1 files changed, 938 insertions, 0 deletions

diff --git a/drivers/dma/sh/shdmac.c b/drivers/dma/sh/shdmac.c
new file mode 100644
index 000000000..5aafe548c
--- /dev/null
+++ b/drivers/dma/sh/shdmac.c
@@ -0,0 +1,938 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Renesas SuperH DMA Engine support
+ *
+ * base is drivers/dma/flsdma.c
+ *
+ * Copyright (C) 2011-2012 Guennadi Liakhovetski <g.liakhovetski@gmx.de>
+ * Copyright (C) 2009 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
+ * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved.
+ * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
+ *
+ * - DMA of SuperH does not have Hardware DMA chain mode.
+ * - MAX DMA size is 16MB.
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kdebug.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/rculist.h>
+#include <linux/sh_dma.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include "../dmaengine.h"
+#include "shdma.h"
+
+/* DMA registers */
+#define SAR	0x00	/* Source Address Register */
+#define DAR	0x04	/* Destination Address Register */
+#define TCR	0x08	/* Transfer Count Register */
+#define CHCR	0x0C	/* Channel Control Register */
+#define DMAOR	0x40	/* DMA Operation Register */
+
+#define TEND	0x18 /* USB-DMAC */
+
+#define SH_DMAE_DRV_NAME "sh-dma-engine"
+
+/* Default MEMCPY transfer size = 2^2 = 4 bytes */
+#define LOG2_DEFAULT_XFER_SIZE	2
+#define SH_DMA_SLAVE_NUMBER 256
+#define SH_DMA_TCR_MAX (16 * 1024 * 1024 - 1)
+
+/*
+ * Used for write-side mutual exclusion for the global device list,
+ * read-side synchronization by way of RCU, and per-controller data.
+ */
+static DEFINE_SPINLOCK(sh_dmae_lock);
+static LIST_HEAD(sh_dmae_devices);
+
+/*
+ * Different DMAC implementations provide different ways to clear DMA channels:
+ * (1) none - no CHCLR registers are available
+ * (2) one CHCLR register per channel - 0 has to be written to it to clear
+ *     channel buffers
+ * (3) one CHCLR per several channels - 1 has to be written to the bit,
+ *     corresponding to the specific channel to reset it
+ */
+static void channel_clear(struct sh_dmae_chan *sh_dc)
+{
+	struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
+	const struct sh_dmae_channel *chan_pdata = shdev->pdata->channel +
+		sh_dc->shdma_chan.id;
+	u32 val = shdev->pdata->chclr_bitwise ? 1 << chan_pdata->chclr_bit : 0;
+
+	__raw_writel(val, shdev->chan_reg + chan_pdata->chclr_offset);
+}
+
+static void sh_dmae_writel(struct sh_dmae_chan *sh_dc, u32 data, u32 reg)
+{
+	__raw_writel(data, sh_dc->base + reg);
+}
+
+static u32 sh_dmae_readl(struct sh_dmae_chan *sh_dc, u32 reg)
+{
+	return __raw_readl(sh_dc->base + reg);
+}
+
+static u16 dmaor_read(struct sh_dmae_device *shdev)
+{
+	void __iomem *addr = shdev->chan_reg + DMAOR;
+
+	if (shdev->pdata->dmaor_is_32bit)
+		return __raw_readl(addr);
+	else
+		return __raw_readw(addr);
+}
+
+static void dmaor_write(struct sh_dmae_device *shdev, u16 data)
+{
+	void __iomem *addr = shdev->chan_reg + DMAOR;
+
+	if (shdev->pdata->dmaor_is_32bit)
+		__raw_writel(data, addr);
+	else
+		__raw_writew(data, addr);
+}
+
+static void chcr_write(struct sh_dmae_chan *sh_dc, u32 data)
+{
+	struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
+
+	__raw_writel(data, sh_dc->base + shdev->chcr_offset);
+}
+
+static u32 chcr_read(struct sh_dmae_chan *sh_dc)
+{
+	struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
+
+	return __raw_readl(sh_dc->base + shdev->chcr_offset);
+}
+
+/*
+ * Reset DMA controller
+ *
+ * SH7780 has two DMAOR register
+ */
+static void sh_dmae_ctl_stop(struct sh_dmae_device *shdev)
+{
+	unsigned short dmaor;
+	unsigned long flags;
+
+	spin_lock_irqsave(&sh_dmae_lock, flags);
+
+	dmaor = dmaor_read(shdev);
+	dmaor_write(shdev, dmaor & ~(DMAOR_NMIF | DMAOR_AE | DMAOR_DME));
+
+	spin_unlock_irqrestore(&sh_dmae_lock, flags);
+}
+
+static int sh_dmae_rst(struct sh_dmae_device *shdev)
+{
+	unsigned short dmaor;
+	unsigned long flags;
+
+	spin_lock_irqsave(&sh_dmae_lock, flags);
+
+	dmaor = dmaor_read(shdev) & ~(DMAOR_NMIF | DMAOR_AE | DMAOR_DME);
+
+	if (shdev->pdata->chclr_present) {
+		int i;
+		for (i = 0; i < shdev->pdata->channel_num; i++) {
+			struct sh_dmae_chan *sh_chan = shdev->chan[i];
+			if (sh_chan)
+				channel_clear(sh_chan);
+		}
+	}
+
+	dmaor_write(shdev, dmaor | shdev->pdata->dmaor_init);
+
+	dmaor = dmaor_read(shdev);
+
+	spin_unlock_irqrestore(&sh_dmae_lock, flags);
+
+	if (dmaor & (DMAOR_AE | DMAOR_NMIF)) {
+		dev_warn(shdev->shdma_dev.dma_dev.dev, "Can't initialize DMAOR.\n");
+		return -EIO;
+	}
+	if (shdev->pdata->dmaor_init & ~dmaor)
+		dev_warn(shdev->shdma_dev.dma_dev.dev,
+			 "DMAOR=0x%x hasn't latched the initial value 0x%x.\n",
+			 dmaor, shdev->pdata->dmaor_init);
+	return 0;
+}
+
+static bool dmae_is_busy(struct sh_dmae_chan *sh_chan)
+{
+	u32 chcr = chcr_read(sh_chan);
+
+	if ((chcr & (CHCR_DE | CHCR_TE)) == CHCR_DE)
+		return true; /* working */
+
+	return false; /* waiting */
+}
+
+static unsigned int calc_xmit_shift(struct sh_dmae_chan *sh_chan, u32 chcr)
+{
+	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
+	const struct sh_dmae_pdata *pdata = shdev->pdata;
+	int cnt = ((chcr & pdata->ts_low_mask) >> pdata->ts_low_shift) |
+		((chcr & pdata->ts_high_mask) >> pdata->ts_high_shift);
+
+	if (cnt >= pdata->ts_shift_num)
+		cnt = 0;
+
+	return pdata->ts_shift[cnt];
+}
+
+static u32 log2size_to_chcr(struct sh_dmae_chan *sh_chan, int l2size)
+{
+	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
+	const struct sh_dmae_pdata *pdata = shdev->pdata;
+	int i;
+
+	for (i = 0; i < pdata->ts_shift_num; i++)
+		if (pdata->ts_shift[i] == l2size)
+			break;
+
+	if (i == pdata->ts_shift_num)
+		i = 0;
+
+	return ((i << pdata->ts_low_shift) & pdata->ts_low_mask) |
+		((i << pdata->ts_high_shift) & pdata->ts_high_mask);
+}
+
+static void dmae_set_reg(struct sh_dmae_chan *sh_chan, struct sh_dmae_regs *hw)
+{
+	sh_dmae_writel(sh_chan, hw->sar, SAR);
+	sh_dmae_writel(sh_chan, hw->dar, DAR);
+	sh_dmae_writel(sh_chan, hw->tcr >> sh_chan->xmit_shift, TCR);
+}
+
+static void dmae_start(struct sh_dmae_chan *sh_chan)
+{
+	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
+	u32 chcr = chcr_read(sh_chan);
+
+	if (shdev->pdata->needs_tend_set)
+		sh_dmae_writel(sh_chan, 0xFFFFFFFF, TEND);
+
+	chcr |= CHCR_DE | shdev->chcr_ie_bit;
+	chcr_write(sh_chan, chcr & ~CHCR_TE);
+}
+
+static void dmae_init(struct sh_dmae_chan *sh_chan)
+{
+	/*
+	 * Default configuration for dual address memory-memory transfer.
+	 */
+	u32 chcr = DM_INC | SM_INC | RS_AUTO | log2size_to_chcr(sh_chan,
+						   LOG2_DEFAULT_XFER_SIZE);
+	sh_chan->xmit_shift = calc_xmit_shift(sh_chan, chcr);
+	chcr_write(sh_chan, chcr);
+}
+
+static int dmae_set_chcr(struct sh_dmae_chan *sh_chan, u32 val)
+{
+	/* If DMA is active, cannot set CHCR. TODO: remove this superfluous check */
+	if (dmae_is_busy(sh_chan))
+		return -EBUSY;
+
+	sh_chan->xmit_shift = calc_xmit_shift(sh_chan, val);
+	chcr_write(sh_chan, val);
+
+	return 0;
+}
+
+static int dmae_set_dmars(struct sh_dmae_chan *sh_chan, u16 val)
+{
+	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
+	const struct sh_dmae_pdata *pdata = shdev->pdata;
+	const struct sh_dmae_channel *chan_pdata = &pdata->channel[sh_chan->shdma_chan.id];
+	void __iomem *addr = shdev->dmars;
+	unsigned int shift = chan_pdata->dmars_bit;
+
+	if (dmae_is_busy(sh_chan))
+		return -EBUSY;
+
+	if (pdata->no_dmars)
+		return 0;
+
+	/* in the case of a missing DMARS resource use first memory window */
+	if (!addr)
+		addr = shdev->chan_reg;
+	addr += chan_pdata->dmars;
+
+	__raw_writew((__raw_readw(addr) & (0xff00 >> shift)) | (val << shift),
+		     addr);
+
+	return 0;
+}
+
+static void sh_dmae_start_xfer(struct shdma_chan *schan,
+			       struct shdma_desc *sdesc)
+{
+	struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
+						    shdma_chan);
+	struct sh_dmae_desc *sh_desc = container_of(sdesc,
+					struct sh_dmae_desc, shdma_desc);
+	dev_dbg(sh_chan->shdma_chan.dev, "Queue #%d to %d: %u@%x -> %x\n",
+		sdesc->async_tx.cookie, sh_chan->shdma_chan.id,
+		sh_desc->hw.tcr, sh_desc->hw.sar, sh_desc->hw.dar);
+	/* Get the ld start address from ld_queue */
+	dmae_set_reg(sh_chan, &sh_desc->hw);
+	dmae_start(sh_chan);
+}
+
+static bool sh_dmae_channel_busy(struct shdma_chan *schan)
+{
+	struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
+						    shdma_chan);
+	return dmae_is_busy(sh_chan);
+}
+
+static void sh_dmae_setup_xfer(struct shdma_chan *schan,
+			       int slave_id)
+{
+	struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
+						    shdma_chan);
+
+	if (slave_id >= 0) {
+		const struct sh_dmae_slave_config *cfg =
+			sh_chan->config;
+
+		dmae_set_dmars(sh_chan, cfg->mid_rid);
+		dmae_set_chcr(sh_chan, cfg->chcr);
+	} else {
+		dmae_init(sh_chan);
+	}
+}
+
+/*
+ * Find a slave channel configuration from the contoller list by either a slave
+ * ID in the non-DT case, or by a MID/RID value in the DT case
+ */
+static const struct sh_dmae_slave_config *dmae_find_slave(
+	struct sh_dmae_chan *sh_chan, int match)
+{
+	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
+	const struct sh_dmae_pdata *pdata = shdev->pdata;
+	const struct sh_dmae_slave_config *cfg;
+	int i;
+
+	if (!sh_chan->shdma_chan.dev->of_node) {
+		if (match >= SH_DMA_SLAVE_NUMBER)
+			return NULL;
+
+		for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++)
+			if (cfg->slave_id == match)
+				return cfg;
+	} else {
+		for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++)
+			if (cfg->mid_rid == match) {
+				sh_chan->shdma_chan.slave_id = i;
+				return cfg;
+			}
+	}
+
+	return NULL;
+}
+
+static int sh_dmae_set_slave(struct shdma_chan *schan,
+			     int slave_id, dma_addr_t slave_addr, bool try)
+{
+	struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
+						    shdma_chan);
+	const struct sh_dmae_slave_config *cfg = dmae_find_slave(sh_chan, slave_id);
+	if (!cfg)
+		return -ENXIO;
+
+	if (!try) {
+		sh_chan->config = cfg;
+		sh_chan->slave_addr = slave_addr ? : cfg->addr;
+	}
+
+	return 0;
+}
+
+static void dmae_halt(struct sh_dmae_chan *sh_chan)
+{
+	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
+	u32 chcr = chcr_read(sh_chan);
+
+	chcr &= ~(CHCR_DE | CHCR_TE | shdev->chcr_ie_bit);
+	chcr_write(sh_chan, chcr);
+}
+
+static int sh_dmae_desc_setup(struct shdma_chan *schan,
+			      struct shdma_desc *sdesc,
+			      dma_addr_t src, dma_addr_t dst, size_t *len)
+{
+	struct sh_dmae_desc *sh_desc = container_of(sdesc,
+					struct sh_dmae_desc, shdma_desc);
+
+	if (*len > schan->max_xfer_len)
+		*len = schan->max_xfer_len;
+
+	sh_desc->hw.sar = src;
+	sh_desc->hw.dar = dst;
+	sh_desc->hw.tcr = *len;
+
+	return 0;
+}
+
+static void sh_dmae_halt(struct shdma_chan *schan)
+{
+	struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
+						    shdma_chan);
+	dmae_halt(sh_chan);
+}
+
+static bool sh_dmae_chan_irq(struct shdma_chan *schan, int irq)
+{
+	struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
+						    shdma_chan);
+
+	if (!(chcr_read(sh_chan) & CHCR_TE))
+		return false;
+
+	/* DMA stop */
+	dmae_halt(sh_chan);
+
+	return true;
+}
+
+static size_t sh_dmae_get_partial(struct shdma_chan *schan,
+				  struct shdma_desc *sdesc)
+{
+	struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
+						    shdma_chan);
+	struct sh_dmae_desc *sh_desc = container_of(sdesc,
+					struct sh_dmae_desc, shdma_desc);
+	return sh_desc->hw.tcr -
+		(sh_dmae_readl(sh_chan, TCR) << sh_chan->xmit_shift);
+}
+
+/* Called from error IRQ or NMI */
+static bool sh_dmae_reset(struct sh_dmae_device *shdev)
+{
+	bool ret;
+
+	/* halt the dma controller */
+	sh_dmae_ctl_stop(shdev);
+
+	/* We cannot detect, which channel caused the error, have to reset all */
+	ret = shdma_reset(&shdev->shdma_dev);
+
+	sh_dmae_rst(shdev);
+
+	return ret;
+}
+
+static irqreturn_t sh_dmae_err(int irq, void *data)
+{
+	struct sh_dmae_device *shdev = data;
+
+	if (!(dmaor_read(shdev) & DMAOR_AE))
+		return IRQ_NONE;
+
+	sh_dmae_reset(shdev);
+	return IRQ_HANDLED;
+}
+
+static bool sh_dmae_desc_completed(struct shdma_chan *schan,
+				   struct shdma_desc *sdesc)
+{
+	struct sh_dmae_chan *sh_chan = container_of(schan,
+					struct sh_dmae_chan, shdma_chan);
+	struct sh_dmae_desc *sh_desc = container_of(sdesc,
+					struct sh_dmae_desc, shdma_desc);
+	u32 sar_buf = sh_dmae_readl(sh_chan, SAR);
+	u32 dar_buf = sh_dmae_readl(sh_chan, DAR);
+
+	return	(sdesc->direction == DMA_DEV_TO_MEM &&
+		 (sh_desc->hw.dar + sh_desc->hw.tcr) == dar_buf) ||
+		(sdesc->direction != DMA_DEV_TO_MEM &&
+		 (sh_desc->hw.sar + sh_desc->hw.tcr) == sar_buf);
+}
+
+static bool sh_dmae_nmi_notify(struct sh_dmae_device *shdev)
+{
+	/* Fast path out if NMIF is not asserted for this controller */
+	if ((dmaor_read(shdev) & DMAOR_NMIF) == 0)
+		return false;
+
+	return sh_dmae_reset(shdev);
+}
+
+static int sh_dmae_nmi_handler(struct notifier_block *self,
+			       unsigned long cmd, void *data)
+{
+	struct sh_dmae_device *shdev;
+	int ret = NOTIFY_DONE;
+	bool triggered;
+
+	/*
+	 * Only concern ourselves with NMI events.
+	 *
+	 * Normally we would check the die chain value, but as this needs
+	 * to be architecture independent, check for NMI context instead.
+	 */
+	if (!in_nmi())
+		return NOTIFY_DONE;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(shdev, &sh_dmae_devices, node) {
+		/*
+		 * Only stop if one of the controllers has NMIF asserted,
+		 * we do not want to interfere with regular address error
+		 * handling or NMI events that don't concern the DMACs.
+		 */
+		triggered = sh_dmae_nmi_notify(shdev);
+		if (triggered == true)
+			ret = NOTIFY_OK;
+	}
+	rcu_read_unlock();
+
+	return ret;
+}
+
+static struct notifier_block sh_dmae_nmi_notifier __read_mostly = {
+	.notifier_call	= sh_dmae_nmi_handler,
+
+	/* Run before NMI debug handler and KGDB */
+	.priority	= 1,
+};
+
+static int sh_dmae_chan_probe(struct sh_dmae_device *shdev, int id,
+					int irq, unsigned long flags)
+{
+	const struct sh_dmae_channel *chan_pdata = &shdev->pdata->channel[id];
+	struct shdma_dev *sdev = &shdev->shdma_dev;
+	struct platform_device *pdev = to_platform_device(sdev->dma_dev.dev);
+	struct sh_dmae_chan *sh_chan;
+	struct shdma_chan *schan;
+	int err;
+
+	sh_chan = devm_kzalloc(sdev->dma_dev.dev, sizeof(struct sh_dmae_chan),
+			       GFP_KERNEL);
+	if (!sh_chan)
+		return -ENOMEM;
+
+	schan = &sh_chan->shdma_chan;
+	schan->max_xfer_len = SH_DMA_TCR_MAX + 1;
+
+	shdma_chan_probe(sdev, schan, id);
+
+	sh_chan->base = shdev->chan_reg + chan_pdata->offset;
+
+	/* set up channel irq */
+	if (pdev->id >= 0)
+		snprintf(sh_chan->dev_id, sizeof(sh_chan->dev_id),
+			 "sh-dmae%d.%d", pdev->id, id);
+	else
+		snprintf(sh_chan->dev_id, sizeof(sh_chan->dev_id),
+			 "sh-dma%d", id);
+
+	err = shdma_request_irq(schan, irq, flags, sh_chan->dev_id);
+	if (err) {
+		dev_err(sdev->dma_dev.dev,
+			"DMA channel %d request_irq error %d\n",
+			id, err);
+		goto err_no_irq;
+	}
+
+	shdev->chan[id] = sh_chan;
+	return 0;
+
+err_no_irq:
+	/* remove from dmaengine device node */
+	shdma_chan_remove(schan);
+	return err;
+}
+
+static void sh_dmae_chan_remove(struct sh_dmae_device *shdev)
+{
+	struct shdma_chan *schan;
+	int i;
+
+	shdma_for_each_chan(schan, &shdev->shdma_dev, i) {
+		BUG_ON(!schan);
+
+		shdma_chan_remove(schan);
+	}
+}
+
+#ifdef CONFIG_PM
+static int sh_dmae_runtime_suspend(struct device *dev)
+{
+	struct sh_dmae_device *shdev = dev_get_drvdata(dev);
+
+	sh_dmae_ctl_stop(shdev);
+	return 0;
+}
+
+static int sh_dmae_runtime_resume(struct device *dev)
+{
+	struct sh_dmae_device *shdev = dev_get_drvdata(dev);
+
+	return sh_dmae_rst(shdev);
+}
+#endif
+
+#ifdef CONFIG_PM_SLEEP
+static int sh_dmae_suspend(struct device *dev)
+{
+	struct sh_dmae_device *shdev = dev_get_drvdata(dev);
+
+	sh_dmae_ctl_stop(shdev);
+	return 0;
+}
+
+static int sh_dmae_resume(struct device *dev)
+{
+	struct sh_dmae_device *shdev = dev_get_drvdata(dev);
+	int i, ret;
+
+	ret = sh_dmae_rst(shdev);
+	if (ret < 0)
+		dev_err(dev, "Failed to reset!\n");
+
+	for (i = 0; i < shdev->pdata->channel_num; i++) {
+		struct sh_dmae_chan *sh_chan = shdev->chan[i];
+
+		if (!sh_chan->shdma_chan.desc_num)
+			continue;
+
+		if (sh_chan->shdma_chan.slave_id >= 0) {
+			const struct sh_dmae_slave_config *cfg = sh_chan->config;
+			dmae_set_dmars(sh_chan, cfg->mid_rid);
+			dmae_set_chcr(sh_chan, cfg->chcr);
+		} else {
+			dmae_init(sh_chan);
+		}
+	}
+
+	return 0;
+}
+#endif
+
+static const struct dev_pm_ops sh_dmae_pm = {
+	SET_SYSTEM_SLEEP_PM_OPS(sh_dmae_suspend, sh_dmae_resume)
+	SET_RUNTIME_PM_OPS(sh_dmae_runtime_suspend, sh_dmae_runtime_resume,
+			   NULL)
+};
+
+static dma_addr_t sh_dmae_slave_addr(struct shdma_chan *schan)
+{
+	struct sh_dmae_chan *sh_chan = container_of(schan,
+					struct sh_dmae_chan, shdma_chan);
+
+	/*
+	 * Implicit BUG_ON(!sh_chan->config)
+	 * This is an exclusive slave DMA operation, may only be called after a
+	 * successful slave configuration.
+	 */
+	return sh_chan->slave_addr;
+}
+
+static struct shdma_desc *sh_dmae_embedded_desc(void *buf, int i)
+{
+	return &((struct sh_dmae_desc *)buf)[i].shdma_desc;
+}
+
+static const struct shdma_ops sh_dmae_shdma_ops = {
+	.desc_completed = sh_dmae_desc_completed,
+	.halt_channel = sh_dmae_halt,
+	.channel_busy = sh_dmae_channel_busy,
+	.slave_addr = sh_dmae_slave_addr,
+	.desc_setup = sh_dmae_desc_setup,
+	.set_slave = sh_dmae_set_slave,
+	.setup_xfer = sh_dmae_setup_xfer,
+	.start_xfer = sh_dmae_start_xfer,
+	.embedded_desc = sh_dmae_embedded_desc,
+	.chan_irq = sh_dmae_chan_irq,
+	.get_partial = sh_dmae_get_partial,
+};
+
+static int sh_dmae_probe(struct platform_device *pdev)
+{
+	const enum dma_slave_buswidth widths =
+		DMA_SLAVE_BUSWIDTH_1_BYTE   | DMA_SLAVE_BUSWIDTH_2_BYTES |
+		DMA_SLAVE_BUSWIDTH_4_BYTES  | DMA_SLAVE_BUSWIDTH_8_BYTES |
+		DMA_SLAVE_BUSWIDTH_16_BYTES | DMA_SLAVE_BUSWIDTH_32_BYTES;
+	const struct sh_dmae_pdata *pdata;
+	unsigned long chan_flag[SH_DMAE_MAX_CHANNELS] = {};
+	int chan_irq[SH_DMAE_MAX_CHANNELS];
+	unsigned long irqflags = 0;
+	int err, errirq, i, irq_cnt = 0, irqres = 0, irq_cap = 0;
+	struct sh_dmae_device *shdev;
+	struct dma_device *dma_dev;
+	struct resource *chan, *dmars, *errirq_res, *chanirq_res;
+
+	if (pdev->dev.of_node)
+		pdata = of_device_get_match_data(&pdev->dev);
+	else
+		pdata = dev_get_platdata(&pdev->dev);
+
+	/* get platform data */
+	if (!pdata || !pdata->channel_num)
+		return -ENODEV;
+
+	chan = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	/* DMARS area is optional */
+	dmars = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	/*
+	 * IRQ resources:
+	 * 1. there always must be at least one IRQ IO-resource. On SH4 it is
+	 *    the error IRQ, in which case it is the only IRQ in this resource:
+	 *    start == end. If it is the only IRQ resource, all channels also
+	 *    use the same IRQ.
+	 * 2. DMA channel IRQ resources can be specified one per resource or in
+	 *    ranges (start != end)
+	 * 3. iff all events (channels and, optionally, error) on this
+	 *    controller use the same IRQ, only one IRQ resource can be
+	 *    specified, otherwise there must be one IRQ per channel, even if
+	 *    some of them are equal
+	 * 4. if all IRQs on this controller are equal or if some specific IRQs
+	 *    specify IORESOURCE_IRQ_SHAREABLE in their resources, they will be
+	 *    requested with the IRQF_SHARED flag
+	 */
+	errirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!chan || !errirq_res)
+		return -ENODEV;
+
+	shdev = devm_kzalloc(&pdev->dev, sizeof(struct sh_dmae_device),
+			     GFP_KERNEL);
+	if (!shdev)
+		return -ENOMEM;
+
+	dma_dev = &shdev->shdma_dev.dma_dev;
+
+	shdev->chan_reg = devm_ioremap_resource(&pdev->dev, chan);
+	if (IS_ERR(shdev->chan_reg))
+		return PTR_ERR(shdev->chan_reg);
+	if (dmars) {
+		shdev->dmars = devm_ioremap_resource(&pdev->dev, dmars);
+		if (IS_ERR(shdev->dmars))
+			return PTR_ERR(shdev->dmars);
+	}
+
+	dma_dev->src_addr_widths = widths;
+	dma_dev->dst_addr_widths = widths;
+	dma_dev->directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
+	dma_dev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
+
+	if (!pdata->slave_only)
+		dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
+	if (pdata->slave && pdata->slave_num)
+		dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);
+
+	/* Default transfer size of 32 bytes requires 32-byte alignment */
+	dma_dev->copy_align = LOG2_DEFAULT_XFER_SIZE;
+
+	shdev->shdma_dev.ops = &sh_dmae_shdma_ops;
+	shdev->shdma_dev.desc_size = sizeof(struct sh_dmae_desc);
+	err = shdma_init(&pdev->dev, &shdev->shdma_dev,
+			      pdata->channel_num);
+	if (err < 0)
+		goto eshdma;
+
+	/* platform data */
+	shdev->pdata = pdata;
+
+	if (pdata->chcr_offset)
+		shdev->chcr_offset = pdata->chcr_offset;
+	else
+		shdev->chcr_offset = CHCR;
+
+	if (pdata->chcr_ie_bit)
+		shdev->chcr_ie_bit = pdata->chcr_ie_bit;
+	else
+		shdev->chcr_ie_bit = CHCR_IE;
+
+	platform_set_drvdata(pdev, shdev);
+
+	pm_runtime_enable(&pdev->dev);
+	err = pm_runtime_get_sync(&pdev->dev);
+	if (err < 0)
+		dev_err(&pdev->dev, "%s(): GET = %d\n", __func__, err);
+
+	spin_lock_irq(&sh_dmae_lock);
+	list_add_tail_rcu(&shdev->node, &sh_dmae_devices);
+	spin_unlock_irq(&sh_dmae_lock);
+
+	/* reset dma controller - only needed as a test */
+	err = sh_dmae_rst(shdev);
+	if (err)
+		goto rst_err;
+
+	if (IS_ENABLED(CONFIG_CPU_SH4) || IS_ENABLED(CONFIG_ARCH_RENESAS)) {
+		chanirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
+
+		if (!chanirq_res)
+			chanirq_res = errirq_res;
+		else
+			irqres++;
+
+		if (chanirq_res == errirq_res ||
+		    (errirq_res->flags & IORESOURCE_BITS) == IORESOURCE_IRQ_SHAREABLE)
+			irqflags = IRQF_SHARED;
+
+		errirq = errirq_res->start;
+
+		err = devm_request_irq(&pdev->dev, errirq, sh_dmae_err,
+				       irqflags, "DMAC Address Error", shdev);
+		if (err) {
+			dev_err(&pdev->dev,
+				"DMA failed requesting irq #%d, error %d\n",
+				errirq, err);
+			goto eirq_err;
+		}
+	} else {
+		chanirq_res = errirq_res;
+	}
+
+	if (chanirq_res->start == chanirq_res->end &&
+	    !platform_get_resource(pdev, IORESOURCE_IRQ, 1)) {
+		/* Special case - all multiplexed */
+		for (; irq_cnt < pdata->channel_num; irq_cnt++) {
+			if (irq_cnt < SH_DMAE_MAX_CHANNELS) {
+				chan_irq[irq_cnt] = chanirq_res->start;
+				chan_flag[irq_cnt] = IRQF_SHARED;
+			} else {
+				irq_cap = 1;
+				break;
+			}
+		}
+	} else {
+		do {
+			for (i = chanirq_res->start; i <= chanirq_res->end; i++) {
+				if (irq_cnt >= SH_DMAE_MAX_CHANNELS) {
+					irq_cap = 1;
+					break;
+				}
+
+				if ((errirq_res->flags & IORESOURCE_BITS) ==
+				    IORESOURCE_IRQ_SHAREABLE)
+					chan_flag[irq_cnt] = IRQF_SHARED;
+				else
+					chan_flag[irq_cnt] = 0;
+				dev_dbg(&pdev->dev,
+					"Found IRQ %d for channel %d\n",
+					i, irq_cnt);
+				chan_irq[irq_cnt++] = i;
+			}
+
+			if (irq_cnt >= SH_DMAE_MAX_CHANNELS)
+				break;
+
+			chanirq_res = platform_get_resource(pdev,
+						IORESOURCE_IRQ, ++irqres);
+		} while (irq_cnt < pdata->channel_num && chanirq_res);
+	}
+
+	/* Create DMA Channel */
+	for (i = 0; i < irq_cnt; i++) {
+		err = sh_dmae_chan_probe(shdev, i, chan_irq[i], chan_flag[i]);
+		if (err)
+			goto chan_probe_err;
+	}
+
+	if (irq_cap)
+		dev_notice(&pdev->dev, "Attempting to register %d DMA "
+			   "channels when a maximum of %d are supported.\n",
+			   pdata->channel_num, SH_DMAE_MAX_CHANNELS);
+
+	pm_runtime_put(&pdev->dev);
+
+	err = dma_async_device_register(&shdev->shdma_dev.dma_dev);
+	if (err < 0)
+		goto edmadevreg;
+
+	return err;
+
+edmadevreg:
+	pm_runtime_get(&pdev->dev);
+
+chan_probe_err:
+	sh_dmae_chan_remove(shdev);
+
+eirq_err:
+rst_err:
+	spin_lock_irq(&sh_dmae_lock);
+	list_del_rcu(&shdev->node);
+	spin_unlock_irq(&sh_dmae_lock);
+
+	pm_runtime_put(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+
+	shdma_cleanup(&shdev->shdma_dev);
+eshdma:
+	synchronize_rcu();
+
+	return err;
+}
+
+static int sh_dmae_remove(struct platform_device *pdev)
+{
+	struct sh_dmae_device *shdev = platform_get_drvdata(pdev);
+	struct dma_device *dma_dev = &shdev->shdma_dev.dma_dev;
+
+	dma_async_device_unregister(dma_dev);
+
+	spin_lock_irq(&sh_dmae_lock);
+	list_del_rcu(&shdev->node);
+	spin_unlock_irq(&sh_dmae_lock);
+
+	pm_runtime_disable(&pdev->dev);
+
+	sh_dmae_chan_remove(shdev);
+	shdma_cleanup(&shdev->shdma_dev);
+
+	synchronize_rcu();
+
+	return 0;
+}
+
+static struct platform_driver sh_dmae_driver = {
+	.driver		= {
+		.pm	= &sh_dmae_pm,
+		.name	= SH_DMAE_DRV_NAME,
+	},
+	.remove		= sh_dmae_remove,
+};
+
+static int __init sh_dmae_init(void)
+{
+	/* Wire up NMI handling */
+	int err = register_die_notifier(&sh_dmae_nmi_notifier);
+	if (err)
+		return err;
+
+	return platform_driver_probe(&sh_dmae_driver, sh_dmae_probe);
+}
+module_init(sh_dmae_init);
+
+static void __exit sh_dmae_exit(void)
+{
+	platform_driver_unregister(&sh_dmae_driver);
+
+	unregister_die_notifier(&sh_dmae_nmi_notifier);
+}
+module_exit(sh_dmae_exit);
+
+MODULE_AUTHOR("Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>");
+MODULE_DESCRIPTION("Renesas SH DMA Engine driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" SH_DMAE_DRV_NAME);