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 * Anup Patel <anup.patel@wdc.com> 8 */ 9 10 #include <linux/errno.h> 11 #include <linux/err.h> 12 #include <linux/kvm_host.h> 13 #include <linux/uaccess.h> 14 15 #ifdef CONFIG_FPU 16 void kvm_riscv_vcpu_fp_reset(struct kvm_vcpu *vcpu) 17 { 18 unsigned long isa = vcpu->arch.isa; 19 struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; 20 21 cntx->sstatus &= ~SR_FS; 22 if (riscv_isa_extension_available(&isa, f) || 23 riscv_isa_extension_available(&isa, d)) 24 cntx->sstatus |= SR_FS_INITIAL; 25 else 26 cntx->sstatus |= SR_FS_OFF; 27 } 28 29 void kvm_riscv_vcpu_fp_clean(struct kvm_cpu_context *cntx) 30 { 31 cntx->sstatus &= ~SR_FS; 32 cntx->sstatus |= SR_FS_CLEAN; 33 } 34 35 void kvm_riscv_vcpu_guest_fp_save(struct kvm_cpu_context *cntx, 36 unsigned long isa) 37 { 38 if ((cntx->sstatus & SR_FS) == SR_FS_DIRTY) { 39 if (riscv_isa_extension_available(&isa, d)) 40 __kvm_riscv_fp_d_save(cntx); 41 else if (riscv_isa_extension_available(&isa, f)) 42 __kvm_riscv_fp_f_save(cntx); 43 kvm_riscv_vcpu_fp_clean(cntx); 44 } 45 } 46 47 void kvm_riscv_vcpu_guest_fp_restore(struct kvm_cpu_context *cntx, 48 unsigned long isa) 49 { 50 if ((cntx->sstatus & SR_FS) != SR_FS_OFF) { 51 if (riscv_isa_extension_available(&isa, d)) 52 __kvm_riscv_fp_d_restore(cntx); 53 else if (riscv_isa_extension_available(&isa, f)) 54 __kvm_riscv_fp_f_restore(cntx); 55 kvm_riscv_vcpu_fp_clean(cntx); 56 } 57 } 58 59 void kvm_riscv_vcpu_host_fp_save(struct kvm_cpu_context *cntx) 60 { 61 /* No need to check host sstatus as it can be modified outside */ 62 if (riscv_isa_extension_available(NULL, d)) 63 __kvm_riscv_fp_d_save(cntx); 64 else if (riscv_isa_extension_available(NULL, f)) 65 __kvm_riscv_fp_f_save(cntx); 66 } 67 68 void kvm_riscv_vcpu_host_fp_restore(struct kvm_cpu_context *cntx) 69 { 70 if (riscv_isa_extension_available(NULL, d)) 71 __kvm_riscv_fp_d_restore(cntx); 72 else if (riscv_isa_extension_available(NULL, f)) 73 __kvm_riscv_fp_f_restore(cntx); 74 } 75 #endif 76 77 int kvm_riscv_vcpu_get_reg_fp(struct kvm_vcpu *vcpu, 78 const struct kvm_one_reg *reg, 79 unsigned long rtype) 80 { 81 struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; 82 unsigned long isa = vcpu->arch.isa; 83 unsigned long __user *uaddr = 84 (unsigned long __user *)(unsigned long)reg->addr; 85 unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | 86 KVM_REG_SIZE_MASK | 87 rtype); 88 void *reg_val; 89 90 if ((rtype == KVM_REG_RISCV_FP_F) && 91 riscv_isa_extension_available(&isa, f)) { 92 if (KVM_REG_SIZE(reg->id) != sizeof(u32)) 93 return -EINVAL; 94 if (reg_num == KVM_REG_RISCV_FP_F_REG(fcsr)) 95 reg_val = &cntx->fp.f.fcsr; 96 else if ((KVM_REG_RISCV_FP_F_REG(f[0]) <= reg_num) && 97 reg_num <= KVM_REG_RISCV_FP_F_REG(f[31])) 98 reg_val = &cntx->fp.f.f[reg_num]; 99 else 100 return -EINVAL; 101 } else if ((rtype == KVM_REG_RISCV_FP_D) && 102 riscv_isa_extension_available(&isa, d)) { 103 if (reg_num == KVM_REG_RISCV_FP_D_REG(fcsr)) { 104 if (KVM_REG_SIZE(reg->id) != sizeof(u32)) 105 return -EINVAL; 106 reg_val = &cntx->fp.d.fcsr; 107 } else if ((KVM_REG_RISCV_FP_D_REG(f[0]) <= reg_num) && 108 reg_num <= KVM_REG_RISCV_FP_D_REG(f[31])) { 109 if (KVM_REG_SIZE(reg->id) != sizeof(u64)) 110 return -EINVAL; 111 reg_val = &cntx->fp.d.f[reg_num]; 112 } else 113 return -EINVAL; 114 } else 115 return -EINVAL; 116 117 if (copy_to_user(uaddr, reg_val, KVM_REG_SIZE(reg->id))) 118 return -EFAULT; 119 120 return 0; 121 } 122 123 int kvm_riscv_vcpu_set_reg_fp(struct kvm_vcpu *vcpu, 124 const struct kvm_one_reg *reg, 125 unsigned long rtype) 126 { 127 struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; 128 unsigned long isa = vcpu->arch.isa; 129 unsigned long __user *uaddr = 130 (unsigned long __user *)(unsigned long)reg->addr; 131 unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | 132 KVM_REG_SIZE_MASK | 133 rtype); 134 void *reg_val; 135 136 if ((rtype == KVM_REG_RISCV_FP_F) && 137 riscv_isa_extension_available(&isa, f)) { 138 if (KVM_REG_SIZE(reg->id) != sizeof(u32)) 139 return -EINVAL; 140 if (reg_num == KVM_REG_RISCV_FP_F_REG(fcsr)) 141 reg_val = &cntx->fp.f.fcsr; 142 else if ((KVM_REG_RISCV_FP_F_REG(f[0]) <= reg_num) && 143 reg_num <= KVM_REG_RISCV_FP_F_REG(f[31])) 144 reg_val = &cntx->fp.f.f[reg_num]; 145 else 146 return -EINVAL; 147 } else if ((rtype == KVM_REG_RISCV_FP_D) && 148 riscv_isa_extension_available(&isa, d)) { 149 if (reg_num == KVM_REG_RISCV_FP_D_REG(fcsr)) { 150 if (KVM_REG_SIZE(reg->id) != sizeof(u32)) 151 return -EINVAL; 152 reg_val = &cntx->fp.d.fcsr; 153 } else if ((KVM_REG_RISCV_FP_D_REG(f[0]) <= reg_num) && 154 reg_num <= KVM_REG_RISCV_FP_D_REG(f[31])) { 155 if (KVM_REG_SIZE(reg->id) != sizeof(u64)) 156 return -EINVAL; 157 reg_val = &cntx->fp.d.f[reg_num]; 158 } else 159 return -EINVAL; 160 } else 161 return -EINVAL; 162 163 if (copy_from_user(reg_val, uaddr, KVM_REG_SIZE(reg->id))) 164 return -EFAULT; 165 166 return 0; 167 } 168