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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) 2014 Texas Instruments Incorporated4 * Authors:	Santosh Shilimkar <santosh.shilimkar@ti.com>5 *		Sandeep Nair <sandeep_n@ti.com>6 *		Cyril Chemparathy <cyril@ti.com>7 */8 9#include <linux/io.h>10#include <linux/sched.h>11#include <linux/module.h>12#include <linux/dma-direction.h>13#include <linux/interrupt.h>14#include <linux/pm_runtime.h>15#include <linux/of_dma.h>16#include <linux/of_address.h>17#include <linux/platform_device.h>18#include <linux/soc/ti/knav_dma.h>19#include <linux/debugfs.h>20#include <linux/seq_file.h>21 22#define REG_MASK		0xffffffff23 24#define DMA_LOOPBACK		BIT(31)25#define DMA_ENABLE		BIT(31)26#define DMA_TEARDOWN		BIT(30)27 28#define DMA_TX_FILT_PSWORDS	BIT(29)29#define DMA_TX_FILT_EINFO	BIT(30)30#define DMA_TX_PRIO_SHIFT	031#define DMA_RX_PRIO_SHIFT	1632#define DMA_PRIO_MASK		GENMASK(3, 0)33#define DMA_PRIO_DEFAULT	034#define DMA_RX_TIMEOUT_DEFAULT	17500 /* cycles */35#define DMA_RX_TIMEOUT_MASK	GENMASK(16, 0)36#define DMA_RX_TIMEOUT_SHIFT	037 38#define CHAN_HAS_EPIB		BIT(30)39#define CHAN_HAS_PSINFO		BIT(29)40#define CHAN_ERR_RETRY		BIT(28)41#define CHAN_PSINFO_AT_SOP	BIT(25)42#define CHAN_SOP_OFF_SHIFT	1643#define CHAN_SOP_OFF_MASK	GENMASK(9, 0)44#define DESC_TYPE_SHIFT		2645#define DESC_TYPE_MASK		GENMASK(2, 0)46 47/*48 * QMGR & QNUM together make up 14 bits with QMGR as the 2 MSb's in the logical49 * navigator cloud mapping scheme.50 * using the 14bit physical queue numbers directly maps into this scheme.51 */52#define CHAN_QNUM_MASK		GENMASK(14, 0)53#define DMA_MAX_QMS		454#define DMA_TIMEOUT		1	/* msecs */55#define DMA_INVALID_ID		0xffff56 57struct reg_global {58	u32	revision;59	u32	perf_control;60	u32	emulation_control;61	u32	priority_control;62	u32	qm_base_address[DMA_MAX_QMS];63};64 65struct reg_chan {66	u32	control;67	u32	mode;68	u32	__rsvd[6];69};70 71struct reg_tx_sched {72	u32	prio;73};74 75struct reg_rx_flow {76	u32	control;77	u32	tags;78	u32	tag_sel;79	u32	fdq_sel[2];80	u32	thresh[3];81};82 83struct knav_dma_pool_device {84	struct device			*dev;85	struct list_head		list;86};87 88struct knav_dma_device {89	bool				loopback, enable_all;90	unsigned			tx_priority, rx_priority, rx_timeout;91	unsigned			logical_queue_managers;92	unsigned			qm_base_address[DMA_MAX_QMS];93	struct reg_global __iomem	*reg_global;94	struct reg_chan __iomem		*reg_tx_chan;95	struct reg_rx_flow __iomem	*reg_rx_flow;96	struct reg_chan __iomem		*reg_rx_chan;97	struct reg_tx_sched __iomem	*reg_tx_sched;98	unsigned			max_rx_chan, max_tx_chan;99	unsigned			max_rx_flow;100	char				name[32];101	atomic_t			ref_count;102	struct list_head		list;103	struct list_head		chan_list;104	spinlock_t			lock;105};106 107struct knav_dma_chan {108	enum dma_transfer_direction	direction;109	struct knav_dma_device		*dma;110	atomic_t			ref_count;111 112	/* registers */113	struct reg_chan __iomem		*reg_chan;114	struct reg_tx_sched __iomem	*reg_tx_sched;115	struct reg_rx_flow __iomem	*reg_rx_flow;116 117	/* configuration stuff */118	unsigned			channel, flow;119	struct knav_dma_cfg		cfg;120	struct list_head		list;121	spinlock_t			lock;122};123 124#define chan_number(ch)	((ch->direction == DMA_MEM_TO_DEV) ? \125			ch->channel : ch->flow)126 127static struct knav_dma_pool_device *kdev;128 129static bool device_ready;130bool knav_dma_device_ready(void)131{132	return device_ready;133}134EXPORT_SYMBOL_GPL(knav_dma_device_ready);135 136static bool check_config(struct knav_dma_chan *chan, struct knav_dma_cfg *cfg)137{138	if (!memcmp(&chan->cfg, cfg, sizeof(*cfg)))139		return true;140	else141		return false;142}143 144static int chan_start(struct knav_dma_chan *chan,145			struct knav_dma_cfg *cfg)146{147	u32 v = 0;148 149	spin_lock(&chan->lock);150	if ((chan->direction == DMA_MEM_TO_DEV) && chan->reg_chan) {151		if (cfg->u.tx.filt_pswords)152			v |= DMA_TX_FILT_PSWORDS;153		if (cfg->u.tx.filt_einfo)154			v |= DMA_TX_FILT_EINFO;155		writel_relaxed(v, &chan->reg_chan->mode);156		writel_relaxed(DMA_ENABLE, &chan->reg_chan->control);157	}158 159	if (chan->reg_tx_sched)160		writel_relaxed(cfg->u.tx.priority, &chan->reg_tx_sched->prio);161 162	if (chan->reg_rx_flow) {163		v = 0;164 165		if (cfg->u.rx.einfo_present)166			v |= CHAN_HAS_EPIB;167		if (cfg->u.rx.psinfo_present)168			v |= CHAN_HAS_PSINFO;169		if (cfg->u.rx.err_mode == DMA_RETRY)170			v |= CHAN_ERR_RETRY;171		v |= (cfg->u.rx.desc_type & DESC_TYPE_MASK) << DESC_TYPE_SHIFT;172		if (cfg->u.rx.psinfo_at_sop)173			v |= CHAN_PSINFO_AT_SOP;174		v |= (cfg->u.rx.sop_offset & CHAN_SOP_OFF_MASK)175			<< CHAN_SOP_OFF_SHIFT;176		v |= cfg->u.rx.dst_q & CHAN_QNUM_MASK;177 178		writel_relaxed(v, &chan->reg_rx_flow->control);179		writel_relaxed(0, &chan->reg_rx_flow->tags);180		writel_relaxed(0, &chan->reg_rx_flow->tag_sel);181 182		v =  cfg->u.rx.fdq[0] << 16;183		v |=  cfg->u.rx.fdq[1] & CHAN_QNUM_MASK;184		writel_relaxed(v, &chan->reg_rx_flow->fdq_sel[0]);185 186		v =  cfg->u.rx.fdq[2] << 16;187		v |=  cfg->u.rx.fdq[3] & CHAN_QNUM_MASK;188		writel_relaxed(v, &chan->reg_rx_flow->fdq_sel[1]);189 190		writel_relaxed(0, &chan->reg_rx_flow->thresh[0]);191		writel_relaxed(0, &chan->reg_rx_flow->thresh[1]);192		writel_relaxed(0, &chan->reg_rx_flow->thresh[2]);193	}194 195	/* Keep a copy of the cfg */196	memcpy(&chan->cfg, cfg, sizeof(*cfg));197	spin_unlock(&chan->lock);198 199	return 0;200}201 202static int chan_teardown(struct knav_dma_chan *chan)203{204	unsigned long end, value;205 206	if (!chan->reg_chan)207		return 0;208 209	/* indicate teardown */210	writel_relaxed(DMA_TEARDOWN, &chan->reg_chan->control);211 212	/* wait for the dma to shut itself down */213	end = jiffies + msecs_to_jiffies(DMA_TIMEOUT);214	do {215		value = readl_relaxed(&chan->reg_chan->control);216		if ((value & DMA_ENABLE) == 0)217			break;218	} while (time_after(end, jiffies));219 220	if (readl_relaxed(&chan->reg_chan->control) & DMA_ENABLE) {221		dev_err(kdev->dev, "timeout waiting for teardown\n");222		return -ETIMEDOUT;223	}224 225	return 0;226}227 228static void chan_stop(struct knav_dma_chan *chan)229{230	spin_lock(&chan->lock);231	if (chan->reg_rx_flow) {232		/* first detach fdqs, starve out the flow */233		writel_relaxed(0, &chan->reg_rx_flow->fdq_sel[0]);234		writel_relaxed(0, &chan->reg_rx_flow->fdq_sel[1]);235		writel_relaxed(0, &chan->reg_rx_flow->thresh[0]);236		writel_relaxed(0, &chan->reg_rx_flow->thresh[1]);237		writel_relaxed(0, &chan->reg_rx_flow->thresh[2]);238	}239 240	/* teardown the dma channel */241	chan_teardown(chan);242 243	/* then disconnect the completion side */244	if (chan->reg_rx_flow) {245		writel_relaxed(0, &chan->reg_rx_flow->control);246		writel_relaxed(0, &chan->reg_rx_flow->tags);247		writel_relaxed(0, &chan->reg_rx_flow->tag_sel);248	}249 250	memset(&chan->cfg, 0, sizeof(struct knav_dma_cfg));251	spin_unlock(&chan->lock);252 253	dev_dbg(kdev->dev, "channel stopped\n");254}255 256static void dma_hw_enable_all(struct knav_dma_device *dma)257{258	int i;259 260	for (i = 0; i < dma->max_tx_chan; i++) {261		writel_relaxed(0, &dma->reg_tx_chan[i].mode);262		writel_relaxed(DMA_ENABLE, &dma->reg_tx_chan[i].control);263	}264}265 266 267static void knav_dma_hw_init(struct knav_dma_device *dma)268{269	unsigned v;270	int i;271 272	spin_lock(&dma->lock);273	v  = dma->loopback ? DMA_LOOPBACK : 0;274	writel_relaxed(v, &dma->reg_global->emulation_control);275 276	v = readl_relaxed(&dma->reg_global->perf_control);277	v |= ((dma->rx_timeout & DMA_RX_TIMEOUT_MASK) << DMA_RX_TIMEOUT_SHIFT);278	writel_relaxed(v, &dma->reg_global->perf_control);279 280	v = ((dma->tx_priority << DMA_TX_PRIO_SHIFT) |281	     (dma->rx_priority << DMA_RX_PRIO_SHIFT));282 283	writel_relaxed(v, &dma->reg_global->priority_control);284 285	/* Always enable all Rx channels. Rx paths are managed using flows */286	for (i = 0; i < dma->max_rx_chan; i++)287		writel_relaxed(DMA_ENABLE, &dma->reg_rx_chan[i].control);288 289	for (i = 0; i < dma->logical_queue_managers; i++)290		writel_relaxed(dma->qm_base_address[i],291			       &dma->reg_global->qm_base_address[i]);292	spin_unlock(&dma->lock);293}294 295static void knav_dma_hw_destroy(struct knav_dma_device *dma)296{297	int i;298	unsigned v;299 300	spin_lock(&dma->lock);301	v = ~DMA_ENABLE & REG_MASK;302 303	for (i = 0; i < dma->max_rx_chan; i++)304		writel_relaxed(v, &dma->reg_rx_chan[i].control);305 306	for (i = 0; i < dma->max_tx_chan; i++)307		writel_relaxed(v, &dma->reg_tx_chan[i].control);308	spin_unlock(&dma->lock);309}310 311static void dma_debug_show_channels(struct seq_file *s,312					struct knav_dma_chan *chan)313{314	int i;315 316	seq_printf(s, "\t%s %d:\t",317		((chan->direction == DMA_MEM_TO_DEV) ? "tx chan" : "rx flow"),318		chan_number(chan));319 320	if (chan->direction == DMA_MEM_TO_DEV) {321		seq_printf(s, "einfo - %d, pswords - %d, priority - %d\n",322			chan->cfg.u.tx.filt_einfo,323			chan->cfg.u.tx.filt_pswords,324			chan->cfg.u.tx.priority);325	} else {326		seq_printf(s, "einfo - %d, psinfo - %d, desc_type - %d\n",327			chan->cfg.u.rx.einfo_present,328			chan->cfg.u.rx.psinfo_present,329			chan->cfg.u.rx.desc_type);330		seq_printf(s, "\t\t\tdst_q: [%d], thresh: %d fdq: ",331			chan->cfg.u.rx.dst_q,332			chan->cfg.u.rx.thresh);333		for (i = 0; i < KNAV_DMA_FDQ_PER_CHAN; i++)334			seq_printf(s, "[%d]", chan->cfg.u.rx.fdq[i]);335		seq_printf(s, "\n");336	}337}338 339static void dma_debug_show_devices(struct seq_file *s,340					struct knav_dma_device *dma)341{342	struct knav_dma_chan *chan;343 344	list_for_each_entry(chan, &dma->chan_list, list) {345		if (atomic_read(&chan->ref_count))346			dma_debug_show_channels(s, chan);347	}348}349 350static int knav_dma_debug_show(struct seq_file *s, void *v)351{352	struct knav_dma_device *dma;353 354	list_for_each_entry(dma, &kdev->list, list) {355		if (atomic_read(&dma->ref_count)) {356			seq_printf(s, "%s : max_tx_chan: (%d), max_rx_flows: (%d)\n",357			dma->name, dma->max_tx_chan, dma->max_rx_flow);358			dma_debug_show_devices(s, dma);359		}360	}361 362	return 0;363}364 365DEFINE_SHOW_ATTRIBUTE(knav_dma_debug);366 367static int of_channel_match_helper(struct device_node *np, const char *name,368					const char **dma_instance)369{370	struct of_phandle_args args;371	struct device_node *dma_node;372	int index;373 374	dma_node = of_parse_phandle(np, "ti,navigator-dmas", 0);375	if (!dma_node)376		return -ENODEV;377 378	*dma_instance = dma_node->name;379	index = of_property_match_string(np, "ti,navigator-dma-names", name);380	if (index < 0) {381		dev_err(kdev->dev, "No 'ti,navigator-dma-names' property\n");382		return -ENODEV;383	}384 385	if (of_parse_phandle_with_fixed_args(np, "ti,navigator-dmas",386					1, index, &args)) {387		dev_err(kdev->dev, "Missing the phandle args name %s\n", name);388		return -ENODEV;389	}390 391	if (args.args[0] < 0) {392		dev_err(kdev->dev, "Missing args for %s\n", name);393		return -ENODEV;394	}395 396	return args.args[0];397}398 399/**400 * knav_dma_open_channel() - try to setup an exclusive slave channel401 * @dev:	pointer to client device structure402 * @name:	slave channel name403 * @config:	dma configuration parameters404 *405 * Returns pointer to appropriate DMA channel on success or error.406 */407void *knav_dma_open_channel(struct device *dev, const char *name,408					struct knav_dma_cfg *config)409{410	struct knav_dma_device *dma = NULL, *iter1;411	struct knav_dma_chan *chan = NULL, *iter2;412	int chan_num = -1;413	const char *instance;414 415	if (!kdev) {416		pr_err("keystone-navigator-dma driver not registered\n");417		return (void *)-EINVAL;418	}419 420	chan_num = of_channel_match_helper(dev->of_node, name, &instance);421	if (chan_num < 0) {422		dev_err(kdev->dev, "No DMA instance with name %s\n", name);423		return (void *)-EINVAL;424	}425 426	dev_dbg(kdev->dev, "initializing %s channel %d from DMA %s\n",427		  config->direction == DMA_MEM_TO_DEV ? "transmit" :428		  config->direction == DMA_DEV_TO_MEM ? "receive"  :429		  "unknown", chan_num, instance);430 431	if (config->direction != DMA_MEM_TO_DEV &&432	    config->direction != DMA_DEV_TO_MEM) {433		dev_err(kdev->dev, "bad direction\n");434		return (void *)-EINVAL;435	}436 437	/* Look for correct dma instance */438	list_for_each_entry(iter1, &kdev->list, list) {439		if (!strcmp(iter1->name, instance)) {440			dma = iter1;441			break;442		}443	}444	if (!dma) {445		dev_err(kdev->dev, "No DMA instance with name %s\n", instance);446		return (void *)-EINVAL;447	}448 449	/* Look for correct dma channel from dma instance */450	list_for_each_entry(iter2, &dma->chan_list, list) {451		if (config->direction == DMA_MEM_TO_DEV) {452			if (iter2->channel == chan_num) {453				chan = iter2;454				break;455			}456		} else {457			if (iter2->flow == chan_num) {458				chan = iter2;459				break;460			}461		}462	}463	if (!chan) {464		dev_err(kdev->dev, "channel %d is not in DMA %s\n",465				chan_num, instance);466		return (void *)-EINVAL;467	}468 469	if (atomic_read(&chan->ref_count) >= 1) {470		if (!check_config(chan, config)) {471			dev_err(kdev->dev, "channel %d config miss-match\n",472				chan_num);473			return (void *)-EINVAL;474		}475	}476 477	if (atomic_inc_return(&chan->dma->ref_count) <= 1)478		knav_dma_hw_init(chan->dma);479 480	if (atomic_inc_return(&chan->ref_count) <= 1)481		chan_start(chan, config);482 483	dev_dbg(kdev->dev, "channel %d opened from DMA %s\n",484				chan_num, instance);485 486	return chan;487}488EXPORT_SYMBOL_GPL(knav_dma_open_channel);489 490/**491 * knav_dma_close_channel()	- Destroy a dma channel492 *493 * @channel:	dma channel handle494 *495 */496void knav_dma_close_channel(void *channel)497{498	struct knav_dma_chan *chan = channel;499 500	if (!kdev) {501		pr_err("keystone-navigator-dma driver not registered\n");502		return;503	}504 505	if (atomic_dec_return(&chan->ref_count) <= 0)506		chan_stop(chan);507 508	if (atomic_dec_return(&chan->dma->ref_count) <= 0)509		knav_dma_hw_destroy(chan->dma);510 511	dev_dbg(kdev->dev, "channel %d or flow %d closed from DMA %s\n",512			chan->channel, chan->flow, chan->dma->name);513}514EXPORT_SYMBOL_GPL(knav_dma_close_channel);515 516static void __iomem *pktdma_get_regs(struct knav_dma_device *dma,517				struct device_node *node,518				unsigned index, resource_size_t *_size)519{520	struct device *dev = kdev->dev;521	struct resource res;522	void __iomem *regs;523	int ret;524 525	ret = of_address_to_resource(node, index, &res);526	if (ret) {527		dev_err(dev, "Can't translate of node(%pOFn) address for index(%d)\n",528			node, index);529		return ERR_PTR(ret);530	}531 532	regs = devm_ioremap_resource(kdev->dev, &res);533	if (IS_ERR(regs))534		dev_err(dev, "Failed to map register base for index(%d) node(%pOFn)\n",535			index, node);536	if (_size)537		*_size = resource_size(&res);538 539	return regs;540}541 542static int pktdma_init_rx_chan(struct knav_dma_chan *chan, u32 flow)543{544	struct knav_dma_device *dma = chan->dma;545 546	chan->flow = flow;547	chan->reg_rx_flow = dma->reg_rx_flow + flow;548	chan->channel = DMA_INVALID_ID;549	dev_dbg(kdev->dev, "rx flow(%d) (%p)\n", chan->flow, chan->reg_rx_flow);550 551	return 0;552}553 554static int pktdma_init_tx_chan(struct knav_dma_chan *chan, u32 channel)555{556	struct knav_dma_device *dma = chan->dma;557 558	chan->channel = channel;559	chan->reg_chan = dma->reg_tx_chan + channel;560	chan->reg_tx_sched = dma->reg_tx_sched + channel;561	chan->flow = DMA_INVALID_ID;562	dev_dbg(kdev->dev, "tx channel(%d) (%p)\n", chan->channel, chan->reg_chan);563 564	return 0;565}566 567static int pktdma_init_chan(struct knav_dma_device *dma,568				enum dma_transfer_direction dir,569				unsigned chan_num)570{571	struct device *dev = kdev->dev;572	struct knav_dma_chan *chan;573	int ret = -EINVAL;574 575	chan = devm_kzalloc(dev, sizeof(*chan), GFP_KERNEL);576	if (!chan)577		return -ENOMEM;578 579	INIT_LIST_HEAD(&chan->list);580	chan->dma	= dma;581	chan->direction	= DMA_TRANS_NONE;582	atomic_set(&chan->ref_count, 0);583	spin_lock_init(&chan->lock);584 585	if (dir == DMA_MEM_TO_DEV) {586		chan->direction = dir;587		ret = pktdma_init_tx_chan(chan, chan_num);588	} else if (dir == DMA_DEV_TO_MEM) {589		chan->direction = dir;590		ret = pktdma_init_rx_chan(chan, chan_num);591	} else {592		dev_err(dev, "channel(%d) direction unknown\n", chan_num);593	}594 595	list_add_tail(&chan->list, &dma->chan_list);596 597	return ret;598}599 600static int dma_init(struct device_node *cloud, struct device_node *dma_node)601{602	unsigned max_tx_chan, max_rx_chan, max_rx_flow, max_tx_sched;603	struct device_node *node = dma_node;604	struct knav_dma_device *dma;605	int ret, num_chan = 0;606	resource_size_t size;607	u32 timeout;608	u32 i;609 610	dma = devm_kzalloc(kdev->dev, sizeof(*dma), GFP_KERNEL);611	if (!dma) {612		dev_err(kdev->dev, "could not allocate driver mem\n");613		return -ENOMEM;614	}615	INIT_LIST_HEAD(&dma->list);616	INIT_LIST_HEAD(&dma->chan_list);617 618	ret = of_property_read_variable_u32_array(cloud, "ti,navigator-cloud-address",619						  dma->qm_base_address, 1, DMA_MAX_QMS);620	if (ret < 0) {621		dev_err(kdev->dev, "invalid navigator cloud addresses\n");622		return -ENODEV;623	}624	dma->logical_queue_managers = ret;625 626	dma->reg_global	 = pktdma_get_regs(dma, node, 0, &size);627	if (IS_ERR(dma->reg_global))628		return PTR_ERR(dma->reg_global);629	if (size < sizeof(struct reg_global)) {630		dev_err(kdev->dev, "bad size %pa for global regs\n", &size);631		return -ENODEV;632	}633 634	dma->reg_tx_chan = pktdma_get_regs(dma, node, 1, &size);635	if (IS_ERR(dma->reg_tx_chan))636		return PTR_ERR(dma->reg_tx_chan);637 638	max_tx_chan = size / sizeof(struct reg_chan);639	dma->reg_rx_chan = pktdma_get_regs(dma, node, 2, &size);640	if (IS_ERR(dma->reg_rx_chan))641		return PTR_ERR(dma->reg_rx_chan);642 643	max_rx_chan = size / sizeof(struct reg_chan);644	dma->reg_tx_sched = pktdma_get_regs(dma, node, 3, &size);645	if (IS_ERR(dma->reg_tx_sched))646		return PTR_ERR(dma->reg_tx_sched);647 648	max_tx_sched = size / sizeof(struct reg_tx_sched);649	dma->reg_rx_flow = pktdma_get_regs(dma, node, 4, &size);650	if (IS_ERR(dma->reg_rx_flow))651		return PTR_ERR(dma->reg_rx_flow);652 653	max_rx_flow = size / sizeof(struct reg_rx_flow);654	dma->rx_priority = DMA_PRIO_DEFAULT;655	dma->tx_priority = DMA_PRIO_DEFAULT;656 657	dma->enable_all	= of_property_read_bool(node, "ti,enable-all");658	dma->loopback	= of_property_read_bool(node, "ti,loop-back");659 660	ret = of_property_read_u32(node, "ti,rx-retry-timeout", &timeout);661	if (ret < 0) {662		dev_dbg(kdev->dev, "unspecified rx timeout using value %d\n",663			DMA_RX_TIMEOUT_DEFAULT);664		timeout = DMA_RX_TIMEOUT_DEFAULT;665	}666 667	dma->rx_timeout = timeout;668	dma->max_rx_chan = max_rx_chan;669	dma->max_rx_flow = max_rx_flow;670	dma->max_tx_chan = min(max_tx_chan, max_tx_sched);671	atomic_set(&dma->ref_count, 0);672	strcpy(dma->name, node->name);673	spin_lock_init(&dma->lock);674 675	for (i = 0; i < dma->max_tx_chan; i++) {676		if (pktdma_init_chan(dma, DMA_MEM_TO_DEV, i) >= 0)677			num_chan++;678	}679 680	for (i = 0; i < dma->max_rx_flow; i++) {681		if (pktdma_init_chan(dma, DMA_DEV_TO_MEM, i) >= 0)682			num_chan++;683	}684 685	list_add_tail(&dma->list, &kdev->list);686 687	/*688	 * For DSP software usecases or userpace transport software, setup all689	 * the DMA hardware resources.690	 */691	if (dma->enable_all) {692		atomic_inc(&dma->ref_count);693		knav_dma_hw_init(dma);694		dma_hw_enable_all(dma);695	}696 697	dev_info(kdev->dev, "DMA %s registered %d logical channels, flows %d, tx chans: %d, rx chans: %d%s\n",698		dma->name, num_chan, dma->max_rx_flow,699		dma->max_tx_chan, dma->max_rx_chan,700		dma->loopback ? ", loopback" : "");701 702	return 0;703}704 705static int knav_dma_probe(struct platform_device *pdev)706{707	struct device *dev = &pdev->dev;708	struct device_node *node = pdev->dev.of_node;709	struct device_node *child;710	int ret = 0;711 712	if (!node) {713		dev_err(&pdev->dev, "could not find device info\n");714		return -EINVAL;715	}716 717	kdev = devm_kzalloc(dev,718			sizeof(struct knav_dma_pool_device), GFP_KERNEL);719	if (!kdev) {720		dev_err(dev, "could not allocate driver mem\n");721		return -ENOMEM;722	}723 724	kdev->dev = dev;725	INIT_LIST_HEAD(&kdev->list);726 727	pm_runtime_enable(kdev->dev);728	ret = pm_runtime_resume_and_get(kdev->dev);729	if (ret < 0) {730		dev_err(kdev->dev, "unable to enable pktdma, err %d\n", ret);731		goto err_pm_disable;732	}733 734	/* Initialise all packet dmas */735	for_each_child_of_node(node, child) {736		ret = dma_init(node, child);737		if (ret) {738			of_node_put(child);739			dev_err(&pdev->dev, "init failed with %d\n", ret);740			break;741		}742	}743 744	if (list_empty(&kdev->list)) {745		dev_err(dev, "no valid dma instance\n");746		ret = -ENODEV;747		goto err_put_sync;748	}749 750	debugfs_create_file("knav_dma", S_IFREG | S_IRUGO, NULL, NULL,751			    &knav_dma_debug_fops);752 753	device_ready = true;754	return ret;755 756err_put_sync:757	pm_runtime_put_sync(kdev->dev);758err_pm_disable:759	pm_runtime_disable(kdev->dev);760 761	return ret;762}763 764static void knav_dma_remove(struct platform_device *pdev)765{766	struct knav_dma_device *dma;767 768	list_for_each_entry(dma, &kdev->list, list) {769		if (atomic_dec_return(&dma->ref_count) == 0)770			knav_dma_hw_destroy(dma);771	}772 773	pm_runtime_put_sync(&pdev->dev);774	pm_runtime_disable(&pdev->dev);775}776 777static struct of_device_id of_match[] = {778	{ .compatible = "ti,keystone-navigator-dma", },779	{},780};781 782MODULE_DEVICE_TABLE(of, of_match);783 784static struct platform_driver knav_dma_driver = {785	.probe	= knav_dma_probe,786	.remove_new = knav_dma_remove,787	.driver = {788		.name		= "keystone-navigator-dma",789		.of_match_table	= of_match,790	},791};792module_platform_driver(knav_dma_driver);793 794MODULE_LICENSE("GPL v2");795MODULE_DESCRIPTION("TI Keystone Navigator Packet DMA driver");796MODULE_AUTHOR("Sandeep Nair <sandeep_n@ti.com>");797MODULE_AUTHOR("Santosh Shilimkar <santosh.shilimkar@ti.com>");798