qemu/hw/timer/stm32f2xx_timer.c
Philippe Mathieu-Daudé dd1545a3f0 hw/timer/stm32f2xx_timer: Remove dead assignment
Fix warning reported by Clang static code analyzer:

    CC      hw/timer/stm32f2xx_timer.o
  hw/timer/stm32f2xx_timer.c:225:9: warning: Value stored to 'value' is never read
          value = timer_val;
          ^       ~~~~~~~~~

Reported-by: Clang Static Analyzer
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200422133152.16770-9-philmd@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2020-05-04 14:43:24 +02:00

348 lines
10 KiB
C

/*
* STM32F2XX Timer
*
* Copyright (c) 2014 Alistair Francis <alistair@alistair23.me>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "hw/irq.h"
#include "hw/qdev-properties.h"
#include "hw/timer/stm32f2xx_timer.h"
#include "migration/vmstate.h"
#include "qemu/log.h"
#include "qemu/module.h"
#ifndef STM_TIMER_ERR_DEBUG
#define STM_TIMER_ERR_DEBUG 0
#endif
#define DB_PRINT_L(lvl, fmt, args...) do { \
if (STM_TIMER_ERR_DEBUG >= lvl) { \
qemu_log("%s: " fmt, __func__, ## args); \
} \
} while (0)
#define DB_PRINT(fmt, args...) DB_PRINT_L(1, fmt, ## args)
static void stm32f2xx_timer_set_alarm(STM32F2XXTimerState *s, int64_t now);
static void stm32f2xx_timer_interrupt(void *opaque)
{
STM32F2XXTimerState *s = opaque;
DB_PRINT("Interrupt\n");
if (s->tim_dier & TIM_DIER_UIE && s->tim_cr1 & TIM_CR1_CEN) {
s->tim_sr |= 1;
qemu_irq_pulse(s->irq);
stm32f2xx_timer_set_alarm(s, s->hit_time);
}
if (s->tim_ccmr1 & (TIM_CCMR1_OC2M2 | TIM_CCMR1_OC2M1) &&
!(s->tim_ccmr1 & TIM_CCMR1_OC2M0) &&
s->tim_ccmr1 & TIM_CCMR1_OC2PE &&
s->tim_ccer & TIM_CCER_CC2E) {
/* PWM 2 - Mode 1 */
DB_PRINT("PWM2 Duty Cycle: %d%%\n",
s->tim_ccr2 / (100 * (s->tim_psc + 1)));
}
}
static inline int64_t stm32f2xx_ns_to_ticks(STM32F2XXTimerState *s, int64_t t)
{
return muldiv64(t, s->freq_hz, 1000000000ULL) / (s->tim_psc + 1);
}
static void stm32f2xx_timer_set_alarm(STM32F2XXTimerState *s, int64_t now)
{
uint64_t ticks;
int64_t now_ticks;
if (s->tim_arr == 0) {
return;
}
DB_PRINT("Alarm set at: 0x%x\n", s->tim_cr1);
now_ticks = stm32f2xx_ns_to_ticks(s, now);
ticks = s->tim_arr - (now_ticks - s->tick_offset);
DB_PRINT("Alarm set in %d ticks\n", (int) ticks);
s->hit_time = muldiv64((ticks + (uint64_t) now_ticks) * (s->tim_psc + 1),
1000000000ULL, s->freq_hz);
timer_mod(s->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + s->hit_time);
DB_PRINT("Wait Time: %" PRId64 " ticks\n", s->hit_time);
}
static void stm32f2xx_timer_reset(DeviceState *dev)
{
STM32F2XXTimerState *s = STM32F2XXTIMER(dev);
int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
s->tim_cr1 = 0;
s->tim_cr2 = 0;
s->tim_smcr = 0;
s->tim_dier = 0;
s->tim_sr = 0;
s->tim_egr = 0;
s->tim_ccmr1 = 0;
s->tim_ccmr2 = 0;
s->tim_ccer = 0;
s->tim_psc = 0;
s->tim_arr = 0;
s->tim_ccr1 = 0;
s->tim_ccr2 = 0;
s->tim_ccr3 = 0;
s->tim_ccr4 = 0;
s->tim_dcr = 0;
s->tim_dmar = 0;
s->tim_or = 0;
s->tick_offset = stm32f2xx_ns_to_ticks(s, now);
}
static uint64_t stm32f2xx_timer_read(void *opaque, hwaddr offset,
unsigned size)
{
STM32F2XXTimerState *s = opaque;
DB_PRINT("Read 0x%"HWADDR_PRIx"\n", offset);
switch (offset) {
case TIM_CR1:
return s->tim_cr1;
case TIM_CR2:
return s->tim_cr2;
case TIM_SMCR:
return s->tim_smcr;
case TIM_DIER:
return s->tim_dier;
case TIM_SR:
return s->tim_sr;
case TIM_EGR:
return s->tim_egr;
case TIM_CCMR1:
return s->tim_ccmr1;
case TIM_CCMR2:
return s->tim_ccmr2;
case TIM_CCER:
return s->tim_ccer;
case TIM_CNT:
return stm32f2xx_ns_to_ticks(s, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL)) -
s->tick_offset;
case TIM_PSC:
return s->tim_psc;
case TIM_ARR:
return s->tim_arr;
case TIM_CCR1:
return s->tim_ccr1;
case TIM_CCR2:
return s->tim_ccr2;
case TIM_CCR3:
return s->tim_ccr3;
case TIM_CCR4:
return s->tim_ccr4;
case TIM_DCR:
return s->tim_dcr;
case TIM_DMAR:
return s->tim_dmar;
case TIM_OR:
return s->tim_or;
default:
qemu_log_mask(LOG_GUEST_ERROR,
"%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, offset);
}
return 0;
}
static void stm32f2xx_timer_write(void *opaque, hwaddr offset,
uint64_t val64, unsigned size)
{
STM32F2XXTimerState *s = opaque;
uint32_t value = val64;
int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
uint32_t timer_val = 0;
DB_PRINT("Write 0x%x, 0x%"HWADDR_PRIx"\n", value, offset);
switch (offset) {
case TIM_CR1:
s->tim_cr1 = value;
return;
case TIM_CR2:
s->tim_cr2 = value;
return;
case TIM_SMCR:
s->tim_smcr = value;
return;
case TIM_DIER:
s->tim_dier = value;
return;
case TIM_SR:
/* This is set by hardware and cleared by software */
s->tim_sr &= value;
return;
case TIM_EGR:
s->tim_egr = value;
if (s->tim_egr & TIM_EGR_UG) {
timer_val = 0;
break;
}
return;
case TIM_CCMR1:
s->tim_ccmr1 = value;
return;
case TIM_CCMR2:
s->tim_ccmr2 = value;
return;
case TIM_CCER:
s->tim_ccer = value;
return;
case TIM_PSC:
timer_val = stm32f2xx_ns_to_ticks(s, now) - s->tick_offset;
s->tim_psc = value & 0xFFFF;
break;
case TIM_CNT:
timer_val = value;
break;
case TIM_ARR:
s->tim_arr = value;
stm32f2xx_timer_set_alarm(s, now);
return;
case TIM_CCR1:
s->tim_ccr1 = value;
return;
case TIM_CCR2:
s->tim_ccr2 = value;
return;
case TIM_CCR3:
s->tim_ccr3 = value;
return;
case TIM_CCR4:
s->tim_ccr4 = value;
return;
case TIM_DCR:
s->tim_dcr = value;
return;
case TIM_DMAR:
s->tim_dmar = value;
return;
case TIM_OR:
s->tim_or = value;
return;
default:
qemu_log_mask(LOG_GUEST_ERROR,
"%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, offset);
return;
}
/* This means that a register write has affected the timer in a way that
* requires a refresh of both tick_offset and the alarm.
*/
s->tick_offset = stm32f2xx_ns_to_ticks(s, now) - timer_val;
stm32f2xx_timer_set_alarm(s, now);
}
static const MemoryRegionOps stm32f2xx_timer_ops = {
.read = stm32f2xx_timer_read,
.write = stm32f2xx_timer_write,
.endianness = DEVICE_NATIVE_ENDIAN,
};
static const VMStateDescription vmstate_stm32f2xx_timer = {
.name = TYPE_STM32F2XX_TIMER,
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_INT64(tick_offset, STM32F2XXTimerState),
VMSTATE_UINT32(tim_cr1, STM32F2XXTimerState),
VMSTATE_UINT32(tim_cr2, STM32F2XXTimerState),
VMSTATE_UINT32(tim_smcr, STM32F2XXTimerState),
VMSTATE_UINT32(tim_dier, STM32F2XXTimerState),
VMSTATE_UINT32(tim_sr, STM32F2XXTimerState),
VMSTATE_UINT32(tim_egr, STM32F2XXTimerState),
VMSTATE_UINT32(tim_ccmr1, STM32F2XXTimerState),
VMSTATE_UINT32(tim_ccmr2, STM32F2XXTimerState),
VMSTATE_UINT32(tim_ccer, STM32F2XXTimerState),
VMSTATE_UINT32(tim_psc, STM32F2XXTimerState),
VMSTATE_UINT32(tim_arr, STM32F2XXTimerState),
VMSTATE_UINT32(tim_ccr1, STM32F2XXTimerState),
VMSTATE_UINT32(tim_ccr2, STM32F2XXTimerState),
VMSTATE_UINT32(tim_ccr3, STM32F2XXTimerState),
VMSTATE_UINT32(tim_ccr4, STM32F2XXTimerState),
VMSTATE_UINT32(tim_dcr, STM32F2XXTimerState),
VMSTATE_UINT32(tim_dmar, STM32F2XXTimerState),
VMSTATE_UINT32(tim_or, STM32F2XXTimerState),
VMSTATE_END_OF_LIST()
}
};
static Property stm32f2xx_timer_properties[] = {
DEFINE_PROP_UINT64("clock-frequency", struct STM32F2XXTimerState,
freq_hz, 1000000000),
DEFINE_PROP_END_OF_LIST(),
};
static void stm32f2xx_timer_init(Object *obj)
{
STM32F2XXTimerState *s = STM32F2XXTIMER(obj);
sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->irq);
memory_region_init_io(&s->iomem, obj, &stm32f2xx_timer_ops, s,
"stm32f2xx_timer", 0x400);
sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->iomem);
}
static void stm32f2xx_timer_realize(DeviceState *dev, Error **errp)
{
STM32F2XXTimerState *s = STM32F2XXTIMER(dev);
s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, stm32f2xx_timer_interrupt, s);
}
static void stm32f2xx_timer_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->reset = stm32f2xx_timer_reset;
device_class_set_props(dc, stm32f2xx_timer_properties);
dc->vmsd = &vmstate_stm32f2xx_timer;
dc->realize = stm32f2xx_timer_realize;
}
static const TypeInfo stm32f2xx_timer_info = {
.name = TYPE_STM32F2XX_TIMER,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(STM32F2XXTimerState),
.instance_init = stm32f2xx_timer_init,
.class_init = stm32f2xx_timer_class_init,
};
static void stm32f2xx_timer_register_types(void)
{
type_register_static(&stm32f2xx_timer_info);
}
type_init(stm32f2xx_timer_register_types)