1 files changed, 161 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/virt.h b/arch/arm64/include/asm/virt.h
new file mode 100644
index 000000000..261d6e9df
--- /dev/null
+++ b/arch/arm64/include/asm/virt.h
@@ -0,0 +1,161 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ */
+
+#ifndef __ASM__VIRT_H
+#define __ASM__VIRT_H
+
+/*
+ * The arm64 hcall implementation uses x0 to specify the hcall
+ * number. A value less than HVC_STUB_HCALL_NR indicates a special
+ * hcall, such as set vector. Any other value is handled in a
+ * hypervisor specific way.
+ *
+ * The hypercall is allowed to clobber any of the caller-saved
+ * registers (x0-x18), so it is advisable to use it through the
+ * indirection of a function call (as implemented in hyp-stub.S).
+ */
+
+/*
+ * HVC_SET_VECTORS - Set the value of the vbar_el2 register.
+ *
+ * @x1: Physical address of the new vector table.
+ */
+#define HVC_SET_VECTORS 0
+
+/*
+ * HVC_SOFT_RESTART - CPU soft reset, used by the cpu_soft_restart routine.
+ */
+#define HVC_SOFT_RESTART 1
+
+/*
+ * HVC_RESET_VECTORS - Restore the vectors to the original HYP stubs
+ */
+#define HVC_RESET_VECTORS 2
+
+/*
+ * HVC_FINALISE_EL2 - Upgrade the CPU from EL1 to EL2, if possible
+ */
+#define HVC_FINALISE_EL2	3
+
+/* Max number of HYP stub hypercalls */
+#define HVC_STUB_HCALL_NR 4
+
+/* Error returned when an invalid stub number is passed into x0 */
+#define HVC_STUB_ERR	0xbadca11
+
+#define BOOT_CPU_MODE_EL1	(0xe11)
+#define BOOT_CPU_MODE_EL2	(0xe12)
+
+/*
+ * Flags returned together with the boot mode, but not preserved in
+ * __boot_cpu_mode. Used by the idreg override code to work out the
+ * boot state.
+ */
+#define BOOT_CPU_FLAG_E2H	BIT_ULL(32)
+
+#ifndef __ASSEMBLY__
+
+#include <asm/ptrace.h>
+#include <asm/sections.h>
+#include <asm/sysreg.h>
+#include <asm/cpufeature.h>
+
+/*
+ * __boot_cpu_mode records what mode CPUs were booted in.
+ * A correctly-implemented bootloader must start all CPUs in the same mode:
+ * In this case, both 32bit halves of __boot_cpu_mode will contain the
+ * same value (either 0 if booted in EL1, BOOT_CPU_MODE_EL2 if booted in EL2).
+ *
+ * Should the bootloader fail to do this, the two values will be different.
+ * This allows the kernel to flag an error when the secondaries have come up.
+ */
+extern u32 __boot_cpu_mode[2];
+
+#define ARM64_VECTOR_TABLE_LEN	SZ_2K
+
+void __hyp_set_vectors(phys_addr_t phys_vector_base);
+void __hyp_reset_vectors(void);
+bool is_kvm_arm_initialised(void);
+
+DECLARE_STATIC_KEY_FALSE(kvm_protected_mode_initialized);
+
+/* Reports the availability of HYP mode */
+static inline bool is_hyp_mode_available(void)
+{
+	/*
+	 * If KVM protected mode is initialized, all CPUs must have been booted
+	 * in EL2. Avoid checking __boot_cpu_mode as CPUs now come up in EL1.
+	 */
+	if (IS_ENABLED(CONFIG_KVM) &&
+	    static_branch_likely(&kvm_protected_mode_initialized))
+		return true;
+
+	return (__boot_cpu_mode[0] == BOOT_CPU_MODE_EL2 &&
+		__boot_cpu_mode[1] == BOOT_CPU_MODE_EL2);
+}
+
+/* Check if the bootloader has booted CPUs in different modes */
+static inline bool is_hyp_mode_mismatched(void)
+{
+	/*
+	 * If KVM protected mode is initialized, all CPUs must have been booted
+	 * in EL2. Avoid checking __boot_cpu_mode as CPUs now come up in EL1.
+	 */
+	if (IS_ENABLED(CONFIG_KVM) &&
+	    static_branch_likely(&kvm_protected_mode_initialized))
+		return false;
+
+	return __boot_cpu_mode[0] != __boot_cpu_mode[1];
+}
+
+static __always_inline bool is_kernel_in_hyp_mode(void)
+{
+	BUILD_BUG_ON(__is_defined(__KVM_NVHE_HYPERVISOR__) ||
+		     __is_defined(__KVM_VHE_HYPERVISOR__));
+	return read_sysreg(CurrentEL) == CurrentEL_EL2;
+}
+
+static __always_inline bool has_vhe(void)
+{
+	/*
+	 * Code only run in VHE/NVHE hyp context can assume VHE is present or
+	 * absent. Otherwise fall back to caps.
+	 * This allows the compiler to discard VHE-specific code from the
+	 * nVHE object, reducing the number of external symbol references
+	 * needed to link.
+	 */
+	if (is_vhe_hyp_code())
+		return true;
+	else if (is_nvhe_hyp_code())
+		return false;
+	else
+		return cpus_have_final_cap(ARM64_HAS_VIRT_HOST_EXTN);
+}
+
+static __always_inline bool is_protected_kvm_enabled(void)
+{
+	if (is_vhe_hyp_code())
+		return false;
+	else
+		return cpus_have_final_cap(ARM64_KVM_PROTECTED_MODE);
+}
+
+static __always_inline bool has_hvhe(void)
+{
+	if (is_vhe_hyp_code())
+		return false;
+
+	return cpus_have_final_cap(ARM64_KVM_HVHE);
+}
+
+static inline bool is_hyp_nvhe(void)
+{
+	return is_hyp_mode_available() && !is_kernel_in_hyp_mode();
+}
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* ! __ASM__VIRT_H */