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-rw-r--r--arch/riscv/kvm/tlb.c213
1 files changed, 213 insertions, 0 deletions
diff --git a/arch/riscv/kvm/tlb.c b/arch/riscv/kvm/tlb.c
new file mode 100644
index 000000000000..e2d4fd610745
--- /dev/null
+++ b/arch/riscv/kvm/tlb.c
@@ -0,0 +1,213 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2022 Ventana Micro Systems Inc.
+ */
+
+#include <linux/bitops.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/kvm_host.h>
+#include <asm/csr.h>
+
+/*
+ * Instruction encoding of hfence.gvma is:
+ * HFENCE.GVMA rs1, rs2
+ * HFENCE.GVMA zero, rs2
+ * HFENCE.GVMA rs1
+ * HFENCE.GVMA
+ *
+ * rs1!=zero and rs2!=zero ==> HFENCE.GVMA rs1, rs2
+ * rs1==zero and rs2!=zero ==> HFENCE.GVMA zero, rs2
+ * rs1!=zero and rs2==zero ==> HFENCE.GVMA rs1
+ * rs1==zero and rs2==zero ==> HFENCE.GVMA
+ *
+ * Instruction encoding of HFENCE.GVMA is:
+ * 0110001 rs2(5) rs1(5) 000 00000 1110011
+ */
+
+void kvm_riscv_local_hfence_gvma_vmid_gpa(unsigned long vmid,
+ gpa_t gpa, gpa_t gpsz,
+ unsigned long order)
+{
+ gpa_t pos;
+
+ if (PTRS_PER_PTE < (gpsz >> order)) {
+ kvm_riscv_local_hfence_gvma_vmid_all(vmid);
+ return;
+ }
+
+ for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order)) {
+ /*
+ * rs1 = a0 (GPA >> 2)
+ * rs2 = a1 (VMID)
+ * HFENCE.GVMA a0, a1
+ * 0110001 01011 01010 000 00000 1110011
+ */
+ asm volatile ("srli a0, %0, 2\n"
+ "add a1, %1, zero\n"
+ ".word 0x62b50073\n"
+ :: "r" (pos), "r" (vmid)
+ : "a0", "a1", "memory");
+ }
+}
+
+void kvm_riscv_local_hfence_gvma_vmid_all(unsigned long vmid)
+{
+ /*
+ * rs1 = zero
+ * rs2 = a0 (VMID)
+ * HFENCE.GVMA zero, a0
+ * 0110001 01010 00000 000 00000 1110011
+ */
+ asm volatile ("add a0, %0, zero\n"
+ ".word 0x62a00073\n"
+ :: "r" (vmid) : "a0", "memory");
+}
+
+void kvm_riscv_local_hfence_gvma_gpa(gpa_t gpa, gpa_t gpsz,
+ unsigned long order)
+{
+ gpa_t pos;
+
+ if (PTRS_PER_PTE < (gpsz >> order)) {
+ kvm_riscv_local_hfence_gvma_all();
+ return;
+ }
+
+ for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order)) {
+ /*
+ * rs1 = a0 (GPA >> 2)
+ * rs2 = zero
+ * HFENCE.GVMA a0
+ * 0110001 00000 01010 000 00000 1110011
+ */
+ asm volatile ("srli a0, %0, 2\n"
+ ".word 0x62050073\n"
+ :: "r" (pos) : "a0", "memory");
+ }
+}
+
+void kvm_riscv_local_hfence_gvma_all(void)
+{
+ /*
+ * rs1 = zero
+ * rs2 = zero
+ * HFENCE.GVMA
+ * 0110001 00000 00000 000 00000 1110011
+ */
+ asm volatile (".word 0x62000073" ::: "memory");
+}
+
+/*
+ * Instruction encoding of hfence.gvma is:
+ * HFENCE.VVMA rs1, rs2
+ * HFENCE.VVMA zero, rs2
+ * HFENCE.VVMA rs1
+ * HFENCE.VVMA
+ *
+ * rs1!=zero and rs2!=zero ==> HFENCE.VVMA rs1, rs2
+ * rs1==zero and rs2!=zero ==> HFENCE.VVMA zero, rs2
+ * rs1!=zero and rs2==zero ==> HFENCE.VVMA rs1
+ * rs1==zero and rs2==zero ==> HFENCE.VVMA
+ *
+ * Instruction encoding of HFENCE.VVMA is:
+ * 0010001 rs2(5) rs1(5) 000 00000 1110011
+ */
+
+void kvm_riscv_local_hfence_vvma_asid_gva(unsigned long vmid,
+ unsigned long asid,
+ unsigned long gva,
+ unsigned long gvsz,
+ unsigned long order)
+{
+ unsigned long pos, hgatp;
+
+ if (PTRS_PER_PTE < (gvsz >> order)) {
+ kvm_riscv_local_hfence_vvma_asid_all(vmid, asid);
+ return;
+ }
+
+ hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT);
+
+ for (pos = gva; pos < (gva + gvsz); pos += BIT(order)) {
+ /*
+ * rs1 = a0 (GVA)
+ * rs2 = a1 (ASID)
+ * HFENCE.VVMA a0, a1
+ * 0010001 01011 01010 000 00000 1110011
+ */
+ asm volatile ("add a0, %0, zero\n"
+ "add a1, %1, zero\n"
+ ".word 0x22b50073\n"
+ :: "r" (pos), "r" (asid)
+ : "a0", "a1", "memory");
+ }
+
+ csr_write(CSR_HGATP, hgatp);
+}
+
+void kvm_riscv_local_hfence_vvma_asid_all(unsigned long vmid,
+ unsigned long asid)
+{
+ unsigned long hgatp;
+
+ hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT);
+
+ /*
+ * rs1 = zero
+ * rs2 = a0 (ASID)
+ * HFENCE.VVMA zero, a0
+ * 0010001 01010 00000 000 00000 1110011
+ */
+ asm volatile ("add a0, %0, zero\n"
+ ".word 0x22a00073\n"
+ :: "r" (asid) : "a0", "memory");
+
+ csr_write(CSR_HGATP, hgatp);
+}
+
+void kvm_riscv_local_hfence_vvma_gva(unsigned long vmid,
+ unsigned long gva, unsigned long gvsz,
+ unsigned long order)
+{
+ unsigned long pos, hgatp;
+
+ if (PTRS_PER_PTE < (gvsz >> order)) {
+ kvm_riscv_local_hfence_vvma_all(vmid);
+ return;
+ }
+
+ hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT);
+
+ for (pos = gva; pos < (gva + gvsz); pos += BIT(order)) {
+ /*
+ * rs1 = a0 (GVA)
+ * rs2 = zero
+ * HFENCE.VVMA a0
+ * 0010001 00000 01010 000 00000 1110011
+ */
+ asm volatile ("add a0, %0, zero\n"
+ ".word 0x22050073\n"
+ :: "r" (pos) : "a0", "memory");
+ }
+
+ csr_write(CSR_HGATP, hgatp);
+}
+
+void kvm_riscv_local_hfence_vvma_all(unsigned long vmid)
+{
+ unsigned long hgatp;
+
+ hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT);
+
+ /*
+ * rs1 = zero
+ * rs2 = zero
+ * HFENCE.VVMA
+ * 0010001 00000 00000 000 00000 1110011
+ */
+ asm volatile (".word 0x22000073" ::: "memory");
+
+ csr_write(CSR_HGATP, hgatp);
+}