blob: 435142a3c91fb7d5e28231c50d20b7e8e7d9170c [file] [log] [blame]
/*
* Global peripheral timer block for ARM A9MP
*
* (C) 2013 Xilinx Inc.
*
* Written by François LEGAL
* Written by Peter Crosthwaite <peter.crosthwaite@xilinx.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 "hw/timer/a9gtimer.h"
#include "qemu/timer.h"
#include "qemu/bitops.h"
#include "qemu/log.h"
#ifndef A9_GTIMER_ERR_DEBUG
#define A9_GTIMER_ERR_DEBUG 0
#endif
#define DB_PRINT_L(level, ...) do { \
if (A9_GTIMER_ERR_DEBUG > (level)) { \
fprintf(stderr, ": %s: ", __func__); \
fprintf(stderr, ## __VA_ARGS__); \
} \
} while (0);
#define DB_PRINT(...) DB_PRINT_L(0, ## __VA_ARGS__)
static inline int a9_gtimer_get_current_cpu(A9GTimerState *s)
{
if (current_cpu->cpu_index >= s->num_cpu) {
hw_error("a9gtimer: num-cpu %d but this cpu is %d!\n",
s->num_cpu, current_cpu->cpu_index);
}
return current_cpu->cpu_index;
}
static inline uint64_t a9_gtimer_get_conv(A9GTimerState *s)
{
uint64_t prescale = extract32(s->control, R_CONTROL_PRESCALER_SHIFT,
R_CONTROL_PRESCALER_LEN);
return (prescale + 1) * 10;
}
static A9GTimerUpdate a9_gtimer_get_update(A9GTimerState *s)
{
A9GTimerUpdate ret;
ret.now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
ret.new = s->ref_counter +
(ret.now - s->cpu_ref_time) / a9_gtimer_get_conv(s);
return ret;
}
static void a9_gtimer_update(A9GTimerState *s, bool sync)
{
A9GTimerUpdate update = a9_gtimer_get_update(s);
int i;
int64_t next_cdiff = 0;
for (i = 0; i < s->num_cpu; ++i) {
A9GTimerPerCPU *gtb = &s->per_cpu[i];
int64_t cdiff = 0;
if ((s->control & R_CONTROL_TIMER_ENABLE) &&
(gtb->control & R_CONTROL_COMP_ENABLE)) {
/* R2p0+, where the compare function is >= */
while (gtb->compare < update.new) {
DB_PRINT("Compare event happened for CPU %d\n", i);
gtb->status = 1;
if (gtb->control & R_CONTROL_AUTO_INCREMENT) {
DB_PRINT("Auto incrementing timer compare by %" PRId32 "\n",
gtb->inc);
gtb->compare += gtb->inc;
} else {
break;
}
}
cdiff = (int64_t)gtb->compare - (int64_t)update.new + 1;
if (cdiff > 0 && (cdiff < next_cdiff || !next_cdiff)) {
next_cdiff = cdiff;
}
}
qemu_set_irq(gtb->irq,
gtb->status && (gtb->control & R_CONTROL_IRQ_ENABLE));
}
timer_del(s->timer);
if (next_cdiff) {
DB_PRINT("scheduling qemu_timer to fire again in %"
PRIx64 " cycles\n", next_cdiff);
timer_mod(s->timer, update.now + next_cdiff * a9_gtimer_get_conv(s));
}
if (s->control & R_CONTROL_TIMER_ENABLE) {
s->counter = update.new;
}
if (sync) {
s->cpu_ref_time = update.now;
s->ref_counter = s->counter;
}
}
static void a9_gtimer_update_no_sync(void *opaque)
{
A9GTimerState *s = A9_GTIMER(opaque);
return a9_gtimer_update(s, false);
}
static uint64_t a9_gtimer_read(void *opaque, hwaddr addr, unsigned size)
{
A9GTimerPerCPU *gtb = (A9GTimerPerCPU *)opaque;
A9GTimerState *s = gtb->parent;
A9GTimerUpdate update;
uint64_t ret = 0;
int shift = 0;
switch (addr) {
case R_COUNTER_HI:
shift = 32;
/* fallthrough */
case R_COUNTER_LO:
update = a9_gtimer_get_update(s);
ret = extract64(update.new, shift, 32);
break;
case R_CONTROL:
ret = s->control | gtb->control;
break;
case R_INTERRUPT_STATUS:
ret = gtb->status;
break;
case R_COMPARATOR_HI:
shift = 32;
/* fallthrough */
case R_COMPARATOR_LO:
ret = extract64(gtb->compare, shift, 32);
break;
case R_AUTO_INCREMENT:
ret = gtb->inc;
break;
default:
qemu_log_mask(LOG_GUEST_ERROR, "bad a9gtimer register: %x\n",
(unsigned)addr);
return 0;
}
DB_PRINT("addr:%#x data:%#08" PRIx64 "\n", (unsigned)addr, ret);
return ret;
}
static void a9_gtimer_write(void *opaque, hwaddr addr, uint64_t value,
unsigned size)
{
A9GTimerPerCPU *gtb = (A9GTimerPerCPU *)opaque;
A9GTimerState *s = gtb->parent;
int shift = 0;
DB_PRINT("addr:%#x data:%#08" PRIx64 "\n", (unsigned)addr, value);
switch (addr) {
case R_COUNTER_HI:
shift = 32;
/* fallthrough */
case R_COUNTER_LO:
/*
* Keep it simple - ARM docco explicitly says to disable timer before
* modding it, so dont bother trying to do all the difficult on the fly
* timer modifications - (if they even work in real hardware??).
*/
if (s->control & R_CONTROL_TIMER_ENABLE) {
qemu_log_mask(LOG_GUEST_ERROR, "Cannot mod running ARM gtimer\n");
return;
}
s->counter = deposit64(s->counter, shift, 32, value);
return;
case R_CONTROL:
a9_gtimer_update(s, (value ^ s->control) & R_CONTROL_NEEDS_SYNC);
gtb->control = value & R_CONTROL_BANKED;
s->control = value & ~R_CONTROL_BANKED;
break;
case R_INTERRUPT_STATUS:
a9_gtimer_update(s, false);
gtb->status &= ~value;
break;
case R_COMPARATOR_HI:
shift = 32;
/* fallthrough */
case R_COMPARATOR_LO:
a9_gtimer_update(s, false);
gtb->compare = deposit64(gtb->compare, shift, 32, value);
break;
case R_AUTO_INCREMENT:
gtb->inc = value;
return;
default:
return;
}
a9_gtimer_update(s, false);
}
/* Wrapper functions to implement the "read global timer for
* the current CPU" memory regions.
*/
static uint64_t a9_gtimer_this_read(void *opaque, hwaddr addr,
unsigned size)
{
A9GTimerState *s = A9_GTIMER(opaque);
int id = a9_gtimer_get_current_cpu(s);
/* no \n so concatenates with message from read fn */
DB_PRINT("CPU:%d:", id);
return a9_gtimer_read(&s->per_cpu[id], addr, size);
}
static void a9_gtimer_this_write(void *opaque, hwaddr addr,
uint64_t value, unsigned size)
{
A9GTimerState *s = A9_GTIMER(opaque);
int id = a9_gtimer_get_current_cpu(s);
/* no \n so concatenates with message from write fn */
DB_PRINT("CPU:%d:", id);
a9_gtimer_write(&s->per_cpu[id], addr, value, size);
}
static const MemoryRegionOps a9_gtimer_this_ops = {
.read = a9_gtimer_this_read,
.write = a9_gtimer_this_write,
.valid = {
.min_access_size = 4,
.max_access_size = 4,
},
.endianness = DEVICE_NATIVE_ENDIAN,
};
static const MemoryRegionOps a9_gtimer_ops = {
.read = a9_gtimer_read,
.write = a9_gtimer_write,
.valid = {
.min_access_size = 4,
.max_access_size = 4,
},
.endianness = DEVICE_NATIVE_ENDIAN,
};
static void a9_gtimer_reset(DeviceState *dev)
{
A9GTimerState *s = A9_GTIMER(dev);
int i;
s->counter = 0;
s->control = 0;
for (i = 0; i < s->num_cpu; i++) {
A9GTimerPerCPU *gtb = &s->per_cpu[i];
gtb->control = 0;
gtb->status = 0;
gtb->compare = 0;
gtb->inc = 0;
}
a9_gtimer_update(s, false);
}
static void a9_gtimer_realize(DeviceState *dev, Error **errp)
{
A9GTimerState *s = A9_GTIMER(dev);
SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
int i;
if (s->num_cpu < 1 || s->num_cpu > A9_GTIMER_MAX_CPUS) {
error_setg(errp, "%s: num-cpu must be between 1 and %d\n",
__func__, A9_GTIMER_MAX_CPUS);
return;
}
memory_region_init_io(&s->iomem, OBJECT(dev), &a9_gtimer_this_ops, s,
"a9gtimer shared", 0x20);
sysbus_init_mmio(sbd, &s->iomem);
s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, a9_gtimer_update_no_sync, s);
for (i = 0; i < s->num_cpu; i++) {
A9GTimerPerCPU *gtb = &s->per_cpu[i];
gtb->parent = s;
sysbus_init_irq(sbd, &gtb->irq);
memory_region_init_io(&gtb->iomem, OBJECT(dev), &a9_gtimer_ops, gtb,
"a9gtimer per cpu", 0x20);
sysbus_init_mmio(sbd, &gtb->iomem);
}
}
static const VMStateDescription vmstate_a9_gtimer_per_cpu = {
.name = "arm.cortex-a9-global-timer.percpu",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_UINT32(control, A9GTimerPerCPU),
VMSTATE_UINT64(compare, A9GTimerPerCPU),
VMSTATE_UINT32(status, A9GTimerPerCPU),
VMSTATE_UINT32(inc, A9GTimerPerCPU),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_a9_gtimer = {
.name = "arm.cortex-a9-global-timer",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_TIMER_PTR(timer, A9GTimerState),
VMSTATE_UINT64(counter, A9GTimerState),
VMSTATE_UINT64(ref_counter, A9GTimerState),
VMSTATE_UINT64(cpu_ref_time, A9GTimerState),
VMSTATE_STRUCT_VARRAY_UINT32(per_cpu, A9GTimerState, num_cpu,
1, vmstate_a9_gtimer_per_cpu,
A9GTimerPerCPU),
VMSTATE_END_OF_LIST()
}
};
static Property a9_gtimer_properties[] = {
DEFINE_PROP_UINT32("num-cpu", A9GTimerState, num_cpu, 0),
DEFINE_PROP_END_OF_LIST()
};
static void a9_gtimer_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = a9_gtimer_realize;
dc->vmsd = &vmstate_a9_gtimer;
dc->reset = a9_gtimer_reset;
dc->props = a9_gtimer_properties;
}
static const TypeInfo a9_gtimer_info = {
.name = TYPE_A9_GTIMER,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(A9GTimerState),
.class_init = a9_gtimer_class_init,
};
static void a9_gtimer_register_types(void)
{
type_register_static(&a9_gtimer_info);
}
type_init(a9_gtimer_register_types)