Commit 25a2150b authored by Paul Mackerras's avatar Paul Mackerras Committed by Paolo Bonzini
Browse files

KVM: PPC: Enable IRQFD support for the XICS interrupt controller 



This makes it possible to use IRQFDs on platforms that use the XICS
interrupt controller.  To do this we implement kvm_irq_map_gsi() and
kvm_irq_map_chip_pin() in book3s_xics.c, so as to provide a 1-1 mapping
between global interrupt numbers and XICS interrupt source numbers.
For now, all interrupts are mapped as "IRQCHIP" interrupts, and no
MSI support is provided.

This means that kvm_set_irq can now get called with level == 0 or 1
as well as the powerpc-specific values KVM_INTERRUPT_SET,
KVM_INTERRUPT_UNSET and KVM_INTERRUPT_SET_LEVEL.  We change
ics_deliver_irq() to accept all those values, and remove its
report_status argument, as it is always false, given that we don't
support KVM_IRQ_LINE_STATUS.

This also adds support for interrupt ack notifiers to the XICS code
so that the IRQFD resampler functionality can be supported.

Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
Tested-by: default avatarEric Auger <eric.auger@linaro.org>
Tested-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 297e2105

arch/powerpc/kvm/Kconfig

+2 −0
Original line number Diff line number Diff line
@@ -170,6 +170,8 @@ config KVM_MPIC 
config KVM_XICS

	bool "KVM in-kernel XICS emulation"

	depends on KVM_BOOK3S_64 && !KVM_MPIC

	select HAVE_KVM_IRQCHIP

	select HAVE_KVM_IRQFD

	---help---

	  Include support for the XICS (eXternal Interrupt Controller

	  Specification) interrupt controller architecture used on

arch/powerpc/kvm/book3s_hv_rm_xics.c

+5 −0
Original line number Diff line number Diff line
@@ -401,6 +401,11 @@ int kvmppc_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr) 
		icp->rm_action |= XICS_RM_REJECT;

		icp->rm_reject = irq;

	}



	if (!hlist_empty(&vcpu->kvm->irq_ack_notifier_list)) {

		icp->rm_action |= XICS_RM_NOTIFY_EOI;

		icp->rm_eoied_irq = irq;

	}

 bail:

	return check_too_hard(xics, icp);

}

arch/powerpc/kvm/book3s_xics.c

+46 −9
Original line number Diff line number Diff line
@@ -64,8 +64,12 @@ 
static void icp_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp,

			    u32 new_irq);



static int ics_deliver_irq(struct kvmppc_xics *xics, u32 irq, u32 level,

			   bool report_status)

/*

 * Return value ideally indicates how the interrupt was handled, but no

 * callers look at it (given that we don't implement KVM_IRQ_LINE_STATUS),

 * so just return 0.

 */

static int ics_deliver_irq(struct kvmppc_xics *xics, u32 irq, u32 level)

{

	struct ics_irq_state *state;

	struct kvmppc_ics *ics;
@@ -82,17 +86,14 @@ static int ics_deliver_irq(struct kvmppc_xics *xics, u32 irq, u32 level, 
	if (!state->exists)

		return -EINVAL;



	if (report_status)

		return state->asserted;



	/*

	 * We set state->asserted locklessly. This should be fine as

	 * we are the only setter, thus concurrent access is undefined

	 * to begin with.

	 */

	if (level == KVM_INTERRUPT_SET_LEVEL)

	if (level == 1 || level == KVM_INTERRUPT_SET_LEVEL)

		state->asserted = 1;

	else if (level == KVM_INTERRUPT_UNSET) {

	else if (level == 0 || level == KVM_INTERRUPT_UNSET) {

		state->asserted = 0;

		return 0;

	}
@@ -100,7 +101,7 @@ static int ics_deliver_irq(struct kvmppc_xics *xics, u32 irq, u32 level, 
	/* Attempt delivery */

	icp_deliver_irq(xics, NULL, irq);



	return state->asserted;

	return 0;

}



static void ics_check_resend(struct kvmppc_xics *xics, struct kvmppc_ics *ics,
@@ -772,6 +773,8 @@ static noinline int kvmppc_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr) 
	if (state->asserted)

		icp_deliver_irq(xics, icp, irq);



	kvm_notify_acked_irq(vcpu->kvm, 0, irq);



	return H_SUCCESS;

}
@@ -789,6 +792,8 @@ static noinline int kvmppc_xics_rm_complete(struct kvm_vcpu *vcpu, u32 hcall) 
		icp_check_resend(xics, icp);

	if (icp->rm_action & XICS_RM_REJECT)

		icp_deliver_irq(xics, icp, icp->rm_reject);

	if (icp->rm_action & XICS_RM_NOTIFY_EOI)

		kvm_notify_acked_irq(vcpu->kvm, 0, icp->rm_eoied_irq);



	icp->rm_action = 0;
@@ -1170,7 +1175,16 @@ int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level, 
{

	struct kvmppc_xics *xics = kvm->arch.xics;



	return ics_deliver_irq(xics, irq, level, line_status);

	return ics_deliver_irq(xics, irq, level);

}



int kvm_set_msi(struct kvm_kernel_irq_routing_entry *irq_entry, struct kvm *kvm,

		int irq_source_id, int level, bool line_status)

{

	if (!level)

		return -1;

	return kvm_set_irq(kvm, irq_source_id, irq_entry->gsi,

			   level, line_status);

}



static int xics_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
@@ -1301,3 +1315,26 @@ void kvmppc_xics_free_icp(struct kvm_vcpu *vcpu) 
	vcpu->arch.icp = NULL;

	vcpu->arch.irq_type = KVMPPC_IRQ_DEFAULT;

}



static int xics_set_irq(struct kvm_kernel_irq_routing_entry *e,

			struct kvm *kvm, int irq_source_id, int level,

			bool line_status)

{

	return kvm_set_irq(kvm, irq_source_id, e->gsi, level, line_status);

}



int kvm_irq_map_gsi(struct kvm *kvm,

		    struct kvm_kernel_irq_routing_entry *entries, int gsi)

{

	entries->gsi = gsi;

	entries->type = KVM_IRQ_ROUTING_IRQCHIP;

	entries->set = xics_set_irq;

	entries->irqchip.irqchip = 0;

	entries->irqchip.pin = gsi;

	return 1;

}



int kvm_irq_map_chip_pin(struct kvm *kvm, unsigned irqchip, unsigned pin)

{

	return pin;

}

arch/powerpc/kvm/book3s_xics.h

+2 −0
Original line number Diff line number Diff line
@@ -71,9 +71,11 @@ struct kvmppc_icp { 
#define XICS_RM_KICK_VCPU	0x1

#define XICS_RM_CHECK_RESEND	0x2

#define XICS_RM_REJECT		0x4

#define XICS_RM_NOTIFY_EOI	0x8

	u32 rm_action;

	struct kvm_vcpu *rm_kick_target;

	u32  rm_reject;

	u32  rm_eoied_irq;



	/* Debug stuff for real mode */

	union kvmppc_icp_state rm_dbgstate;

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