[PATCH 3/6] KVM: LoongArch: selftests: Add basic interfaces

[Bibo Mao]

Add some basic function interfaces such as CSR register access,
local irq enable or disable APIs.

Signed-off-by: Bibo Mao <maob...@loongson.cn>
---
 .../kvm/include/loongarch/processor.h         | 52 +++++++++++++++++++
 .../selftests/kvm/lib/loongarch/processor.c   |  5 ++
 2 files changed, 57 insertions(+)

diff --git a/tools/testing/selftests/kvm/include/loongarch/processor.h 
b/tools/testing/selftests/kvm/include/loongarch/processor.h
index a18ac7bff303..b027f8f4dac7 100644
--- a/tools/testing/selftests/kvm/include/loongarch/processor.h
+++ b/tools/testing/selftests/kvm/include/loongarch/processor.h
@@ -118,6 +118,28 @@
 #define  CSR_TLBREHI_PS_SHIFT          0
 #define  CSR_TLBREHI_PS                        (0x3fUL << CSR_TLBREHI_PS_SHIFT)
 
+#define csr_read(csr)                          \
+({                                             \
+       register unsigned long __v;             \
+       __asm__ __volatile__(                   \
+               "csrrd %[val], %[reg]\n\t"      \
+               : [val] "=r" (__v)              \
+               : [reg] "i" (csr)               \
+               : "memory");                    \
+       __v;                                    \
+})
+
+#define csr_write(v, csr)                      \
+({                                             \
+       register unsigned long __v = v;         \
+       __asm__ __volatile__ (                  \
+               "csrwr %[val], %[reg]\n\t"      \
+               : [val] "+r" (__v)              \
+               : [reg] "i" (csr)               \
+               : "memory");                    \
+       __v;                                    \
+})
+
 #define EXREGS_GPRS                    (32)
 
 #ifndef __ASSEMBLER__
@@ -147,6 +169,36 @@ struct handlers {
 void vm_init_descriptor_tables(struct kvm_vm *vm);
 void vm_install_exception_handler(struct kvm_vm *vm, int vector, handler_fn 
handler);
 
+static inline void local_irq_enable(void)
+{
+       unsigned int flags = CSR_CRMD_IE;
+
+       register unsigned int mask asm("$t0") = CSR_CRMD_IE;
+
+       __asm__ __volatile__(
+               "csrxchg %[val], %[mask], %[reg]\n\t"
+               : [val] "+r" (flags)
+               : [mask] "r" (mask), [reg] "i" (LOONGARCH_CSR_CRMD)
+               : "memory");
+}
+
+static inline void local_irq_disable(void)
+{
+       unsigned int flags = 0;
+
+       register unsigned int mask asm("$t0") = CSR_CRMD_IE;
+
+       __asm__ __volatile__(
+               "csrxchg %[val], %[mask], %[reg]\n\t"
+               : [val] "+r" (flags)
+               : [mask] "r" (mask), [reg] "i" (LOONGARCH_CSR_CRMD)
+               : "memory");
+}
+
+static inline void cpu_relax(void)
+{
+       asm volatile("nop" ::: "memory");
+}
 #else
 #define PC_OFFSET_EXREGS               ((EXREGS_GPRS + 0) * 8)
 #define ESTAT_OFFSET_EXREGS            ((EXREGS_GPRS + 1) * 8)
diff --git a/tools/testing/selftests/kvm/lib/loongarch/processor.c 
b/tools/testing/selftests/kvm/lib/loongarch/processor.c
index be537c5ff74e..20ba476ccb72 100644
--- a/tools/testing/selftests/kvm/lib/loongarch/processor.c
+++ b/tools/testing/selftests/kvm/lib/loongarch/processor.c
@@ -373,3 +373,8 @@ void vcpu_arch_set_entry_point(struct kvm_vcpu *vcpu, void 
*guest_code)
        regs.pc = (uint64_t)guest_code;
        vcpu_regs_set(vcpu, &regs);
 }
+
+uint32_t guest_get_vcpuid(void)
+{
+       return csr_read(LOONGARCH_CSR_CPUID);
+}
-- 
2.39.3