1 files changed, 519 insertions, 0 deletions

diff --git a/drivers/dma/fsl-edma.c b/drivers/dma/fsl-edma.c
new file mode 100644
index 000000000..76cbf54ae
--- /dev/null
+++ b/drivers/dma/fsl-edma.c
@@ -0,0 +1,519 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * drivers/dma/fsl-edma.c
+ *
+ * Copyright 2013-2014 Freescale Semiconductor, Inc.
+ *
+ * Driver for the Freescale eDMA engine with flexible channel multiplexing
+ * capability for DMA request sources. The eDMA block can be found on some
+ * Vybrid and Layerscape SoCs.
+ */
+
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_dma.h>
+#include <linux/dma-mapping.h>
+
+#include "fsl-edma-common.h"
+
+static void fsl_edma_synchronize(struct dma_chan *chan)
+{
+	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
+
+	vchan_synchronize(&fsl_chan->vchan);
+}
+
+static irqreturn_t fsl_edma_tx_handler(int irq, void *dev_id)
+{
+	struct fsl_edma_engine *fsl_edma = dev_id;
+	unsigned int intr, ch;
+	struct edma_regs *regs = &fsl_edma->regs;
+	struct fsl_edma_chan *fsl_chan;
+
+	intr = edma_readl(fsl_edma, regs->intl);
+	if (!intr)
+		return IRQ_NONE;
+
+	for (ch = 0; ch < fsl_edma->n_chans; ch++) {
+		if (intr & (0x1 << ch)) {
+			edma_writeb(fsl_edma, EDMA_CINT_CINT(ch), regs->cint);
+
+			fsl_chan = &fsl_edma->chans[ch];
+
+			spin_lock(&fsl_chan->vchan.lock);
+
+			if (!fsl_chan->edesc) {
+				/* terminate_all called before */
+				spin_unlock(&fsl_chan->vchan.lock);
+				continue;
+			}
+
+			if (!fsl_chan->edesc->iscyclic) {
+				list_del(&fsl_chan->edesc->vdesc.node);
+				vchan_cookie_complete(&fsl_chan->edesc->vdesc);
+				fsl_chan->edesc = NULL;
+				fsl_chan->status = DMA_COMPLETE;
+				fsl_chan->idle = true;
+			} else {
+				vchan_cyclic_callback(&fsl_chan->edesc->vdesc);
+			}
+
+			if (!fsl_chan->edesc)
+				fsl_edma_xfer_desc(fsl_chan);
+
+			spin_unlock(&fsl_chan->vchan.lock);
+		}
+	}
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t fsl_edma_err_handler(int irq, void *dev_id)
+{
+	struct fsl_edma_engine *fsl_edma = dev_id;
+	unsigned int err, ch;
+	struct edma_regs *regs = &fsl_edma->regs;
+
+	err = edma_readl(fsl_edma, regs->errl);
+	if (!err)
+		return IRQ_NONE;
+
+	for (ch = 0; ch < fsl_edma->n_chans; ch++) {
+		if (err & (0x1 << ch)) {
+			fsl_edma_disable_request(&fsl_edma->chans[ch]);
+			edma_writeb(fsl_edma, EDMA_CERR_CERR(ch), regs->cerr);
+			fsl_edma->chans[ch].status = DMA_ERROR;
+			fsl_edma->chans[ch].idle = true;
+		}
+	}
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t fsl_edma_irq_handler(int irq, void *dev_id)
+{
+	if (fsl_edma_tx_handler(irq, dev_id) == IRQ_HANDLED)
+		return IRQ_HANDLED;
+
+	return fsl_edma_err_handler(irq, dev_id);
+}
+
+static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
+		struct of_dma *ofdma)
+{
+	struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data;
+	struct dma_chan *chan, *_chan;
+	struct fsl_edma_chan *fsl_chan;
+	u32 dmamux_nr = fsl_edma->drvdata->dmamuxs;
+	unsigned long chans_per_mux = fsl_edma->n_chans / dmamux_nr;
+
+	if (dma_spec->args_count != 2)
+		return NULL;
+
+	mutex_lock(&fsl_edma->fsl_edma_mutex);
+	list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels, device_node) {
+		if (chan->client_count)
+			continue;
+		if ((chan->chan_id / chans_per_mux) == dma_spec->args[0]) {
+			chan = dma_get_slave_channel(chan);
+			if (chan) {
+				chan->device->privatecnt++;
+				fsl_chan = to_fsl_edma_chan(chan);
+				fsl_chan->slave_id = dma_spec->args[1];
+				fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id,
+						true);
+				mutex_unlock(&fsl_edma->fsl_edma_mutex);
+				return chan;
+			}
+		}
+	}
+	mutex_unlock(&fsl_edma->fsl_edma_mutex);
+	return NULL;
+}
+
+static int
+fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
+{
+	int ret;
+
+	fsl_edma->txirq = platform_get_irq_byname(pdev, "edma-tx");
+	if (fsl_edma->txirq < 0)
+		return fsl_edma->txirq;
+
+	fsl_edma->errirq = platform_get_irq_byname(pdev, "edma-err");
+	if (fsl_edma->errirq < 0)
+		return fsl_edma->errirq;
+
+	if (fsl_edma->txirq == fsl_edma->errirq) {
+		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
+				fsl_edma_irq_handler, 0, "eDMA", fsl_edma);
+		if (ret) {
+			dev_err(&pdev->dev, "Can't register eDMA IRQ.\n");
+			return ret;
+		}
+	} else {
+		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
+				fsl_edma_tx_handler, 0, "eDMA tx", fsl_edma);
+		if (ret) {
+			dev_err(&pdev->dev, "Can't register eDMA tx IRQ.\n");
+			return ret;
+		}
+
+		ret = devm_request_irq(&pdev->dev, fsl_edma->errirq,
+				fsl_edma_err_handler, 0, "eDMA err", fsl_edma);
+		if (ret) {
+			dev_err(&pdev->dev, "Can't register eDMA err IRQ.\n");
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int
+fsl_edma2_irq_init(struct platform_device *pdev,
+		   struct fsl_edma_engine *fsl_edma)
+{
+	int i, ret, irq;
+	int count;
+
+	count = platform_irq_count(pdev);
+	dev_dbg(&pdev->dev, "%s Found %d interrupts\r\n", __func__, count);
+	if (count <= 2) {
+		dev_err(&pdev->dev, "Interrupts in DTS not correct.\n");
+		return -EINVAL;
+	}
+	/*
+	 * 16 channel independent interrupts + 1 error interrupt on i.mx7ulp.
+	 * 2 channel share one interrupt, for example, ch0/ch16, ch1/ch17...
+	 * For now, just simply request irq without IRQF_SHARED flag, since 16
+	 * channels are enough on i.mx7ulp whose M4 domain own some peripherals.
+	 */
+	for (i = 0; i < count; i++) {
+		irq = platform_get_irq(pdev, i);
+		if (irq < 0)
+			return -ENXIO;
+
+		sprintf(fsl_edma->chans[i].chan_name, "eDMA2-CH%02d", i);
+
+		/* The last IRQ is for eDMA err */
+		if (i == count - 1)
+			ret = devm_request_irq(&pdev->dev, irq,
+						fsl_edma_err_handler,
+						0, "eDMA2-ERR", fsl_edma);
+		else
+			ret = devm_request_irq(&pdev->dev, irq,
+						fsl_edma_tx_handler, 0,
+						fsl_edma->chans[i].chan_name,
+						fsl_edma);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static void fsl_edma_irq_exit(
+		struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
+{
+	if (fsl_edma->txirq == fsl_edma->errirq) {
+		devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
+	} else {
+		devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
+		devm_free_irq(&pdev->dev, fsl_edma->errirq, fsl_edma);
+	}
+}
+
+static void fsl_disable_clocks(struct fsl_edma_engine *fsl_edma, int nr_clocks)
+{
+	int i;
+
+	for (i = 0; i < nr_clocks; i++)
+		clk_disable_unprepare(fsl_edma->muxclk[i]);
+}
+
+static struct fsl_edma_drvdata vf610_data = {
+	.version = v1,
+	.dmamuxs = DMAMUX_NR,
+	.setup_irq = fsl_edma_irq_init,
+};
+
+static struct fsl_edma_drvdata ls1028a_data = {
+	.version = v1,
+	.dmamuxs = DMAMUX_NR,
+	.mux_swap = true,
+	.setup_irq = fsl_edma_irq_init,
+};
+
+static struct fsl_edma_drvdata imx7ulp_data = {
+	.version = v3,
+	.dmamuxs = 1,
+	.has_dmaclk = true,
+	.setup_irq = fsl_edma2_irq_init,
+};
+
+static const struct of_device_id fsl_edma_dt_ids[] = {
+	{ .compatible = "fsl,vf610-edma", .data = &vf610_data},
+	{ .compatible = "fsl,ls1028a-edma", .data = &ls1028a_data},
+	{ .compatible = "fsl,imx7ulp-edma", .data = &imx7ulp_data},
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, fsl_edma_dt_ids);
+
+static int fsl_edma_probe(struct platform_device *pdev)
+{
+	const struct of_device_id *of_id =
+			of_match_device(fsl_edma_dt_ids, &pdev->dev);
+	struct device_node *np = pdev->dev.of_node;
+	struct fsl_edma_engine *fsl_edma;
+	const struct fsl_edma_drvdata *drvdata = NULL;
+	struct fsl_edma_chan *fsl_chan;
+	struct edma_regs *regs;
+	struct resource *res;
+	int len, chans;
+	int ret, i;
+
+	if (of_id)
+		drvdata = of_id->data;
+	if (!drvdata) {
+		dev_err(&pdev->dev, "unable to find driver data\n");
+		return -EINVAL;
+	}
+
+	ret = of_property_read_u32(np, "dma-channels", &chans);
+	if (ret) {
+		dev_err(&pdev->dev, "Can't get dma-channels.\n");
+		return ret;
+	}
+
+	len = sizeof(*fsl_edma) + sizeof(*fsl_chan) * chans;
+	fsl_edma = devm_kzalloc(&pdev->dev, len, GFP_KERNEL);
+	if (!fsl_edma)
+		return -ENOMEM;
+
+	fsl_edma->drvdata = drvdata;
+	fsl_edma->n_chans = chans;
+	mutex_init(&fsl_edma->fsl_edma_mutex);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	fsl_edma->membase = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(fsl_edma->membase))
+		return PTR_ERR(fsl_edma->membase);
+
+	fsl_edma_setup_regs(fsl_edma);
+	regs = &fsl_edma->regs;
+
+	if (drvdata->has_dmaclk) {
+		fsl_edma->dmaclk = devm_clk_get(&pdev->dev, "dma");
+		if (IS_ERR(fsl_edma->dmaclk)) {
+			dev_err(&pdev->dev, "Missing DMA block clock.\n");
+			return PTR_ERR(fsl_edma->dmaclk);
+		}
+
+		ret = clk_prepare_enable(fsl_edma->dmaclk);
+		if (ret) {
+			dev_err(&pdev->dev, "DMA clk block failed.\n");
+			return ret;
+		}
+	}
+
+	for (i = 0; i < fsl_edma->drvdata->dmamuxs; i++) {
+		char clkname[32];
+
+		res = platform_get_resource(pdev, IORESOURCE_MEM, 1 + i);
+		fsl_edma->muxbase[i] = devm_ioremap_resource(&pdev->dev, res);
+		if (IS_ERR(fsl_edma->muxbase[i])) {
+			/* on error: disable all previously enabled clks */
+			fsl_disable_clocks(fsl_edma, i);
+			return PTR_ERR(fsl_edma->muxbase[i]);
+		}
+
+		sprintf(clkname, "dmamux%d", i);
+		fsl_edma->muxclk[i] = devm_clk_get(&pdev->dev, clkname);
+		if (IS_ERR(fsl_edma->muxclk[i])) {
+			dev_err(&pdev->dev, "Missing DMAMUX block clock.\n");
+			/* on error: disable all previously enabled clks */
+			fsl_disable_clocks(fsl_edma, i);
+			return PTR_ERR(fsl_edma->muxclk[i]);
+		}
+
+		ret = clk_prepare_enable(fsl_edma->muxclk[i]);
+		if (ret)
+			/* on error: disable all previously enabled clks */
+			fsl_disable_clocks(fsl_edma, i);
+
+	}
+
+	fsl_edma->big_endian = of_property_read_bool(np, "big-endian");
+
+	INIT_LIST_HEAD(&fsl_edma->dma_dev.channels);
+	for (i = 0; i < fsl_edma->n_chans; i++) {
+		struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i];
+
+		fsl_chan->edma = fsl_edma;
+		fsl_chan->pm_state = RUNNING;
+		fsl_chan->slave_id = 0;
+		fsl_chan->idle = true;
+		fsl_chan->dma_dir = DMA_NONE;
+		fsl_chan->vchan.desc_free = fsl_edma_free_desc;
+		vchan_init(&fsl_chan->vchan, &fsl_edma->dma_dev);
+
+		edma_writew(fsl_edma, 0x0, &regs->tcd[i].csr);
+		fsl_edma_chan_mux(fsl_chan, 0, false);
+	}
+
+	edma_writel(fsl_edma, ~0, regs->intl);
+	ret = fsl_edma->drvdata->setup_irq(pdev, fsl_edma);
+	if (ret)
+		return ret;
+
+	dma_cap_set(DMA_PRIVATE, fsl_edma->dma_dev.cap_mask);
+	dma_cap_set(DMA_SLAVE, fsl_edma->dma_dev.cap_mask);
+	dma_cap_set(DMA_CYCLIC, fsl_edma->dma_dev.cap_mask);
+	dma_cap_set(DMA_MEMCPY, fsl_edma->dma_dev.cap_mask);
+
+	fsl_edma->dma_dev.dev = &pdev->dev;
+	fsl_edma->dma_dev.device_alloc_chan_resources
+		= fsl_edma_alloc_chan_resources;
+	fsl_edma->dma_dev.device_free_chan_resources
+		= fsl_edma_free_chan_resources;
+	fsl_edma->dma_dev.device_tx_status = fsl_edma_tx_status;
+	fsl_edma->dma_dev.device_prep_slave_sg = fsl_edma_prep_slave_sg;
+	fsl_edma->dma_dev.device_prep_dma_cyclic = fsl_edma_prep_dma_cyclic;
+	fsl_edma->dma_dev.device_prep_dma_memcpy = fsl_edma_prep_memcpy;
+	fsl_edma->dma_dev.device_config = fsl_edma_slave_config;
+	fsl_edma->dma_dev.device_pause = fsl_edma_pause;
+	fsl_edma->dma_dev.device_resume = fsl_edma_resume;
+	fsl_edma->dma_dev.device_terminate_all = fsl_edma_terminate_all;
+	fsl_edma->dma_dev.device_synchronize = fsl_edma_synchronize;
+	fsl_edma->dma_dev.device_issue_pending = fsl_edma_issue_pending;
+
+	fsl_edma->dma_dev.src_addr_widths = FSL_EDMA_BUSWIDTHS;
+	fsl_edma->dma_dev.dst_addr_widths = FSL_EDMA_BUSWIDTHS;
+	fsl_edma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
+
+	fsl_edma->dma_dev.copy_align = DMAENGINE_ALIGN_32_BYTES;
+	/* Per worst case 'nbytes = 1' take CITER as the max_seg_size */
+	dma_set_max_seg_size(fsl_edma->dma_dev.dev, 0x3fff);
+
+	platform_set_drvdata(pdev, fsl_edma);
+
+	ret = dma_async_device_register(&fsl_edma->dma_dev);
+	if (ret) {
+		dev_err(&pdev->dev,
+			"Can't register Freescale eDMA engine. (%d)\n", ret);
+		fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs);
+		return ret;
+	}
+
+	ret = of_dma_controller_register(np, fsl_edma_xlate, fsl_edma);
+	if (ret) {
+		dev_err(&pdev->dev,
+			"Can't register Freescale eDMA of_dma. (%d)\n", ret);
+		dma_async_device_unregister(&fsl_edma->dma_dev);
+		fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs);
+		return ret;
+	}
+
+	/* enable round robin arbitration */
+	edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
+
+	return 0;
+}
+
+static int fsl_edma_remove(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct fsl_edma_engine *fsl_edma = platform_get_drvdata(pdev);
+
+	fsl_edma_irq_exit(pdev, fsl_edma);
+	fsl_edma_cleanup_vchan(&fsl_edma->dma_dev);
+	of_dma_controller_free(np);
+	dma_async_device_unregister(&fsl_edma->dma_dev);
+	fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs);
+
+	return 0;
+}
+
+static int fsl_edma_suspend_late(struct device *dev)
+{
+	struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
+	struct fsl_edma_chan *fsl_chan;
+	unsigned long flags;
+	int i;
+
+	for (i = 0; i < fsl_edma->n_chans; i++) {
+		fsl_chan = &fsl_edma->chans[i];
+		spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
+		/* Make sure chan is idle or will force disable. */
+		if (unlikely(!fsl_chan->idle)) {
+			dev_warn(dev, "WARN: There is non-idle channel.");
+			fsl_edma_disable_request(fsl_chan);
+			fsl_edma_chan_mux(fsl_chan, 0, false);
+		}
+
+		fsl_chan->pm_state = SUSPENDED;
+		spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
+	}
+
+	return 0;
+}
+
+static int fsl_edma_resume_early(struct device *dev)
+{
+	struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
+	struct fsl_edma_chan *fsl_chan;
+	struct edma_regs *regs = &fsl_edma->regs;
+	int i;
+
+	for (i = 0; i < fsl_edma->n_chans; i++) {
+		fsl_chan = &fsl_edma->chans[i];
+		fsl_chan->pm_state = RUNNING;
+		edma_writew(fsl_edma, 0x0, &regs->tcd[i].csr);
+		if (fsl_chan->slave_id != 0)
+			fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id, true);
+	}
+
+	edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
+
+	return 0;
+}
+
+/*
+ * eDMA provides the service to others, so it should be suspend late
+ * and resume early. When eDMA suspend, all of the clients should stop
+ * the DMA data transmission and let the channel idle.
+ */
+static const struct dev_pm_ops fsl_edma_pm_ops = {
+	.suspend_late   = fsl_edma_suspend_late,
+	.resume_early   = fsl_edma_resume_early,
+};
+
+static struct platform_driver fsl_edma_driver = {
+	.driver		= {
+		.name	= "fsl-edma",
+		.of_match_table = fsl_edma_dt_ids,
+		.pm     = &fsl_edma_pm_ops,
+	},
+	.probe          = fsl_edma_probe,
+	.remove		= fsl_edma_remove,
+};
+
+static int __init fsl_edma_init(void)
+{
+	return platform_driver_register(&fsl_edma_driver);
+}
+subsys_initcall(fsl_edma_init);
+
+static void __exit fsl_edma_exit(void)
+{
+	platform_driver_unregister(&fsl_edma_driver);
+}
+module_exit(fsl_edma_exit);
+
+MODULE_ALIAS("platform:fsl-edma");
+MODULE_DESCRIPTION("Freescale eDMA engine driver");
+MODULE_LICENSE("GPL v2");