diff options
Diffstat (limited to 'arch/mips/kvm/interrupt.c')
| -rw-r--r-- | arch/mips/kvm/interrupt.c | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/arch/mips/kvm/interrupt.c b/arch/mips/kvm/interrupt.c new file mode 100644 index 000000000000..9b4445940c2b --- /dev/null +++ b/arch/mips/kvm/interrupt.c @@ -0,0 +1,242 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * KVM/MIPS: Interrupt delivery + * + * Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved. + * Authors: Sanjay Lal <sanjayl@kymasys.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/vmalloc.h> +#include <linux/fs.h> +#include <linux/bootmem.h> +#include <asm/page.h> +#include <asm/cacheflush.h> + +#include <linux/kvm_host.h> + +#include "interrupt.h" + +void kvm_mips_queue_irq(struct kvm_vcpu *vcpu, uint32_t priority) +{ + set_bit(priority, &vcpu->arch.pending_exceptions); +} + +void kvm_mips_dequeue_irq(struct kvm_vcpu *vcpu, uint32_t priority) +{ + clear_bit(priority, &vcpu->arch.pending_exceptions); +} + +void kvm_mips_queue_timer_int_cb(struct kvm_vcpu *vcpu) +{ + /* + * Cause bits to reflect the pending timer interrupt, + * the EXC code will be set when we are actually + * delivering the interrupt: + */ + kvm_set_c0_guest_cause(vcpu->arch.cop0, (C_IRQ5 | C_TI)); + + /* Queue up an INT exception for the core */ + kvm_mips_queue_irq(vcpu, MIPS_EXC_INT_TIMER); + +} + +void kvm_mips_dequeue_timer_int_cb(struct kvm_vcpu *vcpu) +{ + kvm_clear_c0_guest_cause(vcpu->arch.cop0, (C_IRQ5 | C_TI)); + kvm_mips_dequeue_irq(vcpu, MIPS_EXC_INT_TIMER); +} + +void kvm_mips_queue_io_int_cb(struct kvm_vcpu *vcpu, + struct kvm_mips_interrupt *irq) +{ + int intr = (int)irq->irq; + + /* + * Cause bits to reflect the pending IO interrupt, + * the EXC code will be set when we are actually + * delivering the interrupt: + */ + switch (intr) { + case 2: + kvm_set_c0_guest_cause(vcpu->arch.cop0, (C_IRQ0)); + /* Queue up an INT exception for the core */ + kvm_mips_queue_irq(vcpu, MIPS_EXC_INT_IO); + break; + + case 3: + kvm_set_c0_guest_cause(vcpu->arch.cop0, (C_IRQ1)); + kvm_mips_queue_irq(vcpu, MIPS_EXC_INT_IPI_1); + break; + + case 4: + kvm_set_c0_guest_cause(vcpu->arch.cop0, (C_IRQ2)); + kvm_mips_queue_irq(vcpu, MIPS_EXC_INT_IPI_2); + break; + + default: + break; + } + +} + +void kvm_mips_dequeue_io_int_cb(struct kvm_vcpu *vcpu, + struct kvm_mips_interrupt *irq) +{ + int intr = (int)irq->irq; + + switch (intr) { + case -2: + kvm_clear_c0_guest_cause(vcpu->arch.cop0, (C_IRQ0)); + kvm_mips_dequeue_irq(vcpu, MIPS_EXC_INT_IO); + break; + + case -3: + kvm_clear_c0_guest_cause(vcpu->arch.cop0, (C_IRQ1)); + kvm_mips_dequeue_irq(vcpu, MIPS_EXC_INT_IPI_1); + break; + + case -4: + kvm_clear_c0_guest_cause(vcpu->arch.cop0, (C_IRQ2)); + kvm_mips_dequeue_irq(vcpu, MIPS_EXC_INT_IPI_2); + break; + + default: + break; + } + +} + +/* Deliver the interrupt of the corresponding priority, if possible. */ +int kvm_mips_irq_deliver_cb(struct kvm_vcpu *vcpu, unsigned int priority, + uint32_t cause) +{ + int allowed = 0; + uint32_t exccode; + + struct kvm_vcpu_arch *arch = &vcpu->arch; + struct mips_coproc *cop0 = vcpu->arch.cop0; + + switch (priority) { + case MIPS_EXC_INT_TIMER: + if ((kvm_read_c0_guest_status(cop0) & ST0_IE) + && (!(kvm_read_c0_guest_status(cop0) & (ST0_EXL | ST0_ERL))) + && (kvm_read_c0_guest_status(cop0) & IE_IRQ5)) { + allowed = 1; + exccode = T_INT; + } + break; + + case MIPS_EXC_INT_IO: + if ((kvm_read_c0_guest_status(cop0) & ST0_IE) + && (!(kvm_read_c0_guest_status(cop0) & (ST0_EXL | ST0_ERL))) + && (kvm_read_c0_guest_status(cop0) & IE_IRQ0)) { + allowed = 1; + exccode = T_INT; + } + break; + + case MIPS_EXC_INT_IPI_1: + if ((kvm_read_c0_guest_status(cop0) & ST0_IE) + && (!(kvm_read_c0_guest_status(cop0) & (ST0_EXL | ST0_ERL))) + && (kvm_read_c0_guest_status(cop0) & IE_IRQ1)) { + allowed = 1; + exccode = T_INT; + } + break; + + case MIPS_EXC_INT_IPI_2: + if ((kvm_read_c0_guest_status(cop0) & ST0_IE) + && (!(kvm_read_c0_guest_status(cop0) & (ST0_EXL | ST0_ERL))) + && (kvm_read_c0_guest_status(cop0) & IE_IRQ2)) { + allowed = 1; + exccode = T_INT; + } + break; + + default: + break; + } + + /* Are we allowed to deliver the interrupt ??? */ + if (allowed) { + if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) { + /* save old pc */ + kvm_write_c0_guest_epc(cop0, arch->pc); + kvm_set_c0_guest_status(cop0, ST0_EXL); + + if (cause & CAUSEF_BD) + kvm_set_c0_guest_cause(cop0, CAUSEF_BD); + else + kvm_clear_c0_guest_cause(cop0, CAUSEF_BD); + + kvm_debug("Delivering INT @ pc %#lx\n", arch->pc); + + } else + kvm_err("Trying to deliver interrupt when EXL is already set\n"); + + kvm_change_c0_guest_cause(cop0, CAUSEF_EXCCODE, + (exccode << CAUSEB_EXCCODE)); + + /* XXXSL Set PC to the interrupt exception entry point */ + if (kvm_read_c0_guest_cause(cop0) & CAUSEF_IV) + arch->pc = KVM_GUEST_KSEG0 + 0x200; + else + arch->pc = KVM_GUEST_KSEG0 + 0x180; + + clear_bit(priority, &vcpu->arch.pending_exceptions); + } + + return allowed; +} + +int kvm_mips_irq_clear_cb(struct kvm_vcpu *vcpu, unsigned int priority, + uint32_t cause) +{ + return 1; +} + +void kvm_mips_deliver_interrupts(struct kvm_vcpu *vcpu, uint32_t cause) +{ + unsigned long *pending = &vcpu->arch.pending_exceptions; + unsigned long *pending_clr = &vcpu->arch.pending_exceptions_clr; + unsigned int priority; + + if (!(*pending) && !(*pending_clr)) + return; + + priority = __ffs(*pending_clr); + while (priority <= MIPS_EXC_MAX) { + if (kvm_mips_callbacks->irq_clear(vcpu, priority, cause)) { + if (!KVM_MIPS_IRQ_CLEAR_ALL_AT_ONCE) + break; + } + + priority = find_next_bit(pending_clr, + BITS_PER_BYTE * sizeof(*pending_clr), + priority + 1); + } + + priority = __ffs(*pending); + while (priority <= MIPS_EXC_MAX) { + if (kvm_mips_callbacks->irq_deliver(vcpu, priority, cause)) { + if (!KVM_MIPS_IRQ_DELIVER_ALL_AT_ONCE) + break; + } + + priority = find_next_bit(pending, + BITS_PER_BYTE * sizeof(*pending), + priority + 1); + } + +} + +int kvm_mips_pending_timer(struct kvm_vcpu *vcpu) +{ + return test_bit(MIPS_EXC_INT_TIMER, &vcpu->arch.pending_exceptions); +} |