hw/arm_mptimer.c: Turn ARM MPcore private timers into qdev devices

Turn the ARM MPcore private timer/watchdog blocks into separate
qdev devices. This will allow us to share them neatly between
11MPCore and A9MPcore.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 332 insertions, 0 deletions

diff --git a/hw/arm_mptimer.c b/hw/arm_mptimer.c
new file mode 100644
index 0000000000..455a0aa55a
--- /dev/null
+++ b/hw/arm_mptimer.c
@@ -0,0 +1,332 @@
+/*
+ * Private peripheral timer/watchdog blocks for ARM 11MPCore and A9MP
+ *
+ * Copyright (c) 2006-2007 CodeSourcery.
+ * Copyright (c) 2011 Linaro Limited
+ * Written by Paul Brook, Peter Maydell
+ *
+ * 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"
+
+/* This device implements the per-cpu private timer and watchdog block
+ * which is used in both the ARM11MPCore and Cortex-A9MP.
+ */
+
+#define MAX_CPUS 4
+
+/* State of a single timer or watchdog block */
+typedef struct {
+    uint32_t count;
+    uint32_t load;
+    uint32_t control;
+    uint32_t status;
+    int64_t tick;
+    QEMUTimer *timer;
+    qemu_irq irq;
+    MemoryRegion iomem;
+} timerblock;
+
+typedef struct {
+    SysBusDevice busdev;
+    uint32_t num_cpu;
+    timerblock timerblock[MAX_CPUS * 2];
+    MemoryRegion iomem[2];
+} arm_mptimer_state;
+
+static inline int get_current_cpu(arm_mptimer_state *s)
+{
+    if (cpu_single_env->cpu_index >= s->num_cpu) {
+        hw_error("arm_mptimer: num-cpu %d but this cpu is %d!\n",
+                 s->num_cpu, cpu_single_env->cpu_index);
+    }
+    return cpu_single_env->cpu_index;
+}
+
+static inline void timerblock_update_irq(timerblock *tb)
+{
+    qemu_set_irq(tb->irq, tb->status);
+}
+
+/* Return conversion factor from mpcore timer ticks to qemu timer ticks.  */
+static inline uint32_t timerblock_scale(timerblock *tb)
+{
+    return (((tb->control >> 8) & 0xff) + 1) * 10;
+}
+
+static void timerblock_reload(timerblock *tb, int restart)
+{
+    if (tb->count == 0) {
+        return;
+    }
+    if (restart) {
+        tb->tick = qemu_get_clock_ns(vm_clock);
+    }
+    tb->tick += (int64_t)tb->count * timerblock_scale(tb);
+    qemu_mod_timer(tb->timer, tb->tick);
+}
+
+static void timerblock_tick(void *opaque)
+{
+    timerblock *tb = (timerblock *)opaque;
+    tb->status = 1;
+    if (tb->control & 2) {
+        tb->count = tb->load;
+        timerblock_reload(tb, 0);
+    } else {
+        tb->count = 0;
+    }
+    timerblock_update_irq(tb);
+}
+
+static uint64_t timerblock_read(void *opaque, target_phys_addr_t addr,
+                                unsigned size)
+{
+    timerblock *tb = (timerblock *)opaque;
+    int64_t val;
+    addr &= 0x1f;
+    switch (addr) {
+    case 0: /* Load */
+        return tb->load;
+    case 4: /* Counter.  */
+        if (((tb->control & 1) == 0) || (tb->count == 0)) {
+            return 0;
+        }
+        /* Slow and ugly, but hopefully won't happen too often.  */
+        val = tb->tick - qemu_get_clock_ns(vm_clock);
+        val /= timerblock_scale(tb);
+        if (val < 0) {
+            val = 0;
+        }
+        return val;
+    case 8: /* Control.  */
+        return tb->control;
+    case 12: /* Interrupt status.  */
+        return tb->status;
+    default:
+        return 0;
+    }
+}
+
+static void timerblock_write(void *opaque, target_phys_addr_t addr,
+                             uint64_t value, unsigned size)
+{
+    timerblock *tb = (timerblock *)opaque;
+    int64_t old;
+    addr &= 0x1f;
+    switch (addr) {
+    case 0: /* Load */
+        tb->load = value;
+        /* Fall through.  */
+    case 4: /* Counter.  */
+        if ((tb->control & 1) && tb->count) {
+            /* Cancel the previous timer.  */
+            qemu_del_timer(tb->timer);
+        }
+        tb->count = value;
+        if (tb->control & 1) {
+            timerblock_reload(tb, 1);
+        }
+        break;
+    case 8: /* Control.  */
+        old = tb->control;
+        tb->control = value;
+        if (((old & 1) == 0) && (value & 1)) {
+            if (tb->count == 0 && (tb->control & 2)) {
+                tb->count = tb->load;
+            }
+            timerblock_reload(tb, 1);
+        }
+        break;
+    case 12: /* Interrupt status.  */
+        tb->status &= ~value;
+        timerblock_update_irq(tb);
+        break;
+    }
+}
+
+/* Wrapper functions to implement the "read timer/watchdog for
+ * the current CPU" memory regions.
+ */
+static uint64_t arm_thistimer_read(void *opaque, target_phys_addr_t addr,
+                                   unsigned size)
+{
+    arm_mptimer_state *s = (arm_mptimer_state *)opaque;
+    int id = get_current_cpu(s);
+    return timerblock_read(&s->timerblock[id * 2], addr, size);
+}
+
+static void arm_thistimer_write(void *opaque, target_phys_addr_t addr,
+                                uint64_t value, unsigned size)
+{
+    arm_mptimer_state *s = (arm_mptimer_state *)opaque;
+    int id = get_current_cpu(s);
+    timerblock_write(&s->timerblock[id * 2], addr, value, size);
+}
+
+static uint64_t arm_thiswdog_read(void *opaque, target_phys_addr_t addr,
+                                  unsigned size)
+{
+    arm_mptimer_state *s = (arm_mptimer_state *)opaque;
+    int id = get_current_cpu(s);
+    return timerblock_read(&s->timerblock[id * 2 + 1], addr, size);
+}
+
+static void arm_thiswdog_write(void *opaque, target_phys_addr_t addr,
+                               uint64_t value, unsigned size)
+{
+    arm_mptimer_state *s = (arm_mptimer_state *)opaque;
+    int id = get_current_cpu(s);
+    timerblock_write(&s->timerblock[id * 2 + 1], addr, value, size);
+}
+
+static const MemoryRegionOps arm_thistimer_ops = {
+    .read = arm_thistimer_read,
+    .write = arm_thistimer_write,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    },
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static const MemoryRegionOps arm_thiswdog_ops = {
+    .read = arm_thiswdog_read,
+    .write = arm_thiswdog_write,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    },
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static const MemoryRegionOps timerblock_ops = {
+    .read = timerblock_read,
+    .write = timerblock_write,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    },
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static void timerblock_reset(timerblock *tb)
+{
+    tb->count = 0;
+    tb->load = 0;
+    tb->control = 0;
+    tb->status = 0;
+    tb->tick = 0;
+}
+
+static void arm_mptimer_reset(DeviceState *dev)
+{
+    arm_mptimer_state *s =
+        FROM_SYSBUS(arm_mptimer_state, sysbus_from_qdev(dev));
+    int i;
+    /* We reset every timer in the array, not just the ones we're using,
+     * because vmsave will look at every array element.
+     */
+    for (i = 0; i < ARRAY_SIZE(s->timerblock); i++) {
+        timerblock_reset(&s->timerblock[i]);
+    }
+}
+
+static int arm_mptimer_init(SysBusDevice *dev)
+{
+    arm_mptimer_state *s = FROM_SYSBUS(arm_mptimer_state, dev);
+    int i;
+    if (s->num_cpu < 1 || s->num_cpu > MAX_CPUS) {
+        hw_error("%s: num-cpu must be between 1 and %d\n", __func__, MAX_CPUS);
+    }
+    /* We implement one timer and one watchdog block per CPU, and
+     * expose multiple MMIO regions:
+     *  * region 0 is "timer for this core"
+     *  * region 1 is "watchdog for this core"
+     *  * region 2 is "timer for core 0"
+     *  * region 3 is "watchdog for core 0"
+     *  * region 4 is "timer for core 1"
+     *  * region 5 is "watchdog for core 1"
+     * and so on.
+     * The outgoing interrupt lines are
+     *  * timer for core 0
+     *  * watchdog for core 0
+     *  * timer for core 1
+     *  * watchdog for core 1
+     * and so on.
+     */
+    memory_region_init_io(&s->iomem[0], &arm_thistimer_ops, s,
+                          "arm_mptimer_timer", 0x20);
+    sysbus_init_mmio(dev, &s->iomem[0]);
+    memory_region_init_io(&s->iomem[1], &arm_thiswdog_ops, s,
+                          "arm_mptimer_wdog", 0x20);
+    sysbus_init_mmio(dev, &s->iomem[1]);
+    for (i = 0; i < (s->num_cpu * 2); i++) {
+        timerblock *tb = &s->timerblock[i];
+        tb->timer = qemu_new_timer_ns(vm_clock, timerblock_tick, tb);
+        sysbus_init_irq(dev, &tb->irq);
+        memory_region_init_io(&tb->iomem, &timerblock_ops, tb,
+                              "arm_mptimer_timerblock", 0x20);
+        sysbus_init_mmio(dev, &tb->iomem);
+    }
+
+    return 0;
+}
+
+static const VMStateDescription vmstate_timerblock = {
+    .name = "arm_mptimer_timerblock",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(count, timerblock),
+        VMSTATE_UINT32(load, timerblock),
+        VMSTATE_UINT32(control, timerblock),
+        VMSTATE_UINT32(status, timerblock),
+        VMSTATE_INT64(tick, timerblock),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static const VMStateDescription vmstate_arm_mptimer = {
+    .name = "arm_mptimer",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_STRUCT_ARRAY(timerblock, arm_mptimer_state, (MAX_CPUS * 2),
+                             1, vmstate_timerblock, timerblock),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static SysBusDeviceInfo arm_mptimer_info = {
+    .init = arm_mptimer_init,
+    .qdev.name = "arm_mptimer",
+    .qdev.size = sizeof(arm_mptimer_state),
+    .qdev.vmsd = &vmstate_arm_mptimer,
+    .qdev.reset = arm_mptimer_reset,
+    .qdev.no_user = 1,
+    .qdev.props = (Property[]) {
+        DEFINE_PROP_UINT32("num-cpu", arm_mptimer_state, num_cpu, 0),
+        DEFINE_PROP_END_OF_LIST()
+    }
+};
+
+static void arm_mptimer_register_devices(void)
+{
+    sysbus_register_withprop(&arm_mptimer_info);
+}
+
+device_init(arm_mptimer_register_devices)