@@ -142,6 +142,7 @@ extern int kvmppc_mmu_hv_init(void);
extern int kvmppc_ld(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr, bool data);
extern int kvmppc_st(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr, bool data);
extern void kvmppc_book3s_queue_irqprio(struct kvm_vcpu *vcpu, unsigned int vec);
+extern void kvmppc_book3s_dequeue_irqprio(struct kvm_vcpu *vcpu, unsigned int vec);
extern void kvmppc_inject_interrupt(struct kvm_vcpu *vcpu, int vec, u64 flags);
extern void kvmppc_set_bat(struct kvm_vcpu *vcpu, struct kvmppc_bat *bat,
bool upper, u32 val);
@@ -188,6 +188,10 @@ struct kvmppc_linear_info {
int type;
};
+/* XICS components, defined in boo3s_xics.c */
+struct kvmppc_xics;
+struct kvmppc_icp;
+
/*
* The reverse mapping array has one entry for each HPTE,
* which stores the guest's view of the second word of the HPTE
@@ -256,6 +260,7 @@ struct kvm_arch {
#ifdef CONFIG_PPC_BOOK3S_64
struct list_head spapr_tce_tables;
struct list_head rtas_tokens;
+ struct kvmppc_xics *xics;
#endif
};
@@ -378,6 +383,7 @@ struct kvmppc_booke_debug_reg {
#define KVMPPC_IRQ_DEFAULT 0
#define KVMPPC_IRQ_MPIC 1
+#define KVMPPC_IRQ_XICS 2
struct openpic;
@@ -562,6 +568,9 @@ struct kvm_vcpu_arch {
int irq_type; /* one of KVM_IRQ_* */
struct openpic *mpic; /* KVM_IRQ_MPIC */
+#ifdef CONFIG_KVM_XICS
+ struct kvmppc_icp *icp; /* XICS presentation controller */
+#endif
#ifdef CONFIG_KVM_BOOK3S_64_HV
struct kvm_vcpu_arch_shared shregs;
@@ -130,6 +130,8 @@ extern long kvmppc_prepare_vrma(struct kvm *kvm,
extern void kvmppc_map_vrma(struct kvm_vcpu *vcpu,
struct kvm_memory_slot *memslot, unsigned long porder);
extern int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu);
+extern int kvmppc_xics_hcall(struct kvm_vcpu *vcpu, u32 cmd);
+
extern long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
struct kvm_create_spapr_tce *args);
extern long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
@@ -169,6 +171,8 @@ int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu, struct kvm_interrupt *irq);
extern int kvm_vm_ioctl_rtas_define_token(struct kvm *kvm, void __user *argp);
extern int kvmppc_rtas_hcall(struct kvm_vcpu *vcpu);
extern void kvmppc_rtas_tokens_free(struct kvm *kvm);
+extern int kvmppc_xics_set_xive(struct kvm *kvm, u32 irq, u32 server, u32 priority);
+extern int kvmppc_xics_get_xive(struct kvm *kvm, u32 irq, u32 *server, u32 *priority);
/*
* Cuts out inst bits with ordering according to spec.
@@ -268,6 +272,27 @@ static inline void kvmppc_set_xics_phys(int cpu, unsigned long addr)
static inline void kvm_linear_init(void)
{}
+
+#endif
+
+#ifdef CONFIG_PPC_BOOK3S_64
+static inline int kvmppc_xics_enabled(struct kvm_vcpu *vcpu)
+{
+ return vcpu->arch.irq_type == KVMPPC_IRQ_XICS;
+}
+extern void kvmppc_xics_free_icp(struct kvm_vcpu *vcpu);
+extern int kvmppc_xics_create_icp(struct kvm_vcpu *vcpu, unsigned long server);
+extern int kvm_vm_ioctl_xics_irq(struct kvm *kvm, struct kvm_irq_level *args);
+#else
+static inline int kvmppc_xics_enabled(struct kvm_vcpu *vcpu)
+ { return 0; }
+static inline void kvmppc_xics_free_icp(struct kvm_vcpu *vcpu) { }
+static inline int kvmppc_xics_create_icp(struct kvm_vcpu *vcpu,
+ unsigned long server)
+ { return -EINVAL; }
+static inline int kvm_vm_ioctl_xics_irq(struct kvm *kvm,
+ struct kvm_irq_level *args)
+ { return -ENOTTY; }
#endif
static inline void kvmppc_set_epr(struct kvm_vcpu *vcpu, u32 epr)
@@ -282,6 +307,8 @@ static inline void kvmppc_set_epr(struct kvm_vcpu *vcpu, u32 epr)
void kvmppc_mpic_set_epr(struct kvm_vcpu *vcpu);
int kvmppc_mpic_connect_vcpu(struct file *mpic_filp, struct kvm_vcpu *vcpu,
u32 cpu);
+int kvmppc_xics_connect_vcpu(struct file *xics_filp, struct kvm_vcpu *vcpu,
+ u32 cpu);
int kvm_vcpu_ioctl_config_tlb(struct kvm_vcpu *vcpu,
struct kvm_config_tlb *cfg);
@@ -428,4 +428,5 @@ struct kvm_get_htab_header {
#define KVM_REG_PPC_CLEAR_TSR (KVM_REG_PPC | KVM_REG_SIZE_U32 | 0x88)
#define KVM_REG_PPC_TCR (KVM_REG_PPC | KVM_REG_SIZE_U32 | 0x89)
#define KVM_REG_PPC_TSR (KVM_REG_PPC | KVM_REG_SIZE_U32 | 0x8a)
+
#endif /* __LINUX_KVM_POWERPC_H */
@@ -155,6 +155,14 @@ config KVM_MPIC
bool "KVM in-kernel MPIC emulation"
depends on KVM
+config KVM_XICS
+ bool "KVM in-kernel XICS emulation"
+ depends on KVM_BOOK3S_64
+ ---help---
+ Include support for the XICS (eXternal Interrupt Controller
+ Specification) interrupt controller architecture used on
+ IBM POWER (pSeries) servers.
+
source drivers/vhost/Kconfig
@@ -79,6 +79,9 @@ kvm-book3s_64-builtin-objs-$(CONFIG_KVM_BOOK3S_64_HV) := \
book3s_hv_ras.o \
book3s_hv_builtin.o
+kvm-book3s_64-objs-$(CONFIG_KVM_XICS) += \
+ book3s_xics.o
+
kvm-book3s_64-module-objs := \
../../../virt/kvm/kvm_main.o \
../../../virt/kvm/eventfd.o \
@@ -104,7 +104,7 @@ static int kvmppc_book3s_vec2irqprio(unsigned int vec)
return prio;
}
-static void kvmppc_book3s_dequeue_irqprio(struct kvm_vcpu *vcpu,
+void kvmppc_book3s_dequeue_irqprio(struct kvm_vcpu *vcpu,
unsigned int vec)
{
unsigned long old_pending = vcpu->arch.pending_exceptions;
@@ -528,6 +528,15 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
/* Send the error out to userspace via KVM_RUN */
return rc;
+
+ case H_XIRR:
+ case H_CPPR:
+ case H_EOI:
+ case H_IPI:
+ if (kvmppc_xics_enabled(vcpu)) {
+ ret = kvmppc_xics_hcall(vcpu, req);
+ break;
+ } /* fallthrough */
default:
return RESUME_HOST;
}
@@ -227,6 +227,15 @@ static int kvmppc_h_pr_put_tce(struct kvm_vcpu *vcpu)
return EMULATE_DONE;
}
+static int kvmppc_h_pr_xics_hcall(struct kvm_vcpu *vcpu, u32 cmd)
+{
+ long rc = kvmppc_xics_hcall(vcpu, cmd);
+ if (rc == H_TOO_HARD)
+ return EMULATE_FAIL;
+ kvmppc_set_gpr(vcpu, 3, rc);
+ return EMULATE_DONE;
+}
+
int kvmppc_h_pr(struct kvm_vcpu *vcpu, unsigned long cmd)
{
switch (cmd) {
@@ -246,6 +255,13 @@ int kvmppc_h_pr(struct kvm_vcpu *vcpu, unsigned long cmd)
clear_bit(KVM_REQ_UNHALT, &vcpu->requests);
vcpu->stat.halt_wakeup++;
return EMULATE_DONE;
+ case H_XIRR:
+ case H_CPPR:
+ case H_EOI:
+ case H_IPI:
+ if (kvmppc_xics_enabled(vcpu))
+ return kvmppc_h_pr_xics_hcall(vcpu, cmd);
+ break;
case H_RTAS:
if (list_empty(&vcpu->kvm->arch.rtas_tokens))
return RESUME_HOST;
@@ -18,12 +18,61 @@
#include <asm/rtas.h>
+static void kvm_rtas_set_xive(struct kvm_vcpu *vcpu, struct rtas_args *args)
+{
+ u32 irq, server, priority;
+ int rc;
+
+ if (args->nargs != 3 || args->nret != 1) {
+ rc = -3;
+ goto out;
+ }
+
+ irq = args->args[0];
+ server = args->args[1];
+ priority = args->args[2];
+
+ rc = kvmppc_xics_set_xive(vcpu->kvm, irq, server, priority);
+ if (rc)
+ rc = -3;
+out:
+ args->rets[0] = rc;
+}
+
+static void kvm_rtas_get_xive(struct kvm_vcpu *vcpu, struct rtas_args *args)
+{
+ u32 irq, server, priority;
+ int rc;
+
+ if (args->nargs != 1 || args->nret != 3) {
+ rc = -3;
+ goto out;
+ }
+
+ irq = args->args[0];
+
+ server = priority = 0;
+ rc = kvmppc_xics_get_xive(vcpu->kvm, irq, &server, &priority);
+ if (rc) {
+ rc = -3;
+ goto out;
+ }
+
+ args->rets[1] = server;
+ args->rets[2] = priority;
+out:
+ args->rets[0] = rc;
+}
+
struct rtas_handler {
void (*handler)(struct kvm_vcpu *vcpu, struct rtas_args *args);
char *name;
};
-static struct rtas_handler rtas_handlers[] = { };
+static struct rtas_handler rtas_handlers[] = {
+ { .name = "ibm,set-xive", .handler = kvm_rtas_set_xive },
+ { .name = "ibm,get-xive", .handler = kvm_rtas_get_xive },
+};
struct rtas_token_definition {
struct list_head list;
new file mode 100644
@@ -0,0 +1,942 @@
+/*
+ * Copyright 2012 Michael Ellerman, IBM Corporation.
+ * Copyright 2012 Benjamin Herrenschmidt, IBM Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/kvm_host.h>
+#include <linux/err.h>
+#include <linux/gfp.h>
+
+#include <asm/uaccess.h>
+#include <asm/kvm_book3s.h>
+#include <asm/kvm_ppc.h>
+#include <asm/hvcall.h>
+#include <asm/xics.h>
+#include <asm/debug.h>
+
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+#include "book3s_xics.h"
+
+#define XICS_DBG(fmt...) do { } while (0)
+//#define XICS_DBG(fmt...) do { trace_printk(fmt); } while (0)
+
+/*
+ * LOCKING
+ * =======
+ *
+ * Each ICS has a mutex protecting the information about the IRQ
+ * sources and avoiding simultaneous deliveries if the same interrupt.
+ *
+ * ICP operations are done via a single compare & swap transaction
+ * (most ICP state fits in the union kvmppc_icp_state)
+ */
+
+/*
+ * TODO
+ * ====
+ *
+ * - To speed up resends, keep a bitmap of "resend" set bits in the
+ * ICS
+ *
+ * - Speed up server# -> ICP lookup (array ? hash table ?)
+ *
+ * - Make ICS lockless as well, or at least a per-interrupt lock or hashed
+ * locks array to improve scalability
+ *
+ * - ioctl's to save/restore the entire state for snapshot & migration
+ */
+
+/* -- ICS routines -- */
+
+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)
+{
+ struct ics_irq_state *state;
+ struct kvmppc_ics *ics;
+ u16 src;
+
+ XICS_DBG("ics deliver %#x (level: %d)\n", irq, level);
+
+ ics = kvmppc_xics_find_ics(xics, irq, &src);
+ if (!ics) {
+ XICS_DBG("ics_deliver_irq: IRQ 0x%06x not found !\n", irq);
+ return -EINVAL;
+ }
+ state = &ics->irq_state[src];
+ if (!state->exists)
+ return -EINVAL;
+
+ /*
+ * 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)
+ state->asserted = 1;
+ else if (level == KVM_INTERRUPT_UNSET) {
+ state->asserted = 0;
+ return 0;
+ }
+
+ /* Attempt delivery */
+ icp_deliver_irq(xics, NULL, irq);
+
+ return 0;
+}
+
+static void ics_check_resend(struct kvmppc_xics *xics, struct kvmppc_ics *ics,
+ struct kvmppc_icp *icp)
+{
+ int i;
+
+ mutex_lock(&ics->lock);
+
+ for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) {
+ struct ics_irq_state *state = &ics->irq_state[i];
+
+ if (!state->resend)
+ continue;
+
+ XICS_DBG("resend %#x prio %#x\n", state->number,
+ state->priority);
+
+ mutex_unlock(&ics->lock);
+ icp_deliver_irq(xics, icp, state->number);
+ mutex_lock(&ics->lock);
+ }
+
+ mutex_unlock(&ics->lock);
+}
+
+int kvmppc_xics_set_xive(struct kvm *kvm, u32 irq, u32 server, u32 priority)
+{
+ struct kvmppc_xics *xics = kvm->arch.xics;
+ struct kvmppc_icp *icp;
+ struct kvmppc_ics *ics;
+ struct ics_irq_state *state;
+ u16 src;
+ bool deliver;
+
+ if (!xics)
+ return -ENODEV;
+
+ ics = kvmppc_xics_find_ics(xics, irq, &src);
+ if (!ics)
+ return -EINVAL;
+ state = &ics->irq_state[src];
+
+ icp = kvmppc_xics_find_server(kvm, server);
+ if (!icp)
+ return -EINVAL;
+
+ mutex_lock(&ics->lock);
+
+ XICS_DBG("set_xive %#x server %#x prio %#x MP:%d RS:%d\n",
+ irq, server, priority,
+ state->masked_pending, state->resend);
+
+ state->server = server;
+ state->priority = priority;
+ deliver = false;
+ if ((state->masked_pending || state->resend) && priority != MASKED) {
+ state->masked_pending = 0;
+ deliver = true;
+ }
+
+ mutex_unlock(&ics->lock);
+
+ if (deliver)
+ icp_deliver_irq(xics, icp, irq);
+
+ return 0;
+}
+
+int kvmppc_xics_get_xive(struct kvm *kvm, u32 irq, u32 *server, u32 *priority)
+{
+ struct kvmppc_xics *xics = kvm->arch.xics;
+ struct kvmppc_ics *ics;
+ struct ics_irq_state *state;
+ u16 src;
+
+ if (!xics)
+ return -ENODEV;
+
+ ics = kvmppc_xics_find_ics(xics, irq, &src);
+ if (!ics)
+ return -EINVAL;
+ state = &ics->irq_state[src];
+
+ mutex_lock(&ics->lock);
+ *server = state->server;
+ *priority = state->priority;
+ mutex_unlock(&ics->lock);
+
+ return 0;
+}
+
+/* -- ICP routines, including hcalls -- */
+
+static inline bool icp_try_update(struct kvmppc_icp *icp,
+ union kvmppc_icp_state old,
+ union kvmppc_icp_state new,
+ bool change_self)
+{
+ bool success;
+
+ /* Calculate new output value */
+ new.out_ee = (new.xisr && (new.pending_pri < new.cppr));
+
+ /* Attempt atomic update */
+ success = cmpxchg64(&icp->state.raw, old.raw, new.raw) == old.raw;
+ if (!success)
+ goto bail;
+
+ XICS_DBG("UPD [%04x] - C:%02x M:%02x PP: %02x PI:%06x R:%d O:%d\n",
+ icp->vcpu->vcpu_id,
+ old.cppr, old.mfrr, old.pending_pri, old.xisr,
+ old.need_resend, old.out_ee);
+ XICS_DBG("UPD - C:%02x M:%02x PP: %02x PI:%06x R:%d O:%d\n",
+ new.cppr, new.mfrr, new.pending_pri, new.xisr,
+ new.need_resend, new.out_ee);
+ /*
+ * Check for output state update
+ *
+ * Note that this is racy since another processor could be updating
+ * the state already. This is why we never clear the interrupt output
+ * here, we only ever set it. The clear only happens prior to doing
+ * an update and only by the processor itself. Currently we do it
+ * in Accept (H_XIRR) and Up_Cppr (H_XPPR).
+ *
+ * We also do not try to figure out whether the EE state has changed,
+ * we unconditionally set it if the new state calls for it for the
+ * same reason.
+ */
+ if (new.out_ee) {
+ kvmppc_book3s_queue_irqprio(icp->vcpu,
+ BOOK3S_INTERRUPT_EXTERNAL_LEVEL);
+ if (!change_self)
+ kvm_vcpu_kick(icp->vcpu);
+ }
+ bail:
+ return success;
+}
+
+static void icp_check_resend(struct kvmppc_xics *xics,
+ struct kvmppc_icp *icp)
+{
+ u32 icsid;
+
+ /* Order this load with the test for need_resend in the caller */
+ smp_rmb();
+ for_each_set_bit(icsid, icp->resend_map, xics->max_icsid + 1) {
+ struct kvmppc_ics *ics = xics->ics[icsid];
+
+ if (!test_and_clear_bit(icsid, icp->resend_map))
+ continue;
+ if (!ics)
+ continue;
+ ics_check_resend(xics, ics, icp);
+ }
+}
+
+static bool icp_try_to_deliver(struct kvmppc_icp *icp, u32 irq, u8 priority,
+ u32 *reject)
+{
+ union kvmppc_icp_state old_state, new_state;
+ bool success;
+
+ XICS_DBG("try deliver %#x(P:%#x) to server %#x\n", irq, priority,
+ icp->vcpu->vcpu_id);
+
+ do {
+ old_state = new_state = ACCESS_ONCE(icp->state);
+
+ *reject = 0;
+
+ /* See if we can deliver */
+ success = new_state.cppr > priority &&
+ new_state.mfrr > priority &&
+ new_state.pending_pri > priority;
+
+ /*
+ * If we can, check for a rejection and perform the
+ * delivery
+ */
+ if (success) {
+ *reject = new_state.xisr;
+ new_state.xisr = irq;
+ new_state.pending_pri = priority;
+ } else {
+ /*
+ * If we failed to deliver we set need_resend
+ * so a subsequent CPPR state change causes us
+ * to try a new delivery.
+ */
+ new_state.need_resend = true;
+ }
+
+ } while (!icp_try_update(icp, old_state, new_state, false));
+
+ return success;
+}
+
+static void icp_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp,
+ u32 new_irq)
+{
+ struct ics_irq_state *state;
+ struct kvmppc_ics *ics;
+ u32 reject;
+ u16 src;
+
+ /*
+ * This is used both for initial delivery of an interrupt and
+ * for subsequent rejection.
+ *
+ * Rejection can be racy vs. resends. We have evaluated the
+ * rejection in an atomic ICP transaction which is now complete,
+ * so potentially the ICP can already accept the interrupt again.
+ *
+ * So we need to retry the delivery. Essentially the reject path
+ * boils down to a failed delivery. Always.
+ *
+ * Now the interrupt could also have moved to a different target,
+ * thus we may need to re-do the ICP lookup as well
+ */
+
+ again:
+ /* Get the ICS state and lock it */
+ ics = kvmppc_xics_find_ics(xics, new_irq, &src);
+ if (!ics) {
+ XICS_DBG("icp_deliver_irq: IRQ 0x%06x not found !\n", new_irq);
+ return;
+ }
+ state = &ics->irq_state[src];
+
+ /* Get a lock on the ICS */
+ mutex_lock(&ics->lock);
+
+ /* Get our server */
+ if (!icp || state->server != icp->vcpu->vcpu_id) {
+ icp = kvmppc_xics_find_server(xics->kvm, state->server);
+ if (!icp) {
+ pr_warning("icp_deliver_irq: IRQ 0x%06x server 0x%x"
+ " not found !\n", new_irq, state->server);
+ goto out;
+ }
+ }
+
+ /* Clear the resend bit of that interrupt */
+ state->resend = 0;
+
+ /*
+ * If masked, bail out
+ *
+ * Note: PAPR doesn't mention anything about masked pending
+ * when doing a resend, only when doing a delivery.
+ *
+ * However that would have the effect of losing a masked
+ * interrupt that was rejected and isn't consistent with
+ * the whole masked_pending business which is about not
+ * losing interrupts that occur while masked.
+ *
+ * I don't differenciate normal deliveries and resends, this
+ * implementation will differ from PAPR and not lose such
+ * interrupts.
+ */
+ if (state->priority == MASKED) {
+ XICS_DBG("irq %#x masked pending\n", new_irq);
+ state->masked_pending = 1;
+ goto out;
+ }
+
+ /*
+ * Try the delivery, this will set the need_resend flag
+ * in the ICP as part of the atomic transaction if the
+ * delivery is not possible.
+ *
+ * Note that if successful, the new delivery might have itself
+ * rejected an interrupt that was "delivered" before we took the
+ * icp mutex.
+ *
+ * In this case we do the whole sequence all over again for the
+ * new guy. We cannot assume that the rejected interrupt is less
+ * favored than the new one, and thus doesn't need to be delivered,
+ * because by the time we exit icp_try_to_deliver() the target
+ * processor may well have alrady consumed & completed it, and thus
+ * the rejected interrupt might actually be already acceptable.
+ */
+ if (icp_try_to_deliver(icp, new_irq, state->priority, &reject)) {
+ /*
+ * Delivery was successful, did we reject somebody else ?
+ */
+ if (reject && reject != XICS_IPI) {
+ mutex_unlock(&ics->lock);
+ new_irq = reject;
+ goto again;
+ }
+ } else {
+ /*
+ * We failed to deliver the interrupt we need to set the
+ * resend map bit and mark the ICS state as needing a resend
+ */
+ set_bit(ics->icsid, icp->resend_map);
+ state->resend = 1;
+
+ /*
+ * If the need_resend flag got cleared in the ICP some time
+ * between icp_try_to_deliver() atomic update and now, then
+ * we know it might have missed the resend_map bit. So we
+ * retry
+ */
+ smp_mb();
+ if (!icp->state.need_resend) {
+ mutex_unlock(&ics->lock);
+ goto again;
+ }
+ }
+ out:
+ mutex_unlock(&ics->lock);
+}
+
+static void icp_down_cppr(struct kvmppc_xics *xics, struct kvmppc_icp *icp,
+ u8 new_cppr)
+{
+ union kvmppc_icp_state old_state, new_state;
+ bool resend;
+
+ /*
+ * This handles several related states in one operation:
+ *
+ * ICP State: Down_CPPR
+ *
+ * Load CPPR with new value and if the XISR is 0
+ * then check for resends:
+ *
+ * ICP State: Resend
+ *
+ * If MFRR is more favored than CPPR, check for IPIs
+ * and notify ICS of a potential resend. This is done
+ * asynchronously (when used in real mode, we will have
+ * to exit here).
+ *
+ * We do not handle the complete Check_IPI as documented
+ * here. In the PAPR, this state will be used for both
+ * Set_MFRR and Down_CPPR. However, we know that we aren't
+ * changing the MFRR state here so we don't need to handle
+ * the case of an MFRR causing a reject of a pending irq,
+ * this will have been handled when the MFRR was set in the
+ * first place.
+ *
+ * Thus we don't have to handle rejects, only resends.
+ *
+ * When implementing real mode for HV KVM, resend will lead to
+ * a H_TOO_HARD return and the whole transaction will be handled
+ * in virtual mode.
+ */
+ do {
+ old_state = new_state = ACCESS_ONCE(icp->state);
+
+ /* Down_CPPR */
+ new_state.cppr = new_cppr;
+
+ /*
+ * Cut down Resend / Check_IPI / IPI
+ *
+ * The logic is that we cannot have a pending interrupt
+ * trumped by an IPI at this point (see above), so we
+ * know that either the pending interrupt is already an
+ * IPI (in which case we don't care to override it) or
+ * it's either more favored than us or non existent
+ */
+ if (new_state.mfrr < new_cppr &&
+ new_state.mfrr <= new_state.pending_pri) {
+ WARN_ON(new_state.xisr != XICS_IPI &&
+ new_state.xisr != 0);
+ new_state.pending_pri = new_state.mfrr;
+ new_state.xisr = XICS_IPI;
+ }
+
+ /* Latch/clear resend bit */
+ resend = new_state.need_resend;
+ new_state.need_resend = 0;
+
+ } while (!icp_try_update(icp, old_state, new_state, true));
+
+ /*
+ * Now handle resend checks. Those are asynchronous to the ICP
+ * state update in HW (ie bus transactions) so we can handle them
+ * separately here too
+ */
+ if (resend)
+ icp_check_resend(xics, icp);
+}
+
+static noinline unsigned long h_xirr(struct kvm_vcpu *vcpu)
+{
+ union kvmppc_icp_state old_state, new_state;
+ struct kvmppc_icp *icp = vcpu->arch.icp;
+ u32 xirr;
+
+ /* First, remove EE from the processor */
+ kvmppc_book3s_dequeue_irqprio(icp->vcpu,
+ BOOK3S_INTERRUPT_EXTERNAL_LEVEL);
+
+ /*
+ * ICP State: Accept_Interrupt
+ *
+ * Return the pending interrupt (if any) along with the
+ * current CPPR, then clear the XISR & set CPPR to the
+ * pending priority
+ */
+ do {
+ old_state = new_state = ACCESS_ONCE(icp->state);
+
+ xirr = old_state.xisr | (((u32)old_state.cppr) << 24);
+ if (!old_state.xisr)
+ break;
+ new_state.cppr = new_state.pending_pri;
+ new_state.pending_pri = 0xff;
+ new_state.xisr = 0;
+
+ } while (!icp_try_update(icp, old_state, new_state, true));
+
+ XICS_DBG("h_xirr vcpu %d xirr %#x\n", vcpu->vcpu_id, xirr);
+
+ return xirr;
+}
+
+static noinline int h_ipi(struct kvm_vcpu *vcpu, unsigned long server,
+ unsigned long mfrr)
+{
+ union kvmppc_icp_state old_state, new_state;
+ struct kvmppc_xics *xics = vcpu->kvm->arch.xics;
+ struct kvmppc_icp *icp;
+ u32 reject;
+ bool resend;
+ bool local;
+
+ XICS_DBG("h_ipi vcpu %d to server %lu mfrr %#lx\n",
+ vcpu->vcpu_id, server, mfrr);
+
+ local = vcpu->vcpu_id == server;
+ if (local)
+ icp = vcpu->arch.icp;
+ else
+ icp = kvmppc_xics_find_server(vcpu->kvm, server);
+ if (!icp)
+ return H_PARAMETER;
+
+ /*
+ * ICP state: Set_MFRR
+ *
+ * If the CPPR is more favored than the new MFRR, then
+ * nothing needs to be rejected as there can be no XISR to
+ * reject. If the MFRR is being made less favored then
+ * there might be a previously-rejected interrupt needing
+ * to be resent.
+ *
+ * If the CPPR is less favored, then we might be replacing
+ * an interrupt, and thus need to possibly reject it as in
+ *
+ * ICP state: Check_IPI
+ */
+ do {
+ old_state = new_state = ACCESS_ONCE(icp->state);
+
+ /* Set_MFRR */
+ new_state.mfrr = mfrr;
+
+ /* Check_IPI */
+ reject = 0;
+ resend = false;
+ if (mfrr < new_state.cppr) {
+ /* Reject a pending interrupt if not an IPI */
+ if (mfrr <= new_state.pending_pri)
+ reject = new_state.xisr;
+ new_state.pending_pri = mfrr;
+ new_state.xisr = XICS_IPI;
+ }
+
+ if (mfrr > old_state.mfrr && mfrr > new_state.cppr) {
+ resend = new_state.need_resend;
+ new_state.need_resend = 0;
+ }
+ } while (!icp_try_update(icp, old_state, new_state, local));
+
+ /* Handle reject */
+ if (reject && reject != XICS_IPI)
+ icp_deliver_irq(xics, icp, reject);
+
+ /* Handle resend */
+ if (resend)
+ icp_check_resend(xics, icp);
+
+ return H_SUCCESS;
+}
+
+static noinline void h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr)
+{
+ union kvmppc_icp_state old_state, new_state;
+ struct kvmppc_xics *xics = vcpu->kvm->arch.xics;
+ struct kvmppc_icp *icp = vcpu->arch.icp;
+ u32 reject;
+
+ XICS_DBG("h_cppr vcpu %d cppr %#lx\n", vcpu->vcpu_id, cppr);
+
+ /*
+ * ICP State: Set_CPPR
+ *
+ * We can safely compare the new value with the current
+ * value outside of the transaction as the CPPR is only
+ * ever changed by the processor on itself
+ */
+ if (cppr > icp->state.cppr)
+ icp_down_cppr(xics, icp, cppr);
+ else if (cppr == icp->state.cppr)
+ return;
+
+ /*
+ * ICP State: Up_CPPR
+ *
+ * The processor is raising its priority, this can result
+ * in a rejection of a pending interrupt:
+ *
+ * ICP State: Reject_Current
+ *
+ * We can remove EE from the current processor, the update
+ * transaction will set it again if needed
+ */
+ kvmppc_book3s_dequeue_irqprio(icp->vcpu,
+ BOOK3S_INTERRUPT_EXTERNAL_LEVEL);
+
+ do {
+ old_state = new_state = ACCESS_ONCE(icp->state);
+
+ reject = 0;
+ new_state.cppr = cppr;
+
+ if (cppr <= new_state.pending_pri) {
+ reject = new_state.xisr;
+ new_state.xisr = 0;
+ new_state.pending_pri = 0xff;
+ }
+
+ } while (!icp_try_update(icp, old_state, new_state, true));
+
+ /*
+ * Check for rejects. They are handled by doing a new delivery
+ * attempt (see comments in icp_deliver_irq).
+ */
+ if (reject && reject != XICS_IPI)
+ icp_deliver_irq(xics, icp, reject);
+}
+
+static noinline int h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr)
+{
+ struct kvmppc_xics *xics = vcpu->kvm->arch.xics;
+ struct kvmppc_icp *icp = vcpu->arch.icp;
+ struct kvmppc_ics *ics;
+ struct ics_irq_state *state;
+ u32 irq = xirr & 0x00ffffff;
+ u16 src;
+
+ XICS_DBG("h_eoi vcpu %d eoi %#lx\n", vcpu->vcpu_id, xirr);
+
+ /*
+ * ICP State: EOI
+ *
+ * Note: If EOI is incorrectly used by SW to lower the CPPR
+ * value (ie more favored), we do not check for rejection of
+ * a pending interrupt, this is a SW error and PAPR sepcifies
+ * that we don't have to deal with it.
+ *
+ * The sending of an EOI to the ICS is handled after the
+ * CPPR update
+ *
+ * ICP State: Down_CPPR which we handle
+ * in a separate function as it's shared with H_CPPR.
+ */
+ icp_down_cppr(xics, icp, xirr >> 24);
+
+ /* IPIs have no EOI */
+ if (irq == XICS_IPI)
+ return H_SUCCESS;
+ /*
+ * EOI handling: If the interrupt is still asserted, we need to
+ * resend it. We can take a lockless "peek" at the ICS state here.
+ *
+ * "Message" interrupts will never have "asserted" set
+ */
+ ics = kvmppc_xics_find_ics(xics, irq, &src);
+ if (!ics) {
+ XICS_DBG("h_eoi: IRQ 0x%06x not found !\n", irq);
+ return H_PARAMETER;
+ }
+ state = &ics->irq_state[src];
+
+ /* Still asserted, resend it */
+ if (state->asserted)
+ icp_deliver_irq(xics, icp, irq);
+
+ return H_SUCCESS;
+}
+
+int kvmppc_xics_hcall(struct kvm_vcpu *vcpu, u32 req)
+{
+ unsigned long res;
+ int rc = H_SUCCESS;
+
+ /* Check if we have an ICP */
+ if (!vcpu->arch.icp || !vcpu->kvm->arch.xics)
+ return H_HARDWARE;
+
+ switch (req) {
+ case H_XIRR:
+ res = h_xirr(vcpu);
+ kvmppc_set_gpr(vcpu, 4, res);
+ break;
+ case H_CPPR:
+ h_cppr(vcpu, kvmppc_get_gpr(vcpu, 4));
+ break;
+ case H_EOI:
+ rc = h_eoi(vcpu, kvmppc_get_gpr(vcpu, 4));
+ break;
+ case H_IPI:
+ rc = h_ipi(vcpu, kvmppc_get_gpr(vcpu, 4),
+ kvmppc_get_gpr(vcpu, 5));
+ break;
+ }
+
+ return rc;
+}
+
+
+/* -- Initialisation code etc. -- */
+
+static int xics_debug_show(struct seq_file *m, void *private)
+{
+ struct kvmppc_xics *xics = m->private;
+ struct kvm *kvm = xics->kvm;
+ struct kvm_vcpu *vcpu;
+ int icsid, i;
+
+ if (!kvm)
+ return 0;
+
+ seq_printf(m, "=========\nICP state\n=========\n");
+
+ kvm_for_each_vcpu(i, vcpu, kvm) {
+ struct kvmppc_icp *icp = vcpu->arch.icp;
+ union kvmppc_icp_state state;
+
+ if (!icp)
+ continue;
+
+ state.raw = ACCESS_ONCE(icp->state.raw);
+ seq_printf(m, "cpu server %#x XIRR:%#x PPRI:%#x CPPR:%#x "
+ "MFRR:%#x OUT:%d NR:%d\n", vcpu->vcpu_id, state.xisr,
+ state.pending_pri, state.cppr, state.mfrr,
+ state.out_ee, state.need_resend);
+ }
+
+ for (icsid = 0; icsid <= KVMPPC_XICS_MAX_ICS_ID; icsid++) {
+ struct kvmppc_ics *ics = xics->ics[icsid];
+
+ if (!ics)
+ continue;
+
+ seq_printf(m, "=========\nICS state for ICS 0x%x\n=========\n",
+ icsid);
+
+ mutex_lock(&ics->lock);
+
+ for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) {
+ struct ics_irq_state *irq = &ics->irq_state[i];
+
+ seq_printf(m, "irq 0x%06x: server %#x prio %#x save"
+ " prio %#x asserted %d resend %d masked"
+ " pending %d\n",
+ irq->number, irq->server, irq->priority,
+ irq->saved_priority, irq->asserted,
+ irq->resend, irq->masked_pending);
+
+ }
+ mutex_unlock(&ics->lock);
+ }
+ return 0;
+}
+
+static int xics_debug_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, xics_debug_show, inode->i_private);
+}
+
+static const struct file_operations xics_debug_fops = {
+ .open = xics_debug_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static void xics_debugfs_init(struct kvmppc_xics *xics)
+{
+ char *name;
+
+ name = kasprintf(GFP_KERNEL, "kvm-xics-%p", xics);
+ if (!name) {
+ pr_err("%s: no memory for name\n", __func__);
+ return;
+ }
+
+ xics->dentry = debugfs_create_file(name, S_IRUGO, powerpc_debugfs_root,
+ xics, &xics_debug_fops);
+
+ pr_debug("%s: created %s\n", __func__, name);
+ kfree(name);
+}
+
+struct kvmppc_ics *kvmppc_xics_create_ics(struct kvmppc_xics *xics,
+ int irq)
+{
+ struct kvmppc_ics *ics;
+ int i, icsid;
+
+ icsid = irq >> KVMPPC_XICS_ICS_SHIFT;
+
+ mutex_lock(&xics->kvm->lock);
+
+ /* ICS already exists - somebody else got here first */
+ if (xics->ics[icsid])
+ goto out;
+
+ /* Create the ICS */
+ ics = kzalloc(sizeof(struct kvmppc_ics), GFP_KERNEL);
+ if (!ics)
+ goto out;
+
+ mutex_init(&ics->lock);
+ ics->icsid = icsid;
+
+ for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) {
+ ics->irq_state[i].number = (icsid << KVMPPC_XICS_ICS_SHIFT) | i;
+ ics->irq_state[i].priority = MASKED;
+ ics->irq_state[i].saved_priority = MASKED;
+ }
+ smp_wmb();
+ xics->ics[icsid] = ics;
+
+ if (icsid > xics->max_icsid)
+ xics->max_icsid = icsid;
+
+ out:
+ mutex_unlock(&xics->kvm->lock);
+ return xics->ics[icsid];
+}
+
+int kvmppc_xics_create_icp(struct kvm_vcpu *vcpu, unsigned long server_num)
+{
+ struct kvmppc_icp *icp;
+
+ if (!vcpu->kvm->arch.xics)
+ return -ENODEV;
+
+ if (kvmppc_xics_find_server(vcpu->kvm, server_num))
+ return -EEXIST;
+
+ icp = kzalloc(sizeof(struct kvmppc_icp), GFP_KERNEL);
+ if (!icp)
+ return -ENOMEM;
+
+ icp->vcpu = vcpu;
+ icp->server_num = server_num;
+ icp->state.mfrr = MASKED;
+ icp->state.pending_pri = MASKED;
+ vcpu->arch.icp = icp;
+
+ XICS_DBG("created server for vcpu %d\n", vcpu->vcpu_id);
+
+ return 0;
+}
+
+/* -- ioctls -- */
+
+int kvm_vm_ioctl_xics_irq(struct kvm *kvm, struct kvm_irq_level *args)
+{
+ struct kvmppc_xics *xics;
+ int r;
+
+ /* locking against multiple callers? */
+
+ xics = kvm->arch.xics;
+ if (!xics)
+ return -ENODEV;
+
+ switch (args->level) {
+ case KVM_INTERRUPT_SET:
+ case KVM_INTERRUPT_SET_LEVEL:
+ case KVM_INTERRUPT_UNSET:
+ r = ics_deliver_irq(xics, args->irq, args->level);
+ break;
+ default:
+ r = -EINVAL;
+ }
+
+ return r;
+}
+
+void kvmppc_xics_free(struct kvmppc_xics *xics)
+{
+ int i;
+
+ debugfs_remove(xics->dentry);
+
+ if (xics->kvm) {
+ kvm_put_kvm(xics->kvm);
+ xics->kvm->arch.xics = NULL;
+ xics->kvm = NULL;
+ }
+
+ for (i = 0; i <= xics->max_icsid; i++) {
+ if (xics->ics[i])
+ kfree(xics->ics[i]);
+ }
+ kfree(xics);
+}
+
+int kvm_create_xics(struct kvm *kvm, u32 type)
+{
+ struct kvmppc_xics *xics;
+
+ /* Already there ? */
+ if (kvm->arch.xics)
+ return -EEXIST;
+
+ xics = kzalloc(sizeof(*xics), GFP_KERNEL);
+ if (!xics)
+ return -ENOMEM;
+
+ xics->kvm = kvm;
+ kvm->arch.xics = xics;
+ xics_debugfs_init(xics);
+
+ kvm_get_kvm(kvm);
+ return 0;
+}
+
+void kvmppc_xics_free_icp(struct kvm_vcpu *vcpu)
+{
+ if (!vcpu->arch.icp)
+ return;
+ kfree(vcpu->arch.icp);
+ vcpu->arch.icp = NULL;
+ vcpu->arch.irq_type = KVMPPC_IRQ_DEFAULT;
+}
new file mode 100644
@@ -0,0 +1,113 @@
+/*
+ * Copyright 2012 Michael Ellerman, IBM Corporation.
+ * Copyright 2012 Benjamin Herrenschmidt, IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _KVM_PPC_BOOK3S_XICS_H
+#define _KVM_PPC_BOOK3S_XICS_H
+
+/*
+ * We use a two-level tree to store interrupt source information.
+ * There are up to 1024 ICS nodes, each of which can represent
+ * 1024 sources.
+ */
+#define KVMPPC_XICS_MAX_ICS_ID 1023
+#define KVMPPC_XICS_ICS_SHIFT 10
+#define KVMPPC_XICS_IRQ_PER_ICS (1 << KVMPPC_XICS_ICS_SHIFT)
+#define KVMPPC_XICS_SRC_MASK (KVMPPC_XICS_IRQ_PER_ICS - 1)
+
+/*
+ * Interrupt source numbers below this are reserved, for example
+ * 0 is "no interrupt", and 2 is used for IPIs.
+ */
+#define KVMPPC_XICS_FIRST_IRQ 16
+#define KVMPPC_XICS_NR_IRQS ((KVMPPC_XICS_MAX_ICS_ID + 1) * KVMPPC_XICS_IRQ_PER_ICS)
+
+/* Priority value to use for disabling an interrupt */
+#define MASKED 0xff
+
+/* State for one irq source */
+struct ics_irq_state {
+ u32 number;
+ u32 server;
+ u8 priority;
+ u8 saved_priority; /* currently unused */
+ u8 resend;
+ u8 masked_pending;
+ u8 asserted; /* Only for LSI */
+ u8 exists;
+};
+
+/* Atomic ICP state, updated with a single compare & swap */
+union kvmppc_icp_state {
+ unsigned long raw;
+ struct {
+ u8 out_ee : 1;
+ u8 need_resend : 1;
+ u8 cppr;
+ u8 mfrr;
+ u8 pending_pri;
+ u32 xisr;
+ };
+};
+
+/* One bit per ICS */
+#define ICP_RESEND_MAP_SIZE (KVMPPC_XICS_MAX_ICS_ID / BITS_PER_LONG + 1)
+
+struct kvmppc_icp {
+ struct kvm_vcpu *vcpu;
+ unsigned long server_num;
+ union kvmppc_icp_state state;
+ unsigned long resend_map[ICP_RESEND_MAP_SIZE];
+};
+
+struct kvmppc_ics {
+ struct mutex lock;
+ u16 icsid;
+ struct ics_irq_state irq_state[KVMPPC_XICS_IRQ_PER_ICS];
+};
+
+struct kvmppc_xics {
+ struct kvm *kvm;
+ struct dentry *dentry;
+ u32 max_icsid;
+ atomic_t usecount;
+ struct kvmppc_ics *ics[KVMPPC_XICS_MAX_ICS_ID + 1];
+};
+
+static inline struct kvmppc_icp *kvmppc_xics_find_server(struct kvm *kvm,
+ u32 nr)
+{
+ struct kvm_vcpu *vcpu = NULL;
+ int i;
+
+ kvm_for_each_vcpu(i, vcpu, kvm) {
+ if (vcpu->arch.icp && nr == vcpu->arch.icp->server_num)
+ return vcpu->arch.icp;
+ }
+ return NULL;
+}
+
+static inline struct kvmppc_ics *kvmppc_xics_find_ics(struct kvmppc_xics *xics,
+ u32 irq, u16 *source)
+{
+ u32 icsid = irq >> KVMPPC_XICS_ICS_SHIFT;
+ u16 src = irq & KVMPPC_XICS_SRC_MASK;
+ struct kvmppc_ics *ics;
+
+ if (source)
+ *source = src;
+ if (icsid > KVMPPC_XICS_MAX_ICS_ID)
+ return NULL;
+ ics = xics->ics[icsid];
+ if (!ics)
+ return NULL;
+ return ics;
+}
+
+
+#endif /* _KVM_PPC_BOOK3S_XICS_H */
@@ -472,6 +472,11 @@ void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
kvmppc_mpic_put(vcpu->arch.mpic);
break;
#endif
+#ifdef CONFIG_KVM_XICS
+ case KVMPPC_IRQ_XICS:
+ kvmppc_xics_free_icp(vcpu);
+ break;
+#endif
default:
break;
}