Message ID | 27436e8864997f4d67d9562f1db41da2db05f4cf.1588878756.git.alistair.francis@wdc.com |
---|---|
State | New |
Headers | show |
Series | RISC-V Add the OpenTitan Machine | expand |
On 5/7/20 9:13 PM, Alistair Francis wrote: > The Ibex core contains a PLIC that although similar to the RISC-V spec > is not RISC-V spec compliant. > > This patch implements a Ibex PLIC in a somewhat generic way. > > As the current RISC-V PLIC needs tidying up, my hope is that as the Ibex > PLIC move towards spec compliance this PLIC implementation can be > updated until it can replace the current PLIC. > > Signed-off-by: Alistair Francis <alistair.francis@wdc.com> > --- > MAINTAINERS | 2 + > hw/intc/Makefile.objs | 1 + > hw/intc/ibex_plic.c | 261 ++++++++++++++++++++++++++++++++++++ > include/hw/intc/ibex_plic.h | 63 +++++++++ > 4 files changed, 327 insertions(+) > create mode 100644 hw/intc/ibex_plic.c > create mode 100644 include/hw/intc/ibex_plic.h > > diff --git a/MAINTAINERS b/MAINTAINERS > index d3d47564ce..f8c3cf6182 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -1237,8 +1237,10 @@ L: qemu-riscv@nongnu.org > S: Supported > F: hw/riscv/opentitan.c > F: hw/char/ibex_uart.c > +F: hw/intc/ibex_plic.c > F: include/hw/riscv/opentitan.h > F: include/hw/char/ibex_uart.h > +F: include/hw/intc/ibex_plic.h > > > SH4 Machines > diff --git a/hw/intc/Makefile.objs b/hw/intc/Makefile.objs > index f726d87532..a61e6728fe 100644 > --- a/hw/intc/Makefile.objs > +++ b/hw/intc/Makefile.objs > @@ -49,3 +49,4 @@ obj-$(CONFIG_ARM_GIC) += arm_gicv3_cpuif.o > obj-$(CONFIG_MIPS_CPS) += mips_gic.o > obj-$(CONFIG_NIOS2) += nios2_iic.o > obj-$(CONFIG_OMPIC) += ompic.o > +obj-$(CONFIG_IBEX) += ibex_plic.o > diff --git a/hw/intc/ibex_plic.c b/hw/intc/ibex_plic.c > new file mode 100644 > index 0000000000..35c52d9d16 > --- /dev/null > +++ b/hw/intc/ibex_plic.c > @@ -0,0 +1,261 @@ > +/* > + * QEMU RISC-V lowRISC Ibex PLIC > + * > + * Copyright (c) 2020 Western Digital > + * > + * Documentation avaliable: https://docs.opentitan.org/hw/ip/rv_plic/doc/ > + * > + * 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 "qemu/log.h" > +#include "hw/qdev-properties.h" > +#include "hw/core/cpu.h" > +#include "hw/boards.h" > +#include "hw/pci/msi.h" > +#include "target/riscv/cpu_bits.h" > +#include "target/riscv/cpu.h" > +#include "hw/intc/ibex_plic.h" > + > +static bool addr_between(uint32_t addr, uint32_t base, uint32_t num) > +{ > + uint32_t end = base + (num * 0x04); > + > + if (addr >= base && addr < end) { > + return true; > + } > + > + return false; > +} > + > +static void ibex_plic_irqs_set_pending(IbexPlicState *s, int irq, bool level) > +{ > + int pending_num = irq / 32; > + > + s->pending[pending_num] |= level << (irq % 32); > +} > + > +static bool ibex_plic_irqs_pending(IbexPlicState *s, uint32_t context) > +{ > + int i; > + > + for (i = 0; i < s->pending_num; i++) { > + uint32_t irq_num = ctz64(s->pending[i]) + (i * 32); > + > + if (!(s->pending[i] & s->enable[i])) { > + /* No pending and enabled IRQ */ > + continue; > + } > + > + if (s->priority[irq_num] > s->threshold) { > + if (!s->claim) { > + s->claim = irq_num; > + } > + return true; > + } > + } > + > + return 0; return 'false'. > +} > + > +static void ibex_plic_update(IbexPlicState *s) > +{ > + CPUState *cpu; > + int level, i; > + > + for (i = 0; i < s->num_cpus; i++) { > + cpu = qemu_get_cpu(i); > + > + if (!cpu) { > + continue; > + } > + > + level = ibex_plic_irqs_pending(s, 0); > + > + riscv_cpu_update_mip(RISCV_CPU(cpu), MIP_MEIP, BOOL_TO_MASK(level)); > + } > +} > + > +static void ibex_plic_reset(DeviceState *dev) > +{ > + IbexPlicState *s = IBEX_PLIC(dev); > + > + s->threshold = 0x00000000; > + s->claim = 0x00000000; I haven't check the datasheet reset values, for the rest: Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> > +} > + > +static uint64_t ibex_plic_read(void *opaque, hwaddr addr, > + unsigned int size) > +{ > + IbexPlicState *s = opaque; > + int offset; > + uint32_t ret = 0; > + > + if (addr_between(addr, s->pending_base, s->pending_num)) { > + offset = (addr - s->pending_base) / 4; > + ret = s->pending[offset]; > + } else if (addr_between(addr, s->source_base, s->source_num)) { > + qemu_log_mask(LOG_UNIMP, > + "%s: Interrupt source mode not supported\n", __func__); > + } else if (addr_between(addr, s->priority_base, s->priority_num)) { > + offset = (addr - s->priority_base) / 4; > + ret = s->priority[offset]; > + } else if (addr_between(addr, s->enable_base, s->enable_num)) { > + offset = (addr - s->enable_base) / 4; > + ret = s->enable[offset]; > + } else if (addr_between(addr, s->threshold_base, 1)) { > + ret = s->threshold; > + } else if (addr_between(addr, s->claim_base, 1)) { > + int pending_num = s->claim / 32; > + s->pending[pending_num] &= ~(1 << (s->claim % 32)); > + > + ret = s->claim; > + } > + > + return ret; > +} > + > +static void ibex_plic_write(void *opaque, hwaddr addr, > + uint64_t value, unsigned int size) > +{ > + IbexPlicState *s = opaque; > + > + if (addr_between(addr, s->pending_base, s->pending_num)) { > + qemu_log_mask(LOG_GUEST_ERROR, > + "%s: Pending registers are read only\n", __func__); > + } else if (addr_between(addr, s->source_base, s->source_num)) { > + qemu_log_mask(LOG_UNIMP, > + "%s: Interrupt source mode not supported\n", __func__); > + } else if (addr_between(addr, s->priority_base, s->priority_num)) { > + uint32_t irq = ((addr - s->priority_base) >> 2) + 1; > + s->priority[irq] = value & 7; > + } else if (addr_between(addr, s->enable_base, s->enable_num)) { > + uint32_t enable_reg = (addr - s->enable_base) / 4; > + > + s->enable[enable_reg] = value; > + } else if (addr_between(addr, s->threshold_base, 1)) { > + s->threshold = value & 3; > + } else if (addr_between(addr, s->claim_base, 1)) { > + if (s->claim == value) { > + /* Interrupt was completed */ > + s->claim = 0; > + } > + } > + > + ibex_plic_update(s); > +} > + > +static const MemoryRegionOps ibex_plic_ops = { > + .read = ibex_plic_read, > + .write = ibex_plic_write, > + .endianness = DEVICE_NATIVE_ENDIAN, > + .valid = { > + .min_access_size = 4, > + .max_access_size = 4 > + } > +}; > + > +static void ibex_plic_irq_request(void *opaque, int irq, int level) > +{ > + IbexPlicState *s = opaque; > + > + ibex_plic_irqs_set_pending(s, irq, level > 0); > + ibex_plic_update(s); > +} > + > +static Property ibex_plic_properties[] = { > + DEFINE_PROP_UINT32("num-cpus", IbexPlicState, num_cpus, 1), > + DEFINE_PROP_UINT32("num-sources", IbexPlicState, num_sources, 80), > + > + DEFINE_PROP_UINT32("pending-base", IbexPlicState, pending_base, 0), > + DEFINE_PROP_UINT32("pending-num", IbexPlicState, pending_num, 3), > + > + DEFINE_PROP_UINT32("source-base", IbexPlicState, source_base, 0x0c), > + DEFINE_PROP_UINT32("source-num", IbexPlicState, source_num, 3), > + > + DEFINE_PROP_UINT32("priority-base", IbexPlicState, priority_base, 0x18), > + DEFINE_PROP_UINT32("priority-num", IbexPlicState, priority_num, 80), > + > + DEFINE_PROP_UINT32("enable-base", IbexPlicState, enable_base, 0x200), > + DEFINE_PROP_UINT32("enable-num", IbexPlicState, enable_num, 3), > + > + DEFINE_PROP_UINT32("threshold-base", IbexPlicState, threshold_base, 0x20c), > + > + DEFINE_PROP_UINT32("claim-base", IbexPlicState, claim_base, 0x210), > + DEFINE_PROP_END_OF_LIST(), > +}; > + > +static void ibex_plic_init(Object *obj) > +{ > + IbexPlicState *s = IBEX_PLIC(obj); > + > + memory_region_init_io(&s->mmio, obj, &ibex_plic_ops, s, > + TYPE_IBEX_PLIC, 0x400); > + sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio); > +} > + > +static void ibex_plic_realize(DeviceState *dev, Error **errp) > +{ > + IbexPlicState *s = IBEX_PLIC(dev); > + int i; > + > + s->pending = g_new0(uint32_t, s->pending_num); > + s->source = g_new0(uint32_t, s->source_num); > + s->priority = g_new0(uint32_t, s->priority_num); > + s->enable = g_new0(uint32_t, s->enable_num); > + > + qdev_init_gpio_in(dev, ibex_plic_irq_request, s->num_sources); > + > + /* > + * We can't allow the supervisor to control SEIP as this would allow the > + * supervisor to clear a pending external interrupt which will result in > + * a lost interrupt in the case a PLIC is attached. The SEIP bit must be > + * hardware controlled when a PLIC is attached. > + */ > + MachineState *ms = MACHINE(qdev_get_machine()); > + unsigned int smp_cpus = ms->smp.cpus; > + for (i = 0; i < smp_cpus; i++) { > + RISCVCPU *cpu = RISCV_CPU(qemu_get_cpu(i)); > + if (riscv_cpu_claim_interrupts(cpu, MIP_SEIP) < 0) { > + error_report("SEIP already claimed"); > + exit(1); > + } > + } > + > + msi_nonbroken = true; > +} > + > +static void ibex_plic_class_init(ObjectClass *klass, void *data) > +{ > + DeviceClass *dc = DEVICE_CLASS(klass); > + > + dc->reset = ibex_plic_reset; > + device_class_set_props(dc, ibex_plic_properties); > + dc->realize = ibex_plic_realize; > +} > + > +static const TypeInfo ibex_plic_info = { > + .name = TYPE_IBEX_PLIC, > + .parent = TYPE_SYS_BUS_DEVICE, > + .instance_size = sizeof(IbexPlicState), > + .instance_init = ibex_plic_init, > + .class_init = ibex_plic_class_init, > +}; > + > +static void ibex_plic_register_types(void) > +{ > + type_register_static(&ibex_plic_info); > +} > + > +type_init(ibex_plic_register_types) > diff --git a/include/hw/intc/ibex_plic.h b/include/hw/intc/ibex_plic.h > new file mode 100644 > index 0000000000..ddc7909903 > --- /dev/null > +++ b/include/hw/intc/ibex_plic.h > @@ -0,0 +1,63 @@ > +/* > + * QEMU RISC-V lowRISC Ibex PLIC > + * > + * Copyright (c) 2020 Western Digital > + * > + * 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/>. > + */ > + > +#ifndef HW_IBEX_PLIC_H > +#define HW_IBEX_PLIC_H > + > +#include "hw/sysbus.h" > + > +#define TYPE_IBEX_PLIC "ibex-plic" > +#define IBEX_PLIC(obj) \ > + OBJECT_CHECK(IbexPlicState, (obj), TYPE_IBEX_PLIC) > + > +typedef struct IbexPlicState { > + /*< private >*/ > + SysBusDevice parent_obj; > + > + /*< public >*/ > + MemoryRegion mmio; > + > + uint32_t *pending; > + uint32_t *source; > + uint32_t *priority; > + uint32_t *enable; > + uint32_t threshold; > + uint32_t claim; > + > + /* config */ > + uint32_t num_cpus; > + uint32_t num_sources; > + > + uint32_t pending_base; > + uint32_t pending_num; > + > + uint32_t source_base; > + uint32_t source_num; > + > + uint32_t priority_base; > + uint32_t priority_num; > + > + uint32_t enable_base; > + uint32_t enable_num; > + > + uint32_t threshold_base; > + > + uint32_t claim_base; > +} IbexPlicState; > + > +#endif /* HW_IBEX_PLIC_H */ >
On Thu, May 14, 2020 at 11:40 AM Philippe Mathieu-Daudé <philmd@redhat.com> wrote: > > On 5/7/20 9:13 PM, Alistair Francis wrote: > > The Ibex core contains a PLIC that although similar to the RISC-V spec > > is not RISC-V spec compliant. > > > > This patch implements a Ibex PLIC in a somewhat generic way. > > > > As the current RISC-V PLIC needs tidying up, my hope is that as the Ibex > > PLIC move towards spec compliance this PLIC implementation can be > > updated until it can replace the current PLIC. > > > > Signed-off-by: Alistair Francis <alistair.francis@wdc.com> > > --- > > MAINTAINERS | 2 + > > hw/intc/Makefile.objs | 1 + > > hw/intc/ibex_plic.c | 261 ++++++++++++++++++++++++++++++++++++ > > include/hw/intc/ibex_plic.h | 63 +++++++++ > > 4 files changed, 327 insertions(+) > > create mode 100644 hw/intc/ibex_plic.c > > create mode 100644 include/hw/intc/ibex_plic.h > > > > diff --git a/MAINTAINERS b/MAINTAINERS > > index d3d47564ce..f8c3cf6182 100644 > > --- a/MAINTAINERS > > +++ b/MAINTAINERS > > @@ -1237,8 +1237,10 @@ L: qemu-riscv@nongnu.org > > S: Supported > > F: hw/riscv/opentitan.c > > F: hw/char/ibex_uart.c > > +F: hw/intc/ibex_plic.c > > F: include/hw/riscv/opentitan.h > > F: include/hw/char/ibex_uart.h > > +F: include/hw/intc/ibex_plic.h > > > > > > SH4 Machines > > diff --git a/hw/intc/Makefile.objs b/hw/intc/Makefile.objs > > index f726d87532..a61e6728fe 100644 > > --- a/hw/intc/Makefile.objs > > +++ b/hw/intc/Makefile.objs > > @@ -49,3 +49,4 @@ obj-$(CONFIG_ARM_GIC) += arm_gicv3_cpuif.o > > obj-$(CONFIG_MIPS_CPS) += mips_gic.o > > obj-$(CONFIG_NIOS2) += nios2_iic.o > > obj-$(CONFIG_OMPIC) += ompic.o > > +obj-$(CONFIG_IBEX) += ibex_plic.o > > diff --git a/hw/intc/ibex_plic.c b/hw/intc/ibex_plic.c > > new file mode 100644 > > index 0000000000..35c52d9d16 > > --- /dev/null > > +++ b/hw/intc/ibex_plic.c > > @@ -0,0 +1,261 @@ > > +/* > > + * QEMU RISC-V lowRISC Ibex PLIC > > + * > > + * Copyright (c) 2020 Western Digital > > + * > > + * Documentation avaliable: https://docs.opentitan.org/hw/ip/rv_plic/doc/ > > + * > > + * 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 "qemu/log.h" > > +#include "hw/qdev-properties.h" > > +#include "hw/core/cpu.h" > > +#include "hw/boards.h" > > +#include "hw/pci/msi.h" > > +#include "target/riscv/cpu_bits.h" > > +#include "target/riscv/cpu.h" > > +#include "hw/intc/ibex_plic.h" > > + > > +static bool addr_between(uint32_t addr, uint32_t base, uint32_t num) > > +{ > > + uint32_t end = base + (num * 0x04); > > + > > + if (addr >= base && addr < end) { > > + return true; > > + } > > + > > + return false; > > +} > > + > > +static void ibex_plic_irqs_set_pending(IbexPlicState *s, int irq, bool level) > > +{ > > + int pending_num = irq / 32; > > + > > + s->pending[pending_num] |= level << (irq % 32); > > +} > > + > > +static bool ibex_plic_irqs_pending(IbexPlicState *s, uint32_t context) > > +{ > > + int i; > > + > > + for (i = 0; i < s->pending_num; i++) { > > + uint32_t irq_num = ctz64(s->pending[i]) + (i * 32); > > + > > + if (!(s->pending[i] & s->enable[i])) { > > + /* No pending and enabled IRQ */ > > + continue; > > + } > > + > > + if (s->priority[irq_num] > s->threshold) { > > + if (!s->claim) { > > + s->claim = irq_num; > > + } > > + return true; > > + } > > + } > > + > > + return 0; > > return 'false'. Fixed. > > > +} > > + > > +static void ibex_plic_update(IbexPlicState *s) > > +{ > > + CPUState *cpu; > > + int level, i; > > + > > + for (i = 0; i < s->num_cpus; i++) { > > + cpu = qemu_get_cpu(i); > > + > > + if (!cpu) { > > + continue; > > + } > > + > > + level = ibex_plic_irqs_pending(s, 0); > > + > > + riscv_cpu_update_mip(RISCV_CPU(cpu), MIP_MEIP, BOOL_TO_MASK(level)); > > + } > > +} > > + > > +static void ibex_plic_reset(DeviceState *dev) > > +{ > > + IbexPlicState *s = IBEX_PLIC(dev); > > + > > + s->threshold = 0x00000000; > > + s->claim = 0x00000000; > > I haven't check the datasheet reset values, for the rest: > Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Thanks for reviewing these :) Alistair
diff --git a/MAINTAINERS b/MAINTAINERS index d3d47564ce..f8c3cf6182 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1237,8 +1237,10 @@ L: qemu-riscv@nongnu.org S: Supported F: hw/riscv/opentitan.c F: hw/char/ibex_uart.c +F: hw/intc/ibex_plic.c F: include/hw/riscv/opentitan.h F: include/hw/char/ibex_uart.h +F: include/hw/intc/ibex_plic.h SH4 Machines diff --git a/hw/intc/Makefile.objs b/hw/intc/Makefile.objs index f726d87532..a61e6728fe 100644 --- a/hw/intc/Makefile.objs +++ b/hw/intc/Makefile.objs @@ -49,3 +49,4 @@ obj-$(CONFIG_ARM_GIC) += arm_gicv3_cpuif.o obj-$(CONFIG_MIPS_CPS) += mips_gic.o obj-$(CONFIG_NIOS2) += nios2_iic.o obj-$(CONFIG_OMPIC) += ompic.o +obj-$(CONFIG_IBEX) += ibex_plic.o diff --git a/hw/intc/ibex_plic.c b/hw/intc/ibex_plic.c new file mode 100644 index 0000000000..35c52d9d16 --- /dev/null +++ b/hw/intc/ibex_plic.c @@ -0,0 +1,261 @@ +/* + * QEMU RISC-V lowRISC Ibex PLIC + * + * Copyright (c) 2020 Western Digital + * + * Documentation avaliable: https://docs.opentitan.org/hw/ip/rv_plic/doc/ + * + * 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 "qemu/log.h" +#include "hw/qdev-properties.h" +#include "hw/core/cpu.h" +#include "hw/boards.h" +#include "hw/pci/msi.h" +#include "target/riscv/cpu_bits.h" +#include "target/riscv/cpu.h" +#include "hw/intc/ibex_plic.h" + +static bool addr_between(uint32_t addr, uint32_t base, uint32_t num) +{ + uint32_t end = base + (num * 0x04); + + if (addr >= base && addr < end) { + return true; + } + + return false; +} + +static void ibex_plic_irqs_set_pending(IbexPlicState *s, int irq, bool level) +{ + int pending_num = irq / 32; + + s->pending[pending_num] |= level << (irq % 32); +} + +static bool ibex_plic_irqs_pending(IbexPlicState *s, uint32_t context) +{ + int i; + + for (i = 0; i < s->pending_num; i++) { + uint32_t irq_num = ctz64(s->pending[i]) + (i * 32); + + if (!(s->pending[i] & s->enable[i])) { + /* No pending and enabled IRQ */ + continue; + } + + if (s->priority[irq_num] > s->threshold) { + if (!s->claim) { + s->claim = irq_num; + } + return true; + } + } + + return 0; +} + +static void ibex_plic_update(IbexPlicState *s) +{ + CPUState *cpu; + int level, i; + + for (i = 0; i < s->num_cpus; i++) { + cpu = qemu_get_cpu(i); + + if (!cpu) { + continue; + } + + level = ibex_plic_irqs_pending(s, 0); + + riscv_cpu_update_mip(RISCV_CPU(cpu), MIP_MEIP, BOOL_TO_MASK(level)); + } +} + +static void ibex_plic_reset(DeviceState *dev) +{ + IbexPlicState *s = IBEX_PLIC(dev); + + s->threshold = 0x00000000; + s->claim = 0x00000000; +} + +static uint64_t ibex_plic_read(void *opaque, hwaddr addr, + unsigned int size) +{ + IbexPlicState *s = opaque; + int offset; + uint32_t ret = 0; + + if (addr_between(addr, s->pending_base, s->pending_num)) { + offset = (addr - s->pending_base) / 4; + ret = s->pending[offset]; + } else if (addr_between(addr, s->source_base, s->source_num)) { + qemu_log_mask(LOG_UNIMP, + "%s: Interrupt source mode not supported\n", __func__); + } else if (addr_between(addr, s->priority_base, s->priority_num)) { + offset = (addr - s->priority_base) / 4; + ret = s->priority[offset]; + } else if (addr_between(addr, s->enable_base, s->enable_num)) { + offset = (addr - s->enable_base) / 4; + ret = s->enable[offset]; + } else if (addr_between(addr, s->threshold_base, 1)) { + ret = s->threshold; + } else if (addr_between(addr, s->claim_base, 1)) { + int pending_num = s->claim / 32; + s->pending[pending_num] &= ~(1 << (s->claim % 32)); + + ret = s->claim; + } + + return ret; +} + +static void ibex_plic_write(void *opaque, hwaddr addr, + uint64_t value, unsigned int size) +{ + IbexPlicState *s = opaque; + + if (addr_between(addr, s->pending_base, s->pending_num)) { + qemu_log_mask(LOG_GUEST_ERROR, + "%s: Pending registers are read only\n", __func__); + } else if (addr_between(addr, s->source_base, s->source_num)) { + qemu_log_mask(LOG_UNIMP, + "%s: Interrupt source mode not supported\n", __func__); + } else if (addr_between(addr, s->priority_base, s->priority_num)) { + uint32_t irq = ((addr - s->priority_base) >> 2) + 1; + s->priority[irq] = value & 7; + } else if (addr_between(addr, s->enable_base, s->enable_num)) { + uint32_t enable_reg = (addr - s->enable_base) / 4; + + s->enable[enable_reg] = value; + } else if (addr_between(addr, s->threshold_base, 1)) { + s->threshold = value & 3; + } else if (addr_between(addr, s->claim_base, 1)) { + if (s->claim == value) { + /* Interrupt was completed */ + s->claim = 0; + } + } + + ibex_plic_update(s); +} + +static const MemoryRegionOps ibex_plic_ops = { + .read = ibex_plic_read, + .write = ibex_plic_write, + .endianness = DEVICE_NATIVE_ENDIAN, + .valid = { + .min_access_size = 4, + .max_access_size = 4 + } +}; + +static void ibex_plic_irq_request(void *opaque, int irq, int level) +{ + IbexPlicState *s = opaque; + + ibex_plic_irqs_set_pending(s, irq, level > 0); + ibex_plic_update(s); +} + +static Property ibex_plic_properties[] = { + DEFINE_PROP_UINT32("num-cpus", IbexPlicState, num_cpus, 1), + DEFINE_PROP_UINT32("num-sources", IbexPlicState, num_sources, 80), + + DEFINE_PROP_UINT32("pending-base", IbexPlicState, pending_base, 0), + DEFINE_PROP_UINT32("pending-num", IbexPlicState, pending_num, 3), + + DEFINE_PROP_UINT32("source-base", IbexPlicState, source_base, 0x0c), + DEFINE_PROP_UINT32("source-num", IbexPlicState, source_num, 3), + + DEFINE_PROP_UINT32("priority-base", IbexPlicState, priority_base, 0x18), + DEFINE_PROP_UINT32("priority-num", IbexPlicState, priority_num, 80), + + DEFINE_PROP_UINT32("enable-base", IbexPlicState, enable_base, 0x200), + DEFINE_PROP_UINT32("enable-num", IbexPlicState, enable_num, 3), + + DEFINE_PROP_UINT32("threshold-base", IbexPlicState, threshold_base, 0x20c), + + DEFINE_PROP_UINT32("claim-base", IbexPlicState, claim_base, 0x210), + DEFINE_PROP_END_OF_LIST(), +}; + +static void ibex_plic_init(Object *obj) +{ + IbexPlicState *s = IBEX_PLIC(obj); + + memory_region_init_io(&s->mmio, obj, &ibex_plic_ops, s, + TYPE_IBEX_PLIC, 0x400); + sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio); +} + +static void ibex_plic_realize(DeviceState *dev, Error **errp) +{ + IbexPlicState *s = IBEX_PLIC(dev); + int i; + + s->pending = g_new0(uint32_t, s->pending_num); + s->source = g_new0(uint32_t, s->source_num); + s->priority = g_new0(uint32_t, s->priority_num); + s->enable = g_new0(uint32_t, s->enable_num); + + qdev_init_gpio_in(dev, ibex_plic_irq_request, s->num_sources); + + /* + * We can't allow the supervisor to control SEIP as this would allow the + * supervisor to clear a pending external interrupt which will result in + * a lost interrupt in the case a PLIC is attached. The SEIP bit must be + * hardware controlled when a PLIC is attached. + */ + MachineState *ms = MACHINE(qdev_get_machine()); + unsigned int smp_cpus = ms->smp.cpus; + for (i = 0; i < smp_cpus; i++) { + RISCVCPU *cpu = RISCV_CPU(qemu_get_cpu(i)); + if (riscv_cpu_claim_interrupts(cpu, MIP_SEIP) < 0) { + error_report("SEIP already claimed"); + exit(1); + } + } + + msi_nonbroken = true; +} + +static void ibex_plic_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->reset = ibex_plic_reset; + device_class_set_props(dc, ibex_plic_properties); + dc->realize = ibex_plic_realize; +} + +static const TypeInfo ibex_plic_info = { + .name = TYPE_IBEX_PLIC, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(IbexPlicState), + .instance_init = ibex_plic_init, + .class_init = ibex_plic_class_init, +}; + +static void ibex_plic_register_types(void) +{ + type_register_static(&ibex_plic_info); +} + +type_init(ibex_plic_register_types) diff --git a/include/hw/intc/ibex_plic.h b/include/hw/intc/ibex_plic.h new file mode 100644 index 0000000000..ddc7909903 --- /dev/null +++ b/include/hw/intc/ibex_plic.h @@ -0,0 +1,63 @@ +/* + * QEMU RISC-V lowRISC Ibex PLIC + * + * Copyright (c) 2020 Western Digital + * + * 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/>. + */ + +#ifndef HW_IBEX_PLIC_H +#define HW_IBEX_PLIC_H + +#include "hw/sysbus.h" + +#define TYPE_IBEX_PLIC "ibex-plic" +#define IBEX_PLIC(obj) \ + OBJECT_CHECK(IbexPlicState, (obj), TYPE_IBEX_PLIC) + +typedef struct IbexPlicState { + /*< private >*/ + SysBusDevice parent_obj; + + /*< public >*/ + MemoryRegion mmio; + + uint32_t *pending; + uint32_t *source; + uint32_t *priority; + uint32_t *enable; + uint32_t threshold; + uint32_t claim; + + /* config */ + uint32_t num_cpus; + uint32_t num_sources; + + uint32_t pending_base; + uint32_t pending_num; + + uint32_t source_base; + uint32_t source_num; + + uint32_t priority_base; + uint32_t priority_num; + + uint32_t enable_base; + uint32_t enable_num; + + uint32_t threshold_base; + + uint32_t claim_base; +} IbexPlicState; + +#endif /* HW_IBEX_PLIC_H */
The Ibex core contains a PLIC that although similar to the RISC-V spec is not RISC-V spec compliant. This patch implements a Ibex PLIC in a somewhat generic way. As the current RISC-V PLIC needs tidying up, my hope is that as the Ibex PLIC move towards spec compliance this PLIC implementation can be updated until it can replace the current PLIC. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> --- MAINTAINERS | 2 + hw/intc/Makefile.objs | 1 + hw/intc/ibex_plic.c | 261 ++++++++++++++++++++++++++++++++++++ include/hw/intc/ibex_plic.h | 63 +++++++++ 4 files changed, 327 insertions(+) create mode 100644 hw/intc/ibex_plic.c create mode 100644 include/hw/intc/ibex_plic.h