[v1,3/5] dmaengine: dw: Split DW and iDMA 32-bit operations

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Fri, Nov 30, 2018 at 10:36:44PM +0200, Andy Shevchenko wrote:
> Here is a kinda big refactoring that should have been done
> in the first place, when Intel iDMA 32-bit support appeared.
> 
> It splits operations which are different to Synopsys DesignWare and
> Intel iDMA 32-bit controllers.
> 
> No functional change intended.

While first two are real bug fixes and really small, this one bigger and
suddenly has a typo which I didn't notice during my tests.

Vinod, please, consider applying first two until I will come with better this
one and might be something more.

> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>  drivers/dma/dw/Makefile              |   2 +-
>  drivers/dma/dw/core.c                | 188 +++++----------------------
>  drivers/dma/dw/dw.c                  | 109 ++++++++++++++++
>  drivers/dma/dw/idma32.c              | 137 +++++++++++++++++++
>  drivers/dma/dw/internal.h            |  10 +-
>  drivers/dma/dw/pci.c                 |  45 ++++---
>  drivers/dma/dw/platform.c            |   8 +-
>  drivers/dma/dw/regs.h                |  13 ++
>  include/linux/dma/dw.h               |   4 +
>  include/linux/platform_data/dma-dw.h |   2 -
>  10 files changed, 339 insertions(+), 179 deletions(-)
>  create mode 100644 drivers/dma/dw/dw.c
>  create mode 100644 drivers/dma/dw/idma32.c
> 
> diff --git a/drivers/dma/dw/Makefile b/drivers/dma/dw/Makefile
> index 2b949c2e4504..63ed895c09aa 100644
> --- a/drivers/dma/dw/Makefile
> +++ b/drivers/dma/dw/Makefile
> @@ -1,6 +1,6 @@
>  # SPDX-License-Identifier: GPL-2.0
>  obj-$(CONFIG_DW_DMAC_CORE)	+= dw_dmac_core.o
> -dw_dmac_core-objs	:= core.o
> +dw_dmac_core-objs	:= core.o dw.o idma32.o
>  
>  obj-$(CONFIG_DW_DMAC)		+= dw_dmac.o
>  dw_dmac-objs		:= platform.o
> diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
> index e85b078fc207..711f4d19bbf1 100644
> --- a/drivers/dma/dw/core.c
> +++ b/drivers/dma/dw/core.c
> @@ -138,42 +138,6 @@ static void dwc_desc_put(struct dw_dma_chan *dwc, struct dw_desc *desc)
>  	dwc->descs_allocated--;
>  }
>  
> -static void dwc_initialize_chan_idma32(struct dw_dma_chan *dwc)
> -{
> -	u32 cfghi = 0;
> -	u32 cfglo = 0;
> -
> -	/* Set default burst alignment */
> -	cfglo |= IDMA32C_CFGL_DST_BURST_ALIGN | IDMA32C_CFGL_SRC_BURST_ALIGN;
> -
> -	/* Low 4 bits of the request lines */
> -	cfghi |= IDMA32C_CFGH_DST_PER(dwc->dws.dst_id & 0xf);
> -	cfghi |= IDMA32C_CFGH_SRC_PER(dwc->dws.src_id & 0xf);
> -
> -	/* Request line extension (2 bits) */
> -	cfghi |= IDMA32C_CFGH_DST_PER_EXT(dwc->dws.dst_id >> 4 & 0x3);
> -	cfghi |= IDMA32C_CFGH_SRC_PER_EXT(dwc->dws.src_id >> 4 & 0x3);
> -
> -	channel_writel(dwc, CFG_LO, cfglo);
> -	channel_writel(dwc, CFG_HI, cfghi);
> -}
> -
> -static void dwc_initialize_chan_dw(struct dw_dma_chan *dwc)
> -{
> -	u32 cfghi = DWC_CFGH_FIFO_MODE;
> -	u32 cfglo = DWC_CFGL_CH_PRIOR(dwc->priority);
> -	bool hs_polarity = dwc->dws.hs_polarity;
> -
> -	cfghi |= DWC_CFGH_DST_PER(dwc->dws.dst_id);
> -	cfghi |= DWC_CFGH_SRC_PER(dwc->dws.src_id);
> -
> -	/* Set polarity of handshake interface */
> -	cfglo |= hs_polarity ? DWC_CFGL_HS_DST_POL | DWC_CFGL_HS_SRC_POL : 0;
> -
> -	channel_writel(dwc, CFG_LO, cfglo);
> -	channel_writel(dwc, CFG_HI, cfghi);
> -}
> -
>  static void dwc_initialize(struct dw_dma_chan *dwc)
>  {
>  	struct dw_dma *dw = to_dw_dma(dwc->chan.device);
> @@ -181,10 +145,7 @@ static void dwc_initialize(struct dw_dma_chan *dwc)
>  	if (test_bit(DW_DMA_IS_INITIALIZED, &dwc->flags))
>  		return;
>  
> -	if (dw->pdata->is_idma32)
> -		dwc_initialize_chan_idma32(dwc);
> -	else
> -		dwc_initialize_chan_dw(dwc);
> +	dw->initialize_chan(dwc);
>  
>  	/* Enable interrupts */
>  	channel_set_bit(dw, MASK.XFER, dwc->mask);
> @@ -213,37 +174,6 @@ static inline void dwc_chan_disable(struct dw_dma *dw, struct dw_dma_chan *dwc)
>  		cpu_relax();
>  }
>  
> -static u32 bytes2block(struct dw_dma_chan *dwc, size_t bytes,
> -			  unsigned int width, size_t *len)
> -{
> -	struct dw_dma *dw = to_dw_dma(dwc->chan.device);
> -	u32 block;
> -
> -	/* Always in bytes for iDMA 32-bit */
> -	if (dw->pdata->is_idma32)
> -		width = 0;
> -
> -	if ((bytes >> width) > dwc->block_size) {
> -		block = dwc->block_size;
> -		*len = block << width;
> -	} else {
> -		block = bytes >> width;
> -		*len = bytes;
> -	}
> -
> -	return block;
> -}
> -
> -static size_t block2bytes(struct dw_dma_chan *dwc, u32 block, u32 width)
> -{
> -	struct dw_dma *dw = to_dw_dma(dwc->chan.device);
> -
> -	if (dw->pdata->is_idma32)
> -		return IDMA32C_CTLH_BLOCK_TS(block);
> -
> -	return DWC_CTLH_BLOCK_TS(block) << width;
> -}
> -
>  /*----------------------------------------------------------------------*/
>  
>  /* Perform single block transfer */
> @@ -389,10 +319,11 @@ static void dwc_complete_all(struct dw_dma *dw, struct dw_dma_chan *dwc)
>  /* Returns how many bytes were already received from source */
>  static inline u32 dwc_get_sent(struct dw_dma_chan *dwc)
>  {
> +	struct dw_dma *dw = to_dw_dma(dwc->chan.device);
>  	u32 ctlhi = channel_readl(dwc, CTL_HI);
>  	u32 ctllo = channel_readl(dwc, CTL_LO);
>  
> -	return block2bytes(dwc, ctlhi, ctllo >> 4 & 7);
> +	return dw->block2bytes(dwc, ctlhi, ctllo >> 4 & 7);
>  }
>  
>  static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
> @@ -649,7 +580,7 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
>  	unsigned int		src_width;
>  	unsigned int		dst_width;
>  	unsigned int		data_width = dw->pdata->data_width[m_master];
> -	u32			ctllo;
> +	u32			ctllo, ctlhi;
>  	u8			lms = DWC_LLP_LMS(m_master);
>  
>  	dev_vdbg(chan2dev(chan),
> @@ -678,10 +609,12 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
>  		if (!desc)
>  			goto err_desc_get;
>  
> +		ctlhi = dw->bytes2block(dwc, len - offset, src_width, &xfer_count);
> +
>  		lli_write(desc, sar, src + offset);
>  		lli_write(desc, dar, dest + offset);
>  		lli_write(desc, ctllo, ctllo);
> -		lli_write(desc, ctlhi, bytes2block(dwc, len - offset, src_width, &xfer_count));
> +		lli_write(desc, ctlhi, ctlhi);
>  		desc->len = xfer_count;
>  
>  		if (!first) {
> @@ -719,7 +652,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
>  	struct dma_slave_config	*sconfig = &dwc->dma_sconfig;
>  	struct dw_desc		*prev;
>  	struct dw_desc		*first;
> -	u32			ctllo;
> +	u32			ctllo, ctlhi;
>  	u8			m_master = dwc->dws.m_master;
>  	u8			lms = DWC_LLP_LMS(m_master);
>  	dma_addr_t		reg;
> @@ -766,9 +699,11 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
>  			if (!desc)
>  				goto err_desc_get;
>  
> +			ctlhi = dw->bytes2block(dwc, len, mem_width, &dlen);
> +
>  			lli_write(desc, sar, mem);
>  			lli_write(desc, dar, reg);
> -			lli_write(desc, ctlhi, bytes2block(dwc, len, mem_width, &dlen));
> +			lli_write(desc, ctlhi, ctlhi);
>  			lli_write(desc, ctllo, ctllo | DWC_CTLL_SRC_WIDTH(mem_width));
>  			desc->len = dlen;
>  
> @@ -812,9 +747,11 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
>  			if (!desc)
>  				goto err_desc_get;
>  
> +			ctlhi = dw->bytes2block(dwc, len, reg_width, &dlen);
> +
>  			lli_write(desc, sar, reg);
>  			lli_write(desc, dar, mem);
> -			lli_write(desc, ctlhi, bytes2block(dwc, len, reg_width, &dlen));
> +			lli_write(desc, ctlhi, ctlhi);
>  			mem_width = __ffs(data_width | mem | dlen);
>  			lli_write(desc, ctllo, ctllo | DWC_CTLL_DST_WIDTH(mem_width));
>  			desc->len = dlen;
> @@ -874,22 +811,12 @@ EXPORT_SYMBOL_GPL(dw_dma_filter);
>  static int dwc_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
>  {
>  	struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
> -	struct dma_slave_config *sc = &dwc->dma_sconfig;
>  	struct dw_dma *dw = to_dw_dma(chan->device);
> -	/*
> -	 * Fix sconfig's burst size according to dw_dmac. We need to convert
> -	 * them as:
> -	 * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3.
> -	 *
> -	 * NOTE: burst size 2 is not supported by DesignWare controller.
> -	 *       iDMA 32-bit supports it.
> -	 */
> -	u32 s = dw->pdata->is_idma32 ? 1 : 2;
>  
>  	memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig));
>  
> -	sc->src_maxburst = sc->src_maxburst > 1 ? fls(sc->src_maxburst) - s : 0;
> -	sc->dst_maxburst = sc->dst_maxburst > 1 ? fls(sc->dst_maxburst) - s : 0;
> +	dw->encode_maxburst(dwc, &dwc->dma_sconfig.src_maxburst);
> +	dw->encode_maxburst(dwc, &dwc->dma_sconfig.dst_maxburst);
>  
>  	return 0;
>  }
> @@ -898,16 +825,9 @@ static void dwc_chan_pause(struct dw_dma_chan *dwc, bool drain)
>  {
>  	struct dw_dma *dw = to_dw_dma(dwc->chan.device);
>  	unsigned int		count = 20;	/* timeout iterations */
> -	u32			cfglo;
>  
> -	cfglo = channel_readl(dwc, CFG_LO);
> -	if (dw->pdata->is_idma32) {
> -		if (drain)
> -			cfglo |= IDMA32C_CFGL_CH_DRAIN;
> -		else
> -			cfglo &= ~IDMA32C_CFGL_CH_DRAIN;
> -	}
> -	channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
> +	dw->suspend_chan(dwc, drain);
> +
>  	while (!(channel_readl(dwc, CFG_LO) & DWC_CFGL_FIFO_EMPTY) && count--)
>  		udelay(2);
>  
> @@ -1056,33 +976,7 @@ static void dwc_issue_pending(struct dma_chan *chan)
>  
>  /*----------------------------------------------------------------------*/
>  
> -/*
> - * Program FIFO size of channels.
> - *
> - * By default full FIFO (512 bytes) is assigned to channel 0. Here we
> - * slice FIFO on equal parts between channels.
> - */
> -static void idma32_fifo_partition(struct dw_dma *dw)
> -{
> -	u64 value = IDMA32C_FP_PSIZE_CH0(64) | IDMA32C_FP_PSIZE_CH1(64) |
> -		    IDMA32C_FP_UPDATE;
> -	u64 fifo_partition = 0;
> -
> -	if (!dw->pdata->is_idma32)
> -		return;
> -
> -	/* Fill FIFO_PARTITION low bits (Channels 0..1, 4..5) */
> -	fifo_partition |= value << 0;
> -
> -	/* Fill FIFO_PARTITION high bits (Channels 2..3, 6..7) */
> -	fifo_partition |= value << 32;
> -
> -	/* Program FIFO Partition registers - 128 bytes for each channel */
> -	idma32_writeq(dw, FIFO_PARTITION1, fifo_partition);
> -	idma32_writeq(dw, FIFO_PARTITION0, fifo_partition);
> -}
> -
> -static void dw_dma_off(struct dw_dma *dw)
> +void do_dma_off(struct dw_dma *dw)
>  {
>  	unsigned int i;
>  
> @@ -1101,7 +995,7 @@ static void dw_dma_off(struct dw_dma *dw)
>  		clear_bit(DW_DMA_IS_INITIALIZED, &dw->chan[i].flags);
>  }
>  
> -static void dw_dma_on(struct dw_dma *dw)
> +void do_dma_on(struct dw_dma *dw)
>  {
>  	dma_writel(dw, CFG, DW_CFG_DMA_EN);
>  }
> @@ -1137,7 +1031,7 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan)
>  
>  	/* Enable controller here if needed */
>  	if (!dw->in_use)
> -		dw_dma_on(dw);
> +		do_dma_on(dw);
>  	dw->in_use |= dwc->mask;
>  
>  	return 0;
> @@ -1175,30 +1069,25 @@ static void dwc_free_chan_resources(struct dma_chan *chan)
>  	/* Disable controller in case it was a last user */
>  	dw->in_use &= ~dwc->mask;
>  	if (!dw->in_use)
> -		dw_dma_off(dw);
> +		do_dma_off(dw);
>  
>  	dev_vdbg(chan2dev(chan), "%s: done\n", __func__);
>  }
>  
> -int dw_dma_probe(struct dw_dma_chip *chip)
> +int do_dma_probe(struct dw_dma_chip *chip)
>  {
> +	struct dw_dma *dw = chip->dw;
>  	struct dw_dma_platform_data *pdata;
> -	struct dw_dma		*dw;
>  	bool			autocfg = false;
>  	unsigned int		dw_params;
>  	unsigned int		i;
>  	int			err;
>  
> -	dw = devm_kzalloc(chip->dev, sizeof(*dw), GFP_KERNEL);
> -	if (!dw)
> -		return -ENOMEM;
> -
>  	dw->pdata = devm_kzalloc(chip->dev, sizeof(*dw->pdata), GFP_KERNEL);
>  	if (!dw->pdata)
>  		return -ENOMEM;
>  
>  	dw->regs = chip->regs;
> -	chip->dw = dw;
>  
>  	pm_runtime_get_sync(chip->dev);
>  
> @@ -1250,15 +1139,10 @@ int dw_dma_probe(struct dw_dma_chip *chip)
>  	dw->all_chan_mask = (1 << pdata->nr_channels) - 1;
>  
>  	/* Force dma off, just in case */
> -	dw_dma_off(dw);
> -
> -	idma32_fifo_partition(dw);
> +	dw->disable(dw);
>  
>  	/* Device and instance ID for IRQ and DMA pool */
> -	if (pdata->is_idma32)
> -		snprintf(dw->name, sizeof(dw->name), "idma32:dmac%d", chip->id);
> -	else
> -		snprintf(dw->name, sizeof(dw->name), "dw:dmac%d", chip->id);
> +	dw->set_device_name(dw, chip->id);
>  
>  	/* Create a pool of consistent memory blocks for hardware descriptors */
>  	dw->desc_pool = dmam_pool_create(dw->name, chip->dev,
> @@ -1382,16 +1266,15 @@ int dw_dma_probe(struct dw_dma_chip *chip)
>  	pm_runtime_put_sync_suspend(chip->dev);
>  	return err;
>  }
> -EXPORT_SYMBOL_GPL(dw_dma_probe);
>  
> -int dw_dma_remove(struct dw_dma_chip *chip)
> +int do_dma_remove(struct dw_dma_chip *chip)
>  {
>  	struct dw_dma		*dw = chip->dw;
>  	struct dw_dma_chan	*dwc, *_dwc;
>  
>  	pm_runtime_get_sync(chip->dev);
>  
> -	dw_dma_off(dw);
> +	do_dma_off(dw);
>  	dma_async_device_unregister(&dw->dma);
>  
>  	free_irq(chip->irq, dw);
> @@ -1406,27 +1289,24 @@ int dw_dma_remove(struct dw_dma_chip *chip)
>  	pm_runtime_put_sync_suspend(chip->dev);
>  	return 0;
>  }
> -EXPORT_SYMBOL_GPL(dw_dma_remove);
>  
> -int dw_dma_disable(struct dw_dma_chip *chip)
> +int do_dw_dma_disable(struct dw_dma_chip *chip)
>  {
>  	struct dw_dma *dw = chip->dw;
>  
> -	dw_dma_off(dw);
> +	dw->disable(dw);
>  	return 0;
>  }
> -EXPORT_SYMBOL_GPL(dw_dma_disable);
> +EXPORT_SYMBOL_GPL(do_dw_dma_disable);
>  
> -int dw_dma_enable(struct dw_dma_chip *chip)
> +int do_dw_dma_enable(struct dw_dma_chip *chip)
>  {
>  	struct dw_dma *dw = chip->dw;
>  
> -	idma32_fifo_partition(dw);
> -
> -	dw_dma_on(dw);
> +	dw->disable(dw);
>  	return 0;
>  }
> -EXPORT_SYMBOL_GPL(dw_dma_enable);
> +EXPORT_SYMBOL_GPL(do_dw_dma_enable);
>  
>  MODULE_LICENSE("GPL v2");
>  MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller core driver");
> diff --git a/drivers/dma/dw/dw.c b/drivers/dma/dw/dw.c
> new file mode 100644
> index 000000000000..998a9eeb561d
> --- /dev/null
> +++ b/drivers/dma/dw/dw.c
> @@ -0,0 +1,109 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (C) 2007-2008 Atmel Corporation
> +// Copyright (C) 2010-2011 ST Microelectronics
> +// Copyright (C) 2013,2018 Intel Corporation
> +
> +#include <linux/bitops.h>
> +#include <linux/errno.h>
> +#include <linux/slab.h>
> +
> +#include "internal.h"
> +
> +static void dw_dma_initialize_chan(struct dw_dma_chan *dwc)
> +{
> +	u32 cfghi = DWC_CFGH_FIFO_MODE;
> +	u32 cfglo = DWC_CFGL_CH_PRIOR(dwc->priority);
> +	bool hs_polarity = dwc->dws.hs_polarity;
> +
> +	cfghi |= DWC_CFGH_DST_PER(dwc->dws.dst_id);
> +	cfghi |= DWC_CFGH_SRC_PER(dwc->dws.src_id);
> +
> +	/* Set polarity of handshake interface */
> +	cfglo |= hs_polarity ? DWC_CFGL_HS_DST_POL | DWC_CFGL_HS_SRC_POL : 0;
> +
> +	channel_writel(dwc, CFG_LO, cfglo);
> +	channel_writel(dwc, CFG_HI, cfghi);
> +}
> +
> +static void dw_dma_suspend_chan(struct dw_dma_chan *dwc, bool drain)
> +{
> +	u32 cfglo = channel_readl(dwc, CFG_LO);
> +
> +	channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
> +}
> +
> +static u32 dw_dma_bytes2block(struct dw_dma_chan *dwc,
> +			      size_t bytes, unsigned int width, size_t *len)
> +{
> +	u32 block;
> +
> +	if ((bytes >> width) > dwc->block_size) {
> +		block = dwc->block_size;
> +		*len = block << width;
> +	} else {
> +		block = bytes >> width;
> +		*len = bytes;
> +	}
> +
> +	return block;
> +}
> +
> +static size_t dw_dma_block2bytes(struct dw_dma_chan *dwc, u32 block, u32 width)
> +{
> +	return DWC_CTLH_BLOCK_TS(block) << width;
> +}
> +
> +static void dw_dma_encode_maxburst(struct dw_dma_chan *dwc, u32 *maxburst)
> +{
> +	/*
> +	 * Fix burst size according to dw_dmac. We need to convert them as:
> +	 * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3.
> +	 */
> +	*maxburst = *maxburst > 1 ? fls(*maxburst) - 2 : 0;
> +}
> +
> +static void dw_dma_set_device_name(struct dw_dma *dw, int id)
> +{
> +	snprintf(dw->name, sizeof(dw->name), "dw:dmac%d", id);
> +}
> +
> +static void dw_dma_disable(struct dw_dma *dw)
> +{
> +	do_dma_off(dw);
> +}
> +
> +static void dw_dma_enable(struct dw_dma *dw)
> +{
> +	do_dma_on(dw);
> +}
> +
> +int dw_dma_probe(struct dw_dma_chip *chip)
> +{
> +	struct dw_dma *dw;
> +
> +	dw = devm_kzalloc(chip->dev, sizeof(*dw), GFP_KERNEL);
> +	if (!dw)
> +		return -ENOMEM;
> +
> +	/* Channel operations */
> +	dw->initialize_chan = dw_dma_initialize_chan;
> +	dw->suspend_chan = dw_dma_suspend_chan;
> +	dw->encode_maxburst = dw_dma_encode_maxburst;
> +	dw->bytes2block = dw_dma_bytes2block;
> +	dw->block2bytes = dw_dma_block2bytes;
> +
> +	/* Device operations */
> +	dw->set_device_name = dw_dma_set_device_name;
> +	dw->disable = dw_dma_disable;
> +	dw->enable = dw_dma_enable;
> +
> +	chip->dw = dw;
> +	return do_dma_probe(chip);
> +}
> +EXPORT_SYMBOL_GPL(dw_dma_probe);
> +
> +int dw_dma_remove(struct dw_dma_chip *chip)
> +{
> +	return do_dma_remove(chip);
> +}
> +EXPORT_SYMBOL_GPL(dw_dma_remove);
> diff --git a/drivers/dma/dw/idma32.c b/drivers/dma/dw/idma32.c
> new file mode 100644
> index 000000000000..d06fb00fb862
> --- /dev/null
> +++ b/drivers/dma/dw/idma32.c
> @@ -0,0 +1,137 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (C) 2013,2018 Intel Corporation
> +
> +#include <linux/bitops.h>
> +#include <linux/errno.h>
> +#include <linux/slab.h>
> +
> +#include "internal.h"
> +
> +static void idma32_initialize_chan(struct dw_dma_chan *dwc)
> +{
> +	u32 cfghi = 0;
> +	u32 cfglo = 0;
> +
> +	/* Set default burst alignment */
> +	cfglo |= IDMA32C_CFGL_DST_BURST_ALIGN | IDMA32C_CFGL_SRC_BURST_ALIGN;
> +
> +	/* Low 4 bits of the request lines */
> +	cfghi |= IDMA32C_CFGH_DST_PER(dwc->dws.dst_id & 0xf);
> +	cfghi |= IDMA32C_CFGH_SRC_PER(dwc->dws.src_id & 0xf);
> +
> +	/* Request line extension (2 bits) */
> +	cfghi |= IDMA32C_CFGH_DST_PER_EXT(dwc->dws.dst_id >> 4 & 0x3);
> +	cfghi |= IDMA32C_CFGH_SRC_PER_EXT(dwc->dws.src_id >> 4 & 0x3);
> +
> +	channel_writel(dwc, CFG_LO, cfglo);
> +	channel_writel(dwc, CFG_HI, cfghi);
> +}
> +
> +static void idma32_suspend_chan(struct dw_dma_chan *dwc, bool drain)
> +{
> +	u32 cfglo = channel_readl(dwc, CFG_LO);
> +
> +	if (drain)
> +		cfglo |= IDMA32C_CFGL_CH_DRAIN;
> +	else
> +		cfglo &= ~IDMA32C_CFGL_CH_DRAIN;
> +
> +	channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
> +}
> +
> +static u32 idma32_bytes2block(struct dw_dma_chan *dwc,
> +			      size_t bytes, unsigned int width, size_t *len)
> +{
> +	u32 block;
> +
> +	if (bytes > dwc->block_size) {
> +		block = dwc->block_size;
> +		*len = dwc->block_size;
> +	} else {
> +		block = bytes;
> +		*len = bytes;
> +	}
> +
> +	return block;
> +}
> +
> +static size_t idma32_block2bytes(struct dw_dma_chan *dwc, u32 block, u32 width)
> +{
> +	return IDMA32C_CTLH_BLOCK_TS(block);
> +}
> +
> +static void idma32_encode_maxburst(struct dw_dma_chan *dwc, u32 *maxburst)
> +{
> +	*maxburst = *maxburst > 1 ? fls(*maxburst) - 1 : 0;
> +}
> +
> +static void idma32_set_device_name(struct dw_dma *dw, int id)
> +{
> +	snprintf(dw->name, sizeof(dw->name), "idma32:dmac%d", id);
> +}
> +
> +/*
> + * Program FIFO size of channels.
> + *
> + * By default full FIFO (512 bytes) is assigned to channel 0. Here we
> + * slice FIFO on equal parts between channels.
> + */
> +static void idma32_fifo_partition(struct dw_dma *dw)
> +{
> +	u64 value = IDMA32C_FP_PSIZE_CH0(64) | IDMA32C_FP_PSIZE_CH1(64) |
> +		    IDMA32C_FP_UPDATE;
> +	u64 fifo_partition = 0;
> +
> +	/* Fill FIFO_PARTITION low bits (Channels 0..1, 4..5) */
> +	fifo_partition |= value << 0;
> +
> +	/* Fill FIFO_PARTITION high bits (Channels 2..3, 6..7) */
> +	fifo_partition |= value << 32;
> +
> +	/* Program FIFO Partition registers - 128 bytes for each channel */
> +	idma32_writeq(dw, FIFO_PARTITION1, fifo_partition);
> +	idma32_writeq(dw, FIFO_PARTITION0, fifo_partition);
> +}
> +
> +static void idma32_disable(struct dw_dma *dw)
> +{
> +	do_dma_off(dw);
> +	idma32_fifo_partition(dw);
> +}
> +
> +static void idma32_enable(struct dw_dma *dw)
> +{
> +	idma32_fifo_partition(dw);
> +	do_dma_on(dw);
> +}
> +
> +int idma32_dma_probe(struct dw_dma_chip *chip)
> +{
> +	struct dw_dma *dw;
> +
> +	dw = devm_kzalloc(chip->dev, sizeof(*dw), GFP_KERNEL);
> +	if (!dw)
> +		return -ENOMEM;
> +
> +	/* Channel operations */
> +	dw->initialize_chan = idma32_initialize_chan;
> +	dw->suspend_chan = idma32_suspend_chan;
> +	dw->encode_maxburst = idma32_encode_maxburst;
> +	dw->bytes2block = idma32_bytes2block;
> +	dw->block2bytes = idma32_block2bytes;
> +
> +	/* Device operations */
> +	dw->set_device_name = idma32_set_device_name;
> +	dw->disable = idma32_disable;
> +	dw->enable = idma32_enable;
> +
> +	chip->dw = dw;
> +	return do_dma_probe(chip);
> +}
> +EXPORT_SYMBOL_GPL(idma32_dma_probe);
> +
> +int idma32_dma_remove(struct dw_dma_chip *chip)
> +{
> +	return do_dma_remove(chip);
> +}
> +EXPORT_SYMBOL_GPL(idma32_dma_remove);
> diff --git a/drivers/dma/dw/internal.h b/drivers/dma/dw/internal.h
> index 41439732ff6b..1f2ddfe745bb 100644
> --- a/drivers/dma/dw/internal.h
> +++ b/drivers/dma/dw/internal.h
> @@ -15,8 +15,14 @@
>  
>  #include "regs.h"
>  
> -int dw_dma_disable(struct dw_dma_chip *chip);
> -int dw_dma_enable(struct dw_dma_chip *chip);
> +int do_dma_probe(struct dw_dma_chip *chip);
> +int do_dma_remove(struct dw_dma_chip *chip);
> +
> +void do_dma_on(struct dw_dma *dw);
> +void do_dma_off(struct dw_dma *dw);
> +
> +int do_dw_dma_disable(struct dw_dma_chip *chip);
> +int do_dw_dma_enable(struct dw_dma_chip *chip);
>  
>  extern bool dw_dma_filter(struct dma_chan *chan, void *param);
>  
> diff --git a/drivers/dma/dw/pci.c b/drivers/dma/dw/pci.c
> index 61f2274f6dd4..f5ea58cc027b 100644
> --- a/drivers/dma/dw/pci.c
> +++ b/drivers/dma/dw/pci.c
> @@ -15,11 +15,19 @@
>  
>  #include "internal.h"
>  
> -static struct dw_dma_platform_data mrfld_pdata = {
> +static struct dw_dma_pci_data {
> +	const struct dw_dma_platform_data *pdata;
> +	int (*probe)(struct dw_dma_chip *chip);
> +};
> +
> +static const struct dw_dma_pci_data dw_pci_data = {
> +	.probe = dw_dma_probe,
> +};
> +
> +static const struct dw_dma_platform_data idma32_pdata = {
>  	.nr_channels = 8,
>  	.is_private = true,
>  	.is_memcpy = true,
> -	.is_idma32 = true,
>  	.chan_allocation_order = CHAN_ALLOCATION_ASCENDING,
>  	.chan_priority = CHAN_PRIORITY_ASCENDING,
>  	.block_size = 131071,
> @@ -28,9 +36,14 @@ static struct dw_dma_platform_data mrfld_pdata = {
>  	.multi_block = {true, true, true, true, true, true, true, true},
>  };
>  
> +static const struct dw_dma_pci_data idma32_pci_data = {
> +	.pdata = &idma32_pdata,
> +	.probe = idma32_dma_probe,
> +};
> +
>  static int dw_pci_probe(struct pci_dev *pdev, const struct pci_device_id *pid)
>  {
> -	const struct dw_dma_platform_data *pdata = (void *)pid->driver_data;
> +	const struct dw_dma_pci_data *data = (void *)pid->driver_data;
>  	struct dw_dma_chip *chip;
>  	int ret;
>  
> @@ -63,9 +76,9 @@ static int dw_pci_probe(struct pci_dev *pdev, const struct pci_device_id *pid)
>  	chip->id = pdev->devfn;
>  	chip->regs = pcim_iomap_table(pdev)[0];
>  	chip->irq = pdev->irq;
> -	chip->pdata = pdata;
> +	chip->pdata = data->pdata;
>  
> -	ret = dw_dma_probe(chip);
> +	ret = data->probe(chip);
>  	if (ret)
>  		return ret;
>  
> @@ -91,7 +104,7 @@ static int dw_pci_suspend_late(struct device *dev)
>  	struct pci_dev *pci = to_pci_dev(dev);
>  	struct dw_dma_chip *chip = pci_get_drvdata(pci);
>  
> -	return dw_dma_disable(chip);
> +	return do_dw_dma_disable(chip);
>  };
>  
>  static int dw_pci_resume_early(struct device *dev)
> @@ -99,7 +112,7 @@ static int dw_pci_resume_early(struct device *dev)
>  	struct pci_dev *pci = to_pci_dev(dev);
>  	struct dw_dma_chip *chip = pci_get_drvdata(pci);
>  
> -	return dw_dma_enable(chip);
> +	return do_dw_dma_enable(chip);
>  };
>  
>  #endif /* CONFIG_PM_SLEEP */
> @@ -110,24 +123,24 @@ static const struct dev_pm_ops dw_pci_dev_pm_ops = {
>  
>  static const struct pci_device_id dw_pci_id_table[] = {
>  	/* Medfield (GPDMA) */
> -	{ PCI_VDEVICE(INTEL, 0x0827) },
> +	{ PCI_VDEVICE(INTEL, 0x0827), (kernel_ulong_t)&dw_pci_data },
>  
>  	/* BayTrail */
> -	{ PCI_VDEVICE(INTEL, 0x0f06) },
> -	{ PCI_VDEVICE(INTEL, 0x0f40) },
> +	{ PCI_VDEVICE(INTEL, 0x0f06), (kernel_ulong_t)&dw_pci_data },
> +	{ PCI_VDEVICE(INTEL, 0x0f40), (kernel_ulong_t)&dw_pci_data },
>  
> -	/* Merrifield iDMA 32-bit (GPDMA) */
> -	{ PCI_VDEVICE(INTEL, 0x11a2), (kernel_ulong_t)&mrfld_pdata },
> +	/* Merrifield */
> +	{ PCI_VDEVICE(INTEL, 0x11a2), (kernel_ulong_t)&idma32_pci_data },
>  
>  	/* Braswell */
> -	{ PCI_VDEVICE(INTEL, 0x2286) },
> -	{ PCI_VDEVICE(INTEL, 0x22c0) },
> +	{ PCI_VDEVICE(INTEL, 0x2286), (kernel_ulong_t)&dw_pci_data },
> +	{ PCI_VDEVICE(INTEL, 0x22c0), (kernel_ulong_t)&dw_pci_data },
>  
>  	/* Haswell */
> -	{ PCI_VDEVICE(INTEL, 0x9c60) },
> +	{ PCI_VDEVICE(INTEL, 0x9c60), (kernel_ulong_t)&dw_pci_data },
>  
>  	/* Broadwell */
> -	{ PCI_VDEVICE(INTEL, 0x9ce0) },
> +	{ PCI_VDEVICE(INTEL, 0x9ce0), (kernel_ulong_t)&dw_pci_data },
>  
>  	{ }
>  };
> diff --git a/drivers/dma/dw/platform.c b/drivers/dma/dw/platform.c
> index f01b2c173fa6..6bf46c9b7ee4 100644
> --- a/drivers/dma/dw/platform.c
> +++ b/drivers/dma/dw/platform.c
> @@ -258,7 +258,7 @@ static void dw_shutdown(struct platform_device *pdev)
>  	struct dw_dma_chip *chip = platform_get_drvdata(pdev);
>  
>  	/*
> -	 * We have to call dw_dma_disable() to stop any ongoing transfer. On
> +	 * We have to call do_dw_dma_disable() to stop any ongoing transfer. On
>  	 * some platforms we can't do that since DMA device is powered off.
>  	 * Moreover we have no possibility to check if the platform is affected
>  	 * or not. That's why we call pm_runtime_get_sync() / pm_runtime_put()
> @@ -267,7 +267,7 @@ static void dw_shutdown(struct platform_device *pdev)
>  	 * used by the driver.
>  	 */
>  	pm_runtime_get_sync(chip->dev);
> -	dw_dma_disable(chip);
> +	do_dw_dma_disable(chip);
>  	pm_runtime_put_sync_suspend(chip->dev);
>  
>  	clk_disable_unprepare(chip->clk);
> @@ -297,7 +297,7 @@ static int dw_suspend_late(struct device *dev)
>  {
>  	struct dw_dma_chip *chip = dev_get_drvdata(dev);
>  
> -	dw_dma_disable(chip);
> +	do_dw_dma_disable(chip);
>  	clk_disable_unprepare(chip->clk);
>  
>  	return 0;
> @@ -312,7 +312,7 @@ static int dw_resume_early(struct device *dev)
>  	if (ret)
>  		return ret;
>  
> -	return dw_dma_enable(chip);
> +	return do_dw_dma_enable(chip);
>  }
>  
>  #endif /* CONFIG_PM_SLEEP */
> diff --git a/drivers/dma/dw/regs.h b/drivers/dma/dw/regs.h
> index 09e7dfdbb790..90e46e69c047 100644
> --- a/drivers/dma/dw/regs.h
> +++ b/drivers/dma/dw/regs.h
> @@ -308,6 +308,19 @@ struct dw_dma {
>  	u8			all_chan_mask;
>  	u8			in_use;
>  
> +	/* Channel operations */
> +	void	(*initialize_chan)(struct dw_dma_chan *dwc);
> +	void	(*suspend_chan)(struct dw_dma_chan *dwc, bool drain);
> +	void	(*encode_maxburst)(struct dw_dma_chan *dwc, u32 *maxburst);
> +	u32	(*bytes2block)(struct dw_dma_chan *dwc, size_t bytes,
> +			       unsigned int width, size_t *len);
> +	size_t	(*block2bytes)(struct dw_dma_chan *dwc, u32 block, u32 width);
> +
> +	/* Device operations */
> +	void (*set_device_name)(struct dw_dma *dw, int id);
> +	void (*disable)(struct dw_dma *dw);
> +	void (*enable)(struct dw_dma *dw);
> +
>  	/* platform data */
>  	struct dw_dma_platform_data	*pdata;
>  };
> diff --git a/include/linux/dma/dw.h b/include/linux/dma/dw.h
> index e166cac8e870..d643d331c20e 100644
> --- a/include/linux/dma/dw.h
> +++ b/include/linux/dma/dw.h
> @@ -45,9 +45,13 @@ struct dw_dma_chip {
>  #if IS_ENABLED(CONFIG_DW_DMAC_CORE)
>  int dw_dma_probe(struct dw_dma_chip *chip);
>  int dw_dma_remove(struct dw_dma_chip *chip);
> +int idma32_dma_probe(struct dw_dma_chip *chip);
> +int idma32_dma_remove(struct dw_dma_chip *chip);
>  #else
>  static inline int dw_dma_probe(struct dw_dma_chip *chip) { return -ENODEV; }
>  static inline int dw_dma_remove(struct dw_dma_chip *chip) { return 0; }
> +static inline int idma32_dma_probe(struct dw_dma_chip *chip) { return -ENODEV; }
> +static inline int idma32_dma_remove(struct dw_dma_chip *chip) { return 0; }
>  #endif /* CONFIG_DW_DMAC_CORE */
>  
>  #endif /* _DMA_DW_H */
> diff --git a/include/linux/platform_data/dma-dw.h b/include/linux/platform_data/dma-dw.h
> index 896cb71a382c..e69e415d0d98 100644
> --- a/include/linux/platform_data/dma-dw.h
> +++ b/include/linux/platform_data/dma-dw.h
> @@ -41,7 +41,6 @@ struct dw_dma_slave {
>   * @is_private: The device channels should be marked as private and not for
>   *	by the general purpose DMA channel allocator.
>   * @is_memcpy: The device channels do support memory-to-memory transfers.
> - * @is_idma32: The type of the DMA controller is iDMA32
>   * @chan_allocation_order: Allocate channels starting from 0 or 7
>   * @chan_priority: Set channel priority increasing from 0 to 7 or 7 to 0.
>   * @block_size: Maximum block size supported by the controller
> @@ -54,7 +53,6 @@ struct dw_dma_platform_data {
>  	unsigned int	nr_channels;
>  	bool		is_private;
>  	bool		is_memcpy;
> -	bool		is_idma32;
>  #define CHAN_ALLOCATION_ASCENDING	0	/* zero to seven */
>  #define CHAN_ALLOCATION_DESCENDING	1	/* seven to zero */
>  	unsigned char	chan_allocation_order;
> -- 
> 2.19.2
>