Message-ID: <1445565553-1141-1-git-send-email-yao.yuan@freescale.com>
Date:	Fri, 23 Oct 2015 09:59:11 +0800
From:	Yuan Yao <yao.yuan@...escale.com>
To:	<vinod.koul@...el.com>, <shawn.guo@...aro.org>
CC:	<dan.j.williams@...el.com>, <linux-kernel@...r.kernel.org>,
	<linux-arm-kernel@...ts.infradead.org>
Subject: [PATCH v2 1/3] dma: Add Freescale qDMA engine driver support

Add Freescale Queue Direct Memory Access(qDMA) controller support.
This module can be found on LS-1 and LS-2 SoCs.

This add the legacy mode support for qDMA.

Signed-off-by: Yuan Yao <yao.yuan@...escale.com>
---

 Changes since v1:
 1. Separate Binding.
 2. Remove dead code.
 3. Add depend on for QDMA.
---
 MAINTAINERS            |   8 +
 drivers/dma/Kconfig    |  11 ++
 drivers/dma/Makefile   |   1 +
 drivers/dma/fsl-qdma.c | 510 +++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 530 insertions(+)
 create mode 100644 drivers/dma/fsl-qdma.c

diff --git a/MAINTAINERS b/MAINTAINERS
index a2d50fe..bc504df 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4419,6 +4419,14 @@ L:	linuxppc-dev@...ts.ozlabs.org
 S:	Maintained
 F:	drivers/dma/fsldma.*
 
+FREESCALE qDMA DRIVER
+M:     Yuan Yao <yao.yuan@...escale.com>
+L:     linux-arm-kernel@...ts.infradead.org
+L:     dmaengine@...r.kernel.org
+S:     Maintained
+F:     Documentation/devicetree/bindings/dma/fsl-qdma.txt
+F:     drivers/dma/fsl-qdma.c
+
 FREESCALE I2C CPM DRIVER
 M:	Jochen Friedrich <jochen@...am.de>
 L:	linuxppc-dev@...ts.ozlabs.org
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index af81a7a..1743a89 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -193,6 +193,17 @@ config FSL_EDMA
 	  multiplexing capability for DMA request sources(slot).
 	  This module can be found on Freescale Vybrid and LS-1 SoCs.
 
+config FSL_QDMA
+	tristate "Freescale qDMA engine support"
+	depends on SOC_LS1021A || ARCH_LAYERSCAPE
+	select DMA_ENGINE
+	select DMA_VIRTUAL_CHANNELS
+	help
+	  Support the Freescale qDMA engine with command queue and legacy mode.
+	  Channel virtualization is supported through enqueuing of DMA jobs to,
+	  or dequeuing DMA jobs from, different work queues.
+	  This module can be found on Freescale LS SoCs.
+
 config FSL_RAID
         tristate "Freescale RAID engine Support"
         depends on FSL_SOC && !ASYNC_TX_ENABLE_CHANNEL_SWITCH
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index ef9c099..47d63fe 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_DW_DMAC_CORE) += dw/
 obj-$(CONFIG_EP93XX_DMA) += ep93xx_dma.o
 obj-$(CONFIG_FSL_DMA) += fsldma.o
 obj-$(CONFIG_FSL_EDMA) += fsl-edma.o
+obj-$(CONFIG_FSL_QDMA) += fsl-qdma.o
 obj-$(CONFIG_FSL_RAID) += fsl_raid.o
 obj-$(CONFIG_HSU_DMA) += hsu/
 obj-$(CONFIG_IMG_MDC_DMA) += img-mdc-dma.o
diff --git a/drivers/dma/fsl-qdma.c b/drivers/dma/fsl-qdma.c
new file mode 100644
index 0000000..b2c80d9
--- /dev/null
+++ b/drivers/dma/fsl-qdma.c
@@ -0,0 +1,510 @@
+/*
+ * drivers/dma/fsl-qdma.c
+ *
+ * Copyright 2014-2015 Freescale Semiconductor, Inc.
+ *
+ * Driver for the Freescale qDMA engine with legacy mode.
+ * This module can be found on Freescale LS SoCs.
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmapool.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_dma.h>
+#include <linux/of_irq.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include "virt-dma.h"
+
+#define FSL_QDMA_DMR		0x0
+#define FSL_QDMA_DSR_P		0x4
+
+#define FSL_QDMA_DSR_M		0x10004
+#define FSL_QDMA_DLMR		0x10100
+#define FSL_QDMA_DLSR		0x10104
+#define FSL_QDMA_DLSATR		0x10110
+#define FSL_QDMA_DLSAR		0x10114
+#define FSL_QDMA_DLDATR		0x10118
+#define FSL_QDMA_DLDAR		0x1011c
+#define FSL_QDMA_DLBCR		0x10120
+#define FSL_QDMA_DLESAD		0x10148
+#define FSL_QDMA_DLEDAD		0x1014c
+
+#define FSL_QDMA_DLMR_CS	0x1
+#define FSL_QDMA_DLMR_EOSIE	0x200
+#define FSL_QDMA_DLMR_EIE	0x40
+#define FSL_QDMA_DLSR_TE	0x80
+#define FSL_QDMA_DLSR_CH	0x20
+#define FSL_QDMA_DLSR_PE	0x10
+#define FSL_QDMA_DLSR_CB	0x4
+#define FSL_QDMA_DLSR_EOSI	0x2
+
+#define FSL_QDMA_SRTTYPE_R_N	0x40000
+
+struct fsl_qdma_tcd {
+	u64	saddr;
+	u32	nbytes;
+	u64	daddr;
+};
+
+struct fsl_qdma_chan_config {
+	enum dma_transfer_direction	dir;
+	enum dma_slave_buswidth		addr_width;
+	u32				burst;
+	u32				attr;
+};
+
+struct fsl_qdma_desc {
+	struct virt_dma_desc		vdesc;
+	struct fsl_qdma_chan		*qchan;
+	struct fsl_qdma_tcd		tcd;
+};
+
+struct fsl_qdma_chan {
+	struct virt_dma_chan		vchan;
+	struct fsl_qdma_desc		*desc;
+	enum dma_status			status;
+	u32				slave_id;
+	struct fsl_qdma_engine		*qdma;
+};
+
+struct fsl_qdma_engine {
+	struct dma_device	dma_dev;
+	void __iomem		*membase;
+	u32			n_chans;
+	struct mutex            fsl_qdma_mutex;
+	int			controller_irq;
+	int			err_irq;
+	bool			big_endian;
+	struct fsl_qdma_chan	chans[];
+
+};
+
+static u32 qdma_readl(struct fsl_qdma_engine *qdma, void __iomem *addr)
+{
+	if (qdma->big_endian)
+		return ioread32be(addr);
+	else
+		return ioread32(addr);
+}
+
+static void qdma_writel(struct fsl_qdma_engine *qdma, u32 val,
+						void __iomem *addr)
+{
+	if (qdma->big_endian)
+		iowrite32be(val, addr);
+	else
+		iowrite32(val, addr);
+}
+
+static struct fsl_qdma_chan *to_fsl_qdma_chan(struct dma_chan *chan)
+{
+	return container_of(chan, struct fsl_qdma_chan, vchan.chan);
+}
+
+static struct fsl_qdma_desc *to_fsl_qdma_desc(struct virt_dma_desc *vd)
+{
+	return container_of(vd, struct fsl_qdma_desc, vdesc);
+}
+
+static void fsl_qdma_free_chan_resources(struct dma_chan *chan)
+{
+	struct fsl_qdma_chan *fsl_chan = to_fsl_qdma_chan(chan);
+	unsigned long flags;
+	LIST_HEAD(head);
+
+	spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
+	vchan_get_all_descriptors(&fsl_chan->vchan, &head);
+	spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
+
+	vchan_dma_desc_free_list(&fsl_chan->vchan, &head);
+}
+
+static void fsl_qdma_set_tcd_params(struct fsl_qdma_chan *fsl_chan,
+					u64 src, u64 dst, u32 nbytes)
+{
+	void __iomem *addr = fsl_chan->qdma->membase;
+	u32 reg;
+
+	/*
+	 * Source address.
+	 * Represents address bits 31-0 of a 49-bit source address.
+	 */
+	qdma_writel(fsl_chan->qdma, (u32)src, addr + FSL_QDMA_DLSAR);
+	/*
+	 * Source address.
+	 * Represents address bits 47-32 of a 49-bit source address.
+	 */
+	reg = qdma_readl(fsl_chan->qdma, addr + FSL_QDMA_DLSATR);
+	reg |= (u16)(src >> 32) & 0xffff;
+	reg |= FSL_QDMA_SRTTYPE_R_N;
+	qdma_writel(fsl_chan->qdma, reg, addr + FSL_QDMA_DLSATR);
+	/*
+	 * Source address.
+	 * Represents address bits 48 of a 49-bit source address.
+	 */
+	reg = qdma_readl(fsl_chan->qdma, addr + FSL_QDMA_DLESAD);
+	reg |= (src >> 48) & 0x1;
+	qdma_writel(fsl_chan->qdma, reg, addr + FSL_QDMA_DLESAD);
+
+	/*
+	 * Destination address.
+	 * Represents address bits 31-0 of a 49-bit destination address.
+	 */
+	qdma_writel(fsl_chan->qdma, (u32)dst, addr + FSL_QDMA_DLDAR);
+	/*
+	 * Destination address.
+	 * Represents address bits 47-32 of a 49-bit destination address.
+	 */
+	reg = qdma_readl(fsl_chan->qdma, addr + FSL_QDMA_DLDATR);
+	reg |= (u16)(dst >> 32) & 0xffff;
+	reg |= FSL_QDMA_SRTTYPE_R_N;
+	qdma_writel(fsl_chan->qdma, reg, addr + FSL_QDMA_DLDATR);
+	/*
+	 * Destination address.
+	 * Represents address bits 48 of a 49-bit destination address.
+	 */
+	reg = qdma_readl(fsl_chan->qdma, addr + FSL_QDMA_DLEDAD);
+	reg |= (dst >> 48) & 0x1;
+	qdma_writel(fsl_chan->qdma, reg, addr + FSL_QDMA_DLEDAD);
+
+	/*
+	 * Byte count.
+	 * Contains the number of bytes to transfer.
+	 */
+	qdma_writel(fsl_chan->qdma, nbytes, addr + FSL_QDMA_DLBCR);
+}
+
+static int fsl_qdma_reg_init(struct fsl_qdma_engine *fsl_qdma)
+{
+	u32 reg;
+
+	reg = qdma_readl(fsl_qdma, fsl_qdma->membase + FSL_QDMA_DLMR);
+	reg |= FSL_QDMA_DLMR_EOSIE;
+	reg |= FSL_QDMA_DLMR_EIE;
+	qdma_writel(fsl_qdma, reg, fsl_qdma->membase + FSL_QDMA_DLMR);
+	return 0;
+}
+
+static void fsl_qdma_enable_request(struct fsl_qdma_chan *fsl_chan)
+{
+	void __iomem *addr = fsl_chan->qdma->membase;
+	u32 reg;
+
+	reg = qdma_readl(fsl_chan->qdma, addr + FSL_QDMA_DLMR);
+
+	reg &= ~FSL_QDMA_DLMR_CS;
+	qdma_writel(fsl_chan->qdma, reg, addr + FSL_QDMA_DLMR);
+
+	reg |= FSL_QDMA_DLMR_CS;
+	qdma_writel(fsl_chan->qdma, reg, addr + FSL_QDMA_DLMR);
+}
+
+static struct fsl_qdma_desc *fsl_qdma_alloc_desc(struct fsl_qdma_chan *fsl_chan)
+{
+	struct fsl_qdma_desc *fsl_desc;
+
+	fsl_desc = kzalloc(sizeof(*fsl_desc), GFP_NOWAIT);
+
+	if (!fsl_desc)
+		return NULL;
+
+	fsl_desc->qchan = fsl_chan;
+
+	return fsl_desc;
+}
+
+static void fsl_qdma_free_desc(struct virt_dma_desc *vdesc)
+{
+	struct fsl_qdma_desc *fsl_desc;
+
+	fsl_desc = to_fsl_qdma_desc(vdesc);
+	kfree(fsl_desc);
+}
+
+static void fsl_qdma_enqueue_desc(struct fsl_qdma_chan *fsl_chan)
+{
+	struct fsl_qdma_tcd *tcd;
+	struct virt_dma_desc *vdesc;
+
+	vdesc = vchan_next_desc(&fsl_chan->vchan);
+	if (!vdesc)
+		return;
+
+	fsl_chan->desc = to_fsl_qdma_desc(vdesc);
+	tcd = &fsl_chan->desc->tcd;
+	fsl_qdma_set_tcd_params(fsl_chan, tcd->saddr, tcd->daddr, tcd->nbytes);
+	fsl_qdma_enable_request(fsl_chan);
+	fsl_chan->status = DMA_IN_PROGRESS;
+}
+
+static void fsl_qdma_issue_pending(struct dma_chan *chan)
+{
+	struct fsl_qdma_chan *fsl_chan = to_fsl_qdma_chan(chan);
+	unsigned long flags;
+
+	spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
+
+	if (vchan_issue_pending(&fsl_chan->vchan) && !fsl_chan->desc)
+		fsl_qdma_enqueue_desc(fsl_chan);
+
+	spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
+}
+
+static struct dma_async_tx_descriptor *
+fsl_qdma_prep_memcpy(struct dma_chan *chan, dma_addr_t dst,
+		dma_addr_t src, size_t len, unsigned long flags)
+{
+	struct fsl_qdma_chan *fsl_chan = to_fsl_qdma_chan(chan);
+	struct fsl_qdma_desc *fsl_desc;
+	struct fsl_qdma_tcd *tcd;
+
+	fsl_desc = fsl_qdma_alloc_desc(fsl_chan);
+	if (!fsl_desc)
+		return NULL;
+
+	tcd = &fsl_desc->tcd;
+	tcd->saddr = (u64)src;
+	tcd->nbytes = (u32)len;
+	tcd->daddr = (u64)dst;
+
+	return vchan_tx_prep(&fsl_chan->vchan, &fsl_desc->vdesc, flags);
+}
+
+static enum dma_status fsl_qdma_tx_status(struct dma_chan *chan,
+		dma_cookie_t cookie, struct dma_tx_state *txstate)
+{
+	return dma_cookie_status(chan, cookie, txstate);
+}
+
+static irqreturn_t fsl_qdma_controller_handler(int irq, void *dev_id)
+{
+	struct fsl_qdma_engine *fsl_qdma = dev_id;
+	struct fsl_qdma_chan *fsl_chan = &fsl_qdma->chans[0];
+	void __iomem *addr = fsl_qdma->membase;
+	u32 reg;
+
+	reg = qdma_readl(fsl_qdma, addr + FSL_QDMA_DLSR);
+	if (!(reg & FSL_QDMA_DLSR_EOSI))
+		return IRQ_NONE;
+
+	/* Don't clean TE and PE bit if they are set. */
+	reg &= ~FSL_QDMA_DLSR_TE & ~FSL_QDMA_DLSR_PE;
+	qdma_writel(fsl_qdma, reg, addr + FSL_QDMA_DLSR);
+
+	spin_lock(&fsl_chan->vchan.lock);
+	list_del(&fsl_chan->desc->vdesc.node);
+	vchan_cookie_complete(&fsl_chan->desc->vdesc);
+	fsl_chan->desc = NULL;
+	fsl_chan->status = DMA_COMPLETE;
+	fsl_qdma_enqueue_desc(fsl_chan);
+	spin_unlock(&fsl_chan->vchan.lock);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t fsl_qdma_controller_handler_err(int irq, void *dev_id)
+{
+	struct fsl_qdma_engine *fsl_qdma = dev_id;
+	u32 reg;
+
+	reg = qdma_readl(fsl_qdma, fsl_qdma->membase + FSL_QDMA_DLSR);
+
+	if (reg & FSL_QDMA_DLSR_TE) {
+		dev_err(fsl_qdma->dma_dev.dev,
+			"Transfer error. Check your address please!\n");
+	}
+
+	if (reg & FSL_QDMA_DLSR_PE) {
+		dev_err(fsl_qdma->dma_dev.dev,
+			"Programming error. Check your setting please!\n");
+	}
+
+	/* Don't clean EOSI bit if it's set. */
+	reg &= ~FSL_QDMA_DLSR_EOSI;
+	qdma_writel(fsl_qdma, reg, fsl_qdma->membase + FSL_QDMA_DLSR);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t fsl_qdma_irq_handler(int irq, void *dev_id)
+{
+	if (fsl_qdma_controller_handler(irq, dev_id) == IRQ_HANDLED)
+		return IRQ_HANDLED;
+
+	return fsl_qdma_controller_handler_err(irq, dev_id);
+}
+
+static int fsl_qdma_irq_init(struct platform_device *pdev,
+					struct fsl_qdma_engine *fsl_qdma)
+{
+	int ret;
+
+	fsl_qdma->controller_irq = platform_get_irq_byname(pdev,
+							"qdma-tx");
+	if (fsl_qdma->controller_irq < 0) {
+		dev_err(&pdev->dev, "Can't get qdma controller irq.\n");
+		return fsl_qdma->controller_irq;
+	}
+
+	fsl_qdma->err_irq = platform_get_irq_byname(pdev,
+							"qdma-err");
+	if (fsl_qdma->err_irq < 0) {
+		dev_err(&pdev->dev, "Can't get qdma err irq.\n");
+		return fsl_qdma->err_irq;
+	}
+
+	if (fsl_qdma->controller_irq == fsl_qdma->err_irq) {
+		ret = devm_request_irq(&pdev->dev, fsl_qdma->controller_irq,
+					fsl_qdma_irq_handler, 0,
+					"qDMA controller", fsl_qdma);
+
+		if (ret) {
+			dev_err(&pdev->dev, "Can't register qDMA IRQ.\n");
+			return  ret;
+		}
+	} else {
+		ret = devm_request_irq(&pdev->dev, fsl_qdma->controller_irq,
+				fsl_qdma_controller_handler, 0,
+				"qDMA controller", fsl_qdma);
+		if (ret) {
+			dev_err(&pdev->dev,
+				"Can't register qDMA controller IRQ.\n");
+			return  ret;
+		}
+
+		ret = devm_request_irq(&pdev->dev, fsl_qdma->err_irq,
+				fsl_qdma_controller_handler_err, 0,
+				"qDMA err", fsl_qdma);
+		if (ret) {
+			dev_err(&pdev->dev, "Can't register qDMA err IRQ.\n");
+			return  ret;
+		}
+	}
+
+	return 0;
+}
+
+static int fsl_qdma_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct fsl_qdma_engine *fsl_qdma;
+	struct fsl_qdma_chan *fsl_chan;
+	struct resource *res;
+	unsigned int len, chans;
+	int ret, i;
+
+	ret = of_property_read_u32(np, "channels", &chans);
+	if (ret) {
+		dev_err(&pdev->dev, "Can't get channels.\n");
+		return ret;
+	}
+
+	len = sizeof(*fsl_qdma) + sizeof(*fsl_chan) * chans;
+	fsl_qdma = devm_kzalloc(&pdev->dev, len, GFP_KERNEL);
+	if (!fsl_qdma)
+		return -ENOMEM;
+
+	fsl_qdma->n_chans = chans;
+	mutex_init(&fsl_qdma->fsl_qdma_mutex);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	fsl_qdma->membase = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(fsl_qdma->membase))
+		return PTR_ERR(fsl_qdma->membase);
+
+	ret = fsl_qdma_irq_init(pdev, fsl_qdma);
+	if (ret)
+		return ret;
+
+	fsl_qdma->big_endian = of_property_read_bool(np, "big-endian");
+	INIT_LIST_HEAD(&fsl_qdma->dma_dev.channels);
+	for (i = 0; i < fsl_qdma->n_chans; i++) {
+		struct fsl_qdma_chan *fsl_chan = &fsl_qdma->chans[i];
+
+		fsl_chan->qdma = fsl_qdma;
+		fsl_chan->desc = NULL;
+		fsl_chan->vchan.desc_free = fsl_qdma_free_desc;
+		vchan_init(&fsl_chan->vchan, &fsl_qdma->dma_dev);
+	}
+
+	dma_cap_set(DMA_PRIVATE, fsl_qdma->dma_dev.cap_mask);
+	dma_cap_set(DMA_MEMCPY, fsl_qdma->dma_dev.cap_mask);
+
+	fsl_qdma->dma_dev.dev = &pdev->dev;
+	fsl_qdma->dma_dev.device_free_chan_resources
+		= fsl_qdma_free_chan_resources;
+	fsl_qdma->dma_dev.device_tx_status = fsl_qdma_tx_status;
+	fsl_qdma->dma_dev.device_prep_dma_memcpy = fsl_qdma_prep_memcpy;
+	fsl_qdma->dma_dev.device_issue_pending = fsl_qdma_issue_pending;
+
+	platform_set_drvdata(pdev, fsl_qdma);
+
+	ret = dma_async_device_register(&fsl_qdma->dma_dev);
+	if (ret) {
+		dev_err(&pdev->dev, "Can't register Freescale qDMA engine.\n");
+		return ret;
+	}
+
+	ret = fsl_qdma_reg_init(fsl_qdma);
+	if (ret) {
+		dev_err(&pdev->dev, "Can't Initialize the qDMA engine.\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int fsl_qdma_remove(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct fsl_qdma_engine *fsl_qdma = platform_get_drvdata(pdev);
+
+	of_dma_controller_free(np);
+	dma_async_device_unregister(&fsl_qdma->dma_dev);
+	return 0;
+}
+
+static const struct of_device_id fsl_qdma_dt_ids[] = {
+	{ .compatible = "fsl,ls1021a-qdma", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, fsl_qdma_dt_ids);
+
+static struct platform_driver fsl_qdma_driver = {
+	.driver		= {
+		.name	= "fsl-qdma",
+		.owner  = THIS_MODULE,
+		.of_match_table = fsl_qdma_dt_ids,
+	},
+	.probe          = fsl_qdma_probe,
+	.remove		= fsl_qdma_remove,
+};
+
+static int __init fsl_qdma_init(void)
+{
+	return platform_driver_register(&fsl_qdma_driver);
+}
+subsys_initcall(fsl_qdma_init);
+
+static void __exit fsl_qdma_exit(void)
+{
+	platform_driver_unregister(&fsl_qdma_driver);
+}
+module_exit(fsl_qdma_exit);
+
+MODULE_ALIAS("platform:fsl-qdma");
+MODULE_DESCRIPTION("Freescale qDMA engine driver");
+MODULE_LICENSE("GPL v2");
-- 
2.1.0.27.g96db324

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