mirror of https://gitee.com/openkylin/qemu.git
hw/timer: Add value matching support to aspeed_timer
Value matching allows Linux to boot with CONFIG_NO_HZ_IDLE=y on the palmetto-bmc machine. Two match registers are provided for each timer. Signed-off-by: Andrew Jeffery <andrew@aj.id.au> Message-id: 1465974248-20434-1-git-send-email-andrew@aj.id.au Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Andrew Jeffery
Peter Maydell
parent
3b1a222501
commit
1d3e65aa7a
|
|
@ -10,12 +10,10 @@
|
|||
*/
|
||||
|
||||
#include "qemu/osdep.h"
|
||||
#include "hw/ptimer.h"
|
||||
#include "hw/sysbus.h"
|
||||
#include "hw/timer/aspeed_timer.h"
|
||||
#include "qemu-common.h"
|
||||
#include "qemu/bitops.h"
|
||||
#include "qemu/main-loop.h"
|
||||
#include "qemu/timer.h"
|
||||
#include "qemu/log.h"
|
||||
#include "trace.h"
|
||||
|
|
@ -77,21 +75,96 @@ static inline bool timer_can_pulse(AspeedTimer *t)
|
|||
return t->id >= TIMER_FIRST_CAP_PULSE;
|
||||
}
|
||||
|
||||
static inline bool timer_external_clock(AspeedTimer *t)
|
||||
{
|
||||
return timer_ctrl_status(t, op_external_clock);
|
||||
}
|
||||
|
||||
static uint32_t clock_rates[] = { TIMER_CLOCK_APB_HZ, TIMER_CLOCK_EXT_HZ };
|
||||
|
||||
static inline uint32_t calculate_rate(struct AspeedTimer *t)
|
||||
{
|
||||
return clock_rates[timer_external_clock(t)];
|
||||
}
|
||||
|
||||
static inline uint32_t calculate_ticks(struct AspeedTimer *t, uint64_t now_ns)
|
||||
{
|
||||
uint64_t delta_ns = now_ns - MIN(now_ns, t->start);
|
||||
uint32_t rate = calculate_rate(t);
|
||||
uint64_t ticks = muldiv64(delta_ns, rate, NANOSECONDS_PER_SECOND);
|
||||
|
||||
return t->reload - MIN(t->reload, ticks);
|
||||
}
|
||||
|
||||
static inline uint64_t calculate_time(struct AspeedTimer *t, uint32_t ticks)
|
||||
{
|
||||
uint64_t delta_ns;
|
||||
uint64_t delta_ticks;
|
||||
|
||||
delta_ticks = t->reload - MIN(t->reload, ticks);
|
||||
delta_ns = muldiv64(delta_ticks, NANOSECONDS_PER_SECOND, calculate_rate(t));
|
||||
|
||||
return t->start + delta_ns;
|
||||
}
|
||||
|
||||
static uint64_t calculate_next(struct AspeedTimer *t)
|
||||
{
|
||||
uint64_t next = 0;
|
||||
uint32_t rate = calculate_rate(t);
|
||||
|
||||
while (!next) {
|
||||
/* We don't know the relationship between the values in the match
|
||||
* registers, so sort using MAX/MIN/zero. We sort in that order as the
|
||||
* timer counts down to zero. */
|
||||
uint64_t seq[] = {
|
||||
calculate_time(t, MAX(t->match[0], t->match[1])),
|
||||
calculate_time(t, MIN(t->match[0], t->match[1])),
|
||||
calculate_time(t, 0),
|
||||
};
|
||||
uint64_t reload_ns;
|
||||
uint64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
|
||||
|
||||
if (now < seq[0]) {
|
||||
next = seq[0];
|
||||
} else if (now < seq[1]) {
|
||||
next = seq[1];
|
||||
} else if (now < seq[2]) {
|
||||
next = seq[2];
|
||||
} else {
|
||||
reload_ns = muldiv64(t->reload, NANOSECONDS_PER_SECOND, rate);
|
||||
t->start = now - ((now - t->start) % reload_ns);
|
||||
}
|
||||
}
|
||||
|
||||
return next;
|
||||
}
|
||||
|
||||
static void aspeed_timer_expire(void *opaque)
|
||||
{
|
||||
AspeedTimer *t = opaque;
|
||||
bool interrupt = false;
|
||||
uint32_t ticks;
|
||||
|
||||
/* Only support interrupts on match values of zero for the moment - this is
|
||||
* sufficient to boot an aspeed_defconfig Linux kernel.
|
||||
*
|
||||
* TODO: matching on arbitrary values (see e.g. hw/timer/a9gtimer.c)
|
||||
*/
|
||||
bool match = !(t->match[0] && t->match[1]);
|
||||
bool interrupt = timer_overflow_interrupt(t) || match;
|
||||
if (timer_enabled(t) && interrupt) {
|
||||
if (!timer_enabled(t)) {
|
||||
return;
|
||||
}
|
||||
|
||||
ticks = calculate_ticks(t, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
|
||||
|
||||
if (!ticks) {
|
||||
interrupt = timer_overflow_interrupt(t) || !t->match[0] || !t->match[1];
|
||||
} else if (ticks <= MIN(t->match[0], t->match[1])) {
|
||||
interrupt = true;
|
||||
} else if (ticks <= MAX(t->match[0], t->match[1])) {
|
||||
interrupt = true;
|
||||
}
|
||||
|
||||
if (interrupt) {
|
||||
t->level = !t->level;
|
||||
qemu_set_irq(t->irq, t->level);
|
||||
}
|
||||
|
||||
timer_mod(&t->timer, calculate_next(t));
|
||||
}
|
||||
|
||||
static uint64_t aspeed_timer_get_value(AspeedTimer *t, int reg)
|
||||
|
|
@ -100,7 +173,7 @@ static uint64_t aspeed_timer_get_value(AspeedTimer *t, int reg)
|
|||
|
||||
switch (reg) {
|
||||
case TIMER_REG_STATUS:
|
||||
value = ptimer_get_count(t->timer);
|
||||
value = calculate_ticks(t, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
|
||||
break;
|
||||
case TIMER_REG_RELOAD:
|
||||
value = t->reload;
|
||||
|
|
@ -160,24 +233,22 @@ static void aspeed_timer_set_value(AspeedTimerCtrlState *s, int timer, int reg,
|
|||
switch (reg) {
|
||||
case TIMER_REG_STATUS:
|
||||
if (timer_enabled(t)) {
|
||||
ptimer_set_count(t->timer, value);
|
||||
uint64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
|
||||
int64_t delta = (int64_t) value - (int64_t) calculate_ticks(t, now);
|
||||
uint32_t rate = calculate_rate(t);
|
||||
|
||||
t->start += muldiv64(delta, NANOSECONDS_PER_SECOND, rate);
|
||||
timer_mod(&t->timer, calculate_next(t));
|
||||
}
|
||||
break;
|
||||
case TIMER_REG_RELOAD:
|
||||
t->reload = value;
|
||||
ptimer_set_limit(t->timer, value, 1);
|
||||
break;
|
||||
case TIMER_REG_MATCH_FIRST:
|
||||
case TIMER_REG_MATCH_SECOND:
|
||||
if (value) {
|
||||
/* Non-zero match values are unsupported. As such an interrupt will
|
||||
* always be triggered when the timer reaches zero even if the
|
||||
* overflow interrupt control bit is clear.
|
||||
*/
|
||||
qemu_log_mask(LOG_UNIMP, "%s: Match value unsupported by device: "
|
||||
"0x%" PRIx32 "\n", __func__, value);
|
||||
} else {
|
||||
t->match[reg - 2] = value;
|
||||
t->match[reg - 2] = value;
|
||||
if (timer_enabled(t)) {
|
||||
timer_mod(&t->timer, calculate_next(t));
|
||||
}
|
||||
break;
|
||||
default:
|
||||
|
|
@ -196,21 +267,16 @@ static void aspeed_timer_ctrl_enable(AspeedTimer *t, bool enable)
|
|||
{
|
||||
trace_aspeed_timer_ctrl_enable(t->id, enable);
|
||||
if (enable) {
|
||||
ptimer_run(t->timer, 0);
|
||||
t->start = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
|
||||
timer_mod(&t->timer, calculate_next(t));
|
||||
} else {
|
||||
ptimer_stop(t->timer);
|
||||
ptimer_set_limit(t->timer, t->reload, 1);
|
||||
timer_del(&t->timer);
|
||||
}
|
||||
}
|
||||
|
||||
static void aspeed_timer_ctrl_external_clock(AspeedTimer *t, bool enable)
|
||||
{
|
||||
trace_aspeed_timer_ctrl_external_clock(t->id, enable);
|
||||
if (enable) {
|
||||
ptimer_set_freq(t->timer, TIMER_CLOCK_EXT_HZ);
|
||||
} else {
|
||||
ptimer_set_freq(t->timer, TIMER_CLOCK_APB_HZ);
|
||||
}
|
||||
}
|
||||
|
||||
static void aspeed_timer_ctrl_overflow_interrupt(AspeedTimer *t, bool enable)
|
||||
|
|
@ -351,12 +417,10 @@ static const MemoryRegionOps aspeed_timer_ops = {
|
|||
|
||||
static void aspeed_init_one_timer(AspeedTimerCtrlState *s, uint8_t id)
|
||||
{
|
||||
QEMUBH *bh;
|
||||
AspeedTimer *t = &s->timers[id];
|
||||
|
||||
t->id = id;
|
||||
bh = qemu_bh_new(aspeed_timer_expire, t);
|
||||
t->timer = ptimer_init(bh);
|
||||
timer_init_ns(&t->timer, QEMU_CLOCK_VIRTUAL, aspeed_timer_expire, t);
|
||||
}
|
||||
|
||||
static void aspeed_timer_realize(DeviceState *dev, Error **errp)
|
||||
|
|
@ -399,12 +463,12 @@ static void aspeed_timer_reset(DeviceState *dev)
|
|||
|
||||
static const VMStateDescription vmstate_aspeed_timer = {
|
||||
.name = "aspeed.timer",
|
||||
.version_id = 1,
|
||||
.minimum_version_id = 1,
|
||||
.version_id = 2,
|
||||
.minimum_version_id = 2,
|
||||
.fields = (VMStateField[]) {
|
||||
VMSTATE_UINT8(id, AspeedTimer),
|
||||
VMSTATE_INT32(level, AspeedTimer),
|
||||
VMSTATE_PTIMER(timer, AspeedTimer),
|
||||
VMSTATE_TIMER(timer, AspeedTimer),
|
||||
VMSTATE_UINT32(reload, AspeedTimer),
|
||||
VMSTATE_UINT32_ARRAY(match, AspeedTimer, 2),
|
||||
VMSTATE_END_OF_LIST()
|
||||
|
|
@ -419,7 +483,7 @@ static const VMStateDescription vmstate_aspeed_timer_state = {
|
|||
VMSTATE_UINT32(ctrl, AspeedTimerCtrlState),
|
||||
VMSTATE_UINT32(ctrl2, AspeedTimerCtrlState),
|
||||
VMSTATE_STRUCT_ARRAY(timers, AspeedTimerCtrlState,
|
||||
ASPEED_TIMER_NR_TIMERS, 1, vmstate_aspeed_timer,
|
||||
ASPEED_TIMER_NR_TIMERS, 2, vmstate_aspeed_timer,
|
||||
AspeedTimer),
|
||||
VMSTATE_END_OF_LIST()
|
||||
}
|
||||
|
|
|
|||
|
|
@ -22,7 +22,7 @@
|
|||
#ifndef ASPEED_TIMER_H
|
||||
#define ASPEED_TIMER_H
|
||||
|
||||
#include "hw/ptimer.h"
|
||||
#include "qemu/timer.h"
|
||||
|
||||
#define ASPEED_TIMER(obj) \
|
||||
OBJECT_CHECK(AspeedTimerCtrlState, (obj), TYPE_ASPEED_TIMER);
|
||||
|
|
@ -33,15 +33,16 @@ typedef struct AspeedTimer {
|
|||
qemu_irq irq;
|
||||
|
||||
uint8_t id;
|
||||
QEMUTimer timer;
|
||||
|
||||
/**
|
||||
* Track the line level as the ASPEED timers implement edge triggered
|
||||
* interrupts, signalling with both the rising and falling edge.
|
||||
*/
|
||||
int32_t level;
|
||||
ptimer_state *timer;
|
||||
uint32_t reload;
|
||||
uint32_t match[2];
|
||||
uint64_t start;
|
||||
} AspeedTimer;
|
||||
|
||||
typedef struct AspeedTimerCtrlState {
|
||||
|
|
|
|||
Loading…
Reference in New Issue