Re: [PATCH RFC v4 13/15] target/riscv: Introduce dynamic time frequency for virt machine

Currently, time base frequency was fixed as SIFIVE_CLINT_TIMEBASE_FREQ. Here introduce "time-frequency" property to set time base frequency dynamically of which default value is still SIFIVE_CLINT_TIMEBASE_FREQ. The virt machine uses frequency of the first cpu to create clint and fdt. Signed-off-by: Yifei Jiang <jiangyifei(a)huawei.com&gt; Signed-off-by: Yipeng Yin <yinyipeng1(a)huawei.com&gt; --- hw/riscv/virt.c | 18 ++++++++++++++---- target/riscv/cpu.c | 3 +++ target/riscv/cpu.h | 2 ++ 3 files changed, 19 insertions(+), 4 deletions(-) diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c index 47b7018193..788a7237b6 100644 --- a/hw/riscv/virt.c +++ b/hw/riscv/virt.c @@ -178,7 +178,7 @@ static void create_pcie_irq_map(void *fdt, char *nodename, } static void create_fdt(RISCVVirtState *s, const struct MemmapEntry *memmap, - uint64_t mem_size, const char *cmdline) + uint64_t mem_size, const char *cmdline, uint64_t timebase_frequency) { void *fdt; int i, cpu, socket; @@ -225,7 +225,7 @@ static void create_fdt(RISCVVirtState *s, const struct MemmapEntry *memmap, qemu_fdt_add_subnode(fdt, "/cpus"); qemu_fdt_setprop_cell(fdt, "/cpus", "timebase-frequency", - SIFIVE_CLINT_TIMEBASE_FREQ); + timebase_frequency); qemu_fdt_setprop_cell(fdt, "/cpus", "#size-cells", 0x0); qemu_fdt_setprop_cell(fdt, "/cpus", "#address-cells", 0x1); qemu_fdt_add_subnode(fdt, "/cpus/cpu-map"); @@ -510,6 +510,7 @@ static void virt_machine_init(MachineState *machine) target_ulong firmware_end_addr, kernel_start_addr; uint32_t fdt_load_addr; uint64_t kernel_entry; + uint64_t timebase_frequency = 0; DeviceState *mmio_plic, *virtio_plic, *pcie_plic; int i, j, base_hartid, hart_count; CPUState *cs; @@ -553,12 +554,20 @@ static void virt_machine_init(MachineState *machine) hart_count, &error_abort); sysbus_realize(SYS_BUS_DEVICE(&s->soc[i]), &error_abort); + if (!timebase_frequency) { + timebase_frequency = RISCV_CPU(first_cpu)->env.frequency; + } + /* If vcpu's time frequency is not specified, we use default frequency */ + if (!timebase_frequency) { + timebase_frequency = SIFIVE_CLINT_TIMEBASE_FREQ; + } + /* Per-socket CLINT */ sifive_clint_create( memmap[VIRT_CLINT].base + i * memmap[VIRT_CLINT].size, memmap[VIRT_CLINT].size, base_hartid, hart_count, SIFIVE_SIP_BASE, SIFIVE_TIMECMP_BASE, SIFIVE_TIME_BASE, - SIFIVE_CLINT_TIMEBASE_FREQ, true); + timebase_frequency, true); /* Per-socket PLIC hart topology configuration string */ plic_hart_config_len = @@ -610,7 +619,8 @@ static void virt_machine_init(MachineState *machine) main_mem); /* create device tree */ - create_fdt(s, memmap, machine->ram_size, machine->kernel_cmdline); + create_fdt(s, memmap, machine->ram_size, machine->kernel_cmdline, + timebase_frequency); /* boot rom */ memory_region_init_rom(mask_rom, NULL, "riscv_virt_board.mrom", diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c index 439dc89ee7..66f35bcbbf 100644 --- a/target/riscv/cpu.c +++ b/target/riscv/cpu.c @@ -494,6 +494,8 @@ static void riscv_cpu_realize(DeviceState *dev, Error **errp) riscv_cpu_register_gdb_regs_for_features(cs); + env->user_frequency = env->frequency; + qemu_init_vcpu(cs); cpu_reset(cs); @@ -531,6 +533,7 @@ static Property riscv_cpu_properties[] = { DEFINE_PROP_BOOL("mmu", RISCVCPU, cfg.mmu, true), DEFINE_PROP_BOOL("pmp", RISCVCPU, cfg.pmp, true), DEFINE_PROP_UINT64("resetvec", RISCVCPU, cfg.resetvec, DEFAULT_RSTVEC), + DEFINE_PROP_UINT64("time-frequency", RISCVCPU, env.frequency, 0),

DEFINE_PROP_END_OF_LIST(), }; diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h index 16d6050ead..f5b6c34176 100644 --- a/target/riscv/cpu.h +++ b/target/riscv/cpu.h @@ -243,6 +243,8 @@ struct CPURISCVState { uint64_t kvm_timer_time; uint64_t kvm_timer_compare; uint64_t kvm_timer_state; + uint64_t user_frequency; + uint64_t frequency; }; OBJECT_DECLARE_TYPE(RISCVCPU, RISCVCPUClass, -- 2.19.1