Archipelago » qemu

/*

 * SuperH interrupt controller module

 *

 * Copyright (c) 2007 Magnus Damm

 * Based on sh_timer.c and arm_timer.c by Paul Brook

 * Copyright (c) 2005-2006 CodeSourcery.

 *

 * This code is licenced under the GPL.

 */

#include <assert.h>

#include "sh_intc.h"

#include "vl.h"

//#define DEBUG_INTC

#define INTC_A7(x) ((x) & 0x1fffffff)

#define INTC_ARRAY(x) (sizeof(x) / sizeof(x[0]))

#define INTC_MODE_NONE       0

#define INTC_MODE_DUAL_SET   1

#define INTC_MODE_DUAL_CLR   2

#define INTC_MODE_ENABLE_REG 3

#define INTC_MODE_MASK_REG   4

#define INTC_MODE_IS_PRIO    8

static unsigned int sh_intc_mode(unsigned long address,

                                 unsigned long set_reg, unsigned long clr_reg)

{

    if ((address != INTC_A7(set_reg)) &&

        (address != INTC_A7(clr_reg)))

        return INTC_MODE_NONE;

    if (set_reg && clr_reg) {

        if (address == INTC_A7(set_reg))

            return INTC_MODE_DUAL_SET;

        else

            return INTC_MODE_DUAL_CLR;

    }

    if (set_reg)

        return INTC_MODE_ENABLE_REG;

    else

        return INTC_MODE_MASK_REG;

}

static void sh_intc_locate(struct intc_desc *desc,

                           unsigned long address,

                           unsigned long **datap,

                           intc_enum **enums,

                           unsigned int *first,

                           unsigned int *width,

                           unsigned int *modep)

{

    unsigned int i, mode;

    /* this is slow but works for now */

    if (desc->mask_regs) {

        for (i = 0; i < desc->nr_mask_regs; i++) {

            struct intc_mask_reg *mr = desc->mask_regs + i;

            mode = sh_intc_mode(address, mr->set_reg, mr->clr_reg);

            if (mode == INTC_MODE_NONE)

                continue;

            *modep = mode;

            *datap = &mr->value;

            *enums = mr->enum_ids;

            *first = mr->reg_width - 1;

            *width = 1;

            return;

        }

    }

    if (desc->prio_regs) {

        for (i = 0; i < desc->nr_prio_regs; i++) {

            struct intc_prio_reg *pr = desc->prio_regs + i;

            mode = sh_intc_mode(address, pr->set_reg, pr->clr_reg);

            if (mode == INTC_MODE_NONE)

                continue;

            *modep = mode | INTC_MODE_IS_PRIO;

            *datap = &pr->value;

            *enums = pr->enum_ids;

            *first = (pr->reg_width / pr->field_width) - 1;

            *width = pr->field_width;

            return;

        }

    }

    assert(0);

}

static void sh_intc_toggle(struct intc_desc *desc, intc_enum id,

                           int enable, int is_group)

{

    struct intc_source *source = desc->sources + id;

    int old = source->enable_count;

    if (!id)

        return;

    if (!source->next_enum_id && (!source->enable_max || !source->vect)) {

#ifdef DEBUG_INTC

        printf("sh_intc: reserved interrupt source %d modified\n", id);

#endif

        return;

    }

    if (source->vect) {

        if (enable)

            source->enable_count++;

        else 

            source->enable_count--;

        if (source->enable_count == source->enable_max) {

#ifdef DEBUG_INTC

            printf("sh_intc: enabling interrupt source %d -> 0x%04x\n",

                   id, source->vect);

#endif

        }

        if (old == source->enable_max) {

#ifdef DEBUG_INTC

            printf("sh_intc: disabling interrupt source %d -> 0x%04x\n",

                   id, source->vect);

#endif

        }

    }

#ifdef DEBUG_INTC

    else {

        printf("setting interrupt group %d to %d\n", id, !!enable);

    }

#endif

    if ((is_group || !source->vect) && source->next_enum_id) {

        sh_intc_toggle(desc, source->next_enum_id, enable, 1);

    }

#ifdef DEBUG_INTC

    if (!source->vect) {

        printf("setting interrupt group %d to %d - done\n", id, !!enable);

    }

#endif

}

static uint32_t sh_intc_read(void *opaque, target_phys_addr_t offset)

{

    struct intc_desc *desc = opaque;

    intc_enum *enum_ids = NULL;

    unsigned int first = 0;

    unsigned int width = 0;

    unsigned int mode = 0;

    unsigned long *valuep;

#ifdef DEBUG_INTC

    printf("sh_intc_read 0x%lx\n", (unsigned long) offset);

#endif

    sh_intc_locate(desc, (unsigned long)offset, &valuep, 

                   &enum_ids, &first, &width, &mode);

    return *valuep;

}

static void sh_intc_write(void *opaque, target_phys_addr_t offset,

                          uint32_t value)

{

    struct intc_desc *desc = opaque;

    intc_enum *enum_ids = NULL;

    unsigned int first = 0;

    unsigned int width = 0;

    unsigned int mode = 0;

    unsigned int k;

    unsigned long *valuep;

    unsigned long mask;

#ifdef DEBUG_INTC

    printf("sh_intc_write 0x%lx 0x%08x\n", (unsigned long) offset, value);

#endif

    sh_intc_locate(desc, (unsigned long)offset, &valuep, 

                   &enum_ids, &first, &width, &mode);

    switch (mode) {

    case INTC_MODE_ENABLE_REG | INTC_MODE_IS_PRIO: break;

    case INTC_MODE_DUAL_SET: value |= *valuep; break;

    case INTC_MODE_DUAL_CLR: value = *valuep & ~value; break;

    default: assert(0);

    }

    for (k = 0; k <= first; k++) {

        mask = ((1 << width) - 1) << ((first - k) * width);

        if ((*valuep & mask) == (value & mask))

            continue;

#if 0

        printf("k = %d, first = %d, enum = %d, mask = 0x%08x\n", 

               k, first, enum_ids[k], (unsigned int)mask);

#endif

        sh_intc_toggle(desc, enum_ids[k], value & mask, 0);

    }

    *valuep = value;

#ifdef DEBUG_INTC

    printf("sh_intc_write 0x%lx -> 0x%08x\n", (unsigned long) offset, value);

#endif

}

static CPUReadMemoryFunc *sh_intc_readfn[] = {

    sh_intc_read,

    sh_intc_read,

    sh_intc_read

};

static CPUWriteMemoryFunc *sh_intc_writefn[] = {

    sh_intc_write,

    sh_intc_write,

    sh_intc_write

};

struct intc_source *sh_intc_source(struct intc_desc *desc, intc_enum id)

{

    if (id)

        return desc->sources + id;

    return NULL;

}

static void sh_intc_register(struct intc_desc *desc, 

                             unsigned long address)

{

    if (address)

        cpu_register_physical_memory(INTC_A7(address), 4, desc->iomemtype);

}

static void sh_intc_register_source(struct intc_desc *desc,

                                    intc_enum source,

                                    struct intc_group *groups,

                                    int nr_groups)

{

    unsigned int i, k;

    struct intc_source *s;

    if (desc->mask_regs) {

        for (i = 0; i < desc->nr_mask_regs; i++) {

            struct intc_mask_reg *mr = desc->mask_regs + i;

            for (k = 0; k < INTC_ARRAY(mr->enum_ids); k++) {

                if (mr->enum_ids[k] != source)

                    continue;

                s = sh_intc_source(desc, mr->enum_ids[k]);

                if (s)

                    s->enable_max++;

            }

        }

    }

    if (desc->prio_regs) {

        for (i = 0; i < desc->nr_prio_regs; i++) {

            struct intc_prio_reg *pr = desc->prio_regs + i;

            for (k = 0; k < INTC_ARRAY(pr->enum_ids); k++) {

                if (pr->enum_ids[k] != source)

                    continue;

                s = sh_intc_source(desc, pr->enum_ids[k]);

                if (s)

                    s->enable_max++;

            }

        }

    }

    if (groups) {

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

            struct intc_group *gr = groups + i;

            for (k = 0; k < INTC_ARRAY(gr->enum_ids); k++) {

                if (gr->enum_ids[k] != source)

                    continue;

                s = sh_intc_source(desc, gr->enum_ids[k]);

                if (s)

                    s->enable_max++;

            }

        }

    }

}

void sh_intc_register_sources(struct intc_desc *desc,

                              struct intc_vect *vectors,

                              int nr_vectors,

                              struct intc_group *groups,

                              int nr_groups)

{

    unsigned int i, k;

    struct intc_source *s;

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

        struct intc_vect *vect = vectors + i;

        sh_intc_register_source(desc, vect->enum_id, groups, nr_groups);

        s = sh_intc_source(desc, vect->enum_id);

        if (s)

            s->vect = vect->vect;

#ifdef DEBUG_INTC

        printf("sh_intc: registered source %d -> 0x%04x (%d/%d)\n",

               vect->enum_id, s->vect, s->enable_count, s->enable_max);

#endif

    }

    if (groups) {

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

            struct intc_group *gr = groups + i;

            s = sh_intc_source(desc, gr->enum_id);

            s->next_enum_id = gr->enum_ids[0];

            for (k = 1; k < INTC_ARRAY(gr->enum_ids); k++) {

                if (!gr->enum_ids[k])

                    continue;

                s = sh_intc_source(desc, gr->enum_ids[k - 1]);

                s->next_enum_id = gr->enum_ids[k];

            }

#ifdef DEBUG_INTC

            printf("sh_intc: registered group %d (%d/%d)\n",

                   gr->enum_id, s->enable_count, s->enable_max);

#endif

        }

    }

}

int sh_intc_init(struct intc_desc *desc,

                 int nr_sources,

                 struct intc_mask_reg *mask_regs,

                 int nr_mask_regs,

                 struct intc_prio_reg *prio_regs,

                 int nr_prio_regs)

{

    unsigned int i;

    desc->nr_sources = nr_sources;

    desc->mask_regs = mask_regs;

    desc->nr_mask_regs = nr_mask_regs;

    desc->prio_regs = prio_regs;

    desc->nr_prio_regs = nr_prio_regs;

    i = sizeof(struct intc_source) * nr_sources;

    desc->sources = malloc(i);

    if (!desc->sources)

        return -1;

    memset(desc->sources, 0, i);

    desc->iomemtype = cpu_register_io_memory(0, sh_intc_readfn,

                                             sh_intc_writefn, desc);

    if (desc->mask_regs) {

        for (i = 0; i < desc->nr_mask_regs; i++) {

            struct intc_mask_reg *mr = desc->mask_regs + i;

            sh_intc_register(desc, mr->set_reg);

            sh_intc_register(desc, mr->clr_reg);

        }

    }

    if (desc->prio_regs) {

        for (i = 0; i < desc->nr_prio_regs; i++) {

            struct intc_prio_reg *pr = desc->prio_regs + i;

            sh_intc_register(desc, pr->set_reg);

            sh_intc_register(desc, pr->clr_reg);

        }

    }

    return 0;

}