rt-thread/bsp/dm365/platform/dma.c

/*
 * File      : dma.c
 * This file is part of RT-Thread RTOS
 * COPYRIGHT (C) 2006, RT-Thread Development Team
 *
 *  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.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Change Logs:
 * Date           Author		Notes
 * 2010-11-13     weety		first version
 */


#include <edma.h>

/* Offsets matching "struct edmacc_param" */
#define PARM_OPT		0x00
#define PARM_SRC		0x04
#define PARM_A_B_CNT		0x08
#define PARM_DST		0x0c
#define PARM_SRC_DST_BIDX	0x10
#define PARM_LINK_BCNTRLD	0x14
#define PARM_SRC_DST_CIDX	0x18
#define PARM_CCNT		0x1c

#define PARM_SIZE		0x20

/* Offsets for EDMA CC global channel registers and their shadows */
#define SH_ER		0x00	/* 64 bits */
#define SH_ECR		0x08	/* 64 bits */
#define SH_ESR		0x10	/* 64 bits */
#define SH_CER		0x18	/* 64 bits */
#define SH_EER		0x20	/* 64 bits */
#define SH_EECR		0x28	/* 64 bits */
#define SH_EESR		0x30	/* 64 bits */
#define SH_SER		0x38	/* 64 bits */
#define SH_SECR		0x40	/* 64 bits */
#define SH_IER		0x50	/* 64 bits */
#define SH_IECR		0x58	/* 64 bits */
#define SH_IESR		0x60	/* 64 bits */
#define SH_IPR		0x68	/* 64 bits */
#define SH_ICR		0x70	/* 64 bits */
#define SH_IEVAL	0x78
#define SH_QER		0x80
#define SH_QEER		0x84
#define SH_QEECR	0x88
#define SH_QEESR	0x8c
#define SH_QSER		0x90
#define SH_QSECR	0x94
#define SH_SIZE		0x200

/* Offsets for EDMA CC global registers */
#define EDMA_REV	0x0000
#define EDMA_CCCFG	0x0004
#define EDMA_QCHMAP	0x0200	/* 8 registers */
#define EDMA_DMAQNUM	0x0240	/* 8 registers (4 on OMAP-L1xx) */
#define EDMA_QDMAQNUM	0x0260
#define EDMA_QUETCMAP	0x0280
#define EDMA_QUEPRI	0x0284
#define EDMA_EMR	0x0300	/* 64 bits */
#define EDMA_EMCR	0x0308	/* 64 bits */
#define EDMA_QEMR	0x0310
#define EDMA_QEMCR	0x0314
#define EDMA_CCERR	0x0318
#define EDMA_CCERRCLR	0x031c
#define EDMA_EEVAL	0x0320
#define EDMA_DRAE	0x0340	/* 4 x 64 bits*/
#define EDMA_QRAE	0x0380	/* 4 registers */
#define EDMA_QUEEVTENTRY	0x0400	/* 2 x 16 registers */
#define EDMA_QSTAT	0x0600	/* 2 registers */
#define EDMA_QWMTHRA	0x0620
#define EDMA_QWMTHRB	0x0624
#define EDMA_CCSTAT	0x0640

#define EDMA_M		0x1000	/* global channel registers */
#define EDMA_ECR	0x1008
#define EDMA_ECRH	0x100C
#define EDMA_SHADOW0	0x2000	/* 4 regions shadowing global channels */
#define EDMA_PARM	0x4000	/* 128 param entries */

#define PARM_OFFSET(param_no)	(EDMA_PARM + ((param_no) << 5))

#define EDMA_DCHMAP	0x0100  /* 64 registers */
#define CHMAP_EXIST	BIT(24)

#define EDMA_MAX_DMACH           64
#define EDMA_MAX_PARAMENTRY     512

#define EDMA_CC0_BASE_REG	0x01c00000
#define EDMA_TC0_BASE_REG	0x01c10000
#define EDMA_TC1_BASE_REG	0x01c10400
#define EDMA_TC2_BASE_REG	0x01c10800
#define EDMA_TC3_BASE_REG	0x01c10c00

#define min_t(type, x, y) ({			\
	type __min1 = (x);			\
	type __min2 = (y);			\
	__min1 < __min2 ? __min1: __min2; })



/*****************************************************************************/

static void volatile *edmacc_regs_base[EDMA_MAX_CC];

static inline unsigned int edma_read(unsigned ctlr, int offset)
{
	return (unsigned int)davinci_readl(edmacc_regs_base[ctlr] + offset);
}

static inline void edma_write(unsigned ctlr, int offset, int val)
{
	davinci_writel(val, edmacc_regs_base[ctlr] + offset);
}
static inline void edma_modify(unsigned ctlr, int offset, unsigned and,
		unsigned or)
{
	unsigned val = edma_read(ctlr, offset);
	val &= and;
	val |= or;
	edma_write(ctlr, offset, val);
}
static inline void edma_and(unsigned ctlr, int offset, unsigned and)
{
	unsigned val = edma_read(ctlr, offset);
	val &= and;
	edma_write(ctlr, offset, val);
}
static inline void edma_or(unsigned ctlr, int offset, unsigned or)
{
	unsigned val = edma_read(ctlr, offset);
	val |= or;
	edma_write(ctlr, offset, val);
}
static inline unsigned int edma_read_array(unsigned ctlr, int offset, int i)
{
	return edma_read(ctlr, offset + (i << 2));
}
static inline void edma_write_array(unsigned ctlr, int offset, int i,
		unsigned val)
{
	edma_write(ctlr, offset + (i << 2), val);
}
static inline void edma_modify_array(unsigned ctlr, int offset, int i,
		unsigned and, unsigned or)
{
	edma_modify(ctlr, offset + (i << 2), and, or);
}
static inline void edma_or_array(unsigned ctlr, int offset, int i, unsigned or)
{
	edma_or(ctlr, offset + (i << 2), or);
}
static inline void edma_or_array2(unsigned ctlr, int offset, int i, int j,
		unsigned or)
{
	edma_or(ctlr, offset + ((i*2 + j) << 2), or);
}
static inline void edma_write_array2(unsigned ctlr, int offset, int i, int j,
		unsigned val)
{
	edma_write(ctlr, offset + ((i*2 + j) << 2), val);
}
static inline unsigned int edma_shadow0_read(unsigned ctlr, int offset)
{
	return edma_read(ctlr, EDMA_SHADOW0 + offset);
}
static inline unsigned int edma_shadow0_read_array(unsigned ctlr, int offset,
		int i)
{
	return edma_read(ctlr, EDMA_SHADOW0 + offset + (i << 2));
}
static inline void edma_shadow0_write(unsigned ctlr, int offset, unsigned val)
{
	edma_write(ctlr, EDMA_SHADOW0 + offset, val);
}
static inline void edma_shadow0_write_array(unsigned ctlr, int offset, int i,
		unsigned val)
{
	edma_write(ctlr, EDMA_SHADOW0 + offset + (i << 2), val);
}
static inline unsigned int edma_parm_read(unsigned ctlr, int offset,
		int param_no)
{
	return edma_read(ctlr, EDMA_PARM + offset + (param_no << 5));
}
static inline void edma_parm_write(unsigned ctlr, int offset, int param_no,
		unsigned val)
{
	edma_write(ctlr, EDMA_PARM + offset + (param_no << 5), val);
}
static inline void edma_parm_modify(unsigned ctlr, int offset, int param_no,
		unsigned and, unsigned or)
{
	edma_modify(ctlr, EDMA_PARM + offset + (param_no << 5), and, or);
}
static inline void edma_parm_and(unsigned ctlr, int offset, int param_no,
		unsigned and)
{
	edma_and(ctlr, EDMA_PARM + offset + (param_no << 5), and);
}
static inline void edma_parm_or(unsigned ctlr, int offset, int param_no,
		unsigned or)
{
	edma_or(ctlr, EDMA_PARM + offset + (param_no << 5), or);
}
#if 0
static inline void set_bits(int offset, int len, unsigned long *p)
{
	for (; len > 0; len--)
		set_bit(offset + (len - 1), p);
}

static inline void clear_bits(int offset, int len, unsigned long *p)
{
	for (; len > 0; len--)
		clear_bit(offset + (len - 1), p);
}
#endif
/*****************************************************************************/

#define BIT(nr)			(1UL << (nr))
#define BITS_PER_LONG 32
#define BIT_MASK(nr)		(1UL << ((nr) % BITS_PER_LONG))
#define BIT_WORD(nr)		((nr) / BITS_PER_LONG)
#define BITS_PER_BYTE		8
#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))

#define BITS_TO_LONGS(nr)	DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))

#define DECLARE_BITMAP(name,bits) \
	unsigned long name[BITS_TO_LONGS(bits)]

/**
 * test_bit - Determine whether a bit is set
 * @nr: bit number to test
 * @addr: Address to start counting from
 */
static inline int test_bit(int nr, const volatile unsigned long *addr)
{
	return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
}

static inline void clear_bit(int nr, volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
	rt_base_t level;

	level = rt_hw_interrupt_disable();
	*p &= ~mask;
	rt_hw_interrupt_enable(level);
}

static inline int test_and_set_bit(int nr, volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
	unsigned long old;
	rt_base_t level;

	level = rt_hw_interrupt_disable();
	old = *p;
	*p = old | mask;
	rt_hw_interrupt_enable(level);

	return (old & mask) != 0;
}

static inline void set_bit(int nr, volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
	rt_base_t level;

	level = rt_hw_interrupt_disable();
	*p  |= mask;
	rt_hw_interrupt_enable(level);
}

/*
 * Little endian assembly bitops.  nr = 0 -> byte 0 bit 0.
 */
extern int _find_first_zero_bit_le(const void * p, unsigned size);
extern int _find_next_zero_bit_le(const void * p, int size, int offset);
extern int _find_first_bit_le(const unsigned long *p, unsigned size);
extern int _find_next_bit_le(const unsigned long *p, int size, int offset);

/*
 * These are the little endian, atomic definitions.
 */
#define find_first_zero_bit(p,sz)	_find_first_zero_bit_le(p,sz)
#define find_next_zero_bit(p,sz,off)	_find_next_zero_bit_le(p,sz,off)
#define find_first_bit(p,sz)		_find_first_bit_le(p,sz)
#define find_next_bit(p,sz,off)		_find_next_bit_le(p,sz,off)



/* actual number of DMA channels and slots on this silicon */
struct edma {
	/* how many dma resources of each type */
	unsigned	num_channels;
	unsigned	num_region;
	unsigned	num_slots;
	unsigned	num_tc;
	unsigned	num_cc;
	enum dma_event_q 	default_queue;

	/* list of channels with no even trigger; terminated by "-1" */
	const rt_int8_t	*noevent;

	/* The edma_inuse bit for each PaRAM slot is clear unless the
	 * channel is in use ... by ARM or DSP, for QDMA, or whatever.
	 */
	DECLARE_BITMAP(edma_inuse, EDMA_MAX_PARAMENTRY);

	/* The edma_unused bit for each channel is clear unless
	 * it is not being used on this platform. It uses a bit
	 * of SOC-specific initialization code.
	 */
	DECLARE_BITMAP(edma_unused, EDMA_MAX_DMACH);

	unsigned	irq_res_start;
	unsigned	irq_res_end;

	struct dma_interrupt_data {
		void (*callback)(unsigned channel, unsigned short ch_status,
				void *data);
		void *data;
	} intr_data[EDMA_MAX_DMACH];
};

static struct edma *edma_cc[EDMA_MAX_CC];
static int arch_num_cc;

/* dummy param set used to (re)initialize parameter RAM slots */
static const struct edmacc_param dummy_paramset = {
	.link_bcntrld = 0xffff,
	.ccnt = 1,
};

/*****************************************************************************/

static void map_dmach_queue(unsigned ctlr, unsigned ch_no,
		enum dma_event_q queue_no)
{
	int bit = (ch_no & 0x7) * 4;

	/* default to low priority queue */
	if (queue_no == EVENTQ_DEFAULT)
		queue_no = edma_cc[ctlr]->default_queue;

	queue_no &= 7;
	edma_modify_array(ctlr, EDMA_DMAQNUM, (ch_no >> 3),
			~(0x7 << bit), queue_no << bit);
}

static void map_queue_tc(unsigned ctlr, int queue_no, int tc_no)
{
	int bit = queue_no * 4;
	edma_modify(ctlr, EDMA_QUETCMAP, ~(0x7 << bit), ((tc_no & 0x7) << bit));
}

static void assign_priority_to_queue(unsigned ctlr, int queue_no,
		int priority)
{
	int bit = queue_no * 4;
	edma_modify(ctlr, EDMA_QUEPRI, ~(0x7 << bit),
			((priority & 0x7) << bit));
}

/**
 * map_dmach_param - Maps channel number to param entry number
 *
 * This maps the dma channel number to param entry numberter. In
 * other words using the DMA channel mapping registers a param entry
 * can be mapped to any channel
 *
 * Callers are responsible for ensuring the channel mapping logic is
 * included in that particular EDMA variant (Eg : dm646x)
 *
 */
static void map_dmach_param(unsigned ctlr)
{
	int i;
	for (i = 0; i < EDMA_MAX_DMACH; i++)
		edma_write_array(ctlr, EDMA_DCHMAP , i , (i << 5));
}

static inline void
setup_dma_interrupt(unsigned lch,
	void (*callback)(unsigned channel, rt_uint16_t ch_status, void *data),
	void *data)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(lch);
	lch = EDMA_CHAN_SLOT(lch);

	if (!callback)
		edma_shadow0_write_array(ctlr, SH_IECR, lch >> 5,
				BIT(lch & 0x1f));

	edma_cc[ctlr]->intr_data[lch].callback = callback;
	edma_cc[ctlr]->intr_data[lch].data = data;

	if (callback) {
		edma_shadow0_write_array(ctlr, SH_ICR, lch >> 5,
				BIT(lch & 0x1f));
		edma_shadow0_write_array(ctlr, SH_IESR, lch >> 5,
				BIT(lch & 0x1f));
	}
}

static int irq2ctlr(int irq)
{
	if (irq >= edma_cc[0]->irq_res_start && irq <= edma_cc[0]->irq_res_end)
		return 0;
	else if (irq >= edma_cc[1]->irq_res_start &&
		irq <= edma_cc[1]->irq_res_end)
		return 1;

	return -1;
}

/******************************************************************************
 *
 * DMA interrupt handler
 *
 *****************************************************************************/
static void dma_irq_handler(int irq, void *data)
{
	int i;
	int ctlr;
	unsigned int cnt = 0;

	ctlr = irq2ctlr(irq);
	if (ctlr < 0)
		return ;

	edma_dbg("dma_irq_handler\n");

	if ((edma_shadow0_read_array(ctlr, SH_IPR, 0) == 0) &&
	    (edma_shadow0_read_array(ctlr, SH_IPR, 1) == 0))
		return ;

	while (1) {
		int j;
		if (edma_shadow0_read_array(ctlr, SH_IPR, 0) &
				edma_shadow0_read_array(ctlr, SH_IER, 0))
			j = 0;
		else if (edma_shadow0_read_array(ctlr, SH_IPR, 1) &
				edma_shadow0_read_array(ctlr, SH_IER, 1))
			j = 1;
		else
			break;
		edma_dbg("IPR%d %08x\n", j,
				edma_shadow0_read_array(ctlr, SH_IPR, j));
		for (i = 0; i < 32; i++) {
			int k = (j << 5) + i;
			if ((edma_shadow0_read_array(ctlr, SH_IPR, j) & BIT(i))
					&& (edma_shadow0_read_array(ctlr,
							SH_IER, j) & BIT(i))) {
				/* Clear the corresponding IPR bits */
				edma_shadow0_write_array(ctlr, SH_ICR, j,
							BIT(i));
				if (edma_cc[ctlr]->intr_data[k].callback)
					edma_cc[ctlr]->intr_data[k].callback(
						k, DMA_COMPLETE,
						edma_cc[ctlr]->intr_data[k].
						data);
			}
		}
		cnt++;
		if (cnt > 10)
			break;
	}
	edma_shadow0_write(ctlr, SH_IEVAL, 1);
	return ;
}

/******************************************************************************
 *
 * DMA error interrupt handler
 *
 *****************************************************************************/
static void dma_ccerr_handler(int irq, void *data)
{
	int i;
	int ctlr;
	unsigned int cnt = 0;

	ctlr = irq2ctlr(irq);
	if (ctlr < 0)
		return ;

	edma_dbg("dma_ccerr_handler\n");

	if ((edma_read_array(ctlr, EDMA_EMR, 0) == 0) &&
	    (edma_read_array(ctlr, EDMA_EMR, 1) == 0) &&
	    (edma_read(ctlr, EDMA_QEMR) == 0) &&
	    (edma_read(ctlr, EDMA_CCERR) == 0))
		return ;

	while (1) {
		int j = -1;
		if (edma_read_array(ctlr, EDMA_EMR, 0))
			j = 0;
		else if (edma_read_array(ctlr, EDMA_EMR, 1))
			j = 1;
		if (j >= 0) {
			edma_dbg("EMR%d %08x\n", j,
					edma_read_array(ctlr, EDMA_EMR, j));
			for (i = 0; i < 32; i++) {
				int k = (j << 5) + i;
				if (edma_read_array(ctlr, EDMA_EMR, j) &
							BIT(i)) {
					/* Clear the corresponding EMR bits */
					edma_write_array(ctlr, EDMA_EMCR, j,
							BIT(i));
					/* Clear any SER */
					edma_shadow0_write_array(ctlr, SH_SECR,
								j, BIT(i));
					if (edma_cc[ctlr]->intr_data[k].
								callback) {
						edma_cc[ctlr]->intr_data[k].
						callback(k,
						DMA_CC_ERROR,
						edma_cc[ctlr]->intr_data
						[k].data);
					}
				}
			}
		} else if (edma_read(ctlr, EDMA_QEMR)) {
			edma_dbg("QEMR %02x\n",
				edma_read(ctlr, EDMA_QEMR));
			for (i = 0; i < 8; i++) {
				if (edma_read(ctlr, EDMA_QEMR) & BIT(i)) {
					/* Clear the corresponding IPR bits */
					edma_write(ctlr, EDMA_QEMCR, BIT(i));
					edma_shadow0_write(ctlr, SH_QSECR,
								BIT(i));

					/* NOTE:  not reported!! */
				}
			}
		} else if (edma_read(ctlr, EDMA_CCERR)) {
			edma_dbg("CCERR %08x\n",
				edma_read(ctlr, EDMA_CCERR));
			/* FIXME:  CCERR.BIT(16) ignored!  much better
			 * to just write CCERRCLR with CCERR value...
			 */
			for (i = 0; i < 8; i++) {
				if (edma_read(ctlr, EDMA_CCERR) & BIT(i)) {
					/* Clear the corresponding IPR bits */
					edma_write(ctlr, EDMA_CCERRCLR, BIT(i));

					/* NOTE:  not reported!! */
				}
			}
		}
		if ((edma_read_array(ctlr, EDMA_EMR, 0) == 0) &&
		    (edma_read_array(ctlr, EDMA_EMR, 1) == 0) &&
		    (edma_read(ctlr, EDMA_QEMR) == 0) &&
		    (edma_read(ctlr, EDMA_CCERR) == 0))
			break;
		cnt++;
		if (cnt > 10)
			break;
	}
	edma_write(ctlr, EDMA_EEVAL, 1);
	return ;
}

/******************************************************************************
 *
 * Transfer controller error interrupt handlers
 *
 *****************************************************************************/

#define tc_errs_handled	RT_FALSE/* disabled as long as they're NOPs */

static void dma_tc0err_handler(int irq, void *data)
{
	edma_dbg("dma_tc0err_handler\n");
	return ;
}

static void dma_tc1err_handler(int irq, void *data)
{
	edma_dbg("dma_tc1err_handler\n");
	return ;
}

static int reserve_contiguous_slots(int ctlr, unsigned int id,
				     unsigned int num_slots,
				     unsigned int start_slot)
{
	int i, j;
	unsigned int count = num_slots;
	int stop_slot = start_slot;
	DECLARE_BITMAP(tmp_inuse, EDMA_MAX_PARAMENTRY);

	for (i = start_slot; i < edma_cc[ctlr]->num_slots; ++i) {
		j = EDMA_CHAN_SLOT(i);
		if (!test_and_set_bit(j, edma_cc[ctlr]->edma_inuse)) {
			/* Record our current beginning slot */
			if (count == num_slots)
				stop_slot = i;

			count--;
			set_bit(j, tmp_inuse);

			if (count == 0)
				break;
		} else {
			clear_bit(j, tmp_inuse);

			if (id == EDMA_CONT_PARAMS_FIXED_EXACT) {
				stop_slot = i;
				break;
			} else {
				count = num_slots;
			}
		}
	}

	/*
	 * We have to clear any bits that we set
	 * if we run out parameter RAM slots, i.e we do find a set
	 * of contiguous parameter RAM slots but do not find the exact number
	 * requested as we may reach the total number of parameter RAM slots
	 */
	if (i == edma_cc[ctlr]->num_slots)
		stop_slot = i;

	for (j = start_slot; j < stop_slot; j++)
		if (test_bit(j, tmp_inuse))
			clear_bit(j, edma_cc[ctlr]->edma_inuse);

	if (count)
		return -RT_EBUSY;

	for (j = i - num_slots + 1; j <= i; ++j)
		rt_memcpy((void *)(edmacc_regs_base[ctlr] + PARM_OFFSET(j)),
			&dummy_paramset, PARM_SIZE);

	return EDMA_CTLR_CHAN(ctlr, i - num_slots + 1);
}

#if 0
static int prepare_unused_channel_list(struct device *dev, void *data)
{
	struct platform_device *pdev = to_platform_device(dev);
	int i, ctlr;

	for (i = 0; i < pdev->num_resources; i++) {
		if ((pdev->resource[i].flags & IORESOURCE_DMA) &&
				(int)pdev->resource[i].start >= 0) {
			ctlr = EDMA_CTLR(pdev->resource[i].start);
			clear_bit(EDMA_CHAN_SLOT(pdev->resource[i].start),
					edma_cc[ctlr]->edma_unused);
		}
	}

	return 0;
}
#endif

/*-----------------------------------------------------------------------*/

static rt_bool_t unused_chan_list_done;

/* Resource alloc/free:  dma channels, parameter RAM slots */

/**
 * edma_alloc_channel - allocate DMA channel and paired parameter RAM
 * @channel: specific channel to allocate; negative for "any unmapped channel"
 * @callback: optional; to be issued on DMA completion or errors
 * @data: passed to callback
 * @eventq_no: an EVENTQ_* constant, used to choose which Transfer
 *	Controller (TC) executes requests using this channel.  Use
 *	EVENTQ_DEFAULT unless you really need a high priority queue.
 *
 * This allocates a DMA channel and its associated parameter RAM slot.
 * The parameter RAM is initialized to hold a dummy transfer.
 *
 * Normal use is to pass a specific channel number as @channel, to make
 * use of hardware events mapped to that channel.  When the channel will
 * be used only for software triggering or event chaining, channels not
 * mapped to hardware events (or mapped to unused events) are preferable.
 *
 * DMA transfers start from a channel using edma_start(), or by
 * chaining.  When the transfer described in that channel's parameter RAM
 * slot completes, that slot's data may be reloaded through a link.
 *
 * DMA errors are only reported to the @callback associated with the
 * channel driving that transfer, but transfer completion callbacks can
 * be sent to another channel under control of the TCC field in
 * the option word of the transfer's parameter RAM set.  Drivers must not
 * use DMA transfer completion callbacks for channels they did not allocate.
 * (The same applies to TCC codes used in transfer chaining.)
 *
 * Returns the number of the channel, else negative errno.
 */
int edma_alloc_channel(int channel,
		void (*callback)(unsigned channel, rt_uint16_t ch_status, void *data),
		void *data,
		enum dma_event_q eventq_no)
{
	unsigned i, done = 0, ctlr = 0;
	int ret = 0;
#if 0
	if (!unused_chan_list_done) {
		/*
		 * Scan all the platform devices to find out the EDMA channels
		 * used and clear them in the unused list, making the rest
		 * available for ARM usage.
		 */
		ret = bus_for_each_dev(&platform_bus_type, NULL, NULL,
				prepare_unused_channel_list);
		if (ret < 0)
			return ret;

		unused_chan_list_done = true;
	}
#endif

	if (channel >= 0) {
		ctlr = EDMA_CTLR(channel);
		channel = EDMA_CHAN_SLOT(channel);
 		clear_bit(channel, edma_cc[ctlr]->edma_unused);
	}

	if (channel < 0) {
		for (i = 0; i < arch_num_cc; i++) {
			channel = 0;
			for (;;) {
				channel = find_next_bit(edma_cc[i]->edma_unused,
						edma_cc[i]->num_channels,
						channel);
				if (channel == edma_cc[i]->num_channels)
					break;
				if (!test_and_set_bit(channel,
						edma_cc[i]->edma_inuse)) {
					done = 1;
					ctlr = i;
					break;
				}
				channel++;
			}
			if (done)
				break;
		}
		if (!done)
			return -RT_ENOMEM;
	} else if (channel >= edma_cc[ctlr]->num_channels) {
		return -RT_ERROR;
	} else if (test_and_set_bit(channel, edma_cc[ctlr]->edma_inuse)) {
		return -RT_EBUSY;
	}

	/* ensure access through shadow region 0 */
	edma_or_array2(ctlr, EDMA_DRAE, 0, channel >> 5, BIT(channel & 0x1f));

	/* ensure no events are pending */
	edma_stop(EDMA_CTLR_CHAN(ctlr, channel));
	rt_memcpy((void *)(edmacc_regs_base[ctlr] + PARM_OFFSET(channel)),
			&dummy_paramset, PARM_SIZE);

	if (callback)
		setup_dma_interrupt(EDMA_CTLR_CHAN(ctlr, channel),
					callback, data);

	map_dmach_queue(ctlr, channel, eventq_no);

	return EDMA_CTLR_CHAN(ctlr, channel);
}


/**
 * edma_free_channel - deallocate DMA channel
 * @channel: dma channel returned from edma_alloc_channel()
 *
 * This deallocates the DMA channel and associated parameter RAM slot
 * allocated by edma_alloc_channel().
 *
 * Callers are responsible for ensuring the channel is inactive, and
 * will not be reactivated by linking, chaining, or software calls to
 * edma_start().
 */
void edma_free_channel(unsigned channel)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(channel);
	channel = EDMA_CHAN_SLOT(channel);

	if (channel >= edma_cc[ctlr]->num_channels)
		return;

	setup_dma_interrupt(channel, RT_NULL, RT_NULL);
	/* REVISIT should probably take out of shadow region 0 */

	rt_memcpy((void *)(edmacc_regs_base[ctlr] + PARM_OFFSET(channel)),
			&dummy_paramset, PARM_SIZE);
	clear_bit(channel, edma_cc[ctlr]->edma_inuse);
}


/**
 * edma_alloc_slot - allocate DMA parameter RAM
 * @slot: specific slot to allocate; negative for "any unused slot"
 *
 * This allocates a parameter RAM slot, initializing it to hold a
 * dummy transfer.  Slots allocated using this routine have not been
 * mapped to a hardware DMA channel, and will normally be used by
 * linking to them from a slot associated with a DMA channel.
 *
 * Normal use is to pass EDMA_SLOT_ANY as the @slot, but specific
 * slots may be allocated on behalf of DSP firmware.
 *
 * Returns the number of the slot, else negative errno.
 */
int edma_alloc_slot(unsigned ctlr, int slot)
{
	if (slot >= 0)
		slot = EDMA_CHAN_SLOT(slot);

	if (slot < 0) {
		slot = edma_cc[ctlr]->num_channels;
		for (;;) {
			slot = find_next_zero_bit(edma_cc[ctlr]->edma_inuse,
					edma_cc[ctlr]->num_slots, slot);
			if (slot == edma_cc[ctlr]->num_slots)
				return -RT_ENOMEM;
			if (!test_and_set_bit(slot, edma_cc[ctlr]->edma_inuse))
				break;
		}
	} else if (slot < edma_cc[ctlr]->num_channels ||
			slot >= edma_cc[ctlr]->num_slots) {
		return -RT_ERROR;
	} else if (test_and_set_bit(slot, edma_cc[ctlr]->edma_inuse)) {
		return -RT_EBUSY;
	}

	rt_memcpy((void *)(edmacc_regs_base[ctlr] + PARM_OFFSET(slot)),
			&dummy_paramset, PARM_SIZE);

	return EDMA_CTLR_CHAN(ctlr, slot);
}


/**
 * edma_free_slot - deallocate DMA parameter RAM
 * @slot: parameter RAM slot returned from edma_alloc_slot()
 *
 * This deallocates the parameter RAM slot allocated by edma_alloc_slot().
 * Callers are responsible for ensuring the slot is inactive, and will
 * not be activated.
 */
void edma_free_slot(unsigned slot)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(slot);
	slot = EDMA_CHAN_SLOT(slot);

	if (slot < edma_cc[ctlr]->num_channels ||
		slot >= edma_cc[ctlr]->num_slots)
		return;

	rt_memcpy((void *)(edmacc_regs_base[ctlr] + PARM_OFFSET(slot)),
			&dummy_paramset, PARM_SIZE);
	clear_bit(slot, edma_cc[ctlr]->edma_inuse);
}



/**
 * edma_alloc_cont_slots- alloc contiguous parameter RAM slots
 * The API will return the starting point of a set of
 * contiguous parameter RAM slots that have been requested
 *
 * @id: can only be EDMA_CONT_PARAMS_ANY or EDMA_CONT_PARAMS_FIXED_EXACT
 * or EDMA_CONT_PARAMS_FIXED_NOT_EXACT
 * @count: number of contiguous Paramter RAM slots
 * @slot  - the start value of Parameter RAM slot that should be passed if id
 * is EDMA_CONT_PARAMS_FIXED_EXACT or EDMA_CONT_PARAMS_FIXED_NOT_EXACT
 *
 * If id is EDMA_CONT_PARAMS_ANY then the API starts looking for a set of
 * contiguous Parameter RAM slots from parameter RAM 64 in the case of
 * DaVinci SOCs and 32 in the case of DA8xx SOCs.
 *
 * If id is EDMA_CONT_PARAMS_FIXED_EXACT then the API starts looking for a
 * set of contiguous parameter RAM slots from the "slot" that is passed as an
 * argument to the API.
 *
 * If id is EDMA_CONT_PARAMS_FIXED_NOT_EXACT then the API initially tries
 * starts looking for a set of contiguous parameter RAMs from the "slot"
 * that is passed as an argument to the API. On failure the API will try to
 * find a set of contiguous Parameter RAM slots from the remaining Parameter
 * RAM slots
 */
int edma_alloc_cont_slots(unsigned ctlr, unsigned int id, int slot, int count)
{
	/*
	 * The start slot requested should be greater than
	 * the number of channels and lesser than the total number
	 * of slots
	 */
	if ((id != EDMA_CONT_PARAMS_ANY) &&
		(slot < edma_cc[ctlr]->num_channels ||
		slot >= edma_cc[ctlr]->num_slots))
		return -RT_ERROR;

	/*
	 * The number of parameter RAM slots requested cannot be less than 1
	 * and cannot be more than the number of slots minus the number of
	 * channels
	 */
	if (count < 1 || count >
		(edma_cc[ctlr]->num_slots - edma_cc[ctlr]->num_channels))
		return -RT_ERROR;

	switch (id) {
	case EDMA_CONT_PARAMS_ANY:
		return reserve_contiguous_slots(ctlr, id, count,
						 edma_cc[ctlr]->num_channels);
	case EDMA_CONT_PARAMS_FIXED_EXACT:
	case EDMA_CONT_PARAMS_FIXED_NOT_EXACT:
		return reserve_contiguous_slots(ctlr, id, count, slot);
	default:
		return -RT_ERROR;
	}

}


/**
 * edma_free_cont_slots - deallocate DMA parameter RAM slots
 * @slot: first parameter RAM of a set of parameter RAM slots to be freed
 * @count: the number of contiguous parameter RAM slots to be freed
 *
 * This deallocates the parameter RAM slots allocated by
 * edma_alloc_cont_slots.
 * Callers/applications need to keep track of sets of contiguous
 * parameter RAM slots that have been allocated using the edma_alloc_cont_slots
 * API.
 * Callers are responsible for ensuring the slots are inactive, and will
 * not be activated.
 */
int edma_free_cont_slots(unsigned slot, int count)
{
	unsigned ctlr, slot_to_free;
	int i;

	ctlr = EDMA_CTLR(slot);
	slot = EDMA_CHAN_SLOT(slot);

	if (slot < edma_cc[ctlr]->num_channels ||
		slot >= edma_cc[ctlr]->num_slots ||
		count < 1)
		return -RT_ERROR;

	for (i = slot; i < slot + count; ++i) {
		ctlr = EDMA_CTLR(i);
		slot_to_free = EDMA_CHAN_SLOT(i);

		rt_memcpy((void *)(edmacc_regs_base[ctlr] + PARM_OFFSET(slot_to_free)),
			&dummy_paramset, PARM_SIZE);
		clear_bit(slot_to_free, edma_cc[ctlr]->edma_inuse);
	}

	return 0;
}


/*-----------------------------------------------------------------------*/

/* Parameter RAM operations (i) -- read/write partial slots */

/**
 * edma_set_src - set initial DMA source address in parameter RAM slot
 * @slot: parameter RAM slot being configured
 * @src_port: physical address of source (memory, controller FIFO, etc)
 * @addressMode: INCR, except in very rare cases
 * @fifoWidth: ignored unless @addressMode is FIFO, else specifies the
 *	width to use when addressing the fifo (e.g. W8BIT, W32BIT)
 *
 * Note that the source address is modified during the DMA transfer
 * according to edma_set_src_index().
 */
void edma_set_src(unsigned slot, rt_uint32_t src_port,
				enum address_mode mode, enum fifo_width width)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(slot);
	slot = EDMA_CHAN_SLOT(slot);

	if (slot < edma_cc[ctlr]->num_slots) {
		unsigned int i = edma_parm_read(ctlr, PARM_OPT, slot);

		if (mode) {
			/* set SAM and program FWID */
			i = (i & ~(EDMA_FWID)) | (SAM | ((width & 0x7) << 8));
		} else {
			/* clear SAM */
			i &= ~SAM;
		}
		edma_parm_write(ctlr, PARM_OPT, slot, i);

		/* set the source port address
		   in source register of param structure */
		edma_parm_write(ctlr, PARM_SRC, slot, src_port);
	}
}


/**
 * edma_set_dest - set initial DMA destination address in parameter RAM slot
 * @slot: parameter RAM slot being configured
 * @dest_port: physical address of destination (memory, controller FIFO, etc)
 * @addressMode: INCR, except in very rare cases
 * @fifoWidth: ignored unless @addressMode is FIFO, else specifies the
 *	width to use when addressing the fifo (e.g. W8BIT, W32BIT)
 *
 * Note that the destination address is modified during the DMA transfer
 * according to edma_set_dest_index().
 */
void edma_set_dest(unsigned slot, rt_uint32_t dest_port,
				 enum address_mode mode, enum fifo_width width)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(slot);
	slot = EDMA_CHAN_SLOT(slot);

	if (slot < edma_cc[ctlr]->num_slots) {
		unsigned int i = edma_parm_read(ctlr, PARM_OPT, slot);

		if (mode) {
			/* set DAM and program FWID */
			i = (i & ~(EDMA_FWID)) | (DAM | ((width & 0x7) << 8));
		} else {
			/* clear DAM */
			i &= ~DAM;
		}
		edma_parm_write(ctlr, PARM_OPT, slot, i);
		/* set the destination port address
		   in dest register of param structure */
		edma_parm_write(ctlr, PARM_DST, slot, dest_port);
	}
}


/**
 * edma_get_position - returns the current transfer points
 * @slot: parameter RAM slot being examined
 * @src: pointer to source port position
 * @dst: pointer to destination port position
 *
 * Returns current source and destination addresses for a particular
 * parameter RAM slot.  Its channel should not be active when this is called.
 */
void edma_get_position(unsigned slot, rt_uint32_t *src, rt_uint32_t *dst)
{
	struct edmacc_param temp;
	unsigned ctlr;

	ctlr = EDMA_CTLR(slot);
	slot = EDMA_CHAN_SLOT(slot);

	edma_read_slot(EDMA_CTLR_CHAN(ctlr, slot), &temp);
	if (src != RT_NULL)
		*src = temp.src;
	if (dst != RT_NULL)
		*dst = temp.dst;
}


/**
 * edma_set_src_index - configure DMA source address indexing
 * @slot: parameter RAM slot being configured
 * @src_bidx: byte offset between source arrays in a frame
 * @src_cidx: byte offset between source frames in a block
 *
 * Offsets are specified to support either contiguous or discontiguous
 * memory transfers, or repeated access to a hardware register, as needed.
 * When accessing hardware registers, both offsets are normally zero.
 */
void edma_set_src_index(unsigned slot, rt_int16_t src_bidx, rt_int16_t src_cidx)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(slot);
	slot = EDMA_CHAN_SLOT(slot);

	if (slot < edma_cc[ctlr]->num_slots) {
		edma_parm_modify(ctlr, PARM_SRC_DST_BIDX, slot,
				0xffff0000, src_bidx);
		edma_parm_modify(ctlr, PARM_SRC_DST_CIDX, slot,
				0xffff0000, src_cidx);
	}
}


/**
 * edma_set_dest_index - configure DMA destination address indexing
 * @slot: parameter RAM slot being configured
 * @dest_bidx: byte offset between destination arrays in a frame
 * @dest_cidx: byte offset between destination frames in a block
 *
 * Offsets are specified to support either contiguous or discontiguous
 * memory transfers, or repeated access to a hardware register, as needed.
 * When accessing hardware registers, both offsets are normally zero.
 */
void edma_set_dest_index(unsigned slot, rt_int16_t dest_bidx, rt_int16_t dest_cidx)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(slot);
	slot = EDMA_CHAN_SLOT(slot);

	if (slot < edma_cc[ctlr]->num_slots) {
		edma_parm_modify(ctlr, PARM_SRC_DST_BIDX, slot,
				0x0000ffff, dest_bidx << 16);
		edma_parm_modify(ctlr, PARM_SRC_DST_CIDX, slot,
				0x0000ffff, dest_cidx << 16);
	}
}


/**
 * edma_set_transfer_params - configure DMA transfer parameters
 * @slot: parameter RAM slot being configured
 * @acnt: how many bytes per array (at least one)
 * @bcnt: how many arrays per frame (at least one)
 * @ccnt: how many frames per block (at least one)
 * @bcnt_rld: used only for A-Synchronized transfers; this specifies
 *	the value to reload into bcnt when it decrements to zero
 * @sync_mode: ASYNC or ABSYNC
 *
 * See the EDMA3 documentation to understand how to configure and link
 * transfers using the fields in PaRAM slots.  If you are not doing it
 * all at once with edma_write_slot(), you will use this routine
 * plus two calls each for source and destination, setting the initial
 * address and saying how to index that address.
 *
 * An example of an A-Synchronized transfer is a serial link using a
 * single word shift register.  In that case, @acnt would be equal to
 * that word size; the serial controller issues a DMA synchronization
 * event to transfer each word, and memory access by the DMA transfer
 * controller will be word-at-a-time.
 *
 * An example of an AB-Synchronized transfer is a device using a FIFO.
 * In that case, @acnt equals the FIFO width and @bcnt equals its depth.
 * The controller with the FIFO issues DMA synchronization events when
 * the FIFO threshold is reached, and the DMA transfer controller will
 * transfer one frame to (or from) the FIFO.  It will probably use
 * efficient burst modes to access memory.
 */
void edma_set_transfer_params(unsigned slot,
		rt_uint16_t acnt, rt_uint16_t bcnt, rt_uint16_t ccnt,
		rt_uint16_t bcnt_rld, enum sync_dimension sync_mode)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(slot);
	slot = EDMA_CHAN_SLOT(slot);

	if (slot < edma_cc[ctlr]->num_slots) {
		edma_parm_modify(ctlr, PARM_LINK_BCNTRLD, slot,
				0x0000ffff, bcnt_rld << 16);
		if (sync_mode == ASYNC)
			edma_parm_and(ctlr, PARM_OPT, slot, ~SYNCDIM);
		else
			edma_parm_or(ctlr, PARM_OPT, slot, SYNCDIM);
		/* Set the acount, bcount, ccount registers */
		edma_parm_write(ctlr, PARM_A_B_CNT, slot, (bcnt << 16) | acnt);
		edma_parm_write(ctlr, PARM_CCNT, slot, ccnt);
	}
}


/**
 * edma_link - link one parameter RAM slot to another
 * @from: parameter RAM slot originating the link
 * @to: parameter RAM slot which is the link target
 *
 * The originating slot should not be part of any active DMA transfer.
 */
void edma_link(unsigned from, unsigned to)
{
	unsigned ctlr_from, ctlr_to;

	ctlr_from = EDMA_CTLR(from);
	from = EDMA_CHAN_SLOT(from);
	ctlr_to = EDMA_CTLR(to);
	to = EDMA_CHAN_SLOT(to);

	if (from >= edma_cc[ctlr_from]->num_slots)
		return;
	if (to >= edma_cc[ctlr_to]->num_slots)
		return;
	edma_parm_modify(ctlr_from, PARM_LINK_BCNTRLD, from, 0xffff0000,
				PARM_OFFSET(to));
}


/**
 * edma_unlink - cut link from one parameter RAM slot
 * @from: parameter RAM slot originating the link
 *
 * The originating slot should not be part of any active DMA transfer.
 * Its link is set to 0xffff.
 */
void edma_unlink(unsigned from)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(from);
	from = EDMA_CHAN_SLOT(from);

	if (from >= edma_cc[ctlr]->num_slots)
		return;
	edma_parm_or(ctlr, PARM_LINK_BCNTRLD, from, 0xffff);
}


/*-----------------------------------------------------------------------*/

/* Parameter RAM operations (ii) -- read/write whole parameter sets */

/**
 * edma_write_slot - write parameter RAM data for slot
 * @slot: number of parameter RAM slot being modified
 * @param: data to be written into parameter RAM slot
 *
 * Use this to assign all parameters of a transfer at once.  This
 * allows more efficient setup of transfers than issuing multiple
 * calls to set up those parameters in small pieces, and provides
 * complete control over all transfer options.
 */
void edma_write_slot(unsigned slot, const struct edmacc_param *param)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(slot);
	slot = EDMA_CHAN_SLOT(slot);

	if (slot >= edma_cc[ctlr]->num_slots)
		return;
	rt_memcpy((void *)(edmacc_regs_base[ctlr] + PARM_OFFSET(slot)), param,
			PARM_SIZE);
}


/**
 * edma_read_slot - read parameter RAM data from slot
 * @slot: number of parameter RAM slot being copied
 * @param: where to store copy of parameter RAM data
 *
 * Use this to read data from a parameter RAM slot, perhaps to
 * save them as a template for later reuse.
 */
void edma_read_slot(unsigned slot, struct edmacc_param *param)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(slot);
	slot = EDMA_CHAN_SLOT(slot);

	if (slot >= edma_cc[ctlr]->num_slots)
		return;
	rt_memcpy(param, (void *)(edmacc_regs_base[ctlr] + PARM_OFFSET(slot)),
			PARM_SIZE);
}


/*-----------------------------------------------------------------------*/

/* Various EDMA channel control operations */

/**
 * edma_pause - pause dma on a channel
 * @channel: on which edma_start() has been called
 *
 * This temporarily disables EDMA hardware events on the specified channel,
 * preventing them from triggering new transfers on its behalf
 */
void edma_pause(unsigned channel)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(channel);
	channel = EDMA_CHAN_SLOT(channel);

	if (channel < edma_cc[ctlr]->num_channels) {
		unsigned int mask = BIT(channel & 0x1f);

		edma_shadow0_write_array(ctlr, SH_EECR, channel >> 5, mask);
	}
}


/**
 * edma_resume - resumes dma on a paused channel
 * @channel: on which edma_pause() has been called
 *
 * This re-enables EDMA hardware events on the specified channel.
 */
void edma_resume(unsigned channel)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(channel);
	channel = EDMA_CHAN_SLOT(channel);

	if (channel < edma_cc[ctlr]->num_channels) {
		unsigned int mask = BIT(channel & 0x1f);

		edma_shadow0_write_array(ctlr, SH_EESR, channel >> 5, mask);
	}
}


/**
 * edma_start - start dma on a channel
 * @channel: channel being activated
 *
 * Channels with event associations will be triggered by their hardware
 * events, and channels without such associations will be triggered by
 * software.  (At this writing there is no interface for using software
 * triggers except with channels that don't support hardware triggers.)
 *
 * Returns zero on success, else negative errno.
 */
int edma_start(unsigned channel)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(channel);
	channel = EDMA_CHAN_SLOT(channel);

	if (channel < edma_cc[ctlr]->num_channels) {
		int j = channel >> 5;
		unsigned int mask = BIT(channel & 0x1f);

		/* EDMA channels without event association */
		if (test_bit(channel, edma_cc[ctlr]->edma_unused)) {
			edma_dbg("EDMA: ESR%d %08x\n", j,
				edma_shadow0_read_array(ctlr, SH_ESR, j));
			edma_shadow0_write_array(ctlr, SH_ESR, j, mask);
			return 0;
		}

		/* EDMA channel with event association */
		edma_dbg("EDMA: ER%d %08x\n", j,
			edma_shadow0_read_array(ctlr, SH_ER, j));
		/* Clear any pending event or error */
		edma_write_array(ctlr, EDMA_ECR, j, mask);
		edma_write_array(ctlr, EDMA_EMCR, j, mask);
		/* Clear any SER */
		edma_shadow0_write_array(ctlr, SH_SECR, j, mask);
		edma_shadow0_write_array(ctlr, SH_EESR, j, mask);
		edma_dbg("EDMA: EER%d %08x\n", j,
			edma_shadow0_read_array(ctlr, SH_EER, j));
		return 0;
	}

	return -RT_ERROR;
}


/**
 * edma_stop - stops dma on the channel passed
 * @channel: channel being deactivated
 *
 * When @lch is a channel, any active transfer is paused and
 * all pending hardware events are cleared.  The current transfer
 * may not be resumed, and the channel's Parameter RAM should be
 * reinitialized before being reused.
 */
void edma_stop(unsigned channel)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(channel);
	channel = EDMA_CHAN_SLOT(channel);

	if (channel < edma_cc[ctlr]->num_channels) {
		int j = channel >> 5;
		unsigned int mask = BIT(channel & 0x1f);

		edma_shadow0_write_array(ctlr, SH_EECR, j, mask);
		edma_shadow0_write_array(ctlr, SH_ECR, j, mask);
		edma_shadow0_write_array(ctlr, SH_SECR, j, mask);
		edma_write_array(ctlr, EDMA_EMCR, j, mask);

		edma_dbg("EDMA: EER%d %08x\n", j,
				edma_shadow0_read_array(ctlr, SH_EER, j));

		/* REVISIT:  consider guarding against inappropriate event
		 * chaining by overwriting with dummy_paramset.
		 */
	}
}


/******************************************************************************
 *
 * It cleans ParamEntry qand bring back EDMA to initial state if media has
 * been removed before EDMA has finished.It is usedful for removable media.
 * Arguments:
 *      ch_no     - channel no
 *
 * Return: zero on success, or corresponding error no on failure
 *
 * FIXME this should not be needed ... edma_stop() should suffice.
 *
 *****************************************************************************/

void edma_clean_channel(unsigned channel)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(channel);
	channel = EDMA_CHAN_SLOT(channel);

	if (channel < edma_cc[ctlr]->num_channels) {
		int j = (channel >> 5);
		unsigned int mask = BIT(channel & 0x1f);

		edma_dbg("EDMA: EMR%d %08x\n", j,
				edma_read_array(ctlr, EDMA_EMR, j));
		edma_shadow0_write_array(ctlr, SH_ECR, j, mask);
		/* Clear the corresponding EMR bits */
		edma_write_array(ctlr, EDMA_EMCR, j, mask);
		/* Clear any SER */
		edma_shadow0_write_array(ctlr, SH_SECR, j, mask);
		edma_write(ctlr, EDMA_CCERRCLR, BIT(16) | BIT(1) | BIT(0));
	}
}


/*
 * edma_clear_event - clear an outstanding event on the DMA channel
 * Arguments:
 *	channel - channel number
 */
void edma_clear_event(unsigned channel)
{
	unsigned ctlr;

	ctlr = EDMA_CTLR(channel);
	channel = EDMA_CHAN_SLOT(channel);

	if (channel >= edma_cc[ctlr]->num_channels)
		return;
	if (channel < 32)
		edma_write(ctlr, EDMA_ECR, BIT(channel));
	else
		edma_write(ctlr, EDMA_ECRH, BIT(channel - 32));
}


/*-----------------------------------------------------------------------*/

int edma_init(struct edma_soc_info **info)
{
	//struct edma_soc_info	**info = pdev->dev.platform_data;
	const rt_int8_t		(*queue_priority_mapping)[2];
	const rt_int8_t		(*queue_tc_mapping)[2];
	int			i, j, off, ln, found = 0;
	int			status = -1;
	const rt_int16_t		(*rsv_chans)[2];
	const rt_int16_t		(*rsv_slots)[2];
	int			irq[EDMA_MAX_CC] = {0, 0};
	int			err_irq[EDMA_MAX_CC] = {0, 0};

	RT_ASSERT(info != RT_NULL);

	psc_change_state(DAVINCI_DM365_LPSC_TPCC, PSC_ENABLE);
	psc_change_state(DAVINCI_DM365_LPSC_TPTC0, PSC_ENABLE);
	psc_change_state(DAVINCI_DM365_LPSC_TPTC1, PSC_ENABLE);
	psc_change_state(DAVINCI_DM365_LPSC_TPTC2, PSC_ENABLE);
	psc_change_state(DAVINCI_DM365_LPSC_TPTC3, PSC_ENABLE);

	edmacc_regs_base[0] = (void *)EDMA_CC0_BASE_REG;

	edma_cc[0] = rt_malloc(sizeof(struct edma));
	if (!edma_cc[0]) {
		status = -RT_ENOMEM;
		goto fail1;
	}
	rt_memset(edma_cc[0], 0, sizeof(struct edma));

	edma_cc[0]->num_channels = min_t(unsigned, info[0]->n_channel,
						EDMA_MAX_DMACH);
	edma_cc[0]->num_slots = min_t(unsigned, info[0]->n_slot,
						EDMA_MAX_PARAMENTRY);
	edma_cc[0]->num_cc = min_t(unsigned, info[0]->n_cc,
						EDMA_MAX_CC);

	edma_cc[0]->default_queue = info[0]->default_queue;
	if (!edma_cc[0]->default_queue)
		edma_cc[0]->default_queue = EVENTQ_1;

	edma_dbg("DMA REG BASE ADDR=%p\n",
		edmacc_regs_base[j]);

	for (i = 0; i < edma_cc[0]->num_slots; i++)
		rt_memcpy((void *)(edmacc_regs_base[0] + PARM_OFFSET(i)),
				&dummy_paramset, PARM_SIZE);

	/* Mark all channels as unused */
	rt_memset(edma_cc[0]->edma_unused, 0xff,
		sizeof(edma_cc[0]->edma_unused));

	edma_cc[0]->irq_res_start = IRQ_CCINT0;
	rt_hw_interrupt_install(IRQ_CCINT0, dma_irq_handler, RT_NULL, "edma");
	rt_hw_interrupt_umask(IRQ_CCINT0);

	edma_cc[0]->irq_res_end = IRQ_CCERRINT;
	rt_hw_interrupt_install(IRQ_CCERRINT, dma_ccerr_handler, RT_NULL, "edma_error");
	rt_hw_interrupt_umask(IRQ_CCERRINT);

	/* Everything lives on transfer controller 1 until otherwise
	 * specified. This way, long transfers on the low priority queue
	 * started by the codec engine will not cause audio defects.
	 */
	for (i = 0; i < edma_cc[0]->num_channels; i++)
		map_dmach_queue(0, i, EVENTQ_1);

	queue_tc_mapping = info[0]->queue_tc_mapping;
	queue_priority_mapping = info[0]->queue_priority_mapping;

	/* Event queue to TC mapping */
	for (i = 0; queue_tc_mapping[i][0] != -1; i++)
		map_queue_tc(0, queue_tc_mapping[i][0],
				queue_tc_mapping[i][1]);

	/* Event queue priority mapping */
	for (i = 0; queue_priority_mapping[i][0] != -1; i++)
		assign_priority_to_queue(0,
					queue_priority_mapping[i][0],
					queue_priority_mapping[i][1]);

	/* Map the channel to param entry if channel mapping logic
	 * exist
	 */
	if (edma_read(0, EDMA_CCCFG) & CHMAP_EXIST)
		map_dmach_param(0);

	for (i = 0; i < info[0]->n_region; i++) {
		edma_write_array2(0, EDMA_DRAE, i, 0, 0x0);
		edma_write_array2(0, EDMA_DRAE, i, 1, 0x0);
		edma_write_array(0, EDMA_QRAE, i, 0x0);
	}
	arch_num_cc++;

	if (tc_errs_handled) {
 		rt_hw_interrupt_install(IRQ_TCERRINT0, dma_tc0err_handler, "edma_tc0");
		rt_hw_interrupt_umask(IRQ_TCERRINT0);
		rt_hw_interrupt_install(IRQ_TCERRINT, dma_tc1err_handler, "edma_tc1");
		rt_hw_interrupt_umask(IRQ_TCERRINT);
	}

	return 0;

fail:

fail1:
	rt_free(edma_cc[0]);

	return status;
}