diff options
| -rw-r--r-- | hw/riscv/sifive_plic.c | 505 | ||||
| -rw-r--r-- | include/hw/riscv/sifive_plic.h | 85 |
2 files changed, 590 insertions, 0 deletions
diff --git a/hw/riscv/sifive_plic.c b/hw/riscv/sifive_plic.c new file mode 100644 index 0000000000..874de2ebaf --- /dev/null +++ b/hw/riscv/sifive_plic.c @@ -0,0 +1,505 @@ +/* + * SiFive PLIC (Platform Level Interrupt Controller) + * + * Copyright (c) 2017 SiFive, Inc. + * + * This provides a parameterizable interrupt controller based on SiFive's PLIC. + * + * 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 "qemu/error-report.h" +#include "hw/sysbus.h" +#include "target/riscv/cpu.h" +#include "hw/riscv/sifive_plic.h" + +#define RISCV_DEBUG_PLIC 0 + +static PLICMode char_to_mode(char c) +{ + switch (c) { + case 'U': return PLICMode_U; + case 'S': return PLICMode_S; + case 'H': return PLICMode_H; + case 'M': return PLICMode_M; + default: + error_report("plic: invalid mode '%c'", c); + exit(1); + } +} + +static char mode_to_char(PLICMode m) +{ + switch (m) { + case PLICMode_U: return 'U'; + case PLICMode_S: return 'S'; + case PLICMode_H: return 'H'; + case PLICMode_M: return 'M'; + default: return '?'; + } +} + +static void sifive_plic_print_state(SiFivePLICState *plic) +{ + int i; + int addrid; + + /* pending */ + qemu_log("pending : "); + for (i = plic->bitfield_words - 1; i >= 0; i--) { + qemu_log("%08x", plic->pending[i]); + } + qemu_log("\n"); + + /* pending */ + qemu_log("claimed : "); + for (i = plic->bitfield_words - 1; i >= 0; i--) { + qemu_log("%08x", plic->claimed[i]); + } + qemu_log("\n"); + + for (addrid = 0; addrid < plic->num_addrs; addrid++) { + qemu_log("hart%d-%c enable: ", + plic->addr_config[addrid].hartid, + mode_to_char(plic->addr_config[addrid].mode)); + for (i = plic->bitfield_words - 1; i >= 0; i--) { + qemu_log("%08x", plic->enable[addrid * plic->bitfield_words + i]); + } + qemu_log("\n"); + } +} + +static +void sifive_plic_set_pending(SiFivePLICState *plic, int irq, bool pending) +{ + qemu_mutex_lock(&plic->lock); + uint32_t word = irq >> 5; + if (pending) { + plic->pending[word] |= (1 << (irq & 31)); + } else { + plic->pending[word] &= ~(1 << (irq & 31)); + } + qemu_mutex_unlock(&plic->lock); +} + +static +void sifive_plic_set_claimed(SiFivePLICState *plic, int irq, bool claimed) +{ + qemu_mutex_lock(&plic->lock); + uint32_t word = irq >> 5; + if (claimed) { + plic->claimed[word] |= (1 << (irq & 31)); + } else { + plic->claimed[word] &= ~(1 << (irq & 31)); + } + qemu_mutex_unlock(&plic->lock); +} + +static +int sifive_plic_num_irqs_pending(SiFivePLICState *plic, uint32_t addrid) +{ + int i, j, count = 0; + for (i = 0; i < plic->bitfield_words; i++) { + uint32_t pending_enabled_not_claimed = + (plic->pending[i] & ~plic->claimed[i]) & + plic->enable[addrid * plic->bitfield_words + i]; + if (!pending_enabled_not_claimed) { + continue; + } + for (j = 0; j < 32; j++) { + int irq = (i << 5) + j; + uint32_t prio = plic->source_priority[irq]; + int enabled = pending_enabled_not_claimed & (1 << j); + if (enabled && prio > plic->target_priority[addrid]) { + count++; + } + } + } + return count; +} + +static void sifive_plic_update(SiFivePLICState *plic) +{ + int addrid; + + /* raise irq on harts where this irq is enabled */ + for (addrid = 0; addrid < plic->num_addrs; addrid++) { + uint32_t hartid = plic->addr_config[addrid].hartid; + PLICMode mode = plic->addr_config[addrid].mode; + CPUState *cpu = qemu_get_cpu(hartid); + CPURISCVState *env = cpu ? cpu->env_ptr : NULL; + if (!env) { + continue; + } + int level = sifive_plic_num_irqs_pending(plic, addrid) > 0; + switch (mode) { + case PLICMode_M: + riscv_set_local_interrupt(RISCV_CPU(cpu), MIP_MEIP, level); + break; + case PLICMode_S: + riscv_set_local_interrupt(RISCV_CPU(cpu), MIP_SEIP, level); + break; + default: + break; + } + } + + if (RISCV_DEBUG_PLIC) { + sifive_plic_print_state(plic); + } +} + +void sifive_plic_raise_irq(SiFivePLICState *plic, uint32_t irq) +{ + sifive_plic_set_pending(plic, irq, true); + sifive_plic_update(plic); +} + +void sifive_plic_lower_irq(SiFivePLICState *plic, uint32_t irq) +{ + sifive_plic_set_pending(plic, irq, false); + sifive_plic_update(plic); +} + +static uint32_t sifive_plic_claim(SiFivePLICState *plic, uint32_t addrid) +{ + int i, j; + for (i = 0; i < plic->bitfield_words; i++) { + uint32_t pending_enabled_not_claimed = + (plic->pending[i] & ~plic->claimed[i]) & + plic->enable[addrid * plic->bitfield_words + i]; + if (!pending_enabled_not_claimed) { + continue; + } + for (j = 0; j < 32; j++) { + int irq = (i << 5) + j; + uint32_t prio = plic->source_priority[irq]; + int enabled = pending_enabled_not_claimed & (1 << j); + if (enabled && prio > plic->target_priority[addrid]) { + sifive_plic_set_pending(plic, irq, false); + sifive_plic_set_claimed(plic, irq, true); + return irq; + } + } + } + return 0; +} + +static uint64_t sifive_plic_read(void *opaque, hwaddr addr, unsigned size) +{ + SiFivePLICState *plic = opaque; + + /* writes must be 4 byte words */ + if ((addr & 0x3) != 0) { + goto err; + } + + if (addr >= plic->priority_base && /* 4 bytes per source */ + addr < plic->priority_base + (plic->num_sources << 2)) + { + uint32_t irq = (addr - plic->priority_base) >> 2; + if (RISCV_DEBUG_PLIC) { + qemu_log("plic: read priority: irq=%d priority=%d\n", + irq, plic->source_priority[irq]); + } + return plic->source_priority[irq]; + } else if (addr >= plic->pending_base && /* 1 bit per source */ + addr < plic->pending_base + (plic->num_sources >> 3)) + { + uint32_t word = (addr - plic->priority_base) >> 2; + if (RISCV_DEBUG_PLIC) { + qemu_log("plic: read pending: word=%d value=%d\n", + word, plic->pending[word]); + } + return plic->pending[word]; + } else if (addr >= plic->enable_base && /* 1 bit per source */ + addr < plic->enable_base + plic->num_addrs * plic->enable_stride) + { + uint32_t addrid = (addr - plic->enable_base) / plic->enable_stride; + uint32_t wordid = (addr & (plic->enable_stride - 1)) >> 2; + if (wordid < plic->bitfield_words) { + if (RISCV_DEBUG_PLIC) { + qemu_log("plic: read enable: hart%d-%c word=%d value=%x\n", + plic->addr_config[addrid].hartid, + mode_to_char(plic->addr_config[addrid].mode), wordid, + plic->enable[addrid * plic->bitfield_words + wordid]); + } + return plic->enable[addrid * plic->bitfield_words + wordid]; + } + } else if (addr >= plic->context_base && /* 1 bit per source */ + addr < plic->context_base + plic->num_addrs * plic->context_stride) + { + uint32_t addrid = (addr - plic->context_base) / plic->context_stride; + uint32_t contextid = (addr & (plic->context_stride - 1)); + if (contextid == 0) { + if (RISCV_DEBUG_PLIC) { + qemu_log("plic: read priority: hart%d-%c priority=%x\n", + plic->addr_config[addrid].hartid, + mode_to_char(plic->addr_config[addrid].mode), + plic->target_priority[addrid]); + } + return plic->target_priority[addrid]; + } else if (contextid == 4) { + uint32_t value = sifive_plic_claim(plic, addrid); + if (RISCV_DEBUG_PLIC) { + qemu_log("plic: read claim: hart%d-%c irq=%x\n", + plic->addr_config[addrid].hartid, + mode_to_char(plic->addr_config[addrid].mode), + value); + sifive_plic_print_state(plic); + } + return value; + } + } + +err: + error_report("plic: invalid register read: %08x", (uint32_t)addr); + return 0; +} + +static void sifive_plic_write(void *opaque, hwaddr addr, uint64_t value, + unsigned size) +{ + SiFivePLICState *plic = opaque; + + /* writes must be 4 byte words */ + if ((addr & 0x3) != 0) { + goto err; + } + + if (addr >= plic->priority_base && /* 4 bytes per source */ + addr < plic->priority_base + (plic->num_sources << 2)) + { + uint32_t irq = (addr - plic->priority_base) >> 2; + plic->source_priority[irq] = value & 7; + if (RISCV_DEBUG_PLIC) { + qemu_log("plic: write priority: irq=%d priority=%d\n", + irq, plic->source_priority[irq]); + } + return; + } else if (addr >= plic->pending_base && /* 1 bit per source */ + addr < plic->pending_base + (plic->num_sources >> 3)) + { + error_report("plic: invalid pending write: %08x", (uint32_t)addr); + return; + } else if (addr >= plic->enable_base && /* 1 bit per source */ + addr < plic->enable_base + plic->num_addrs * plic->enable_stride) + { + uint32_t addrid = (addr - plic->enable_base) / plic->enable_stride; + uint32_t wordid = (addr & (plic->enable_stride - 1)) >> 2; + if (wordid < plic->bitfield_words) { + plic->enable[addrid * plic->bitfield_words + wordid] = value; + if (RISCV_DEBUG_PLIC) { + qemu_log("plic: write enable: hart%d-%c word=%d value=%x\n", + plic->addr_config[addrid].hartid, + mode_to_char(plic->addr_config[addrid].mode), wordid, + plic->enable[addrid * plic->bitfield_words + wordid]); + } + return; + } + } else if (addr >= plic->context_base && /* 4 bytes per reg */ + addr < plic->context_base + plic->num_addrs * plic->context_stride) + { + uint32_t addrid = (addr - plic->context_base) / plic->context_stride; + uint32_t contextid = (addr & (plic->context_stride - 1)); + if (contextid == 0) { + if (RISCV_DEBUG_PLIC) { + qemu_log("plic: write priority: hart%d-%c priority=%x\n", + plic->addr_config[addrid].hartid, + mode_to_char(plic->addr_config[addrid].mode), + plic->target_priority[addrid]); + } + if (value <= plic->num_priorities) { + plic->target_priority[addrid] = value; + sifive_plic_update(plic); + } + return; + } else if (contextid == 4) { + if (RISCV_DEBUG_PLIC) { + qemu_log("plic: write claim: hart%d-%c irq=%x\n", + plic->addr_config[addrid].hartid, + mode_to_char(plic->addr_config[addrid].mode), + (uint32_t)value); + } + if (value < plic->num_sources) { + sifive_plic_set_claimed(plic, value, false); + sifive_plic_update(plic); + } + return; + } + } + +err: + error_report("plic: invalid register write: %08x", (uint32_t)addr); +} + +static const MemoryRegionOps sifive_plic_ops = { + .read = sifive_plic_read, + .write = sifive_plic_write, + .endianness = DEVICE_LITTLE_ENDIAN, + .valid = { + .min_access_size = 4, + .max_access_size = 4 + } +}; + +static Property sifive_plic_properties[] = { + DEFINE_PROP_STRING("hart-config", SiFivePLICState, hart_config), + DEFINE_PROP_UINT32("num-sources", SiFivePLICState, num_sources, 0), + DEFINE_PROP_UINT32("num-priorities", SiFivePLICState, num_priorities, 0), + DEFINE_PROP_UINT32("priority-base", SiFivePLICState, priority_base, 0), + DEFINE_PROP_UINT32("pending-base", SiFivePLICState, pending_base, 0), + DEFINE_PROP_UINT32("enable-base", SiFivePLICState, enable_base, 0), + DEFINE_PROP_UINT32("enable-stride", SiFivePLICState, enable_stride, 0), + DEFINE_PROP_UINT32("context-base", SiFivePLICState, context_base, 0), + DEFINE_PROP_UINT32("context-stride", SiFivePLICState, context_stride, 0), + DEFINE_PROP_UINT32("aperture-size", SiFivePLICState, aperture_size, 0), + DEFINE_PROP_END_OF_LIST(), +}; + +/* + * parse PLIC hart/mode address offset config + * + * "M" 1 hart with M mode + * "MS,MS" 2 harts, 0-1 with M and S mode + * "M,MS,MS,MS,MS" 5 harts, 0 with M mode, 1-5 with M and S mode + */ +static void parse_hart_config(SiFivePLICState *plic) +{ + int addrid, hartid, modes; + const char *p; + char c; + + /* count and validate hart/mode combinations */ + addrid = 0, hartid = 0, modes = 0; + p = plic->hart_config; + while ((c = *p++)) { + if (c == ',') { + addrid += __builtin_popcount(modes); + modes = 0; + hartid++; + } else { + int m = 1 << char_to_mode(c); + if (modes == (modes | m)) { + error_report("plic: duplicate mode '%c' in config: %s", + c, plic->hart_config); + exit(1); + } + modes |= m; + } + } + if (modes) { + addrid += __builtin_popcount(modes); + } + hartid++; + + /* store hart/mode combinations */ + plic->num_addrs = addrid; + plic->addr_config = g_new(PLICAddr, plic->num_addrs); + addrid = 0, hartid = 0; + p = plic->hart_config; + while ((c = *p++)) { + if (c == ',') { + hartid++; + } else { + plic->addr_config[addrid].addrid = addrid; + plic->addr_config[addrid].hartid = hartid; + plic->addr_config[addrid].mode = char_to_mode(c); + addrid++; + } + } +} + +static void sifive_plic_irq_request(void *opaque, int irq, int level) +{ + SiFivePLICState *plic = opaque; + if (RISCV_DEBUG_PLIC) { + qemu_log("sifive_plic_irq_request: irq=%d level=%d\n", irq, level); + } + sifive_plic_set_pending(plic, irq, level > 0); + sifive_plic_update(plic); +} + +static void sifive_plic_realize(DeviceState *dev, Error **errp) +{ + SiFivePLICState *plic = SIFIVE_PLIC(dev); + int i; + + memory_region_init_io(&plic->mmio, OBJECT(dev), &sifive_plic_ops, plic, + TYPE_SIFIVE_PLIC, plic->aperture_size); + parse_hart_config(plic); + qemu_mutex_init(&plic->lock); + plic->bitfield_words = (plic->num_sources + 31) >> 5; + plic->source_priority = g_new0(uint32_t, plic->num_sources); + plic->target_priority = g_new(uint32_t, plic->num_addrs); + plic->pending = g_new0(uint32_t, plic->bitfield_words); + plic->claimed = g_new0(uint32_t, plic->bitfield_words); + plic->enable = g_new0(uint32_t, plic->bitfield_words * plic->num_addrs); + sysbus_init_mmio(SYS_BUS_DEVICE(dev), &plic->mmio); + plic->irqs = g_new0(qemu_irq, plic->num_sources + 1); + for (i = 0; i <= plic->num_sources; i++) { + plic->irqs[i] = qemu_allocate_irq(sifive_plic_irq_request, plic, i); + } +} + +static void sifive_plic_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->props = sifive_plic_properties; + dc->realize = sifive_plic_realize; +} + +static const TypeInfo sifive_plic_info = { + .name = TYPE_SIFIVE_PLIC, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(SiFivePLICState), + .class_init = sifive_plic_class_init, +}; + +static void sifive_plic_register_types(void) +{ + type_register_static(&sifive_plic_info); +} + +type_init(sifive_plic_register_types) + +/* + * Create PLIC device. + */ +DeviceState *sifive_plic_create(hwaddr addr, char *hart_config, + uint32_t num_sources, uint32_t num_priorities, + uint32_t priority_base, uint32_t pending_base, + uint32_t enable_base, uint32_t enable_stride, + uint32_t context_base, uint32_t context_stride, + uint32_t aperture_size) +{ + DeviceState *dev = qdev_create(NULL, TYPE_SIFIVE_PLIC); + assert(enable_stride == (enable_stride & -enable_stride)); + assert(context_stride == (context_stride & -context_stride)); + qdev_prop_set_string(dev, "hart-config", hart_config); + qdev_prop_set_uint32(dev, "num-sources", num_sources); + qdev_prop_set_uint32(dev, "num-priorities", num_priorities); + qdev_prop_set_uint32(dev, "priority-base", priority_base); + qdev_prop_set_uint32(dev, "pending-base", pending_base); + qdev_prop_set_uint32(dev, "enable-base", enable_base); + qdev_prop_set_uint32(dev, "enable-stride", enable_stride); + qdev_prop_set_uint32(dev, "context-base", context_base); + qdev_prop_set_uint32(dev, "context-stride", context_stride); + qdev_prop_set_uint32(dev, "aperture-size", aperture_size); + qdev_init_nofail(dev); + sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, addr); + return dev; +} diff --git a/include/hw/riscv/sifive_plic.h b/include/hw/riscv/sifive_plic.h new file mode 100644 index 0000000000..11a5a98df1 --- /dev/null +++ b/include/hw/riscv/sifive_plic.h @@ -0,0 +1,85 @@ +/* + * SiFive PLIC (Platform Level Interrupt Controller) interface + * + * Copyright (c) 2017 SiFive, Inc. + * + * This provides a RISC-V PLIC device + * + * 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_SIFIVE_PLIC_H +#define HW_SIFIVE_PLIC_H + +#include "hw/irq.h" + +#define TYPE_SIFIVE_PLIC "riscv.sifive.plic" + +#define SIFIVE_PLIC(obj) \ + OBJECT_CHECK(SiFivePLICState, (obj), TYPE_SIFIVE_PLIC) + +typedef enum PLICMode { + PLICMode_U, + PLICMode_S, + PLICMode_H, + PLICMode_M +} PLICMode; + +typedef struct PLICAddr { + uint32_t addrid; + uint32_t hartid; + PLICMode mode; +} PLICAddr; + +typedef struct SiFivePLICState { + /*< private >*/ + SysBusDevice parent_obj; + + /*< public >*/ + MemoryRegion mmio; + uint32_t num_addrs; + uint32_t bitfield_words; + PLICAddr *addr_config; + uint32_t *source_priority; + uint32_t *target_priority; + uint32_t *pending; + uint32_t *claimed; + uint32_t *enable; + QemuMutex lock; + qemu_irq *irqs; + + /* config */ + char *hart_config; + uint32_t num_sources; + uint32_t num_priorities; + uint32_t priority_base; + uint32_t pending_base; + uint32_t enable_base; + uint32_t enable_stride; + uint32_t context_base; + uint32_t context_stride; + uint32_t aperture_size; +} SiFivePLICState; + +void sifive_plic_raise_irq(SiFivePLICState *plic, uint32_t irq); +void sifive_plic_lower_irq(SiFivePLICState *plic, uint32_t irq); + +DeviceState *sifive_plic_create(hwaddr addr, char *hart_config, + uint32_t num_sources, uint32_t num_priorities, + uint32_t priority_base, uint32_t pending_base, + uint32_t enable_base, uint32_t enable_stride, + uint32_t context_base, uint32_t context_stride, + uint32_t aperture_size); + +#endif + |