From: "Philippe Mathieu-Daudé" <f4bug@amsat.org>
To: qemu-devel@nongnu.org
Cc: "Kevin Wolf" <kwolf@redhat.com>,
"Peter Maydell" <peter.maydell@linaro.org>,
qemu-block@nongnu.org, "Corey Minyard" <minyard@acm.org>,
"David Hildenbrand" <david@redhat.com>,
"Andrew Jeffery" <andrew@aj.id.au>,
"Michael S. Tsirkin" <mst@redhat.com>,
"Mark Cave-Ayland" <mark.cave-ayland@ilande.co.uk>,
"Philippe Mathieu-Daudé" <f4bug@amsat.org>,
"Max Reitz" <mreitz@redhat.com>,
qemu-arm@nongnu.org, "Joel Stanley" <joel@jms.id.au>,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Cédric Le Goater" <clg@kaod.org>
Subject: [PATCH 7/7] hw/watchdog/wdt_aspeed: Reduce timer precision to micro-second
Date: Tue, 16 Jun 2020 09:51:21 +0200 [thread overview]
Message-ID: <20200616075121.12837-8-f4bug@amsat.org> (raw)
In-Reply-To: <20200616075121.12837-1-f4bug@amsat.org>
The current implementation uses nano-second precision, while
the watchdog can not be more precise than a micro-second.
Simplify by using a micro-second based timer.
Rename the timer 'timer_us' to have the unit explicit.
Inspired-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
include/hw/watchdog/wdt_aspeed.h | 2 +-
hw/watchdog/wdt_aspeed.c | 24 +++++++++++++-----------
2 files changed, 14 insertions(+), 12 deletions(-)
diff --git a/include/hw/watchdog/wdt_aspeed.h b/include/hw/watchdog/wdt_aspeed.h
index 819c22993a..e76a493788 100644
--- a/include/hw/watchdog/wdt_aspeed.h
+++ b/include/hw/watchdog/wdt_aspeed.h
@@ -25,7 +25,7 @@
typedef struct AspeedWDTState {
/*< private >*/
SysBusDevice parent_obj;
- QEMUTimer *timer;
+ QEMUTimer *timer_us;
/*< public >*/
MemoryRegion iomem;
diff --git a/hw/watchdog/wdt_aspeed.c b/hw/watchdog/wdt_aspeed.c
index 6352ba1b0e..3fcb20f72b 100644
--- a/hw/watchdog/wdt_aspeed.c
+++ b/hw/watchdog/wdt_aspeed.c
@@ -98,23 +98,24 @@ static void aspeed_wdt_reload(AspeedWDTState *s)
uint64_t reload;
if (!(s->regs[WDT_CTRL] & WDT_CTRL_1MHZ_CLK)) {
- reload = muldiv64(s->regs[WDT_RELOAD_VALUE], NANOSECONDS_PER_SECOND,
+ reload = muldiv64(s->regs[WDT_RELOAD_VALUE],
+ NANOSECONDS_PER_SECOND / SCALE_US,
s->pclk_freq);
} else {
- reload = s->regs[WDT_RELOAD_VALUE] * 1000ULL;
+ reload = s->regs[WDT_RELOAD_VALUE];
}
if (aspeed_wdt_is_enabled(s)) {
- timer_mod(s->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + reload);
+ timer_mod(s->timer_us, qemu_clock_get_us(QEMU_CLOCK_VIRTUAL) + reload);
}
}
static void aspeed_wdt_reload_1mhz(AspeedWDTState *s)
{
- uint64_t reload = s->regs[WDT_RELOAD_VALUE] * 1000ULL;
+ uint64_t reload = s->regs[WDT_RELOAD_VALUE];
if (aspeed_wdt_is_enabled(s)) {
- timer_mod(s->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + reload);
+ timer_mod(s->timer_us, qemu_clock_get_us(QEMU_CLOCK_VIRTUAL) + reload);
}
}
@@ -149,7 +150,7 @@ static void aspeed_wdt_write(void *opaque, hwaddr offset, uint64_t data,
awc->wdt_reload(s);
} else if (!enable && aspeed_wdt_is_enabled(s)) {
s->regs[WDT_CTRL] = data;
- timer_del(s->timer);
+ timer_del(s->timer_us);
}
break;
case WDT_RESET_WIDTH:
@@ -189,7 +190,7 @@ static const VMStateDescription vmstate_aspeed_wdt = {
.version_id = 0,
.minimum_version_id = 0,
.fields = (VMStateField[]) {
- VMSTATE_TIMER_PTR(timer, AspeedWDTState),
+ VMSTATE_TIMER_PTR(timer_us, AspeedWDTState),
VMSTATE_UINT32_ARRAY(regs, AspeedWDTState, ASPEED_WDT_REGS_MAX),
VMSTATE_END_OF_LIST()
}
@@ -214,7 +215,7 @@ static void aspeed_wdt_reset(DeviceState *dev)
s->regs[WDT_CTRL] = 0;
s->regs[WDT_RESET_WIDTH] = 0xFF;
- timer_del(s->timer);
+ timer_del(s->timer_us);
}
static void aspeed_wdt_timer_expired(void *dev)
@@ -224,7 +225,7 @@ static void aspeed_wdt_timer_expired(void *dev)
/* Do not reset on SDRAM controller reset */
if (s->scu->regs[reset_ctrl_reg] & SCU_RESET_SDRAM) {
- timer_del(s->timer);
+ timer_del(s->timer_us);
s->regs[WDT_CTRL] = 0;
return;
}
@@ -232,7 +233,7 @@ static void aspeed_wdt_timer_expired(void *dev)
qemu_log_mask(CPU_LOG_RESET, "Watchdog timer %" HWADDR_PRIx " expired.\n",
s->iomem.addr);
watchdog_perform_action();
- timer_del(s->timer);
+ timer_del(s->timer_us);
}
#define PCLK_HZ 24000000
@@ -244,7 +245,8 @@ static void aspeed_wdt_realize(DeviceState *dev, Error **errp)
assert(s->scu);
- s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, aspeed_wdt_timer_expired, dev);
+ s->timer_us = timer_new_us(QEMU_CLOCK_VIRTUAL,
+ aspeed_wdt_timer_expired, dev);
/* FIXME: This setting should be derived from the SCU hw strapping
* register SCU70
--
2.21.3
next prev parent reply other threads:[~2020-06-16 7:56 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-16 7:51 [PATCH 0/7] misc: Reduce QEMUTimer pressure by using lower precision when possible Philippe Mathieu-Daudé
2020-06-16 7:51 ` [PATCH 1/7] qemu-common: Briefly document qemu_timedate_diff() unit Philippe Mathieu-Daudé
2020-06-18 5:47 ` Markus Armbruster
2020-06-22 8:50 ` Philippe Mathieu-Daudé
2020-06-16 7:51 ` [PATCH 2/7] block/qcow2: Document cache_clean_interval field holds seconds Philippe Mathieu-Daudé
2020-06-16 7:51 ` [PATCH 3/7] block/curl: Reduce timer precision to milli-second Philippe Mathieu-Daudé
2020-06-16 7:51 ` [PATCH 4/7] hw/virtio/virtio-balloon: Rename timer field including 'ms' unit Philippe Mathieu-Daudé
2020-06-16 7:57 ` David Hildenbrand
2020-06-16 7:51 ` [PATCH 5/7] hw/rtc/m48t59: Reduce timer precision to milli-second Philippe Mathieu-Daudé
2020-07-08 23:39 ` Richard Henderson
2020-06-16 7:51 ` [PATCH 6/7] hw/ipmi/ipmi_bmc_extern: " Philippe Mathieu-Daudé
2020-06-16 7:51 ` Philippe Mathieu-Daudé [this message]
2020-06-17 1:18 ` [PATCH 7/7] hw/watchdog/wdt_aspeed: Reduce timer precision to micro-second Andrew Jeffery
2020-06-17 3:41 ` Philippe Mathieu-Daudé
2020-06-22 0:21 ` Andrew Jeffery
2020-06-22 8:43 ` Philippe Mathieu-Daudé
2020-06-22 23:45 ` Andrew Jeffery
2020-07-08 23:40 ` Richard Henderson
2020-06-18 12:23 ` [PATCH 0/7] misc: Reduce QEMUTimer pressure by using lower precision when possible Paolo Bonzini
2020-06-18 12:26 ` Philippe Mathieu-Daudé
2020-06-18 12:42 ` Paolo Bonzini
2020-07-08 23:37 ` Richard Henderson
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