Re: [Qemu-devel] [PATCH v3 06/14] ARM: exynos4210: PWM support.

[Peter Maydell]

On 12 December 2011 06:43, Evgeny Voevodin <address@hidden> wrote:
>
> Signed-off-by: Evgeny Voevodin <address@hidden>
> ---
>  Makefile.target     |    2 +-
>  hw/exynos4210.c     |   12 ++
>  hw/exynos4210_pwm.c |  433 
> +++++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 446 insertions(+), 1 deletions(-)
>  create mode 100644 hw/exynos4210_pwm.c
>
> diff --git a/Makefile.target b/Makefile.target
> index 779c9d4..709e9e2 100644
> --- a/Makefile.target
> +++ b/Makefile.target
> @@ -345,7 +345,7 @@ obj-arm-y += arm_boot.o pl011.o pl031.o pl050.o pl080.o 
> pl110.o pl181.o pl190.o
>  obj-arm-y += versatile_pci.o
>  obj-arm-y += realview_gic.o realview.o arm_sysctl.o arm11mpcore.o a9mpcore.o
>  obj-arm-y += exynos4210.o exynos4210_cmu.o exynos4210_uart.o 
> exynos4210_gic.o \
> -             exynos4210_combiner.o
> +             exynos4210_combiner.o exynos4210_pwm.o
>  obj-arm-y += armv7m.o armv7m_nvic.o stellaris.o pl022.o stellaris_enet.o
>  obj-arm-y += pl061.o
>  obj-arm-y += arm-semi.o
> diff --git a/hw/exynos4210.c b/hw/exynos4210.c
> index 45d427e..7a7760d 100644
> --- a/hw/exynos4210.c
> +++ b/hw/exynos4210.c
> @@ -65,6 +65,9 @@
>  /* SFR Base Address for CMUs */
>  #define EXYNOS4210_CMU_BASE_ADDR            0x10030000
>
> +/* PWM */
> +#define EXYNOS4210_PWM_BASE_ADDR            0x139D0000
> +
>  /* UART's definitions */
>  #define EXYNOS4210_UART_BASE_ADDR           0x13800000
>  #define EXYNOS4210_UART_SHIFT               0x00010000
> @@ -364,6 +367,15 @@ static void exynos4210_init(ram_addr_t ram_size,
>     /* CMU */
>     sysbus_create_simple("exynos4210.cmu", EXYNOS4210_CMU_BASE_ADDR, NULL);
>
> +    /* PWM */
> +    sysbus_create_varargs("exynos4210.pwm", EXYNOS4210_PWM_BASE_ADDR,
> +            irq_table[exynos4210_get_irq(22, 0)],
> +            irq_table[exynos4210_get_irq(22, 1)],
> +            irq_table[exynos4210_get_irq(22, 2)],
> +            irq_table[exynos4210_get_irq(22, 3)],
> +            irq_table[exynos4210_get_irq(22, 4)],
> +            NULL);
> +
>     /*** UARTs ***/
>     for (n = 0; n < EXYNOS4210_UARTS_NUMBER; n++) {
>
> diff --git a/hw/exynos4210_pwm.c b/hw/exynos4210_pwm.c
> new file mode 100644
> index 0000000..1e80f10
> --- /dev/null
> +++ b/hw/exynos4210_pwm.c
> @@ -0,0 +1,433 @@
> +/*
> + * Samsung exynos4210 Pulse Width Modulation Timer
> + *
> + * Copyright (c) 2000 - 2011 Samsung Electronics Co., Ltd.
> + * All rights reserved.
> + *
> + * Evgeny Voevodin <address@hidden>
> + *
> + * 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, write to the Free Software Foundation, Inc., 51
> + * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> + */
> +
> +#include "sysbus.h"
> +#include "qemu-timer.h"
> +#include "qemu-common.h"
> +#include "hw.h"
> +
> +#include "exynos4210.h"
> +
> +//#define DEBUG_PWM
> +
> +#ifdef DEBUG_PWM
> +#define DPRINTF(fmt, ...) \
> +        do { fprintf(stdout, "PWM: [%24s:%5d] " fmt, __func__, __LINE__, \
> +                ## __VA_ARGS__); } while (0)
> +#else
> +#define DPRINTF(fmt, ...) do {} while (0)
> +#endif
> +
> +#define     EXYNOS4210_PWM_TIMERS_NUM      5
> +#define     EXYNOS4210_PWM_REG_MEM_SIZE    0x50
> +
> +#define     TCFG0        0x0000
> +#define     TCFG1        0x0004
> +#define     TCON         0x0008
> +#define     TCNTB0       0x000C
> +#define     TCMPB0       0x0010
> +#define     TCNTO0       0x0014
> +#define     TCNTB1       0x0018
> +#define     TCMPB1       0x001C
> +#define     TCNTO1       0x0020
> +#define     TCNTB2       0x0024
> +#define     TCMPB2       0x0028
> +#define     TCNTO2       0x002C
> +#define     TCNTB3       0x0030
> +#define     TCMPB3       0x0034
> +#define     TCNTO3       0x0038
> +#define     TCNTB4       0x003C
> +#define     TCNTO4       0x0040
> +#define     TINT_CSTAT   0x0044
> +
> +#define     TCNTB(x)    (0xC*x)
> +#define     TCMPB(x)    (0xC*x+1)
> +#define     TCNTO(x)    (0xC*x+2)
> +
> +#define     GET_PRESCALER(reg, x)  ((reg&(0xFF<<(8*x)))>>8*x)
> +#define     GET_DIVIDER(reg, x)    (1<<((0xF<<(4*x))>>(4*x)))
> +
> +/*
> + * Attention! Timer4 doesn't have OUTPUT_INVERTER,
> + * so Auto Reload bit is not accessible by macros!
> + */
> +#define     TCON_TIMER_BASE(x)          ((x ? 1 : 0)*4 + 4*x)
> +#define     TCON_TIMER_START(x)         (1<<(TCON_TIMER_BASE(x) + 0))
> +#define     TCON_TIMER_MANUAL_UPD(x)    (1<<(TCON_TIMER_BASE(x) + 1))
> +#define     TCON_TIMER_OUTPUT_INV(x)    (1<<(TCON_TIMER_BASE(x) + 2))
> +#define     TCON_TIMER_AUTO_RELOAD(x)   (1<<(TCON_TIMER_BASE(x) + 3))
> +#define     TCON_TIMER4_AUTO_RELOAD     (1<<22)
> +
> +#define     TINT_CSTAT_STATUS(x)        (1<<(5+x))
> +#define     TINT_CSTAT_ENABLE(x)        (1<<x)
> +
> +/* timer struct */
> +typedef struct {
> +    uint32_t    id;             /* timer id */
> +    qemu_irq    irq;            /* local timer irq */
> +    uint32_t    freq;           /* timer frequency */
> +
> +    /* use ptimer.c to represent count down timer */
> +    ptimer_state *ptimer;       /* timer  */
> +
> +    /* registers */
> +    uint32_t    reg_tcntb;       /* counter register buffer */
> +    uint32_t    reg_tcmpb;       /* compare register buffer */
> +
> +} Exynos4210_pwm;
> +
> +
> +typedef struct Exynos4210PWMState {
> +    SysBusDevice busdev;
> +    MemoryRegion iomem;
> +
> +    uint32_t    reg_tcfg[2];
> +    uint32_t    reg_tcon;
> +    uint32_t    reg_tint_cstat;
> +
> +    Exynos4210CmuClock clk;         /* clock source for timer */
> +    Exynos4210_pwm timer[EXYNOS4210_PWM_TIMERS_NUM];
> +
> +} Exynos4210PWMState;
> +
> +/*** VMState ***/
> +static const VMStateDescription VMState_Exynos4210_pwm = {
> +        .name = "exynos4210.pwm.pwm",
> +        .version_id = 1,
> +        .minimum_version_id = 1,
> +        .minimum_version_id_old = 1,
> +        .fields = (VMStateField[]) {
> +            VMSTATE_UINT32(id, Exynos4210_pwm),
> +            VMSTATE_UINT32(freq, Exynos4210_pwm),
> +            VMSTATE_UINT32(reg_tcntb, Exynos4210_pwm),
> +            VMSTATE_UINT32(reg_tcmpb, Exynos4210_pwm),
> +            VMSTATE_END_OF_LIST()
> +        }
> +};
> +
> +static const VMStateDescription VMState_Exynos4210PWMState = {
> +        .name = "exynos4210.pwm",
> +        .version_id = 1,
> +        .minimum_version_id = 1,
> +        .minimum_version_id_old = 1,
> +        .fields = (VMStateField[]) {
> +            VMSTATE_UINT32_ARRAY(reg_tcfg, Exynos4210PWMState, 2),
> +            VMSTATE_UINT32(reg_tcon, Exynos4210PWMState),
> +            VMSTATE_UINT32(reg_tint_cstat, Exynos4210PWMState),
> +            VMSTATE_STRUCT_ARRAY(timer, Exynos4210PWMState,
> +                    EXYNOS4210_PWM_TIMERS_NUM, 0,
> +            VMState_Exynos4210_pwm, Exynos4210_pwm),
> +            VMSTATE_END_OF_LIST()
> +        }
> +};
> +
> +/*
> + * PWM update frequency
> + */
> +static void exynos4210_pwm_update_freq(Exynos4210PWMState *s, uint32_t id)
> +{
> +    uint32_t freq;
> +    freq = s->timer[id].freq;
> +    if (id > 1) {
> +        s->timer[id].freq = exynos4210_cmu_get_rate(s->clk) /
> +        ((GET_PRESCALER(s->reg_tcfg[0], 1) + 1) *
> +                (1<<GET_DIVIDER(s->reg_tcfg[1], id)));
> +    } else {
> +        s->timer[id].freq = exynos4210_cmu_get_rate(s->clk) /
> +        ((GET_PRESCALER(s->reg_tcfg[0], 0) + 1) *
> +                (1<<GET_DIVIDER(s->preg_tcfg[1], id)));
> +    }
> +
> +    if (freq != s->timer[id].freq) {
> +        ptimer_set_freq(s->timer[id].ptimer, s->timer[id].freq);
> +        DPRINTF("freq=%dHz\n", s->timer[id].freq);
> +    }
> +}
> +
> +/*
> + * Counter tick handler
> + */
> +static void exynos4210_pwm_tick(void *opaque, uint32_t id)
> +{
> +    Exynos4210PWMState *s = (Exynos4210PWMState *)opaque;
> +    bool cmp;
> +
> +    DPRINTF("timer %d tick\n", id);
> +
> +    /* set irq status */
> +    s->reg_tint_cstat |= TINT_CSTAT_STATUS(id);
> +
> +    /* raise IRQ */
> +    if (s->reg_tint_cstat & TINT_CSTAT_ENABLE(id)) {
> +        DPRINTF("timer %d IRQ\n", id);
> +        qemu_irq_raise(s->timer[id].irq);
> +    }
> +
> +    /* reload timer */
> +    if (id != 4) {
> +        cmp = s->reg_tcon & TCON_TIMER_AUTO_RELOAD(id);
> +    } else {
> +        cmp = s->reg_tcon & TCON_TIMER4_AUTO_RELOAD;
> +    }
> +
> +    if (cmp) {
> +        DPRINTF("auto reload timer %d count to %x\n", id,
> +                s->timer[id].reg_tcntb);
> +        ptimer_set_count(s->timer[id].ptimer, s->timer[id].reg_tcntb);
> +        ptimer_run(s->timer[id].ptimer, 1);
> +    } else {
> +        /* stop timer, set status to STOP, see Basic Timer Operation */
> +        s->reg_tcon = ~TCON_TIMER_START(id);
> +        ptimer_stop(s->timer[id].ptimer);
> +    }
> +}
> +
> +static void exynos4210_pwm_tick0(void *opaque)
> +{
> +    exynos4210_pwm_tick(opaque, 0);
> +}
> +static void exynos4210_pwm_tick1(void *opaque)
> +{
> +    exynos4210_pwm_tick(opaque, 1);
> +}
> +static void exynos4210_pwm_tick2(void *opaque)
> +{
> +    exynos4210_pwm_tick(opaque, 2);
> +}
> +static void exynos4210_pwm_tick3(void *opaque)
> +{
> +    exynos4210_pwm_tick(opaque, 3);
> +}
> +static void exynos4210_pwm_tick4(void *opaque)
> +{
> +    exynos4210_pwm_tick(opaque, 4);
> +}

If you make the Exynos4210_pwm struct include a pointer back to the
Exynos4210PWMState struct, then you can make exynos4210_pwm_tick
take a pointer to the Exynos4210_pwm struct, and then you can
drop these wrapper functions and just say
   bh[i] = qemu_bh_new(exynos4210_pwm_tick, &s->timer[i]);

> +
> +/*
> + * PWM Read
> + */
> +static uint64_t exynos4210_pwm_read(void *opaque, target_phys_addr_t offset,
> +        unsigned size)
> +{
> +    Exynos4210PWMState *s = (Exynos4210PWMState *)opaque;
> +    uint32_t value = 0;
> +    int index;
> +
> +    switch (offset) {
> +    case TCFG0: case TCFG1:
> +        index = (offset - TCFG0)>>2;
> +        value = s->reg_tcfg[index];
> +        break;
> +
> +    case TCON:
> +        value = s->reg_tcon;
> +        break;
> +
> +    case TCNTB0: case TCNTB1:
> +    case TCNTB2: case TCNTB3: case TCNTB4:
> +        index = (offset - TCNTB0)/0xC;
> +        value = s->timer[index].reg_tcntb;
> +        break;
> +
> +    case TCMPB0: case TCMPB1:
> +    case TCMPB2: case TCMPB3:
> +        index = (offset - TCMPB0)/0xC;
> +        value = s->timer[index].reg_tcmpb;
> +        break;
> +
> +    case TCNTO0: case TCNTO1:
> +    case TCNTO2: case TCNTO3: case TCNTO4:
> +        index = (offset == TCNTO4) ? 4 : (offset - TCNTO0)/0xC;
> +        value = ptimer_get_count(s->timer[index].ptimer);
> +        break;
> +
> +    case TINT_CSTAT:
> +        value = s->reg_tint_cstat;
> +        break;
> +
> +    default:
> +        fprintf(stderr,
> +                "[exynos4210.pwm: bad read offset " TARGET_FMT_plx "]\n",
> +                offset);
> +        break;
> +    }
> +    return value;
> +}
> +
> +/*
> + * PWM Write
> + */
> +static void exynos4210_pwm_write(void *opaque, target_phys_addr_t offset,
> +        uint64_t value, unsigned size)
> +{
> +    Exynos4210PWMState *s = (Exynos4210PWMState *)opaque;
> +    int index;
> +    uint32_t new_val;
> +    int i;
> +
> +    switch (offset) {
> +    case TCFG0: case TCFG1:
> +        index = (offset - TCFG0)>>2;
> +        s->reg_tcfg[index] = value;
> +
> +        /* update timers frequencies */
> +        for (i = 0; i < EXYNOS4210_PWM_TIMERS_NUM; i++) {
> +            exynos4210_pwm_update_freq(s, s->timer[i].id);
> +        }
> +        break;
> +
> +    case TCON:
> +        for (i = 0; i < EXYNOS4210_PWM_TIMERS_NUM; i++) {
> +            if ((value & TCON_TIMER_MANUAL_UPD(i)) >
> +            (s->reg_tcon & TCON_TIMER_MANUAL_UPD(i))) {
> +                /*
> +                 * TCNTB and TCMPB are loaded into TCNT and TCMP.
> +                 * Update timers.
> +                 */
> +
> +                /* this will start timer to run, this ok, because
> +                 * during processing start bit timer will be stopped
> +                 * if needed */
> +                ptimer_set_count(s->timer[i].ptimer, s->timer[i].reg_tcntb);
> +                DPRINTF("set timer %d count to %x\n", i,
> +                        s->timer[i].reg_tcntb);
> +            }
> +
> +            if ((value & TCON_TIMER_START(i)) >
> +            (s->reg_tcon & TCON_TIMER_START(i))) {
> +                /* changed to start */
> +                ptimer_run(s->timer[i].ptimer, 1);
> +                DPRINTF("run timer %d\n", i);
> +            }
> +
> +            if ((value & TCON_TIMER_START(i)) <
> +                    (s->reg_tcon & TCON_TIMER_START(i))) {
> +                /* changed to stop */
> +                ptimer_stop(s->timer[i].ptimer);
> +                DPRINTF("stop timer %d\n", i);
> +            }
> +        }
> +        s->reg_tcon = value;
> +        break;
> +
> +    case TCNTB0: case TCNTB1:
> +    case TCNTB2: case TCNTB3: case TCNTB4:
> +        index = (offset - TCNTB0)/0xC;
> +        s->timer[index].reg_tcntb = value;
> +        break;
> +
> +    case TCMPB0: case TCMPB1:
> +    case TCMPB2: case TCMPB3:
> +        index = (offset - TCMPB0)/0xC;
> +        s->timer[index].reg_tcmpb = value;
> +        break;
> +
> +    case TINT_CSTAT:
> +        new_val = (s->reg_tint_cstat&0x3E0) + (0x1F & value);
> +        new_val &= ~(0x3E0 & value);
> +
> +        for (i = 0; i < EXYNOS4210_PWM_TIMERS_NUM; i++) {
> +            if ((new_val & TINT_CSTAT_STATUS(i)) <
> +                    (s->reg_tint_cstat & TINT_CSTAT_STATUS(i))) {
> +                qemu_irq_lower(s->timer[i].irq);
> +            }
> +        }
> +
> +        s->reg_tint_cstat = new_val;
> +        break;
> +
> +    default:
> +        fprintf(stderr,
> +                "[exynos4210.pwm: bad write offset " TARGET_FMT_plx "]\n",
> +                offset);
> +        break;
> +
> +    }
> +}
> +
> +/*
> + * Set default values to timer fields and registers
> + */
> +static void exynos4210_pwm_reset(Exynos4210PWMState *s)
> +{
> +    int i;
> +    s->reg_tcfg[0] = 0x0101;
> +    s->reg_tcfg[1] = 0x0;
> +    s->reg_tcon = 0;
> +    s->reg_tint_cstat = 0;
> +    for (i = 0; i < EXYNOS4210_PWM_TIMERS_NUM; i++) {
> +        s->timer[i].reg_tcmpb = 0;
> +        s->timer[i].reg_tcntb = 0;
> +
> +        exynos4210_pwm_update_freq(s, s->timer[i].id);
> +        ptimer_stop(s->timer[i].ptimer);
> +    }
> +}
> +
> +static const MemoryRegionOps exynos4210_pwm_ops = {
> +        .read = exynos4210_pwm_read,
> +        .write = exynos4210_pwm_write,
> +        .endianness = DEVICE_NATIVE_ENDIAN,
> +};
> +
> +/*
> + * PWM timer initialization
> + */
> +static int exynos4210_pwm_init(SysBusDevice *dev)
> +{
> +    Exynos4210PWMState *s = FROM_SYSBUS(Exynos4210PWMState, dev);
> +    int i;
> +    QEMUBH * bh[EXYNOS4210_PWM_TIMERS_NUM];
> +
> +    s->clk = ACLK_100;
> +
> +    bh[0] = qemu_bh_new(exynos4210_pwm_tick0, s);
> +    bh[1] = qemu_bh_new(exynos4210_pwm_tick1, s);
> +    bh[2] = qemu_bh_new(exynos4210_pwm_tick2, s);
> +    bh[3] = qemu_bh_new(exynos4210_pwm_tick3, s);
> +    bh[4] = qemu_bh_new(exynos4210_pwm_tick4, s);
> +
> +    for (i = 0; i < EXYNOS4210_PWM_TIMERS_NUM; i++) {
> +        sysbus_init_irq(dev, &s->timer[i].irq);
> +        s->timer[i].ptimer = ptimer_init(bh[i]);
> +        s->timer[i].id = i;
> +    }
> +
> +    memory_region_init_io(&s->iomem, &exynos4210_pwm_ops, s, 
> "exynos4210-pwm",
> +            EXYNOS4210_PWM_REG_MEM_SIZE);
> +    sysbus_init_mmio(dev, &s->iomem);
> +
> +    exynos4210_pwm_reset(s);
> +
> +    qemu_register_reset((QEMUResetHandler *)exynos4210_pwm_reset, s);
> +    vmstate_register(NULL, -1, &VMState_Exynos4210PWMState, s);

Same remarks about reset, vmstate as in other patch review mail.

> +    return 0;
> +}
> +
> +static void exynos4210_pwm_register_devices(void)
> +{
> +    sysbus_register_dev("exynos4210.pwm", sizeof(Exynos4210PWMState),
> +            exynos4210_pwm_init);
> +}
> +
> +device_init(exynos4210_pwm_register_devices)
> --
> 1.7.4.1
>
>