diff options
Diffstat (limited to 'hw/intc/sifive_clint.c')
| -rw-r--r-- | hw/intc/sifive_clint.c | 266 |
1 files changed, 266 insertions, 0 deletions
diff --git a/hw/intc/sifive_clint.c b/hw/intc/sifive_clint.c new file mode 100644 index 0000000..0f41e5e --- /dev/null +++ b/hw/intc/sifive_clint.c @@ -0,0 +1,266 @@ +/* + * SiFive CLINT (Core Local Interruptor) + * + * Copyright (c) 2016-2017 Sagar Karandikar, sagark@eecs.berkeley.edu + * Copyright (c) 2017 SiFive, Inc. + * + * This provides real-time clock, timer and interprocessor interrupts. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2 or later, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include "qemu/osdep.h" +#include "qapi/error.h" +#include "qemu/error-report.h" +#include "qemu/module.h" +#include "hw/sysbus.h" +#include "target/riscv/cpu.h" +#include "hw/qdev-properties.h" +#include "hw/intc/sifive_clint.h" +#include "qemu/timer.h" + +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); +} + +/* + * Called when timecmp is written to update the QEMU timer or immediately + * trigger timer interrupt if mtimecmp <= current timer value. + */ +static void sifive_clint_write_timecmp(RISCVCPU *cpu, uint64_t value, + uint32_t timebase_freq) +{ + uint64_t next; + uint64_t diff; + + uint64_t rtc_r = cpu_riscv_read_rtc(timebase_freq); + + cpu->env.timecmp = value; + if (cpu->env.timecmp <= rtc_r) { + /* if we're setting an MTIMECMP value in the "past", + immediately raise the timer interrupt */ + riscv_cpu_update_mip(cpu, MIP_MTIP, BOOL_TO_MASK(1)); + return; + } + + /* otherwise, set up the future timer interrupt */ + riscv_cpu_update_mip(cpu, MIP_MTIP, BOOL_TO_MASK(0)); + diff = cpu->env.timecmp - rtc_r; + /* back to ns (note args switched in muldiv64) */ + next = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + + muldiv64(diff, NANOSECONDS_PER_SECOND, timebase_freq); + timer_mod(cpu->env.timer, next); +} + +/* + * Callback used when the timer set using timer_mod expires. + * Should raise the timer interrupt line + */ +static void sifive_clint_timer_cb(void *opaque) +{ + RISCVCPU *cpu = opaque; + riscv_cpu_update_mip(cpu, MIP_MTIP, BOOL_TO_MASK(1)); +} + +/* CPU wants to read rtc or timecmp register */ +static uint64_t sifive_clint_read(void *opaque, hwaddr addr, unsigned size) +{ + SiFiveCLINTState *clint = opaque; + if (addr >= clint->sip_base && + addr < clint->sip_base + (clint->num_harts << 2)) { + size_t hartid = clint->hartid_base + ((addr - clint->sip_base) >> 2); + CPUState *cpu = qemu_get_cpu(hartid); + CPURISCVState *env = cpu ? cpu->env_ptr : NULL; + if (!env) { + error_report("clint: invalid timecmp hartid: %zu", hartid); + } else if ((addr & 0x3) == 0) { + return (env->mip & MIP_MSIP) > 0; + } else { + error_report("clint: invalid read: %08x", (uint32_t)addr); + return 0; + } + } else if (addr >= clint->timecmp_base && + addr < clint->timecmp_base + (clint->num_harts << 3)) { + size_t hartid = clint->hartid_base + + ((addr - clint->timecmp_base) >> 3); + CPUState *cpu = qemu_get_cpu(hartid); + CPURISCVState *env = cpu ? cpu->env_ptr : NULL; + if (!env) { + error_report("clint: invalid timecmp hartid: %zu", hartid); + } else if ((addr & 0x7) == 0) { + /* timecmp_lo */ + uint64_t timecmp = env->timecmp; + return timecmp & 0xFFFFFFFF; + } else if ((addr & 0x7) == 4) { + /* timecmp_hi */ + uint64_t timecmp = env->timecmp; + return (timecmp >> 32) & 0xFFFFFFFF; + } else { + error_report("clint: invalid read: %08x", (uint32_t)addr); + return 0; + } + } else if (addr == clint->time_base) { + /* time_lo */ + return cpu_riscv_read_rtc(clint->timebase_freq) & 0xFFFFFFFF; + } else if (addr == clint->time_base + 4) { + /* time_hi */ + return (cpu_riscv_read_rtc(clint->timebase_freq) >> 32) & 0xFFFFFFFF; + } + + error_report("clint: invalid read: %08x", (uint32_t)addr); + return 0; +} + +/* CPU wrote to rtc or timecmp register */ +static void sifive_clint_write(void *opaque, hwaddr addr, uint64_t value, + unsigned size) +{ + SiFiveCLINTState *clint = opaque; + + if (addr >= clint->sip_base && + addr < clint->sip_base + (clint->num_harts << 2)) { + size_t hartid = clint->hartid_base + ((addr - clint->sip_base) >> 2); + CPUState *cpu = qemu_get_cpu(hartid); + CPURISCVState *env = cpu ? cpu->env_ptr : NULL; + if (!env) { + error_report("clint: invalid timecmp hartid: %zu", hartid); + } else if ((addr & 0x3) == 0) { + riscv_cpu_update_mip(RISCV_CPU(cpu), MIP_MSIP, BOOL_TO_MASK(value)); + } else { + error_report("clint: invalid sip write: %08x", (uint32_t)addr); + } + return; + } else if (addr >= clint->timecmp_base && + addr < clint->timecmp_base + (clint->num_harts << 3)) { + size_t hartid = clint->hartid_base + + ((addr - clint->timecmp_base) >> 3); + CPUState *cpu = qemu_get_cpu(hartid); + CPURISCVState *env = cpu ? cpu->env_ptr : NULL; + if (!env) { + error_report("clint: invalid timecmp hartid: %zu", hartid); + } else if ((addr & 0x7) == 0) { + /* timecmp_lo */ + uint64_t timecmp_hi = env->timecmp >> 32; + sifive_clint_write_timecmp(RISCV_CPU(cpu), + timecmp_hi << 32 | (value & 0xFFFFFFFF), clint->timebase_freq); + return; + } else if ((addr & 0x7) == 4) { + /* timecmp_hi */ + uint64_t timecmp_lo = env->timecmp; + sifive_clint_write_timecmp(RISCV_CPU(cpu), + value << 32 | (timecmp_lo & 0xFFFFFFFF), clint->timebase_freq); + } else { + error_report("clint: invalid timecmp write: %08x", (uint32_t)addr); + } + return; + } else if (addr == clint->time_base) { + /* time_lo */ + error_report("clint: time_lo write not implemented"); + return; + } else if (addr == clint->time_base + 4) { + /* time_hi */ + error_report("clint: time_hi write not implemented"); + return; + } + + error_report("clint: invalid write: %08x", (uint32_t)addr); +} + +static const MemoryRegionOps sifive_clint_ops = { + .read = sifive_clint_read, + .write = sifive_clint_write, + .endianness = DEVICE_LITTLE_ENDIAN, + .valid = { + .min_access_size = 4, + .max_access_size = 8 + } +}; + +static Property sifive_clint_properties[] = { + DEFINE_PROP_UINT32("hartid-base", SiFiveCLINTState, hartid_base, 0), + DEFINE_PROP_UINT32("num-harts", SiFiveCLINTState, num_harts, 0), + DEFINE_PROP_UINT32("sip-base", SiFiveCLINTState, sip_base, 0), + DEFINE_PROP_UINT32("timecmp-base", SiFiveCLINTState, timecmp_base, 0), + DEFINE_PROP_UINT32("time-base", SiFiveCLINTState, time_base, 0), + DEFINE_PROP_UINT32("aperture-size", SiFiveCLINTState, aperture_size, 0), + DEFINE_PROP_UINT32("timebase-freq", SiFiveCLINTState, timebase_freq, 0), + DEFINE_PROP_END_OF_LIST(), +}; + +static void sifive_clint_realize(DeviceState *dev, Error **errp) +{ + SiFiveCLINTState *s = SIFIVE_CLINT(dev); + memory_region_init_io(&s->mmio, OBJECT(dev), &sifive_clint_ops, s, + TYPE_SIFIVE_CLINT, s->aperture_size); + sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->mmio); +} + +static void sifive_clint_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + dc->realize = sifive_clint_realize; + device_class_set_props(dc, sifive_clint_properties); +} + +static const TypeInfo sifive_clint_info = { + .name = TYPE_SIFIVE_CLINT, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(SiFiveCLINTState), + .class_init = sifive_clint_class_init, +}; + +static void sifive_clint_register_types(void) +{ + type_register_static(&sifive_clint_info); +} + +type_init(sifive_clint_register_types) + + +/* + * Create CLINT device. + */ +DeviceState *sifive_clint_create(hwaddr addr, hwaddr size, + uint32_t hartid_base, uint32_t num_harts, uint32_t sip_base, + uint32_t timecmp_base, uint32_t time_base, uint32_t timebase_freq, + bool provide_rdtime) +{ + int i; + for (i = 0; i < num_harts; i++) { + CPUState *cpu = qemu_get_cpu(hartid_base + i); + CPURISCVState *env = cpu ? cpu->env_ptr : NULL; + if (!env) { + continue; + } + if (provide_rdtime) { + riscv_cpu_set_rdtime_fn(env, cpu_riscv_read_rtc, timebase_freq); + } + env->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, + &sifive_clint_timer_cb, cpu); + env->timecmp = 0; + } + + DeviceState *dev = qdev_new(TYPE_SIFIVE_CLINT); + qdev_prop_set_uint32(dev, "hartid-base", hartid_base); + qdev_prop_set_uint32(dev, "num-harts", num_harts); + qdev_prop_set_uint32(dev, "sip-base", sip_base); + qdev_prop_set_uint32(dev, "timecmp-base", timecmp_base); + qdev_prop_set_uint32(dev, "time-base", time_base); + qdev_prop_set_uint32(dev, "aperture-size", size); + qdev_prop_set_uint32(dev, "timebase-freq", timebase_freq); + sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal); + sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, addr); + return dev; +} |