hw/arm/digic: add timer support

Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 1387188908-754-4-git-send-email-antonynpavlov@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 163 insertions, 0 deletions

diff --git a/hw/timer/digic-timer.c b/hw/timer/digic-timer.c
new file mode 100644
index 0000000000..1fde22c67f
--- /dev/null
+++ b/hw/timer/digic-timer.c
@@ -0,0 +1,163 @@
+/*
+ * QEMU model of the Canon DIGIC timer block.
+ *
+ * Copyright (C) 2013 Antony Pavlov <antonynpavlov@gmail.com>
+ *
+ * This model is based on reverse engineering efforts
+ * made by CHDK (http://chdk.wikia.com) and
+ * Magic Lantern (http://www.magiclantern.fm) projects
+ * contributors.
+ *
+ * See "Timer/Clock Module" docs here:
+ *   http://magiclantern.wikia.com/wiki/Register_Map
+ *
+ * The QEMU model of the OSTimer in PKUnity SoC by Guan Xuetao
+ * is used as a template.
+ *
+ * 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.
+ *
+ */
+
+#include "hw/sysbus.h"
+#include "hw/ptimer.h"
+#include "qemu/main-loop.h"
+
+#include "hw/timer/digic-timer.h"
+
+static const VMStateDescription vmstate_digic_timer = {
+    .name = "digic.timer",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .minimum_version_id_old = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_PTIMER(ptimer, DigicTimerState),
+        VMSTATE_UINT32(control, DigicTimerState),
+        VMSTATE_UINT32(relvalue, DigicTimerState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void digic_timer_reset(DeviceState *dev)
+{
+    DigicTimerState *s = DIGIC_TIMER(dev);
+
+    ptimer_stop(s->ptimer);
+    s->control = 0;
+    s->relvalue = 0;
+}
+
+static uint64_t digic_timer_read(void *opaque, hwaddr offset, unsigned size)
+{
+    DigicTimerState *s = opaque;
+    uint64_t ret = 0;
+
+    switch (offset) {
+    case DIGIC_TIMER_CONTROL:
+        ret = s->control;
+        break;
+    case DIGIC_TIMER_RELVALUE:
+        ret = s->relvalue;
+        break;
+    case DIGIC_TIMER_VALUE:
+        ret = ptimer_get_count(s->ptimer) & 0xffff;
+        break;
+    default:
+        qemu_log_mask(LOG_UNIMP,
+                      "digic-timer: read access to unknown register 0x"
+                      TARGET_FMT_plx, offset);
+    }
+
+    return ret;
+}
+
+static void digic_timer_write(void *opaque, hwaddr offset,
+                              uint64_t value, unsigned size)
+{
+    DigicTimerState *s = opaque;
+
+    switch (offset) {
+    case DIGIC_TIMER_CONTROL:
+        if (value & DIGIC_TIMER_CONTROL_RST) {
+            digic_timer_reset((DeviceState *)s);
+            break;
+        }
+
+        if (value & DIGIC_TIMER_CONTROL_EN) {
+            ptimer_run(s->ptimer, 0);
+        }
+
+        s->control = (uint32_t)value;
+        break;
+
+    case DIGIC_TIMER_RELVALUE:
+        s->relvalue = extract32(value, 0, 16);
+        ptimer_set_limit(s->ptimer, s->relvalue, 1);
+        break;
+
+    case DIGIC_TIMER_VALUE:
+        break;
+
+    default:
+        qemu_log_mask(LOG_UNIMP,
+                      "digic-timer: read access to unknown register 0x"
+                      TARGET_FMT_plx, offset);
+    }
+}
+
+static const MemoryRegionOps digic_timer_ops = {
+    .read = digic_timer_read,
+    .write = digic_timer_write,
+    .impl = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    },
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static void digic_timer_init(Object *obj)
+{
+    DigicTimerState *s = DIGIC_TIMER(obj);
+
+    s->ptimer = ptimer_init(NULL);
+
+    /*
+     * FIXME: there is no documentation on Digic timer
+     * frequency setup so let it always run at 1 MHz
+     */
+    ptimer_set_freq(s->ptimer, 1 * 1000 * 1000);
+
+    memory_region_init_io(&s->iomem, OBJECT(s), &digic_timer_ops, s,
+                          TYPE_DIGIC_TIMER, 0x100);
+    sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->iomem);
+}
+
+static void digic_timer_class_init(ObjectClass *klass, void *class_data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->reset = digic_timer_reset;
+    dc->vmsd = &vmstate_digic_timer;
+}
+
+static const TypeInfo digic_timer_info = {
+    .name = TYPE_DIGIC_TIMER,
+    .parent = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(DigicTimerState),
+    .instance_init = digic_timer_init,
+    .class_init = digic_timer_class_init,
+};
+
+static void digic_timer_register_type(void)
+{
+    type_register_static(&digic_timer_info);
+}
+
+type_init(digic_timer_register_type)