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authorChris Wulff <crwulff@gmail.com>2017-01-18 23:01:44 +0100
committerRichard Henderson <rth@twiddle.net>2017-01-24 13:10:35 -0800
commita32a22535794ed24dc32cc4232e4ba150cdfc829 (patch)
tree5de43ed99d32b67b5a6c4bf0b6f340b9fc430fa3
parentd2fe4ec19dd3060b12a04370300e49e4b6e519b5 (diff)
nios2: Add periodic timer emulation
Add the Altera timer model. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Chris Wulff <crwulff@gmail.com> Cc: Jeff Da Silva <jdasilva@altera.com> Cc: Ley Foon Tan <lftan@altera.com> Cc: Sandra Loosemore <sandra@codesourcery.com> Cc: Yves Vandervennet <yvanderv@altera.com> Reviewed-by: Alexander Graf <agraf@suse.de> Message-Id: <20170118220146.489-6-marex@denx.de> Signed-off-by: Richard Henderson <rth@twiddle.net>
-rw-r--r--hw/timer/Makefile.objs1
-rw-r--r--hw/timer/altera_timer.c237
2 files changed, 238 insertions, 0 deletions
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 <crwulff@gmail.com>
+ *
+ * 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
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+#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)