drivers/dma/at_hdmac_regs.h - linux - Git at Google

 /*
  * Header file for the Atmel AHB DMA Controller driver
  *
  * Copyright (C) 2008 Atmel Corporation
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  */
 #ifndef AT_HDMAC_REGS_H
 #define	AT_HDMAC_REGS_H

 #include <linux/platform_data/dma-atmel.h>

 #define	AT_DMA_MAX_NR_CHANNELS	8


 #define	AT_DMA_GCFG	0x00	/* Global Configuration Register */
 #define		AT_DMA_IF_BIGEND(i)	(0x1 << (i))	/* AHB-Lite Interface i in Big-endian mode */
 #define		AT_DMA_ARB_CFG	(0x1 << 4)	/* Arbiter mode. */
 #define			AT_DMA_ARB_CFG_FIXED		(0x0 << 4)
 #define			AT_DMA_ARB_CFG_ROUND_ROBIN	(0x1 << 4)

 #define	AT_DMA_EN	0x04	/* Controller Enable Register */
 #define		AT_DMA_ENABLE	(0x1 << 0)

 #define	AT_DMA_SREQ	0x08	/* Software Single Request Register */
 #define		AT_DMA_SSREQ(x)	(0x1 << ((x) << 1))		/* Request a source single transfer on channel x */
 #define		AT_DMA_DSREQ(x)	(0x1 << (1 + ((x) << 1)))	/* Request a destination single transfer on channel x */

 #define	AT_DMA_CREQ	0x0C	/* Software Chunk Transfer Request Register */
 #define		AT_DMA_SCREQ(x)	(0x1 << ((x) << 1))		/* Request a source chunk transfer on channel x */
 #define		AT_DMA_DCREQ(x)	(0x1 << (1 + ((x) << 1)))	/* Request a destination chunk transfer on channel x */

 #define	AT_DMA_LAST	0x10	/* Software Last Transfer Flag Register */
 #define		AT_DMA_SLAST(x)	(0x1 << ((x) << 1))		/* This src rq is last tx of buffer on channel x */
 #define		AT_DMA_DLAST(x)	(0x1 << (1 + ((x) << 1)))	/* This dst rq is last tx of buffer on channel x */

 #define	AT_DMA_SYNC	0x14	/* Request Synchronization Register */
 #define		AT_DMA_SYR(h)	(0x1 << (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)	(0x1 << (x))
 #define		AT_DMA_CBTC(x)	(0x1 << (AT_DMA_CBTC_OFFSET + (x)))
 #define		AT_DMA_ERR(x)	(0x1 << (AT_DMA_ERR_OFFSET + (x)))

 #define	AT_DMA_CHER	0x28	/* Channel Handler Enable Register */
 #define		AT_DMA_ENA(x)	(0x1 << (x))
 #define		AT_DMA_SUSP(x)	(0x1 << ( 8 + (x)))
 #define		AT_DMA_KEEP(x)	(0x1 << (24 + (x)))

 #define	AT_DMA_CHDR	0x2C	/* Channel Handler Disable Register */
 #define		AT_DMA_DIS(x)	(0x1 << (x))
 #define		AT_DMA_RES(x)	(0x1 << ( 8 + (x)))

 #define	AT_DMA_CHSR	0x30	/* Channel Handler Status Register */
 #define		AT_DMA_EMPT(x)	(0x1 << (16 + (x)))
 #define		AT_DMA_STAL(x)	(0x1 << (24 + (x)))


 #define	AT_DMA_CH_REGS_BASE	0x3C	/* Channel registers base address */
 #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(i)		(0x3 & (i))	/* Dsc feched via AHB-Lite Interface i */

 /* Bitfields in CTRLA */
 #define	ATC_BTSIZE_MAX		0xFFFFUL	/* Maximum Buffer Transfer Size */
 #define	ATC_BTSIZE(x)		(ATC_BTSIZE_MAX & (x)) /* Buffer Transfer Size */
 #define	ATC_SCSIZE_MASK		(0x7 << 16)	/* Source Chunk Transfer Size */
 #define		ATC_SCSIZE(x)		(ATC_SCSIZE_MASK & ((x) << 16))
 #define		ATC_SCSIZE_1		(0x0 << 16)
 #define		ATC_SCSIZE_4		(0x1 << 16)
 #define		ATC_SCSIZE_8		(0x2 << 16)
 #define		ATC_SCSIZE_16		(0x3 << 16)
 #define		ATC_SCSIZE_32		(0x4 << 16)
 #define		ATC_SCSIZE_64		(0x5 << 16)
 #define		ATC_SCSIZE_128		(0x6 << 16)
 #define		ATC_SCSIZE_256		(0x7 << 16)
 #define	ATC_DCSIZE_MASK		(0x7 << 20)	/* Destination Chunk Transfer Size */
 #define		ATC_DCSIZE(x)		(ATC_DCSIZE_MASK & ((x) << 20))
 #define		ATC_DCSIZE_1		(0x0 << 20)
 #define		ATC_DCSIZE_4		(0x1 << 20)
 #define		ATC_DCSIZE_8		(0x2 << 20)
 #define		ATC_DCSIZE_16		(0x3 << 20)
 #define		ATC_DCSIZE_32		(0x4 << 20)
 #define		ATC_DCSIZE_64		(0x5 << 20)
 #define		ATC_DCSIZE_128		(0x6 << 20)
 #define		ATC_DCSIZE_256		(0x7 << 20)
 #define	ATC_SRC_WIDTH_MASK	(0x3 << 24)	/* Source Single Transfer Size */
 #define		ATC_SRC_WIDTH(x)	((x) << 24)
 #define		ATC_SRC_WIDTH_BYTE	(0x0 << 24)
 #define		ATC_SRC_WIDTH_HALFWORD	(0x1 << 24)
 #define		ATC_SRC_WIDTH_WORD	(0x2 << 24)
 #define	ATC_DST_WIDTH_MASK	(0x3 << 28)	/* Destination Single Transfer Size */
 #define		ATC_DST_WIDTH(x)	((x) << 28)
 #define		ATC_DST_WIDTH_BYTE	(0x0 << 28)
 #define		ATC_DST_WIDTH_HALFWORD	(0x1 << 28)
 #define		ATC_DST_WIDTH_WORD	(0x2 << 28)
 #define	ATC_DONE		(0x1 << 31)	/* Tx Done (only written back in descriptor) */

 /* Bitfields in CTRLB */
 #define	ATC_SIF(i)		(0x3 & (i))	/* Src tx done via AHB-Lite Interface i */
 #define	ATC_DIF(i)		((0x3 & (i)) <<  4)	/* Dst tx done via AHB-Lite Interface i */
 				  /* Specify AHB interfaces */
 #define AT_DMA_MEM_IF		0 /* interface 0 as memory interface */
 #define AT_DMA_PER_IF		1 /* interface 1 as peripheral interface */

 #define	ATC_SRC_PIP		(0x1 <<  8)	/* Source Picture-in-Picture enabled */
 #define	ATC_DST_PIP		(0x1 << 12)	/* Destination Picture-in-Picture enabled */
 #define	ATC_SRC_DSCR_DIS	(0x1 << 16)	/* Src Descriptor fetch disable */
 #define	ATC_DST_DSCR_DIS	(0x1 << 20)	/* Dst Descriptor fetch disable */
 #define	ATC_FC_MASK		(0x7 << 21)	/* Choose Flow Controller */
 #define		ATC_FC_MEM2MEM		(0x0 << 21)	/* Mem-to-Mem (DMA) */
 #define		ATC_FC_MEM2PER		(0x1 << 21)	/* Mem-to-Periph (DMA) */
 #define		ATC_FC_PER2MEM		(0x2 << 21)	/* Periph-to-Mem (DMA) */
 #define		ATC_FC_PER2PER		(0x3 << 21)	/* Periph-to-Periph (DMA) */
 #define		ATC_FC_PER2MEM_PER	(0x4 << 21)	/* Periph-to-Mem (Peripheral) */
 #define		ATC_FC_MEM2PER_PER	(0x5 << 21)	/* Mem-to-Periph (Peripheral) */
 #define		ATC_FC_PER2PER_SRCPER	(0x6 << 21)	/* Periph-to-Periph (Src Peripheral) */
 #define		ATC_FC_PER2PER_DSTPER	(0x7 << 21)	/* Periph-to-Periph (Dst Peripheral) */
 #define	ATC_SRC_ADDR_MODE_MASK	(0x3 << 24)
 #define		ATC_SRC_ADDR_MODE_INCR	(0x0 << 24)	/* Incrementing Mode */
 #define		ATC_SRC_ADDR_MODE_DECR	(0x1 << 24)	/* Decrementing Mode */
 #define		ATC_SRC_ADDR_MODE_FIXED	(0x2 << 24)	/* Fixed Mode */
 #define	ATC_DST_ADDR_MODE_MASK	(0x3 << 28)
 #define		ATC_DST_ADDR_MODE_INCR	(0x0 << 28)	/* Incrementing Mode */
 #define		ATC_DST_ADDR_MODE_DECR	(0x1 << 28)	/* Decrementing Mode */
 #define		ATC_DST_ADDR_MODE_FIXED	(0x2 << 28)	/* Fixed Mode */
 #define	ATC_IEN			(0x1 << 30)	/* BTC interrupt enable (active low) */
 #define	ATC_AUTO		(0x1 << 31)	/* Auto multiple buffer tx enable */

 /* Bitfields in CFG */
 /* are in at_hdmac.h */

 /* Bitfields in SPIP */
 #define	ATC_SPIP_HOLE(x)	(0xFFFFU & (x))
 #define	ATC_SPIP_BOUNDARY(x)	((0x3FF & (x)) << 16)

 /* Bitfields in DPIP */
 #define	ATC_DPIP_HOLE(x)	(0xFFFFU & (x))
 #define	ATC_DPIP_BOUNDARY(x)	((0x3FF & (x)) << 16)


 /*--  descriptors  -----------------------------------------------------*/

 /* LLI == Linked List Item; aka DMA buffer descriptor */
 struct at_lli {
 	/* values that are not changed by hardware */
 	dma_addr_t	saddr;
 	dma_addr_t	daddr;
 	/* value that may get written back: */
 	u32		ctrla;
 	/* more values that are not changed by hardware */
 	u32		ctrlb;
 	dma_addr_t	dscr;	/* chain to next lli */
 };

 /**
  * struct at_desc - software descriptor
  * @at_lli: hardware lli structure
  * @txd: support for the async_tx api
  * @desc_node: node on the channed descriptors list
  * @len: descriptor byte count
  * @tx_width: transfer width
  * @total_len: total transaction byte count
  */
 struct at_desc {
 	/* FIRST values the hardware uses */
 	struct at_lli			lli;

 	/* THEN values for driver housekeeping */
 	struct list_head		tx_list;
 	struct dma_async_tx_descriptor	txd;
 	struct list_head		desc_node;
 	size_t				len;
 	u32				tx_width;
 	size_t				total_len;

 	/* Interleaved data */
 	size_t				boundary;
 	size_t				dst_hole;
 	size_t				src_hole;
 };

 static inline struct at_desc *
 txd_to_at_desc(struct dma_async_tx_descriptor *txd)
 {
 	return container_of(txd, struct at_desc, txd);
 }


 /*--  Channels  --------------------------------------------------------*/

 /**
  * atc_status - information bits stored in channel status flag
  *
  * Manipulated with atomic operations.
  */
 enum atc_status {
 	ATC_IS_ERROR = 0,
 	ATC_IS_PAUSED = 1,
 	ATC_IS_CYCLIC = 24,
 };

 /**
  * struct at_dma_chan - internal representation of an Atmel HDMAC channel
  * @chan_common: common dmaengine channel object members
  * @device: parent device
  * @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)
  * @tasklet: bottom half to finish transaction work
  * @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
  * @lock: serializes enqueue/dequeue operations to descriptors lists
  * @active_list: list of descriptors dmaengine is being running on
  * @queue: list of descriptors ready to be submitted to engine
  * @free_list: list of descriptors usable by the channel
  * @descs_allocated: records the actual size of the descriptor pool
  */
 struct at_dma_chan {
 	struct dma_chan		chan_common;
 	struct at_dma		*device;
 	void __iomem		*ch_regs;
 	u8			mask;
 	u8			per_if;
 	u8			mem_if;
 	unsigned long		status;
 	struct tasklet_struct	tasklet;
 	u32			save_cfg;
 	u32			save_dscr;
 	struct dma_slave_config dma_sconfig;

 	spinlock_t		lock;

 	/* these other elements are all protected by lock */
 	struct list_head	active_list;
 	struct list_head	queue;
 	struct list_head	free_list;
 	unsigned int		descs_allocated;
 };

 #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)

 static inline struct at_dma_chan *to_at_dma_chan(struct dma_chan *dchan)
 {
 	return container_of(dchan, struct at_dma_chan, chan_common);
 }

 /*
  * 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
  * @chan_common: common 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
  * @dma_desc_pool: base of DMA descriptor region (DMA address)
  * @chan: channels table to store at_dma_chan structures
  */
 struct at_dma {
 	struct dma_device	dma_common;
 	void __iomem		*regs;
 	struct clk		*clk;
 	u32			save_imr;

 	u8			all_chan_mask;

 	struct dma_pool		*dma_desc_pool;
 	/* AT THE END channels table */
 	struct at_dma_chan	chan[0];
 };

 #define	dma_readl(atdma, name) \
 	__raw_readl((atdma)->regs + AT_DMA_##name)
 #define	dma_writel(atdma, name, val) \
 	__raw_writel((val), (atdma)->regs + AT_DMA_##name)

 static inline struct at_dma *to_at_dma(struct dma_device *ddev)
 {
 	return container_of(ddev, struct at_dma, dma_common);
 }


 /*--  Helper functions  ------------------------------------------------*/

 static struct device *chan2dev(struct dma_chan *chan)
 {
 	return &chan->dev->device;
 }

 #if defined(VERBOSE_DEBUG)
 static void vdbg_dump_regs(struct at_dma_chan *atchan)
 {
 	struct at_dma	*atdma = to_at_dma(atchan->chan_common.device);

 	dev_err(chan2dev(&atchan->chan_common),
 		"  channel %d : imr = 0x%x, chsr = 0x%x\n",
 		atchan->chan_common.chan_id,
 		dma_readl(atdma, EBCIMR),
 		dma_readl(atdma, CHSR));

 	dev_err(chan2dev(&atchan->chan_common),
 		"  channel: s0x%x d0x%x ctrl0x%x:0x%x cfg0x%x l0x%x\n",
 		channel_readl(atchan, SADDR),
 		channel_readl(atchan, DADDR),
 		channel_readl(atchan, CTRLA),
 		channel_readl(atchan, CTRLB),
 		channel_readl(atchan, CFG),
 		channel_readl(atchan, DSCR));
 }
 #else
 static void vdbg_dump_regs(struct at_dma_chan *atchan) {}
 #endif

 static void atc_dump_lli(struct at_dma_chan *atchan, struct at_lli *lli)
 {
 	dev_crit(chan2dev(&atchan->chan_common),
 		 "  desc: s0x%x d0x%x ctrl0x%x:0x%x l0x%x\n",
 		 lli->saddr, lli->daddr,
 		 lli->ctrla, lli->ctrlb, lli->dscr);
 }


 static void atc_setup_irq(struct at_dma *atdma, int chan_id, int on)
 {
 	u32 ebci;

 	/* enable interrupts on buffer transfer completion & error */
 	ebci =    AT_DMA_BTC(chan_id)
 		| AT_DMA_ERR(chan_id);
 	if (on)
 		dma_writel(atdma, EBCIER, ebci);
 	else
 		dma_writel(atdma, EBCIDR, ebci);
 }

 static void atc_enable_chan_irq(struct at_dma *atdma, int chan_id)
 {
 	atc_setup_irq(atdma, chan_id, 1);
 }

 static void atc_disable_chan_irq(struct at_dma *atdma, int chan_id)
 {
 	atc_setup_irq(atdma, chan_id, 0);
 }


 /**
  * atc_chan_is_enabled - test if given channel is enabled
  * @atchan: channel we want to test status
  */
 static inline int atc_chan_is_enabled(struct at_dma_chan *atchan)
 {
 	struct at_dma	*atdma = to_at_dma(atchan->chan_common.device);

 	return !!(dma_readl(atdma, CHSR) & atchan->mask);
 }

 /**
  * atc_chan_is_paused - test channel pause/resume status
  * @atchan: channel we want to test status
  */
 static inline int atc_chan_is_paused(struct at_dma_chan *atchan)
 {
 	return test_bit(ATC_IS_PAUSED, &atchan->status);
 }

 /**
  * atc_chan_is_cyclic - test if given channel has cyclic property set
  * @atchan: channel we want to test status
  */
 static inline int atc_chan_is_cyclic(struct at_dma_chan *atchan)
 {
 	return test_bit(ATC_IS_CYCLIC, &atchan->status);
 }

 /**
  * set_desc_eol - set end-of-link to descriptor so it will end transfer
  * @desc: descriptor, signle or at the end of a chain, to end chain on
  */
 static void set_desc_eol(struct at_desc *desc)
 {
 	u32 ctrlb = desc->lli.ctrlb;

 	ctrlb &= ~ATC_IEN;
 	ctrlb |= ATC_SRC_DSCR_DIS | ATC_DST_DSCR_DIS;

 	desc->lli.ctrlb = ctrlb;
 	desc->lli.dscr = 0;
 }

 #endif /* AT_HDMAC_REGS_H */
	/*
	* Header file for the Atmel AHB DMA Controller driver
	*
	* Copyright (C) 2008 Atmel Corporation
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*/
	#ifndef AT_HDMAC_REGS_H
	#define AT_HDMAC_REGS_H

	#include <linux/platform_data/dma-atmel.h>

	#define AT_DMA_MAX_NR_CHANNELS 8


	#define AT_DMA_GCFG 0x00 /* Global Configuration Register */
	#define AT_DMA_IF_BIGEND(i) (0x1 << (i)) /* AHB-Lite Interface i in Big-endian mode */
	#define AT_DMA_ARB_CFG (0x1 << 4) /* Arbiter mode. */
	#define AT_DMA_ARB_CFG_FIXED (0x0 << 4)
	#define AT_DMA_ARB_CFG_ROUND_ROBIN (0x1 << 4)

	#define AT_DMA_EN 0x04 /* Controller Enable Register */
	#define AT_DMA_ENABLE (0x1 << 0)

	#define AT_DMA_SREQ 0x08 /* Software Single Request Register */
	#define AT_DMA_SSREQ(x) (0x1 << ((x) << 1)) /* Request a source single transfer on channel x */
	#define AT_DMA_DSREQ(x) (0x1 << (1 + ((x) << 1))) /* Request a destination single transfer on channel x */

	#define AT_DMA_CREQ 0x0C /* Software Chunk Transfer Request Register */
	#define AT_DMA_SCREQ(x) (0x1 << ((x) << 1)) /* Request a source chunk transfer on channel x */
	#define AT_DMA_DCREQ(x) (0x1 << (1 + ((x) << 1))) /* Request a destination chunk transfer on channel x */

	#define AT_DMA_LAST 0x10 /* Software Last Transfer Flag Register */
	#define AT_DMA_SLAST(x) (0x1 << ((x) << 1)) /* This src rq is last tx of buffer on channel x */
	#define AT_DMA_DLAST(x) (0x1 << (1 + ((x) << 1))) /* This dst rq is last tx of buffer on channel x */

	#define AT_DMA_SYNC 0x14 /* Request Synchronization Register */
	#define AT_DMA_SYR(h) (0x1 << (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) (0x1 << (x))
	#define AT_DMA_CBTC(x) (0x1 << (AT_DMA_CBTC_OFFSET + (x)))
	#define AT_DMA_ERR(x) (0x1 << (AT_DMA_ERR_OFFSET + (x)))

	#define AT_DMA_CHER 0x28 /* Channel Handler Enable Register */
	#define AT_DMA_ENA(x) (0x1 << (x))
	#define AT_DMA_SUSP(x) (0x1 << ( 8 + (x)))
	#define AT_DMA_KEEP(x) (0x1 << (24 + (x)))

	#define AT_DMA_CHDR 0x2C /* Channel Handler Disable Register */
	#define AT_DMA_DIS(x) (0x1 << (x))
	#define AT_DMA_RES(x) (0x1 << ( 8 + (x)))

	#define AT_DMA_CHSR 0x30 /* Channel Handler Status Register */
	#define AT_DMA_EMPT(x) (0x1 << (16 + (x)))
	#define AT_DMA_STAL(x) (0x1 << (24 + (x)))


	#define AT_DMA_CH_REGS_BASE 0x3C /* Channel registers base address */
	#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(i) (0x3 & (i)) /* Dsc feched via AHB-Lite Interface i */

	/* Bitfields in CTRLA */
	#define ATC_BTSIZE_MAX 0xFFFFUL /* Maximum Buffer Transfer Size */
	#define ATC_BTSIZE(x) (ATC_BTSIZE_MAX & (x)) /* Buffer Transfer Size */
	#define ATC_SCSIZE_MASK (0x7 << 16) /* Source Chunk Transfer Size */
	#define ATC_SCSIZE(x) (ATC_SCSIZE_MASK & ((x) << 16))
	#define ATC_SCSIZE_1 (0x0 << 16)
	#define ATC_SCSIZE_4 (0x1 << 16)
	#define ATC_SCSIZE_8 (0x2 << 16)
	#define ATC_SCSIZE_16 (0x3 << 16)
	#define ATC_SCSIZE_32 (0x4 << 16)
	#define ATC_SCSIZE_64 (0x5 << 16)
	#define ATC_SCSIZE_128 (0x6 << 16)
	#define ATC_SCSIZE_256 (0x7 << 16)
	#define ATC_DCSIZE_MASK (0x7 << 20) /* Destination Chunk Transfer Size */
	#define ATC_DCSIZE(x) (ATC_DCSIZE_MASK & ((x) << 20))
	#define ATC_DCSIZE_1 (0x0 << 20)
	#define ATC_DCSIZE_4 (0x1 << 20)
	#define ATC_DCSIZE_8 (0x2 << 20)
	#define ATC_DCSIZE_16 (0x3 << 20)
	#define ATC_DCSIZE_32 (0x4 << 20)
	#define ATC_DCSIZE_64 (0x5 << 20)
	#define ATC_DCSIZE_128 (0x6 << 20)
	#define ATC_DCSIZE_256 (0x7 << 20)
	#define ATC_SRC_WIDTH_MASK (0x3 << 24) /* Source Single Transfer Size */
	#define ATC_SRC_WIDTH(x) ((x) << 24)
	#define ATC_SRC_WIDTH_BYTE (0x0 << 24)
	#define ATC_SRC_WIDTH_HALFWORD (0x1 << 24)
	#define ATC_SRC_WIDTH_WORD (0x2 << 24)
	#define ATC_DST_WIDTH_MASK (0x3 << 28) /* Destination Single Transfer Size */
	#define ATC_DST_WIDTH(x) ((x) << 28)
	#define ATC_DST_WIDTH_BYTE (0x0 << 28)
	#define ATC_DST_WIDTH_HALFWORD (0x1 << 28)
	#define ATC_DST_WIDTH_WORD (0x2 << 28)
	#define ATC_DONE (0x1 << 31) /* Tx Done (only written back in descriptor) */

	/* Bitfields in CTRLB */
	#define ATC_SIF(i) (0x3 & (i)) /* Src tx done via AHB-Lite Interface i */
	#define ATC_DIF(i) ((0x3 & (i)) << 4) /* Dst tx done via AHB-Lite Interface i */
	/* Specify AHB interfaces */
	#define AT_DMA_MEM_IF 0 /* interface 0 as memory interface */
	#define AT_DMA_PER_IF 1 /* interface 1 as peripheral interface */

	#define ATC_SRC_PIP (0x1 << 8) /* Source Picture-in-Picture enabled */
	#define ATC_DST_PIP (0x1 << 12) /* Destination Picture-in-Picture enabled */
	#define ATC_SRC_DSCR_DIS (0x1 << 16) /* Src Descriptor fetch disable */
	#define ATC_DST_DSCR_DIS (0x1 << 20) /* Dst Descriptor fetch disable */
	#define ATC_FC_MASK (0x7 << 21) /* Choose Flow Controller */
	#define ATC_FC_MEM2MEM (0x0 << 21) /* Mem-to-Mem (DMA) */
	#define ATC_FC_MEM2PER (0x1 << 21) /* Mem-to-Periph (DMA) */
	#define ATC_FC_PER2MEM (0x2 << 21) /* Periph-to-Mem (DMA) */
	#define ATC_FC_PER2PER (0x3 << 21) /* Periph-to-Periph (DMA) */
	#define ATC_FC_PER2MEM_PER (0x4 << 21) /* Periph-to-Mem (Peripheral) */
	#define ATC_FC_MEM2PER_PER (0x5 << 21) /* Mem-to-Periph (Peripheral) */
	#define ATC_FC_PER2PER_SRCPER (0x6 << 21) /* Periph-to-Periph (Src Peripheral) */
	#define ATC_FC_PER2PER_DSTPER (0x7 << 21) /* Periph-to-Periph (Dst Peripheral) */
	#define ATC_SRC_ADDR_MODE_MASK (0x3 << 24)
	#define ATC_SRC_ADDR_MODE_INCR (0x0 << 24) /* Incrementing Mode */
	#define ATC_SRC_ADDR_MODE_DECR (0x1 << 24) /* Decrementing Mode */
	#define ATC_SRC_ADDR_MODE_FIXED (0x2 << 24) /* Fixed Mode */
	#define ATC_DST_ADDR_MODE_MASK (0x3 << 28)
	#define ATC_DST_ADDR_MODE_INCR (0x0 << 28) /* Incrementing Mode */
	#define ATC_DST_ADDR_MODE_DECR (0x1 << 28) /* Decrementing Mode */
	#define ATC_DST_ADDR_MODE_FIXED (0x2 << 28) /* Fixed Mode */
	#define ATC_IEN (0x1 << 30) /* BTC interrupt enable (active low) */
	#define ATC_AUTO (0x1 << 31) /* Auto multiple buffer tx enable */

	/* Bitfields in CFG */
	/* are in at_hdmac.h */

	/* Bitfields in SPIP */
	#define ATC_SPIP_HOLE(x) (0xFFFFU & (x))
	#define ATC_SPIP_BOUNDARY(x) ((0x3FF & (x)) << 16)

	/* Bitfields in DPIP */
	#define ATC_DPIP_HOLE(x) (0xFFFFU & (x))
	#define ATC_DPIP_BOUNDARY(x) ((0x3FF & (x)) << 16)


	/-- descriptors -----------------------------------------------------/

	/* LLI == Linked List Item; aka DMA buffer descriptor */
	struct at_lli {
	/* values that are not changed by hardware */
	dma_addr_t saddr;
	dma_addr_t daddr;
	/* value that may get written back: */
	u32 ctrla;
	/* more values that are not changed by hardware */
	u32 ctrlb;
	dma_addr_t dscr; /* chain to next lli */
	};

	/**
	* struct at_desc - software descriptor
	* @at_lli: hardware lli structure
	* @txd: support for the async_tx api
	* @desc_node: node on the channed descriptors list
	* @len: descriptor byte count
	* @tx_width: transfer width
	* @total_len: total transaction byte count
	*/
	struct at_desc {
	/* FIRST values the hardware uses */
	struct at_lli lli;

	/* THEN values for driver housekeeping */
	struct list_head tx_list;
	struct dma_async_tx_descriptor txd;
	struct list_head desc_node;
	size_t len;
	u32 tx_width;
	size_t total_len;

	/* Interleaved data */
	size_t boundary;
	size_t dst_hole;
	size_t src_hole;
	};

	static inline struct at_desc *
	txd_to_at_desc(struct dma_async_tx_descriptor *txd)
	{
	return container_of(txd, struct at_desc, txd);
	}


	/-- Channels --------------------------------------------------------/

	/**
	* atc_status - information bits stored in channel status flag
	*
	* Manipulated with atomic operations.
	*/
	enum atc_status {
	ATC_IS_ERROR = 0,
	ATC_IS_PAUSED = 1,
	ATC_IS_CYCLIC = 24,
	};

	/**
	* struct at_dma_chan - internal representation of an Atmel HDMAC channel
	* @chan_common: common dmaengine channel object members
	* @device: parent device
	* @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)
	* @tasklet: bottom half to finish transaction work
	* @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
	* @lock: serializes enqueue/dequeue operations to descriptors lists
	* @active_list: list of descriptors dmaengine is being running on
	* @queue: list of descriptors ready to be submitted to engine
	* @free_list: list of descriptors usable by the channel
	* @descs_allocated: records the actual size of the descriptor pool
	*/
	struct at_dma_chan {
	struct dma_chan chan_common;
	struct at_dma *device;
	void __iomem *ch_regs;
	u8 mask;
	u8 per_if;
	u8 mem_if;
	unsigned long status;
	struct tasklet_struct tasklet;
	u32 save_cfg;
	u32 save_dscr;
	struct dma_slave_config dma_sconfig;

	spinlock_t lock;

	/* these other elements are all protected by lock */
	struct list_head active_list;
	struct list_head queue;
	struct list_head free_list;
	unsigned int descs_allocated;
	};

	#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)

	static inline struct at_dma_chan to_at_dma_chan(struct dma_chan dchan)
	{
	return container_of(dchan, struct at_dma_chan, chan_common);
	}

	/*
	* 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
	* @chan_common: common 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
	* @dma_desc_pool: base of DMA descriptor region (DMA address)
	* @chan: channels table to store at_dma_chan structures
	*/
	struct at_dma {
	struct dma_device dma_common;
	void __iomem *regs;
	struct clk *clk;
	u32 save_imr;

	u8 all_chan_mask;

	struct dma_pool *dma_desc_pool;
	/* AT THE END channels table */
	struct at_dma_chan chan[0];
	};

	#define dma_readl(atdma, name) \
	__raw_readl((atdma)->regs + AT_DMA_##name)
	#define dma_writel(atdma, name, val) \
	__raw_writel((val), (atdma)->regs + AT_DMA_##name)

	static inline struct at_dma to_at_dma(struct dma_device ddev)
	{
	return container_of(ddev, struct at_dma, dma_common);
	}


	/-- Helper functions ------------------------------------------------/

	static struct device chan2dev(struct dma_chan chan)
	{
	return &chan->dev->device;
	}

	#if defined(VERBOSE_DEBUG)
	static void vdbg_dump_regs(struct at_dma_chan *atchan)
	{
	struct at_dma *atdma = to_at_dma(atchan->chan_common.device);

	dev_err(chan2dev(&atchan->chan_common),
	" channel %d : imr = 0x%x, chsr = 0x%x\n",
	atchan->chan_common.chan_id,
	dma_readl(atdma, EBCIMR),
	dma_readl(atdma, CHSR));

	dev_err(chan2dev(&atchan->chan_common),
	" channel: s0x%x d0x%x ctrl0x%x:0x%x cfg0x%x l0x%x\n",
	channel_readl(atchan, SADDR),
	channel_readl(atchan, DADDR),
	channel_readl(atchan, CTRLA),
	channel_readl(atchan, CTRLB),
	channel_readl(atchan, CFG),
	channel_readl(atchan, DSCR));
	}
	#else
	static void vdbg_dump_regs(struct at_dma_chan *atchan) {}
	#endif

	static void atc_dump_lli(struct at_dma_chan atchan, struct at_lli lli)
	{
	dev_crit(chan2dev(&atchan->chan_common),
	" desc: s0x%x d0x%x ctrl0x%x:0x%x l0x%x\n",
	lli->saddr, lli->daddr,
	lli->ctrla, lli->ctrlb, lli->dscr);
	}


	static void atc_setup_irq(struct at_dma *atdma, int chan_id, int on)
	{
	u32 ebci;

	/* enable interrupts on buffer transfer completion & error */
	ebci = AT_DMA_BTC(chan_id)
	\| AT_DMA_ERR(chan_id);
	if (on)
	dma_writel(atdma, EBCIER, ebci);
	else
	dma_writel(atdma, EBCIDR, ebci);
	}

	static void atc_enable_chan_irq(struct at_dma *atdma, int chan_id)
	{
	atc_setup_irq(atdma, chan_id, 1);
	}

	static void atc_disable_chan_irq(struct at_dma *atdma, int chan_id)
	{
	atc_setup_irq(atdma, chan_id, 0);
	}


	/**
	* atc_chan_is_enabled - test if given channel is enabled
	* @atchan: channel we want to test status
	*/
	static inline int atc_chan_is_enabled(struct at_dma_chan *atchan)
	{
	struct at_dma *atdma = to_at_dma(atchan->chan_common.device);

	return !!(dma_readl(atdma, CHSR) & atchan->mask);
	}

	/**
	* atc_chan_is_paused - test channel pause/resume status
	* @atchan: channel we want to test status
	*/
	static inline int atc_chan_is_paused(struct at_dma_chan *atchan)
	{
	return test_bit(ATC_IS_PAUSED, &atchan->status);
	}

	/**
	* atc_chan_is_cyclic - test if given channel has cyclic property set
	* @atchan: channel we want to test status
	*/
	static inline int atc_chan_is_cyclic(struct at_dma_chan *atchan)
	{
	return test_bit(ATC_IS_CYCLIC, &atchan->status);
	}

	/**
	* set_desc_eol - set end-of-link to descriptor so it will end transfer
	* @desc: descriptor, signle or at the end of a chain, to end chain on
	*/
	static void set_desc_eol(struct at_desc *desc)
	{
	u32 ctrlb = desc->lli.ctrlb;

	ctrlb &= ~ATC_IEN;
	ctrlb \|= ATC_SRC_DSCR_DIS \| ATC_DST_DSCR_DIS;

	desc->lli.ctrlb = ctrlb;
	desc->lli.dscr = 0;
	}

	#endif /* AT_HDMAC_REGS_H */