ARM: exynos4210: PWM support.

Signed-off-by: Evgeny Voevodin <e.voevodin@samsung.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 422 insertions, 0 deletions

diff --git a/hw/exynos4210_pwm.c b/hw/exynos4210_pwm.c
new file mode 100644
index 0000000000..6243e59c48
--- /dev/null
+++ b/hw/exynos4210_pwm.c
@@ -0,0 +1,422 @@
+/*
+ * Samsung exynos4210 Pulse Width Modulation Timer
+ *
+ * Copyright (c) 2000 - 2011 Samsung Electronics Co., Ltd.
+ * All rights reserved.
+ *
+ * Evgeny Voevodin <e.voevodin@samsung.com>
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "sysbus.h"
+#include "qemu-timer.h"
+#include "qemu-common.h"
+#include "ptimer.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 << (((reg) & (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 */
+
+    struct Exynos4210PWMState *parent;
+
+} Exynos4210PWM;
+
+
+typedef struct Exynos4210PWMState {
+    SysBusDevice busdev;
+    MemoryRegion iomem;
+
+    uint32_t    reg_tcfg[2];
+    uint32_t    reg_tcon;
+    uint32_t    reg_tint_cstat;
+
+    Exynos4210PWM 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, Exynos4210PWM),
+        VMSTATE_UINT32(freq, Exynos4210PWM),
+        VMSTATE_PTIMER(ptimer, Exynos4210PWM),
+        VMSTATE_UINT32(reg_tcntb, Exynos4210PWM),
+        VMSTATE_UINT32(reg_tcmpb, Exynos4210PWM),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static const VMStateDescription vmstate_exynos4210_pwm_state = {
+    .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, Exynos4210PWM),
+        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 = 24000000 /
+        ((GET_PRESCALER(s->reg_tcfg[0], 1) + 1) *
+                (GET_DIVIDER(s->reg_tcfg[1], id)));
+    } else {
+        s->timer[id].freq = 24000000 /
+        ((GET_PRESCALER(s->reg_tcfg[0], 0) + 1) *
+                (GET_DIVIDER(s->reg_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)
+{
+    Exynos4210PWM *s = (Exynos4210PWM *)opaque;
+    Exynos4210PWMState *p = (Exynos4210PWMState *)s->parent;
+    uint32_t id = s->id;
+    bool cmp;
+
+    DPRINTF("timer %d tick\n", id);
+
+    /* set irq status */
+    p->reg_tint_cstat |= TINT_CSTAT_STATUS(id);
+
+    /* raise IRQ */
+    if (p->reg_tint_cstat & TINT_CSTAT_ENABLE(id)) {
+        DPRINTF("timer %d IRQ\n", id);
+        qemu_irq_raise(p->timer[id].irq);
+    }
+
+    /* reload timer */
+    if (id != 4) {
+        cmp = p->reg_tcon & TCON_TIMER_AUTO_RELOAD(id);
+    } else {
+        cmp = p->reg_tcon & TCON_TIMER4_AUTO_RELOAD;
+    }
+
+    if (cmp) {
+        DPRINTF("auto reload timer %d count to %x\n", id,
+                p->timer[id].reg_tcntb);
+        ptimer_set_count(p->timer[id].ptimer, p->timer[id].reg_tcntb);
+        ptimer_run(p->timer[id].ptimer, 1);
+    } else {
+        /* stop timer, set status to STOP, see Basic Timer Operation */
+        p->reg_tcon = ~TCON_TIMER_START(id);
+        ptimer_stop(p->timer[id].ptimer);
+    }
+}
+
+/*
+ * 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(DeviceState *d)
+{
+    Exynos4210PWMState *s = (Exynos4210PWMState *)d;
+    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;
+
+    for (i = 0; i < EXYNOS4210_PWM_TIMERS_NUM; i++) {
+        bh = qemu_bh_new(exynos4210_pwm_tick, &s->timer[i]);
+        sysbus_init_irq(dev, &s->timer[i].irq);
+        s->timer[i].ptimer = ptimer_init(bh);
+        s->timer[i].id = i;
+        s->timer[i].parent = s;
+    }
+
+    memory_region_init_io(&s->iomem, &exynos4210_pwm_ops, s, "exynos4210-pwm",
+            EXYNOS4210_PWM_REG_MEM_SIZE);
+    sysbus_init_mmio(dev, &s->iomem);
+
+    return 0;
+}
+
+static void exynos4210_pwm_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
+
+    k->init = exynos4210_pwm_init;
+    dc->reset = exynos4210_pwm_reset;
+    dc->vmsd = &vmstate_exynos4210_pwm_state;
+}
+
+static TypeInfo exynos4210_pwm_info = {
+    .name          = "exynos4210.pwm",
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(Exynos4210PWMState),
+    .class_init    = exynos4210_pwm_class_init,
+};
+
+static void exynos4210_pwm_register_types(void)
+{
+    type_register_static(&exynos4210_pwm_info);
+}
+
+type_init(exynos4210_pwm_register_types)