Merge feature/arm64-hyperv-synthetic-clocks-timers/6.6 into v6.6.75

* commit '27ff58a87b8e8f33461b2443efe4dfa6487ad352':
  x86/hyperv: Don’t enable TSCInvariant on some older Hyper-V hosts
  mshyperv: Introduce hv_get_hypervisor_version function
  arm64: hyperv: Fix build breakage for non-ARM64 architectures
  arm64: hyperv: Enable Hyper-V synthetic clocks/timers

Author: chessturo

arch/arm64/hyperv/mshyperv.c

@@ -19,23 +19,29 @@
 
 static bool hyperv_initialized;
 
-static int __init hyperv_init(void)
+int hv_get_hypervisor_version(union hv_hypervisor_version_info *info)
+{
+	hv_get_vpreg_128(HV_REGISTER_HYPERVISOR_VERSION,
+			 (struct hv_get_vp_registers_output *)info);
+
+	return 0;
+}
+
+void __init hyperv_early_init(void)
 {
 	struct hv_get_vp_registers_output	result;
-	u32	a, b, c, d;
 	u64	guest_id;
-	int	ret;
 
 	/*
 	 * Allow for a kernel built with CONFIG_HYPERV to be running in
 	 * a non-Hyper-V environment, including on DT instead of ACPI.
 	 * In such cases, do nothing and return success.
 	 */
 	if (acpi_disabled)
-		return 0;
+		return;
 
 	if (strncmp((char *)&acpi_gbl_FADT.hypervisor_id, "MsHyperV", 8))
-		return 0;
+		return;
 
 	/* Setup the guest ID */
 	guest_id = hv_generate_guest_id(LINUX_VERSION_CODE);
@@ -54,14 +60,12 @@ static int __init hyperv_init(void)
 		ms_hyperv.features, ms_hyperv.priv_high, ms_hyperv.hints,
 		ms_hyperv.misc_features);
 
-	/* Get information about the Hyper-V host version */
-	hv_get_vpreg_128(HV_REGISTER_HYPERVISOR_VERSION, &result);
-	a = result.as32.a;
-	b = result.as32.b;
-	c = result.as32.c;
-	d = result.as32.d;
-	pr_info("Hyper-V: Host Build %d.%d.%d.%d-%d-%d\n",
-		b >> 16, b & 0xFFFF, a,	d & 0xFFFFFF, c, d >> 24);
+	hyperv_initialized = true;
+}
+
+static int __init hyperv_init(void)
+{
+	int ret;
 
 	ret = hv_common_init();
 	if (ret)
@@ -74,7 +78,6 @@ static int __init hyperv_init(void)
 		return ret;
 	}
 
-	hyperv_initialized = true;
 	return 0;
 }
 

arch/arm64/include/asm/hyperv_timer.h

@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_ARM64_HYPERV_TIMER_H
+#define _ASM_ARM64_HYPERV_TIMER_H
+
+#include <asm/mshyperv.h>
+
+#endif

arch/arm64/include/asm/mshyperv.h

@@ -21,6 +21,13 @@
 #include <linux/types.h>
 #include <linux/arm-smccc.h>
 #include <asm/hyperv-tlfs.h>
+#include <clocksource/arm_arch_timer.h>
+
+#if IS_ENABLED(CONFIG_HYPERV)
+void __init hyperv_early_init(void);
+#else
+static inline void hyperv_early_init(void) {};
+#endif
 
 extern u64 hv_do_hvc(u64 control, ...);
 extern u64 hv_do_hvc_fast_get(u64 control, u64 input1, u64 input2, u64 input3,
@@ -45,6 +52,17 @@ static inline u64 hv_get_register(unsigned int reg)
 	return hv_get_vpreg(reg);
 }
 
+/* Define the interrupt ID used by STIMER0 Direct Mode interrupts. This
+ * value can't come from ACPI tables because it is needed before the
+ * Linux ACPI subsystem is initialized.
+ */
+#define HYPERV_STIMER0_VECTOR	31
+
+static inline u64 hv_get_raw_timer(void)
+{
+	return arch_timer_read_counter();
+}
+
 /* SMCCC hypercall parameters */
 #define HV_SMCCC_FUNC_NUMBER	1
 #define HV_FUNC_ID	ARM_SMCCC_CALL_VAL(			\

arch/arm64/kernel/setup.c

@@ -52,6 +52,7 @@
 #include <asm/traps.h>
 #include <asm/efi.h>
 #include <asm/xen/hypervisor.h>
+#include <asm/mshyperv.h>
 #include <asm/mmu_context.h>
 
 static int num_standard_resources;
@@ -358,6 +359,9 @@ void __init __no_sanitize_address setup_arch(char **cmdline_p)
 	if (acpi_disabled)
 		unflatten_device_tree();
 
+	/* Do after acpi_boot_table_init() so local FADT is available */
+	hyperv_early_init();
+
 	bootmem_init();
 
 	kasan_init();

arch/x86/kernel/cpu/mshyperv.c

@@ -404,13 +404,26 @@ static void __init reduced_hw_init(void)
 	x86_init.irqs.pre_vector_init	= x86_init_noop;
 }
 
+int hv_get_hypervisor_version(union hv_hypervisor_version_info *info)
+{
+	unsigned int hv_max_functions;
+
+	hv_max_functions = cpuid_eax(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS);
+	if (hv_max_functions < HYPERV_CPUID_VERSION) {
+		pr_err("%s: Could not detect Hyper-V version\n", __func__);
+		return -ENODEV;
+	}
+
+	cpuid(HYPERV_CPUID_VERSION, &info->eax, &info->ebx, &info->ecx, &info->edx);
+
+	return 0;
+}
+
 static void __init ms_hyperv_init_platform(void)
 {
+	union hv_hypervisor_version_info version;
+	unsigned int build = 0;
 	int hv_max_functions_eax;
-	int hv_host_info_eax;
-	int hv_host_info_ebx;
-	int hv_host_info_ecx;
-	int hv_host_info_edx;
 
 #ifdef CONFIG_PARAVIRT
 	pv_info.name = "Hyper-V";
@@ -436,6 +449,18 @@ static void __init ms_hyperv_init_platform(void)
 	pr_debug("Hyper-V: max %u virtual processors, %u logical processors\n",
 		 ms_hyperv.max_vp_index, ms_hyperv.max_lp_index);
 
+	/*
+	 * Host builds earlier than 22621 (Win 11 22H2) have a bug in the
+	 * invariant TSC feature that may result in the guest seeing a "slow"
+	 * TSC after host hibernation. This causes problems with synthetic
+	 * timer interrupts. In such a case, avoid the bug by assuming the
+	 * feature is not present.
+	 */
+	if (!hv_get_hypervisor_version(&version))
+		build = version.build_number;
+	if (build < 22621)
+		ms_hyperv.features &= ~HV_ACCESS_TSC_INVARIANT;
+
 	/*
 	 * Check CPU management privilege.
 	 *
@@ -461,21 +486,6 @@ static void __init ms_hyperv_init_platform(void)
 		pr_info("Hyper-V: running on a nested hypervisor\n");
 	}
 
-	/*
-	 * Extract host information.
-	 */
-	if (hv_max_functions_eax >= HYPERV_CPUID_VERSION) {
-		hv_host_info_eax = cpuid_eax(HYPERV_CPUID_VERSION);
-		hv_host_info_ebx = cpuid_ebx(HYPERV_CPUID_VERSION);
-		hv_host_info_ecx = cpuid_ecx(HYPERV_CPUID_VERSION);
-		hv_host_info_edx = cpuid_edx(HYPERV_CPUID_VERSION);
-
-		pr_info("Hyper-V: Host Build %d.%d.%d.%d-%d-%d\n",
-			hv_host_info_ebx >> 16, hv_host_info_ebx & 0xFFFF,
-			hv_host_info_eax, hv_host_info_edx & 0xFFFFFF,
-			hv_host_info_ecx, hv_host_info_edx >> 24);
-	}
-
 	if (ms_hyperv.features & HV_ACCESS_FREQUENCY_MSRS &&
 	    ms_hyperv.misc_features & HV_FEATURE_FREQUENCY_MSRS_AVAILABLE) {
 		x86_platform.calibrate_tsc = hv_get_tsc_khz;

drivers/clocksource/hyperv_timer.c

@@ -377,7 +377,11 @@ static __always_inline u64 read_hv_clock_msr(void)
 	 * noinstr. Notable; while HV_REGISTER_TIME_REF_COUNT is a synthetic
 	 * register it doesn't need the GHCB path.
 	 */
+#ifdef CONFIG_ARM64
+	return hv_get_register(HV_REGISTER_TIME_REF_COUNT);
+#else
 	return hv_raw_get_register(HV_REGISTER_TIME_REF_COUNT);
+#endif
 }
 
 /*
@@ -391,7 +395,12 @@ static __always_inline u64 read_hv_clock_msr(void)
 static union {
 	struct ms_hyperv_tsc_page page;
 	u8 reserved[PAGE_SIZE];
-} tsc_pg __bss_decrypted __aligned(PAGE_SIZE);
+} tsc_pg
+#ifdef CONFIG_ARM64
+    __aligned(PAGE_SIZE);
+#else
+    __bss_decrypted __aligned(PAGE_SIZE);
+#endif
 
 static struct ms_hyperv_tsc_page *tsc_page = &tsc_pg.page;
 static unsigned long tsc_pfn;
@@ -624,3 +633,17 @@ void __init hv_remap_tsc_clocksource(void)
 	if (!tsc_page)
 		pr_err("Failed to remap Hyper-V TSC page.\n");
 }
+
+/* Initialize everything on ARM64 */
+static int __init hyperv_timer_init(struct acpi_table_header *table)
+{
+	if (!hv_is_hyperv_initialized())
+		return -EINVAL;
+
+	hv_init_clocksource();
+	if (hv_stimer_alloc(true))
+		return -EINVAL;
+
+	return 0;
+}
+TIMER_ACPI_DECLARE(hyperv, ACPI_SIG_GTDT, hyperv_timer_init);

drivers/hv/Kconfig

@@ -39,7 +39,7 @@ config HYPERV_VTL_MODE
 	  If unsure, say N
 
 config HYPERV_TIMER
-	def_bool HYPERV && X86
+	def_bool HYPERV
 
 config HYPERV_UTILS
 	tristate "Microsoft Hyper-V Utilities driver"

drivers/hv/hv_common.c

@@ -279,6 +279,14 @@ static void hv_kmsg_dump_register(void)
 int __init hv_common_init(void)
 {
 	int i;
+	union hv_hypervisor_version_info version;
+
+	/* Get information about the Hyper-V host version */
+	if (!hv_get_hypervisor_version(&version))
+		pr_info("Hyper-V: Host Build %d.%d.%d.%d-%d-%d\n",
+			version.major_version, version.minor_version,
+			version.build_number, version.service_number,
+			version.service_pack, version.service_branch);
 
 	if (hv_is_isolation_supported())
 		sysctl_record_panic_msg = 0;

include/asm-generic/hyperv-tlfs.h

@@ -787,6 +787,29 @@ struct hv_input_unmap_device_interrupt {
 #define HV_SOURCE_SHADOW_NONE               0x0
 #define HV_SOURCE_SHADOW_BRIDGE_BUS_RANGE   0x1
 
+/*
+ * Version info reported by hypervisor
+ */
+union hv_hypervisor_version_info {
+	struct {
+		u32 build_number;
+
+		u32 minor_version : 16;
+		u32 major_version : 16;
+
+		u32 service_pack;
+
+		u32 service_number : 24;
+		u32 service_branch : 8;
+	};
+	struct {
+		u32 eax;
+		u32 ebx;
+		u32 ecx;
+		u32 edx;
+	};
+};
+
 /*
  * The whole argument should fit in a page to be able to pass to the hypervisor
  * in one hypercall.

include/asm-generic/mshyperv.h

@@ -275,6 +275,7 @@ static inline int cpumask_to_vpset_skip(struct hv_vpset *vpset,
 	return __cpumask_to_vpset(vpset, cpus, func);
 }
 
+int hv_get_hypervisor_version(union hv_hypervisor_version_info *info);
 void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die);
 bool hv_is_hyperv_initialized(void);
 bool hv_is_hibernation_supported(void);