From 1a89dd9113badd7487313410a5f2e09b2944f92b Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 21 Jan 2013 19:36:12 -0500 Subject: [PATCH] ARM: KVM: Initial VGIC infrastructure code Wire the basic framework code for VGIC support and the initial in-kernel MMIO support code for the VGIC, used for the distributor emulation. Reviewed-by: Will Deacon Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm/include/asm/kvm_host.h | 8 ++ arch/arm/include/asm/kvm_vgic.h | 80 +++++++++++++++++ arch/arm/kvm/Makefile | 1 + arch/arm/kvm/arm.c | 27 +++++- arch/arm/kvm/interrupts.S | 4 + arch/arm/kvm/mmio.c | 3 + arch/arm/kvm/vgic.c | 153 ++++++++++++++++++++++++++++++++ 7 files changed, 275 insertions(+), 1 deletion(-) create mode 100644 arch/arm/include/asm/kvm_vgic.h create mode 100644 arch/arm/kvm/vgic.c diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index fc161de21ea2..6791c888b9f4 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -37,6 +37,8 @@ #define KVM_NR_PAGE_SIZES 1 #define KVM_PAGES_PER_HPAGE(x) (1UL<<31) +#include + struct kvm_vcpu; u32 *kvm_vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num, u32 mode); int kvm_target_cpu(void); @@ -58,6 +60,9 @@ struct kvm_arch { /* Stage-2 page table */ pgd_t *pgd; + + /* Interrupt controller */ + struct vgic_dist vgic; }; #define KVM_NR_MEM_OBJS 40 @@ -92,6 +97,9 @@ struct kvm_vcpu_arch { struct vfp_hard_struct vfp_guest; struct vfp_hard_struct *vfp_host; + /* VGIC state */ + struct vgic_cpu vgic_cpu; + /* * Anything that is not used directly from assembly code goes * here. diff --git a/arch/arm/include/asm/kvm_vgic.h b/arch/arm/include/asm/kvm_vgic.h new file mode 100644 index 000000000000..8f44799b8db1 --- /dev/null +++ b/arch/arm/include/asm/kvm_vgic.h @@ -0,0 +1,80 @@ +/* + * Copyright (C) 2012 ARM Ltd. + * Author: Marc Zyngier + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#ifndef __ASM_ARM_KVM_VGIC_H +#define __ASM_ARM_KVM_VGIC_H + +#include + +struct vgic_dist { +}; + +struct vgic_cpu { +}; + +struct kvm; +struct kvm_vcpu; +struct kvm_run; +struct kvm_exit_mmio; + +#ifdef CONFIG_KVM_ARM_VGIC +bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run, + struct kvm_exit_mmio *mmio); + +#else +static inline int kvm_vgic_hyp_init(void) +{ + return 0; +} + +static inline int kvm_vgic_init(struct kvm *kvm) +{ + return 0; +} + +static inline int kvm_vgic_create(struct kvm *kvm) +{ + return 0; +} + +static inline int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu) +{ + return 0; +} + +static inline void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu) {} +static inline void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu) {} + +static inline int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu) +{ + return 0; +} + +static inline bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run, + struct kvm_exit_mmio *mmio) +{ + return false; +} + +static inline int irqchip_in_kernel(struct kvm *kvm) +{ + return 0; +} +#endif + +#endif diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile index ea27987bd07f..dece8edc2e4a 100644 --- a/arch/arm/kvm/Makefile +++ b/arch/arm/kvm/Makefile @@ -19,3 +19,4 @@ kvm-arm-y = $(addprefix ../../../virt/kvm/, kvm_main.o coalesced_mmio.o) obj-y += kvm-arm.o init.o interrupts.o obj-y += arm.o guest.o mmu.o emulate.o reset.o obj-y += coproc.o coproc_a15.o mmio.o psci.o +obj-$(CONFIG_KVM_ARM_VGIC) += vgic.o diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 0cf144f95945..7305aef28d0e 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -62,6 +62,8 @@ static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1); static u8 kvm_next_vmid; static DEFINE_SPINLOCK(kvm_vmid_lock); +static bool vgic_present; + static void kvm_arm_set_running_vcpu(struct kvm_vcpu *vcpu) { BUG_ON(preemptible()); @@ -184,6 +186,9 @@ int kvm_dev_ioctl_check_extension(long ext) { int r; switch (ext) { + case KVM_CAP_IRQCHIP: + r = vgic_present; + break; case KVM_CAP_USER_MEMORY: case KVM_CAP_SYNC_MMU: case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: @@ -315,8 +320,16 @@ int __attribute_const__ kvm_target_cpu(void) int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) { + int ret; + /* Force users to call KVM_ARM_VCPU_INIT */ vcpu->arch.target = -1; + + /* Set up VGIC */ + ret = kvm_vgic_vcpu_init(vcpu); + if (ret) + return ret; + return 0; } @@ -374,7 +387,7 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, */ int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) { - return !!v->arch.irq_lines; + return !!v->arch.irq_lines || kvm_vgic_vcpu_pending_irq(v); } /* Just ensure a guest exit from a particular CPU */ @@ -693,6 +706,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) if (vcpu->arch.pause) vcpu_pause(vcpu); + kvm_vgic_flush_hwstate(vcpu); + local_irq_disable(); /* @@ -705,6 +720,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) if (ret <= 0 || need_new_vmid_gen(vcpu->kvm)) { local_irq_enable(); + kvm_vgic_sync_hwstate(vcpu); continue; } @@ -737,6 +753,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) * Back from guest *************************************************************/ + kvm_vgic_sync_hwstate(vcpu); + ret = handle_exit(vcpu, run, ret); } @@ -1011,6 +1029,13 @@ static int init_hyp_mode(void) } } + /* + * Init HYP view of VGIC + */ + err = kvm_vgic_hyp_init(); + if (err) + goto out_free_vfp; + kvm_info("Hyp mode initialized successfully\n"); return 0; out_free_vfp: diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S index c5400d2e97ca..5f113bedfaee 100644 --- a/arch/arm/kvm/interrupts.S +++ b/arch/arm/kvm/interrupts.S @@ -94,6 +94,8 @@ ENTRY(__kvm_vcpu_run) save_host_regs + restore_vgic_state + @ Store hardware CP15 state and load guest state read_cp15_state store_to_vcpu = 0 write_cp15_state read_from_vcpu = 1 @@ -187,6 +189,8 @@ after_vfp_restore: read_cp15_state store_to_vcpu = 1 write_cp15_state read_from_vcpu = 0 + save_vgic_state + restore_host_regs clrex @ Clear exclusive monitor mov r0, r1 @ Return the return code diff --git a/arch/arm/kvm/mmio.c b/arch/arm/kvm/mmio.c index 0144baf82904..98a870ff1a5c 100644 --- a/arch/arm/kvm/mmio.c +++ b/arch/arm/kvm/mmio.c @@ -148,6 +148,9 @@ int io_mem_abort(struct kvm_vcpu *vcpu, struct kvm_run *run, if (mmio.is_write) memcpy(mmio.data, vcpu_reg(vcpu, rt), mmio.len); + if (vgic_handle_mmio(vcpu, run, &mmio)) + return 1; + kvm_prepare_mmio(run, &mmio); return 0; } diff --git a/arch/arm/kvm/vgic.c b/arch/arm/kvm/vgic.c new file mode 100644 index 000000000000..c400661409ab --- /dev/null +++ b/arch/arm/kvm/vgic.c @@ -0,0 +1,153 @@ +/* + * Copyright (C) 2012 ARM Ltd. + * Author: Marc Zyngier + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include +#include +#include +#include +#include + +#define ACCESS_READ_VALUE (1 << 0) +#define ACCESS_READ_RAZ (0 << 0) +#define ACCESS_READ_MASK(x) ((x) & (1 << 0)) +#define ACCESS_WRITE_IGNORED (0 << 1) +#define ACCESS_WRITE_SETBIT (1 << 1) +#define ACCESS_WRITE_CLEARBIT (2 << 1) +#define ACCESS_WRITE_VALUE (3 << 1) +#define ACCESS_WRITE_MASK(x) ((x) & (3 << 1)) + +static u32 mmio_data_read(struct kvm_exit_mmio *mmio, u32 mask) +{ + return *((u32 *)mmio->data) & mask; +} + +static void mmio_data_write(struct kvm_exit_mmio *mmio, u32 mask, u32 value) +{ + *((u32 *)mmio->data) = value & mask; +} + +/** + * vgic_reg_access - access vgic register + * @mmio: pointer to the data describing the mmio access + * @reg: pointer to the virtual backing of vgic distributor data + * @offset: least significant 2 bits used for word offset + * @mode: ACCESS_ mode (see defines above) + * + * Helper to make vgic register access easier using one of the access + * modes defined for vgic register access + * (read,raz,write-ignored,setbit,clearbit,write) + */ +static void vgic_reg_access(struct kvm_exit_mmio *mmio, u32 *reg, + phys_addr_t offset, int mode) +{ + int word_offset = (offset & 3) * 8; + u32 mask = (1UL << (mmio->len * 8)) - 1; + u32 regval; + + /* + * Any alignment fault should have been delivered to the guest + * directly (ARM ARM B3.12.7 "Prioritization of aborts"). + */ + + if (reg) { + regval = *reg; + } else { + BUG_ON(mode != (ACCESS_READ_RAZ | ACCESS_WRITE_IGNORED)); + regval = 0; + } + + if (mmio->is_write) { + u32 data = mmio_data_read(mmio, mask) << word_offset; + switch (ACCESS_WRITE_MASK(mode)) { + case ACCESS_WRITE_IGNORED: + return; + + case ACCESS_WRITE_SETBIT: + regval |= data; + break; + + case ACCESS_WRITE_CLEARBIT: + regval &= ~data; + break; + + case ACCESS_WRITE_VALUE: + regval = (regval & ~(mask << word_offset)) | data; + break; + } + *reg = regval; + } else { + switch (ACCESS_READ_MASK(mode)) { + case ACCESS_READ_RAZ: + regval = 0; + /* fall through */ + + case ACCESS_READ_VALUE: + mmio_data_write(mmio, mask, regval >> word_offset); + } + } +} + +/* + * I would have liked to use the kvm_bus_io_*() API instead, but it + * cannot cope with banked registers (only the VM pointer is passed + * around, and we need the vcpu). One of these days, someone please + * fix it! + */ +struct mmio_range { + phys_addr_t base; + unsigned long len; + bool (*handle_mmio)(struct kvm_vcpu *vcpu, struct kvm_exit_mmio *mmio, + phys_addr_t offset); +}; + +static const struct mmio_range vgic_ranges[] = { + {} +}; + +static const +struct mmio_range *find_matching_range(const struct mmio_range *ranges, + struct kvm_exit_mmio *mmio, + phys_addr_t base) +{ + const struct mmio_range *r = ranges; + phys_addr_t addr = mmio->phys_addr - base; + + while (r->len) { + if (addr >= r->base && + (addr + mmio->len) <= (r->base + r->len)) + return r; + r++; + } + + return NULL; +} + +/** + * vgic_handle_mmio - handle an in-kernel MMIO access + * @vcpu: pointer to the vcpu performing the access + * @run: pointer to the kvm_run structure + * @mmio: pointer to the data describing the access + * + * returns true if the MMIO access has been performed in kernel space, + * and false if it needs to be emulated in user space. + */ +bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run, + struct kvm_exit_mmio *mmio) +{ + return KVM_EXIT_MMIO; +} -- 2.20.1