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>

arch/mips/kvm/interrupt.c

@@ -61,27 +61,8 @@ void kvm_mips_queue_io_int_cb(struct kvm_vcpu *vcpu,
 	 * 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;
-	}
-
+	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,
@@ -89,26 +70,8 @@ void kvm_mips_dequeue_io_int_cb(struct kvm_vcpu *vcpu,
 {
 	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;
-	}
-
+	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. */
@@ -116,50 +79,20 @@ int kvm_mips_irq_deliver_cb(struct kvm_vcpu *vcpu, unsigned int priority,
 			    u32 cause)
 {
 	int allowed = 0;
-	u32 exccode;
+	u32 exccode, ie;
 
 	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 = EXCCODE_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 = EXCCODE_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 = EXCCODE_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 = EXCCODE_INT;
-		}
-		break;
+	if (priority == MIPS_EXC_MAX)
+		return 0;
 
-	default:
-		break;
+	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 ??? */

arch/mips/kvm/interrupt.h

@@ -21,11 +21,12 @@
 #define MIPS_EXC_NMI                5
 #define MIPS_EXC_MCHK               6
 #define MIPS_EXC_INT_TIMER          7
-#define MIPS_EXC_INT_IO             8
-#define MIPS_EXC_EXECUTE            9
-#define MIPS_EXC_INT_IPI_1          10
-#define MIPS_EXC_INT_IPI_2          11
-#define MIPS_EXC_MAX                12
+#define MIPS_EXC_INT_IO_1           8
+#define MIPS_EXC_INT_IO_2           9
+#define MIPS_EXC_EXECUTE            10
+#define MIPS_EXC_INT_IPI_1          11
+#define MIPS_EXC_INT_IPI_2          12
+#define MIPS_EXC_MAX                13
 /* XXXSL More to follow */
 
 #define C_TI        (_ULCAST_(1) << 30)
@@ -38,6 +39,9 @@
 #define KVM_MIPS_IRQ_CLEAR_ALL_AT_ONCE   (0)
 #endif
 
+extern u32 *kvm_priority_to_irq;
+u32 kvm_irq_to_priority(u32 irq);
+
 void kvm_mips_queue_irq(struct kvm_vcpu *vcpu, unsigned int priority);
 void kvm_mips_dequeue_irq(struct kvm_vcpu *vcpu, unsigned int priority);
 int kvm_mips_pending_timer(struct kvm_vcpu *vcpu);

arch/mips/kvm/mips.c

@@ -490,7 +490,10 @@ int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
 	int intr = (int)irq->irq;
 	struct kvm_vcpu *dvcpu = NULL;
 
-	if (intr == 3 || intr == -3 || intr == 4 || intr == -4)
+	if (intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_1] ||
+	    intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_2] ||
+	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_1]) ||
+	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_2]))
 		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
 			  (int)intr);
 
@@ -499,10 +502,10 @@ int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
 	else
 		dvcpu = vcpu->kvm->vcpus[irq->cpu];
 
-	if (intr == 2 || intr == 3 || intr == 4) {
+	if (intr == 2 || intr == 3 || intr == 4 || intr == 6) {
 		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
 
-	} else if (intr == -2 || intr == -3 || intr == -4) {
+	} else if (intr == -2 || intr == -3 || intr == -4 || intr == -6) {
 		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
 	} else {
 		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
@@ -1620,6 +1623,34 @@ static struct notifier_block kvm_mips_csr_die_notifier = {
 	.notifier_call = kvm_mips_csr_die_notify,
 };
 
+static u32 kvm_default_priority_to_irq[MIPS_EXC_MAX] = {
+	[MIPS_EXC_INT_TIMER] = C_IRQ5,
+	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
+	[MIPS_EXC_INT_IPI_1] = C_IRQ1,
+	[MIPS_EXC_INT_IPI_2] = C_IRQ2,
+};
+
+static u32 kvm_loongson3_priority_to_irq[MIPS_EXC_MAX] = {
+	[MIPS_EXC_INT_TIMER] = C_IRQ5,
+	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
+	[MIPS_EXC_INT_IO_2]  = C_IRQ1,
+	[MIPS_EXC_INT_IPI_1] = C_IRQ4,
+};
+
+u32 *kvm_priority_to_irq = kvm_default_priority_to_irq;
+
+u32 kvm_irq_to_priority(u32 irq)
+{
+	int i;
+
+	for (i = MIPS_EXC_INT_TIMER; i < MIPS_EXC_MAX; i++) {
+		if (kvm_priority_to_irq[i] == (1 << (irq + 8)))
+			return i;
+	}
+
+	return MIPS_EXC_MAX;
+}
+
 static int __init kvm_mips_init(void)
 {
 	int ret;
@@ -1638,6 +1669,9 @@ static int __init kvm_mips_init(void)
 	if (ret)
 		return ret;
 
+	if (boot_cpu_type() == CPU_LOONGSON64)
+		kvm_priority_to_irq = kvm_loongson3_priority_to_irq;
+
 	register_die_notifier(&kvm_mips_csr_die_notifier);
 
 	return 0;

arch/mips/kvm/vz.c

@@ -225,23 +225,7 @@ static void kvm_vz_queue_io_int_cb(struct kvm_vcpu *vcpu,
 	 * interrupts are asynchronous to vcpu execution therefore defer guest
 	 * cp0 accesses
 	 */
-	switch (intr) {
-	case 2:
-		kvm_vz_queue_irq(vcpu, MIPS_EXC_INT_IO);
-		break;
-
-	case 3:
-		kvm_vz_queue_irq(vcpu, MIPS_EXC_INT_IPI_1);
-		break;
-
-	case 4:
-		kvm_vz_queue_irq(vcpu, MIPS_EXC_INT_IPI_2);
-		break;
-
-	default:
-		break;
-	}
-
+	kvm_vz_queue_irq(vcpu, kvm_irq_to_priority(intr));
 }
 
 static void kvm_vz_dequeue_io_int_cb(struct kvm_vcpu *vcpu,
@@ -253,44 +237,22 @@ static void kvm_vz_dequeue_io_int_cb(struct kvm_vcpu *vcpu,
 	 * interrupts are asynchronous to vcpu execution therefore defer guest
 	 * cp0 accesses
 	 */
-	switch (intr) {
-	case -2:
-		kvm_vz_dequeue_irq(vcpu, MIPS_EXC_INT_IO);
-		break;
-
-	case -3:
-		kvm_vz_dequeue_irq(vcpu, MIPS_EXC_INT_IPI_1);
-		break;
-
-	case -4:
-		kvm_vz_dequeue_irq(vcpu, MIPS_EXC_INT_IPI_2);
-		break;
-
-	default:
-		break;
-	}
-
+	kvm_vz_dequeue_irq(vcpu, kvm_irq_to_priority(-intr));
 }
 
-static u32 kvm_vz_priority_to_irq[MIPS_EXC_MAX] = {
-	[MIPS_EXC_INT_TIMER] = C_IRQ5,
-	[MIPS_EXC_INT_IO]    = C_IRQ0,
-	[MIPS_EXC_INT_IPI_1] = C_IRQ1,
-	[MIPS_EXC_INT_IPI_2] = C_IRQ2,
-};
-
 static int kvm_vz_irq_deliver_cb(struct kvm_vcpu *vcpu, unsigned int priority,
 				 u32 cause)
 {
 	u32 irq = (priority < MIPS_EXC_MAX) ?
-		kvm_vz_priority_to_irq[priority] : 0;
+		kvm_priority_to_irq[priority] : 0;
 
 	switch (priority) {
 	case MIPS_EXC_INT_TIMER:
 		set_gc0_cause(C_TI);
 		break;
 
-	case MIPS_EXC_INT_IO:
+	case MIPS_EXC_INT_IO_1:
+	case MIPS_EXC_INT_IO_2:
 	case MIPS_EXC_INT_IPI_1:
 	case MIPS_EXC_INT_IPI_2:
 		if (cpu_has_guestctl2)
@@ -311,7 +273,7 @@ static int kvm_vz_irq_clear_cb(struct kvm_vcpu *vcpu, unsigned int priority,
 			       u32 cause)
 {
 	u32 irq = (priority < MIPS_EXC_MAX) ?
-		kvm_vz_priority_to_irq[priority] : 0;
+		kvm_priority_to_irq[priority] : 0;
 
 	switch (priority) {
 	case MIPS_EXC_INT_TIMER:
@@ -329,7 +291,8 @@ static int kvm_vz_irq_clear_cb(struct kvm_vcpu *vcpu, unsigned int priority,
 		}
 		break;
 
-	case MIPS_EXC_INT_IO:
+	case MIPS_EXC_INT_IO_1:
+	case MIPS_EXC_INT_IO_2:
 	case MIPS_EXC_INT_IPI_1:
 	case MIPS_EXC_INT_IPI_2:
 		/* Clear GuestCtl2.VIP irq if not using Hardware Clear */