Merge tag 'dmaengine-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine

Pull dmaengine updates from Vinod Koul:
 "New support:

    - Qualcomm SDM670, SM6115 and SM6375 GPI controller support

    - Ingenic JZ4755 dmaengine support

    - Removal of iop-adma driver

  Updates:

   - Tegra support for dma-channel-mask

   - at_hdmac cleanup and virt-chan support for this driver"

* tag 'dmaengine-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (46 commits)
  dmaengine: Revert "dmaengine: remove s3c24xx driver"
  dmaengine: tegra: Add support for dma-channel-mask
  dt-bindings: dmaengine: Add dma-channel-mask to Tegra GPCDMA
  dmaengine: idxd: Remove linux/msi.h include
  dt-bindings: dmaengine: qcom: gpi: add compatible for SM6375
  dmaengine: idxd: Fix crc_val field for completion record
  dmaengine: at_hdmac: Convert driver to use virt-dma
  dmaengine: at_hdmac: Remove unused member of at_dma_chan
  dmaengine: at_hdmac: Rename "chan_common" to "dma_chan"
  dmaengine: at_hdmac: Rename "dma_common" to "dma_device"
  dmaengine: at_hdmac: Use bitfield access macros
  dmaengine: at_hdmac: Keep register definitions and structures private to at_hdmac.c
  dmaengine: at_hdmac: Set include entries in alphabetic order
  dmaengine: at_hdmac: Use pm_ptr()
  dmaengine: at_hdmac: Use devm_clk_get()
  dmaengine: at_hdmac: Use devm_platform_ioremap_resource
  dmaengine: at_hdmac: Use devm_kzalloc() and struct_size()
  dmaengine: at_hdmac: Introduce atc_get_llis_residue()
  dmaengine: at_hdmac: s/atc_get_bytes_left/atc_get_residue
  dmaengine: at_hdmac: Pass residue by address to avoid unnecessary implicit casts
  ...

29 files changed, 1268 insertions, 3952 deletions

diff --git a/Documentation/ABI/stable/sysfs-driver-dma-idxd b/Documentation/ABI/stable/sysfs-driver-dma-idxd
index 8e2c2c405db2..3becc9a82bdf 100644
--- a/Documentation/ABI/stable/sysfs-driver-dma-idxd
+++ b/Documentation/ABI/stable/sysfs-driver-dma-idxd
@@ -22,6 +22,7 @@ Date:           Oct 25, 2019
 KernelVersion:  5.6.0
 Contact:        dmaengine@vger.kernel.org
 Description:    The largest number of work descriptors in a batch.
+                It's not visible when the device does not support batch.
 
 What:           /sys/bus/dsa/devices/dsa<m>/max_work_queues_size
 Date:           Oct 25, 2019
@@ -49,6 +50,8 @@ Description:    The total number of read buffers supported by this device.
 		The read buffers represent resources within the DSA
 		implementation, and these resources are allocated by engines to
 		support operations. See DSA spec v1.2 9.2.4 Total Read Buffers.
+		It's not visible when the device does not support Read Buffer
+		allocation control.
 
 What:           /sys/bus/dsa/devices/dsa<m>/max_transfer_size
 Date:           Oct 25, 2019
@@ -122,6 +125,8 @@ Contact:        dmaengine@vger.kernel.org
 Description:    The maximum number of read buffers that may be in use at
 		one time by operations that access low bandwidth memory in the
 		device. See DSA spec v1.2 9.2.8 GENCFG on Global Read Buffer Limit.
+		It's not visible when the device does not support Read Buffer
+		allocation control.
 
 What:		/sys/bus/dsa/devices/dsa<m>/cmd_status
 Date:		Aug 28, 2020
@@ -205,6 +210,7 @@ KernelVersion:	5.10.0
 Contact:	dmaengine@vger.kernel.org
 Description:	The max batch size for this workqueue. Cannot exceed device
 		max batch size. Configurable parameter.
+		It's not visible when the device does not support batch.
 
 What:		/sys/bus/dsa/devices/wq<m>.<n>/ats_disable
 Date:		Nov 13, 2020
@@ -250,6 +256,8 @@ KernelVersion:	5.17.0
 Contact:	dmaengine@vger.kernel.org
 Description:	Enable the use of global read buffer limit for the group. See DSA
 		spec v1.2 9.2.18 GRPCFG Use Global Read Buffer Limit.
+		It's not visible when the device does not support Read Buffer
+		allocation control.
 
 What:		/sys/bus/dsa/devices/group<m>.<n>/read_buffers_allowed
 Date:		Dec 10, 2021
@@ -258,6 +266,8 @@ Contact:	dmaengine@vger.kernel.org
 Description:	Indicates max number of read buffers that may be in use at one time
 		by all engines in the group. See DSA spec v1.2 9.2.18 GRPCFG Read
 		Buffers Allowed.
+		It's not visible when the device does not support Read Buffer
+		allocation control.
 
 What:		/sys/bus/dsa/devices/group<m>.<n>/read_buffers_reserved
 Date:		Dec 10, 2021
@@ -266,6 +276,8 @@ Contact:	dmaengine@vger.kernel.org
 Description:	Indicates the number of Read Buffers reserved for the use of
 		engines in the group. See DSA spec v1.2 9.2.18 GRPCFG Read Buffers
 		Reserved.
+		It's not visible when the device does not support Read Buffer
+		allocation control.
 
 What:		/sys/bus/dsa/devices/group<m>.<n>/desc_progress_limit
 Date:		Sept 14, 2022
diff --git a/Documentation/devicetree/bindings/dma/ingenic,dma.yaml b/Documentation/devicetree/bindings/dma/ingenic,dma.yaml
index 3b0b3b919af8..e42b8ce948db 100644
--- a/Documentation/devicetree/bindings/dma/ingenic,dma.yaml
+++ b/Documentation/devicetree/bindings/dma/ingenic,dma.yaml
@@ -18,6 +18,7 @@ properties:
       - enum:
           - ingenic,jz4740-dma
           - ingenic,jz4725b-dma
+          - ingenic,jz4755-dma
           - ingenic,jz4760-dma
           - ingenic,jz4760-bdma
           - ingenic,jz4760-mdma
diff --git a/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml b/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml
index c8894476b6ab..851bd50ee67f 100644
--- a/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml
+++ b/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml
@@ -39,7 +39,7 @@ properties:
       Should contain all of the per-channel DMA interrupts in
       ascending order with respect to the DMA channel index.
     minItems: 1
-    maxItems: 31
+    maxItems: 32
 
   resets:
     maxItems: 1
@@ -52,6 +52,9 @@ properties:
 
   dma-coherent: true
 
+  dma-channel-mask:
+    maxItems: 1
+
 required:
   - compatible
   - reg
@@ -60,6 +63,7 @@ required:
   - reset-names
   - "#dma-cells"
   - iommus
+  - dma-channel-mask
 
 additionalProperties: false
 
@@ -108,5 +112,6 @@ examples:
         #dma-cells = <1>;
         iommus = <&smmu TEGRA186_SID_GPCDMA_0>;
         dma-coherent;
+        dma-channel-mask = <0xfffffffe>;
     };
 ...
diff --git a/Documentation/devicetree/bindings/dma/qcom,gpi.yaml b/Documentation/devicetree/bindings/dma/qcom,gpi.yaml
index eabf8a76d3a0..e7ba1c47a88e 100644
--- a/Documentation/devicetree/bindings/dma/qcom,gpi.yaml
+++ b/Documentation/devicetree/bindings/dma/qcom,gpi.yaml
@@ -18,14 +18,24 @@ allOf:
 
 properties:
   compatible:
-    enum:
-      - qcom,sc7280-gpi-dma
-      - qcom,sdm845-gpi-dma
-      - qcom,sm6350-gpi-dma
-      - qcom,sm8150-gpi-dma
-      - qcom,sm8250-gpi-dma
-      - qcom,sm8350-gpi-dma
-      - qcom,sm8450-gpi-dma
+    oneOf:
+      - enum:
+          - qcom,sdm845-gpi-dma
+          - qcom,sm6350-gpi-dma
+      - items:
+          - enum:
+              - qcom,sc7280-gpi-dma
+              - qcom,sm6115-gpi-dma
+              - qcom,sm6375-gpi-dma
+              - qcom,sm8350-gpi-dma
+              - qcom,sm8450-gpi-dma
+          - const: qcom,sm6350-gpi-dma
+      - items:
+          - enum:
+              - qcom,sdm670-gpi-dma
+              - qcom,sm8150-gpi-dma
+              - qcom,sm8250-gpi-dma
+          - const: qcom,sdm845-gpi-dma
 
   reg:
     maxItems: 1
diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst
index d2ef9fb34b7b..4249eb4239e0 100644
--- a/Documentation/driver-api/driver-model/devres.rst
+++ b/Documentation/driver-api/driver-model/devres.rst
@@ -450,6 +450,7 @@ SERDEV
 
 SLAVE DMA ENGINE
   devm_acpi_dma_controller_register()
+  devm_acpi_dma_controller_free()
 
 SPI
   devm_spi_alloc_master()
diff --git a/MAINTAINERS b/MAINTAINERS
index 204aeacc516b..9737e8dd2e8b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10460,11 +10460,6 @@ T:	git git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu.git
 F:	drivers/iommu/intel/
 F:	include/linux/intel-svm.h
 
-INTEL IOP-ADMA DMA DRIVER
-R:	Dan Williams <dan.j.williams@intel.com>
-S:	Odd fixes
-F:	drivers/dma/iop-adma.c
-
 INTEL IPU3 CSI-2 CIO2 DRIVER
 M:	Yong Zhi <yong.zhi@intel.com>
 M:	Sakari Ailus <sakari.ailus@linux.intel.com>
@@ -13629,7 +13624,6 @@ L:	dmaengine@vger.kernel.org
 S:	Supported
 F:	Documentation/devicetree/bindings/dma/atmel-dma.txt
 F:	drivers/dma/at_hdmac.c
-F:	drivers/dma/at_hdmac_regs.h
 F:	drivers/dma/at_xdmac.c
 F:	include/dt-bindings/dma/at91.h
 
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 25e111ab21f8..b6d48d54f42f 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -97,6 +97,7 @@ config AT_HDMAC
 	tristate "Atmel AHB DMA support"
 	depends on ARCH_AT91
 	select DMA_ENGINE
+	select DMA_VIRTUAL_CHANNELS
 	help
 	  Support the Atmel AHB DMA controller.
 
@@ -357,14 +358,6 @@ config INTEL_IOATDMA
 
 	  If unsure, say N.
 
-config INTEL_IOP_ADMA
-	tristate "Intel IOP32x ADMA support"
-	depends on ARCH_IOP32X || COMPILE_TEST
-	select DMA_ENGINE
-	select ASYNC_TX_ENABLE_CHANNEL_SWITCH
-	help
-	  Enable support for the Intel(R) IOP Series RAID engines.
-
 config K3_DMA
 	tristate "Hisilicon K3 DMA support"
 	depends on ARCH_HI3xxx || ARCH_HISI || COMPILE_TEST
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index 10f7d4241001..5b55ada052a7 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -44,7 +44,6 @@ obj-$(CONFIG_IMX_SDMA) += imx-sdma.o
 obj-$(CONFIG_INTEL_IDMA64) += idma64.o
 obj-$(CONFIG_INTEL_IOATDMA) += ioat/
 obj-y += idxd/
-obj-$(CONFIG_INTEL_IOP_ADMA) += iop-adma.o
 obj-$(CONFIG_K3_DMA) += k3dma.o
 obj-$(CONFIG_LPC18XX_DMAMUX) += lpc18xx-dmamux.o
 obj-$(CONFIG_MILBEAUT_HDMAC) += milbeaut-hdmac.o
diff --git a/drivers/dma/apple-admac.c b/drivers/dma/apple-admac.c
index a2cc520225d3..90f28bda29c8 100644
--- a/drivers/dma/apple-admac.c
+++ b/drivers/dma/apple-admac.c
@@ -21,6 +21,12 @@
 #define NCHANNELS_MAX	64
 #define IRQ_NOUTPUTS	4
 
+/*
+ * For allocation purposes we split the cache
+ * memory into blocks of fixed size (given in bytes).
+ */
+#define SRAM_BLOCK	2048
+
 #define RING_WRITE_SLOT		GENMASK(1, 0)
 #define RING_READ_SLOT		GENMASK(5, 4)
 #define RING_FULL		BIT(9)
@@ -36,6 +42,9 @@
 #define REG_TX_STOP		0x0004
 #define REG_RX_START		0x0008
 #define REG_RX_STOP		0x000c
+#define REG_IMPRINT		0x0090
+#define REG_TX_SRAM_SIZE	0x0094
+#define REG_RX_SRAM_SIZE	0x0098
 
 #define REG_CHAN_CTL(ch)	(0x8000 + (ch) * 0x200)
 #define REG_CHAN_CTL_RST_RINGS	BIT(0)
@@ -53,7 +62,9 @@
 #define BUS_WIDTH_FRAME_2_WORDS	0x10
 #define BUS_WIDTH_FRAME_4_WORDS	0x20
 
-#define CHAN_BUFSIZE		0x8000
+#define REG_CHAN_SRAM_CARVEOUT(ch)	(0x8050 + (ch) * 0x200)
+#define CHAN_SRAM_CARVEOUT_SIZE		GENMASK(31, 16)
+#define CHAN_SRAM_CARVEOUT_BASE		GENMASK(15, 0)
 
 #define REG_CHAN_FIFOCTL(ch)	(0x8054 + (ch) * 0x200)
 #define CHAN_FIFOCTL_LIMIT	GENMASK(31, 16)
@@ -76,6 +87,8 @@ struct admac_chan {
 	struct dma_chan chan;
 	struct tasklet_struct tasklet;
 
+	u32 carveout;
+
 	spinlock_t lock;
 	struct admac_tx *current_tx;
 	int nperiod_acks;
@@ -92,12 +105,24 @@ struct admac_chan {
 	struct list_head to_free;
 };
 
+struct admac_sram {
+	u32 size;
+	/*
+	 * SRAM_CARVEOUT has 16-bit fields, so the SRAM cannot be larger than
+	 * 64K and a 32-bit bitfield over 2K blocks covers it.
+	 */
+	u32 allocated;
+};
+
 struct admac_data {
 	struct dma_device dma;
 	struct device *dev;
 	__iomem void *base;
 	struct reset_control *rstc;
 
+	struct mutex cache_alloc_lock;
+	struct admac_sram txcache, rxcache;
+
 	int irq;
 	int irq_index;
 	int nchannels;
@@ -118,6 +143,60 @@ struct admac_tx {
 	struct list_head node;
 };
 
+static int admac_alloc_sram_carveout(struct admac_data *ad,
+				     enum dma_transfer_direction dir,
+				     u32 *out)
+{
+	struct admac_sram *sram;
+	int i, ret = 0, nblocks;
+
+	if (dir == DMA_MEM_TO_DEV)
+		sram = &ad->txcache;
+	else
+		sram = &ad->rxcache;
+
+	mutex_lock(&ad->cache_alloc_lock);
+
+	nblocks = sram->size / SRAM_BLOCK;
+	for (i = 0; i < nblocks; i++)
+		if (!(sram->allocated & BIT(i)))
+			break;
+
+	if (i < nblocks) {
+		*out = FIELD_PREP(CHAN_SRAM_CARVEOUT_BASE, i * SRAM_BLOCK) |
+			FIELD_PREP(CHAN_SRAM_CARVEOUT_SIZE, SRAM_BLOCK);
+		sram->allocated |= BIT(i);
+	} else {
+		ret = -EBUSY;
+	}
+
+	mutex_unlock(&ad->cache_alloc_lock);
+
+	return ret;
+}
+
+static void admac_free_sram_carveout(struct admac_data *ad,
+				     enum dma_transfer_direction dir,
+				     u32 carveout)
+{
+	struct admac_sram *sram;
+	u32 base = FIELD_GET(CHAN_SRAM_CARVEOUT_BASE, carveout);
+	int i;
+
+	if (dir == DMA_MEM_TO_DEV)
+		sram = &ad->txcache;
+	else
+		sram = &ad->rxcache;
+
+	if (WARN_ON(base >= sram->size))
+		return;
+
+	mutex_lock(&ad->cache_alloc_lock);
+	i = base / SRAM_BLOCK;
+	sram->allocated &= ~BIT(i);
+	mutex_unlock(&ad->cache_alloc_lock);
+}
+
 static void admac_modify(struct admac_data *ad, int reg, u32 mask, u32 val)
 {
 	void __iomem *addr = ad->base + reg;
@@ -466,15 +545,28 @@ static void admac_synchronize(struct dma_chan *chan)
 static int admac_alloc_chan_resources(struct dma_chan *chan)
 {
 	struct admac_chan *adchan = to_admac_chan(chan);
+	struct admac_data *ad = adchan->host;
+	int ret;
 
 	dma_cookie_init(&adchan->chan);
+	ret = admac_alloc_sram_carveout(ad, admac_chan_direction(adchan->no),
+					&adchan->carveout);
+	if (ret < 0)
+		return ret;
+
+	writel_relaxed(adchan->carveout,
+		       ad->base + REG_CHAN_SRAM_CARVEOUT(adchan->no));
 	return 0;
 }
 
 static void admac_free_chan_resources(struct dma_chan *chan)
 {
+	struct admac_chan *adchan = to_admac_chan(chan);
+
 	admac_terminate_all(chan);
 	admac_synchronize(chan);
+	admac_free_sram_carveout(adchan->host, admac_chan_direction(adchan->no),
+				 adchan->carveout);
 }
 
 static struct dma_chan *admac_dma_of_xlate(struct of_phandle_args *dma_spec,
@@ -712,6 +804,7 @@ static int admac_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, ad);
 	ad->dev = &pdev->dev;
 	ad->nchannels = nchannels;
+	mutex_init(&ad->cache_alloc_lock);
 
 	/*
 	 * The controller has 4 IRQ outputs. Try them all until
@@ -801,6 +894,13 @@ static int admac_probe(struct platform_device *pdev)
 		goto free_irq;
 	}
 
+	ad->txcache.size = readl_relaxed(ad->base + REG_TX_SRAM_SIZE);
+	ad->rxcache.size = readl_relaxed(ad->base + REG_RX_SRAM_SIZE);
+
+	dev_info(&pdev->dev, "Audio DMA Controller\n");
+	dev_info(&pdev->dev, "imprint %x TX cache %u RX cache %u\n",
+		 readl_relaxed(ad->base + REG_IMPRINT), ad->txcache.size, ad->rxcache.size);
+
 	return 0;
 
 free_irq:
diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index 858bd64f1313..8858470246e1 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -3,6 +3,7 @@
  * Driver for the Atmel AHB DMA Controller (aka HDMA or DMAC on AT91 systems)
  *
  * Copyright (C) 2008 Atmel Corporation
+ * Copyright (C) 2022 Microchip Technology, Inc. and its subsidiaries
  *
  * This supports the Atmel AHB DMA Controller found in several Atmel SoCs.
  * The only Atmel DMA Controller that is not covered by this driver is the one
@@ -10,20 +11,22 @@
  */
 
 #include <dt-bindings/dma/at91.h>
+#include <linux/bitfield.h>
 #include <linux/clk.h>
 #include <linux/dmaengine.h>
-#include <linux/dma-mapping.h>
 #include <linux/dmapool.h>
+#include <linux/dma-mapping.h>
 #include <linux/interrupt.h>
 #include <linux/module.h>
-#include <linux/platform_device.h>
-#include <linux/slab.h>
 #include <linux/of.h>
+#include <linux/overflow.h>
 #include <linux/of_device.h>
 #include <linux/of_dma.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
 
-#include "at_hdmac_regs.h"
 #include "dmaengine.h"
+#include "virt-dma.h"
 
 /*
  * Glossary
@@ -34,9 +37,449 @@
  * atc_	/ atchan	: ATmel DMA Channel entity related
  */
 
-#define	ATC_DEFAULT_CFG		(ATC_FIFOCFG_HALFFIFO)
-#define	ATC_DEFAULT_CTRLB	(ATC_SIF(AT_DMA_MEM_IF) \
-				|ATC_DIF(AT_DMA_MEM_IF))
+#define	AT_DMA_MAX_NR_CHANNELS	8
+
+/* Global Configuration Register */
+#define AT_DMA_GCFG		0x00
+#define AT_DMA_IF_BIGEND(i)	BIT((i))	/* AHB-Lite Interface i in Big-endian mode */
+#define AT_DMA_ARB_CFG		BIT(4)		/* Arbiter mode. */
+
+/* Controller Enable Register */
+#define AT_DMA_EN		0x04
+#define AT_DMA_ENABLE		BIT(0)
+
+/* Software Single Request Register */
+#define AT_DMA_SREQ		0x08
+#define AT_DMA_SSREQ(x)		BIT((x) << 1)		/* Request a source single transfer on channel x */
+#define AT_DMA_DSREQ(x)		BIT(1 + ((x) << 1))	/* Request a destination single transfer on channel x */
+
+/* Software Chunk Transfer Request Register */
+#define AT_DMA_CREQ		0x0c
+#define AT_DMA_SCREQ(x)		BIT((x) << 1)		/* Request a source chunk transfer on channel x */
+#define AT_DMA_DCREQ(x)		BIT(1 + ((x) << 1))	/* Request a destination chunk transfer on channel x */
+
+/* Software Last Transfer Flag Register */
+#define AT_DMA_LAST		0x10
+#define AT_DMA_SLAST(x)		BIT((x) << 1)		/* This src rq is last tx of buffer on channel x */
+#define AT_DMA_DLAST(x)		BIT(1 + ((x) << 1))	/* This dst rq is last tx of buffer on channel x */
+
+/* Request Synchronization Register */
+#define AT_DMA_SYNC		0x14
+#define AT_DMA_SYR(h)		BIT((h))		/* Synchronize handshake line h */
+
+/* Error, Chained Buffer transfer completed and Buffer transfer completed Interrupt registers */
+#define AT_DMA_EBCIER		0x18			/* Enable register */
+#define AT_DMA_EBCIDR		0x1c			/* Disable register */
+#define AT_DMA_EBCIMR		0x20			/* Mask Register */
+#define AT_DMA_EBCISR		0x24			/* Status Register */
+#define AT_DMA_CBTC_OFFSET	8
+#define AT_DMA_ERR_OFFSET	16
+#define AT_DMA_BTC(x)		BIT((x))
+#define AT_DMA_CBTC(x)		BIT(AT_DMA_CBTC_OFFSET + (x))
+#define AT_DMA_ERR(x)		BIT(AT_DMA_ERR_OFFSET + (x))
+
+/* Channel Handler Enable Register */
+#define AT_DMA_CHER		0x28
+#define AT_DMA_ENA(x)		BIT((x))
+#define AT_DMA_SUSP(x)		BIT(8 + (x))
+#define AT_DMA_KEEP(x)		BIT(24 + (x))
+
+/* Channel Handler Disable Register */
+#define AT_DMA_CHDR		0x2c
+#define AT_DMA_DIS(x)		BIT(x)
+#define AT_DMA_RES(x)		BIT(8 + (x))
+
+/* Channel Handler Status Register */
+#define AT_DMA_CHSR		0x30
+#define AT_DMA_EMPT(x)		BIT(16 + (x))
+#define AT_DMA_STAL(x)		BIT(24 + (x))
+
+/* Channel registers base address */
+#define AT_DMA_CH_REGS_BASE	0x3c
+#define ch_regs(x)		(AT_DMA_CH_REGS_BASE + (x) * 0x28) /* Channel x base addr */
+
+/* Hardware register offset for each channel */
+#define ATC_SADDR_OFFSET	0x00	/* Source Address Register */
+#define ATC_DADDR_OFFSET	0x04	/* Destination Address Register */
+#define ATC_DSCR_OFFSET		0x08	/* Descriptor Address Register */
+#define ATC_CTRLA_OFFSET	0x0c	/* Control A Register */
+#define ATC_CTRLB_OFFSET	0x10	/* Control B Register */
+#define ATC_CFG_OFFSET		0x14	/* Configuration Register */
+#define ATC_SPIP_OFFSET		0x18	/* Src PIP Configuration Register */
+#define ATC_DPIP_OFFSET		0x1c	/* Dst PIP Configuration Register */
+
+
+/* Bitfield definitions */
+
+/* Bitfields in DSCR */
+#define ATC_DSCR_IF		GENMASK(1, 0)	/* Dsc feched via AHB-Lite Interface */
+
+/* Bitfields in CTRLA */
+#define ATC_BTSIZE_MAX		GENMASK(15, 0)	/* Maximum Buffer Transfer Size */
+#define ATC_BTSIZE		GENMASK(15, 0)	/* Buffer Transfer Size */
+#define ATC_SCSIZE		GENMASK(18, 16)	/* Source Chunk Transfer Size */
+#define ATC_DCSIZE		GENMASK(22, 20)	/* Destination Chunk Transfer Size */
+#define ATC_SRC_WIDTH		GENMASK(25, 24)	/* Source Single Transfer Size */
+#define ATC_DST_WIDTH		GENMASK(29, 28)	/* Destination Single Transfer Size */
+#define ATC_DONE		BIT(31)	/* Tx Done (only written back in descriptor) */
+
+/* Bitfields in CTRLB */
+#define ATC_SIF			GENMASK(1, 0)	/* Src tx done via AHB-Lite Interface i */
+#define ATC_DIF			GENMASK(5, 4)	/* Dst tx done via AHB-Lite Interface i */
+#define AT_DMA_MEM_IF		0x0		/* interface 0 as memory interface */
+#define AT_DMA_PER_IF		0x1		/* interface 1 as peripheral interface */
+#define ATC_SRC_PIP		BIT(8)		/* Source Picture-in-Picture enabled */
+#define ATC_DST_PIP		BIT(12)		/* Destination Picture-in-Picture enabled */
+#define ATC_SRC_DSCR_DIS	BIT(16)		/* Src Descriptor fetch disable */
+#define ATC_DST_DSCR_DIS	BIT(20)		/* Dst Descriptor fetch disable */
+#define ATC_FC			GENMASK(22, 21)	/* Choose Flow Controller */
+#define ATC_FC_MEM2MEM		0x0		/* Mem-to-Mem (DMA) */
+#define ATC_FC_MEM2PER		0x1		/* Mem-to-Periph (DMA) */
+#define ATC_FC_PER2MEM		0x2		/* Periph-to-Mem (DMA) */
+#define ATC_FC_PER2PER		0x3		/* Periph-to-Periph (DMA) */
+#define ATC_FC_PER2MEM_PER	0x4		/* Periph-to-Mem (Peripheral) */
+#define ATC_FC_MEM2PER_PER	0x5		/* Mem-to-Periph (Peripheral) */
+#define ATC_FC_PER2PER_SRCPER	0x6		/* Periph-to-Periph (Src Peripheral) */
+#define ATC_FC_PER2PER_DSTPER	0x7		/* Periph-to-Periph (Dst Peripheral) */
+#define ATC_SRC_ADDR_MODE	GENMASK(25, 24)
+#define ATC_SRC_ADDR_MODE_INCR	0x0		/* Incrementing Mode */
+#define ATC_SRC_ADDR_MODE_DECR	0x1		/* Decrementing Mode */
+#define ATC_SRC_ADDR_MODE_FIXED	0x2		/* Fixed Mode */
+#define ATC_DST_ADDR_MODE	GENMASK(29, 28)
+#define ATC_DST_ADDR_MODE_INCR	0x0		/* Incrementing Mode */
+#define ATC_DST_ADDR_MODE_DECR	0x1		/* Decrementing Mode */
+#define ATC_DST_ADDR_MODE_FIXED	0x2		/* Fixed Mode */
+#define ATC_IEN			BIT(30)		/* BTC interrupt enable (active low) */
+#define ATC_AUTO		BIT(31)		/* Auto multiple buffer tx enable */
+
+/* Bitfields in CFG */
+#define ATC_PER_MSB(h)	((0x30U & (h)) >> 4)	/* Extract most significant bits of a handshaking identifier */
+
+#define ATC_SRC_PER		GENMASK(3, 0)	/* Channel src rq associated with periph handshaking ifc h */
+#define ATC_DST_PER		GENMASK(7, 4)	/* Channel dst rq associated with periph handshaking ifc h */
+#define ATC_SRC_REP		BIT(8)		/* Source Replay Mod */
+#define ATC_SRC_H2SEL		BIT(9)		/* Source Handshaking Mod */
+#define ATC_SRC_PER_MSB		GENMASK(11, 10)	/* Channel src rq (most significant bits) */
+#define ATC_DST_REP		BIT(12)		/* Destination Replay Mod */
+#define ATC_DST_H2SEL		BIT(13)		/* Destination Handshaking Mod */
+#define ATC_DST_PER_MSB		GENMASK(15, 14)	/* Channel dst rq (most significant bits) */
+#define ATC_SOD			BIT(16)		/* Stop On Done */
+#define ATC_LOCK_IF		BIT(20)		/* Interface Lock */
+#define ATC_LOCK_B		BIT(21)		/* AHB Bus Lock */
+#define ATC_LOCK_IF_L		BIT(22)		/* Master Interface Arbiter Lock */
+#define ATC_AHB_PROT		GENMASK(26, 24)	/* AHB Protection */
+#define ATC_FIFOCFG		GENMASK(29, 28)	/* FIFO Request Configuration */
+#define ATC_FIFOCFG_LARGESTBURST	0x0
+#define ATC_FIFOCFG_HALFFIFO		0x1
+#define ATC_FIFOCFG_ENOUGHSPACE		0x2
+
+/* Bitfields in SPIP */
+#define ATC_SPIP_HOLE		GENMASK(15, 0)
+#define ATC_SPIP_BOUNDARY	GENMASK(25, 16)
+
+/* Bitfields in DPIP */
+#define ATC_DPIP_HOLE		GENMASK(15, 0)
+#define ATC_DPIP_BOUNDARY	GENMASK(25, 16)
+
+#define ATC_SRC_PER_ID(id)	(FIELD_PREP(ATC_SRC_PER_MSB, (id)) |	\
+				 FIELD_PREP(ATC_SRC_PER, (id)))
+#define ATC_DST_PER_ID(id)	(FIELD_PREP(ATC_DST_PER_MSB, (id)) |	\
+				 FIELD_PREP(ATC_DST_PER, (id)))
+
+
+
+/*--  descriptors  -----------------------------------------------------*/
+
+/* LLI == Linked List Item; aka DMA buffer descriptor */
+struct at_lli {
+	/* values that are not changed by hardware */
+	u32 saddr;
+	u32 daddr;
+	/* value that may get written back: */
+	u32 ctrla;
+	/* more values that are not changed by hardware */
+	u32 ctrlb;
+	u32 dscr;	/* chain to next lli */
+};
+
+/**
+ * struct atdma_sg - atdma scatter gather entry
+ * @len: length of the current Linked List Item.
+ * @lli: linked list item that is passed to the DMA controller
+ * @lli_phys: physical address of the LLI.
+ */
+struct atdma_sg {
+	unsigned int len;
+	struct at_lli *lli;
+	dma_addr_t lli_phys;
+};
+
+/**
+ * struct at_desc - software descriptor
+ * @vd: pointer to the virtual dma descriptor.
+ * @atchan: pointer to the atmel dma channel.
+ * @total_len: total transaction byte count
+ * @sg_len: number of sg entries.
+ * @sg: array of sgs.
+ */
+struct at_desc {
+	struct				virt_dma_desc vd;
+	struct				at_dma_chan *atchan;
+	size_t				total_len;
+	unsigned int			sglen;
+	/* Interleaved data */
+	size_t				boundary;
+	size_t				dst_hole;
+	size_t				src_hole;
+
+	/* Memset temporary buffer */
+	bool				memset_buffer;
+	dma_addr_t			memset_paddr;
+	int				*memset_vaddr;
+	struct atdma_sg			sg[];
+};
+
+/*--  Channels  --------------------------------------------------------*/
+
+/**
+ * atc_status - information bits stored in channel status flag
+ *
+ * Manipulated with atomic operations.
+ */
+enum atc_status {
+	ATC_IS_PAUSED = 1,
+	ATC_IS_CYCLIC = 24,
+};
+
+/**
+ * struct at_dma_chan - internal representation of an Atmel HDMAC channel
+ * @vc: virtual dma channel entry.
+ * @atdma: pointer to the driver data.
+ * @ch_regs: memory mapped register base
+ * @mask: channel index in a mask
+ * @per_if: peripheral interface
+ * @mem_if: memory interface
+ * @status: transmit status information from irq/prep* functions
+ *                to tasklet (use atomic operations)
+ * @save_cfg: configuration register that is saved on suspend/resume cycle
+ * @save_dscr: for cyclic operations, preserve next descriptor address in
+ *             the cyclic list on suspend/resume cycle
+ * @dma_sconfig: configuration for slave transfers, passed via
+ * .device_config
+ * @desc: pointer to the atmel dma descriptor.
+ */
+struct at_dma_chan {
+	struct virt_dma_chan	vc;
+	struct at_dma		*atdma;
+	void __iomem		*ch_regs;
+	u8			mask;
+	u8			per_if;
+	u8			mem_if;
+	unsigned long		status;
+	u32			save_cfg;
+	u32			save_dscr;
+	struct dma_slave_config	dma_sconfig;
+	bool			cyclic;
+	struct at_desc		*desc;
+};
+
+#define	channel_readl(atchan, name) \
+	__raw_readl((atchan)->ch_regs + ATC_##name##_OFFSET)
+
+#define	channel_writel(atchan, name, val) \
+	__raw_writel((val), (atchan)->ch_regs + ATC_##name##_OFFSET)
+
+/*
+ * Fix sconfig's burst size according to at_hdmac. We need to convert them as:
+ * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3, 32 -> 4, 64 -> 5, 128 -> 6, 256 -> 7.
+ *
+ * This can be done by finding most significant bit set.
+ */
+static inline void convert_burst(u32 *maxburst)
+{
+	if (*maxburst > 1)
+		*maxburst = fls(*maxburst) - 2;
+	else
+		*maxburst = 0;
+}
+
+/*
+ * Fix sconfig's bus width according to at_hdmac.
+ * 1 byte -> 0, 2 bytes -> 1, 4 bytes -> 2.
+ */
+static inline u8 convert_buswidth(enum dma_slave_buswidth addr_width)
+{
+	switch (addr_width) {
+	case DMA_SLAVE_BUSWIDTH_2_BYTES:
+		return 1;
+	case DMA_SLAVE_BUSWIDTH_4_BYTES:
+		return 2;
+	default:
+		/* For 1 byte width or fallback */
+		return 0;
+	}
+}
+
+/*--  Controller  ------------------------------------------------------*/
+
+/**
+ * struct at_dma - internal representation of an Atmel HDMA Controller
+ * @dma_device: dmaengine dma_device object members
+ * @atdma_devtype: identifier of DMA controller compatibility
+ * @ch_regs: memory mapped register base
+ * @clk: dma controller clock
+ * @save_imr: interrupt mask register that is saved on suspend/resume cycle
+ * @all_chan_mask: all channels availlable in a mask
+ * @lli_pool: hw lli table
+ * @chan: channels table to store at_dma_chan structures
+ */
+struct at_dma {
+	struct dma_device	dma_device;
+	void __iomem		*regs;
+	struct clk		*clk;
+	u32			save_imr;</