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-rw-r--r--src/hw/timer/cadence_ttc.c491
1 files changed, 491 insertions, 0 deletions
diff --git a/src/hw/timer/cadence_ttc.c b/src/hw/timer/cadence_ttc.c
new file mode 100644
index 0000000..35bc880
--- /dev/null
+++ b/src/hw/timer/cadence_ttc.c
@@ -0,0 +1,491 @@
+/*
+ * Xilinx Zynq cadence TTC model
+ *
+ * Copyright (c) 2011 Xilinx Inc.
+ * Copyright (c) 2012 Peter A.G. Crosthwaite (peter.crosthwaite@petalogix.com)
+ * Copyright (c) 2012 PetaLogix Pty Ltd.
+ * Written By Haibing Ma
+ * M. Habib
+ *
+ * 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.
+ *
+ * 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 "hw/sysbus.h"
+#include "qemu/timer.h"
+
+#ifdef CADENCE_TTC_ERR_DEBUG
+#define DB_PRINT(...) do { \
+ fprintf(stderr, ": %s: ", __func__); \
+ fprintf(stderr, ## __VA_ARGS__); \
+ } while (0);
+#else
+ #define DB_PRINT(...)
+#endif
+
+#define COUNTER_INTR_IV 0x00000001
+#define COUNTER_INTR_M1 0x00000002
+#define COUNTER_INTR_M2 0x00000004
+#define COUNTER_INTR_M3 0x00000008
+#define COUNTER_INTR_OV 0x00000010
+#define COUNTER_INTR_EV 0x00000020
+
+#define COUNTER_CTRL_DIS 0x00000001
+#define COUNTER_CTRL_INT 0x00000002
+#define COUNTER_CTRL_DEC 0x00000004
+#define COUNTER_CTRL_MATCH 0x00000008
+#define COUNTER_CTRL_RST 0x00000010
+
+#define CLOCK_CTRL_PS_EN 0x00000001
+#define CLOCK_CTRL_PS_V 0x0000001e
+
+typedef struct {
+ QEMUTimer *timer;
+ int freq;
+
+ uint32_t reg_clock;
+ uint32_t reg_count;
+ uint32_t reg_value;
+ uint16_t reg_interval;
+ uint16_t reg_match[3];
+ uint32_t reg_intr;
+ uint32_t reg_intr_en;
+ uint32_t reg_event_ctrl;
+ uint32_t reg_event;
+
+ uint64_t cpu_time;
+ unsigned int cpu_time_valid;
+
+ qemu_irq irq;
+} CadenceTimerState;
+
+#define TYPE_CADENCE_TTC "cadence_ttc"
+#define CADENCE_TTC(obj) \
+ OBJECT_CHECK(CadenceTTCState, (obj), TYPE_CADENCE_TTC)
+
+typedef struct CadenceTTCState {
+ SysBusDevice parent_obj;
+
+ MemoryRegion iomem;
+ CadenceTimerState timer[3];
+} CadenceTTCState;
+
+static void cadence_timer_update(CadenceTimerState *s)
+{
+ qemu_set_irq(s->irq, !!(s->reg_intr & s->reg_intr_en));
+}
+
+static CadenceTimerState *cadence_timer_from_addr(void *opaque,
+ hwaddr offset)
+{
+ unsigned int index;
+ CadenceTTCState *s = (CadenceTTCState *)opaque;
+
+ index = (offset >> 2) % 3;
+
+ return &s->timer[index];
+}
+
+static uint64_t cadence_timer_get_ns(CadenceTimerState *s, uint64_t timer_steps)
+{
+ /* timer_steps has max value of 0x100000000. double check it
+ * (or overflow can happen below) */
+ assert(timer_steps <= 1ULL << 32);
+
+ uint64_t r = timer_steps * 1000000000ULL;
+ if (s->reg_clock & CLOCK_CTRL_PS_EN) {
+ r >>= 16 - (((s->reg_clock & CLOCK_CTRL_PS_V) >> 1) + 1);
+ } else {
+ r >>= 16;
+ }
+ r /= (uint64_t)s->freq;
+ return r;
+}
+
+static uint64_t cadence_timer_get_steps(CadenceTimerState *s, uint64_t ns)
+{
+ uint64_t to_divide = 1000000000ULL;
+
+ uint64_t r = ns;
+ /* for very large intervals (> 8s) do some division first to stop
+ * overflow (costs some prescision) */
+ while (r >= 8ULL << 30 && to_divide > 1) {
+ r /= 1000;
+ to_divide /= 1000;
+ }
+ r <<= 16;
+ /* keep early-dividing as needed */
+ while (r >= 8ULL << 30 && to_divide > 1) {
+ r /= 1000;
+ to_divide /= 1000;
+ }
+ r *= (uint64_t)s->freq;
+ if (s->reg_clock & CLOCK_CTRL_PS_EN) {
+ r /= 1 << (((s->reg_clock & CLOCK_CTRL_PS_V) >> 1) + 1);
+ }
+
+ r /= to_divide;
+ return r;
+}
+
+/* determine if x is in between a and b, exclusive of a, inclusive of b */
+
+static inline int64_t is_between(int64_t x, int64_t a, int64_t b)
+{
+ if (a < b) {
+ return x > a && x <= b;
+ }
+ return x < a && x >= b;
+}
+
+static void cadence_timer_run(CadenceTimerState *s)
+{
+ int i;
+ int64_t event_interval, next_value;
+
+ assert(s->cpu_time_valid); /* cadence_timer_sync must be called first */
+
+ if (s->reg_count & COUNTER_CTRL_DIS) {
+ s->cpu_time_valid = 0;
+ return;
+ }
+
+ { /* figure out what's going to happen next (rollover or match) */
+ int64_t interval = (uint64_t)((s->reg_count & COUNTER_CTRL_INT) ?
+ (int64_t)s->reg_interval + 1 : 0x10000ULL) << 16;
+ next_value = (s->reg_count & COUNTER_CTRL_DEC) ? -1ULL : interval;
+ for (i = 0; i < 3; ++i) {
+ int64_t cand = (uint64_t)s->reg_match[i] << 16;
+ if (is_between(cand, (uint64_t)s->reg_value, next_value)) {
+ next_value = cand;
+ }
+ }
+ }
+ DB_PRINT("next timer event value: %09llx\n",
+ (unsigned long long)next_value);
+
+ event_interval = next_value - (int64_t)s->reg_value;
+ event_interval = (event_interval < 0) ? -event_interval : event_interval;
+
+ timer_mod(s->timer, s->cpu_time +
+ cadence_timer_get_ns(s, event_interval));
+}
+
+static void cadence_timer_sync(CadenceTimerState *s)
+{
+ int i;
+ int64_t r, x;
+ int64_t interval = ((s->reg_count & COUNTER_CTRL_INT) ?
+ (int64_t)s->reg_interval + 1 : 0x10000ULL) << 16;
+ uint64_t old_time = s->cpu_time;
+
+ s->cpu_time = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+ DB_PRINT("cpu time: %lld ns\n", (long long)old_time);
+
+ if (!s->cpu_time_valid || old_time == s->cpu_time) {
+ s->cpu_time_valid = 1;
+ return;
+ }
+
+ r = (int64_t)cadence_timer_get_steps(s, s->cpu_time - old_time);
+ x = (int64_t)s->reg_value + ((s->reg_count & COUNTER_CTRL_DEC) ? -r : r);
+
+ for (i = 0; i < 3; ++i) {
+ int64_t m = (int64_t)s->reg_match[i] << 16;
+ if (m > interval) {
+ continue;
+ }
+ /* check to see if match event has occurred. check m +/- interval
+ * to account for match events in wrap around cases */
+ if (is_between(m, s->reg_value, x) ||
+ is_between(m + interval, s->reg_value, x) ||
+ is_between(m - interval, s->reg_value, x)) {
+ s->reg_intr |= (2 << i);
+ }
+ }
+ if ((x < 0) || (x >= interval)) {
+ s->reg_intr |= (s->reg_count & COUNTER_CTRL_INT) ?
+ COUNTER_INTR_IV : COUNTER_INTR_OV;
+ }
+ while (x < 0) {
+ x += interval;
+ }
+ s->reg_value = (uint32_t)(x % interval);
+ cadence_timer_update(s);
+}
+
+static void cadence_timer_tick(void *opaque)
+{
+ CadenceTimerState *s = opaque;
+
+ DB_PRINT("\n");
+ cadence_timer_sync(s);
+ cadence_timer_run(s);
+}
+
+static uint32_t cadence_ttc_read_imp(void *opaque, hwaddr offset)
+{
+ CadenceTimerState *s = cadence_timer_from_addr(opaque, offset);
+ uint32_t value;
+
+ cadence_timer_sync(s);
+ cadence_timer_run(s);
+
+ switch (offset) {
+ case 0x00: /* clock control */
+ case 0x04:
+ case 0x08:
+ return s->reg_clock;
+
+ case 0x0c: /* counter control */
+ case 0x10:
+ case 0x14:
+ return s->reg_count;
+
+ case 0x18: /* counter value */
+ case 0x1c:
+ case 0x20:
+ return (uint16_t)(s->reg_value >> 16);
+
+ case 0x24: /* reg_interval counter */
+ case 0x28:
+ case 0x2c:
+ return s->reg_interval;
+
+ case 0x30: /* match 1 counter */
+ case 0x34:
+ case 0x38:
+ return s->reg_match[0];
+
+ case 0x3c: /* match 2 counter */
+ case 0x40:
+ case 0x44:
+ return s->reg_match[1];
+
+ case 0x48: /* match 3 counter */
+ case 0x4c:
+ case 0x50:
+ return s->reg_match[2];
+
+ case 0x54: /* interrupt register */
+ case 0x58:
+ case 0x5c:
+ /* cleared after read */
+ value = s->reg_intr;
+ s->reg_intr = 0;
+ cadence_timer_update(s);
+ return value;
+
+ case 0x60: /* interrupt enable */
+ case 0x64:
+ case 0x68:
+ return s->reg_intr_en;
+
+ case 0x6c:
+ case 0x70:
+ case 0x74:
+ return s->reg_event_ctrl;
+
+ case 0x78:
+ case 0x7c:
+ case 0x80:
+ return s->reg_event;
+
+ default:
+ return 0;
+ }
+}
+
+static uint64_t cadence_ttc_read(void *opaque, hwaddr offset,
+ unsigned size)
+{
+ uint32_t ret = cadence_ttc_read_imp(opaque, offset);
+
+ DB_PRINT("addr: %08x data: %08x\n", (unsigned)offset, (unsigned)ret);
+ return ret;
+}
+
+static void cadence_ttc_write(void *opaque, hwaddr offset,
+ uint64_t value, unsigned size)
+{
+ CadenceTimerState *s = cadence_timer_from_addr(opaque, offset);
+
+ DB_PRINT("addr: %08x data %08x\n", (unsigned)offset, (unsigned)value);
+
+ cadence_timer_sync(s);
+
+ switch (offset) {
+ case 0x00: /* clock control */
+ case 0x04:
+ case 0x08:
+ s->reg_clock = value & 0x3F;
+ break;
+
+ case 0x0c: /* counter control */
+ case 0x10:
+ case 0x14:
+ if (value & COUNTER_CTRL_RST) {
+ s->reg_value = 0;
+ }
+ s->reg_count = value & 0x3f & ~COUNTER_CTRL_RST;
+ break;
+
+ case 0x24: /* interval register */
+ case 0x28:
+ case 0x2c:
+ s->reg_interval = value & 0xffff;
+ break;
+
+ case 0x30: /* match register */
+ case 0x34:
+ case 0x38:
+ s->reg_match[0] = value & 0xffff;
+ break;
+
+ case 0x3c: /* match register */
+ case 0x40:
+ case 0x44:
+ s->reg_match[1] = value & 0xffff;
+ break;
+
+ case 0x48: /* match register */
+ case 0x4c:
+ case 0x50:
+ s->reg_match[2] = value & 0xffff;
+ break;
+
+ case 0x54: /* interrupt register */
+ case 0x58:
+ case 0x5c:
+ break;
+
+ case 0x60: /* interrupt enable */
+ case 0x64:
+ case 0x68:
+ s->reg_intr_en = value & 0x3f;
+ break;
+
+ case 0x6c: /* event control */
+ case 0x70:
+ case 0x74:
+ s->reg_event_ctrl = value & 0x07;
+ break;
+
+ default:
+ return;
+ }
+
+ cadence_timer_run(s);
+ cadence_timer_update(s);
+}
+
+static const MemoryRegionOps cadence_ttc_ops = {
+ .read = cadence_ttc_read,
+ .write = cadence_ttc_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static void cadence_timer_reset(CadenceTimerState *s)
+{
+ s->reg_count = 0x21;
+}
+
+static void cadence_timer_init(uint32_t freq, CadenceTimerState *s)
+{
+ memset(s, 0, sizeof(CadenceTimerState));
+ s->freq = freq;
+
+ cadence_timer_reset(s);
+
+ s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, cadence_timer_tick, s);
+}
+
+static void cadence_ttc_init(Object *obj)
+{
+ CadenceTTCState *s = CADENCE_TTC(obj);
+ int i;
+
+ for (i = 0; i < 3; ++i) {
+ cadence_timer_init(133000000, &s->timer[i]);
+ sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->timer[i].irq);
+ }
+
+ memory_region_init_io(&s->iomem, obj, &cadence_ttc_ops, s,
+ "timer", 0x1000);
+ sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->iomem);
+}
+
+static void cadence_timer_pre_save(void *opaque)
+{
+ cadence_timer_sync((CadenceTimerState *)opaque);
+}
+
+static int cadence_timer_post_load(void *opaque, int version_id)
+{
+ CadenceTimerState *s = opaque;
+
+ s->cpu_time_valid = 0;
+ cadence_timer_sync(s);
+ cadence_timer_run(s);
+ cadence_timer_update(s);
+ return 0;
+}
+
+static const VMStateDescription vmstate_cadence_timer = {
+ .name = "cadence_timer",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .pre_save = cadence_timer_pre_save,
+ .post_load = cadence_timer_post_load,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32(reg_clock, CadenceTimerState),
+ VMSTATE_UINT32(reg_count, CadenceTimerState),
+ VMSTATE_UINT32(reg_value, CadenceTimerState),
+ VMSTATE_UINT16(reg_interval, CadenceTimerState),
+ VMSTATE_UINT16_ARRAY(reg_match, CadenceTimerState, 3),
+ VMSTATE_UINT32(reg_intr, CadenceTimerState),
+ VMSTATE_UINT32(reg_intr_en, CadenceTimerState),
+ VMSTATE_UINT32(reg_event_ctrl, CadenceTimerState),
+ VMSTATE_UINT32(reg_event, CadenceTimerState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static const VMStateDescription vmstate_cadence_ttc = {
+ .name = "cadence_TTC",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_STRUCT_ARRAY(timer, CadenceTTCState, 3, 0,
+ vmstate_cadence_timer,
+ CadenceTimerState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static void cadence_ttc_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->vmsd = &vmstate_cadence_ttc;
+}
+
+static const TypeInfo cadence_ttc_info = {
+ .name = TYPE_CADENCE_TTC,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(CadenceTTCState),
+ .instance_init = cadence_ttc_init,
+ .class_init = cadence_ttc_class_init,
+};
+
+static void cadence_ttc_register_types(void)
+{
+ type_register_static(&cadence_ttc_info);
+}
+
+type_init(cadence_ttc_register_types)
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