Commit f776076b authored by Arnd Bergmann's avatar Arnd Bergmann Committed by Vinod Koul
Browse files

dmaengine: dw_dmac: simplify master selection 



The patch to add the common DMA binding added a dummy dw_dma_slave
structure into the dw_dma_chan structure in order to configure the
masters correctly. It turns out that this can be simplified if we
pick the DMA masters in the dwc_alloc_chan_resources function instead
and save them in the dw_dma_chan structure directly.

This could be simplified further once all users that today use
dw_dma_slave for configuration get converted to device tree based
setup instead.

Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarVinod Koul <vinod.koul@intel.com>
parent bd2e6b66

drivers/dma/dw_dmac.c

+29 −47
Original line number Diff line number Diff line
@@ -49,29 +49,22 @@ static inline unsigned int dwc_get_sms(struct dw_dma_slave *slave) 
	return slave ? slave->src_master : 1;

}



#define SRC_MASTER	0

#define DST_MASTER	1



static inline unsigned int dwc_get_master(struct dma_chan *chan, int master)

static inline void dwc_set_masters(struct dw_dma_chan *dwc)

{

	struct dw_dma *dw = to_dw_dma(chan->device);

	struct dw_dma_slave *dws = chan->private;

	unsigned int m;



	if (master == SRC_MASTER)

		m = dwc_get_sms(dws);

	else

		m = dwc_get_dms(dws);

	struct dw_dma *dw = to_dw_dma(dwc->chan.device);

	struct dw_dma_slave *dws = dwc->chan.private;

	unsigned char mmax = dw->nr_masters - 1;



	return min_t(unsigned int, dw->nr_masters - 1, m);

	if (dwc->request_line == ~0) {

		dwc->src_master = min_t(unsigned char, mmax, dwc_get_sms(dws));

		dwc->dst_master = min_t(unsigned char, mmax, dwc_get_dms(dws));

	}

}



#define DWC_DEFAULT_CTLLO(_chan) ({				\

		struct dw_dma_chan *_dwc = to_dw_dma_chan(_chan);	\

		struct dma_slave_config	*_sconfig = &_dwc->dma_sconfig;	\

		bool _is_slave = is_slave_direction(_dwc->direction);	\

		int _dms = dwc_get_master(_chan, DST_MASTER);		\

		int _sms = dwc_get_master(_chan, SRC_MASTER);		\

		u8 _smsize = _is_slave ? _sconfig->src_maxburst :	\

			DW_DMA_MSIZE_16;			\

		u8 _dmsize = _is_slave ? _sconfig->dst_maxburst :	\
@@ -81,8 +74,8 @@ static inline unsigned int dwc_get_master(struct dma_chan *chan, int master) 
		 | DWC_CTLL_SRC_MSIZE(_smsize)			\

		 | DWC_CTLL_LLP_D_EN				\

		 | DWC_CTLL_LLP_S_EN				\

		 | DWC_CTLL_DMS(_dms)				\

		 | DWC_CTLL_SMS(_sms));				\

		 | DWC_CTLL_DMS(_dwc->dst_master)		\

		 | DWC_CTLL_SMS(_dwc->src_master));		\

	})



/*
@@ -92,13 +85,6 @@ static inline unsigned int dwc_get_master(struct dma_chan *chan, int master) 
 */

#define NR_DESCS_PER_CHANNEL	64



static inline unsigned int dwc_get_data_width(struct dma_chan *chan, int master)

{

	struct dw_dma *dw = to_dw_dma(chan->device);



	return dw->data_width[dwc_get_master(chan, master)];

}



/*----------------------------------------------------------------------*/



static struct device *chan2dev(struct dma_chan *chan)
@@ -172,13 +158,7 @@ static void dwc_initialize(struct dw_dma_chan *dwc) 
	if (dwc->initialized == true)

		return;



	if (dws && dws->cfg_hi == ~0 && dws->cfg_lo == ~0) {

		/* Autoconfigure based on request line from DT */

		if (dwc->direction == DMA_MEM_TO_DEV)

			cfghi = DWC_CFGH_DST_PER(dwc->request_line);

		else if (dwc->direction == DMA_DEV_TO_MEM)

			cfghi = DWC_CFGH_SRC_PER(dwc->request_line);

	} else if (dws) {

	if (dws) {

		/*

		 * We need controller-specific data to set up slave

		 * transfers.
@@ -189,9 +169,9 @@ static void dwc_initialize(struct dw_dma_chan *dwc) 
		cfglo |= dws->cfg_lo & ~DWC_CFGL_CH_PRIOR_MASK;

	} else {

		if (dwc->direction == DMA_MEM_TO_DEV)

			cfghi = DWC_CFGH_DST_PER(dwc->dma_sconfig.slave_id);

			cfghi = DWC_CFGH_DST_PER(dwc->request_line);

		else if (dwc->direction == DMA_DEV_TO_MEM)

			cfghi = DWC_CFGH_SRC_PER(dwc->dma_sconfig.slave_id);

			cfghi = DWC_CFGH_SRC_PER(dwc->request_line);

	}



	channel_writel(dwc, CFG_LO, cfglo);
@@ -745,6 +725,7 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, 
		size_t len, unsigned long flags)

{

	struct dw_dma_chan	*dwc = to_dw_dma_chan(chan);

	struct dw_dma		*dw = to_dw_dma(chan->device);

	struct dw_desc		*desc;

	struct dw_desc		*first;

	struct dw_desc		*prev;
@@ -767,8 +748,8 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, 


	dwc->direction = DMA_MEM_TO_MEM;



	data_width = min_t(unsigned int, dwc_get_data_width(chan, SRC_MASTER),

			   dwc_get_data_width(chan, DST_MASTER));

	data_width = min_t(unsigned int, dw->data_width[dwc->src_master],

			   dw->data_width[dwc->dst_master]);



	src_width = dst_width = min_t(unsigned int, data_width,

				      dwc_fast_fls(src | dest | len));
@@ -826,6 +807,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, 
		unsigned long flags, void *context)

{

	struct dw_dma_chan	*dwc = to_dw_dma_chan(chan);

	struct dw_dma		*dw = to_dw_dma(chan->device);

	struct dma_slave_config	*sconfig = &dwc->dma_sconfig;

	struct dw_desc		*prev;

	struct dw_desc		*first;
@@ -859,7 +841,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, 
		ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_M2P) :

			DWC_CTLL_FC(DW_DMA_FC_D_M2P);



		data_width = dwc_get_data_width(chan, SRC_MASTER);

		data_width = dw->data_width[dwc->src_master];



		for_each_sg(sgl, sg, sg_len, i) {

			struct dw_desc	*desc;
@@ -919,7 +901,7 @@ slave_sg_todev_fill_desc: 
		ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_P2M) :

			DWC_CTLL_FC(DW_DMA_FC_D_P2M);



		data_width = dwc_get_data_width(chan, DST_MASTER);

		data_width = dw->data_width[dwc->dst_master];



		for_each_sg(sgl, sg, sg_len, i) {

			struct dw_desc	*desc;
@@ -1020,6 +1002,10 @@ set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig) 
	memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig));

	dwc->direction = sconfig->direction;



	/* Take the request line from slave_id member */

	if (dwc->request_line == ~0)

		dwc->request_line = sconfig->slave_id;



	convert_burst(&dwc->dma_sconfig.src_maxburst);

	convert_burst(&dwc->dma_sconfig.dst_maxburst);

	convert_slave_id(dwc);
@@ -1170,6 +1156,8 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan) 
	 * doesn't mean what you think it means), and status writeback.

	 */



	dwc_set_masters(dwc);



	spin_lock_irqsave(&dwc->lock, flags);

	i = dwc->descs_allocated;

	while (dwc->descs_allocated < NR_DESCS_PER_CHANNEL) {
@@ -1227,6 +1215,7 @@ static void dwc_free_chan_resources(struct dma_chan *chan) 
	list_splice_init(&dwc->free_list, &list);

	dwc->descs_allocated = 0;

	dwc->initialized = false;

	dwc->request_line = ~0;



	/* Disable interrupts */

	channel_clear_bit(dw, MASK.XFER, dwc->mask);
@@ -1254,23 +1243,15 @@ struct dw_dma_of_filter_args { 
static bool dw_dma_of_filter(struct dma_chan *chan, void *param)

{

	struct dw_dma_chan *dwc = to_dw_dma_chan(chan);

	struct dw_dma *dw = to_dw_dma(chan->device);

	struct dw_dma_of_filter_args *fargs = param;

	struct dw_dma_slave *dws = &dwc->slave;



	/* Ensure the device matches our channel */

        if (chan->device != &fargs->dw->dma)

                return false;



	dws->dma_dev	= dw->dma.dev;

	dws->cfg_hi	= ~0;

	dws->cfg_lo	= ~0;

	dws->src_master	= fargs->src;

	dws->dst_master	= fargs->dst;



	dwc->request_line = fargs->req;



	chan->private = dws;

	dwc->src_master	= fargs->src;

	dwc->dst_master	= fargs->dst;



	return true;

}
@@ -1784,6 +1765,7 @@ static int dw_probe(struct platform_device *pdev) 
		channel_clear_bit(dw, CH_EN, dwc->mask);



		dwc->direction = DMA_TRANS_NONE;

		dwc->request_line = ~0;



		/* Hardware configuration */

		if (autocfg) {

drivers/dma/dw_dmac_regs.h

+4 −1
Original line number Diff line number Diff line
@@ -212,8 +212,11 @@ struct dw_dma_chan { 
	/* hardware configuration */

	unsigned int		block_size;

	bool			nollp;



	/* custom slave configuration */

	unsigned int		request_line;

	struct dw_dma_slave	slave;

	unsigned char		src_master;

	unsigned char		dst_master;



	/* configuration passed via DMA_SLAVE_CONFIG */

	struct dma_slave_config dma_sconfig;

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