linux/arch/mips/kvm/interrupt.c
Huacai Chen 3f51d8fcac KVM: MIPS: Add more types of virtual interrupts
In current implementation, MIPS KVM uses IP2, IP3, IP4 and IP7 for
external interrupt, two kinds of IPIs and timer interrupt respectively,
but Loongson-3 based machines prefer to use IP2, IP3, IP6 and IP7 for
two kinds of external interrupts, IPI and timer interrupt. So we define
two priority-irq mapping tables: kvm_loongson3_priority_to_irq[] for
Loongson-3, and kvm_default_priority_to_irq[] for others. The virtual
interrupt infrastructure is updated to deliver all types of interrupts
from IP2, IP3, IP4, IP6 and IP7.

Reviewed-by: Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Co-developed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Message-Id: <1590220602-3547-10-git-send-email-chenhc@lemote.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-04 13:49:13 -04:00

176 lines
4.4 KiB
C

/*
* 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/vmalloc.h>
#include <linux/fs.h>
#include <linux/memblock.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, unsigned int priority)
{
set_bit(priority, &vcpu->arch.pending_exceptions);
}
void kvm_mips_dequeue_irq(struct kvm_vcpu *vcpu, unsigned int 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:
*/
kvm_set_c0_guest_cause(vcpu->arch.cop0, 1 << (intr + 8));
kvm_mips_queue_irq(vcpu, kvm_irq_to_priority(intr));
}
void kvm_mips_dequeue_io_int_cb(struct kvm_vcpu *vcpu,
struct kvm_mips_interrupt *irq)
{
int intr = (int)irq->irq;
kvm_clear_c0_guest_cause(vcpu->arch.cop0, 1 << (-intr + 8));
kvm_mips_dequeue_irq(vcpu, kvm_irq_to_priority(-intr));
}
/* Deliver the interrupt of the corresponding priority, if possible. */
int kvm_mips_irq_deliver_cb(struct kvm_vcpu *vcpu, unsigned int priority,
u32 cause)
{
int allowed = 0;
u32 exccode, ie;
struct kvm_vcpu_arch *arch = &vcpu->arch;
struct mips_coproc *cop0 = vcpu->arch.cop0;
if (priority == MIPS_EXC_MAX)
return 0;
ie = 1 << (kvm_priority_to_irq[priority] + 8);
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)) {
allowed = 1;
exccode = EXCCODE_INT;
}
/* 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 */
arch->pc = kvm_mips_guest_exception_base(vcpu);
if (kvm_read_c0_guest_cause(cop0) & CAUSEF_IV)
arch->pc += 0x200;
else
arch->pc += 0x180;
clear_bit(priority, &vcpu->arch.pending_exceptions);
}
return allowed;
}
int kvm_mips_irq_clear_cb(struct kvm_vcpu *vcpu, unsigned int priority,
u32 cause)
{
return 1;
}
void kvm_mips_deliver_interrupts(struct kvm_vcpu *vcpu, u32 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);
}