1 files changed, 112 insertions, 62 deletions

diff --git a/drivers/dma/sf-pdma/sf-pdma.c b/drivers/dma/sf-pdma/sf-pdma.c
index 5c118c7e02bd..7ad3c29be146 100644
--- a/drivers/dma/sf-pdma/sf-pdma.c
+++ b/drivers/dma/sf-pdma/sf-pdma.c
@@ -20,9 +20,13 @@
 #include <linux/mod_devicetable.h>
 #include <linux/dma-mapping.h>
 #include <linux/of.h>
+#include <linux/of_dma.h>
+#include <linux/slab.h>
 
 #include "sf-pdma.h"
 
+#define PDMA_QUIRK_NO_STRICT_ORDERING   BIT(0)
+
 #ifndef readq
 static inline unsigned long long readq(void __iomem *addr)
 {
@@ -51,16 +55,6 @@ static inline struct sf_pdma_desc *to_sf_pdma_desc(struct virt_dma_desc *vd)
 static struct sf_pdma_desc *sf_pdma_alloc_desc(struct sf_pdma_chan *chan)
 {
 	struct sf_pdma_desc *desc;
-	unsigned long flags;
-
-	spin_lock_irqsave(&chan->lock, flags);
-
-	if (chan->desc && !chan->desc->in_use) {
-		spin_unlock_irqrestore(&chan->lock, flags);
-		return chan->desc;
-	}
-
-	spin_unlock_irqrestore(&chan->lock, flags);
 
 	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
 	if (!desc)
@@ -74,7 +68,7 @@ static struct sf_pdma_desc *sf_pdma_alloc_desc(struct sf_pdma_chan *chan)
 static void sf_pdma_fill_desc(struct sf_pdma_desc *desc,
 			      u64 dst, u64 src, u64 size)
 {
-	desc->xfer_type = PDMA_FULL_SPEED;
+	desc->xfer_type =  desc->chan->pdma->transfer_type;
 	desc->xfer_size = size;
 	desc->dst_addr = dst;
 	desc->src_addr = src;
@@ -93,6 +87,7 @@ sf_pdma_prep_dma_memcpy(struct dma_chan *dchan,	dma_addr_t dest, dma_addr_t src,
 {
 	struct sf_pdma_chan *chan = to_sf_pdma_chan(dchan);
 	struct sf_pdma_desc *desc;
+	unsigned long iflags;
 
 	if (chan && (!len || !dest || !src)) {
 		dev_err(chan->pdma->dma_dev.dev,
@@ -104,14 +99,12 @@ sf_pdma_prep_dma_memcpy(struct dma_chan *dchan,	dma_addr_t dest, dma_addr_t src,
 	if (!desc)
 		return NULL;
 
-	desc->in_use = true;
 	desc->dirn = DMA_MEM_TO_MEM;
 	desc->async_tx = vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
 
-	spin_lock_irqsave(&chan->vchan.lock, flags);
-	chan->desc = desc;
+	spin_lock_irqsave(&chan->vchan.lock, iflags);
 	sf_pdma_fill_desc(desc, dest, src, len);
-	spin_unlock_irqrestore(&chan->vchan.lock, flags);
+	spin_unlock_irqrestore(&chan->vchan.lock, iflags);
 
 	return desc->async_tx;
 }
@@ -168,11 +161,17 @@ static size_t sf_pdma_desc_residue(struct sf_pdma_chan *chan,
 	unsigned long flags;
 	u64 residue = 0;
 	struct sf_pdma_desc *desc;
-	struct dma_async_tx_descriptor *tx;
+	struct dma_async_tx_descriptor *tx = NULL;
 
 	spin_lock_irqsave(&chan->vchan.lock, flags);
 
-	tx = &chan->desc->vdesc.tx;
+	list_for_each_entry(vd, &chan->vchan.desc_submitted, node)
+		if (vd->tx.cookie == cookie)
+			tx = &vd->tx;
+
+	if (!tx)
+		goto out;
+
 	if (cookie == tx->chan->completed_cookie)
 		goto out;
 
@@ -239,6 +238,19 @@ static void sf_pdma_enable_request(struct sf_pdma_chan *chan)
 	writel(v, regs->ctrl);
 }
 
+static struct sf_pdma_desc *sf_pdma_get_first_pending_desc(struct sf_pdma_chan *chan)
+{
+	struct virt_dma_chan *vchan = &chan->vchan;
+	struct virt_dma_desc *vdesc;
+
+	if (list_empty(&vchan->desc_issued))
+		return NULL;
+
+	vdesc = list_first_entry(&vchan->desc_issued, struct virt_dma_desc, node);
+
+	return container_of(vdesc, struct sf_pdma_desc, vdesc);
+}
+
 static void sf_pdma_xfer_desc(struct sf_pdma_chan *chan)
 {
 	struct sf_pdma_desc *desc = chan->desc;
@@ -266,8 +278,11 @@ static void sf_pdma_issue_pending(struct dma_chan *dchan)
 
 	spin_lock_irqsave(&chan->vchan.lock, flags);
 
-	if (vchan_issue_pending(&chan->vchan) && chan->desc)
+	if (!chan->desc && vchan_issue_pending(&chan->vchan)) {
+		/* vchan_issue_pending has made a check that desc in not NULL */
+		chan->desc = sf_pdma_get_first_pending_desc(chan);
 		sf_pdma_xfer_desc(chan);
+	}
 
 	spin_unlock_irqrestore(&chan->vchan.lock, flags);
 }
@@ -277,13 +292,12 @@ static void sf_pdma_free_desc(struct virt_dma_desc *vdesc)
 	struct sf_pdma_desc *desc;
 
 	desc = to_sf_pdma_desc(vdesc);
-	desc->in_use = false;
+	kfree(desc);
 }
 
-static void sf_pdma_donebh_tasklet(unsigned long arg)
+static void sf_pdma_donebh_tasklet(struct tasklet_struct *t)
 {
-	struct sf_pdma_chan *chan = (struct sf_pdma_chan *)arg;
-	struct sf_pdma_desc *desc = chan->desc;
+	struct sf_pdma_chan *chan = from_tasklet(chan, t, done_tasklet);
 	unsigned long flags;
 
 	spin_lock_irqsave(&chan->lock, flags);
@@ -294,12 +308,20 @@ static void sf_pdma_donebh_tasklet(unsigned long arg)
 	}
 	spin_unlock_irqrestore(&chan->lock, flags);
 
-	dmaengine_desc_get_callback_invoke(desc->async_tx, NULL);
+	spin_lock_irqsave(&chan->vchan.lock, flags);
+	list_del(&chan->desc->vdesc.node);
+	vchan_cookie_complete(&chan->desc->vdesc);
+
+	chan->desc = sf_pdma_get_first_pending_desc(chan);
+	if (chan->desc)
+		sf_pdma_xfer_desc(chan);
+
+	spin_unlock_irqrestore(&chan->vchan.lock, flags);
 }
 
-static void sf_pdma_errbh_tasklet(unsigned long arg)
+static void sf_pdma_errbh_tasklet(struct tasklet_struct *t)
 {
-	struct sf_pdma_chan *chan = (struct sf_pdma_chan *)arg;
+	struct sf_pdma_chan *chan = from_tasklet(chan, t, err_tasklet);
 	struct sf_pdma_desc *desc = chan->desc;
 	unsigned long flags;
 
@@ -323,18 +345,16 @@ static irqreturn_t sf_pdma_done_isr(int irq, void *dev_id)
 {
 	struct sf_pdma_chan *chan = dev_id;
 	struct pdma_regs *regs = &chan->regs;
-	unsigned long flags;
 	u64 residue;
 
-	spin_lock_irqsave(&chan->vchan.lock, flags);
+	spin_lock(&chan->vchan.lock);
 	writel((readl(regs->ctrl)) & ~PDMA_DONE_STATUS_MASK, regs->ctrl);
 	residue = readq(regs->residue);
 
 	if (!residue) {
-		list_del(&chan->desc->vdesc.node);
-		vchan_cookie_complete(&chan->desc->vdesc);
+		tasklet_hi_schedule(&chan->done_tasklet);
 	} else {
-		/* submit next trascatioin if possible */
+		/* submit next transaction if possible */
 		struct sf_pdma_desc *desc = chan->desc;
 
 		desc->src_addr += desc->xfer_size - residue;
@@ -344,9 +364,7 @@ static irqreturn_t sf_pdma_done_isr(int irq, void *dev_id)
 		sf_pdma_xfer_desc(chan);
 	}
 
-	spin_unlock_irqrestore(&chan->vchan.lock, flags);
-
-	tasklet_hi_schedule(&chan->done_tasklet);
+	spin_unlock(&chan->vchan.lock);
 
 	return IRQ_HANDLED;
 }
@@ -355,11 +373,10 @@ static irqreturn_t sf_pdma_err_isr(int irq, void *dev_id)
 {
 	struct sf_pdma_chan *chan = dev_id;
 	struct pdma_regs *regs = &chan->regs;
-	unsigned long flags;
 
-	spin_lock_irqsave(&chan->lock, flags);
+	spin_lock(&chan->lock);
 	writel((readl(regs->ctrl)) & ~PDMA_ERR_STATUS_MASK, regs->ctrl);
-	spin_unlock_irqrestore(&chan->lock, flags);
+	spin_unlock(&chan->lock);
 
 	tasklet_schedule(&chan->err_tasklet);
 
@@ -390,10 +407,8 @@ static int sf_pdma_irq_init(struct platform_device *pdev, struct sf_pdma *pdma)
 		chan = &pdma->chans[i];
 
 		irq = platform_get_irq(pdev, i * 2);
-		if (irq < 0) {
-			dev_err(&pdev->dev, "ch(%d) Can't get done irq.\n", i);
+		if (irq < 0)
 			return -EINVAL;
-		}
 
 		r = devm_request_irq(&pdev->dev, irq, sf_pdma_done_isr, 0,
 				     dev_name(&pdev->dev), (void *)chan);
@@ -405,10 +420,8 @@ static int sf_pdma_irq_init(struct platform_device *pdev, struct sf_pdma *pdma)
 		chan->txirq = irq;
 
 		irq = platform_get_irq(pdev, (i * 2) + 1);
-		if (irq < 0) {
-			dev_err(&pdev->dev, "ch(%d) Can't get err irq.\n", i);
+		if (irq < 0)
 			return -EINVAL;
-		}
 
 		r = devm_request_irq(&pdev->dev, irq, sf_pdma_err_isr, 0,
 				     dev_name(&pdev->dev), (void *)chan);
@@ -475,36 +488,48 @@ static void sf_pdma_setup_chans(struct sf_pdma *pdma)
 
 		writel(PDMA_CLEAR_CTRL, chan->regs.ctrl);
 
-		tasklet_init(&chan->done_tasklet,
-			     sf_pdma_donebh_tasklet, (unsigned long)chan);
-		tasklet_init(&chan->err_tasklet,
-			     sf_pdma_errbh_tasklet, (unsigned long)chan);
+		tasklet_setup(&chan->done_tasklet, sf_pdma_donebh_tasklet);
+		tasklet_setup(&chan->err_tasklet, sf_pdma_errbh_tasklet);
 	}
 }
 
 static int sf_pdma_probe(struct platform_device *pdev)
 {
+	const struct sf_pdma_driver_platdata *ddata;
 	struct sf_pdma *pdma;
-	struct sf_pdma_chan *chan;
-	struct resource *res;
-	int len, chans;
-	int ret;
+	int ret, n_chans;
 	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 |
 		DMA_SLAVE_BUSWIDTH_64_BYTES;
 
-	chans = PDMA_NR_CH;
-	len = sizeof(*pdma) + sizeof(*chan) * chans;
-	pdma = devm_kzalloc(&pdev->dev, len, GFP_KERNEL);
+	ret = of_property_read_u32(pdev->dev.of_node, "dma-channels", &n_chans);
+	if (ret) {
+		/* backwards-compatibility for no dma-channels property */
+		dev_dbg(&pdev->dev, "set number of channels to default value: 4\n");
+		n_chans = PDMA_MAX_NR_CH;
+	} else if (n_chans > PDMA_MAX_NR_CH) {
+		dev_err(&pdev->dev, "the number of channels exceeds the maximum\n");
+		return -EINVAL;
+	}
+
+	pdma = devm_kzalloc(&pdev->dev, struct_size(pdma, chans, n_chans),
+			    GFP_KERNEL);
 	if (!pdma)
 		return -ENOMEM;
 
-	pdma->n_chans = chans;
+	pdma->n_chans = n_chans;
+
+	pdma->transfer_type = PDMA_FULL_SPEED | PDMA_STRICT_ORDERING;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	pdma->membase = devm_ioremap_resource(&pdev->dev, res);
+	ddata  = device_get_match_data(&pdev->dev);
+	if (ddata) {
+		if (ddata->quirks & PDMA_QUIRK_NO_STRICT_ORDERING)
+			pdma->transfer_type &= ~PDMA_STRICT_ORDERING;
+	}
+
+	pdma->membase = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(pdma->membase))
 		return PTR_ERR(pdma->membase);
 
@@ -550,16 +575,29 @@ static int sf_pdma_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	ret = of_dma_controller_register(pdev->dev.of_node,
+					 of_dma_xlate_by_chan_id, pdma);
+	if (ret < 0) {
+		dev_err(&pdev->dev,
+			"Can't register SiFive Platform OF_DMA. (%d)\n", ret);
+		goto err_unregister;
+	}
+
 	return 0;
+
+err_unregister:
+	dma_async_device_unregister(&pdma->dma_dev);
+
+	return ret;
 }
 
-static int sf_pdma_remove(struct platform_device *pdev)
+static void sf_pdma_remove(struct platform_device *pdev)
 {
 	struct sf_pdma *pdma = platform_get_drvdata(pdev);
 	struct sf_pdma_chan *ch;
 	int i;
 
-	for (i = 0; i < PDMA_NR_CH; i++) {
+	for (i = 0; i < pdma->n_chans; i++) {
 		ch = &pdma->chans[i];
 
 		devm_free_irq(&pdev->dev, ch->txirq, ch);
@@ -570,13 +608,25 @@ static int sf_pdma_remove(struct platform_device *pdev)
 		tasklet_kill(&ch->err_tasklet);
 	}
 
-	dma_async_device_unregister(&pdma->dma_dev);
+	if (pdev->dev.of_node)
+		of_dma_controller_free(pdev->dev.of_node);
 
-	return 0;
+	dma_async_device_unregister(&pdma->dma_dev);
 }
 
+static const struct sf_pdma_driver_platdata mpfs_pdma = {
+	.quirks = PDMA_QUIRK_NO_STRICT_ORDERING,
+};
+
 static const struct of_device_id sf_pdma_dt_ids[] = {
-	{ .compatible = "sifive,fu540-c000-pdma" },
+	{
+		.compatible = "sifive,fu540-c000-pdma",
+	}, {
+		.compatible = "sifive,pdma0",
+	}, {
+		.compatible = "microchip,mpfs-pdma",
+		.data	    = &mpfs_pdma,
+	},
 	{},
 };
 MODULE_DEVICE_TABLE(of, sf_pdma_dt_ids);
@@ -586,7 +636,7 @@ static struct platform_driver sf_pdma_driver = {
 	.remove		= sf_pdma_remove,
 	.driver		= {
 		.name	= "sf-pdma",
-		.of_match_table = of_match_ptr(sf_pdma_dt_ids),
+		.of_match_table = sf_pdma_dt_ids,
 	},
 };