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-rw-r--r--kernel/arch/mips/kvm/interrupt.c242
1 files changed, 242 insertions, 0 deletions
diff --git a/kernel/arch/mips/kvm/interrupt.c b/kernel/arch/mips/kvm/interrupt.c
new file mode 100644
index 000000000..9b4445940
--- /dev/null
+++ b/kernel/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);
+}