rapidio/tsi721: add DMA engine support

Adds support for DMA Engine API into Tsi721 mport driver.

Includes following changes for Tsi721 driver:
- Modifies BDMA register offset definitions to support per-channel handling
- Separates BDMA channel reserved for RIO Maintenance requests
- Adds DMA Engine callback routines

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Li Yang <leoli@freescale.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 134 insertions, 77 deletions

diff --git a/drivers/rapidio/devices/tsi721.c b/drivers/rapidio/devices/tsi721.c
index 30d2072..722246c 100644
--- a/drivers/rapidio/devices/tsi721.c
+++ b/drivers/rapidio/devices/tsi721.c
@@ -108,6 +108,7 @@ static int tsi721_maint_dma(struct tsi721_device *priv, u32 sys_size,
 			u16 destid, u8 hopcount, u32 offset, int len,
 			u32 *data, int do_wr)
 {
+	void __iomem *regs = priv->regs + TSI721_DMAC_BASE(priv->mdma.ch_id);
 	struct tsi721_dma_desc *bd_ptr;
 	u32 rd_count, swr_ptr, ch_stat;
 	int i, err = 0;
@@ -116,10 +117,9 @@ static int tsi721_maint_dma(struct tsi721_device *priv, u32 sys_size,
 	if (offset > (RIO_MAINT_SPACE_SZ - len) || (len != sizeof(u32)))
 		return -EINVAL;
 
-	bd_ptr = priv->bdma[TSI721_DMACH_MAINT].bd_base;
+	bd_ptr = priv->mdma.bd_base;
 
-	rd_count = ioread32(
-			priv->regs + TSI721_DMAC_DRDCNT(TSI721_DMACH_MAINT));
+	rd_count = ioread32(regs + TSI721_DMAC_DRDCNT);
 
 	/* Initialize DMA descriptor */
 	bd_ptr[0].type_id = cpu_to_le32((DTYPE2 << 29) | (op << 19) | destid);
@@ -134,19 +134,18 @@ static int tsi721_maint_dma(struct tsi721_device *priv, u32 sys_size,
 	mb();
 
 	/* Start DMA operation */
-	iowrite32(rd_count + 2,
-		priv->regs + TSI721_DMAC_DWRCNT(TSI721_DMACH_MAINT));
-	ioread32(priv->regs + TSI721_DMAC_DWRCNT(TSI721_DMACH_MAINT));
+	iowrite32(rd_count + 2,	regs + TSI721_DMAC_DWRCNT);
+	ioread32(regs + TSI721_DMAC_DWRCNT);
 	i = 0;
 
 	/* Wait until DMA transfer is finished */
-	while ((ch_stat = ioread32(priv->regs +
-		TSI721_DMAC_STS(TSI721_DMACH_MAINT))) & TSI721_DMAC_STS_RUN) {
+	while ((ch_stat = ioread32(regs + TSI721_DMAC_STS))
+							& TSI721_DMAC_STS_RUN) {
 		udelay(1);
 		if (++i >= 5000000) {
 			dev_dbg(&priv->pdev->dev,
 				"%s : DMA[%d] read timeout ch_status=%x\n",
-				__func__, TSI721_DMACH_MAINT, ch_stat);
+				__func__, priv->mdma.ch_id, ch_stat);
 			if (!do_wr)
 				*data = 0xffffffff;
 			err = -EIO;
@@ -162,13 +161,10 @@ static int tsi721_maint_dma(struct tsi721_device *priv, u32 sys_size,
 			__func__, ch_stat);
 		dev_dbg(&priv->pdev->dev, "OP=%d : destid=%x hc=%x off=%x\n",
 			do_wr ? MAINT_WR : MAINT_RD, destid, hopcount, offset);
-		iowrite32(TSI721_DMAC_INT_ALL,
-			priv->regs + TSI721_DMAC_INT(TSI721_DMACH_MAINT));
-		iowrite32(TSI721_DMAC_CTL_INIT,
-			priv->regs + TSI721_DMAC_CTL(TSI721_DMACH_MAINT));
+		iowrite32(TSI721_DMAC_INT_ALL, regs + TSI721_DMAC_INT);
+		iowrite32(TSI721_DMAC_CTL_INIT, regs + TSI721_DMAC_CTL);
 		udelay(10);
-		iowrite32(0, priv->regs +
-				TSI721_DMAC_DWRCNT(TSI721_DMACH_MAINT));
+		iowrite32(0, regs + TSI721_DMAC_DWRCNT);
 		udelay(1);
 		if (!do_wr)
 			*data = 0xffffffff;
@@ -184,8 +180,8 @@ static int tsi721_maint_dma(struct tsi721_device *priv, u32 sys_size,
 	 * NOTE: Skipping check and clear FIFO entries because we are waiting
 	 * for transfer to be completed.
 	 */
-	swr_ptr = ioread32(priv->regs + TSI721_DMAC_DSWP(TSI721_DMACH_MAINT));
-	iowrite32(swr_ptr, priv->regs + TSI721_DMAC_DSRP(TSI721_DMACH_MAINT));
+	swr_ptr = ioread32(regs + TSI721_DMAC_DSWP);
+	iowrite32(swr_ptr, regs + TSI721_DMAC_DSRP);
 err_out:
 
 	return err;
@@ -541,6 +537,22 @@ static irqreturn_t tsi721_irqhandler(int irq, void *ptr)
 			tsi721_pw_handler(mport);
 	}
 
+#ifdef CONFIG_RAPIDIO_DMA_ENGINE
+	if (dev_int & TSI721_DEV_INT_BDMA_CH) {
+		int ch;
+
+		if (dev_ch_int & TSI721_INT_BDMA_CHAN_M) {
+			dev_dbg(&priv->pdev->dev,
+				"IRQ from DMA channel 0x%08x\n", dev_ch_int);
+
+			for (ch = 0; ch < TSI721_DMA_MAXCH; ch++) {
+				if (!(dev_ch_int & TSI721_INT_BDMA_CHAN(ch)))
+					continue;
+				tsi721_bdma_handler(&priv->bdma[ch]);
+			}
+		}
+	}
+#endif
 	return IRQ_HANDLED;
 }
 
@@ -553,18 +565,26 @@ static void tsi721_interrupts_init(struct tsi721_device *priv)
 		priv->regs + TSI721_SR_CHINT(IDB_QUEUE));
 	iowrite32(TSI721_SR_CHINT_IDBQRCV,
 		priv->regs + TSI721_SR_CHINTE(IDB_QUEUE));
-	iowrite32(TSI721_INT_SR2PC_CHAN(IDB_QUEUE),
-		priv->regs + TSI721_DEV_CHAN_INTE);
 
 	/* Enable SRIO MAC interrupts */
 	iowrite32(TSI721_RIO_EM_DEV_INT_EN_INT,
 		priv->regs + TSI721_RIO_EM_DEV_INT_EN);
 
+	/* Enable interrupts from channels in use */
+#ifdef CONFIG_RAPIDIO_DMA_ENGINE
+	intr = TSI721_INT_SR2PC_CHAN(IDB_QUEUE) |
+		(TSI721_INT_BDMA_CHAN_M &
+		 ~TSI721_INT_BDMA_CHAN(TSI721_DMACH_MAINT));
+#else
+	intr = TSI721_INT_SR2PC_CHAN(IDB_QUEUE);
+#endif
+	iowrite32(intr,	priv->regs + TSI721_DEV_CHAN_INTE);
+
 	if (priv->flags & TSI721_USING_MSIX)
 		intr = TSI721_DEV_INT_SRIO;
 	else
 		intr = TSI721_DEV_INT_SR2PC_CH | TSI721_DEV_INT_SRIO |
-			TSI721_DEV_INT_SMSG_CH;
+			TSI721_DEV_INT_SMSG_CH | TSI721_DEV_INT_BDMA_CH;
 
 	iowrite32(intr, priv->regs + TSI721_DEV_INTE);
 	ioread32(priv->regs + TSI721_DEV_INTE);
@@ -715,12 +735,29 @@ static int tsi721_enable_msix(struct tsi721_device *priv)
 					TSI721_MSIX_OMSG_INT(i);
 	}
 
+#ifdef CONFIG_RAPIDIO_DMA_ENGINE
+	/*
+	 * Initialize MSI-X entries for Block DMA Engine:
+	 * this driver supports XXX DMA channels
+	 * (one is reserved for SRIO maintenance transactions)
+	 */
+	for (i = 0; i < TSI721_DMA_CHNUM; i++) {
+		entries[TSI721_VECT_DMA0_DONE + i].entry =
+					TSI721_MSIX_DMACH_DONE(i);
+		entries[TSI721_VECT_DMA0_INT + i].entry =
+					TSI721_MSIX_DMACH_INT(i);
+	}
+#endif /* CONFIG_RAPIDIO_DMA_ENGINE */
+
 	err = pci_enable_msix(priv->pdev, entries, ARRAY_SIZE(entries));
 	if (err) {
 		if (err > 0)
 			dev_info(&priv->pdev->dev,
 				 "Only %d MSI-X vectors available, "
 				 "not using MSI-X\n", err);
+		else
+			dev_err(&priv->pdev->dev,
+				"Failed to enable MSI-X (err=%d)\n", err);
 		return err;
 	}
 
@@ -760,6 +797,22 @@ static int tsi721_enable_msix(struct tsi721_device *priv)
 			 i, pci_name(priv->pdev));
 	}
 
+#ifdef CONFIG_RAPIDIO_DMA_ENGINE
+	for (i = 0; i < TSI721_DMA_CHNUM; i++) {
+		priv->msix[TSI721_VECT_DMA0_DONE + i].vector =
+				entries[TSI721_VECT_DMA0_DONE + i].vector;
+		snprintf(priv->msix[TSI721_VECT_DMA0_DONE + i].irq_name,
+			 IRQ_DEVICE_NAME_MAX, DRV_NAME "-dmad%d@pci:%s",
+			 i, pci_name(priv->pdev));
+
+		priv->msix[TSI721_VECT_DMA0_INT + i].vector =
+				entries[TSI721_VECT_DMA0_INT + i].vector;
+		snprintf(priv->msix[TSI721_VECT_DMA0_INT + i].irq_name,
+			 IRQ_DEVICE_NAME_MAX, DRV_NAME "-dmai%d@pci:%s",
+			 i, pci_name(priv->pdev));
+	}
+#endif /* CONFIG_RAPIDIO_DMA_ENGINE */
+
 	return 0;
 }
 #endif /* CONFIG_PCI_MSI */
@@ -888,20 +941,34 @@ static void tsi721_doorbell_free(struct tsi721_device *priv)
 	priv->idb_base = NULL;
 }
 
-static int tsi721_bdma_ch_init(struct tsi721_device *priv, int chnum)
+/**
+ * tsi721_bdma_maint_init - Initialize maintenance request BDMA channel.
+ * @priv: pointer to tsi721 private data
+ *
+ * Initialize BDMA channel allocated for RapidIO maintenance read/write
+ * request generation
+ * Returns %0 on success or %-ENOMEM on failure.
+ */
+static int tsi721_bdma_maint_init(struct tsi721_device *priv)
 {
 	struct tsi721_dma_desc *bd_ptr;
 	u64		*sts_ptr;
 	dma_addr_t	bd_phys, sts_phys;
 	int		sts_size;
-	int		bd_num = priv->bdma[chnum].bd_num;
+	int		bd_num = 2;
+	void __iomem	*regs;
 
-	dev_dbg(&priv->pdev->dev, "Init Block DMA Engine, CH%d\n", chnum);
+	dev_dbg(&priv->pdev->dev,
+		"Init Block DMA Engine for Maintenance requests, CH%d\n",
+		TSI721_DMACH_MAINT);
 
 	/*
 	 * Initialize DMA channel for maintenance requests
 	 */
 
+	priv->mdma.ch_id = TSI721_DMACH_MAINT;
+	regs = priv->regs + TSI721_DMAC_BASE(TSI721_DMACH_MAINT);
+
 	/* Allocate space for DMA descriptors */
 	bd_ptr = dma_zalloc_coherent(&priv->pdev->dev,
 					bd_num * sizeof(struct tsi721_dma_desc),
@@ -909,8 +976,9 @@ static int tsi721_bdma_ch_init(struct tsi721_device *priv, int chnum)
 	if (!bd_ptr)
 		return -ENOMEM;
 
-	priv->bdma[chnum].bd_phys = bd_phys;
-	priv->bdma[chnum].bd_base = bd_ptr;
+	priv->mdma.bd_num = bd_num;
+	priv->mdma.bd_phys = bd_phys;
+	priv->mdma.bd_base = bd_ptr;
 
 	dev_dbg(&priv->pdev->dev, "DMA descriptors @ %p (phys = %llx)\n",
 		bd_ptr, (unsigned long long)bd_phys);
@@ -927,13 +995,13 @@ static int tsi721_bdma_ch_init(struct tsi721_device *priv, int chnum)
 		dma_free_coherent(&priv->pdev->dev,
 				  bd_num * sizeof(struct tsi721_dma_desc),
 				  bd_ptr, bd_phys);
-		priv->bdma[chnum].bd_base = NULL;
+		priv->mdma.bd_base = NULL;
 		return -ENOMEM;
 	}
 
-	priv->bdma[chnum].sts_phys = sts_phys;
-	priv->bdma[chnum].sts_base = sts_ptr;
-	priv->bdma[chnum].sts_size = sts_size;
+	priv->mdma.sts_phys = sts_phys;
+	priv->mdma.sts_base = sts_ptr;
+	priv->mdma.sts_size = sts_size;
 
 	dev_dbg(&priv->pdev->dev,
 		"desc status FIFO @ %p (phys = %llx) size=0x%x\n",
@@ -946,83 +1014,61 @@ static int tsi721_bdma_ch_init(struct tsi721_device *priv, int chnum)
 	bd_ptr[bd_num - 1].next_hi = cpu_to_le32((u64)bd_phys >> 32);
 
 	/* Setup DMA descriptor pointers */
-	iowrite32(((u64)bd_phys >> 32),
-		priv->regs + TSI721_DMAC_DPTRH(chnum));
+	iowrite32(((u64)bd_phys >> 32),	regs + TSI721_DMAC_DPTRH);
 	iowrite32(((u64)bd_phys & TSI721_DMAC_DPTRL_MASK),
-		priv->regs + TSI721_DMAC_DPTRL(chnum));
+		regs + TSI721_DMAC_DPTRL);
 
 	/* Setup descriptor status FIFO */
-	iowrite32(((u64)sts_phys >> 32),
-		priv->regs + TSI721_DMAC_DSBH(chnum));
+	iowrite32(((u64)sts_phys >> 32), regs + TSI721_DMAC_DSBH);
 	iowrite32(((u64)sts_phys & TSI721_DMAC_DSBL_MASK),
-		priv->regs + TSI721_DMAC_DSBL(chnum));
+		regs + TSI721_DMAC_DSBL);
 	iowrite32(TSI721_DMAC_DSSZ_SIZE(sts_size),
-		priv->regs + TSI721_DMAC_DSSZ(chnum));
+		regs + TSI721_DMAC_DSSZ);
 
 	/* Clear interrupt bits */
-	iowrite32(TSI721_DMAC_INT_ALL,
-		priv->regs + TSI721_DMAC_INT(chnum));
+	iowrite32(TSI721_DMAC_INT_ALL, regs + TSI721_DMAC_INT);
 
-	ioread32(priv->regs + TSI721_DMAC_INT(chnum));
+	ioread32(regs + TSI721_DMAC_INT);
 
 	/* Toggle DMA channel initialization */
-	iowrite32(TSI721_DMAC_CTL_INIT,	priv->regs + TSI721_DMAC_CTL(chnum));
-	ioread32(priv->regs + TSI721_DMAC_CTL(chnum));
+	iowrite32(TSI721_DMAC_CTL_INIT,	regs + TSI721_DMAC_CTL);
+	ioread32(regs + TSI721_DMAC_CTL);
 	udelay(10);
 
 	return 0;
 }
 
-static int tsi721_bdma_ch_free(struct tsi721_device *priv, int chnum)
+static int tsi721_bdma_maint_free(struct tsi721_device *priv)
 {
 	u32 ch_stat;
+	struct tsi721_bdma_maint *mdma = &priv->mdma;
+	void __iomem *regs = priv->regs + TSI721_DMAC_BASE(mdma->ch_id);
 
-	if (priv->bdma[chnum].bd_base == NULL)
+	if (mdma->bd_base == NULL)
 		return 0;
 
 	/* Check if DMA channel still running */
-	ch_stat = ioread32(priv->regs +	TSI721_DMAC_STS(chnum));
+	ch_stat = ioread32(regs + TSI721_DMAC_STS);
 	if (ch_stat & TSI721_DMAC_STS_RUN)
 		return -EFAULT;
 
 	/* Put DMA channel into init state */
-	iowrite32(TSI721_DMAC_CTL_INIT,
-		priv->regs + TSI721_DMAC_CTL(chnum));
+	iowrite32(TSI721_DMAC_CTL_INIT,	regs + TSI721_DMAC_CTL);
 
 	/* Free space allocated for DMA descriptors */
 	dma_free_coherent(&priv->pdev->dev,
-		priv->bdma[chnum].bd_num * sizeof(struct tsi721_dma_desc),
-		priv->bdma[chnum].bd_base, priv->bdma[chnum].bd_phys);
-	priv->bdma[chnum].bd_base = NULL;
+		mdma->bd_num * sizeof(struct tsi721_dma_desc),
+		mdma->bd_base, mdma->bd_phys);
+	mdma->bd_base = NULL;
 
 	/* Free space allocated for status FIFO */
 	dma_free_coherent(&priv->pdev->dev,
-		priv->bdma[chnum].sts_size * sizeof(struct tsi721_dma_sts),
-		priv->bdma[chnum].sts_base, priv->bdma[chnum].sts_phys);
-	priv->bdma[chnum].sts_base = NULL;
-	return 0;
-}
-
-static int tsi721_bdma_init(struct tsi721_device *priv)
-{
-	/* Initialize BDMA channel allocated for RapidIO maintenance read/write
-	 * request generation
-	 */
-	priv->bdma[TSI721_DMACH_MAINT].bd_num = 2;
-	if (tsi721_bdma_ch_init(priv, TSI721_DMACH_MAINT)) {
-		dev_err(&priv->pdev->dev, "Unable to initialize maintenance DMA"
-			" channel %d, aborting\n", TSI721_DMACH_MAINT);
-		return -ENOMEM;
-	}
-
+		mdma->sts_size * sizeof(struct tsi721_dma_sts),
+		mdma->sts_base, mdma->sts_phys);
+	mdma->sts_base = NULL;
 	return 0;
 }
 
-static void tsi721_bdma_free(struct tsi721_device *priv)
-{
-	tsi721_bdma_ch_free(priv, TSI721_DMACH_MAINT);
-}
-
 /* Enable Inbound Messaging Interrupts */
 static void
 tsi721_imsg_interrupt_enable(struct tsi721_device *priv, int ch,
@@ -2035,7 +2081,8 @@ static void tsi721_disable_ints(struct tsi721_device *priv)
 
 	/* Disable all BDMA Channel interrupts */
 	for (ch = 0; ch < TSI721_DMA_MAXCH; ch++)
-		iowrite32(0, priv->regs + TSI721_DMAC_INTE(ch));
+		iowrite32(0,
+			priv->regs + TSI721_DMAC_BASE(ch) + TSI721_DMAC_INTE);
 
 	/* Disable all general BDMA interrupts */
 	iowrite32(0, priv->regs + TSI721_BDMA_INTE);
@@ -2104,6 +2151,7 @@ static int __devinit tsi721_setup_mport(struct tsi721_device *priv)
 	mport->phy_type = RIO_PHY_SERIAL;
 	mport->priv = (void *)priv;
 	mport->phys_efptr = 0x100;
+	priv->mport = mport;
 
 	INIT_LIST_HEAD(&mport->dbells);
 
@@ -2129,17 +2177,21 @@ static int __devinit tsi721_setup_mport(struct tsi721_device *priv)
 	if (!err) {
 		tsi721_interrupts_init(priv);
 		ops->pwenable = tsi721_pw_enable;
-	} else
+	} else {
 		dev_err(&pdev->dev, "Unable to get assigned PCI IRQ "
 			"vector %02X err=0x%x\n", pdev->irq, err);
+		goto err_exit;
+	}
 
+#ifdef CONFIG_RAPIDIO_DMA_ENGINE
+	tsi721_register_dma(priv);
+#endif
 	/* Enable SRIO link */
 	iowrite32(ioread32(priv->regs + TSI721_DEVCTL) |
 		  TSI721_DEVCTL_SRBOOT_CMPL,
 		  priv->regs + TSI721_DEVCTL);
 
 	rio_register_mport(mport);
-	priv->mport = mport;
 
 	if (mport->host_deviceid >= 0)
 		iowrite32(RIO_PORT_GEN_HOST | RIO_PORT_GEN_MASTER |
@@ -2149,6 +2201,11 @@ static int __devinit tsi721_setup_mport(struct tsi721_device *priv)
 		iowrite32(0, priv->regs + (0x100 + RIO_PORT_GEN_CTL_CSR));
 
 	return 0;
+
+err_exit:
+	kfree(mport);
+	kfree(ops);
+	return err;
 }
 
 static int __devinit tsi721_probe(struct pci_dev *pdev,
@@ -2294,7 +2351,7 @@ static int __devinit tsi721_probe(struct pci_dev *pdev,
 	tsi721_init_pc2sr_mapping(priv);
 	tsi721_init_sr2pc_mapping(priv);
 
-	if (tsi721_bdma_init(priv)) {
+	if (tsi721_bdma_maint_init(priv)) {
 		dev_err(&pdev->dev, "BDMA initialization failed, aborting\n");
 		err = -ENOMEM;
 		goto err_unmap_bars;
@@ -2319,7 +2376,7 @@ static int __devinit tsi721_probe(struct pci_dev *pdev,
 err_free_consistent:
 	tsi721_doorbell_free(priv);
 err_free_bdma:
-	tsi721_bdma_free(priv);
+	tsi721_bdma_maint_free(priv);
 err_unmap_bars:
 	if (priv->regs)
 		iounmap(priv->regs);