Initial import

1 files changed, 814 insertions, 0 deletions

diff --git a/drivers/soc/ti/knav_dma.c b/drivers/soc/ti/knav_dma.c
new file mode 100644
index 000000000..bc1b80ec6
--- /dev/null
+++ b/drivers/soc/ti/knav_dma.c
@@ -0,0 +1,814 @@
+/*
+ * Copyright (C) 2014 Texas Instruments Incorporated
+ * Authors:	Santosh Shilimkar <santosh.shilimkar@ti.com>
+ *		Sandeep Nair <sandeep_n@ti.com>
+ *		Cyril Chemparathy <cyril@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/io.h>
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <linux/dma-direction.h>
+#include <linux/interrupt.h>
+#include <linux/pm_runtime.h>
+#include <linux/of_dma.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/soc/ti/knav_dma.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+#define REG_MASK		0xffffffff
+
+#define DMA_LOOPBACK		BIT(31)
+#define DMA_ENABLE		BIT(31)
+#define DMA_TEARDOWN		BIT(30)
+
+#define DMA_TX_FILT_PSWORDS	BIT(29)
+#define DMA_TX_FILT_EINFO	BIT(30)
+#define DMA_TX_PRIO_SHIFT	0
+#define DMA_RX_PRIO_SHIFT	16
+#define DMA_PRIO_MASK		GENMASK(3, 0)
+#define DMA_PRIO_DEFAULT	0
+#define DMA_RX_TIMEOUT_DEFAULT	17500 /* cycles */
+#define DMA_RX_TIMEOUT_MASK	GENMASK(16, 0)
+#define DMA_RX_TIMEOUT_SHIFT	0
+
+#define CHAN_HAS_EPIB		BIT(30)
+#define CHAN_HAS_PSINFO		BIT(29)
+#define CHAN_ERR_RETRY		BIT(28)
+#define CHAN_PSINFO_AT_SOP	BIT(25)
+#define CHAN_SOP_OFF_SHIFT	16
+#define CHAN_SOP_OFF_MASK	GENMASK(9, 0)
+#define DESC_TYPE_SHIFT		26
+#define DESC_TYPE_MASK		GENMASK(2, 0)
+
+/*
+ * QMGR & QNUM together make up 14 bits with QMGR as the 2 MSb's in the logical
+ * navigator cloud mapping scheme.
+ * using the 14bit physical queue numbers directly maps into this scheme.
+ */
+#define CHAN_QNUM_MASK		GENMASK(14, 0)
+#define DMA_MAX_QMS		4
+#define DMA_TIMEOUT		1	/* msecs */
+#define DMA_INVALID_ID		0xffff
+
+struct reg_global {
+	u32	revision;
+	u32	perf_control;
+	u32	emulation_control;
+	u32	priority_control;
+	u32	qm_base_address[DMA_MAX_QMS];
+};
+
+struct reg_chan {
+	u32	control;
+	u32	mode;
+	u32	__rsvd[6];
+};
+
+struct reg_tx_sched {
+	u32	prio;
+};
+
+struct reg_rx_flow {
+	u32	control;
+	u32	tags;
+	u32	tag_sel;
+	u32	fdq_sel[2];
+	u32	thresh[3];
+};
+
+struct knav_dma_pool_device {
+	struct device			*dev;
+	struct list_head		list;
+};
+
+struct knav_dma_device {
+	bool				loopback, enable_all;
+	unsigned			tx_priority, rx_priority, rx_timeout;
+	unsigned			logical_queue_managers;
+	unsigned			qm_base_address[DMA_MAX_QMS];
+	struct reg_global __iomem	*reg_global;
+	struct reg_chan __iomem		*reg_tx_chan;
+	struct reg_rx_flow __iomem	*reg_rx_flow;
+	struct reg_chan __iomem		*reg_rx_chan;
+	struct reg_tx_sched __iomem	*reg_tx_sched;
+	unsigned			max_rx_chan, max_tx_chan;
+	unsigned			max_rx_flow;
+	char				name[32];
+	atomic_t			ref_count;
+	struct list_head		list;
+	struct list_head		chan_list;
+	spinlock_t			lock;
+};
+
+struct knav_dma_chan {
+	enum dma_transfer_direction	direction;
+	struct knav_dma_device		*dma;
+	atomic_t			ref_count;
+
+	/* registers */
+	struct reg_chan __iomem		*reg_chan;
+	struct reg_tx_sched __iomem	*reg_tx_sched;
+	struct reg_rx_flow __iomem	*reg_rx_flow;
+
+	/* configuration stuff */
+	unsigned			channel, flow;
+	struct knav_dma_cfg		cfg;
+	struct list_head		list;
+	spinlock_t			lock;
+};
+
+#define chan_number(ch)	((ch->direction == DMA_MEM_TO_DEV) ? \
+			ch->channel : ch->flow)
+
+static struct knav_dma_pool_device *kdev;
+
+static bool check_config(struct knav_dma_chan *chan, struct knav_dma_cfg *cfg)
+{
+	if (!memcmp(&chan->cfg, cfg, sizeof(*cfg)))
+		return true;
+	else
+		return false;
+}
+
+static int chan_start(struct knav_dma_chan *chan,
+			struct knav_dma_cfg *cfg)
+{
+	u32 v = 0;
+
+	spin_lock(&chan->lock);
+	if ((chan->direction == DMA_MEM_TO_DEV) && chan->reg_chan) {
+		if (cfg->u.tx.filt_pswords)
+			v |= DMA_TX_FILT_PSWORDS;
+		if (cfg->u.tx.filt_einfo)
+			v |= DMA_TX_FILT_EINFO;
+		writel_relaxed(v, &chan->reg_chan->mode);
+		writel_relaxed(DMA_ENABLE, &chan->reg_chan->control);
+	}
+
+	if (chan->reg_tx_sched)
+		writel_relaxed(cfg->u.tx.priority, &chan->reg_tx_sched->prio);
+
+	if (chan->reg_rx_flow) {
+		v = 0;
+
+		if (cfg->u.rx.einfo_present)
+			v |= CHAN_HAS_EPIB;
+		if (cfg->u.rx.psinfo_present)
+			v |= CHAN_HAS_PSINFO;
+		if (cfg->u.rx.err_mode == DMA_RETRY)
+			v |= CHAN_ERR_RETRY;
+		v |= (cfg->u.rx.desc_type & DESC_TYPE_MASK) << DESC_TYPE_SHIFT;
+		if (cfg->u.rx.psinfo_at_sop)
+			v |= CHAN_PSINFO_AT_SOP;
+		v |= (cfg->u.rx.sop_offset & CHAN_SOP_OFF_MASK)
+			<< CHAN_SOP_OFF_SHIFT;
+		v |= cfg->u.rx.dst_q & CHAN_QNUM_MASK;
+
+		writel_relaxed(v, &chan->reg_rx_flow->control);
+		writel_relaxed(0, &chan->reg_rx_flow->tags);
+		writel_relaxed(0, &chan->reg_rx_flow->tag_sel);
+
+		v =  cfg->u.rx.fdq[0] << 16;
+		v |=  cfg->u.rx.fdq[1] & CHAN_QNUM_MASK;
+		writel_relaxed(v, &chan->reg_rx_flow->fdq_sel[0]);
+
+		v =  cfg->u.rx.fdq[2] << 16;
+		v |=  cfg->u.rx.fdq[3] & CHAN_QNUM_MASK;
+		writel_relaxed(v, &chan->reg_rx_flow->fdq_sel[1]);
+
+		writel_relaxed(0, &chan->reg_rx_flow->thresh[0]);
+		writel_relaxed(0, &chan->reg_rx_flow->thresh[1]);
+		writel_relaxed(0, &chan->reg_rx_flow->thresh[2]);
+	}
+
+	/* Keep a copy of the cfg */
+	memcpy(&chan->cfg, cfg, sizeof(*cfg));
+	spin_unlock(&chan->lock);
+
+	return 0;
+}
+
+static int chan_teardown(struct knav_dma_chan *chan)
+{
+	unsigned long end, value;
+
+	if (!chan->reg_chan)
+		return 0;
+
+	/* indicate teardown */
+	writel_relaxed(DMA_TEARDOWN, &chan->reg_chan->control);
+
+	/* wait for the dma to shut itself down */
+	end = jiffies + msecs_to_jiffies(DMA_TIMEOUT);
+	do {
+		value = readl_relaxed(&chan->reg_chan->control);
+		if ((value & DMA_ENABLE) == 0)
+			break;
+	} while (time_after(end, jiffies));
+
+	if (readl_relaxed(&chan->reg_chan->control) & DMA_ENABLE) {
+		dev_err(kdev->dev, "timeout waiting for teardown\n");
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+static void chan_stop(struct knav_dma_chan *chan)
+{
+	spin_lock(&chan->lock);
+	if (chan->reg_rx_flow) {
+		/* first detach fdqs, starve out the flow */
+		writel_relaxed(0, &chan->reg_rx_flow->fdq_sel[0]);
+		writel_relaxed(0, &chan->reg_rx_flow->fdq_sel[1]);
+		writel_relaxed(0, &chan->reg_rx_flow->thresh[0]);
+		writel_relaxed(0, &chan->reg_rx_flow->thresh[1]);
+		writel_relaxed(0, &chan->reg_rx_flow->thresh[2]);
+	}
+
+	/* teardown the dma channel */
+	chan_teardown(chan);
+
+	/* then disconnect the completion side */
+	if (chan->reg_rx_flow) {
+		writel_relaxed(0, &chan->reg_rx_flow->control);
+		writel_relaxed(0, &chan->reg_rx_flow->tags);
+		writel_relaxed(0, &chan->reg_rx_flow->tag_sel);
+	}
+
+	memset(&chan->cfg, 0, sizeof(struct knav_dma_cfg));
+	spin_unlock(&chan->lock);
+
+	dev_dbg(kdev->dev, "channel stopped\n");
+}
+
+static void dma_hw_enable_all(struct knav_dma_device *dma)
+{
+	int i;
+
+	for (i = 0; i < dma->max_tx_chan; i++) {
+		writel_relaxed(0, &dma->reg_tx_chan[i].mode);
+		writel_relaxed(DMA_ENABLE, &dma->reg_tx_chan[i].control);
+	}
+}
+
+
+static void knav_dma_hw_init(struct knav_dma_device *dma)
+{
+	unsigned v;
+	int i;
+
+	spin_lock(&dma->lock);
+	v  = dma->loopback ? DMA_LOOPBACK : 0;
+	writel_relaxed(v, &dma->reg_global->emulation_control);
+
+	v = readl_relaxed(&dma->reg_global->perf_control);
+	v |= ((dma->rx_timeout & DMA_RX_TIMEOUT_MASK) << DMA_RX_TIMEOUT_SHIFT);
+	writel_relaxed(v, &dma->reg_global->perf_control);
+
+	v = ((dma->tx_priority << DMA_TX_PRIO_SHIFT) |
+	     (dma->rx_priority << DMA_RX_PRIO_SHIFT));
+
+	writel_relaxed(v, &dma->reg_global->priority_control);
+
+	/* Always enable all Rx channels. Rx paths are managed using flows */
+	for (i = 0; i < dma->max_rx_chan; i++)
+		writel_relaxed(DMA_ENABLE, &dma->reg_rx_chan[i].control);
+
+	for (i = 0; i < dma->logical_queue_managers; i++)
+		writel_relaxed(dma->qm_base_address[i],
+			       &dma->reg_global->qm_base_address[i]);
+	spin_unlock(&dma->lock);
+}
+
+static void knav_dma_hw_destroy(struct knav_dma_device *dma)
+{
+	int i;
+	unsigned v;
+
+	spin_lock(&dma->lock);
+	v = ~DMA_ENABLE & REG_MASK;
+
+	for (i = 0; i < dma->max_rx_chan; i++)
+		writel_relaxed(v, &dma->reg_rx_chan[i].control);
+
+	for (i = 0; i < dma->max_tx_chan; i++)
+		writel_relaxed(v, &dma->reg_tx_chan[i].control);
+	spin_unlock(&dma->lock);
+}
+
+static void dma_debug_show_channels(struct seq_file *s,
+					struct knav_dma_chan *chan)
+{
+	int i;
+
+	seq_printf(s, "\t%s %d:\t",
+		((chan->direction == DMA_MEM_TO_DEV) ? "tx chan" : "rx flow"),
+		chan_number(chan));
+
+	if (chan->direction == DMA_MEM_TO_DEV) {
+		seq_printf(s, "einfo - %d, pswords - %d, priority - %d\n",
+			chan->cfg.u.tx.filt_einfo,
+			chan->cfg.u.tx.filt_pswords,
+			chan->cfg.u.tx.priority);
+	} else {
+		seq_printf(s, "einfo - %d, psinfo - %d, desc_type - %d\n",
+			chan->cfg.u.rx.einfo_present,
+			chan->cfg.u.rx.psinfo_present,
+			chan->cfg.u.rx.desc_type);
+		seq_printf(s, "\t\t\tdst_q: [%d], thresh: %d fdq: ",
+			chan->cfg.u.rx.dst_q,
+			chan->cfg.u.rx.thresh);
+		for (i = 0; i < KNAV_DMA_FDQ_PER_CHAN; i++)
+			seq_printf(s, "[%d]", chan->cfg.u.rx.fdq[i]);
+		seq_printf(s, "\n");
+	}
+}
+
+static void dma_debug_show_devices(struct seq_file *s,
+					struct knav_dma_device *dma)
+{
+	struct knav_dma_chan *chan;
+
+	list_for_each_entry(chan, &dma->chan_list, list) {
+		if (atomic_read(&chan->ref_count))
+			dma_debug_show_channels(s, chan);
+	}
+}
+
+static int dma_debug_show(struct seq_file *s, void *v)
+{
+	struct knav_dma_device *dma;
+
+	list_for_each_entry(dma, &kdev->list, list) {
+		if (atomic_read(&dma->ref_count)) {
+			seq_printf(s, "%s : max_tx_chan: (%d), max_rx_flows: (%d)\n",
+			dma->name, dma->max_tx_chan, dma->max_rx_flow);
+			dma_debug_show_devices(s, dma);
+		}
+	}
+
+	return 0;
+}
+
+static int knav_dma_debug_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, dma_debug_show, NULL);
+}
+
+static const struct file_operations knav_dma_debug_ops = {
+	.open		= knav_dma_debug_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static int of_channel_match_helper(struct device_node *np, const char *name,
+					const char **dma_instance)
+{
+	struct of_phandle_args args;
+	struct device_node *dma_node;
+	int index;
+
+	dma_node = of_parse_phandle(np, "ti,navigator-dmas", 0);
+	if (!dma_node)
+		return -ENODEV;
+
+	*dma_instance = dma_node->name;
+	index = of_property_match_string(np, "ti,navigator-dma-names", name);
+	if (index < 0) {
+		dev_err(kdev->dev, "No 'ti,navigator-dma-names' propery\n");
+		return -ENODEV;
+	}
+
+	if (of_parse_phandle_with_fixed_args(np, "ti,navigator-dmas",
+					1, index, &args)) {
+		dev_err(kdev->dev, "Missing the pahndle args name %s\n", name);
+		return -ENODEV;
+	}
+
+	if (args.args[0] < 0) {
+		dev_err(kdev->dev, "Missing args for %s\n", name);
+		return -ENODEV;
+	}
+
+	return args.args[0];
+}
+
+/**
+ * knav_dma_open_channel() - try to setup an exclusive slave channel
+ * @dev:	pointer to client device structure
+ * @name:	slave channel name
+ * @config:	dma configuration parameters
+ *
+ * Returns pointer to appropriate DMA channel on success or NULL.
+ */
+void *knav_dma_open_channel(struct device *dev, const char *name,
+					struct knav_dma_cfg *config)
+{
+	struct knav_dma_chan *chan;
+	struct knav_dma_device *dma;
+	bool found = false;
+	int chan_num = -1;
+	const char *instance;
+
+	if (!kdev) {
+		pr_err("keystone-navigator-dma driver not registered\n");
+		return (void *)-EINVAL;
+	}
+
+	chan_num = of_channel_match_helper(dev->of_node, name, &instance);
+	if (chan_num < 0) {
+		dev_err(kdev->dev, "No DMA instace with name %s\n", name);
+		return (void *)-EINVAL;
+	}
+
+	dev_dbg(kdev->dev, "initializing %s channel %d from DMA %s\n",
+		  config->direction == DMA_MEM_TO_DEV   ? "transmit" :
+		  config->direction == DMA_DEV_TO_MEM ? "receive"  :
+		  "unknown", chan_num, instance);
+
+	if (config->direction != DMA_MEM_TO_DEV &&
+	    config->direction != DMA_DEV_TO_MEM) {
+		dev_err(kdev->dev, "bad direction\n");
+		return (void *)-EINVAL;
+	}
+
+	/* Look for correct dma instance */
+	list_for_each_entry(dma, &kdev->list, list) {
+		if (!strcmp(dma->name, instance)) {
+			found = true;
+			break;
+		}
+	}
+	if (!found) {
+		dev_err(kdev->dev, "No DMA instace with name %s\n", instance);
+		return (void *)-EINVAL;
+	}
+
+	/* Look for correct dma channel from dma instance */
+	found = false;
+	list_for_each_entry(chan, &dma->chan_list, list) {
+		if (config->direction == DMA_MEM_TO_DEV) {
+			if (chan->channel == chan_num) {
+				found = true;
+				break;
+			}
+		} else {
+			if (chan->flow == chan_num) {
+				found = true;
+				break;
+			}
+		}
+	}
+	if (!found) {
+		dev_err(kdev->dev, "channel %d is not in DMA %s\n",
+				chan_num, instance);
+		return (void *)-EINVAL;
+	}
+
+	if (atomic_read(&chan->ref_count) >= 1) {
+		if (!check_config(chan, config)) {
+			dev_err(kdev->dev, "channel %d config miss-match\n",
+				chan_num);
+			return (void *)-EINVAL;
+		}
+	}
+
+	if (atomic_inc_return(&chan->dma->ref_count) <= 1)
+		knav_dma_hw_init(chan->dma);
+
+	if (atomic_inc_return(&chan->ref_count) <= 1)
+		chan_start(chan, config);
+
+	dev_dbg(kdev->dev, "channel %d opened from DMA %s\n",
+				chan_num, instance);
+
+	return chan;
+}
+EXPORT_SYMBOL_GPL(knav_dma_open_channel);
+
+/**
+ * knav_dma_close_channel()	- Destroy a dma channel
+ *
+ * channel:	dma channel handle
+ *
+ */
+void knav_dma_close_channel(void *channel)
+{
+	struct knav_dma_chan *chan = channel;
+
+	if (!kdev) {
+		pr_err("keystone-navigator-dma driver not registered\n");
+		return;
+	}
+
+	if (atomic_dec_return(&chan->ref_count) <= 0)
+		chan_stop(chan);
+
+	if (atomic_dec_return(&chan->dma->ref_count) <= 0)
+		knav_dma_hw_destroy(chan->dma);
+
+	dev_dbg(kdev->dev, "channel %d or flow %d closed from DMA %s\n",
+			chan->channel, chan->flow, chan->dma->name);
+}
+EXPORT_SYMBOL_GPL(knav_dma_close_channel);
+
+static void __iomem *pktdma_get_regs(struct knav_dma_device *dma,
+				struct device_node *node,
+				unsigned index, resource_size_t *_size)
+{
+	struct device *dev = kdev->dev;
+	struct resource res;
+	void __iomem *regs;
+	int ret;
+
+	ret = of_address_to_resource(node, index, &res);
+	if (ret) {
+		dev_err(dev, "Can't translate of node(%s) address for index(%d)\n",
+			node->name, index);
+		return ERR_PTR(ret);
+	}
+
+	regs = devm_ioremap_resource(kdev->dev, &res);
+	if (IS_ERR(regs))
+		dev_err(dev, "Failed to map register base for index(%d) node(%s)\n",
+			index, node->name);
+	if (_size)
+		*_size = resource_size(&res);
+
+	return regs;
+}
+
+static int pktdma_init_rx_chan(struct knav_dma_chan *chan, u32 flow)
+{
+	struct knav_dma_device *dma = chan->dma;
+
+	chan->flow = flow;
+	chan->reg_rx_flow = dma->reg_rx_flow + flow;
+	chan->channel = DMA_INVALID_ID;
+	dev_dbg(kdev->dev, "rx flow(%d) (%p)\n", chan->flow, chan->reg_rx_flow);
+
+	return 0;
+}
+
+static int pktdma_init_tx_chan(struct knav_dma_chan *chan, u32 channel)
+{
+	struct knav_dma_device *dma = chan->dma;
+
+	chan->channel = channel;
+	chan->reg_chan = dma->reg_tx_chan + channel;
+	chan->reg_tx_sched = dma->reg_tx_sched + channel;
+	chan->flow = DMA_INVALID_ID;
+	dev_dbg(kdev->dev, "tx channel(%d) (%p)\n", chan->channel, chan->reg_chan);
+
+	return 0;
+}
+
+static int pktdma_init_chan(struct knav_dma_device *dma,
+				enum dma_transfer_direction dir,
+				unsigned chan_num)
+{
+	struct device *dev = kdev->dev;
+	struct knav_dma_chan *chan;
+	int ret = -EINVAL;
+
+	chan = devm_kzalloc(dev, sizeof(*chan), GFP_KERNEL);
+	if (!chan)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&chan->list);
+	chan->dma	= dma;
+	chan->direction	= DMA_NONE;
+	atomic_set(&chan->ref_count, 0);
+	spin_lock_init(&chan->lock);
+
+	if (dir == DMA_MEM_TO_DEV) {
+		chan->direction = dir;
+		ret = pktdma_init_tx_chan(chan, chan_num);
+	} else if (dir == DMA_DEV_TO_MEM) {
+		chan->direction = dir;
+		ret = pktdma_init_rx_chan(chan, chan_num);
+	} else {
+		dev_err(dev, "channel(%d) direction unknown\n", chan_num);
+	}
+
+	list_add_tail(&chan->list, &dma->chan_list);
+
+	return ret;
+}
+
+static int dma_init(struct device_node *cloud, struct device_node *dma_node)
+{
+	unsigned max_tx_chan, max_rx_chan, max_rx_flow, max_tx_sched;
+	struct device_node *node = dma_node;
+	struct knav_dma_device *dma;
+	int ret, len, num_chan = 0;
+	resource_size_t size;
+	u32 timeout;
+	u32 i;
+
+	dma = devm_kzalloc(kdev->dev, sizeof(*dma), GFP_KERNEL);
+	if (!dma) {
+		dev_err(kdev->dev, "could not allocate driver mem\n");
+		return -ENOMEM;
+	}
+	INIT_LIST_HEAD(&dma->list);
+	INIT_LIST_HEAD(&dma->chan_list);
+
+	if (!of_find_property(cloud, "ti,navigator-cloud-address", &len)) {
+		dev_err(kdev->dev, "unspecified navigator cloud addresses\n");
+		return -ENODEV;
+	}
+
+	dma->logical_queue_managers = len / sizeof(u32);
+	if (dma->logical_queue_managers > DMA_MAX_QMS) {
+		dev_warn(kdev->dev, "too many queue mgrs(>%d) rest ignored\n",
+			 dma->logical_queue_managers);
+		dma->logical_queue_managers = DMA_MAX_QMS;
+	}
+
+	ret = of_property_read_u32_array(cloud, "ti,navigator-cloud-address",
+					dma->qm_base_address,
+					dma->logical_queue_managers);
+	if (ret) {
+		dev_err(kdev->dev, "invalid navigator cloud addresses\n");
+		return -ENODEV;
+	}
+
+	dma->reg_global	 = pktdma_get_regs(dma, node, 0, &size);
+	if (!dma->reg_global)
+		return -ENODEV;
+	if (size < sizeof(struct reg_global)) {
+		dev_err(kdev->dev, "bad size %pa for global regs\n", &size);
+		return -ENODEV;
+	}
+
+	dma->reg_tx_chan = pktdma_get_regs(dma, node, 1, &size);
+	if (!dma->reg_tx_chan)
+		return -ENODEV;
+
+	max_tx_chan = size / sizeof(struct reg_chan);
+	dma->reg_rx_chan = pktdma_get_regs(dma, node, 2, &size);
+	if (!dma->reg_rx_chan)
+		return -ENODEV;
+
+	max_rx_chan = size / sizeof(struct reg_chan);
+	dma->reg_tx_sched = pktdma_get_regs(dma, node, 3, &size);
+	if (!dma->reg_tx_sched)
+		return -ENODEV;
+
+	max_tx_sched = size / sizeof(struct reg_tx_sched);
+	dma->reg_rx_flow = pktdma_get_regs(dma, node, 4, &size);
+	if (!dma->reg_rx_flow)
+		return -ENODEV;
+
+	max_rx_flow = size / sizeof(struct reg_rx_flow);
+	dma->rx_priority = DMA_PRIO_DEFAULT;
+	dma->tx_priority = DMA_PRIO_DEFAULT;
+
+	dma->enable_all	= (of_get_property(node, "ti,enable-all", NULL) != NULL);
+	dma->loopback	= (of_get_property(node, "ti,loop-back",  NULL) != NULL);
+
+	ret = of_property_read_u32(node, "ti,rx-retry-timeout", &timeout);
+	if (ret < 0) {
+		dev_dbg(kdev->dev, "unspecified rx timeout using value %d\n",
+			DMA_RX_TIMEOUT_DEFAULT);
+		timeout = DMA_RX_TIMEOUT_DEFAULT;
+	}
+
+	dma->rx_timeout = timeout;
+	dma->max_rx_chan = max_rx_chan;
+	dma->max_rx_flow = max_rx_flow;
+	dma->max_tx_chan = min(max_tx_chan, max_tx_sched);
+	atomic_set(&dma->ref_count, 0);
+	strcpy(dma->name, node->name);
+	spin_lock_init(&dma->lock);
+
+	for (i = 0; i < dma->max_tx_chan; i++) {
+		if (pktdma_init_chan(dma, DMA_MEM_TO_DEV, i) >= 0)
+			num_chan++;
+	}
+
+	for (i = 0; i < dma->max_rx_flow; i++) {
+		if (pktdma_init_chan(dma, DMA_DEV_TO_MEM, i) >= 0)
+			num_chan++;
+	}
+
+	list_add_tail(&dma->list, &kdev->list);
+
+	/*
+	 * For DSP software usecases or userpace transport software, setup all
+	 * the DMA hardware resources.
+	 */
+	if (dma->enable_all) {
+		atomic_inc(&dma->ref_count);
+		knav_dma_hw_init(dma);
+		dma_hw_enable_all(dma);
+	}
+
+	dev_info(kdev->dev, "DMA %s registered %d logical channels, flows %d, tx chans: %d, rx chans: %d%s\n",
+		dma->name, num_chan, dma->max_rx_flow,
+		dma->max_tx_chan, dma->max_rx_chan,
+		dma->loopback ? ", loopback" : "");
+
+	return 0;
+}
+
+static int knav_dma_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *node = pdev->dev.of_node;
+	struct device_node *child;
+	int ret = 0;
+
+	if (!node) {
+		dev_err(&pdev->dev, "could not find device info\n");
+		return -EINVAL;
+	}
+
+	kdev = devm_kzalloc(dev,
+			sizeof(struct knav_dma_pool_device), GFP_KERNEL);
+	if (!kdev) {
+		dev_err(dev, "could not allocate driver mem\n");
+		return -ENOMEM;
+	}
+
+	kdev->dev = dev;
+	INIT_LIST_HEAD(&kdev->list);
+
+	pm_runtime_enable(kdev->dev);
+	ret = pm_runtime_get_sync(kdev->dev);
+	if (ret < 0) {
+		dev_err(kdev->dev, "unable to enable pktdma, err %d\n", ret);
+		return ret;
+	}
+
+	/* Initialise all packet dmas */
+	for_each_child_of_node(node, child) {
+		ret = dma_init(node, child);
+		if (ret) {
+			dev_err(&pdev->dev, "init failed with %d\n", ret);
+			break;
+		}
+	}
+
+	if (list_empty(&kdev->list)) {
+		dev_err(dev, "no valid dma instance\n");
+		return -ENODEV;
+	}
+
+	debugfs_create_file("knav_dma", S_IFREG | S_IRUGO, NULL, NULL,
+			    &knav_dma_debug_ops);
+
+	return ret;
+}
+
+static int knav_dma_remove(struct platform_device *pdev)
+{
+	struct knav_dma_device *dma;
+
+	list_for_each_entry(dma, &kdev->list, list) {
+		if (atomic_dec_return(&dma->ref_count) == 0)
+			knav_dma_hw_destroy(dma);
+	}
+
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+static struct of_device_id of_match[] = {
+	{ .compatible = "ti,keystone-navigator-dma", },
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, of_match);
+
+static struct platform_driver knav_dma_driver = {
+	.probe	= knav_dma_probe,
+	.remove	= knav_dma_remove,
+	.driver = {
+		.name		= "keystone-navigator-dma",
+		.of_match_table	= of_match,
+	},
+};
+module_platform_driver(knav_dma_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("TI Keystone Navigator Packet DMA driver");
+MODULE_AUTHOR("Sandeep Nair <sandeep_n@ti.com>");
+MODULE_AUTHOR("Santosh Shilimkar <santosh.shilimkar@ti.com>");