From 4ad1aa571214e8d6468a1806794d987b374b5a08 Mon Sep 17 00:00:00 2001 From: Anirudh Rayabharam Date: Thu, 27 Oct 2022 15:27:28 +0530 Subject: [PATCH] clocksource/drivers/hyperv: add data structure for reference TSC MSR Add a data structure to represent the reference TSC MSR similar to other MSRs. This simplifies the code for updating the MSR. Signed-off-by: Anirudh Rayabharam Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/20221027095729.1676394-2-anrayabh@linux.microsoft.com Signed-off-by: Wei Liu --- drivers/clocksource/hyperv_timer.c | 29 +++++++++++++++-------------- include/asm-generic/hyperv-tlfs.h | 9 +++++++++ 2 files changed, 24 insertions(+), 14 deletions(-) diff --git a/drivers/clocksource/hyperv_timer.c b/drivers/clocksource/hyperv_timer.c index bb47610bbd1c..18de1f439ffd 100644 --- a/drivers/clocksource/hyperv_timer.c +++ b/drivers/clocksource/hyperv_timer.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include #include @@ -395,25 +396,25 @@ static u64 notrace read_hv_sched_clock_tsc(void) static void suspend_hv_clock_tsc(struct clocksource *arg) { - u64 tsc_msr; + union hv_reference_tsc_msr tsc_msr; /* Disable the TSC page */ - tsc_msr = hv_get_register(HV_REGISTER_REFERENCE_TSC); - tsc_msr &= ~BIT_ULL(0); - hv_set_register(HV_REGISTER_REFERENCE_TSC, tsc_msr); + tsc_msr.as_uint64 = hv_get_register(HV_REGISTER_REFERENCE_TSC); + tsc_msr.enable = 0; + hv_set_register(HV_REGISTER_REFERENCE_TSC, tsc_msr.as_uint64); } static void resume_hv_clock_tsc(struct clocksource *arg) { phys_addr_t phys_addr = virt_to_phys(&tsc_pg); - u64 tsc_msr; + union hv_reference_tsc_msr tsc_msr; /* Re-enable the TSC page */ - tsc_msr = hv_get_register(HV_REGISTER_REFERENCE_TSC); - tsc_msr &= GENMASK_ULL(11, 0); - tsc_msr |= BIT_ULL(0) | (u64)phys_addr; - hv_set_register(HV_REGISTER_REFERENCE_TSC, tsc_msr); + tsc_msr.as_uint64 = hv_get_register(HV_REGISTER_REFERENCE_TSC); + tsc_msr.enable = 1; + tsc_msr.pfn = HVPFN_DOWN(phys_addr); + hv_set_register(HV_REGISTER_REFERENCE_TSC, tsc_msr.as_uint64); } #ifdef HAVE_VDSO_CLOCKMODE_HVCLOCK @@ -495,7 +496,7 @@ static __always_inline void hv_setup_sched_clock(void *sched_clock) {} static bool __init hv_init_tsc_clocksource(void) { - u64 tsc_msr; + union hv_reference_tsc_msr tsc_msr; phys_addr_t phys_addr; if (!(ms_hyperv.features & HV_MSR_REFERENCE_TSC_AVAILABLE)) @@ -530,10 +531,10 @@ static bool __init hv_init_tsc_clocksource(void) * (which already has at least the low 12 bits set to zero since * it is page aligned). Also set the "enable" bit, which is bit 0. */ - tsc_msr = hv_get_register(HV_REGISTER_REFERENCE_TSC); - tsc_msr &= GENMASK_ULL(11, 0); - tsc_msr = tsc_msr | 0x1 | (u64)phys_addr; - hv_set_register(HV_REGISTER_REFERENCE_TSC, tsc_msr); + tsc_msr.as_uint64 = hv_get_register(HV_REGISTER_REFERENCE_TSC); + tsc_msr.enable = 1; + tsc_msr.pfn = HVPFN_DOWN(phys_addr); + hv_set_register(HV_REGISTER_REFERENCE_TSC, tsc_msr.as_uint64); clocksource_register_hz(&hyperv_cs_tsc, NSEC_PER_SEC/100); diff --git a/include/asm-generic/hyperv-tlfs.h b/include/asm-generic/hyperv-tlfs.h index fdce7a4cfc6f..b17c6eeb9afa 100644 --- a/include/asm-generic/hyperv-tlfs.h +++ b/include/asm-generic/hyperv-tlfs.h @@ -102,6 +102,15 @@ struct ms_hyperv_tsc_page { volatile s64 tsc_offset; } __packed; +union hv_reference_tsc_msr { + u64 as_uint64; + struct { + u64 enable:1; + u64 reserved:11; + u64 pfn:52; + } __packed; +}; + /* * The guest OS needs to register the guest ID with the hypervisor. * The guest ID is a 64 bit entity and the structure of this ID is