symbian-qemu-0.9.1-12/qemu-symbian-svp/hw/etraxfs_dma.c
author johnathan.white@2718R8BGH51.accenture.com
Mon, 08 Mar 2010 18:45:03 +0000
changeset 46 b6935a90ca64
parent 1 2fb8b9db1c86
permissions -rw-r--r--
Modify framebuffer and NGA framebuffer to read screen size from board model dtb file. Optimise memory usuage of frame buffer Add example minigui application with hooks to profiler (which writes results to S:\). Modified NGA framebuffer to run its own dfc queue at high priority

/*
 * QEMU ETRAX DMA Controller.
 *
 * Copyright (c) 2008 Edgar E. Iglesias, Axis Communications AB.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include <stdio.h>
#include <sys/time.h>
#include "hw.h"
#include "qemu-common.h"
#include "sysemu.h"

#include "etraxfs_dma.h"

#define D(x)

#define RW_DATA           0x0
#define RW_SAVED_DATA     0x58
#define RW_SAVED_DATA_BUF 0x5c
#define RW_GROUP          0x60
#define RW_GROUP_DOWN     0x7c
#define RW_CMD            0x80
#define RW_CFG            0x84
#define RW_STAT           0x88
#define RW_INTR_MASK      0x8c
#define RW_ACK_INTR       0x90
#define R_INTR            0x94
#define R_MASKED_INTR     0x98
#define RW_STREAM_CMD     0x9c

#define DMA_REG_MAX   0x100

/* descriptors */

// ------------------------------------------------------------ dma_descr_group
typedef struct dma_descr_group {
  struct dma_descr_group       *next;
  unsigned                      eol        : 1;
  unsigned                      tol        : 1;
  unsigned                      bol        : 1;
  unsigned                                 : 1;
  unsigned                      intr       : 1;
  unsigned                                 : 2;
  unsigned                      en         : 1;
  unsigned                                 : 7;
  unsigned                      dis        : 1;
  unsigned                      md         : 16;
  struct dma_descr_group       *up;
  union {
    struct dma_descr_context   *context;
    struct dma_descr_group     *group;
  }                             down;
} dma_descr_group;

// ---------------------------------------------------------- dma_descr_context
typedef struct dma_descr_context {
  struct dma_descr_context     *next;
  unsigned                      eol        : 1;
  unsigned                                 : 3;
  unsigned                      intr       : 1;
  unsigned                                 : 1;
  unsigned                      store_mode : 1;
  unsigned                      en         : 1;
  unsigned                                 : 7;
  unsigned                      dis        : 1;
  unsigned                      md0        : 16;
  unsigned                      md1;
  unsigned                      md2;
  unsigned                      md3;
  unsigned                      md4;
  struct dma_descr_data        *saved_data;
  char                         *saved_data_buf;
} dma_descr_context;

// ------------------------------------------------------------- dma_descr_data
typedef struct dma_descr_data {
  struct dma_descr_data        *next;
  char                         *buf;
  unsigned                      eol        : 1;
  unsigned                                 : 2;
  unsigned                      out_eop    : 1;
  unsigned                      intr       : 1;
  unsigned                      wait       : 1;
  unsigned                                 : 2;
  unsigned                                 : 3;
  unsigned                      in_eop     : 1;
  unsigned                                 : 4;
  unsigned                      md         : 16;
  char                         *after;
} dma_descr_data;

/* Constants */
enum {
  regk_dma_ack_pkt                         = 0x00000100,
  regk_dma_anytime                         = 0x00000001,
  regk_dma_array                           = 0x00000008,
  regk_dma_burst                           = 0x00000020,
  regk_dma_client                          = 0x00000002,
  regk_dma_copy_next                       = 0x00000010,
  regk_dma_copy_up                         = 0x00000020,
  regk_dma_data_at_eol                     = 0x00000001,
  regk_dma_dis_c                           = 0x00000010,
  regk_dma_dis_g                           = 0x00000020,
  regk_dma_idle                            = 0x00000001,
  regk_dma_intern                          = 0x00000004,
  regk_dma_load_c                          = 0x00000200,
  regk_dma_load_c_n                        = 0x00000280,
  regk_dma_load_c_next                     = 0x00000240,
  regk_dma_load_d                          = 0x00000140,
  regk_dma_load_g                          = 0x00000300,
  regk_dma_load_g_down                     = 0x000003c0,
  regk_dma_load_g_next                     = 0x00000340,
  regk_dma_load_g_up                       = 0x00000380,
  regk_dma_next_en                         = 0x00000010,
  regk_dma_next_pkt                        = 0x00000010,
  regk_dma_no                              = 0x00000000,
  regk_dma_only_at_wait                    = 0x00000000,
  regk_dma_restore                         = 0x00000020,
  regk_dma_rst                             = 0x00000001,
  regk_dma_running                         = 0x00000004,
  regk_dma_rw_cfg_default                  = 0x00000000,
  regk_dma_rw_cmd_default                  = 0x00000000,
  regk_dma_rw_intr_mask_default            = 0x00000000,
  regk_dma_rw_stat_default                 = 0x00000101,
  regk_dma_rw_stream_cmd_default           = 0x00000000,
  regk_dma_save_down                       = 0x00000020,
  regk_dma_save_up                         = 0x00000020,
  regk_dma_set_reg                         = 0x00000050,
  regk_dma_set_w_size1                     = 0x00000190,
  regk_dma_set_w_size2                     = 0x000001a0,
  regk_dma_set_w_size4                     = 0x000001c0,
  regk_dma_stopped                         = 0x00000002,
  regk_dma_store_c                         = 0x00000002,
  regk_dma_store_descr                     = 0x00000000,
  regk_dma_store_g                         = 0x00000004,
  regk_dma_store_md                        = 0x00000001,
  regk_dma_sw                              = 0x00000008,
  regk_dma_update_down                     = 0x00000020,
  regk_dma_yes                             = 0x00000001
};

enum dma_ch_state
{
	RST = 1,
	STOPPED = 2,
	RUNNING = 4
};

struct fs_dma_channel
{
	qemu_irq *irq;
	struct etraxfs_dma_client *client;

	/* Internal status.  */
	int stream_cmd_src;
	enum dma_ch_state state;

	unsigned int input : 1;
	unsigned int eol : 1;

	struct dma_descr_group current_g;
	struct dma_descr_context current_c;
	struct dma_descr_data current_d;

	/* Controll registers.  */
	uint32_t regs[DMA_REG_MAX];
};

struct fs_dma_ctrl
{
	int map;
	CPUState *env;

	int nr_channels;
	struct fs_dma_channel *channels;

        QEMUBH *bh;
};

static inline uint32_t channel_reg(struct fs_dma_ctrl *ctrl, int c, int reg)
{
	return ctrl->channels[c].regs[reg];
}

static inline int channel_stopped(struct fs_dma_ctrl *ctrl, int c)
{
	return channel_reg(ctrl, c, RW_CFG) & 2;
}

static inline int channel_en(struct fs_dma_ctrl *ctrl, int c)
{
	return (channel_reg(ctrl, c, RW_CFG) & 1)
		&& ctrl->channels[c].client;
}

static inline int fs_channel(target_phys_addr_t addr)
{
	/* Every channel has a 0x2000 ctrl register map.  */
	return addr >> 13;
}

#ifdef USE_THIS_DEAD_CODE
static void channel_load_g(struct fs_dma_ctrl *ctrl, int c)
{
	target_phys_addr_t addr = channel_reg(ctrl, c, RW_GROUP);

	/* Load and decode. FIXME: handle endianness.  */
	cpu_physical_memory_read (addr, 
				  (void *) &ctrl->channels[c].current_g, 
				  sizeof ctrl->channels[c].current_g);
}

static void dump_c(int ch, struct dma_descr_context *c)
{
	printf("%s ch=%d\n", __func__, ch);
	printf("next=%p\n", c->next);
	printf("saved_data=%p\n", c->saved_data);
	printf("saved_data_buf=%p\n", c->saved_data_buf);
	printf("eol=%x\n", (uint32_t) c->eol);
}

static void dump_d(int ch, struct dma_descr_data *d)
{
	printf("%s ch=%d\n", __func__, ch);
	printf("next=%p\n", d->next);
	printf("buf=%p\n", d->buf);
	printf("after=%p\n", d->after);
	printf("intr=%x\n", (uint32_t) d->intr);
	printf("out_eop=%x\n", (uint32_t) d->out_eop);
	printf("in_eop=%x\n", (uint32_t) d->in_eop);
	printf("eol=%x\n", (uint32_t) d->eol);
}
#endif

static void channel_load_c(struct fs_dma_ctrl *ctrl, int c)
{
	target_phys_addr_t addr = channel_reg(ctrl, c, RW_GROUP_DOWN);

	/* Load and decode. FIXME: handle endianness.  */
	cpu_physical_memory_read (addr, 
				  (void *) &ctrl->channels[c].current_c, 
				  sizeof ctrl->channels[c].current_c);

	D(dump_c(c, &ctrl->channels[c].current_c));
	/* I guess this should update the current pos.  */
	ctrl->channels[c].regs[RW_SAVED_DATA] =
		(uint32_t)(unsigned long)ctrl->channels[c].current_c.saved_data;
	ctrl->channels[c].regs[RW_SAVED_DATA_BUF] =
		(uint32_t)(unsigned long)ctrl->channels[c].current_c.saved_data_buf;
}

static void channel_load_d(struct fs_dma_ctrl *ctrl, int c)
{
	target_phys_addr_t addr = channel_reg(ctrl, c, RW_SAVED_DATA);

	/* Load and decode. FIXME: handle endianness.  */
	D(printf("%s ch=%d addr=%x\n", __func__, c, addr));
	cpu_physical_memory_read (addr,
				  (void *) &ctrl->channels[c].current_d, 
				  sizeof ctrl->channels[c].current_d);

	D(dump_d(c, &ctrl->channels[c].current_d));
	ctrl->channels[c].regs[RW_DATA] = addr;
}

static void channel_store_c(struct fs_dma_ctrl *ctrl, int c)
{
	target_phys_addr_t addr = channel_reg(ctrl, c, RW_GROUP_DOWN);

	/* Encode and store. FIXME: handle endianness.  */
	D(printf("%s ch=%d addr=%x\n", __func__, c, addr));
	D(dump_d(c, &ctrl->channels[c].current_d));
	cpu_physical_memory_write (addr,
				  (void *) &ctrl->channels[c].current_c,
				  sizeof ctrl->channels[c].current_c);
}

static void channel_store_d(struct fs_dma_ctrl *ctrl, int c)
{
	target_phys_addr_t addr = channel_reg(ctrl, c, RW_SAVED_DATA);

	/* Encode and store. FIXME: handle endianness.  */
	D(printf("%s ch=%d addr=%x\n", __func__, c, addr));
	cpu_physical_memory_write (addr,
				  (void *) &ctrl->channels[c].current_d, 
				  sizeof ctrl->channels[c].current_d);
}

static inline void channel_stop(struct fs_dma_ctrl *ctrl, int c)
{
	/* FIXME:  */
}

static inline void channel_start(struct fs_dma_ctrl *ctrl, int c)
{
	if (ctrl->channels[c].client)
	{
		ctrl->channels[c].eol = 0;
		ctrl->channels[c].state = RUNNING;
	} else
		printf("WARNING: starting DMA ch %d with no client\n", c);

        qemu_bh_schedule_idle(ctrl->bh);
}

static void channel_continue(struct fs_dma_ctrl *ctrl, int c)
{
	if (!channel_en(ctrl, c) 
	    || channel_stopped(ctrl, c)
	    || ctrl->channels[c].state != RUNNING
	    /* Only reload the current data descriptor if it has eol set.  */
	    || !ctrl->channels[c].current_d.eol) {
		D(printf("continue failed ch=%d state=%d stopped=%d en=%d eol=%d\n", 
			 c, ctrl->channels[c].state,
			 channel_stopped(ctrl, c),
			 channel_en(ctrl,c),
			 ctrl->channels[c].eol));
		D(dump_d(c, &ctrl->channels[c].current_d));
		return;
	}

	/* Reload the current descriptor.  */
	channel_load_d(ctrl, c);

	/* If the current descriptor cleared the eol flag and we had already
	   reached eol state, do the continue.  */
	if (!ctrl->channels[c].current_d.eol && ctrl->channels[c].eol) {
		D(printf("continue %d ok %p\n", c,
			 ctrl->channels[c].current_d.next));
		ctrl->channels[c].regs[RW_SAVED_DATA] =
			(uint32_t)(unsigned long)ctrl->channels[c].current_d.next;
		channel_load_d(ctrl, c);
		channel_start(ctrl, c);
	}
	ctrl->channels[c].regs[RW_SAVED_DATA_BUF] =
		(uint32_t)(unsigned long)ctrl->channels[c].current_d.buf;
}

static void channel_stream_cmd(struct fs_dma_ctrl *ctrl, int c, uint32_t v)
{
	unsigned int cmd = v & ((1 << 10) - 1);

	D(printf("%s ch=%d cmd=%x\n",
		 __func__, c, cmd));
	if (cmd & regk_dma_load_d) {
		channel_load_d(ctrl, c);
		if (cmd & regk_dma_burst)
			channel_start(ctrl, c);
	}

	if (cmd & regk_dma_load_c) {
		channel_load_c(ctrl, c);
		channel_start(ctrl, c);
	}
}

static void channel_update_irq(struct fs_dma_ctrl *ctrl, int c)
{
	D(printf("%s %d\n", __func__, c));
        ctrl->channels[c].regs[R_INTR] &=
		~(ctrl->channels[c].regs[RW_ACK_INTR]);

        ctrl->channels[c].regs[R_MASKED_INTR] =
		ctrl->channels[c].regs[R_INTR]
		& ctrl->channels[c].regs[RW_INTR_MASK];

	D(printf("%s: chan=%d masked_intr=%x\n", __func__, 
		 c,
		 ctrl->channels[c].regs[R_MASKED_INTR]));

        if (ctrl->channels[c].regs[R_MASKED_INTR])
                qemu_irq_raise(ctrl->channels[c].irq[0]);
        else
                qemu_irq_lower(ctrl->channels[c].irq[0]);
}

static int channel_out_run(struct fs_dma_ctrl *ctrl, int c)
{
	uint32_t len;
	uint32_t saved_data_buf;
	unsigned char buf[2 * 1024];

	if (ctrl->channels[c].eol)
		return 0;

	do {
		saved_data_buf = channel_reg(ctrl, c, RW_SAVED_DATA_BUF);

		D(printf("ch=%d buf=%x after=%x saved_data_buf=%x\n",
			 c,
			 (uint32_t)ctrl->channels[c].current_d.buf,
			 (uint32_t)ctrl->channels[c].current_d.after,
			 saved_data_buf));

		len = (uint32_t)(unsigned long)
			ctrl->channels[c].current_d.after;
		len -= saved_data_buf;

		if (len > sizeof buf)
			len = sizeof buf;
		cpu_physical_memory_read (saved_data_buf, buf, len);

		D(printf("channel %d pushes %x %u bytes\n", c, 
			 saved_data_buf, len));

		if (ctrl->channels[c].client->client.push)
			ctrl->channels[c].client->client.push(
				ctrl->channels[c].client->client.opaque,
				buf, len);
		else
			printf("WARNING: DMA ch%d dataloss,"
			       " no attached client.\n", c);

		saved_data_buf += len;

		if (saved_data_buf == (uint32_t)(unsigned long)
				ctrl->channels[c].current_d.after) {
			/* Done. Step to next.  */
			if (ctrl->channels[c].current_d.out_eop) {
				/* TODO: signal eop to the client.  */
				D(printf("signal eop\n"));
			}
			if (ctrl->channels[c].current_d.intr) {
				/* TODO: signal eop to the client.  */
				/* data intr.  */
				D(printf("signal intr\n"));
				ctrl->channels[c].regs[R_INTR] |= (1 << 2);
				channel_update_irq(ctrl, c);
			}
			if (ctrl->channels[c].current_d.eol) {
				D(printf("channel %d EOL\n", c));
				ctrl->channels[c].eol = 1;

				/* Mark the context as disabled.  */
				ctrl->channels[c].current_c.dis = 1;
				channel_store_c(ctrl, c);

				channel_stop(ctrl, c);
			} else {
				ctrl->channels[c].regs[RW_SAVED_DATA] =
					(uint32_t)(unsigned long)ctrl->
						channels[c].current_d.next;
				/* Load new descriptor.  */
				channel_load_d(ctrl, c);
				saved_data_buf = (uint32_t)(unsigned long)
					ctrl->channels[c].current_d.buf;
			}

			channel_store_d(ctrl, c);
			ctrl->channels[c].regs[RW_SAVED_DATA_BUF] =
							saved_data_buf;
			D(dump_d(c, &ctrl->channels[c].current_d));
		}
		ctrl->channels[c].regs[RW_SAVED_DATA_BUF] = saved_data_buf;
	} while (!ctrl->channels[c].eol);
	return 1;
}

static int channel_in_process(struct fs_dma_ctrl *ctrl, int c, 
			      unsigned char *buf, int buflen, int eop)
{
	uint32_t len;
	uint32_t saved_data_buf;

	if (ctrl->channels[c].eol == 1)
		return 0;

	saved_data_buf = channel_reg(ctrl, c, RW_SAVED_DATA_BUF);
	len = (uint32_t)(unsigned long)ctrl->channels[c].current_d.after;
	len -= saved_data_buf;
	
	if (len > buflen)
		len = buflen;

	cpu_physical_memory_write (saved_data_buf, buf, len);
	saved_data_buf += len;

	if (saved_data_buf ==
	    (uint32_t)(unsigned long)ctrl->channels[c].current_d.after
	    || eop) {
		uint32_t r_intr = ctrl->channels[c].regs[R_INTR];

		D(printf("in dscr end len=%d\n", 
			 ctrl->channels[c].current_d.after
			 - ctrl->channels[c].current_d.buf));
		ctrl->channels[c].current_d.after = 
			(void *)(unsigned long) saved_data_buf;

		/* Done. Step to next.  */
		if (ctrl->channels[c].current_d.intr) {
			/* TODO: signal eop to the client.  */
			/* data intr.  */
			ctrl->channels[c].regs[R_INTR] |= 3;
		}
		if (eop) {
			ctrl->channels[c].current_d.in_eop = 1;
			ctrl->channels[c].regs[R_INTR] |= 8;
		}
		if (r_intr != ctrl->channels[c].regs[R_INTR])
			channel_update_irq(ctrl, c);

		channel_store_d(ctrl, c);
		D(dump_d(c, &ctrl->channels[c].current_d));

		if (ctrl->channels[c].current_d.eol) {
			D(printf("channel %d EOL\n", c));
			ctrl->channels[c].eol = 1;

			/* Mark the context as disabled.  */
			ctrl->channels[c].current_c.dis = 1;
			channel_store_c(ctrl, c);

			channel_stop(ctrl, c);
		} else {
			ctrl->channels[c].regs[RW_SAVED_DATA] =
				(uint32_t)(unsigned long)ctrl->
					channels[c].current_d.next;
			/* Load new descriptor.  */
			channel_load_d(ctrl, c);
			saved_data_buf = (uint32_t)(unsigned long)
				ctrl->channels[c].current_d.buf;
		}
	}

	ctrl->channels[c].regs[RW_SAVED_DATA_BUF] = saved_data_buf;
	return len;
}

static inline int channel_in_run(struct fs_dma_ctrl *ctrl, int c)
{
	if (ctrl->channels[c].client->client.pull) {
		ctrl->channels[c].client->client.pull(
			ctrl->channels[c].client->client.opaque);
		return 1;
	} else
		return 0;
}

static uint32_t dma_rinvalid (void *opaque, target_phys_addr_t addr)
{
        struct fs_dma_ctrl *ctrl = opaque;
        CPUState *env = ctrl->env;
        cpu_abort(env, "Unsupported short access. reg=" TARGET_FMT_plx "\n",
                  addr);
        return 0;
}

static uint32_t
dma_readl (void *opaque, target_phys_addr_t addr)
{
        struct fs_dma_ctrl *ctrl = opaque;
	int c;
	uint32_t r = 0;

	/* Make addr relative to this channel and bounded to nr regs.  */
	c = fs_channel(addr);
	addr &= 0xff;
	switch (addr)
	{
		case RW_STAT:
			r = ctrl->channels[c].state & 7;
			r |= ctrl->channels[c].eol << 5;
			r |= ctrl->channels[c].stream_cmd_src << 8;
			break;

		default:
			r = ctrl->channels[c].regs[addr];
			D(printf ("%s c=%d addr=%x\n",
				  __func__, c, addr));
			break;
	}
	return r;
}

static void
dma_winvalid (void *opaque, target_phys_addr_t addr, uint32_t value)
{
        struct fs_dma_ctrl *ctrl = opaque;
        CPUState *env = ctrl->env;
        cpu_abort(env, "Unsupported short access. reg=" TARGET_FMT_plx "\n",
                  addr);
}

static void
dma_update_state(struct fs_dma_ctrl *ctrl, int c)
{
	if ((ctrl->channels[c].regs[RW_CFG] & 1) != 3) {
		if (ctrl->channels[c].regs[RW_CFG] & 2)
			ctrl->channels[c].state = STOPPED;
		if (!(ctrl->channels[c].regs[RW_CFG] & 1))
			ctrl->channels[c].state = RST;
	}
}

static void
dma_writel (void *opaque, target_phys_addr_t addr, uint32_t value)
{
        struct fs_dma_ctrl *ctrl = opaque;
	int c;

        /* Make addr relative to this channel and bounded to nr regs.  */
	c = fs_channel(addr);
        addr &= 0xff;
        switch (addr)
	{
		case RW_DATA:
			ctrl->channels[c].regs[addr] = value;
			break;

		case RW_CFG:
			ctrl->channels[c].regs[addr] = value;
			dma_update_state(ctrl, c);
			break;
		case RW_CMD:
			/* continue.  */
			if (value & ~1)
				printf("Invalid store to ch=%d RW_CMD %x\n",
				       c, value);
			ctrl->channels[c].regs[addr] = value;
			channel_continue(ctrl, c);
			break;

		case RW_SAVED_DATA:
		case RW_SAVED_DATA_BUF:
		case RW_GROUP:
		case RW_GROUP_DOWN:
			ctrl->channels[c].regs[addr] = value;
			break;

		case RW_ACK_INTR:
		case RW_INTR_MASK:
			ctrl->channels[c].regs[addr] = value;
			channel_update_irq(ctrl, c);
			if (addr == RW_ACK_INTR)
				ctrl->channels[c].regs[RW_ACK_INTR] = 0;
			break;

		case RW_STREAM_CMD:
			if (value & ~1023)
				printf("Invalid store to ch=%d "
				       "RW_STREAMCMD %x\n",
				       c, value);
			ctrl->channels[c].regs[addr] = value;
			D(printf("stream_cmd ch=%d\n", c));
			channel_stream_cmd(ctrl, c, value);
			break;

	        default:
			D(printf ("%s c=%d %x %x\n", __func__, c, addr));
			break;
        }
}

static CPUReadMemoryFunc *dma_read[] = {
	&dma_rinvalid,
	&dma_rinvalid,
	&dma_readl,
};

static CPUWriteMemoryFunc *dma_write[] = {
	&dma_winvalid,
	&dma_winvalid,
	&dma_writel,
};

static int etraxfs_dmac_run(void *opaque)
{
	struct fs_dma_ctrl *ctrl = opaque;
	int i;
	int p = 0;

	for (i = 0; 
	     i < ctrl->nr_channels;
	     i++)
	{
		if (ctrl->channels[i].state == RUNNING)
		{
			if (ctrl->channels[i].input) {
				p += channel_in_run(ctrl, i);
			} else {
				p += channel_out_run(ctrl, i);
			}
		}
	}
	return p;
}

int etraxfs_dmac_input(struct etraxfs_dma_client *client, 
		       void *buf, int len, int eop)
{
	return channel_in_process(client->ctrl, client->channel, 
				  buf, len, eop);
}

/* Connect an IRQ line with a channel.  */
void etraxfs_dmac_connect(void *opaque, int c, qemu_irq *line, int input)
{
	struct fs_dma_ctrl *ctrl = opaque;
	ctrl->channels[c].irq = line;
	ctrl->channels[c].input = input;
}

void etraxfs_dmac_connect_client(void *opaque, int c, 
				 struct etraxfs_dma_client *cl)
{
	struct fs_dma_ctrl *ctrl = opaque;
	cl->ctrl = ctrl;
	cl->channel = c;
	ctrl->channels[c].client = cl;
}


static void DMA_run(void *opaque)
{
    struct fs_dma_ctrl *etraxfs_dmac = opaque;
    int p = 1;

    if (vm_running)
        p = etraxfs_dmac_run(etraxfs_dmac);

    if (p)
        qemu_bh_schedule_idle(etraxfs_dmac->bh);
}

void *etraxfs_dmac_init(CPUState *env, 
			target_phys_addr_t base, int nr_channels)
{
	struct fs_dma_ctrl *ctrl = NULL;

	ctrl = qemu_mallocz(sizeof *ctrl);
	if (!ctrl)
		return NULL;

        ctrl->bh = qemu_bh_new(DMA_run, ctrl);

	ctrl->env = env;
	ctrl->nr_channels = nr_channels;
	ctrl->channels = qemu_mallocz(sizeof ctrl->channels[0] * nr_channels);
	if (!ctrl->channels)
		goto err;

	ctrl->map = cpu_register_io_memory(0, dma_read, dma_write, ctrl);
	cpu_register_physical_memory(base, nr_channels * 0x2000, ctrl->map);
	return ctrl;
  err:
	qemu_free(ctrl->channels);
	qemu_free(ctrl);
	return NULL;
}