v4.19.13 snapshot.
diff --git a/arch/arm/mach-omap2/dma.c b/arch/arm/mach-omap2/dma.c
new file mode 100644
index 0000000..a005e2a
--- /dev/null
+++ b/arch/arm/mach-omap2/dma.c
@@ -0,0 +1,295 @@
+/*
+ * OMAP2+ DMA driver
+ *
+ * Copyright (C) 2003 - 2008 Nokia Corporation
+ * Author: Juha Yrjölä <juha.yrjola@nokia.com>
+ * DMA channel linking for 1610 by Samuel Ortiz <samuel.ortiz@nokia.com>
+ * Graphics DMA and LCD DMA graphics tranformations
+ * by Imre Deak <imre.deak@nokia.com>
+ * OMAP2/3 support Copyright (C) 2004-2007 Texas Instruments, Inc.
+ * Some functions based on earlier dma-omap.c Copyright (C) 2001 RidgeRun, Inc.
+ *
+ * Copyright (C) 2009 Texas Instruments
+ * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
+ *
+ * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/
+ * Converted DMA library into platform driver
+ *	- G, Manjunath Kondaiah <manjugk@ti.com>
+ *
+ * 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/err.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/of.h>
+#include <linux/omap-dma.h>
+
+#include "soc.h"
+#include "omap_hwmod.h"
+#include "omap_device.h"
+
+static enum omap_reg_offsets dma_common_ch_end;
+
+static const struct omap_dma_reg reg_map[] = {
+	[REVISION]	= { 0x0000, 0x00, OMAP_DMA_REG_32BIT },
+	[GCR]		= { 0x0078, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQSTATUS_L0]	= { 0x0008, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQSTATUS_L1]	= { 0x000c, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQSTATUS_L2]	= { 0x0010, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQSTATUS_L3]	= { 0x0014, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQENABLE_L0]	= { 0x0018, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQENABLE_L1]	= { 0x001c, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQENABLE_L2]	= { 0x0020, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQENABLE_L3]	= { 0x0024, 0x00, OMAP_DMA_REG_32BIT },
+	[SYSSTATUS]	= { 0x0028, 0x00, OMAP_DMA_REG_32BIT },
+	[OCP_SYSCONFIG]	= { 0x002c, 0x00, OMAP_DMA_REG_32BIT },
+	[CAPS_0]	= { 0x0064, 0x00, OMAP_DMA_REG_32BIT },
+	[CAPS_2]	= { 0x006c, 0x00, OMAP_DMA_REG_32BIT },
+	[CAPS_3]	= { 0x0070, 0x00, OMAP_DMA_REG_32BIT },
+	[CAPS_4]	= { 0x0074, 0x00, OMAP_DMA_REG_32BIT },
+
+	/* Common register offsets */
+	[CCR]		= { 0x0080, 0x60, OMAP_DMA_REG_32BIT },
+	[CLNK_CTRL]	= { 0x0084, 0x60, OMAP_DMA_REG_32BIT },
+	[CICR]		= { 0x0088, 0x60, OMAP_DMA_REG_32BIT },
+	[CSR]		= { 0x008c, 0x60, OMAP_DMA_REG_32BIT },
+	[CSDP]		= { 0x0090, 0x60, OMAP_DMA_REG_32BIT },
+	[CEN]		= { 0x0094, 0x60, OMAP_DMA_REG_32BIT },
+	[CFN]		= { 0x0098, 0x60, OMAP_DMA_REG_32BIT },
+	[CSEI]		= { 0x00a4, 0x60, OMAP_DMA_REG_32BIT },
+	[CSFI]		= { 0x00a8, 0x60, OMAP_DMA_REG_32BIT },
+	[CDEI]		= { 0x00ac, 0x60, OMAP_DMA_REG_32BIT },
+	[CDFI]		= { 0x00b0, 0x60, OMAP_DMA_REG_32BIT },
+	[CSAC]		= { 0x00b4, 0x60, OMAP_DMA_REG_32BIT },
+	[CDAC]		= { 0x00b8, 0x60, OMAP_DMA_REG_32BIT },
+
+	/* Channel specific register offsets */
+	[CSSA]		= { 0x009c, 0x60, OMAP_DMA_REG_32BIT },
+	[CDSA]		= { 0x00a0, 0x60, OMAP_DMA_REG_32BIT },
+	[CCEN]		= { 0x00bc, 0x60, OMAP_DMA_REG_32BIT },
+	[CCFN]		= { 0x00c0, 0x60, OMAP_DMA_REG_32BIT },
+	[COLOR]		= { 0x00c4, 0x60, OMAP_DMA_REG_32BIT },
+
+	/* OMAP4 specific registers */
+	[CDP]		= { 0x00d0, 0x60, OMAP_DMA_REG_32BIT },
+	[CNDP]		= { 0x00d4, 0x60, OMAP_DMA_REG_32BIT },
+	[CCDN]		= { 0x00d8, 0x60, OMAP_DMA_REG_32BIT },
+};
+
+static void __iomem *dma_base;
+static inline void dma_write(u32 val, int reg, int lch)
+{
+	void __iomem *addr = dma_base;
+
+	addr += reg_map[reg].offset;
+	addr += reg_map[reg].stride * lch;
+
+	writel_relaxed(val, addr);
+}
+
+static inline u32 dma_read(int reg, int lch)
+{
+	void __iomem *addr = dma_base;
+
+	addr += reg_map[reg].offset;
+	addr += reg_map[reg].stride * lch;
+
+	return readl_relaxed(addr);
+}
+
+static void omap2_clear_dma(int lch)
+{
+	int i;
+
+	for (i = CSDP; i <= dma_common_ch_end; i += 1)
+		dma_write(0, i, lch);
+}
+
+static void omap2_show_dma_caps(void)
+{
+	u8 revision = dma_read(REVISION, 0) & 0xff;
+	printk(KERN_INFO "OMAP DMA hardware revision %d.%d\n",
+				revision >> 4, revision & 0xf);
+}
+
+static unsigned configure_dma_errata(void)
+{
+	unsigned errata = 0;
+
+	/*
+	 * Errata applicable for OMAP2430ES1.0 and all omap2420
+	 *
+	 * I.
+	 * Erratum ID: Not Available
+	 * Inter Frame DMA buffering issue DMA will wrongly
+	 * buffer elements if packing and bursting is enabled. This might
+	 * result in data gets stalled in FIFO at the end of the block.
+	 * Workaround: DMA channels must have BUFFERING_DISABLED bit set to
+	 * guarantee no data will stay in the DMA FIFO in case inter frame
+	 * buffering occurs
+	 *
+	 * II.
+	 * Erratum ID: Not Available
+	 * DMA may hang when several channels are used in parallel
+	 * In the following configuration, DMA channel hanging can occur:
+	 * a. Channel i, hardware synchronized, is enabled
+	 * b. Another channel (Channel x), software synchronized, is enabled.
+	 * c. Channel i is disabled before end of transfer
+	 * d. Channel i is reenabled.
+	 * e. Steps 1 to 4 are repeated a certain number of times.
+	 * f. A third channel (Channel y), software synchronized, is enabled.
+	 * Channel x and Channel y may hang immediately after step 'f'.
+	 * Workaround:
+	 * For any channel used - make sure NextLCH_ID is set to the value j.
+	 */
+	if (cpu_is_omap2420() || (cpu_is_omap2430() &&
+				(omap_type() == OMAP2430_REV_ES1_0))) {
+
+		SET_DMA_ERRATA(DMA_ERRATA_IFRAME_BUFFERING);
+		SET_DMA_ERRATA(DMA_ERRATA_PARALLEL_CHANNELS);
+	}
+
+	/*
+	 * Erratum ID: i378: OMAP2+: sDMA Channel is not disabled
+	 * after a transaction error.
+	 * Workaround: SW should explicitely disable the channel.
+	 */
+	if (cpu_class_is_omap2())
+		SET_DMA_ERRATA(DMA_ERRATA_i378);
+
+	/*
+	 * Erratum ID: i541: sDMA FIFO draining does not finish
+	 * If sDMA channel is disabled on the fly, sDMA enters standby even
+	 * through FIFO Drain is still in progress
+	 * Workaround: Put sDMA in NoStandby more before a logical channel is
+	 * disabled, then put it back to SmartStandby right after the channel
+	 * finishes FIFO draining.
+	 */
+	if (cpu_is_omap34xx())
+		SET_DMA_ERRATA(DMA_ERRATA_i541);
+
+	/*
+	 * Erratum ID: i88 : Special programming model needed to disable DMA
+	 * before end of block.
+	 * Workaround: software must ensure that the DMA is configured in No
+	 * Standby mode(DMAx_OCP_SYSCONFIG.MIDLEMODE = "01")
+	 */
+	if (omap_type() == OMAP3430_REV_ES1_0)
+		SET_DMA_ERRATA(DMA_ERRATA_i88);
+
+	/*
+	 * Erratum 3.2/3.3: sometimes 0 is returned if CSAC/CDAC is
+	 * read before the DMA controller finished disabling the channel.
+	 */
+	SET_DMA_ERRATA(DMA_ERRATA_3_3);
+
+	/*
+	 * Erratum ID: Not Available
+	 * A bug in ROM code leaves IRQ status for channels 0 and 1 uncleared
+	 * after secure sram context save and restore.
+	 * Work around: Hence we need to manually clear those IRQs to avoid
+	 * spurious interrupts. This affects only secure devices.
+	 */
+	if (cpu_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
+		SET_DMA_ERRATA(DMA_ROMCODE_BUG);
+
+	return errata;
+}
+
+static const struct dma_slave_map omap24xx_sdma_dt_map[] = {
+	/* external DMA requests when tusb6010 is used */
+	{ "musb-hdrc.1.auto", "dmareq0", SDMA_FILTER_PARAM(2) },
+	{ "musb-hdrc.1.auto", "dmareq1", SDMA_FILTER_PARAM(3) },
+	{ "musb-hdrc.1.auto", "dmareq2", SDMA_FILTER_PARAM(14) }, /* OMAP2420 only */
+	{ "musb-hdrc.1.auto", "dmareq3", SDMA_FILTER_PARAM(15) }, /* OMAP2420 only */
+	{ "musb-hdrc.1.auto", "dmareq4", SDMA_FILTER_PARAM(16) }, /* OMAP2420 only */
+	{ "musb-hdrc.1.auto", "dmareq5", SDMA_FILTER_PARAM(64) }, /* OMAP2420 only */
+};
+
+static struct omap_system_dma_plat_info dma_plat_info __initdata = {
+	.reg_map	= reg_map,
+	.channel_stride	= 0x60,
+	.show_dma_caps	= omap2_show_dma_caps,
+	.clear_dma	= omap2_clear_dma,
+	.dma_write	= dma_write,
+	.dma_read	= dma_read,
+};
+
+static struct platform_device_info omap_dma_dev_info __initdata = {
+	.name = "omap-dma-engine",
+	.id = -1,
+	.dma_mask = DMA_BIT_MASK(32),
+};
+
+/* One time initializations */
+static int __init omap2_system_dma_init_dev(struct omap_hwmod *oh, void *unused)
+{
+	struct platform_device			*pdev;
+	struct omap_system_dma_plat_info	p;
+	struct omap_dma_dev_attr		*d;
+	struct resource				*mem;
+	char					*name = "omap_dma_system";
+
+	p = dma_plat_info;
+	p.dma_attr = (struct omap_dma_dev_attr *)oh->dev_attr;
+	p.errata = configure_dma_errata();
+
+	if (soc_is_omap24xx()) {
+		/* DMA slave map for drivers not yet converted to DT */
+		p.slave_map = omap24xx_sdma_dt_map;
+		p.slavecnt = ARRAY_SIZE(omap24xx_sdma_dt_map);
+	}
+
+	pdev = omap_device_build(name, 0, oh, &p, sizeof(p));
+	if (IS_ERR(pdev)) {
+		pr_err("%s: Can't build omap_device for %s:%s.\n",
+			__func__, name, oh->name);
+		return PTR_ERR(pdev);
+	}
+
+	omap_dma_dev_info.res = pdev->resource;
+	omap_dma_dev_info.num_res = pdev->num_resources;
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!mem) {
+		dev_err(&pdev->dev, "%s: no mem resource\n", __func__);
+		return -EINVAL;
+	}
+
+	dma_base = ioremap(mem->start, resource_size(mem));
+	if (!dma_base) {
+		dev_err(&pdev->dev, "%s: ioremap fail\n", __func__);
+		return -ENOMEM;
+	}
+
+	d = oh->dev_attr;
+
+	if (cpu_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
+		d->dev_caps |= HS_CHANNELS_RESERVED;
+
+	if (platform_get_irq_byname(pdev, "0") < 0)
+		d->dev_caps |= DMA_ENGINE_HANDLE_IRQ;
+
+	/* Check the capabilities register for descriptor loading feature */
+	if (dma_read(CAPS_0, 0) & DMA_HAS_DESCRIPTOR_CAPS)
+		dma_common_ch_end = CCDN;
+	else
+		dma_common_ch_end = CCFN;
+
+	return 0;
+}
+
+static int __init omap2_system_dma_init(void)
+{
+	return omap_hwmod_for_each_by_class("dma",
+			omap2_system_dma_init_dev, NULL);
+}
+omap_arch_initcall(omap2_system_dma_init);