On Wed, Jun 9, 2021 at 5:57 PM Paolo Bonzini <pbonz...@redhat.com> wrote:
>
> On 09/06/21 01:48, Alistair Francis wrote:
> > Add support for the Ibex timer. This is used with the RISC-V
> > mtime/mtimecmp similar to the SiFive CLINT.
> >
> > We currently don't support changing the prescale or the timervalue.
> >
> > Signed-off-by: Alistair Francis <alistair.fran...@wdc.com>
>
> Any chance this could have a qtest? It would also be nice if the CPU
Yep, do you have a good example of what the qtest should look like?
> had qemu_irqs for MEIP/MTIP/SEIP (possibly MSIP too but that one is
> bidirectional), so that instead of riscv_cpu_update_mip you can just
> connect to a GPIO pin of the CPU and do qemu_set_irq. It could also be
> used by the qtests via irq_intercept_in.
Yeah the riscv_cpu_update_mip() is not ideal. As it is what we
currently also use for the CLINT I don't want to fix it up here. In
the future I'll work on changing riscv_cpu_update_mip in all the
RISC-V timers to use GPIO lines instead.
Alistair
>
> Paolo
>
> > ---
> > include/hw/timer/ibex_timer.h | 52 ++++++
> > hw/timer/ibex_timer.c | 305 ++++++++++++++++++++++++++++++++++
> > MAINTAINERS | 6 +-
> > hw/timer/meson.build | 1 +
> > 4 files changed, 360 insertions(+), 4 deletions(-)
> > create mode 100644 include/hw/timer/ibex_timer.h
> > create mode 100644 hw/timer/ibex_timer.c
> >
> > diff --git a/include/hw/timer/ibex_timer.h b/include/hw/timer/ibex_timer.h
> > new file mode 100644
> > index 0000000000..6a43537003
> > --- /dev/null
> > +++ b/include/hw/timer/ibex_timer.h
> > @@ -0,0 +1,52 @@
> > +/*
> > + * QEMU lowRISC Ibex Timer device
> > + *
> > + * Copyright (c) 2021 Western Digital
> > + *
> > + * 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.
> > + */
> > +
> > +#ifndef HW_IBEX_TIMER_H
> > +#define HW_IBEX_TIMER_H
> > +
> > +#include "hw/sysbus.h"
> > +
> > +#define TYPE_IBEX_TIMER "ibex-timer"
> > +OBJECT_DECLARE_SIMPLE_TYPE(IbexTimerState, IBEX_TIMER)
> > +
> > +struct IbexTimerState {
> > + /* <private> */
> > + SysBusDevice parent_obj;
> > +
> > + /* <public> */
> > + MemoryRegion mmio;
> > +
> > + uint32_t timer_ctrl;
> > + uint32_t timer_cfg0;
> > + uint32_t timer_compare_lower0;
> > + uint32_t timer_compare_upper0;
> > + uint32_t timer_intr_enable;
> > + uint32_t timer_intr_state;
> > + uint32_t timer_intr_test;
> > +
> > + uint32_t timebase_freq;
> > +
> > + qemu_irq irq;
> > +};
> > +#endif /* HW_IBEX_TIMER_H */
> > diff --git a/hw/timer/ibex_timer.c b/hw/timer/ibex_timer.c
> > new file mode 100644
> > index 0000000000..4d55eb5088
> > --- /dev/null
> > +++ b/hw/timer/ibex_timer.c
> > @@ -0,0 +1,305 @@
> > +/*
> > + * QEMU lowRISC Ibex Timer device
> > + *
> > + * Copyright (c) 2021 Western Digital
> > + *
> > + * For details check the documentation here:
> > + * https://docs.opentitan.org/hw/ip/rv_timer/doc/
> > + *
> > + * 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 "qemu/log.h"
> > +#include "qemu/timer.h"
> > +#include "hw/timer/ibex_timer.h"
> > +#include "hw/irq.h"
> > +#include "hw/qdev-properties.h"
> > +#include "target/riscv/cpu.h"
> > +#include "migration/vmstate.h"
> > +
> > +REG32(CTRL, 0x00)
> > + FIELD(CTRL, ACTIVE, 0, 1)
> > +REG32(CFG0, 0x100)
> > + FIELD(CFG0, PRESCALE, 0, 12)
> > + FIELD(CFG0, STEP, 16, 8)
> > +REG32(LOWER0, 0x104)
> > +REG32(UPPER0, 0x108)
> > +REG32(COMPARE_LOWER0, 0x10C)
> > +REG32(COMPARE_UPPER0, 0x110)
> > +REG32(INTR_ENABLE, 0x114)
> > + FIELD(INTR_ENABLE, IE_0, 0, 1)
> > +REG32(INTR_STATE, 0x118)
> > + FIELD(INTR_STATE, IS_0, 0, 1)
> > +REG32(INTR_TEST, 0x11C)
> > + FIELD(INTR_TEST, T_0, 0, 1)
> > +
> > +static uint64_t cpu_riscv_read_rtc(uint32_t timebase_freq)
> > +{
> > + return muldiv64(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL),
> > + timebase_freq, NANOSECONDS_PER_SECOND);
> > +}
> > +
> > +static void ibex_timer_update_irqs(IbexTimerState *s)
> > +{
> > + CPUState *cs = qemu_get_cpu(0);
> > + RISCVCPU *cpu = RISCV_CPU(cs);
> > + uint64_t value = s->timer_compare_lower0 |
> > + ((uint64_t)s->timer_compare_upper0 << 32);
> > + uint64_t next, diff;
> > + uint64_t now = cpu_riscv_read_rtc(s->timebase_freq);
> > +
> > + if (!(s->timer_ctrl & R_CTRL_ACTIVE_MASK)) {
> > + /* Timer isn't active */
> > + return;
> > + }
> > +
> > + /* Update the CPUs mtimecmp */
> > + cpu->env.timecmp = value;
> > +
> > + if (cpu->env.timecmp <= now) {
> > + /*
> > + * If the mtimecmp was in the past raise the interrupt now.
> > + */
> > + riscv_cpu_update_mip(cpu, MIP_MTIP, BOOL_TO_MASK(1));
> > + if (s->timer_intr_enable & R_INTR_ENABLE_IE_0_MASK) {
> > + s->timer_intr_state |= R_INTR_STATE_IS_0_MASK;
> > + qemu_set_irq(s->irq, true);
> > + }
> > + return;
> > + }
> > +
> > + /* Setup a timer to trigger the interrupt in the future */
> > + riscv_cpu_update_mip(cpu, MIP_MTIP, BOOL_TO_MASK(0));
> > + qemu_set_irq(s->irq, false);
> > +
> > + diff = cpu->env.timecmp - now;
> > + next = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
> > + muldiv64(diff,
> > + NANOSECONDS_PER_SECOND,
> > + s->timebase_freq);
> > +
> > + if (next < qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL)) {
> > + /* We overflowed the timer, just set it as large as we can */
> > + timer_mod(cpu->env.timer, 0x07FFFFFFFFFFFFFF);
> > + } else {
> > + timer_mod(cpu->env.timer, next);
> > + }
> > +}
> > +
> > +static void ibex_timer_cb(void *opaque)
> > +{
> > + IbexTimerState *s = opaque;
> > + CPUState *cs = qemu_get_cpu(0);
> > + RISCVCPU *cpu = RISCV_CPU(cs);
> > +
> > + riscv_cpu_update_mip(cpu, MIP_MTIP, BOOL_TO_MASK(1));
> > + if (s->timer_intr_enable & R_INTR_ENABLE_IE_0_MASK) {
> > + s->timer_intr_state |= R_INTR_STATE_IS_0_MASK;
> > + qemu_set_irq(s->irq, true);
> > + }
> > +}
> > +
> > +static void ibex_timer_reset(DeviceState *dev)
> > +{
> > + IbexTimerState *s = IBEX_TIMER(dev);
> > +
> > + CPUState *cpu = qemu_get_cpu(0);
> > + CPURISCVState *env = cpu->env_ptr;
> > + env->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
> > + &ibex_timer_cb, s);
> > + env->timecmp = 0;
> > +
> > + s->timer_ctrl = 0x00000000;
> > + s->timer_cfg0 = 0x00010000;
> > + s->timer_compare_lower0 = 0xFFFFFFFF;
> > + s->timer_compare_upper0 = 0xFFFFFFFF;
> > + s->timer_intr_enable = 0x00000000;
> > + s->timer_intr_state = 0x00000000;
> > + s->timer_intr_test = 0x00000000;
> > +
> > + ibex_timer_update_irqs(s);
> > +}
> > +
> > +static uint64_t ibex_timer_read(void *opaque, hwaddr addr,
> > + unsigned int size)
> > +{
> > + IbexTimerState *s = opaque;
> > + uint64_t now = cpu_riscv_read_rtc(s->timebase_freq);
> > + uint64_t retvalue = 0;
> > +
> > + switch (addr >> 2) {
> > + case R_CTRL:
> > + retvalue = s->timer_ctrl;
> > + break;
> > + case R_CFG0:
> > + retvalue = s->timer_cfg0;
> > + break;
> > + case R_LOWER0:
> > + retvalue = now;
> > + break;
> > + case R_UPPER0:
> > + retvalue = now >> 32;
> > + break;
> > + case R_COMPARE_LOWER0:
> > + retvalue = s->timer_compare_lower0;
> > + break;
> > + case R_COMPARE_UPPER0:
> > + retvalue = s->timer_compare_upper0;
> > + break;
> > + case R_INTR_ENABLE:
> > + retvalue = s->timer_intr_enable;
> > + break;
> > + case R_INTR_STATE:
> > + retvalue = s->timer_intr_state;
> > + break;
> > + case R_INTR_TEST:
> > + retvalue = s->timer_intr_test;
> > + break;
> > + default:
> > + qemu_log_mask(LOG_GUEST_ERROR,
> > + "%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, addr);
> > + return 0;
> > + }
> > +
> > + return retvalue;
> > +}
> > +
> > +static void ibex_timer_write(void *opaque, hwaddr addr,
> > + uint64_t val64, unsigned int size)
> > +{
> > + IbexTimerState *s = opaque;
> > + uint32_t val = val64;
> > +
> > + switch (addr >> 2) {
> > + case R_CTRL:
> > + s->timer_ctrl = val;
> > + break;
> > + case R_CFG0:
> > + qemu_log_mask(LOG_UNIMP, "Changing prescale or step not
> > supported");
> > + s->timer_cfg0 = val;
> > + break;
> > + case R_LOWER0:
> > + qemu_log_mask(LOG_UNIMP, "Changing timer value is not supported");
> > + break;
> > + case R_UPPER0:
> > + qemu_log_mask(LOG_UNIMP, "Changing timer value is not supported");
> > + break;
> > + case R_COMPARE_LOWER0:
> > + s->timer_compare_lower0 = val;
> > + ibex_timer_update_irqs(s);
> > + break;
> > + case R_COMPARE_UPPER0:
> > + s->timer_compare_upper0 = val;
> > + ibex_timer_update_irqs(s);
> > + break;
> > + case R_INTR_ENABLE:
> > + s->timer_intr_enable = val;
> > + break;
> > + case R_INTR_STATE:
> > + /* Write 1 to clear */
> > + s->timer_intr_state &= ~val;
> > + break;
> > + case R_INTR_TEST:
> > + s->timer_intr_test = val;
> > + if (s->timer_intr_enable &
> > + s->timer_intr_test &
> > + R_INTR_ENABLE_IE_0_MASK) {
> > + s->timer_intr_state |= R_INTR_STATE_IS_0_MASK;
> > + qemu_set_irq(s->irq, true);
> > + }
> > + break;
> > + default:
> > + qemu_log_mask(LOG_GUEST_ERROR,
> > + "%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, addr);
> > + }
> > +}
> > +
> > +static const MemoryRegionOps ibex_timer_ops = {
> > + .read = ibex_timer_read,
> > + .write = ibex_timer_write,
> > + .endianness = DEVICE_NATIVE_ENDIAN,
> > + .impl.min_access_size = 4,
> > + .impl.max_access_size = 4,
> > +};
> > +
> > +static int ibex_timer_post_load(void *opaque, int version_id)
> > +{
> > + IbexTimerState *s = opaque;
> > +
> > + ibex_timer_update_irqs(s);
> > + return 0;
> > +}
> > +
> > +static const VMStateDescription vmstate_ibex_timer = {
> > + .name = TYPE_IBEX_TIMER,
> > + .version_id = 1,
> > + .minimum_version_id = 1,
> > + .post_load = ibex_timer_post_load,
> > + .fields = (VMStateField[]) {
> > + VMSTATE_UINT32(timer_ctrl, IbexTimerState),
> > + VMSTATE_UINT32(timer_cfg0, IbexTimerState),
> > + VMSTATE_UINT32(timer_compare_lower0, IbexTimerState),
> > + VMSTATE_UINT32(timer_compare_upper0, IbexTimerState),
> > + VMSTATE_UINT32(timer_intr_enable, IbexTimerState),
> > + VMSTATE_UINT32(timer_intr_state, IbexTimerState),
> > + VMSTATE_UINT32(timer_intr_test, IbexTimerState),
> > + VMSTATE_END_OF_LIST()
> > + }
> > +};
> > +
> > +static Property ibex_timer_properties[] = {
> > + DEFINE_PROP_UINT32("timebase-freq", IbexTimerState, timebase_freq,
> > 10000),
> > + DEFINE_PROP_END_OF_LIST(),
> > +};
> > +
> > +static void ibex_timer_init(Object *obj)
> > +{
> > + IbexTimerState *s = IBEX_TIMER(obj);
> > +
> > + sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->irq);
> > +
> > + memory_region_init_io(&s->mmio, obj, &ibex_timer_ops, s,
> > + TYPE_IBEX_TIMER, 0x400);
> > + sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio);
> > +}
> > +
> > +static void ibex_timer_class_init(ObjectClass *klass, void *data)
> > +{
> > + DeviceClass *dc = DEVICE_CLASS(klass);
> > +
> > + dc->reset = ibex_timer_reset;
> > + dc->vmsd = &vmstate_ibex_timer;
> > + device_class_set_props(dc, ibex_timer_properties);
> > +}
> > +
> > +static const TypeInfo ibex_timer_info = {
> > + .name = TYPE_IBEX_TIMER,
> > + .parent = TYPE_SYS_BUS_DEVICE,
> > + .instance_size = sizeof(IbexTimerState),
> > + .instance_init = ibex_timer_init,
> > + .class_init = ibex_timer_class_init,
> > +};
> > +
> > +static void ibex_timer_register_types(void)
> > +{
> > + type_register_static(&ibex_timer_info);
> > +}
> > +
> > +type_init(ibex_timer_register_types)
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 7d9cd29042..b661c9c14e 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -1363,11 +1363,9 @@ M: Alistair Francis <alistair.fran...@wdc.com>
> > L: qemu-ri...@nongnu.org
> > S: Supported
> > F: hw/riscv/opentitan.c
> > -F: hw/char/ibex_uart.c
> > -F: hw/intc/ibex_plic.c
> > +F: hw/*/ibex_*.c
> > F: include/hw/riscv/opentitan.h
> > -F: include/hw/char/ibex_uart.h
> > -F: include/hw/intc/ibex_plic.h
> > +F: include/hw/*/ibex_*.h
> >
> > Microchip PolarFire SoC Icicle Kit
> > M: Bin Meng <bin.m...@windriver.com>
> > diff --git a/hw/timer/meson.build b/hw/timer/meson.build
> > index 157f540ecd..1aa3cd2284 100644
> > --- a/hw/timer/meson.build
> > +++ b/hw/timer/meson.build
> > @@ -33,5 +33,6 @@ softmmu_ss.add(when: 'CONFIG_SSE_COUNTER', if_true:
> > files('sse-counter.c'))
> > softmmu_ss.add(when: 'CONFIG_SSE_TIMER', if_true: files('sse-timer.c'))
> > softmmu_ss.add(when: 'CONFIG_STM32F2XX_TIMER', if_true:
> > files('stm32f2xx_timer.c'))
> > softmmu_ss.add(when: 'CONFIG_XILINX', if_true: files('xilinx_timer.c'))
> > +specific_ss.add(when: 'CONFIG_IBEX', if_true: files('ibex_timer.c'))
> >
> > specific_ss.add(when: 'CONFIG_AVR_TIMER16', if_true:
> > files('avr_timer16.c'))
> >
>
