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 #include <asm/hwcap.h> 15 16 #ifdef CONFIG_FPU 17 void kvm_riscv_vcpu_fp_reset(struct kvm_vcpu *vcpu) 18 { 19 struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; 20 21 cntx->sstatus &= ~SR_FS; 22 if (riscv_isa_extension_available(vcpu->arch.isa, f) || 23 riscv_isa_extension_available(vcpu->arch.isa, d)) 24 cntx->sstatus |= SR_FS_INITIAL; 25 else 26 cntx->sstatus |= SR_FS_OFF; 27 } 28 29 static 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 const 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 const 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 __user *uaddr = 83 (unsigned long __user *)(unsigned long)reg->addr; 84 unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | 85 KVM_REG_SIZE_MASK | 86 rtype); 87 void *reg_val; 88 89 if ((rtype == KVM_REG_RISCV_FP_F) && 90 riscv_isa_extension_available(vcpu->arch.isa, f)) { 91 if (KVM_REG_SIZE(reg->id) != sizeof(u32)) 92 return -EINVAL; 93 if (reg_num == KVM_REG_RISCV_FP_F_REG(fcsr)) 94 reg_val = &cntx->fp.f.fcsr; 95 else if ((KVM_REG_RISCV_FP_F_REG(f[0]) <= reg_num) && 96 reg_num <= KVM_REG_RISCV_FP_F_REG(f[31])) 97 reg_val = &cntx->fp.f.f[reg_num]; 98 else 99 return -EINVAL; 100 } else if ((rtype == KVM_REG_RISCV_FP_D) && 101 riscv_isa_extension_available(vcpu->arch.isa, d)) { 102 if (reg_num == KVM_REG_RISCV_FP_D_REG(fcsr)) { 103 if (KVM_REG_SIZE(reg->id) != sizeof(u32)) 104 return -EINVAL; 105 reg_val = &cntx->fp.d.fcsr; 106 } else if ((KVM_REG_RISCV_FP_D_REG(f[0]) <= reg_num) && 107 reg_num <= KVM_REG_RISCV_FP_D_REG(f[31])) { 108 if (KVM_REG_SIZE(reg->id) != sizeof(u64)) 109 return -EINVAL; 110 reg_val = &cntx->fp.d.f[reg_num]; 111 } else 112 return -EINVAL; 113 } else 114 return -EINVAL; 115 116 if (copy_to_user(uaddr, reg_val, KVM_REG_SIZE(reg->id))) 117 return -EFAULT; 118 119 return 0; 120 } 121 122 int kvm_riscv_vcpu_set_reg_fp(struct kvm_vcpu *vcpu, 123 const struct kvm_one_reg *reg, 124 unsigned long rtype) 125 { 126 struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; 127 unsigned long __user *uaddr = 128 (unsigned long __user *)(unsigned long)reg->addr; 129 unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | 130 KVM_REG_SIZE_MASK | 131 rtype); 132 void *reg_val; 133 134 if ((rtype == KVM_REG_RISCV_FP_F) && 135 riscv_isa_extension_available(vcpu->arch.isa, f)) { 136 if (KVM_REG_SIZE(reg->id) != sizeof(u32)) 137 return -EINVAL; 138 if (reg_num == KVM_REG_RISCV_FP_F_REG(fcsr)) 139 reg_val = &cntx->fp.f.fcsr; 140 else if ((KVM_REG_RISCV_FP_F_REG(f[0]) <= reg_num) && 141 reg_num <= KVM_REG_RISCV_FP_F_REG(f[31])) 142 reg_val = &cntx->fp.f.f[reg_num]; 143 else 144 return -EINVAL; 145 } else if ((rtype == KVM_REG_RISCV_FP_D) && 146 riscv_isa_extension_available(vcpu->arch.isa, d)) { 147 if (reg_num == KVM_REG_RISCV_FP_D_REG(fcsr)) { 148 if (KVM_REG_SIZE(reg->id) != sizeof(u32)) 149 return -EINVAL; 150 reg_val = &cntx->fp.d.fcsr; 151 } else if ((KVM_REG_RISCV_FP_D_REG(f[0]) <= reg_num) && 152 reg_num <= KVM_REG_RISCV_FP_D_REG(f[31])) { 153 if (KVM_REG_SIZE(reg->id) != sizeof(u64)) 154 return -EINVAL; 155 reg_val = &cntx->fp.d.f[reg_num]; 156 } else 157 return -EINVAL; 158 } else 159 return -EINVAL; 160 161 if (copy_from_user(reg_val, uaddr, KVM_REG_SIZE(reg->id))) 162 return -EFAULT; 163 164 return 0; 165 } 166