diff options
Diffstat (limited to 'target/riscv/pmu.c')
| -rw-r--r-- | target/riscv/pmu.c | 425 |
1 files changed, 423 insertions, 2 deletions
diff --git a/target/riscv/pmu.c b/target/riscv/pmu.c index 000fe8da45..b8e56d2b7b 100644 --- a/target/riscv/pmu.c +++ b/target/riscv/pmu.c @@ -19,14 +19,435 @@ #include "qemu/osdep.h" #include "cpu.h" #include "pmu.h" +#include "sysemu/cpu-timers.h" +#include "sysemu/device_tree.h" + +#define RISCV_TIMEBASE_FREQ 1000000000 /* 1Ghz */ +#define MAKE_32BIT_MASK(shift, length) \ + (((uint32_t)(~0UL) >> (32 - (length))) << (shift)) + +/* + * To keep it simple, any event can be mapped to any programmable counters in + * QEMU. The generic cycle & instruction count events can also be monitored + * using programmable counters. In that case, mcycle & minstret must continue + * to provide the correct value as well. Heterogeneous PMU per hart is not + * supported yet. Thus, number of counters are same across all harts. + */ +void riscv_pmu_generate_fdt_node(void *fdt, int num_ctrs, char *pmu_name) +{ + uint32_t fdt_event_ctr_map[20] = {}; + uint32_t cmask; + + /* All the programmable counters can map to any event */ + cmask = MAKE_32BIT_MASK(3, num_ctrs); + + /* + * The event encoding is specified in the SBI specification + * Event idx is a 20bits wide number encoded as follows: + * event_idx[19:16] = type + * event_idx[15:0] = code + * The code field in cache events are encoded as follows: + * event_idx.code[15:3] = cache_id + * event_idx.code[2:1] = op_id + * event_idx.code[0:0] = result_id + */ + + /* SBI_PMU_HW_CPU_CYCLES: 0x01 : type(0x00) */ + fdt_event_ctr_map[0] = cpu_to_be32(0x00000001); + fdt_event_ctr_map[1] = cpu_to_be32(0x00000001); + fdt_event_ctr_map[2] = cpu_to_be32(cmask | 1 << 0); + + /* SBI_PMU_HW_INSTRUCTIONS: 0x02 : type(0x00) */ + fdt_event_ctr_map[3] = cpu_to_be32(0x00000002); + fdt_event_ctr_map[4] = cpu_to_be32(0x00000002); + fdt_event_ctr_map[5] = cpu_to_be32(cmask | 1 << 2); + + /* SBI_PMU_HW_CACHE_DTLB : 0x03 READ : 0x00 MISS : 0x00 type(0x01) */ + fdt_event_ctr_map[6] = cpu_to_be32(0x00010019); + fdt_event_ctr_map[7] = cpu_to_be32(0x00010019); + fdt_event_ctr_map[8] = cpu_to_be32(cmask); + + /* SBI_PMU_HW_CACHE_DTLB : 0x03 WRITE : 0x01 MISS : 0x00 type(0x01) */ + fdt_event_ctr_map[9] = cpu_to_be32(0x0001001B); + fdt_event_ctr_map[10] = cpu_to_be32(0x0001001B); + fdt_event_ctr_map[11] = cpu_to_be32(cmask); + + /* SBI_PMU_HW_CACHE_ITLB : 0x04 READ : 0x00 MISS : 0x00 type(0x01) */ + fdt_event_ctr_map[12] = cpu_to_be32(0x00010021); + fdt_event_ctr_map[13] = cpu_to_be32(0x00010021); + fdt_event_ctr_map[14] = cpu_to_be32(cmask); + + /* This a OpenSBI specific DT property documented in OpenSBI docs */ + qemu_fdt_setprop(fdt, pmu_name, "riscv,event-to-mhpmcounters", + fdt_event_ctr_map, sizeof(fdt_event_ctr_map)); +} + +static bool riscv_pmu_counter_valid(RISCVCPU *cpu, uint32_t ctr_idx) +{ + if (ctr_idx < 3 || ctr_idx >= RV_MAX_MHPMCOUNTERS || + !(cpu->pmu_avail_ctrs & BIT(ctr_idx))) { + return false; + } else { + return true; + } +} + +static bool riscv_pmu_counter_enabled(RISCVCPU *cpu, uint32_t ctr_idx) +{ + CPURISCVState *env = &cpu->env; + + if (riscv_pmu_counter_valid(cpu, ctr_idx) && + !get_field(env->mcountinhibit, BIT(ctr_idx))) { + return true; + } else { + return false; + } +} + +static int riscv_pmu_incr_ctr_rv32(RISCVCPU *cpu, uint32_t ctr_idx) +{ + CPURISCVState *env = &cpu->env; + target_ulong max_val = UINT32_MAX; + PMUCTRState *counter = &env->pmu_ctrs[ctr_idx]; + bool virt_on = riscv_cpu_virt_enabled(env); + + /* Privilege mode filtering */ + if ((env->priv == PRV_M && + (env->mhpmeventh_val[ctr_idx] & MHPMEVENTH_BIT_MINH)) || + (env->priv == PRV_S && virt_on && + (env->mhpmeventh_val[ctr_idx] & MHPMEVENTH_BIT_VSINH)) || + (env->priv == PRV_U && virt_on && + (env->mhpmeventh_val[ctr_idx] & MHPMEVENTH_BIT_VUINH)) || + (env->priv == PRV_S && !virt_on && + (env->mhpmeventh_val[ctr_idx] & MHPMEVENTH_BIT_SINH)) || + (env->priv == PRV_U && !virt_on && + (env->mhpmeventh_val[ctr_idx] & MHPMEVENTH_BIT_UINH))) { + return 0; + } + + /* Handle the overflow scenario */ + if (counter->mhpmcounter_val == max_val) { + if (counter->mhpmcounterh_val == max_val) { + counter->mhpmcounter_val = 0; + counter->mhpmcounterh_val = 0; + /* Generate interrupt only if OF bit is clear */ + if (!(env->mhpmeventh_val[ctr_idx] & MHPMEVENTH_BIT_OF)) { + env->mhpmeventh_val[ctr_idx] |= MHPMEVENTH_BIT_OF; + riscv_cpu_update_mip(cpu, MIP_LCOFIP, BOOL_TO_MASK(1)); + } + } else { + counter->mhpmcounterh_val++; + } + } else { + counter->mhpmcounter_val++; + } + + return 0; +} + +static int riscv_pmu_incr_ctr_rv64(RISCVCPU *cpu, uint32_t ctr_idx) +{ + CPURISCVState *env = &cpu->env; + PMUCTRState *counter = &env->pmu_ctrs[ctr_idx]; + uint64_t max_val = UINT64_MAX; + bool virt_on = riscv_cpu_virt_enabled(env); + + /* Privilege mode filtering */ + if ((env->priv == PRV_M && + (env->mhpmevent_val[ctr_idx] & MHPMEVENT_BIT_MINH)) || + (env->priv == PRV_S && virt_on && + (env->mhpmevent_val[ctr_idx] & MHPMEVENT_BIT_VSINH)) || + (env->priv == PRV_U && virt_on && + (env->mhpmevent_val[ctr_idx] & MHPMEVENT_BIT_VUINH)) || + (env->priv == PRV_S && !virt_on && + (env->mhpmevent_val[ctr_idx] & MHPMEVENT_BIT_SINH)) || + (env->priv == PRV_U && !virt_on && + (env->mhpmevent_val[ctr_idx] & MHPMEVENT_BIT_UINH))) { + return 0; + } + + /* Handle the overflow scenario */ + if (counter->mhpmcounter_val == max_val) { + counter->mhpmcounter_val = 0; + /* Generate interrupt only if OF bit is clear */ + if (!(env->mhpmevent_val[ctr_idx] & MHPMEVENT_BIT_OF)) { + env->mhpmevent_val[ctr_idx] |= MHPMEVENT_BIT_OF; + riscv_cpu_update_mip(cpu, MIP_LCOFIP, BOOL_TO_MASK(1)); + } + } else { + counter->mhpmcounter_val++; + } + return 0; +} + +int riscv_pmu_incr_ctr(RISCVCPU *cpu, enum riscv_pmu_event_idx event_idx) +{ + uint32_t ctr_idx; + int ret; + CPURISCVState *env = &cpu->env; + gpointer value; + + if (!cpu->cfg.pmu_num) { + return 0; + } + value = g_hash_table_lookup(cpu->pmu_event_ctr_map, + GUINT_TO_POINTER(event_idx)); + if (!value) { + return -1; + } + + ctr_idx = GPOINTER_TO_UINT(value); + if (!riscv_pmu_counter_enabled(cpu, ctr_idx) || + get_field(env->mcountinhibit, BIT(ctr_idx))) { + return -1; + } + + if (riscv_cpu_mxl(env) == MXL_RV32) { + ret = riscv_pmu_incr_ctr_rv32(cpu, ctr_idx); + } else { + ret = riscv_pmu_incr_ctr_rv64(cpu, ctr_idx); + } + + return ret; +} bool riscv_pmu_ctr_monitor_instructions(CPURISCVState *env, uint32_t target_ctr) { - return (target_ctr == 0) ? true : false; + RISCVCPU *cpu; + uint32_t event_idx; + uint32_t ctr_idx; + + /* Fixed instret counter */ + if (target_ctr == 2) { + return true; + } + + cpu = RISCV_CPU(env_cpu(env)); + if (!cpu->pmu_event_ctr_map) { + return false; + } + + event_idx = RISCV_PMU_EVENT_HW_INSTRUCTIONS; + ctr_idx = GPOINTER_TO_UINT(g_hash_table_lookup(cpu->pmu_event_ctr_map, + GUINT_TO_POINTER(event_idx))); + if (!ctr_idx) { + return false; + } + + return target_ctr == ctr_idx ? true : false; } bool riscv_pmu_ctr_monitor_cycles(CPURISCVState *env, uint32_t target_ctr) { - return (target_ctr == 2) ? true : false; + RISCVCPU *cpu; + uint32_t event_idx; + uint32_t ctr_idx; + + /* Fixed mcycle counter */ + if (target_ctr == 0) { + return true; + } + + cpu = RISCV_CPU(env_cpu(env)); + if (!cpu->pmu_event_ctr_map) { + return false; + } + + event_idx = RISCV_PMU_EVENT_HW_CPU_CYCLES; + ctr_idx = GPOINTER_TO_UINT(g_hash_table_lookup(cpu->pmu_event_ctr_map, + GUINT_TO_POINTER(event_idx))); + + /* Counter zero is not used for event_ctr_map */ + if (!ctr_idx) { + return false; + } + + return (target_ctr == ctr_idx) ? true : false; +} + +static gboolean pmu_remove_event_map(gpointer key, gpointer value, + gpointer udata) +{ + return (GPOINTER_TO_UINT(value) == GPOINTER_TO_UINT(udata)) ? true : false; +} + +static int64_t pmu_icount_ticks_to_ns(int64_t value) +{ + int64_t ret = 0; + + if (icount_enabled()) { + ret = icount_to_ns(value); + } else { + ret = (NANOSECONDS_PER_SECOND / RISCV_TIMEBASE_FREQ) * value; + } + + return ret; +} + +int riscv_pmu_update_event_map(CPURISCVState *env, uint64_t value, + uint32_t ctr_idx) +{ + uint32_t event_idx; + RISCVCPU *cpu = RISCV_CPU(env_cpu(env)); + + if (!riscv_pmu_counter_valid(cpu, ctr_idx) || !cpu->pmu_event_ctr_map) { + return -1; + } + + /* + * Expected mhpmevent value is zero for reset case. Remove the current + * mapping. + */ + if (!value) { + g_hash_table_foreach_remove(cpu->pmu_event_ctr_map, + pmu_remove_event_map, + GUINT_TO_POINTER(ctr_idx)); + return 0; + } + + event_idx = value & MHPMEVENT_IDX_MASK; + if (g_hash_table_lookup(cpu->pmu_event_ctr_map, + GUINT_TO_POINTER(event_idx))) { + return 0; + } + + switch (event_idx) { + case RISCV_PMU_EVENT_HW_CPU_CYCLES: + case RISCV_PMU_EVENT_HW_INSTRUCTIONS: + case RISCV_PMU_EVENT_CACHE_DTLB_READ_MISS: + case RISCV_PMU_EVENT_CACHE_DTLB_WRITE_MISS: + case RISCV_PMU_EVENT_CACHE_ITLB_PREFETCH_MISS: + break; + default: + /* We don't support any raw events right now */ + return -1; + } + g_hash_table_insert(cpu->pmu_event_ctr_map, GUINT_TO_POINTER(event_idx), + GUINT_TO_POINTER(ctr_idx)); + + return 0; +} + +static void pmu_timer_trigger_irq(RISCVCPU *cpu, + enum riscv_pmu_event_idx evt_idx) +{ + uint32_t ctr_idx; + CPURISCVState *env = &cpu->env; + PMUCTRState *counter; + target_ulong *mhpmevent_val; + uint64_t of_bit_mask; + int64_t irq_trigger_at; + + if (evt_idx != RISCV_PMU_EVENT_HW_CPU_CYCLES && + evt_idx != RISCV_PMU_EVENT_HW_INSTRUCTIONS) { + return; + } + + ctr_idx = GPOINTER_TO_UINT(g_hash_table_lookup(cpu->pmu_event_ctr_map, + GUINT_TO_POINTER(evt_idx))); + if (!riscv_pmu_counter_enabled(cpu, ctr_idx)) { + return; + } + + if (riscv_cpu_mxl(env) == MXL_RV32) { + mhpmevent_val = &env->mhpmeventh_val[ctr_idx]; + of_bit_mask = MHPMEVENTH_BIT_OF; + } else { + mhpmevent_val = &env->mhpmevent_val[ctr_idx]; + of_bit_mask = MHPMEVENT_BIT_OF; + } + + counter = &env->pmu_ctrs[ctr_idx]; + if (counter->irq_overflow_left > 0) { + irq_trigger_at = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + + counter->irq_overflow_left; + timer_mod_anticipate_ns(cpu->pmu_timer, irq_trigger_at); + counter->irq_overflow_left = 0; + return; + } + + if (cpu->pmu_avail_ctrs & BIT(ctr_idx)) { + /* Generate interrupt only if OF bit is clear */ + if (!(*mhpmevent_val & of_bit_mask)) { + *mhpmevent_val |= of_bit_mask; + riscv_cpu_update_mip(cpu, MIP_LCOFIP, BOOL_TO_MASK(1)); + } + } +} + +/* Timer callback for instret and cycle counter overflow */ +void riscv_pmu_timer_cb(void *priv) +{ + RISCVCPU *cpu = priv; + + /* Timer event was triggered only for these events */ + pmu_timer_trigger_irq(cpu, RISCV_PMU_EVENT_HW_CPU_CYCLES); + pmu_timer_trigger_irq(cpu, RISCV_PMU_EVENT_HW_INSTRUCTIONS); +} + +int riscv_pmu_setup_timer(CPURISCVState *env, uint64_t value, uint32_t ctr_idx) +{ + uint64_t overflow_delta, overflow_at; + int64_t overflow_ns, overflow_left = 0; + RISCVCPU *cpu = RISCV_CPU(env_cpu(env)); + PMUCTRState *counter = &env->pmu_ctrs[ctr_idx]; + + if (!riscv_pmu_counter_valid(cpu, ctr_idx) || !cpu->cfg.ext_sscofpmf) { + return -1; + } + + if (value) { + overflow_delta = UINT64_MAX - value + 1; + } else { + overflow_delta = UINT64_MAX; + } + + /* + * QEMU supports only int64_t timers while RISC-V counters are uint64_t. + * Compute the leftover and save it so that it can be reprogrammed again + * when timer expires. + */ + if (overflow_delta > INT64_MAX) { + overflow_left = overflow_delta - INT64_MAX; + } + + if (riscv_pmu_ctr_monitor_cycles(env, ctr_idx) || + riscv_pmu_ctr_monitor_instructions(env, ctr_idx)) { + overflow_ns = pmu_icount_ticks_to_ns((int64_t)overflow_delta); + overflow_left = pmu_icount_ticks_to_ns(overflow_left) ; + } else { + return -1; + } + overflow_at = (uint64_t)qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + overflow_ns; + + if (overflow_at > INT64_MAX) { + overflow_left += overflow_at - INT64_MAX; + counter->irq_overflow_left = overflow_left; + overflow_at = INT64_MAX; + } + timer_mod_anticipate_ns(cpu->pmu_timer, overflow_at); + + return 0; +} + + +int riscv_pmu_init(RISCVCPU *cpu, int num_counters) +{ + if (num_counters > (RV_MAX_MHPMCOUNTERS - 3)) { + return -1; + } + + cpu->pmu_event_ctr_map = g_hash_table_new(g_direct_hash, g_direct_equal); + if (!cpu->pmu_event_ctr_map) { + /* PMU support can not be enabled */ + qemu_log_mask(LOG_UNIMP, "PMU events can't be supported\n"); + cpu->cfg.pmu_num = 0; + return -1; + } + + /* Create a bitmask of available programmable counters */ + cpu->pmu_avail_ctrs = MAKE_32BIT_MASK(3, num_counters); + + return 0; } |