1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2021 Western Digital Corporation or its affiliates. 4 * 5 * Authors: 6 * Atish Patra <atish.patra@wdc.com> 7 */ 8 9 #include <linux/errno.h> 10 #include <linux/err.h> 11 #include <linux/kvm_host.h> 12 #include <linux/version.h> 13 #include <asm/csr.h> 14 #include <asm/sbi.h> 15 #include <asm/kvm_vcpu_timer.h> 16 #include <asm/kvm_vcpu_sbi.h> 17 18 static int kvm_sbi_ext_base_handler(struct kvm_vcpu *vcpu, struct kvm_run *run, 19 unsigned long *out_val, 20 struct kvm_cpu_trap *trap, bool *exit) 21 { 22 int ret = 0; 23 struct kvm_cpu_context *cp = &vcpu->arch.guest_context; 24 struct sbiret ecall_ret; 25 26 switch (cp->a6) { 27 case SBI_EXT_BASE_GET_SPEC_VERSION: 28 *out_val = (KVM_SBI_VERSION_MAJOR << 29 SBI_SPEC_VERSION_MAJOR_SHIFT) | 30 KVM_SBI_VERSION_MINOR; 31 break; 32 case SBI_EXT_BASE_GET_IMP_ID: 33 *out_val = KVM_SBI_IMPID; 34 break; 35 case SBI_EXT_BASE_GET_IMP_VERSION: 36 *out_val = LINUX_VERSION_CODE; 37 break; 38 case SBI_EXT_BASE_PROBE_EXT: 39 if ((cp->a0 >= SBI_EXT_EXPERIMENTAL_START && 40 cp->a0 <= SBI_EXT_EXPERIMENTAL_END) || 41 (cp->a0 >= SBI_EXT_VENDOR_START && 42 cp->a0 <= SBI_EXT_VENDOR_END)) { 43 /* 44 * For experimental/vendor extensions 45 * forward it to the userspace 46 */ 47 kvm_riscv_vcpu_sbi_forward(vcpu, run); 48 *exit = true; 49 } else 50 *out_val = kvm_vcpu_sbi_find_ext(cp->a0) ? 1 : 0; 51 break; 52 case SBI_EXT_BASE_GET_MVENDORID: 53 case SBI_EXT_BASE_GET_MARCHID: 54 case SBI_EXT_BASE_GET_MIMPID: 55 ecall_ret = sbi_ecall(SBI_EXT_BASE, cp->a6, 0, 0, 0, 0, 0, 0); 56 if (!ecall_ret.error) 57 *out_val = ecall_ret.value; 58 /*TODO: We are unnecessarily converting the error twice */ 59 ret = sbi_err_map_linux_errno(ecall_ret.error); 60 break; 61 default: 62 ret = -EOPNOTSUPP; 63 break; 64 } 65 66 return ret; 67 } 68 69 const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_base = { 70 .extid_start = SBI_EXT_BASE, 71 .extid_end = SBI_EXT_BASE, 72 .handler = kvm_sbi_ext_base_handler, 73 }; 74 75 static int kvm_sbi_ext_forward_handler(struct kvm_vcpu *vcpu, 76 struct kvm_run *run, 77 unsigned long *out_val, 78 struct kvm_cpu_trap *utrap, 79 bool *exit) 80 { 81 /* 82 * Both SBI experimental and vendor extensions are 83 * unconditionally forwarded to userspace. 84 */ 85 kvm_riscv_vcpu_sbi_forward(vcpu, run); 86 *exit = true; 87 return 0; 88 } 89 90 const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_experimental = { 91 .extid_start = SBI_EXT_EXPERIMENTAL_START, 92 .extid_end = SBI_EXT_EXPERIMENTAL_END, 93 .handler = kvm_sbi_ext_forward_handler, 94 }; 95 96 const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_vendor = { 97 .extid_start = SBI_EXT_VENDOR_START, 98 .extid_end = SBI_EXT_VENDOR_END, 99 .handler = kvm_sbi_ext_forward_handler, 100 }; 101