arm64: add read_cpuid_{implementor,part_number,mpidr}

In order to preserve some kind of source compatibility between
arm and arm64, introduce read_cpuid_{implementor,part_number,mpidr}
which are used on KVM to find out which CPU we're running on.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/include/asm/cputype.h

@@ -17,6 +17,7 @@
 #define __ASM_CPUTYPE_H
 
 #define ID_MIDR_EL1		"midr_el1"
+#define ID_MPIDR_EL1		"mpidr_el1"
 #define ID_CTR_EL0		"ctr_el0"
 
 #define ID_AA64PFR0_EL1		"id_aa64pfr0_el1"
@@ -31,6 +32,12 @@
 	__val;								\
 })
 
+#define ARM_CPU_IMP_ARM		0x41
+
+#define ARM_CPU_PART_AEM_V8	0xD0F0
+#define ARM_CPU_PART_FOUNDATION	0xD000
+#define ARM_CPU_PART_CORTEX_A57	0xD070
+
 /*
  * The CPU ID never changes at run time, so we might as well tell the
  * compiler that it's constant.  Use this function to read the CPU ID
@@ -41,6 +48,21 @@ static inline u32 __attribute_const__ read_cpuid_id(void)
 	return read_cpuid(ID_MIDR_EL1);
 }
 
+static inline u64 __attribute_const__ read_cpuid_mpidr(void)
+{
+	return read_cpuid(ID_MPIDR_EL1);
+}
+
+static inline unsigned int __attribute_const__ read_cpuid_implementor(void)
+{
+	return (read_cpuid_id() & 0xFF000000) >> 24;
+}
+
+static inline unsigned int __attribute_const__ read_cpuid_part_number(void)
+{
+	return (read_cpuid_id() & 0xFFF0);
+}
+
 static inline u32 __attribute_const__ read_cpuid_cachetype(void)
 {
 	return read_cpuid(ID_CTR_EL0);