Archipelago » qemu

/*

 * TI OMAP DMA gigacell.

 *

 * Copyright (C) 2006-2008 Andrzej Zaborowski  <balrog@zabor.org>

 * Copyright (C) 2007-2008 Lauro Ramos Venancio  <lauro.venancio@indt.org.br>

 *

 * 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, see <http://www.gnu.org/licenses/>.

 */

#include "qemu-common.h"

#include "qemu-timer.h"

#include "omap.h"

#include "irq.h"

#include "soc_dma.h"

struct omap_dma_channel_s {

    /* transfer data */

    int burst[2];

    int pack[2];

    int endian[2];

    int endian_lock[2];

    int translate[2];

    enum omap_dma_port port[2];

    target_phys_addr_t addr[2];

    omap_dma_addressing_t mode[2];

    uint32_t elements;

    uint16_t frames;

    int32_t frame_index[2];

    int16_t element_index[2];

    int data_type;

    /* transfer type */

    int transparent_copy;

    int constant_fill;

    uint32_t color;

    int prefetch;

    /* auto init and linked channel data */

    int end_prog;

    int repeat;

    int auto_init;

    int link_enabled;

    int link_next_ch;

    /* interruption data */

    int interrupts;

    int status;

    int cstatus;

    /* state data */

    int active;

    int enable;

    int sync;

    int src_sync;

    int pending_request;

    int waiting_end_prog;

    uint16_t cpc;

    int set_update;

    /* sync type */

    int fs;

    int bs;

    /* compatibility */

    int omap_3_1_compatible_disable;

    qemu_irq irq;

    struct omap_dma_channel_s *sibling;

    struct omap_dma_reg_set_s {

        target_phys_addr_t src, dest;

        int frame;

        int element;

        int pck_element;

        int frame_delta[2];

        int elem_delta[2];

        int frames;

        int elements;

        int pck_elements;

    } active_set;

    struct soc_dma_ch_s *dma;

    /* unused parameters */

    int write_mode;

    int priority;

    int interleave_disabled;

    int type;

    int suspend;

    int buf_disable;

};

struct omap_dma_s {

    struct soc_dma_s *dma;

    struct omap_mpu_state_s *mpu;

    omap_clk clk;

    qemu_irq irq[4];

    void (*intr_update)(struct omap_dma_s *s);

    enum omap_dma_model model;

    int omap_3_1_mapping_disabled;

    uint32_t gcr;

    uint32_t ocp;

    uint32_t caps[5];

    uint32_t irqen[4];

    uint32_t irqstat[4];

    int chans;

    struct omap_dma_channel_s ch[32];

    struct omap_dma_lcd_channel_s lcd_ch;

};

/* Interrupts */

#define TIMEOUT_INTR    (1 << 0)

#define EVENT_DROP_INTR (1 << 1)

#define HALF_FRAME_INTR (1 << 2)

#define END_FRAME_INTR  (1 << 3)

#define LAST_FRAME_INTR (1 << 4)

#define END_BLOCK_INTR  (1 << 5)

#define SYNC            (1 << 6)

#define END_PKT_INTR        (1 << 7)

#define TRANS_ERR_INTR        (1 << 8)

#define MISALIGN_INTR        (1 << 11)

static inline void omap_dma_interrupts_update(struct omap_dma_s *s)

{

    return s->intr_update(s);

}

static void omap_dma_channel_load(struct omap_dma_channel_s *ch)

{

    struct omap_dma_reg_set_s *a = &ch->active_set;

    int i, normal;

    int omap_3_1 = !ch->omap_3_1_compatible_disable;

    /*

     * TODO: verify address ranges and alignment

     * TODO: port endianness

     */

    a->src = ch->addr[0];

    a->dest = ch->addr[1];

    a->frames = ch->frames;

    a->elements = ch->elements;

    a->pck_elements = ch->frame_index[!ch->src_sync];

    a->frame = 0;

    a->element = 0;

    a->pck_element = 0;

    if (unlikely(!ch->elements || !ch->frames)) {

        printf("%s: bad DMA request\n", __FUNCTION__);

        return;

    }

    for (i = 0; i < 2; i ++)

        switch (ch->mode[i]) {

        case constant:

            a->elem_delta[i] = 0;

            a->frame_delta[i] = 0;

            break;

        case post_incremented:

            a->elem_delta[i] = ch->data_type;

            a->frame_delta[i] = 0;

            break;

        case single_index:

            a->elem_delta[i] = ch->data_type +

                    ch->element_index[omap_3_1 ? 0 : i] - 1;

            a->frame_delta[i] = 0;

            break;

        case double_index:

            a->elem_delta[i] = ch->data_type +

                    ch->element_index[omap_3_1 ? 0 : i] - 1;

            a->frame_delta[i] = ch->frame_index[omap_3_1 ? 0 : i] -

                    ch->element_index[omap_3_1 ? 0 : i];

            break;

        default:

            break;

        }

    normal = !ch->transparent_copy && !ch->constant_fill &&

            /* FIFO is big-endian so either (ch->endian[n] == 1) OR

             * (ch->endian_lock[n] == 1) mean no endianism conversion.  */

            (ch->endian[0] | ch->endian_lock[0]) ==

            (ch->endian[1] | ch->endian_lock[1]);

    for (i = 0; i < 2; i ++) {

        /* TODO: for a->frame_delta[i] > 0 still use the fast path, just

         * limit min_elems in omap_dma_transfer_setup to the nearest frame

         * end.  */

        if (!a->elem_delta[i] && normal &&

                        (a->frames == 1 || !a->frame_delta[i]))

            ch->dma->type[i] = soc_dma_access_const;

        else if (a->elem_delta[i] == ch->data_type && normal &&

                        (a->frames == 1 || !a->frame_delta[i]))

            ch->dma->type[i] = soc_dma_access_linear;

        else

            ch->dma->type[i] = soc_dma_access_other;

        ch->dma->vaddr[i] = ch->addr[i];

    }

    soc_dma_ch_update(ch->dma);

}

static void omap_dma_activate_channel(struct omap_dma_s *s,

                struct omap_dma_channel_s *ch)

{

    if (!ch->active) {

        if (ch->set_update) {

            /* It's not clear when the active set is supposed to be

             * loaded from registers.  We're already loading it when the

             * channel is enabled, and for some guests this is not enough

             * but that may be also because of a race condition (no

             * delays in qemu) in the guest code, which we're just

             * working around here.  */

            omap_dma_channel_load(ch);

            ch->set_update = 0;

        }

        ch->active = 1;

        soc_dma_set_request(ch->dma, 1);

        if (ch->sync)

            ch->status |= SYNC;

    }

}

static void omap_dma_deactivate_channel(struct omap_dma_s *s,

                struct omap_dma_channel_s *ch)

{

    /* Update cpc */

    ch->cpc = ch->active_set.dest & 0xffff;

    if (ch->pending_request && !ch->waiting_end_prog && ch->enable) {

        /* Don't deactivate the channel */

        ch->pending_request = 0;

        return;

    }

    /* Don't deactive the channel if it is synchronized and the DMA request is

       active */

    if (ch->sync && ch->enable && (s->dma->drqbmp & (1 << ch->sync)))

        return;

    if (ch->active) {

        ch->active = 0;

        ch->status &= ~SYNC;

        soc_dma_set_request(ch->dma, 0);

    }

}

static void omap_dma_enable_channel(struct omap_dma_s *s,

                struct omap_dma_channel_s *ch)

{

    if (!ch->enable) {

        ch->enable = 1;

        ch->waiting_end_prog = 0;

        omap_dma_channel_load(ch);

        /* TODO: theoretically if ch->sync && ch->prefetch &&

         * !s->dma->drqbmp[ch->sync], we should also activate and fetch

         * from source and then stall until signalled.  */

        if ((!ch->sync) || (s->dma->drqbmp & (1 << ch->sync)))

            omap_dma_activate_channel(s, ch);

    }

}

static void omap_dma_disable_channel(struct omap_dma_s *s,

                struct omap_dma_channel_s *ch)

{

    if (ch->enable) {

        ch->enable = 0;

        /* Discard any pending request */

        ch->pending_request = 0;

        omap_dma_deactivate_channel(s, ch);

    }

}

static void omap_dma_channel_end_prog(struct omap_dma_s *s,

                struct omap_dma_channel_s *ch)

{

    if (ch->waiting_end_prog) {

        ch->waiting_end_prog = 0;

        if (!ch->sync || ch->pending_request) {

            ch->pending_request = 0;

            omap_dma_activate_channel(s, ch);

        }

    }

}

static void omap_dma_interrupts_3_1_update(struct omap_dma_s *s)

{

    struct omap_dma_channel_s *ch = s->ch;

    /* First three interrupts are shared between two channels each. */

    if (ch[0].status | ch[6].status)

        qemu_irq_raise(ch[0].irq);

    if (ch[1].status | ch[7].status)

        qemu_irq_raise(ch[1].irq);

    if (ch[2].status | ch[8].status)

        qemu_irq_raise(ch[2].irq);

    if (ch[3].status)

        qemu_irq_raise(ch[3].irq);

    if (ch[4].status)

        qemu_irq_raise(ch[4].irq);

    if (ch[5].status)

        qemu_irq_raise(ch[5].irq);

}

static void omap_dma_interrupts_3_2_update(struct omap_dma_s *s)

{

    struct omap_dma_channel_s *ch = s->ch;

    int i;

    for (i = s->chans; i; ch ++, i --)

        if (ch->status)

            qemu_irq_raise(ch->irq);

}

static void omap_dma_enable_3_1_mapping(struct omap_dma_s *s)

{

    s->omap_3_1_mapping_disabled = 0;

    s->chans = 9;

    s->intr_update = omap_dma_interrupts_3_1_update;

}

static void omap_dma_disable_3_1_mapping(struct omap_dma_s *s)

{

    s->omap_3_1_mapping_disabled = 1;

    s->chans = 16;

    s->intr_update = omap_dma_interrupts_3_2_update;

}

static void omap_dma_process_request(struct omap_dma_s *s, int request)

{

    int channel;

    int drop_event = 0;

    struct omap_dma_channel_s *ch = s->ch;

    for (channel = 0; channel < s->chans; channel ++, ch ++) {

        if (ch->enable && ch->sync == request) {

            if (!ch->active)

                omap_dma_activate_channel(s, ch);

            else if (!ch->pending_request)

                ch->pending_request = 1;

            else {

                /* Request collision */

                /* Second request received while processing other request */

                ch->status |= EVENT_DROP_INTR;

                drop_event = 1;

            }

        }

    }

    if (drop_event)

        omap_dma_interrupts_update(s);

}

static void omap_dma_transfer_generic(struct soc_dma_ch_s *dma)

{

    uint8_t value[4];

    struct omap_dma_channel_s *ch = dma->opaque;

    struct omap_dma_reg_set_s *a = &ch->active_set;

    int bytes = dma->bytes;

#ifdef MULTI_REQ

    uint16_t status = ch->status;

#endif

    do {

        /* Transfer a single element */

        /* FIXME: check the endianness */

        if (!ch->constant_fill)

            cpu_physical_memory_read(a->src, value, ch->data_type);

        else

            *(uint32_t *) value = ch->color;

        if (!ch->transparent_copy || *(uint32_t *) value != ch->color)

            cpu_physical_memory_write(a->dest, value, ch->data_type);

        a->src += a->elem_delta[0];

        a->dest += a->elem_delta[1];

        a->element ++;

#ifndef MULTI_REQ

        if (a->element == a->elements) {

            /* End of Frame */

            a->element = 0;

            a->src += a->frame_delta[0];

            a->dest += a->frame_delta[1];

            a->frame ++;

            /* If the channel is async, update cpc */

            if (!ch->sync)

                ch->cpc = a->dest & 0xffff;

        }

    } while ((bytes -= ch->data_type));

#else

        /* If the channel is element synchronized, deactivate it */

        if (ch->sync && !ch->fs && !ch->bs)

            omap_dma_deactivate_channel(s, ch);

        /* If it is the last frame, set the LAST_FRAME interrupt */

        if (a->element == 1 && a->frame == a->frames - 1)

            if (ch->interrupts & LAST_FRAME_INTR)

                ch->status |= LAST_FRAME_INTR;

        /* If the half of the frame was reached, set the HALF_FRAME

           interrupt */

        if (a->element == (a->elements >> 1))

            if (ch->interrupts & HALF_FRAME_INTR)

                ch->status |= HALF_FRAME_INTR;

        if (ch->fs && ch->bs) {

            a->pck_element ++;

            /* Check if a full packet has beed transferred.  */

            if (a->pck_element == a->pck_elements) {

                a->pck_element = 0;

                /* Set the END_PKT interrupt */

                if ((ch->interrupts & END_PKT_INTR) && !ch->src_sync)

                    ch->status |= END_PKT_INTR;

                /* If the channel is packet-synchronized, deactivate it */

                if (ch->sync)

                    omap_dma_deactivate_channel(s, ch);

            }

        }

        if (a->element == a->elements) {

            /* End of Frame */

            a->element = 0;

            a->src += a->frame_delta[0];

            a->dest += a->frame_delta[1];

            a->frame ++;

            /* If the channel is frame synchronized, deactivate it */

            if (ch->sync && ch->fs && !ch->bs)

                omap_dma_deactivate_channel(s, ch);

            /* If the channel is async, update cpc */

            if (!ch->sync)

                ch->cpc = a->dest & 0xffff;

            /* Set the END_FRAME interrupt */

            if (ch->interrupts & END_FRAME_INTR)

                ch->status |= END_FRAME_INTR;

            if (a->frame == a->frames) {

                /* End of Block */

                /* Disable the channel */

                if (ch->omap_3_1_compatible_disable) {

                    omap_dma_disable_channel(s, ch);

                    if (ch->link_enabled)

                        omap_dma_enable_channel(s,

                                        &s->ch[ch->link_next_ch]);

                } else {

                    if (!ch->auto_init)

                        omap_dma_disable_channel(s, ch);

                    else if (ch->repeat || ch->end_prog)

                        omap_dma_channel_load(ch);

                    else {

                        ch->waiting_end_prog = 1;

                        omap_dma_deactivate_channel(s, ch);

                    }

                }

                if (ch->interrupts & END_BLOCK_INTR)

                    ch->status |= END_BLOCK_INTR;

            }

        }

    } while (status == ch->status && ch->active);

    omap_dma_interrupts_update(s);

#endif

}

enum {

    omap_dma_intr_element_sync,

    omap_dma_intr_last_frame,

    omap_dma_intr_half_frame,

    omap_dma_intr_frame,

    omap_dma_intr_frame_sync,

    omap_dma_intr_packet,

    omap_dma_intr_packet_sync,

    omap_dma_intr_block,

    __omap_dma_intr_last,

};

static void omap_dma_transfer_setup(struct soc_dma_ch_s *dma)

{

    struct omap_dma_port_if_s *src_p, *dest_p;

    struct omap_dma_reg_set_s *a;

    struct omap_dma_channel_s *ch = dma->opaque;

    struct omap_dma_s *s = dma->dma->opaque;

    int frames, min_elems, elements[__omap_dma_intr_last];

    a = &ch->active_set;

    src_p = &s->mpu->port[ch->port[0]];

    dest_p = &s->mpu->port[ch->port[1]];

    if ((!ch->constant_fill && !src_p->addr_valid(s->mpu, a->src)) ||

                    (!dest_p->addr_valid(s->mpu, a->dest))) {

#if 0

        /* Bus time-out */

        if (ch->interrupts & TIMEOUT_INTR)

            ch->status |= TIMEOUT_INTR;

        omap_dma_deactivate_channel(s, ch);

        continue;

#endif

        printf("%s: Bus time-out in DMA%i operation\n",

                        __FUNCTION__, dma->num);

    }

    min_elems = INT_MAX;

    /* Check all the conditions that terminate the transfer starting

     * with those that can occur the soonest.  */

#define INTR_CHECK(cond, id, nelements)        \

    if (cond) {                        \

        elements[id] = nelements;        \

        if (elements[id] < min_elems)        \

            min_elems = elements[id];        \

    } else                                \

        elements[id] = INT_MAX;

    /* Elements */

    INTR_CHECK(

                    ch->sync && !ch->fs && !ch->bs,

                    omap_dma_intr_element_sync,

                    1)

    /* Frames */

    /* TODO: for transfers where entire frames can be read and written

     * using memcpy() but a->frame_delta is non-zero, try to still do

     * transfers using soc_dma but limit min_elems to a->elements - ...

     * See also the TODO in omap_dma_channel_load.  */

    INTR_CHECK(

                    (ch->interrupts & LAST_FRAME_INTR) &&

                    ((a->frame < a->frames - 1) || !a->element),

                    omap_dma_intr_last_frame,

                    (a->frames - a->frame - 2) * a->elements +

                    (a->elements - a->element + 1))

    INTR_CHECK(

                    ch->interrupts & HALF_FRAME_INTR,

                    omap_dma_intr_half_frame,

                    (a->elements >> 1) +

                    (a->element >= (a->elements >> 1) ? a->elements : 0) -

                    a->element)

    INTR_CHECK(

                    ch->sync && ch->fs && (ch->interrupts & END_FRAME_INTR),

                    omap_dma_intr_frame,

                    a->elements - a->element)

    INTR_CHECK(

                    ch->sync && ch->fs && !ch->bs,

                    omap_dma_intr_frame_sync,

                    a->elements - a->element)

    /* Packets */

    INTR_CHECK(

                    ch->fs && ch->bs &&

                    (ch->interrupts & END_PKT_INTR) && !ch->src_sync,

                    omap_dma_intr_packet,

                    a->pck_elements - a->pck_element)

    INTR_CHECK(

                    ch->fs && ch->bs && ch->sync,

                    omap_dma_intr_packet_sync,

                    a->pck_elements - a->pck_element)

    /* Blocks */

    INTR_CHECK(

                    1,

                    omap_dma_intr_block,

                    (a->frames - a->frame - 1) * a->elements +

                    (a->elements - a->element))

    dma->bytes = min_elems * ch->data_type;

    /* Set appropriate interrupts and/or deactivate channels */

#ifdef MULTI_REQ

    /* TODO: should all of this only be done if dma->update, and otherwise

     * inside omap_dma_transfer_generic below - check what's faster.  */

    if (dma->update) {

#endif

        /* If the channel is element synchronized, deactivate it */

        if (min_elems == elements[omap_dma_intr_element_sync])

            omap_dma_deactivate_channel(s, ch);

        /* If it is the last frame, set the LAST_FRAME interrupt */

        if (min_elems == elements[omap_dma_intr_last_frame])

            ch->status |= LAST_FRAME_INTR;

        /* If exactly half of the frame was reached, set the HALF_FRAME

           interrupt */

        if (min_elems == elements[omap_dma_intr_half_frame])

            ch->status |= HALF_FRAME_INTR;

        /* If a full packet has been transferred, set the END_PKT interrupt */

        if (min_elems == elements[omap_dma_intr_packet])

            ch->status |= END_PKT_INTR;

        /* If the channel is packet-synchronized, deactivate it */

        if (min_elems == elements[omap_dma_intr_packet_sync])

            omap_dma_deactivate_channel(s, ch);

        /* If the channel is frame synchronized, deactivate it */

        if (min_elems == elements[omap_dma_intr_frame_sync])

            omap_dma_deactivate_channel(s, ch);

        /* Set the END_FRAME interrupt */

        if (min_elems == elements[omap_dma_intr_frame])

            ch->status |= END_FRAME_INTR;

        if (min_elems == elements[omap_dma_intr_block]) {

            /* End of Block */

            /* Disable the channel */

            if (ch->omap_3_1_compatible_disable) {

                omap_dma_disable_channel(s, ch);

                if (ch->link_enabled)

                    omap_dma_enable_channel(s, &s->ch[ch->link_next_ch]);

            } else {

                if (!ch->auto_init)

                    omap_dma_disable_channel(s, ch);

                else if (ch->repeat || ch->end_prog)

                    omap_dma_channel_load(ch);

                else {

                    ch->waiting_end_prog = 1;

                    omap_dma_deactivate_channel(s, ch);

                }

            }

            if (ch->interrupts & END_BLOCK_INTR)

                ch->status |= END_BLOCK_INTR;

        }

        /* Update packet number */

        if (ch->fs && ch->bs) {

            a->pck_element += min_elems;

            a->pck_element %= a->pck_elements;

        }

        /* TODO: check if we really need to update anything here or perhaps we

         * can skip part of this.  */

#ifndef MULTI_REQ

        if (dma->update) {

#endif

            a->element += min_elems;

            frames = a->element / a->elements;

            a->element = a->element % a->elements;

            a->frame += frames;

            a->src += min_elems * a->elem_delta[0] + frames * a->frame_delta[0];

            a->dest += min_elems * a->elem_delta[1] + frames * a->frame_delta[1];

            /* If the channel is async, update cpc */

            if (!ch->sync && frames)

                ch->cpc = a->dest & 0xffff;

            /* TODO: if the destination port is IMIF or EMIFF, set the dirty

             * bits on it.  */

#ifndef MULTI_REQ

        }

#else

    }

#endif

    omap_dma_interrupts_update(s);

}

void omap_dma_reset(struct soc_dma_s *dma)

{

    int i;

    struct omap_dma_s *s = dma->opaque;

    soc_dma_reset(s->dma);

    if (s->model < omap_dma_4)

        s->gcr = 0x0004;

    else

        s->gcr = 0x00010010;

    s->ocp = 0x00000000;

    memset(&s->irqstat, 0, sizeof(s->irqstat));

    memset(&s->irqen, 0, sizeof(s->irqen));

    s->lcd_ch.src = emiff;

    s->lcd_ch.condition = 0;

    s->lcd_ch.interrupts = 0;

    s->lcd_ch.dual = 0;

    if (s->model < omap_dma_4)

        omap_dma_enable_3_1_mapping(s);

    for (i = 0; i < s->chans; i ++) {

        s->ch[i].suspend = 0;

        s->ch[i].prefetch = 0;

        s->ch[i].buf_disable = 0;

        s->ch[i].src_sync = 0;

        memset(&s->ch[i].burst, 0, sizeof(s->ch[i].burst));

        memset(&s->ch[i].port, 0, sizeof(s->ch[i].port));

        memset(&s->ch[i].mode, 0, sizeof(s->ch[i].mode));

        memset(&s->ch[i].frame_index, 0, sizeof(s->ch[i].frame_index));

        memset(&s->ch[i].element_index, 0, sizeof(s->ch[i].element_index));

        memset(&s->ch[i].endian, 0, sizeof(s->ch[i].endian));

        memset(&s->ch[i].endian_lock, 0, sizeof(s->ch[i].endian_lock));

        memset(&s->ch[i].translate, 0, sizeof(s->ch[i].translate));

        s->ch[i].write_mode = 0;

        s->ch[i].data_type = 0;

        s->ch[i].transparent_copy = 0;

        s->ch[i].constant_fill = 0;

        s->ch[i].color = 0x00000000;

        s->ch[i].end_prog = 0;

        s->ch[i].repeat = 0;

        s->ch[i].auto_init = 0;

        s->ch[i].link_enabled = 0;

        if (s->model < omap_dma_4)

            s->ch[i].interrupts = 0x0003;

        else

            s->ch[i].interrupts = 0x0000;

        s->ch[i].status = 0;

        s->ch[i].cstatus = 0;

        s->ch[i].active = 0;

        s->ch[i].enable = 0;

        s->ch[i].sync = 0;

        s->ch[i].pending_request = 0;

        s->ch[i].waiting_end_prog = 0;

        s->ch[i].cpc = 0x0000;

        s->ch[i].fs = 0;

        s->ch[i].bs = 0;

        s->ch[i].omap_3_1_compatible_disable = 0;

        memset(&s->ch[i].active_set, 0, sizeof(s->ch[i].active_set));

        s->ch[i].priority = 0;

        s->ch[i].interleave_disabled = 0;

        s->ch[i].type = 0;

    }

}

static int omap_dma_ch_reg_read(struct omap_dma_s *s,

                struct omap_dma_channel_s *ch, int reg, uint16_t *value)

{

    switch (reg) {

    case 0x00:        /* SYS_DMA_CSDP_CH0 */

        *value = (ch->burst[1] << 14) |

                (ch->pack[1] << 13) |

                (ch->port[1] << 9) |

                (ch->burst[0] << 7) |

                (ch->pack[0] << 6) |

                (ch->port[0] << 2) |

                (ch->data_type >> 1);

        break;

    case 0x02:        /* SYS_DMA_CCR_CH0 */

        if (s->model <= omap_dma_3_1)

            *value = 0 << 10;                        /* FIFO_FLUSH reads as 0 */

        else

            *value = ch->omap_3_1_compatible_disable << 10;

        *value |= (ch->mode[1] << 14) |

                (ch->mode[0] << 12) |

                (ch->end_prog << 11) |

                (ch->repeat << 9) |

                (ch->auto_init << 8) |

                (ch->enable << 7) |

                (ch->priority << 6) |

                (ch->fs << 5) | ch->sync;

        break;

    case 0x04:        /* SYS_DMA_CICR_CH0 */

        *value = ch->interrupts;

        break;

    case 0x06:        /* SYS_DMA_CSR_CH0 */

        *value = ch->status;

        ch->status &= SYNC;

        if (!ch->omap_3_1_compatible_disable && ch->sibling) {

            *value |= (ch->sibling->status & 0x3f) << 6;

            ch->sibling->status &= SYNC;

        }

        qemu_irq_lower(ch->irq);

        break;

    case 0x08:        /* SYS_DMA_CSSA_L_CH0 */

        *value = ch->addr[0] & 0x0000ffff;

        break;

    case 0x0a:        /* SYS_DMA_CSSA_U_CH0 */

        *value = ch->addr[0] >> 16;

        break;

    case 0x0c:        /* SYS_DMA_CDSA_L_CH0 */

        *value = ch->addr[1] & 0x0000ffff;

        break;

    case 0x0e:        /* SYS_DMA_CDSA_U_CH0 */

        *value = ch->addr[1] >> 16;

        break;

    case 0x10:        /* SYS_DMA_CEN_CH0 */

        *value = ch->elements;

        break;

    case 0x12:        /* SYS_DMA_CFN_CH0 */

        *value = ch->frames;

        break;

    case 0x14:        /* SYS_DMA_CFI_CH0 */

        *value = ch->frame_index[0];

        break;

    case 0x16:        /* SYS_DMA_CEI_CH0 */

        *value = ch->element_index[0];

        break;

    case 0x18:        /* SYS_DMA_CPC_CH0 or DMA_CSAC */

        if (ch->omap_3_1_compatible_disable)

            *value = ch->active_set.src & 0xffff;        /* CSAC */

        else

            *value = ch->cpc;

        break;

    case 0x1a:        /* DMA_CDAC */

        *value = ch->active_set.dest & 0xffff;        /* CDAC */

        break;

    case 0x1c:        /* DMA_CDEI */

        *value = ch->element_index[1];

        break;

    case 0x1e:        /* DMA_CDFI */

        *value = ch->frame_index[1];

        break;

    case 0x20:        /* DMA_COLOR_L */

        *value = ch->color & 0xffff;

        break;

    case 0x22:        /* DMA_COLOR_U */

        *value = ch->color >> 16;

        break;

    case 0x24:        /* DMA_CCR2 */

        *value = (ch->bs << 2) |

                (ch->transparent_copy << 1) |

                ch->constant_fill;

        break;

    case 0x28:        /* DMA_CLNK_CTRL */

        *value = (ch->link_enabled << 15) |

                (ch->link_next_ch & 0xf);

        break;

    case 0x2a:        /* DMA_LCH_CTRL */

        *value = (ch->interleave_disabled << 15) |

                ch->type;

        break;

    default:

        return 1;

    }

    return 0;

}

static int omap_dma_ch_reg_write(struct omap_dma_s *s,

                struct omap_dma_channel_s *ch, int reg, uint16_t value)

{

    switch (reg) {

    case 0x00:        /* SYS_DMA_CSDP_CH0 */

        ch->burst[1] = (value & 0xc000) >> 14;

        ch->pack[1] = (value & 0x2000) >> 13;

        ch->port[1] = (enum omap_dma_port) ((value & 0x1e00) >> 9);

        ch->burst[0] = (value & 0x0180) >> 7;

        ch->pack[0] = (value & 0x0040) >> 6;

        ch->port[0] = (enum omap_dma_port) ((value & 0x003c) >> 2);

        ch->data_type = 1 << (value & 3);

        if (ch->port[0] >= __omap_dma_port_last)

            printf("%s: invalid DMA port %i\n", __FUNCTION__,

                            ch->port[0]);

        if (ch->port[1] >= __omap_dma_port_last)

            printf("%s: invalid DMA port %i\n", __FUNCTION__,

                            ch->port[1]);

        if ((value & 3) == 3)

            printf("%s: bad data_type for DMA channel\n", __FUNCTION__);

        break;

    case 0x02:        /* SYS_DMA_CCR_CH0 */

        ch->mode[1] = (omap_dma_addressing_t) ((value & 0xc000) >> 14);

        ch->mode[0] = (omap_dma_addressing_t) ((value & 0x3000) >> 12);

        ch->end_prog = (value & 0x0800) >> 11;