From a32a22535794ed24dc32cc4232e4ba150cdfc829 Mon Sep 17 00:00:00 2001 From: Chris Wulff Date: Wed, 18 Jan 2017 23:01:44 +0100 Subject: [PATCH] nios2: Add periodic timer emulation Add the Altera timer model. Signed-off-by: Marek Vasut Cc: Chris Wulff Cc: Jeff Da Silva Cc: Ley Foon Tan Cc: Sandra Loosemore Cc: Yves Vandervennet Reviewed-by: Alexander Graf Message-Id: <20170118220146.489-6-marex@denx.de> Signed-off-by: Richard Henderson --- hw/timer/Makefile.objs | 1 + hw/timer/altera_timer.c | 237 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 238 insertions(+) create mode 100644 hw/timer/altera_timer.c diff --git a/hw/timer/Makefile.objs b/hw/timer/Makefile.objs index c1e93a3924..71994f2d88 100644 --- a/hw/timer/Makefile.objs +++ b/hw/timer/Makefile.objs @@ -18,6 +18,7 @@ common-obj-$(CONFIG_IMX) += imx_gpt.o common-obj-$(CONFIG_LM32) += lm32_timer.o common-obj-$(CONFIG_MILKYMIST) += milkymist-sysctl.o +obj-$(CONFIG_ALTERA_TIMER) += altera_timer.o obj-$(CONFIG_EXYNOS4) += exynos4210_mct.o obj-$(CONFIG_EXYNOS4) += exynos4210_pwm.o obj-$(CONFIG_EXYNOS4) += exynos4210_rtc.o diff --git a/hw/timer/altera_timer.c b/hw/timer/altera_timer.c new file mode 100644 index 0000000000..6d4862661d --- /dev/null +++ b/hw/timer/altera_timer.c @@ -0,0 +1,237 @@ +/* + * QEMU model of the Altera timer. + * + * Copyright (c) 2012 Chris Wulff + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, see + * + */ + +#include "qemu/osdep.h" +#include "qemu-common.h" +#include "qapi/error.h" + +#include "hw/sysbus.h" +#include "sysemu/sysemu.h" +#include "hw/ptimer.h" + +#define R_STATUS 0 +#define R_CONTROL 1 +#define R_PERIODL 2 +#define R_PERIODH 3 +#define R_SNAPL 4 +#define R_SNAPH 5 +#define R_MAX 6 + +#define STATUS_TO 0x0001 +#define STATUS_RUN 0x0002 + +#define CONTROL_ITO 0x0001 +#define CONTROL_CONT 0x0002 +#define CONTROL_START 0x0004 +#define CONTROL_STOP 0x0008 + +#define TYPE_ALTERA_TIMER "ALTR.timer" +#define ALTERA_TIMER(obj) \ + OBJECT_CHECK(AlteraTimer, (obj), TYPE_ALTERA_TIMER) + +typedef struct AlteraTimer { + SysBusDevice busdev; + MemoryRegion mmio; + qemu_irq irq; + uint32_t freq_hz; + QEMUBH *bh; + ptimer_state *ptimer; + uint32_t regs[R_MAX]; +} AlteraTimer; + +static int timer_irq_state(AlteraTimer *t) +{ + bool irq = (t->regs[R_STATUS] & STATUS_TO) && + (t->regs[R_CONTROL] & CONTROL_ITO); + return irq; +} + +static uint64_t timer_read(void *opaque, hwaddr addr, + unsigned int size) +{ + AlteraTimer *t = opaque; + uint64_t r = 0; + + addr >>= 2; + + switch (addr) { + case R_CONTROL: + r = t->regs[R_CONTROL] & (CONTROL_ITO | CONTROL_CONT); + break; + + default: + if (addr < ARRAY_SIZE(t->regs)) { + r = t->regs[addr]; + } + break; + } + + return r; +} + +static void timer_write(void *opaque, hwaddr addr, + uint64_t value, unsigned int size) +{ + AlteraTimer *t = opaque; + uint64_t tvalue; + uint32_t count = 0; + int irqState = timer_irq_state(t); + + addr >>= 2; + + switch (addr) { + case R_STATUS: + /* The timeout bit is cleared by writing the status register. */ + t->regs[R_STATUS] &= ~STATUS_TO; + break; + + case R_CONTROL: + t->regs[R_CONTROL] = value & (CONTROL_ITO | CONTROL_CONT); + if ((value & CONTROL_START) && + !(t->regs[R_STATUS] & STATUS_RUN)) { + ptimer_run(t->ptimer, 1); + t->regs[R_STATUS] |= STATUS_RUN; + } + if ((value & CONTROL_STOP) && (t->regs[R_STATUS] & STATUS_RUN)) { + ptimer_stop(t->ptimer); + t->regs[R_STATUS] &= ~STATUS_RUN; + } + break; + + case R_PERIODL: + case R_PERIODH: + t->regs[addr] = value & 0xFFFF; + if (t->regs[R_STATUS] & STATUS_RUN) { + ptimer_stop(t->ptimer); + t->regs[R_STATUS] &= ~STATUS_RUN; + } + tvalue = (t->regs[R_PERIODH] << 16) | t->regs[R_PERIODL]; + ptimer_set_limit(t->ptimer, tvalue + 1, 1); + break; + + case R_SNAPL: + case R_SNAPH: + count = ptimer_get_count(t->ptimer); + t->regs[R_SNAPL] = count & 0xFFFF; + t->regs[R_SNAPH] = count >> 16; + break; + + default: + break; + } + + if (irqState != timer_irq_state(t)) { + qemu_set_irq(t->irq, timer_irq_state(t)); + } +} + +static const MemoryRegionOps timer_ops = { + .read = timer_read, + .write = timer_write, + .endianness = DEVICE_NATIVE_ENDIAN, + .valid = { + .min_access_size = 1, + .max_access_size = 4 + } +}; + +static void timer_hit(void *opaque) +{ + AlteraTimer *t = opaque; + const uint64_t tvalue = (t->regs[R_PERIODH] << 16) | t->regs[R_PERIODL]; + + t->regs[R_STATUS] |= STATUS_TO; + + ptimer_set_limit(t->ptimer, tvalue + 1, 1); + + if (!(t->regs[R_CONTROL] & CONTROL_CONT)) { + t->regs[R_STATUS] &= ~STATUS_RUN; + ptimer_set_count(t->ptimer, tvalue); + } else { + ptimer_run(t->ptimer, 1); + } + + qemu_set_irq(t->irq, timer_irq_state(t)); +} + +static void altera_timer_realize(DeviceState *dev, Error **errp) +{ + AlteraTimer *t = ALTERA_TIMER(dev); + SysBusDevice *sbd = SYS_BUS_DEVICE(dev); + + if (t->freq_hz == 0) { + error_setg(errp, "\"clock-frequency\" property must be provided."); + return; + } + + t->bh = qemu_bh_new(timer_hit, t); + t->ptimer = ptimer_init(t->bh, PTIMER_POLICY_DEFAULT); + ptimer_set_freq(t->ptimer, t->freq_hz); + + memory_region_init_io(&t->mmio, OBJECT(t), &timer_ops, t, + TYPE_ALTERA_TIMER, R_MAX * sizeof(uint32_t)); + sysbus_init_mmio(sbd, &t->mmio); +} + +static void altera_timer_init(Object *obj) +{ + AlteraTimer *t = ALTERA_TIMER(obj); + SysBusDevice *sbd = SYS_BUS_DEVICE(obj); + + sysbus_init_irq(sbd, &t->irq); +} + +static void altera_timer_reset(DeviceState *dev) +{ + AlteraTimer *t = ALTERA_TIMER(dev); + + ptimer_stop(t->ptimer); + ptimer_set_limit(t->ptimer, 0xffffffff, 1); + memset(t->regs, 0, ARRAY_SIZE(t->regs)); +} + +static Property altera_timer_properties[] = { + DEFINE_PROP_UINT32("clock-frequency", AlteraTimer, freq_hz, 0), + DEFINE_PROP_END_OF_LIST(), +}; + +static void altera_timer_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->realize = altera_timer_realize; + dc->props = altera_timer_properties; + dc->reset = altera_timer_reset; +} + +static const TypeInfo altera_timer_info = { + .name = TYPE_ALTERA_TIMER, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(AlteraTimer), + .instance_init = altera_timer_init, + .class_init = altera_timer_class_init, +}; + +static void altera_timer_register(void) +{ + type_register_static(&altera_timer_info); +} + +type_init(altera_timer_register)