From: "Kevenny Hsieh" <kevenny.hsieh@xxxxxxxxxxxx> Enabled Precision Time Protocol (PTP) for improved host-guest VM time synchronization, optimizing operations needing precise clock sync in virtual environment. Signed-off-by: Kevenny Hsieh <kevenny.hsieh@xxxxxxxxxxxx> Signed-off-by: Liju Chen <liju-clr.chen@xxxxxxxxxxxx> Signed-off-by: Yi-De Wu <yi-de.wu@xxxxxxxxxxxx> --- arch/arm64/geniezone/Makefile | 2 +- arch/arm64/geniezone/gzvm_arch_common.h | 3 + arch/arm64/geniezone/hvc.c | 73 +++++++++++++++++++++++++ drivers/virt/geniezone/gzvm_exception.c | 3 +- include/linux/gzvm_drv.h | 1 + include/uapi/linux/gzvm.h | 1 + 6 files changed, 80 insertions(+), 3 deletions(-) create mode 100644 arch/arm64/geniezone/hvc.c diff --git a/arch/arm64/geniezone/Makefile b/arch/arm64/geniezone/Makefile index 0e4f1087f9de..553a64a926dc 100644 --- a/arch/arm64/geniezone/Makefile +++ b/arch/arm64/geniezone/Makefile @@ -4,6 +4,6 @@ # include $(srctree)/drivers/virt/geniezone/Makefile -gzvm-y += vm.o vcpu.o vgic.o +gzvm-y += vm.o vcpu.o vgic.o hvc.o obj-$(CONFIG_MTK_GZVM) += gzvm.o diff --git a/arch/arm64/geniezone/gzvm_arch_common.h b/arch/arm64/geniezone/gzvm_arch_common.h index fbaf2da792a4..e697223f0fd6 100644 --- a/arch/arm64/geniezone/gzvm_arch_common.h +++ b/arch/arm64/geniezone/gzvm_arch_common.h @@ -93,6 +93,8 @@ static inline u16 get_vcpuid_from_tuple(unsigned int tuple) * @__pad: add an explicit '__u32 __pad;' in the middle to make it clear * what the actual layout is. * @lr: The array of LRs(list registers). + * @vtimer_offset: The offset maintained by hypervisor that is host cycle count + * when guest VM startup. * * - Keep the same layout of hypervisor data struct. * - Sync list registers back for acking virtual device interrupt status. @@ -101,6 +103,7 @@ struct gzvm_vcpu_hwstate { __le32 nr_lrs; __le32 __pad; __le64 lr[GIC_V3_NR_LRS]; + __le64 vtimer_offset; }; static inline unsigned int diff --git a/arch/arm64/geniezone/hvc.c b/arch/arm64/geniezone/hvc.c new file mode 100644 index 000000000000..603db0fad3d8 --- /dev/null +++ b/arch/arm64/geniezone/hvc.c @@ -0,0 +1,73 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2023 MediaTek Inc. + */ +#include <linux/clocksource.h> +#include <linux/kernel.h> +#include <linux/timekeeping.h> +#include <linux/gzvm_drv.h> +#include "gzvm_arch_common.h" + +#define GZVM_PTP_VIRT_COUNTER 0 +#define GZVM_PTP_PHYS_COUNTER 1 +/** + * gzvm_handle_ptp_time() - Sync time between host and guest VM + * @vcpu: Pointer to struct gzvm_vcpu_run in userspace + * @counter: Counter type from guest VM + * Return: Always return 0 because there are no cases of failure + * + * The following register values will be passed to the guest VM + * for time synchronization: + * regs->x0 (upper 32 bits) wall clock time + * regs->x1 (lower 32 bits) wall clock time + * regs->x2 (upper 32 bits) cycles + * regs->x3 (lower 32 bits) cycles + */ +static int gzvm_handle_ptp_time(struct gzvm_vcpu *vcpu, int counter) +{ + struct system_time_snapshot snapshot; + u64 cycles = 0; + + ktime_get_snapshot(&snapshot); + + switch (counter) { + case GZVM_PTP_VIRT_COUNTER: + cycles = snapshot.cycles - + le64_to_cpu(vcpu->hwstate->vtimer_offset); + break; + case GZVM_PTP_PHYS_COUNTER: + cycles = snapshot.cycles; + break; + default: + break; + } + + vcpu->run->hypercall.args[0] = upper_32_bits(snapshot.real); + vcpu->run->hypercall.args[1] = lower_32_bits(snapshot.real); + vcpu->run->hypercall.args[2] = upper_32_bits(cycles); + vcpu->run->hypercall.args[3] = lower_32_bits(cycles); + + return 0; +} + +/** + * gzvm_arch_handle_guest_hvc() - Handle architecture-related guest hvc + * @vcpu: Pointer to struct gzvm_vcpu_run in userspace + * Return: + * * true - This hvc has been processed, no need to back to VMM. + * * false - This hvc has not been processed, require userspace. + */ +bool gzvm_arch_handle_guest_hvc(struct gzvm_vcpu *vcpu) +{ + int ret, counter; + + switch (vcpu->run->hypercall.args[0]) { + case GZVM_HVC_PTP: + counter = vcpu->run->hypercall.args[1]; + ret = gzvm_handle_ptp_time(vcpu, counter); + return (ret == 0) ? true : false; + default: + break; + } + return false; +} diff --git a/drivers/virt/geniezone/gzvm_exception.c b/drivers/virt/geniezone/gzvm_exception.c index af26d1c82791..e6209b3b3a3e 100644 --- a/drivers/virt/geniezone/gzvm_exception.c +++ b/drivers/virt/geniezone/gzvm_exception.c @@ -56,7 +56,6 @@ bool gzvm_handle_guest_hvc(struct gzvm_vcpu *vcpu) ret = gzvm_handle_relinquish(vcpu, ipa); return (ret == 0) ? true : false; default: - break; + return gzvm_arch_handle_guest_hvc(vcpu); } - return false; } diff --git a/include/linux/gzvm_drv.h b/include/linux/gzvm_drv.h index a4e6c7eb9c17..fcdc6c30baea 100644 --- a/include/linux/gzvm_drv.h +++ b/include/linux/gzvm_drv.h @@ -192,6 +192,7 @@ int gzvm_handle_page_fault(struct gzvm_vcpu *vcpu); bool gzvm_handle_guest_exception(struct gzvm_vcpu *vcpu); int gzvm_handle_relinquish(struct gzvm_vcpu *vcpu, phys_addr_t ipa); bool gzvm_handle_guest_hvc(struct gzvm_vcpu *vcpu); +bool gzvm_arch_handle_guest_hvc(struct gzvm_vcpu *vcpu); int gzvm_arch_create_device(u16 vm_id, struct gzvm_create_device *gzvm_dev); int gzvm_arch_inject_irq(struct gzvm *gzvm, unsigned int vcpu_idx, diff --git a/include/uapi/linux/gzvm.h b/include/uapi/linux/gzvm.h index a98787a18c36..cd854afb445e 100644 --- a/include/uapi/linux/gzvm.h +++ b/include/uapi/linux/gzvm.h @@ -195,6 +195,7 @@ enum { /* hypercall definitions of GZVM_EXIT_HYPERCALL */ enum { + GZVM_HVC_PTP = 0x86000001, GZVM_HVC_MEM_RELINQUISH = 0xc6000009, }; -- 2.18.0