pd_chan->chan.device);281	u32 val;282 283	val = dma_readl(pd, STS0);284	return DMA_STATUS_MASK_BITS & (val >> (DMA_STATUS_SHIFT_BITS +285			DMA_STATUS_BITS_PER_CH * pd_chan->chan.chan_id));286}287 288static u32 pdc_get_status2(struct pch_dma_chan *pd_chan)289{290	struct pch_dma *pd = to_pd(pd_chan->chan.device);291	u32 val;292 293	val = dma_readl(pd, STS2);294	return DMA_STATUS_MASK_BITS & (val >> (DMA_STATUS_SHIFT_BITS +295			DMA_STATUS_BITS_PER_CH * (pd_chan->chan.chan_id - 8)));296}297 298static bool pdc_is_idle(struct pch_dma_chan *pd_chan)299{300	u32 sts;301 302	if (pd_chan->chan.chan_id < 8)303		sts = pdc_get_status0(pd_chan);304	else305		sts = pdc_get_status2(pd_chan);306 307 308	if (sts == DMA_STATUS_IDLE)309		return true;310	else311		return false;312}313 314static void pdc_dostart(struct pch_dma_chan *pd_chan, struct pch_dma_desc* desc)315{316	if (!pdc_is_idle(pd_chan)) {317		dev_err(chan2dev(&pd_chan->chan),318			"BUG: Attempt to start non-idle channel\n");319		return;320	}321 322	dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> dev_addr: %x\n",323		pd_chan->chan.chan_id, desc->regs.dev_addr);324	dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> mem_addr: %x\n",325		pd_chan->chan.chan_id, desc->regs.mem_addr);326	dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> size: %x\n",327		pd_chan->chan.chan_id, desc->regs.size);328	dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> next: %x\n",329		pd_chan->chan.chan_id, desc->regs.next);330 331	if (list_empty(&desc->tx_list)) {332		channel_writel(pd_chan, DEV_ADDR, desc->regs.dev_addr);333		channel_writel(pd_chan, MEM_ADDR, desc->regs.mem_addr);334		channel_writel(pd_chan, SIZE, desc->regs.size);335		channel_writel(pd_chan, NEXT, desc->regs.next);336		pdc_set_mode(&pd_chan->chan, DMA_CTL0_ONESHOT);337	} else {338		channel_writel(pd_chan, NEXT, desc->txd.phys);339		pdc_set_mode(&pd_chan->chan, DMA_CTL0_SG);340	}341}342 343static void pdc_chain_complete(struct pch_dma_chan *pd_chan,344			       struct pch_dma_desc *desc)345{346	struct dma_async_tx_descriptor *txd = &desc->txd;347	struct dmaengine_desc_callback cb;348 349	dmaengine_desc_get_callback(txd, &cb);350	list_splice_init(&desc->tx_list, &pd_chan->free_list);351	list_move(&desc->desc_node, &pd_chan->free_list);352 353	dmaengine_desc_callback_invoke(&cb, NULL);354}355 356static void pdc_complete_all(struct pch_dma_chan *pd_chan)357{358	struct pch_dma_desc *desc, *_d;359	LIST_HEAD(list);360 361	BUG_ON(!pdc_is_idle(pd_chan));362 363	if (!list_empty(&pd_chan->queue))364		pdc_dostart(pd_chan, pdc_first_queued(pd_chan));365 366	list_splice_init(&pd_chan->active_list, &list);367	list_splice_init(&pd_chan->queue, &pd_chan->active_list);368 369	list_for_each_entry_safe(desc, _d, &list, desc_node)370		pdc_chain_complete(pd_chan, desc);371}372 373static void pdc_handle_error(struct pch_dma_chan *pd_chan)374{375	struct pch_dma_desc *bad_desc;376 377	bad_desc = pdc_first_active(pd_chan);378	list_del(&bad_desc->desc_node);379 380	list_splice_init(&pd_chan->queue, pd_chan->active_list.prev);381 382	if (!list_empty(&pd_chan->active_list))383		pdc_dostart(pd_chan, pdc_first_active(pd_chan));384 385	dev_crit(chan2dev(&pd_chan->chan), "Bad descriptor submitted\n");386	dev_crit(chan2dev(&pd_chan->chan), "descriptor cookie: %d\n",387		 bad_desc->txd.cookie);388 389	pdc_chain_complete(pd_chan, bad_desc);390}391 392static void pdc_advance_work(struct pch_dma_chan *pd_chan)393{394	if (list_empty(&pd_chan->active_list) ||395		list_is_singular(&pd_chan->active_list)) {396		pdc_complete_all(pd_chan);397	} else {398		pdc_chain_complete(pd_chan, pdc_first_active(pd_chan));399		pdc_dostart(pd_chan, pdc_first_active(pd_chan));400	}401}402 403static dma_cookie_t pd_tx_submit(struct dma_async_tx_descriptor *txd)404{405	struct pch_dma_desc *desc = to_pd_desc(txd);406	struct pch_dma_chan *pd_chan = to_pd_chan(txd->chan);407 408	spin_lock(&pd_chan->lock);409 410	if (list_empty(&pd_chan->active_list)) {411		list_add_tail(&desc->desc_node, &pd_chan->active_list);412		pdc_dostart(pd_chan, desc);413	} else {414		list_add_tail(&desc->desc_node, &pd_chan->queue);415	}416 417	spin_unlock(&pd_chan->lock);418	return 0;419}420 421static struct pch_dma_desc *pdc_alloc_desc(struct dma_chan *chan, gfp_t flags)422{423	struct pch_dma_desc *desc = NULL;424	struct pch_dma *pd = to_pd(chan->device);425	dma_addr_t addr;426 427	desc = dma_pool_zalloc(pd->pool, flags, &addr);428	if (desc) {429		INIT_LIST_HEAD(&desc->tx_list);430		dma_async_tx_descriptor_init(&desc->txd, chan);431		desc->txd.tx_submit = pd_tx_submit;432		desc->txd.flags = DMA_CTRL_ACK;433		desc->txd.phys = addr;434	}435 436	return desc;437}438 439static struct pch_dma_desc *pdc_desc_get(struct pch_dma_chan *pd_chan)440{441	struct pch_dma_desc *desc, *_d;442	struct pch_dma_desc *ret = NULL;443	int i = 0;444 445	spin_lock(&pd_chan->lock);446	list_for_each_entry_safe(desc, _d, &pd_chan->free_list, desc_node) {447		i++;448		if (async_tx_test_ack(&desc->txd)) {449			list_del(&desc->desc_node);450			ret = desc;451			break;452		}453		dev_dbg(chan2dev(&pd_chan->chan), "desc %p not ACKed\n", desc);454	}455	spin_unlock(&pd_chan->lock);456	dev_dbg(chan2dev(&pd_chan->chan), "scanned %d descriptors\n", i);457 458	if (!ret) {459		ret = pdc_alloc_desc(&pd_chan->chan, GFP_ATOMIC);460		if (ret) {461			spin_lock(&pd_chan->lock);462			pd_chan->descs_allocated++;463			spin_unlock(&pd_chan->lock);464		} else {465			dev_err(chan2dev(&pd_chan->chan),466				"failed to alloc desc\n");467		}468	}469 470	return ret;471}472 473static void pdc_desc_put(struct pch_dma_chan *pd_chan,474			 struct pch_dma_desc *desc)475{476	if (desc) {477		spin_lock(&pd_chan->lock);478		list_splice_init(&desc->tx_list, &pd_chan->free_list);479		list_add(&desc->desc_node, &pd_chan->free_list);480		spin_unlock(&pd_chan->lock);481	}482}483 484static int pd_alloc_chan_resources(struct dma_chan *chan)485{486	struct pch_dma_chan *pd_chan = to_pd_chan(chan);487	struct pch_dma_desc *desc;488	LIST_HEAD(tmp_list);489	int i;490 491	if (!pdc_is_idle(pd_chan)) {492		dev_dbg(chan2dev(chan), "DMA channel not idle ?\n");493		return -EIO;494	}495 496	if (!list_empty(&pd_chan->free_list))497		return pd_chan->descs_allocated;498 499	for (i = 0; i < init_nr_desc_per_channel; i++) {500		desc = pdc_alloc_desc(chan, GFP_KERNEL);501 502		if (!desc) {503			dev_warn(chan2dev(chan),504				"Only allocated %d initial descriptors\n", i);505			break;506		}507 508		list_add_tail(&desc->desc_node, &tmp_list);509	}510 511	spin_lock_irq(&pd_chan->lock);512	list_splice(&tmp_list, &pd_chan->free_list);513	pd_chan->descs_allocated = i;514	dma_cookie_init(chan);515	spin_unlock_irq(&pd_chan->lock);516 517	pdc_enable_irq(chan, 1);518 519	return pd_chan->descs_allocated;520}521 522static void pd_free_chan_resources(struct dma_chan *chan)523{524	struct pch_dma_chan *pd_chan = to_pd_chan(chan);525	struct pch_dma *pd = to_pd(chan->device);526	struct pch_dma_desc *desc, *_d;527	LIST_HEAD(tmp_list);528 529	BUG_ON(!pdc_is_idle(pd_chan));530	BUG_ON(!list_empty(&pd_chan->active_list));531	BUG_ON(!list_empty(&pd_chan->queue));532 533	spin_lock_irq(&pd_chan->lock);534	list_splice_init(&pd_chan->free_list, &tmp_list);535	pd_chan->descs_allocated = 0;536	spin_unlock_irq(&pd_chan->lock);537 538	list_for_each_entry_safe(desc, _d, &tmp_list, desc_node)539		dma_pool_free(pd->pool, desc, desc->txd.phys);540 541	pdc_enable_irq(chan, 0);542}543 544static enum dma_status pd_tx_status(struct dma_chan *chan, dma_cookie_t cookie,545				    struct dma_tx_state *txstate)546{547	return dma_cookie_status(chan, cookie, txstate);548}549 550static void pd_issue_pending(struct dma_chan *chan)551{552	struct pch_dma_chan *pd_chan = to_pd_chan(chan);553 554	if (pdc_is_idle(pd_chan)) {555		spin_lock(&pd_chan->lock);556		pdc_advance_work(pd_chan);557		spin_unlock(&pd_chan->lock);558	}559}560 561static struct dma_async_tx_descriptor *pd_prep_slave_sg(struct dma_chan *chan,562			struct scatterlist *sgl, unsigned int sg_len,563			enum dma_transfer_direction direction, unsigned long flags,564			void *context)565{566	struct pch_dma_chan *pd_chan = to_pd_chan(chan);567	struct pch_dma_slave *pd_slave = chan->private;568	struct pch_dma_desc *first = NULL;569	struct pch_dma_desc *prev = NULL;570	struct pch_dma_desc *desc = NULL;571	struct scatterlist *sg;572	dma_addr_t reg;573	int i;574 575	if (unlikely(!sg_len)) {576		dev_info(chan2dev(chan), "prep_slave_sg: length is zero!\n");577		return NULL;578	}579 580	if (direction == DMA_DEV_TO_MEM)581		reg = pd_slave->rx_reg;582	else if (direction == DMA_MEM_TO_DEV)583		reg = pd_slave->tx_reg;584	else585		return NULL;586 587	pd_chan->dir = direction;588	pdc_set_dir(chan);589 590	for_each_sg(sgl, sg, sg_len, i) {591		desc = pdc_desc_get(pd_chan);592 593		if (!desc)594			goto err_desc_get;595 596		desc->regs.dev_addr = reg;597		desc->regs.mem_addr = sg_dma_address(sg);598		desc->regs.size = sg_dma_len(sg);599		desc->regs.next = DMA_DESC_FOLLOW_WITHOUT_IRQ;600 601		switch (pd_slave->width) {602		case PCH_DMA_WIDTH_1_BYTE:603			if (desc->regs.size > DMA_DESC_MAX_COUNT_1_BYTE)604				goto err_desc_get;605			desc->regs.size |= DMA_DESC_WIDTH_1_BYTE;606			break;607		case PCH_DMA_WIDTH_2_BYTES:608			if (desc->regs.size > DMA_DESC_MAX_COUNT_2_BYTES)609				goto err_desc_get;610			desc->regs.size |= DMA_DESC_WIDTH_2_BYTES;611			break;612		case PCH_DMA_WIDTH_4_BYTES:613			if (desc->regs.size > DMA_DESC_MAX_COUNT_4_BYTES)614				goto err_desc_get;615			desc->regs.size |= DMA_DESC_WIDTH_4_BYTES;616			break;617		default:618			goto err_desc_get;619		}620 621		if (!first) {622			first = desc;623		} else {624			prev->regs.next |= desc->txd.phys;625			list_add_tail(&desc->desc_node, &first->tx_list);626		}627 628		prev = desc;629	}630 631	if (flags & DMA_PREP_INTERRUPT)632		desc->regs.next = DMA_DESC_END_WITH_IRQ;633	else634		desc->regs.next = DMA_DESC_END_WITHOUT_IRQ;635 636	first->txd.cookie = -EBUSY;637	desc->txd.flags = flags;638 639	return &first->txd;640 641err_desc_get:642	dev_err(chan2dev(chan), "failed to get desc or wrong parameters\n");643	pdc_desc_put(pd_chan, first);644	return NULL;645}646 647static int pd_device_terminate_all(struct dma_chan *chan)648{649	struct pch_dma_chan *pd_chan = to_pd_chan(chan);650	struct pch_dma_desc *desc, *_d;651	LIST_HEAD(list);652 653	spin_lock_irq(&pd_chan->lock);654 655	pdc_set_mode(&pd_chan->chan, DMA_CTL0_DISABLE);656 657	list_splice_init(&pd_chan->active_list, &list);658	list_splice_init(&pd_chan->queue, &list);659 660	list_for_each_entry_safe(desc, _d, &list, desc_node)661		pdc_chain_complete(pd_chan, desc);662 663	spin_unlock_irq(&pd_chan->lock);664 665	return 0;666}667 668static void pdc_tasklet(struct tasklet_struct *t)669{670	struct pch_dma_chan *pd_chan = from_tasklet(pd_chan, t, tasklet);671	unsigned long flags;672 673	if (!pdc_is_idle(pd_chan)) {674		dev_err(chan2dev(&pd_chan->chan),675			"BUG: handle non-idle channel in tasklet\n");676		return;677	}678 679	spin_lock_irqsave(&pd_chan->lock, flags);680	if (test_and_clear_bit(0, &pd_chan->err_status))681		pdc_handle_error(pd_chan);682	else683		pdc_advance_work(pd_chan);684	spin_unlock_irqrestore(&pd_chan->lock, flags);685}686 687static irqreturn_t pd_irq(int irq, void *devid)688{689	struct pch_dma *pd = (struct pch_dma *)devid;690	struct pch_dma_chan *pd_chan;691	u32 sts0;692	u32 sts2;693	int i;694	int ret0 = IRQ_NONE;695	int ret2 = IRQ_NONE;696 697	sts0 = dma_readl(pd, STS0);698	sts2 = dma_readl(pd, STS2);699 700	dev_dbg(pd->dma.dev, "pd_irq sts0: %x\n", sts0);701 702	for (i = 0; i < pd->dma.chancnt; i++) {703		pd_chan = &pd->channels[i];704 705		if (i < 8) {706			if (sts0 & DMA_STATUS_IRQ(i)) {707				if (sts0 & DMA_STATUS0_ERR(i))708					set_bit(0, &pd_chan->err_status);709 710				tasklet_schedule(&pd_chan->tasklet);711				ret0 = IRQ_HANDLED;712			}713		} else {714			if (sts2 & DMA_STATUS_IRQ(i - 8)) {715				if (sts2 & DMA_STATUS2_ERR(i))716					set_bit(0, &pd_chan->err_status);717 718				tasklet_schedule(&pd_chan->tasklet);719				ret2 = IRQ_HANDLED;720			}721		}722	}723 724	/* clear interrupt bits in status register */725	if (ret0)726		dma_writel(pd, STS0, sts0);727	if (ret2)728		dma_writel(pd, STS2, sts2);729 730	return ret0 | ret2;731}732 733static void __maybe_unused pch_dma_save_regs(struct pch_dma *pd)734{735	struct pch_dma_chan *pd_chan;736	struct dma_chan *chan, *_c;737	int i = 0;738 739	pd->regs.dma_ctl0 = dma_readl(pd, CTL0);740	pd->regs.dma_ctl1 = dma_readl(pd, CTL1);741	pd->regs.dma_ctl2 = dma_readl(pd, CTL2);742	pd->regs.dma_ctl3 = dma_readl(pd, CTL3);743 744	list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) {745		pd_chan = to_pd_chan(chan);746 747		pd->ch_regs[i].dev_addr = channel_readl(pd_chan, DEV_ADDR);748		pd->ch_regs[i].mem_addr = channel_readl(pd_chan, MEM_ADDR);749		pd->ch_regs[i].size = channel_readl(pd_chan, SIZE);750		pd->ch_regs[i].next = channel_readl(pd_chan, NEXT);751 752		i++;753	}754}755 756static void __maybe_unused pch_dma_restore_regs(struct pch_dma *pd)757{758	struct pch_dma_chan *pd_chan;759	struct dma_chan *chan, *_c;760	int i = 0;761 762	dma_writel(pd, CTL0, pd->regs.dma_ctl0);763	dma_writel(pd, CTL1, pd->regs.dma_ctl1);764	dma_writel(pd, CTL2, pd->regs.dma_ctl2);765	dma_writel(pd, CTL3, pd->regs.dma_ctl3);766 767	list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) {768		pd_chan = to_pd_chan(chan);769 770		channel_writel(pd_chan, DEV_ADDR, pd->ch_regs[i].dev_addr);771		channel_writel(pd_chan, MEM_ADDR, pd->ch_regs[i].mem_addr);772		channel_writel(pd_chan, SIZE, pd->ch_regs[i].size);773		channel_writel(pd_chan, NEXT, pd->ch_regs[i].next);774 775		i++;776	}777}778 779static int __maybe_unused pch_dma_suspend(struct device *dev)780{781	struct pch_dma *pd = dev_get_drvdata(dev);782 783	if (pd)784		pch_dma_save_regs(pd);785 786	return 0;787}788 789static int __maybe_unused pch_dma_resume(struct device *dev)790{791	struct pch_dma *pd = dev_get_drvdata(dev);792 793	if (pd)794		pch_dma_restore_regs(pd);795 796	return 0;797}798 799static int pch_dma_probe(struct pci_dev *pdev,800				   const struct pci_device_id *id)801{802	struct pch_dma *pd;803	struct pch_dma_regs *regs;804	unsigned int nr_channels;805	int err;806	int i;807 808	nr_channels = id->driver_data;809	pd = kzalloc(sizeof(*pd), GFP_KERNEL);810	if (!pd)811		return -ENOMEM;812 813	pci_set_drvdata(pdev, pd);814 815	err = pci_enable_device(pdev);816	if (err) {817		dev_err(&pdev->dev, "Cannot enable PCI device\n");818		goto err_free_mem;819	}820 821	if (!(pci_resource_flags(pdev, 1) & IORESOURCE_MEM)) {822		dev_err(&pdev->dev, "Cannot find proper base address\n");823		err = -ENODEV;824		goto err_disable_pdev;825	}826 827	err = pci_request_regions(pdev, DRV_NAME);828	if (err) {829		dev_err(&pdev->dev, "Cannot obtain PCI resources\n");830		goto err_disable_pdev;831	}832 833	err = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));834	if (err) {835		dev_err(&pdev->dev, "Cannot set proper DMA config\n");836		goto err_free_res;837	}838 839	regs = pd->membase = pci_iomap(pdev, 1, 0);840	if (!pd->membase) {841		dev_err(&pdev->dev, "Cannot map MMIO registers\n");842		err = -ENOMEM;843		goto err_free_res;844	}845 846	pci_set_master(pdev);847	pd->dma.dev = &pdev->dev;848 849	err = request_irq(pdev->irq, pd_irq, IRQF_SHARED, DRV_NAME, pd);850	if (err) {851		dev_err(&pdev->dev, "Failed to request IRQ\n");852		goto err_iounmap;853	}854 855	pd->pool = dma_pool_create("pch_dma_desc_pool", &pdev->dev,856				   sizeof(struct pch_dma_desc), 4, 0);857	if (!pd->pool) {858		dev_err(&pdev->dev, "Failed to alloc DMA descriptors\n");859		err = -ENOMEM;860		goto err_free_irq;861	}862 863 864	INIT_LIST_HEAD(&pd->dma.channels);865 866	for (i = 0; i < nr_channels; i++) {867		struct pch_dma_chan *pd_chan = &pd->channels[i];868 869		pd_chan->chan.device = &pd->dma;870		dma_cookie_init(&pd_chan->chan);871 872		pd_chan->membase = &regs->desc[i];873 874		spin_lock_init(&pd_chan->lock);875 876		INIT_LIST_HEAD(&pd_chan->active_list);877		INIT_LIST_HEAD(&pd_chan->queue);878		INIT_LIST_HEAD(&pd_chan->free_list);879 880		tasklet_setup(&pd_chan->tasklet, pdc_tasklet);881		list_add_tail(&pd_chan->chan.device_node, &pd->dma.channels);882	}883 884	dma_cap_zero(pd->dma.cap_mask);885	dma_cap_set(DMA_PRIVATE, pd->dma.cap_mask);886	dma_cap_set(DMA_SLAVE, pd->dma.cap_mask);887 888	pd->dma.device_alloc_chan_resources = pd_alloc_chan_resources;889	pd->dma.device_free_chan_resources = pd_free_chan_resources;890	pd->dma.device_tx_status = pd_tx_status;891	pd->dma.device_issue_pending = pd_issue_pending;892	pd->dma.device_prep_slave_sg = pd_prep_slave_sg;893	pd->dma.device_terminate_all = pd_device_terminate_all;894 895	err = dma_async_device_register(&pd->dma);896	if (err) {897		dev_err(&pdev->dev, "Failed to register DMA device\n");898		goto err_free_pool;899	}900 901	return 0;902 903err_free_pool:904	dma_pool_destroy(pd->pool);905err_free_irq:906	free_irq(pdev->irq, pd);907err_iounmap:908	pci_iounmap(pdev, pd->membase);909err_free_res:910	pci_release_regions(pdev);911err_disable_pdev:912	pci_disable_device(pdev);913err_free_mem:914	kfree(pd);915	return err;916}917 918static void pch_dma_remove(struct pci_dev *pdev)919{920	struct pch_dma *pd = pci_get_drvdata(pdev);921	struct pch_dma_chan *pd_chan;922	struct dma_chan *chan, *_c;923 924	if (pd) {925		dma_async_device_unregister(&pd->dma);926 927		free_irq(pdev->irq, pd);928 929		list_for_each_entry_safe(chan, _c, &pd->dma.channels,930					 device_node) {931			pd_chan = to_pd_chan(chan);932 933			tasklet_kill(&pd_chan->tasklet);934		}935 936		dma_pool_destroy(pd->pool);937		pci_iounmap(pdev, pd->membase);938		pci_release_regions(pdev);939		pci_disable_device(pdev);940		kfree(pd);941	}942}943 944/* PCI Device ID of DMA device */945#define PCI_DEVICE_ID_EG20T_PCH_DMA_8CH        0x8810946#define PCI_DEVICE_ID_EG20T_PCH_DMA_4CH        0x8815947#define PCI_DEVICE_ID_ML7213_DMA1_8CH	0x8026948#define PCI_DEVICE_ID_ML7213_DMA2_8CH	0x802B949#define PCI_DEVICE_ID_ML7213_DMA3_4CH	0x8034950#define PCI_DEVICE_ID_ML7213_DMA4_12CH	0x8032951#define PCI_DEVICE_ID_ML7223_DMA1_4CH	0x800B952#define PCI_DEVICE_ID_ML7223_DMA2_4CH	0x800E953#define PCI_DEVICE_ID_ML7223_DMA3_4CH	0x8017954#define PCI_DEVICE_ID_ML7223_DMA4_4CH	0x803B955#define PCI_DEVICE_ID_ML7831_DMA1_8CH	0x8810956#define PCI_DEVICE_ID_ML7831_DMA2_4CH	0x8815957 958static const struct pci_device_id pch_dma_id_table[] = {959	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_8CH), 8 },960	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_4CH), 4 },961	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA1_8CH), 8}, /* UART Video */962	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA2_8CH), 8}, /* PCMIF SPI */963	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA3_4CH), 4}, /* FPGA */964	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA4_12CH), 12}, /* I2S */965	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA1_4CH), 4}, /* UART */966	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA2_4CH), 4}, /* Video SPI */967	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA3_4CH), 4}, /* Security */968	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA4_4CH), 4}, /* FPGA */969	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_DMA1_8CH), 8}, /* UART */970	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_DMA2_4CH), 4}, /* SPI */971	{ 0, },972};973 974static SIMPLE_DEV_PM_OPS(pch_dma_pm_ops, pch_dma_suspend, pch_dma_resume);975 976static struct pci_driver pch_dma_driver = {977	.name		= DRV_NAME,978	.id_table	= pch_dma_id_table,979	.probe		= pch_dma_probe,980	.remove		= pch_dma_remove,981	.driver.pm	= &pch_dma_pm_ops,982};983 984module_pci_driver(pch_dma_driver);985 986MODULE_DESCRIPTION("Intel EG20T PCH / LAPIS Semicon ML7213/ML7223/ML7831 IOH "987		   "DMA controller driver");988MODULE_AUTHOR("Yong Wang <yong.y.wang@intel.com>");989MODULE_LICENSE("GPL v2");990MODULE_DEVICE_TABLE(pci, pch_dma_id_table);991