/*

 * Arm PrimeCell PL061 General Purpose IO with additional

 * Luminary Micro Stellaris bits.

 *

 * Copyright (c) 2007 CodeSourcery.

 * Written by Paul Brook

 *

 * This code is licenced under the GPL.

 */

#include "hw.h"

#include "primecell.h"

//#define DEBUG_PL061 1

#ifdef DEBUG_PL061

#define DPRINTF(fmt, args...) \

do { printf("pl061: " fmt , ##args); } while (0)

#define BADF(fmt, args...) \

do { fprintf(stderr, "pl061: error: " fmt , ##args); exit(1);} while (0)

#else

#define DPRINTF(fmt, args...) do {} while(0)

#define BADF(fmt, args...) \

do { fprintf(stderr, "pl061: error: " fmt , ##args);} while (0)

#endif

static const uint8_t pl061_id[12] =

  { 0x00, 0x00, 0x00, 0x00, 0x61, 0x00, 0x18, 0x01, 0x0d, 0xf0, 0x05, 0xb1 };

typedef struct {

    int locked;

    uint8_t data;

    uint8_t old_data;

    uint8_t dir;

    uint8_t isense;

    uint8_t ibe;

    uint8_t iev;

    uint8_t im;

    uint8_t istate;

    uint8_t afsel;

    uint8_t dr2r;

    uint8_t dr4r;

    uint8_t dr8r;

    uint8_t odr;

    uint8_t pur;

    uint8_t pdr;

    uint8_t slr;

    uint8_t den;

    uint8_t cr;

    uint8_t float_high;

    qemu_irq irq;

    qemu_irq out[8];

} pl061_state;

static void pl061_update(pl061_state *s)

{

    uint8_t changed;

    uint8_t mask;

    uint8_t out;

    int i;

    /* Outputs float high.  */

    /* FIXME: This is board dependent.  */

    out = (s->data & s->dir) | ~s->dir;

    changed = s->old_data ^ out;

    if (!changed)

        return;

    s->old_data = out;

    for (i = 0; i < 8; i++) {

        mask = 1 << i;

        if ((changed & mask) && s->out) {

            DPRINTF("Set output %d = %d\n", i, (out & mask) != 0);

            qemu_set_irq(s->out[i], (out & mask) != 0);

        }

    }

    /* FIXME: Implement input interrupts.  */

}

static uint32_t pl061_read(void *opaque, target_phys_addr_t offset)

{

    pl061_state *s = (pl061_state *)opaque;

    if (offset >= 0xfd0 && offset < 0x1000) {

        return pl061_id[(offset - 0xfd0) >> 2];

    }

    if (offset < 0x400) {

        return s->data & (offset >> 2);

    }

    switch (offset) {

    case 0x400: /* Direction */

        return s->dir;

    case 0x404: /* Interrupt sense */

        return s->isense;

    case 0x408: /* Interrupt both edges */

        return s->ibe;

    case 0x40c: /* Interupt event */

        return s->iev;

    case 0x410: /* Interrupt mask */

        return s->im;

    case 0x414: /* Raw interrupt status */

        return s->istate;

    case 0x418: /* Masked interrupt status */

        return s->istate | s->im;

    case 0x420: /* Alternate function select */

        return s->afsel;

    case 0x500: /* 2mA drive */

        return s->dr2r;

    case 0x504: /* 4mA drive */

        return s->dr4r;

    case 0x508: /* 8mA drive */

        return s->dr8r;

    case 0x50c: /* Open drain */

        return s->odr;

    case 0x510: /* Pull-up */

        return s->pur;

    case 0x514: /* Pull-down */

        return s->pdr;

    case 0x518: /* Slew rate control */

        return s->slr;

    case 0x51c: /* Digital enable */

        return s->den;

    case 0x520: /* Lock */

        return s->locked;

    case 0x524: /* Commit */

        return s->cr;

    default:

        cpu_abort (cpu_single_env, "pl061_read: Bad offset %x\n",

                   (int)offset);

        return 0;

    }

}

static void pl061_write(void *opaque, target_phys_addr_t offset,

                        uint32_t value)

{

    pl061_state *s = (pl061_state *)opaque;

    uint8_t mask;

    if (offset < 0x400) {

        mask = (offset >> 2) & s->dir;

        s->data = (s->data & ~mask) | (value & mask);

        pl061_update(s);

        return;

    }

    switch (offset) {

    case 0x400: /* Direction */

        s->dir = value;

        break;

    case 0x404: /* Interrupt sense */

        s->isense = value;

        break;

    case 0x408: /* Interrupt both edges */

        s->ibe = value;

        break;

    case 0x40c: /* Interupt event */

        s->iev = value;

        break;

    case 0x410: /* Interrupt mask */

        s->im = value;

        break;

    case 0x41c: /* Interrupt clear */

        s->istate &= ~value;

        break;

    case 0x420: /* Alternate function select */

        mask = s->cr;

        s->afsel = (s->afsel & ~mask) | (value & mask);

        break;

    case 0x500: /* 2mA drive */

        s->dr2r = value;

        break;

    case 0x504: /* 4mA drive */

        s->dr4r = value;

        break;

    case 0x508: /* 8mA drive */

        s->dr8r = value;

        break;

    case 0x50c: /* Open drain */

        s->odr = value;

        break;

    case 0x510: /* Pull-up */

        s->pur = value;

        break;

    case 0x514: /* Pull-down */

        s->pdr = value;

        break;

    case 0x518: /* Slew rate control */

        s->slr = value;

        break;

    case 0x51c: /* Digital enable */

        s->den = value;

        break;

    case 0x520: /* Lock */

        s->locked = (value != 0xacce551);

        break;

    case 0x524: /* Commit */

        if (!s->locked)

            s->cr = value;

        break;

    default:

        cpu_abort (cpu_single_env, "pl061_write: Bad offset %x\n",

                   (int)offset);

    }

    pl061_update(s);

}

static void pl061_reset(pl061_state *s)

{

  s->locked = 1;

  s->cr = 0xff;

}

static void pl061_set_irq(void * opaque, int irq, int level)

{

    pl061_state *s = (pl061_state *)opaque;

    uint8_t mask;

    mask = 1 << irq;

    if ((s->dir & mask) == 0) {

        s->data &= ~mask;

        if (level)

            s->data |= mask;

        pl061_update(s);

    }

}

static CPUReadMemoryFunc *pl061_readfn[] = {

   pl061_read,

   pl061_read,

   pl061_read

};

static CPUWriteMemoryFunc *pl061_writefn[] = {

   pl061_write,

   pl061_write,

   pl061_write

};

static void pl061_save(QEMUFile *f, void *opaque)

{

    pl061_state *s = (pl061_state *)opaque;

    qemu_put_be32(f, s->locked);

    qemu_put_be32(f, s->data);

    qemu_put_be32(f, s->old_data);

    qemu_put_be32(f, s->dir);

    qemu_put_be32(f, s->isense);

    qemu_put_be32(f, s->ibe);

    qemu_put_be32(f, s->iev);

    qemu_put_be32(f, s->im);

    qemu_put_be32(f, s->istate);

    qemu_put_be32(f, s->afsel);

    qemu_put_be32(f, s->dr2r);

    qemu_put_be32(f, s->dr4r);

    qemu_put_be32(f, s->dr8r);

    qemu_put_be32(f, s->odr);

    qemu_put_be32(f, s->pur);

    qemu_put_be32(f, s->pdr);

    qemu_put_be32(f, s->slr);

    qemu_put_be32(f, s->den);

    qemu_put_be32(f, s->cr);

    qemu_put_be32(f, s->float_high);

}

static int pl061_load(QEMUFile *f, void *opaque, int version_id)

{

    pl061_state *s = (pl061_state *)opaque;

    if (version_id != 1)

        return -EINVAL;

    s->locked = qemu_get_be32(f);

    s->data = qemu_get_be32(f);

    s->old_data = qemu_get_be32(f);

    s->dir = qemu_get_be32(f);

    s->isense = qemu_get_be32(f);

    s->ibe = qemu_get_be32(f);

    s->iev = qemu_get_be32(f);

    s->im = qemu_get_be32(f);

    s->istate = qemu_get_be32(f);

    s->afsel = qemu_get_be32(f);

    s->dr2r = qemu_get_be32(f);

    s->dr4r = qemu_get_be32(f);

    s->dr8r = qemu_get_be32(f);

    s->odr = qemu_get_be32(f);

    s->pur = qemu_get_be32(f);

    s->pdr = qemu_get_be32(f);

    s->slr = qemu_get_be32(f);

    s->den = qemu_get_be32(f);

    s->cr = qemu_get_be32(f);

    s->float_high = qemu_get_be32(f);

    return 0;

}

/* Returns an array of inputs.  */

qemu_irq *pl061_init(uint32_t base, qemu_irq irq, qemu_irq **out)

{

    int iomemtype;

    pl061_state *s;

    s = (pl061_state *)qemu_mallocz(sizeof(pl061_state));

    iomemtype = cpu_register_io_memory(0, pl061_readfn,

                                       pl061_writefn, s);

    cpu_register_physical_memory(base, 0x00001000, iomemtype);

    s->irq = irq;

    pl061_reset(s);

    if (out)

        *out = s->out;

    register_savevm("pl061_gpio", -1, 1, pl061_save, pl061_load, s);

    return qemu_allocate_irqs(pl061_set_irq, s, 8);

}