1 files changed, 112 insertions, 80 deletions

diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c
index c599558faed..2e5deaa82b6 100644
--- a/drivers/dma/dw_dmac.c
+++ b/drivers/dma/dw_dmac.c
@@ -25,6 +25,8 @@
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
+#include <linux/acpi.h>
+#include <linux/acpi_dma.h>
 
 #include "dw_dmac_regs.h"
 #include "dmaengine.h"
@@ -49,29 +51,22 @@ 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 +76,8 @@ 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 +87,6 @@ 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 +160,7 @@ 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 +171,9 @@ 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);
@@ -473,16 +455,16 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
 			(unsigned long long)llp);
 
 	list_for_each_entry_safe(desc, _desc, &dwc->active_list, desc_node) {
-		/* initial residue value */
+		/* Initial residue value */
 		dwc->residue = desc->total_len;
 
-		/* check first descriptors addr */
+		/* Check first descriptors addr */
 		if (desc->txd.phys == llp) {
 			spin_unlock_irqrestore(&dwc->lock, flags);
 			return;
 		}
 
-		/* check first descriptors llp */
+		/* Check first descriptors llp */
 		if (desc->lli.llp == llp) {
 			/* This one is currently in progress */
 			dwc->residue -= dwc_get_sent(dwc);
@@ -588,7 +570,7 @@ inline dma_addr_t dw_dma_get_dst_addr(struct dma_chan *chan)
 }
 EXPORT_SYMBOL(dw_dma_get_dst_addr);
 
-/* called with dwc->lock held and all DMAC interrupts disabled */
+/* Called with dwc->lock held and all DMAC interrupts disabled */
 static void dwc_handle_cyclic(struct dw_dma *dw, struct dw_dma_chan *dwc,
 		u32 status_err, u32 status_xfer)
 {
@@ -626,7 +608,7 @@ static void dwc_handle_cyclic(struct dw_dma *dw, struct dw_dma_chan *dwc,
 
 		dwc_chan_disable(dw, dwc);
 
-		/* make sure DMA does not restart by loading a new list */
+		/* Make sure DMA does not restart by loading a new list */
 		channel_writel(dwc, LLP, 0);
 		channel_writel(dwc, CTL_LO, 0);
 		channel_writel(dwc, CTL_HI, 0);
@@ -745,6 +727,7 @@ 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 +750,8 @@ 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 +809,7 @@ 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 +843,7 @@ 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 +903,7 @@ 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;
@@ -1013,6 +997,10 @@ 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);
 
@@ -1022,10 +1010,11 @@ set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
 static inline void dwc_chan_pause(struct dw_dma_chan *dwc)
 {
 	u32 cfglo = channel_readl(dwc, CFG_LO);
+	unsigned int count = 20;	/* timeout iterations */
 
 	channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
-	while (!(channel_readl(dwc, CFG_LO) & DWC_CFGL_FIFO_EMPTY))
-		cpu_relax();
+	while (!(channel_readl(dwc, CFG_LO) & DWC_CFGL_FIFO_EMPTY) && count--)
+		udelay(2);
 
 	dwc->paused = true;
 }
@@ -1161,6 +1150,8 @@ 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) {
@@ -1218,6 +1209,7 @@ 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);
@@ -1233,42 +1225,36 @@ static void dwc_free_chan_resources(struct dma_chan *chan)
 	dev_vdbg(chan2dev(chan), "%s: done\n", __func__);
 }
 
-struct dw_dma_filter_args {
+/*----------------------------------------------------------------------*/
+
+struct dw_dma_of_filter_args {
 	struct dw_dma *dw;
 	unsigned int req;
 	unsigned int src;
 	unsigned int dst;
 };
 
-static bool dw_dma_generic_filter(struct dma_chan *chan, void *param)
+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_filter_args *fargs = param;
-	struct dw_dma_slave *dws = &dwc->slave;
+	struct dw_dma_of_filter_args *fargs = param;
 
-	/* ensure the device matches our channel */
+	/* 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;
 }
 
-static struct dma_chan *dw_dma_xlate(struct of_phandle_args *dma_spec,
-					 struct of_dma *ofdma)
+static struct dma_chan *dw_dma_of_xlate(struct of_phandle_args *dma_spec,
+					struct of_dma *ofdma)
 {
 	struct dw_dma *dw = ofdma->of_dma_data;
-	struct dw_dma_filter_args fargs = {
+	struct dw_dma_of_filter_args fargs = {
 		.dw = dw,
 	};
 	dma_cap_mask_t cap;
@@ -1276,9 +1262,9 @@ static struct dma_chan *dw_dma_xlate(struct of_phandle_args *dma_spec,
 	if (dma_spec->args_count != 3)
 		return NULL;
 
-	fargs.req = be32_to_cpup(dma_spec->args+0);
-	fargs.src = be32_to_cpup(dma_spec->args+1);
-	fargs.dst = be32_to_cpup(dma_spec->args+2);
+	fargs.req = dma_spec->args[0];
+	fargs.src = dma_spec->args[1];
+	fargs.dst = dma_spec->args[2];
 
 	if (WARN_ON(fargs.req >= DW_DMA_MAX_NR_REQUESTS ||
 		    fargs.src >= dw->nr_masters ||
@@ -1289,9 +1275,49 @@ static struct dma_chan *dw_dma_xlate(struct of_phandle_args *dma_spec,
 	dma_cap_set(DMA_SLAVE, cap);
 
 	/* TODO: there should be a simpler way to do this */
-	return dma_request_channel(cap, dw_dma_generic_filter, &fargs);
+	return dma_request_channel(cap, dw_dma_of_filter, &fargs);
 }
 
+#ifdef CONFIG_ACPI
+static bool dw_dma_acpi_filter(struct dma_chan *chan, void *param)
+{
+	struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+	struct acpi_dma_spec *dma_spec = param;
+
+	if (chan->device->dev != dma_spec->dev ||
+	    chan->chan_id != dma_spec->chan_id)
+		return false;
+
+	dwc->request_line = dma_spec->slave_id;
+	dwc->src_master = dwc_get_sms(NULL);
+	dwc->dst_master = dwc_get_dms(NULL);
+
+	return true;
+}
+
+static void dw_dma_acpi_controller_register(struct dw_dma *dw)
+{
+	struct device *dev = dw->dma.dev;
+	struct acpi_dma_filter_info *info;
+	int ret;
+
+	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return;
+
+	dma_cap_zero(info->dma_cap);
+	dma_cap_set(DMA_SLAVE, info->dma_cap);
+	info->filter_fn = dw_dma_acpi_filter;
+
+	ret = devm_acpi_dma_controller_register(dev, acpi_dma_simple_xlate,
+						info);
+	if (ret)
+		dev_err(dev, "could not register acpi_dma_controller\n");
+}
+#else /* !CONFIG_ACPI */
+static inline void dw_dma_acpi_controller_register(struct dw_dma *dw) {}
+#endif /* !CONFIG_ACPI */
+
 /* --------------------- Cyclic DMA API extensions -------------------- */
 
 /**
@@ -1314,7 +1340,7 @@ int dw_dma_cyclic_start(struct dma_chan *chan)
 
 	spin_lock_irqsave(&dwc->lock, flags);
 
-	/* assert channel is idle */
+	/* Assert channel is idle */
 	if (dma_readl(dw, CH_EN) & dwc->mask) {
 		dev_err(chan2dev(&dwc->chan),
 			"BUG: Attempted to start non-idle channel\n");
@@ -1326,7 +1352,7 @@ int dw_dma_cyclic_start(struct dma_chan *chan)
 	dma_writel(dw, CLEAR.ERROR, dwc->mask);
 	dma_writel(dw, CLEAR.XFER, dwc->mask);
 
-	/* setup DMAC channel registers */
+	/* Setup DMAC channel registers */
 	channel_writel(dwc, LLP, dwc->cdesc->desc[0]->txd.phys);
 	channel_writel(dwc, CTL_LO, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN);
 	channel_writel(dwc, CTL_HI, 0);
@@ -1493,7 +1519,7 @@ struct dw_cyclic_desc *dw_dma_cyclic_prep(struct dma_chan *chan,
 		last = desc;
 	}
 
-	/* lets make a cyclic list */
+	/* Let's make a cyclic list */
 	last->lli.llp = cdesc->desc[0]->txd.phys;
 
 	dev_dbg(chan2dev(&dwc->chan), "cyclic prepared buf 0x%llx len %zu "
@@ -1697,7 +1723,7 @@ static int dw_probe(struct platform_device *pdev)
 
 	dw->regs = regs;
 
-	/* get hardware configuration parameters */
+	/* Get hardware configuration parameters */
 	if (autocfg) {
 		max_blk_size = dma_readl(dw, MAX_BLK_SIZE);
 
@@ -1714,10 +1740,10 @@ static int dw_probe(struct platform_device *pdev)
 	/* Calculate all channel mask before DMA setup */
 	dw->all_chan_mask = (1 << nr_channels) - 1;
 
-	/* force dma off, just in case */
+	/* Force dma off, just in case */
 	dw_dma_off(dw);
 
-	/* disable BLOCK interrupts as well */
+	/* Disable BLOCK interrupts as well */
 	channel_clear_bit(dw, MASK.BLOCK, dw->all_chan_mask);
 
 	err = devm_request_irq(&pdev->dev, irq, dw_dma_interrupt, 0,
@@ -1727,7 +1753,7 @@ static int dw_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, dw);
 
-	/* create a pool of consistent memory blocks for hardware descriptors */
+	/* Create a pool of consistent memory blocks for hardware descriptors */
 	dw->desc_pool = dmam_pool_create("dw_dmac_desc_pool", &pdev->dev,
 					 sizeof(struct dw_desc), 4, 0);
 	if (!dw->desc_pool) {
@@ -1767,8 +1793,9 @@ 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 */
+		/* Hardware configuration */
 		if (autocfg) {
 			unsigned int dwc_params;
 
@@ -1828,12 +1855,15 @@ static int dw_probe(struct platform_device *pdev)
 
 	if (pdev->dev.of_node) {
 		err = of_dma_controller_register(pdev->dev.of_node,
-						 dw_dma_xlate, dw);
-		if (err && err != -ENODEV)
+						 dw_dma_of_xlate, dw);
+		if (err)
 			dev_err(&pdev->dev,
 				"could not register of_dma_controller\n");
 	}
 
+	if (ACPI_HANDLE(&pdev->dev))
+		dw_dma_acpi_controller_register(dw);
+
 	return 0;
 }
 
@@ -1898,17 +1928,19 @@ static const struct dev_pm_ops dw_dev_pm_ops = {
 };
 
 #ifdef CONFIG_OF
-static const struct of_device_id dw_dma_id_table[] = {
+static const struct of_device_id dw_dma_of_id_table[] = {
 	{ .compatible = "snps,dma-spear1340" },
 	{}
 };
-MODULE_DEVICE_TABLE(of, dw_dma_id_table);
+MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
 #endif
 
-static const struct platform_device_id dw_dma_ids[] = {
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id dw_dma_acpi_id_table[] = {
 	{ "INTL9C60", 0 },
 	{ }
 };
+#endif
 
 static struct platform_driver dw_driver = {
 	.probe		= dw_probe,
@@ -1917,9 +1949,9 @@ static struct platform_driver dw_driver = {
 	.driver = {
 		.name	= "dw_dmac",
 		.pm	= &dw_dev_pm_ops,
-		.of_match_table = of_match_ptr(dw_dma_id_table),
+		.of_match_table = of_match_ptr(dw_dma_of_id_table),
+		.acpi_match_table = ACPI_PTR(dw_dma_acpi_id_table),
 	},
-	.id_table	= dw_dma_ids,
 };
 
 static int __init dw_init(void)