[AArch64] Improving virtualization detection from Device Tree

Author: cyring

aarch64/corefreqk.c

@@ -6297,6 +6297,19 @@ static int CoreFreqK_Ignition_Level_Up(INIT_ARG *pArg)
 	StrCopy(PUBLIC(RO(Proc))->Features.Info.Brand,
 		Arch[PUBLIC(RO(Proc))->ArchID].Architecture.Brand[0],
 		BRAND_SIZE);
+	/*	Attempt to detect virtualization from Device Tree	*/
+	#ifdef CONFIG_OF
+	{
+	    const char *virtualBoard[] = DT_VIRTUAL_BOARD;
+	    if (of_device_compatible_match(of_root, virtualBoard) > 0)
+	    {
+		PUBLIC(RO(Proc))->HypervisorID = HYPERV_KVM;
+		PUBLIC(RO(Proc))->Features.Info.Hypervisor.CRC = CRC_KVM;
+		StrCopy(PUBLIC(RO(Proc))->Features.Info.Hypervisor.ID,
+			VENDOR_KVM, 12 + 4);
+	    }
+	}
+	#endif /* CONFIG_OF */
 	/*	Check if the Processor is actually virtualized ?	*/
 	#ifdef CONFIG_XEN
 	if (xen_pv_domain() || xen_hvm_domain())

aarch64/corefreqk.h

@@ -4,6 +4,24 @@
  * Licenses: GPL2
  */
 
+#if LINUX_VERSION_CODE < KERNEL_VERSION(6, 1, 0)
+#define of_device_compatible_match(_device_, _compat_)			\
+({									\
+	const struct device_node *device = _device_;			\
+	const char *const *compat = _compat_;				\
+	unsigned int tmp, score = 0;					\
+									\
+	if (compat != NULL)						\
+		while (*compat) {					\
+			tmp = of_device_is_compatible(device, *compat); \
+			if (tmp > score)				\
+				score = tmp;				\
+			compat++;					\
+		}							\
+	score;								\
+})
+#endif
+
 #if LINUX_VERSION_CODE < KERNEL_VERSION(3, 17, 0)
 	#define sys_reg(op0, op1, crn, crm, op2) ({	\
 		UNUSED(op0);				\
@@ -146,6 +164,12 @@ ASM_COUNTERx3(x11, x12, x13, x14, ASM_RDTSC, mem_tsc, __VA_ARGS__)
 #define VENDOR_VMWARE	"VMwawarereVM"
 #define VENDOR_HYPERV	"Micrt Hvosof"
 
+#define DT_VIRTUAL_BOARD {						\
+	"linux,dummy-virt",						\
+	"qemu,pseries",							\
+	NULL								\
+}
+
 #define LATCH_NONE		0b000000000000
 #define LATCH_TGT_RATIO_UNLOCK	0b000000000001	/* <T>	TgtRatioUnlocked */
 #define LATCH_CLK_RATIO_UNLOCK	0b000000000010	/* <X>	ClkRatioUnlocked */