1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2019 Western Digital Corporation or its affiliates. 4 * 5 * Authors: 6 * Anup Patel <anup.patel@wdc.com> 7 */ 8 9 #include <linux/errno.h> 10 #include <linux/err.h> 11 #include <linux/module.h> 12 #include <linux/kvm_host.h> 13 #include <asm/csr.h> 14 #include <asm/hwcap.h> 15 #include <asm/sbi.h> 16 17 long kvm_arch_dev_ioctl(struct file *filp, 18 unsigned int ioctl, unsigned long arg) 19 { 20 return -EINVAL; 21 } 22 23 int kvm_arch_hardware_enable(void) 24 { 25 unsigned long hideleg, hedeleg; 26 27 hedeleg = 0; 28 hedeleg |= (1UL << EXC_INST_MISALIGNED); 29 hedeleg |= (1UL << EXC_BREAKPOINT); 30 hedeleg |= (1UL << EXC_SYSCALL); 31 hedeleg |= (1UL << EXC_INST_PAGE_FAULT); 32 hedeleg |= (1UL << EXC_LOAD_PAGE_FAULT); 33 hedeleg |= (1UL << EXC_STORE_PAGE_FAULT); 34 csr_write(CSR_HEDELEG, hedeleg); 35 36 hideleg = 0; 37 hideleg |= (1UL << IRQ_VS_SOFT); 38 hideleg |= (1UL << IRQ_VS_TIMER); 39 hideleg |= (1UL << IRQ_VS_EXT); 40 csr_write(CSR_HIDELEG, hideleg); 41 42 /* VS should access only the time counter directly. Everything else should trap */ 43 csr_write(CSR_HCOUNTEREN, 0x02); 44 45 csr_write(CSR_HVIP, 0); 46 47 return 0; 48 } 49 50 void kvm_arch_hardware_disable(void) 51 { 52 /* 53 * After clearing the hideleg CSR, the host kernel will receive 54 * spurious interrupts if hvip CSR has pending interrupts and the 55 * corresponding enable bits in vsie CSR are asserted. To avoid it, 56 * hvip CSR and vsie CSR must be cleared before clearing hideleg CSR. 57 */ 58 csr_write(CSR_VSIE, 0); 59 csr_write(CSR_HVIP, 0); 60 csr_write(CSR_HEDELEG, 0); 61 csr_write(CSR_HIDELEG, 0); 62 } 63 64 static int __init riscv_kvm_init(void) 65 { 66 const char *str; 67 68 if (!riscv_isa_extension_available(NULL, h)) { 69 kvm_info("hypervisor extension not available\n"); 70 return -ENODEV; 71 } 72 73 if (sbi_spec_is_0_1()) { 74 kvm_info("require SBI v0.2 or higher\n"); 75 return -ENODEV; 76 } 77 78 if (sbi_probe_extension(SBI_EXT_RFENCE) <= 0) { 79 kvm_info("require SBI RFENCE extension\n"); 80 return -ENODEV; 81 } 82 83 kvm_riscv_gstage_mode_detect(); 84 85 kvm_riscv_gstage_vmid_detect(); 86 87 kvm_info("hypervisor extension available\n"); 88 89 switch (kvm_riscv_gstage_mode()) { 90 case HGATP_MODE_SV32X4: 91 str = "Sv32x4"; 92 break; 93 case HGATP_MODE_SV39X4: 94 str = "Sv39x4"; 95 break; 96 case HGATP_MODE_SV48X4: 97 str = "Sv48x4"; 98 break; 99 case HGATP_MODE_SV57X4: 100 str = "Sv57x4"; 101 break; 102 default: 103 return -ENODEV; 104 } 105 kvm_info("using %s G-stage page table format\n", str); 106 107 kvm_info("VMID %ld bits available\n", kvm_riscv_gstage_vmid_bits()); 108 109 return kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE); 110 } 111 module_init(riscv_kvm_init); 112 113 static void __exit riscv_kvm_exit(void) 114 { 115 kvm_exit(); 116 } 117 module_exit(riscv_kvm_exit); 118