/*

 * Intel XScale PXA255/270 GPIO controller emulation.

 *

 * Copyright (c) 2006 Openedhand Ltd.

 * Written by Andrzej Zaborowski <balrog@zabor.org>

 *

 * This code is licensed under the GPL.

 */

#include "hw.h"

#include "pxa.h"

#define PXA2XX_GPIO_BANKS	4

struct pxa2xx_gpio_info_s {

    qemu_irq *pic;

    int lines;

    CPUState *cpu_env;

    qemu_irq *in;

    /* XXX: GNU C vectors are more suitable */

    uint32_t ilevel[PXA2XX_GPIO_BANKS];

    uint32_t olevel[PXA2XX_GPIO_BANKS];

    uint32_t dir[PXA2XX_GPIO_BANKS];

    uint32_t rising[PXA2XX_GPIO_BANKS];

    uint32_t falling[PXA2XX_GPIO_BANKS];

    uint32_t status[PXA2XX_GPIO_BANKS];

    uint32_t gpsr[PXA2XX_GPIO_BANKS];

    uint32_t gafr[PXA2XX_GPIO_BANKS * 2];

    uint32_t prev_level[PXA2XX_GPIO_BANKS];

    qemu_irq handler[PXA2XX_GPIO_BANKS * 32];

    qemu_irq read_notify;

};

static struct {

    enum {

        GPIO_NONE,

        GPLR,

        GPSR,

        GPCR,

        GPDR,

        GRER,

        GFER,

        GEDR,

        GAFR_L,

        GAFR_U,

    } reg;

    int bank;

} pxa2xx_gpio_regs[0x200] = {

    [0 ... 0x1ff] = { GPIO_NONE, 0 },

#define PXA2XX_REG(reg, a0, a1, a2, a3)	\

    [a0] = { reg, 0 }, [a1] = { reg, 1 }, [a2] = { reg, 2 }, [a3] = { reg, 3 },

    PXA2XX_REG(GPLR, 0x000, 0x004, 0x008, 0x100)

    PXA2XX_REG(GPSR, 0x018, 0x01c, 0x020, 0x118)

    PXA2XX_REG(GPCR, 0x024, 0x028, 0x02c, 0x124)

    PXA2XX_REG(GPDR, 0x00c, 0x010, 0x014, 0x10c)

    PXA2XX_REG(GRER, 0x030, 0x034, 0x038, 0x130)

    PXA2XX_REG(GFER, 0x03c, 0x040, 0x044, 0x13c)

    PXA2XX_REG(GEDR, 0x048, 0x04c, 0x050, 0x148)

    PXA2XX_REG(GAFR_L, 0x054, 0x05c, 0x064, 0x06c)

    PXA2XX_REG(GAFR_U, 0x058, 0x060, 0x068, 0x070)

};

static void pxa2xx_gpio_irq_update(struct pxa2xx_gpio_info_s *s)

{

    if (s->status[0] & (1 << 0))

        qemu_irq_raise(s->pic[PXA2XX_PIC_GPIO_0]);

    else

        qemu_irq_lower(s->pic[PXA2XX_PIC_GPIO_0]);

    if (s->status[0] & (1 << 1))

        qemu_irq_raise(s->pic[PXA2XX_PIC_GPIO_1]);

    else

        qemu_irq_lower(s->pic[PXA2XX_PIC_GPIO_1]);

    if ((s->status[0] & ~3) | s->status[1] | s->status[2] | s->status[3])

        qemu_irq_raise(s->pic[PXA2XX_PIC_GPIO_X]);

    else

        qemu_irq_lower(s->pic[PXA2XX_PIC_GPIO_X]);

}

/* Bitmap of pins used as standby and sleep wake-up sources.  */

static const int pxa2xx_gpio_wake[PXA2XX_GPIO_BANKS] = {

    0x8003fe1b, 0x002001fc, 0xec080000, 0x0012007f,

};

static void pxa2xx_gpio_set(void *opaque, int line, int level)

{

    struct pxa2xx_gpio_info_s *s = (struct pxa2xx_gpio_info_s *) opaque;

    int bank;

    uint32_t mask;

    if (line >= s->lines) {

        printf("%s: No GPIO pin %i\n", __FUNCTION__, line);

        return;

    }

    bank = line >> 5;

    mask = 1 << (line & 31);

    if (level) {

        s->status[bank] |= s->rising[bank] & mask &

                ~s->ilevel[bank] & ~s->dir[bank];

        s->ilevel[bank] |= mask;

    } else {

        s->status[bank] |= s->falling[bank] & mask &

                s->ilevel[bank] & ~s->dir[bank];

        s->ilevel[bank] &= ~mask;

    }

    if (s->status[bank] & mask)

        pxa2xx_gpio_irq_update(s);

    /* Wake-up GPIOs */

    if (s->cpu_env->halted && (mask & ~s->dir[bank] & pxa2xx_gpio_wake[bank]))

        cpu_interrupt(s->cpu_env, CPU_INTERRUPT_EXITTB);

}

static void pxa2xx_gpio_handler_update(struct pxa2xx_gpio_info_s *s) {

    uint32_t level, diff;

    int i, bit, line;

    for (i = 0; i < PXA2XX_GPIO_BANKS; i ++) {

        level = s->olevel[i] & s->dir[i];

        for (diff = s->prev_level[i] ^ level; diff; diff ^= 1 << bit) {

            bit = ffs(diff) - 1;

            line = bit + 32 * i;

            qemu_set_irq(s->handler[line], (level >> bit) & 1);

        }

        s->prev_level[i] = level;

    }

}

static uint32_t pxa2xx_gpio_read(void *opaque, target_phys_addr_t offset)

{

    struct pxa2xx_gpio_info_s *s = (struct pxa2xx_gpio_info_s *) opaque;

    uint32_t ret;

    int bank;

    if (offset >= 0x200)

        return 0;

    bank = pxa2xx_gpio_regs[offset].bank;

    switch (pxa2xx_gpio_regs[offset].reg) {

    case GPDR:		/* GPIO Pin-Direction registers */

        return s->dir[bank];

    case GPSR:		/* GPIO Pin-Output Set registers */

        printf("%s: Read from a write-only register " REG_FMT "\n",

                        __FUNCTION__, offset);

        return s->gpsr[bank];	/* Return last written value.  */

    case GPCR:		/* GPIO Pin-Output Clear registers */

        printf("%s: Read from a write-only register " REG_FMT "\n",

                        __FUNCTION__, offset);

        return 31337;		/* Specified as unpredictable in the docs.  */

    case GRER:		/* GPIO Rising-Edge Detect Enable registers */

        return s->rising[bank];

    case GFER:		/* GPIO Falling-Edge Detect Enable registers */

        return s->falling[bank];

    case GAFR_L:	/* GPIO Alternate Function registers */

        return s->gafr[bank * 2];

    case GAFR_U:	/* GPIO Alternate Function registers */

        return s->gafr[bank * 2 + 1];

    case GPLR:		/* GPIO Pin-Level registers */

        ret = (s->olevel[bank] & s->dir[bank]) |

                (s->ilevel[bank] & ~s->dir[bank]);

        qemu_irq_raise(s->read_notify);

        return ret;

    case GEDR:		/* GPIO Edge Detect Status registers */

        return s->status[bank];

    default:

        cpu_abort(cpu_single_env,

                "%s: Bad offset " REG_FMT "\n", __FUNCTION__, offset);

    }

    return 0;

}

static void pxa2xx_gpio_write(void *opaque,

                target_phys_addr_t offset, uint32_t value)

{

    struct pxa2xx_gpio_info_s *s = (struct pxa2xx_gpio_info_s *) opaque;

    int bank;

    if (offset >= 0x200)

        return;

    bank = pxa2xx_gpio_regs[offset].bank;

    switch (pxa2xx_gpio_regs[offset].reg) {

    case GPDR:		/* GPIO Pin-Direction registers */

        s->dir[bank] = value;

        pxa2xx_gpio_handler_update(s);

        break;

    case GPSR:		/* GPIO Pin-Output Set registers */

        s->olevel[bank] |= value;

        pxa2xx_gpio_handler_update(s);

        s->gpsr[bank] = value;

        break;

    case GPCR:		/* GPIO Pin-Output Clear registers */

        s->olevel[bank] &= ~value;

        pxa2xx_gpio_handler_update(s);

        break;

    case GRER:		/* GPIO Rising-Edge Detect Enable registers */

        s->rising[bank] = value;

        break;

    case GFER:		/* GPIO Falling-Edge Detect Enable registers */

        s->falling[bank] = value;

        break;

    case GAFR_L:	/* GPIO Alternate Function registers */

        s->gafr[bank * 2] = value;

        break;

    case GAFR_U:	/* GPIO Alternate Function registers */

        s->gafr[bank * 2 + 1] = value;

        break;

    case GEDR:		/* GPIO Edge Detect Status registers */

        s->status[bank] &= ~value;

        pxa2xx_gpio_irq_update(s);

        break;

    default:

        cpu_abort(cpu_single_env,

                "%s: Bad offset " REG_FMT "\n", __FUNCTION__, offset);

    }

}

static CPUReadMemoryFunc *pxa2xx_gpio_readfn[] = {

    pxa2xx_gpio_read,

    pxa2xx_gpio_read,

    pxa2xx_gpio_read

};

static CPUWriteMemoryFunc *pxa2xx_gpio_writefn[] = {

    pxa2xx_gpio_write,

    pxa2xx_gpio_write,

    pxa2xx_gpio_write

};

static void pxa2xx_gpio_save(QEMUFile *f, void *opaque)

{

    struct pxa2xx_gpio_info_s *s = (struct pxa2xx_gpio_info_s *) opaque;

    int i;

    qemu_put_be32(f, s->lines);

    for (i = 0; i < PXA2XX_GPIO_BANKS; i ++) {

        qemu_put_be32s(f, &s->ilevel[i]);

        qemu_put_be32s(f, &s->olevel[i]);

        qemu_put_be32s(f, &s->dir[i]);

        qemu_put_be32s(f, &s->rising[i]);

        qemu_put_be32s(f, &s->falling[i]);

        qemu_put_be32s(f, &s->status[i]);

        qemu_put_be32s(f, &s->gafr[i * 2 + 0]);

        qemu_put_be32s(f, &s->gafr[i * 2 + 1]);

        qemu_put_be32s(f, &s->prev_level[i]);

    }

}

static int pxa2xx_gpio_load(QEMUFile *f, void *opaque, int version_id)

{

    struct pxa2xx_gpio_info_s *s = (struct pxa2xx_gpio_info_s *) opaque;

    int i;

    if (qemu_get_be32(f) != s->lines)

        return -EINVAL;

    for (i = 0; i < PXA2XX_GPIO_BANKS; i ++) {

        qemu_get_be32s(f, &s->ilevel[i]);

        qemu_get_be32s(f, &s->olevel[i]);

        qemu_get_be32s(f, &s->dir[i]);

        qemu_get_be32s(f, &s->rising[i]);

        qemu_get_be32s(f, &s->falling[i]);

        qemu_get_be32s(f, &s->status[i]);

        qemu_get_be32s(f, &s->gafr[i * 2 + 0]);

        qemu_get_be32s(f, &s->gafr[i * 2 + 1]);

        qemu_get_be32s(f, &s->prev_level[i]);

    }

    return 0;

}

struct pxa2xx_gpio_info_s *pxa2xx_gpio_init(target_phys_addr_t base,

                CPUState *env, qemu_irq *pic, int lines)

{

    int iomemtype;

    struct pxa2xx_gpio_info_s *s;

    s = (struct pxa2xx_gpio_info_s *)

            qemu_mallocz(sizeof(struct pxa2xx_gpio_info_s));

    memset(s, 0, sizeof(struct pxa2xx_gpio_info_s));

    s->pic = pic;

    s->lines = lines;

    s->cpu_env = env;

    s->in = qemu_allocate_irqs(pxa2xx_gpio_set, s, lines);

    iomemtype = cpu_register_io_memory(0, pxa2xx_gpio_readfn,

                    pxa2xx_gpio_writefn, s);

    cpu_register_physical_memory(base, 0x00001000, iomemtype);

    register_savevm("pxa2xx_gpio", 0, 0,

                    pxa2xx_gpio_save, pxa2xx_gpio_load, s);

    return s;

}

qemu_irq *pxa2xx_gpio_in_get(struct pxa2xx_gpio_info_s *s)

{

    return s->in;

}

void pxa2xx_gpio_out_set(struct pxa2xx_gpio_info_s *s,

                int line, qemu_irq handler)

{

    if (line >= s->lines) {

        printf("%s: No GPIO pin %i\n", __FUNCTION__, line);

        return;

    }

    s->handler[line] = handler;

}

/*

 * Registers a callback to notify on GPLR reads.  This normally

 * shouldn't be needed but it is used for the hack on Spitz machines.

 */

void pxa2xx_gpio_read_notifier(struct pxa2xx_gpio_info_s *s, qemu_irq handler)

{

    s->read_notify = handler;

}