RE: [PATCH v2 06/12] target/riscv: Support start kernel directly by KVM

-----Original Message----- From: Anup Patel [mailto:anup@brainfault.org] Sent: Monday, December 13, 2021 12:21 PM To: Jiangyifei <jiangyifei(a)huawei.com&gt; Cc: QEMU Developers <qemu-devel(a)nongnu.org>; open list:RISC-V <qemu-riscv(a)nongnu.org>; kvm-riscv(a)lists.infradead.org; KVM General <kvm(a)vger.kernel.org>; libvir-list(a)redhat.com; Anup Patel <anup.patel(a)wdc.com>; Palmer Dabbelt <palmer(a)dabbelt.com>; Alistair Francis <Alistair.Francis(a)wdc.com>; Bin Meng <bin.meng(a)windriver.com>; Fanliang (EulerOS) <fanliang(a)huawei.com>; Wubin (H) <wu.wubin(a)huawei.com>; Wanghaibin (D) <wanghaibin.wang(a)huawei.com>; wanbo (G) <wanbo13(a)huawei.com>; limingwang (A) <limingwang(a)huawei.com&gt; Subject: Re: [PATCH v2 06/12] target/riscv: Support start kernel directly by KVM On Fri, Dec 10, 2021 at 3:37 PM Yifei Jiang <jiangyifei(a)huawei.com&gt; wrote: > > Get kernel and fdt start address in virt.c, and pass them to KVM when > cpu reset. In addition, add kvm_riscv.h to place riscv specific > interface. > > Signed-off-by: Yifei Jiang <jiangyifei(a)huawei.com&gt; > Signed-off-by: Mingwang Li <limingwang(a)huawei.com&gt; > Reviewed-by: Alistair Francis <alistair.francis(a)wdc.com&gt; > --- > hw/riscv/boot.c | 11 ++++++++ > hw/riscv/virt.c | 54 ++++++++++++++++++++++++++++------------ > include/hw/riscv/boot.h | 1 + > target/riscv/cpu.c | 8 ++++++ > target/riscv/cpu.h | 3 +++ > target/riscv/kvm-stub.c | 25 +++++++++++++++++++ > target/riscv/kvm.c | 14 +++++++++++ > target/riscv/kvm_riscv.h | 24 ++++++++++++++++++ > target/riscv/meson.build | 2 +- > 9 files changed, 125 insertions(+), 17 deletions(-) create mode > 100644 target/riscv/kvm-stub.c create mode 100644 > target/riscv/kvm_riscv.h > > diff --git a/hw/riscv/boot.c b/hw/riscv/boot.c index > 519fa455a1..00df6d7810 100644 > --- a/hw/riscv/boot.c > +++ b/hw/riscv/boot.c > @@ -317,3 +317,14 @@ void riscv_setup_rom_reset_vec(MachineState > *machine, RISCVHartArrayState *harts > > return; > } > + > +void riscv_setup_direct_kernel(hwaddr kernel_addr, hwaddr fdt_addr) { > + CPUState *cs; > + > + for (cs = first_cpu; cs; cs = CPU_NEXT(cs)) { > + RISCVCPU *riscv_cpu = RISCV_CPU(cs); > + riscv_cpu->env.kernel_addr = kernel_addr; > + riscv_cpu->env.fdt_addr = fdt_addr; > + } > +} > diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c index > 3af074148e..c8bcd9d9e5 100644 > --- a/hw/riscv/virt.c > +++ b/hw/riscv/virt.c > @@ -38,6 +38,7 @@ > #include "chardev/char.h" > #include "sysemu/device_tree.h" > #include "sysemu/sysemu.h" > +#include "sysemu/kvm.h" > #include "hw/pci/pci.h" > #include "hw/pci-host/gpex.h" > #include "hw/display/ramfb.h" > @@ -801,23 +802,25 @@ static void virt_machine_init(MachineState *machine) > hart_count, &error_abort); > sysbus_realize(SYS_BUS_DEVICE(&s->soc[i]), &error_abort); > > - /* Per-socket CLINT */ > - riscv_aclint_swi_create( > - memmap[VIRT_CLINT].base + i * memmap[VIRT_CLINT].size, > - base_hartid, hart_count, false); > - riscv_aclint_mtimer_create( > - memmap[VIRT_CLINT].base + i * memmap[VIRT_CLINT].size + > - RISCV_ACLINT_SWI_SIZE, > - RISCV_ACLINT_DEFAULT_MTIMER_SIZE, base_hartid, hart_count, > - RISCV_ACLINT_DEFAULT_MTIMECMP, RISCV_ACLINT_DEFAULT_MTIME, > - RISCV_ACLINT_DEFAULT_TIMEBASE_FREQ, true); > - > - /* Per-socket ACLINT SSWI */ > - if (s->have_aclint) { > + if (!kvm_enabled()) { > + /* Per-socket CLINT */ > riscv_aclint_swi_create( > - memmap[VIRT_ACLINT_SSWI].base + > - i * memmap[VIRT_ACLINT_SSWI].size, > - base_hartid, hart_count, true); > + memmap[VIRT_CLINT].base + i * memmap[VIRT_CLINT].size, > + base_hartid, hart_count, false); > + riscv_aclint_mtimer_create( > + memmap[VIRT_CLINT].base + i * memmap[VIRT_CLINT].size + > + RISCV_ACLINT_SWI_SIZE, > + RISCV_ACLINT_DEFAULT_MTIMER_SIZE, base_hartid, hart_count, > + RISCV_ACLINT_DEFAULT_MTIMECMP, RISCV_ACLINT_DEFAULT_MTIME, > + RISCV_ACLINT_DEFAULT_TIMEBASE_FREQ, true); > + > + /* Per-socket ACLINT SSWI */ > + if (s->have_aclint) { > + riscv_aclint_swi_create( > + memmap[VIRT_ACLINT_SSWI].base + > + i * memmap[VIRT_ACLINT_SSWI].size, > + base_hartid, hart_count, true); > + } Along with this, we should not generate FDT nodes of ACLINT (or SiFive CLINT) when KVM is enabled.

> } > > /* Per-socket PLIC hart topology configuration string */ @@ > -884,6 +887,16 @@ static void virt_machine_init(MachineState *machine) > memory_region_add_subregion(system_memory, memmap[VIRT_MROM].base, > mask_rom); > > + /* > + * Only direct boot kernel is currently supported for KVM VM, > + * so the "-bios" parameter is ignored and treated like "-bios none" > + * when KVM is enabled. > + */ > + if (kvm_enabled()) { > + g_free(machine->firmware); > + machine->firmware = g_strdup("none"); > + } > + > if (riscv_is_32bit(&s->soc[0])) { > firmware_end_addr = riscv_find_and_load_firmware(machine, > RISCV32_BIOS_BIN, start_addr, > NULL); @@ -941,6 +954,15 @@ static void virt_machine_init(MachineState *machine) > virt_memmap[VIRT_MROM].size, kernel_entry, > fdt_load_addr, machine->fdt); > > + /* > + * Only direct boot kernel is currently supported for KVM VM, > + * So here setup kernel start address and fdt address. > + * TODO:Support firmware loading and integrate to TCG start > + */ > + if (kvm_enabled()) { > + riscv_setup_direct_kernel(kernel_entry, fdt_load_addr); > + } > + > /* SiFive Test MMIO device */ > sifive_test_create(memmap[VIRT_TEST].base); > > diff --git a/include/hw/riscv/boot.h b/include/hw/riscv/boot.h index > baff11dd8a..5834c234aa 100644 > --- a/include/hw/riscv/boot.h > +++ b/include/hw/riscv/boot.h > @@ -58,5 +58,6 @@ void riscv_rom_copy_firmware_info(MachineState *machine, hwaddr rom_base, > hwaddr rom_size, > uint32_t reset_vec_size, > uint64_t kernel_entry); > +void riscv_setup_direct_kernel(hwaddr kernel_addr, hwaddr fdt_addr); > > #endif /* RISCV_BOOT_H */ > diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c index > f812998123..1c944872a3 100644 > --- a/target/riscv/cpu.c > +++ b/target/riscv/cpu.c > @@ -29,6 +29,8 @@ > #include "hw/qdev-properties.h" > #include "migration/vmstate.h" > #include "fpu/softfloat-helpers.h" > +#include "sysemu/kvm.h" > +#include "kvm_riscv.h" > > /* RISC-V CPU definitions */ > > @@ -380,6 +382,12 @@ static void riscv_cpu_reset(DeviceState *dev) > cs->exception_index = RISCV_EXCP_NONE; > env->load_res = -1; > set_default_nan_mode(1, &env->fp_status); > + > +#ifndef CONFIG_USER_ONLY > + if (kvm_enabled()) { > + kvm_riscv_reset_vcpu(cpu); > + } > +#endif > } > > static void riscv_cpu_disas_set_info(CPUState *s, disassemble_info > *info) diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h index > 0760c0af93..2807eb1bcb 100644 > --- a/target/riscv/cpu.h > +++ b/target/riscv/cpu.h > @@ -255,6 +255,9 @@ struct CPURISCVState { > > /* Fields from here on are preserved across CPU reset. */ > QEMUTimer *timer; /* Internal timer */ > + > + hwaddr kernel_addr; > + hwaddr fdt_addr; > }; > > OBJECT_DECLARE_TYPE(RISCVCPU, RISCVCPUClass, diff --git > a/target/riscv/kvm-stub.c b/target/riscv/kvm-stub.c new file mode > 100644 index 0000000000..39b96fe3f4 > --- /dev/null > +++ b/target/riscv/kvm-stub.c > @@ -0,0 +1,25 @@ > +/* > + * QEMU KVM RISC-V specific function stubs > + * > + * Copyright (c) 2020 Huawei Technologies Co., Ltd > + * > + * 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 "cpu.h" > +#include "kvm_riscv.h" > + > +void kvm_riscv_reset_vcpu(RISCVCPU *cpu) { > + abort(); > +} > diff --git a/target/riscv/kvm.c b/target/riscv/kvm.c index > e695b91dc7..db6d8a5b6e 100644 > --- a/target/riscv/kvm.c > +++ b/target/riscv/kvm.c > @@ -37,6 +37,7 @@ > #include "hw/irq.h" > #include "qemu/log.h" > #include "hw/loader.h" > +#include "kvm_riscv.h" > > static uint64_t kvm_riscv_reg_id(CPURISCVState *env, uint64_t type, > uint64_t idx) { @@ -369,6 +370,19 @@ int > kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run) > return 0; > } > > +void kvm_riscv_reset_vcpu(RISCVCPU *cpu) { > + CPURISCVState *env = &cpu->env; > + > + if (!kvm_enabled()) { > + return; > + } > + env->pc = cpu->env.kernel_addr; > + env->gpr[10] = kvm_arch_vcpu_id(CPU(cpu)); /* a0 */ > + env->gpr[11] = cpu->env.fdt_addr; /* a1 */ > + env->satp = 0; > +} > + > bool kvm_arch_cpu_check_are_resettable(void) > { > return true; > diff --git a/target/riscv/kvm_riscv.h b/target/riscv/kvm_riscv.h new > file mode 100644 index 0000000000..f38c82bf59 > --- /dev/null > +++ b/target/riscv/kvm_riscv.h > @@ -0,0 +1,24 @@ > +/* > + * QEMU KVM support -- RISC-V specific functions. > + * > + * Copyright (c) 2020 Huawei Technologies Co., Ltd > + * > + * 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 QEMU_KVM_RISCV_H > +#define QEMU_KVM_RISCV_H > + > +void kvm_riscv_reset_vcpu(RISCVCPU *cpu); > + > +#endif > diff --git a/target/riscv/meson.build b/target/riscv/meson.build index > 2faf08a941..fe41cc5805 100644 > --- a/target/riscv/meson.build > +++ b/target/riscv/meson.build > @@ -19,7 +19,7 @@ riscv_ss.add(files( > 'bitmanip_helper.c', > 'translate.c', > )) > -riscv_ss.add(when: 'CONFIG_KVM', if_true: files('kvm.c')) > +riscv_ss.add(when: 'CONFIG_KVM', if_true: files('kvm.c'), if_false: > +files('kvm-stub.c')) > > riscv_softmmu_ss = ss.source_set() > riscv_softmmu_ss.add(files( > -- > 2.19.1 > Regards, Anup