lib: Add hfence instruction encoding

Currently, the toolchains do not have support for hfence instruction.
Hence, the instruction are hardcode until we have toolchain support.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

include/sbi/sbi_hfence.h

@@ -0,0 +1,36 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2019 Western Digital Corporation or its affiliates.
+ *
+ * Authors:
+ *   Atish Patra <atish.patra@wdc.com>
+ *   Anup Patel <anup.patel@wdc.com>
+ */
+
+#ifndef __SBI_FENCE_H__
+#define __SBI_FENCE_H__
+/** Invalidate Stage2 TLBs for given VMID and guest physical address */
+void __sbi_hfence_gvma_vmid_gpa(unsigned long vmid, unsigned long gpa);
+
+/** Invalidate Stage2 TLBs for given VMID */
+void __sbi_hfence_gvma_vmid(unsigned long vmid);
+
+/** Invalidate Stage2 TLBs for given guest physical address */
+void __sbi_hfence_gvma_gpa(unsigned long gpa);
+
+/** Invalidate all possible Stage2 TLBs */
+void __sbi_hfence_gvma_all(void);
+
+/** Invalidate unified TLB entries for given asid and guest virtual address */
+void __sbi_hfence_vvma_asid_va(unsigned long asid, unsigned long va);
+
+/** Invalidate unified TLB entries for given ASID for a guest*/
+void __sbi_hfence_vvma_asid(unsigned long asid);
+
+/** Invalidate unified TLB entries for a given guest virtual address */
+void __sbi_hfence_vvma_va(unsigned long va);
+
+/** Invalidate all possible Stage2 TLBs */
+void __sbi_hfence_vvma_all(void);
+#endif

lib/sbi/objects.mk

@@ -16,6 +16,7 @@ libsbi-objs-y += sbi_console.o
 libsbi-objs-y += sbi_ecall.o
 libsbi-objs-y += sbi_emulate_csr.o
 libsbi-objs-y += sbi_fifo.o
+libsbi-objs-y += sbi_hfence.o
 libsbi-objs-y += sbi_hart.o
 libsbi-objs-y += sbi_illegal_insn.o
 libsbi-objs-y += sbi_init.o

lib/sbi/sbi_hfence.S

@@ -0,0 +1,75 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2019 Western Digital Corporation or its affiliates.
+ *
+ * Authors:
+ *   Anup Patel <anup.patel@wdc.com>
+ *   Atish Patra <anup.patel@wdc.com>
+ */
+
+	/*
+	 * Instruction encoding of hfence.gvma is:
+	 * 0110001 rs2(5) rs1(5) 000 00000 1110011
+	 */
+
+	.align 3
+	.global __sbi_hfence_gvma_vmid_gpa
+__sbi_hfence_gvma_vmid_gpa:
+	/* hfence.gvma a1, a0 */
+	.word 0x62a60073
+	ret
+
+	.align 3
+	.global __sbi_hfence_gvma_vmid
+__sbi_hfence_gvma_vmid:
+	/* hfence.gvma zero, a0 */
+	.word 0x62a00073
+	ret
+
+	.align 3
+	.global __sbi_hfence_gvma_gpa
+__sbi_hfence_gvma_gpa:
+	/* hfence.gvma a0 */
+	.word 0x62050073
+	ret
+
+	.align 3
+	.global __sbi_hfence_gvma_all
+__sbi_hfence_gvma_all:
+	/* hfence.gvma */
+	.word 0x62000073
+	ret
+
+	/*
+	 * Instruction encoding of hfence.bvma is:
+	 * 0010001 rs2(5) rs1(5) 000 00000 1110011
+	 */
+
+	.align 3
+	.global __sbi_hfence_vvma_asid_va
+__sbi_hfence_vvma_asid_va:
+	/* hfence.bvma a1, a0 */
+	.word 0x22a60073
+	ret
+
+	.align 3
+	.global __sbi_hfence_vvma_asid
+__sbi_hfence_vvma_asid:
+	/* hfence.bvma zero, a0 */
+	.word 0x22a00073
+	ret
+
+	.align 3
+	.global __sbi_hfence_vvma_va
+__sbi_hfence_vvma_va:
+	/* hfence.bvma a0 */
+	.word 0x22050073
+	ret
+
+	.align 3
+	.global __sbi_hfence_vvma_all
+__sbi_hfence_vvma_all:
+	/* hfence.bvma */
+	.word 0x22000073
+	ret