1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2012-2015 - ARM Ltd 4 * Author: Marc Zyngier <marc.zyngier@arm.com> 5 */ 6 7 #include <hyp/adjust_pc.h> 8 9 #include <linux/compiler.h> 10 #include <linux/irqchip/arm-gic.h> 11 #include <linux/kvm_host.h> 12 #include <linux/swab.h> 13 14 #include <asm/kvm_emulate.h> 15 #include <asm/kvm_hyp.h> 16 #include <asm/kvm_mmu.h> 17 18 static bool __is_be(struct kvm_vcpu *vcpu) 19 { 20 if (vcpu_mode_is_32bit(vcpu)) 21 return !!(read_sysreg_el2(SYS_SPSR) & PSR_AA32_E_BIT); 22 23 return !!(read_sysreg(SCTLR_EL1) & SCTLR_ELx_EE); 24 } 25 26 /* 27 * __vgic_v2_perform_cpuif_access -- perform a GICV access on behalf of the 28 * guest. 29 * 30 * @vcpu: the offending vcpu 31 * 32 * Returns: 33 * 1: GICV access successfully performed 34 * 0: Not a GICV access 35 * -1: Illegal GICV access successfully performed 36 */ 37 int __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu) 38 { 39 struct kvm *kvm = kern_hyp_va(vcpu->kvm); 40 struct vgic_dist *vgic = &kvm->arch.vgic; 41 phys_addr_t fault_ipa; 42 void __iomem *addr; 43 int rd; 44 45 /* Build the full address */ 46 fault_ipa = kvm_vcpu_get_fault_ipa(vcpu); 47 fault_ipa |= kvm_vcpu_get_hfar(vcpu) & GENMASK(11, 0); 48 49 /* If not for GICV, move on */ 50 if (fault_ipa < vgic->vgic_cpu_base || 51 fault_ipa >= (vgic->vgic_cpu_base + KVM_VGIC_V2_CPU_SIZE)) 52 return 0; 53 54 /* Reject anything but a 32bit access */ 55 if (kvm_vcpu_dabt_get_as(vcpu) != sizeof(u32)) { 56 __kvm_skip_instr(vcpu); 57 return -1; 58 } 59 60 /* Not aligned? Don't bother */ 61 if (fault_ipa & 3) { 62 __kvm_skip_instr(vcpu); 63 return -1; 64 } 65 66 rd = kvm_vcpu_dabt_get_rd(vcpu); 67 addr = kvm_vgic_global_state.vcpu_hyp_va; 68 addr += fault_ipa - vgic->vgic_cpu_base; 69 70 if (kvm_vcpu_dabt_iswrite(vcpu)) { 71 u32 data = vcpu_get_reg(vcpu, rd); 72 if (__is_be(vcpu)) { 73 /* guest pre-swabbed data, undo this for writel() */ 74 data = __kvm_swab32(data); 75 } 76 writel_relaxed(data, addr); 77 } else { 78 u32 data = readl_relaxed(addr); 79 if (__is_be(vcpu)) { 80 /* guest expects swabbed data */ 81 data = __kvm_swab32(data); 82 } 83 vcpu_set_reg(vcpu, rd, data); 84 } 85 86 __kvm_skip_instr(vcpu); 87 88 return 1; 89 } 90