Archipelago » qemu

/*

 * QEMU ETRAX Timers

 *

 * Copyright (c) 2007 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-timer.h"

#define D(x)

#define RW_TMR0_DIV   0x00

#define R_TMR0_DATA   0x04

#define RW_TMR0_CTRL  0x08

#define RW_TMR1_DIV   0x10

#define R_TMR1_DATA   0x14

#define RW_TMR1_CTRL  0x18

#define R_TIME        0x38

#define RW_WD_CTRL    0x40

#define RW_INTR_MASK  0x48

#define RW_ACK_INTR   0x4c

#define R_INTR        0x50

#define R_MASKED_INTR 0x54

struct fs_timer_t {

        CPUState *env;

        qemu_irq *irq;

        target_phys_addr_t base;

        QEMUBH *bh;

        ptimer_state *ptimer;

        unsigned int limit;

        int scale;

        uint32_t mask;

        struct timeval last;

        uint32_t rw_intr_mask;

        uint32_t rw_ack_intr;

        uint32_t r_intr;

};

/* diff two timevals.  Return a single int in us. */

int diff_timeval_us(struct timeval *a, struct timeval *b)

{

        int diff;

        /* assume these values are signed.  */

        diff = (a->tv_sec - b->tv_sec) * 1000 * 1000;

        diff += (a->tv_usec - b->tv_usec);

        return diff;

}

static uint32_t timer_rinvalid (void *opaque, target_phys_addr_t addr)

{

        struct fs_timer_t *t = opaque;

        CPUState *env = t->env;

        cpu_abort(env, "Unsupported short access. reg=%x pc=%x.\n", 

                  addr, env->pc);

        return 0;

}

static uint32_t timer_readl (void *opaque, target_phys_addr_t addr)

{

        struct fs_timer_t *t = opaque;

        D(CPUState *env = t->env);

        uint32_t r = 0;

        /* Make addr relative to this instances base.  */

        addr -= t->base;

        switch (addr) {

        case R_TMR0_DATA:

                break;

        case R_TMR1_DATA:

                D(printf ("R_TMR1_DATA\n"));

                break;

        case R_TIME:

        {

                struct timeval now;

                gettimeofday(&now, NULL);

                if (!(t->last.tv_sec == 0 

                      && t->last.tv_usec == 0)) {

                        r = diff_timeval_us(&now, &t->last);

                        r *= 1000; /* convert to ns.  */

                        r++; /* make sure we increase for each call.  */

                }

                t->last = now;

                break;

        }

        case RW_INTR_MASK:

                r = t->rw_intr_mask;

                break;

        case R_MASKED_INTR:

                r = t->r_intr & t->rw_intr_mask;

                break;

        default:

                D(printf ("%s %x p=%x\n", __func__, addr, env->pc));

                break;

        }

        return r;

}

static void

timer_winvalid (void *opaque, target_phys_addr_t addr, uint32_t value)

{

        struct fs_timer_t *t = opaque;

        CPUState *env = t->env;

        cpu_abort(env, "Unsupported short access. reg=%x pc=%x.\n", 

                  addr, env->pc);

}

static void write_ctrl(struct fs_timer_t *t, uint32_t v)

{

        int op;

        int freq;

        int freq_hz;

        op = v & 3;

        freq = v >> 2;

        freq_hz = 32000000;

        switch (freq)

        {

        case 0:

        case 1:

                D(printf ("extern or disabled timer clock?\n"));

                break;

        case 4: freq_hz =  29493000; break;

        case 5: freq_hz =  32000000; break;

        case 6: freq_hz =  32768000; break;

        case 7: freq_hz = 100000000; break;

        default:

                abort();

                break;

        }

        D(printf ("freq_hz=%d limit=%d\n", freq_hz, t->limit));

        t->scale = 0;

        if (t->limit > 2048)

        {

                t->scale = 2048;

                ptimer_set_period(t->ptimer, freq_hz / t->scale);

        }

        switch (op)

        {

                case 0:

                        D(printf ("limit=%d %d\n", 

                                  t->limit, t->limit/t->scale));

                        ptimer_set_limit(t->ptimer, t->limit / t->scale, 1);

                        break;

                case 1:

                        ptimer_stop(t->ptimer);

                        break;

                case 2:

                        ptimer_run(t->ptimer, 0);

                        break;

                default:

                        abort();

                        break;

        }

}

static void timer_ack_irq(struct fs_timer_t *t)

{

        if (!(t->r_intr & t->mask & t->rw_intr_mask))

                qemu_irq_lower(t->irq[0]);

}

static void

timer_writel (void *opaque, target_phys_addr_t addr, uint32_t value)

{

        struct fs_timer_t *t = opaque;

        CPUState *env = t->env;

        D(printf ("%s %x %x pc=%x\n",

                __func__, addr, value, env->pc));

        /* Make addr relative to this instances base.  */

        addr -= t->base;

        switch (addr)

        {

                case RW_TMR0_DIV:

                        D(printf ("RW_TMR0_DIV=%x\n", value));

                        t->limit = value;

                        break;

                case RW_TMR0_CTRL:

                        D(printf ("RW_TMR0_CTRL=%x\n", value));

                        write_ctrl(t, value);

                        break;

                case RW_TMR1_DIV:

                        D(printf ("RW_TMR1_DIV=%x\n", value));

                        break;

                case RW_TMR1_CTRL:

                        D(printf ("RW_TMR1_CTRL=%x\n", value));

                        break;

                case RW_INTR_MASK:

                        D(printf ("RW_INTR_MASK=%x\n", value));

                        t->rw_intr_mask = value;

                        break;

                case RW_WD_CTRL:

                        D(printf ("RW_WD_CTRL=%x\n", value));

                        break;

                case RW_ACK_INTR:

                        t->r_intr &= ~value;

                        timer_ack_irq(t);

                        break;

                default:

                        printf ("%s %x %x pc=%x\n",

                                __func__, addr, value, env->pc);

                        break;

        }

}

static CPUReadMemoryFunc *timer_read[] = {

    &timer_rinvalid,

    &timer_rinvalid,

    &timer_readl,

};

static CPUWriteMemoryFunc *timer_write[] = {

    &timer_winvalid,

    &timer_winvalid,

    &timer_writel,

};

static void timer_irq(void *opaque)

{

        struct fs_timer_t *t = opaque;

        t->r_intr |= t->mask;

        if (t->mask & t->rw_intr_mask) {

                D(printf("%s raise\n", __func__));

                qemu_irq_raise(t->irq[0]);

        }

}

void etraxfs_timer_init(CPUState *env, qemu_irq *irqs, 

                        target_phys_addr_t base)

{

        static struct fs_timer_t *t;

        int timer_regs;

        t = qemu_mallocz(sizeof *t);

        if (!t)

                return;

        t->bh = qemu_bh_new(timer_irq, t);

        t->ptimer = ptimer_init(t->bh);

        t->irq = irqs + 26;

        t->mask = 1;

        t->env = env;

        t->base = base;

        timer_regs = cpu_register_io_memory(0, timer_read, timer_write, t);

        cpu_register_physical_memory (base, 0x5c, timer_regs);

}