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-rw-r--r--arch/powerpc/kvm/book3s_hv_rm_xics.c923
1 files changed, 923 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_hv_rm_xics.c b/arch/powerpc/kvm/book3s_hv_rm_xics.c
new file mode 100644
index 000000000..aaafb9f08
--- /dev/null
+++ b/arch/powerpc/kvm/book3s_hv_rm_xics.c
@@ -0,0 +1,923 @@
+/*
+ * 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/kernel_stat.h>
+
+#include <asm/kvm_book3s.h>
+#include <asm/kvm_ppc.h>
+#include <asm/hvcall.h>
+#include <asm/xics.h>
+#include <asm/synch.h>
+#include <asm/cputhreads.h>
+#include <asm/pgtable.h>
+#include <asm/ppc-opcode.h>
+#include <asm/pnv-pci.h>
+#include <asm/opal.h>
+#include <asm/smp.h>
+
+#include "book3s_xics.h"
+
+#define DEBUG_PASSUP
+
+int h_ipi_redirect = 1;
+EXPORT_SYMBOL(h_ipi_redirect);
+int kvm_irq_bypass = 1;
+EXPORT_SYMBOL(kvm_irq_bypass);
+
+static void icp_rm_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp,
+ u32 new_irq, bool check_resend);
+static int xics_opal_set_server(unsigned int hw_irq, int server_cpu);
+
+/* -- ICS routines -- */
+static void ics_rm_check_resend(struct kvmppc_xics *xics,
+ struct kvmppc_ics *ics, struct kvmppc_icp *icp)
+{
+ int i;
+
+ for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) {
+ struct ics_irq_state *state = &ics->irq_state[i];
+ if (state->resend)
+ icp_rm_deliver_irq(xics, icp, state->number, true);
+ }
+
+}
+
+/* -- ICP routines -- */
+
+#ifdef CONFIG_SMP
+static inline void icp_send_hcore_msg(int hcore, struct kvm_vcpu *vcpu)
+{
+ int hcpu;
+
+ hcpu = hcore << threads_shift;
+ kvmppc_host_rm_ops_hv->rm_core[hcore].rm_data = vcpu;
+ smp_muxed_ipi_set_message(hcpu, PPC_MSG_RM_HOST_ACTION);
+ kvmppc_set_host_ipi(hcpu);
+ smp_mb();
+ kvmhv_rm_send_ipi(hcpu);
+}
+#else
+static inline void icp_send_hcore_msg(int hcore, struct kvm_vcpu *vcpu) { }
+#endif
+
+/*
+ * We start the search from our current CPU Id in the core map
+ * and go in a circle until we get back to our ID looking for a
+ * core that is running in host context and that hasn't already
+ * been targeted for another rm_host_ops.
+ *
+ * In the future, could consider using a fairer algorithm (one
+ * that distributes the IPIs better)
+ *
+ * Returns -1, if no CPU could be found in the host
+ * Else, returns a CPU Id which has been reserved for use
+ */
+static inline int grab_next_hostcore(int start,
+ struct kvmppc_host_rm_core *rm_core, int max, int action)
+{
+ bool success;
+ int core;
+ union kvmppc_rm_state old, new;
+
+ for (core = start + 1; core < max; core++) {
+ old = new = READ_ONCE(rm_core[core].rm_state);
+
+ if (!old.in_host || old.rm_action)
+ continue;
+
+ /* Try to grab this host core if not taken already. */
+ new.rm_action = action;
+
+ success = cmpxchg64(&rm_core[core].rm_state.raw,
+ old.raw, new.raw) == old.raw;
+ if (success) {
+ /*
+ * Make sure that the store to the rm_action is made
+ * visible before we return to caller (and the
+ * subsequent store to rm_data) to synchronize with
+ * the IPI handler.
+ */
+ smp_wmb();
+ return core;
+ }
+ }
+
+ return -1;
+}
+
+static inline int find_available_hostcore(int action)
+{
+ int core;
+ int my_core = smp_processor_id() >> threads_shift;
+ struct kvmppc_host_rm_core *rm_core = kvmppc_host_rm_ops_hv->rm_core;
+
+ core = grab_next_hostcore(my_core, rm_core, cpu_nr_cores(), action);
+ if (core == -1)
+ core = grab_next_hostcore(core, rm_core, my_core, action);
+
+ return core;
+}
+
+static void icp_rm_set_vcpu_irq(struct kvm_vcpu *vcpu,
+ struct kvm_vcpu *this_vcpu)
+{
+ struct kvmppc_icp *this_icp = this_vcpu->arch.icp;
+ int cpu;
+ int hcore;
+
+ /* Mark the target VCPU as having an interrupt pending */
+ vcpu->stat.queue_intr++;
+ set_bit(BOOK3S_IRQPRIO_EXTERNAL_LEVEL, &vcpu->arch.pending_exceptions);
+
+ /* Kick self ? Just set MER and return */
+ if (vcpu == this_vcpu) {
+ mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) | LPCR_MER);
+ return;
+ }
+
+ /*
+ * Check if the core is loaded,
+ * if not, find an available host core to post to wake the VCPU,
+ * if we can't find one, set up state to eventually return too hard.
+ */
+ cpu = vcpu->arch.thread_cpu;
+ if (cpu < 0 || cpu >= nr_cpu_ids) {
+ hcore = -1;
+ if (kvmppc_host_rm_ops_hv && h_ipi_redirect)
+ hcore = find_available_hostcore(XICS_RM_KICK_VCPU);
+ if (hcore != -1) {
+ icp_send_hcore_msg(hcore, vcpu);
+ } else {
+ this_icp->rm_action |= XICS_RM_KICK_VCPU;
+ this_icp->rm_kick_target = vcpu;
+ }
+ return;
+ }
+
+ smp_mb();
+ kvmhv_rm_send_ipi(cpu);
+}
+
+static void icp_rm_clr_vcpu_irq(struct kvm_vcpu *vcpu)
+{
+ /* Note: Only called on self ! */
+ clear_bit(BOOK3S_IRQPRIO_EXTERNAL_LEVEL,
+ &vcpu->arch.pending_exceptions);
+ mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) & ~LPCR_MER);
+}
+
+static inline bool icp_rm_try_update(struct kvmppc_icp *icp,
+ union kvmppc_icp_state old,
+ union kvmppc_icp_state new)
+{
+ struct kvm_vcpu *this_vcpu = local_paca->kvm_hstate.kvm_vcpu;
+ 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;
+
+ /*
+ * 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. The reason
+ * for that is that we opportunistically remove the pending interrupt
+ * flag when raising CPPR, so we need to set it back here if an
+ * interrupt is still pending.
+ */
+ if (new.out_ee)
+ icp_rm_set_vcpu_irq(icp->vcpu, this_vcpu);
+
+ /* Expose the state change for debug purposes */
+ this_vcpu->arch.icp->rm_dbgstate = new;
+ this_vcpu->arch.icp->rm_dbgtgt = icp->vcpu;
+
+ bail:
+ return success;
+}
+
+static inline int check_too_hard(struct kvmppc_xics *xics,
+ struct kvmppc_icp *icp)
+{
+ return (xics->real_mode_dbg || icp->rm_action) ? H_TOO_HARD : H_SUCCESS;
+}
+
+static void icp_rm_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_rm_check_resend(xics, ics, icp);
+ }
+}
+
+static bool icp_rm_try_to_deliver(struct kvmppc_icp *icp, u32 irq, u8 priority,
+ u32 *reject)
+{
+ union kvmppc_icp_state old_state, new_state;
+ bool success;
+
+ do {
+ old_state = new_state = READ_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_rm_try_update(icp, old_state, new_state));
+
+ return success;
+}
+
+static void icp_rm_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp,
+ u32 new_irq, bool check_resend)
+{
+ 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) {
+ /* Unsafe increment, but this does not need to be accurate */
+ xics->err_noics++;
+ return;
+ }
+ state = &ics->irq_state[src];
+
+ /* Get a lock on the ICS */
+ arch_spin_lock(&ics->lock);
+
+ /* Get our server */
+ if (!icp || state->server != icp->server_num) {
+ icp = kvmppc_xics_find_server(xics->kvm, state->server);
+ if (!icp) {
+ /* Unsafe increment again*/
+ xics->err_noicp++;
+ goto out;
+ }
+ }
+
+ if (check_resend)
+ if (!state->resend)
+ 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 differentiate normal deliveries and resends, this
+ * implementation will differ from PAPR and not lose such
+ * interrupts.
+ */
+ if (state->priority == MASKED) {
+ 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
+ * ics spin lock.
+ *
+ * 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_rm_try_to_deliver() the target
+ * processor may well have already consumed & completed it, and thus
+ * the rejected interrupt might actually be already acceptable.
+ */
+ if (icp_rm_try_to_deliver(icp, new_irq, state->priority, &reject)) {
+ /*
+ * Delivery was successful, did we reject somebody else ?
+ */
+ if (reject && reject != XICS_IPI) {
+ arch_spin_unlock(&ics->lock);
+ icp->n_reject++;
+ new_irq = reject;
+ check_resend = 0;
+ 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
+ */
+ state->resend = 1;
+
+ /*
+ * Make sure when checking resend, we don't miss the resend
+ * if resend_map bit is seen and cleared.
+ */
+ smp_wmb();
+ set_bit(ics->icsid, icp->resend_map);
+
+ /*
+ * If the need_resend flag got cleared in the ICP some time
+ * between icp_rm_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) {
+ state->resend = 0;
+ arch_spin_unlock(&ics->lock);
+ check_resend = 0;
+ goto again;
+ }
+ }
+ out:
+ arch_spin_unlock(&ics->lock);
+}
+
+static void icp_rm_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 = READ_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) {
+ 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_rm_try_update(icp, old_state, new_state));
+
+ /*
+ * Now handle resend checks. Those are asynchronous to the ICP
+ * state update in HW (ie bus transactions) so we can handle them
+ * separately here as well.
+ */
+ if (resend) {
+ icp->n_check_resend++;
+ icp_rm_check_resend(xics, icp);
+ }
+}
+
+
+unsigned long xics_rm_h_xirr(struct kvm_vcpu *vcpu)
+{
+ union kvmppc_icp_state old_state, new_state;
+ struct kvmppc_xics *xics = vcpu->kvm->arch.xics;
+ struct kvmppc_icp *icp = vcpu->arch.icp;
+ u32 xirr;
+
+ if (!xics || !xics->real_mode)
+ return H_TOO_HARD;
+
+ /* First clear the interrupt */
+ icp_rm_clr_vcpu_irq(icp->vcpu);
+
+ /*
+ * 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 = READ_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_rm_try_update(icp, old_state, new_state));
+
+ /* Return the result in GPR4 */
+ vcpu->arch.regs.gpr[4] = xirr;
+
+ return check_too_hard(xics, icp);
+}
+
+int xics_rm_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, *this_icp = vcpu->arch.icp;
+ u32 reject;
+ bool resend;
+ bool local;
+
+ if (!xics || !xics->real_mode)
+ return H_TOO_HARD;
+
+ local = this_icp->server_num == server;
+ if (local)
+ icp = this_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 done as there can be no XISR to
+ * reject.
+ *
+ * ICP state: Check_IPI
+ *
+ * If the CPPR is less favored, then we might be replacing
+ * an interrupt, and thus need to possibly reject it.
+ *
+ * ICP State: IPI
+ *
+ * Besides rejecting any pending interrupts, we also
+ * update XISR and pending_pri to mark IPI as pending.
+ *
+ * PAPR does not describe this state, but if the MFRR is being
+ * made less favored than its earlier value, there might be
+ * a previously-rejected interrupt needing to be resent.
+ * Ideally, we would want to resend only if
+ * prio(pending_interrupt) < mfrr &&
+ * prio(pending_interrupt) < cppr
+ * where pending interrupt is the one that was rejected. But
+ * we don't have that state, so we simply trigger a resend
+ * whenever the MFRR is made less favored.
+ */
+ do {
+ old_state = new_state = READ_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) {
+ resend = new_state.need_resend;
+ new_state.need_resend = 0;
+ }
+ } while (!icp_rm_try_update(icp, old_state, new_state));
+
+ /* Handle reject in real mode */
+ if (reject && reject != XICS_IPI) {
+ this_icp->n_reject++;
+ icp_rm_deliver_irq(xics, icp, reject, false);
+ }
+
+ /* Handle resends in real mode */
+ if (resend) {
+ this_icp->n_check_resend++;
+ icp_rm_check_resend(xics, icp);
+ }
+
+ return check_too_hard(xics, this_icp);
+}
+
+int xics_rm_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;
+
+ if (!xics || !xics->real_mode)
+ return H_TOO_HARD;
+
+ /*
+ * 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_rm_down_cppr(xics, icp, cppr);
+ goto bail;
+ } else if (cppr == icp->state.cppr)
+ return H_SUCCESS;
+
+ /*
+ * 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
+ */
+ icp_rm_clr_vcpu_irq(icp->vcpu);
+
+ do {
+ old_state = new_state = READ_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_rm_try_update(icp, old_state, new_state));
+
+ /*
+ * Check for rejects. They are handled by doing a new delivery
+ * attempt (see comments in icp_rm_deliver_irq).
+ */
+ if (reject && reject != XICS_IPI) {
+ icp->n_reject++;
+ icp_rm_deliver_irq(xics, icp, reject, false);
+ }
+ bail:
+ return check_too_hard(xics, icp);
+}
+
+static int ics_rm_eoi(struct kvm_vcpu *vcpu, u32 irq)
+{
+ struct kvmppc_xics *xics = vcpu->kvm->arch.xics;
+ struct kvmppc_icp *icp = vcpu->arch.icp;
+ struct kvmppc_ics *ics;
+ struct ics_irq_state *state;
+ u16 src;
+ u32 pq_old, pq_new;
+
+ /*
+ * ICS EOI handling: For LSI, if P bit is still set, we need to
+ * resend it.
+ *
+ * For MSI, we move Q bit into P (and clear Q). If it is set,
+ * resend it.
+ */
+
+ ics = kvmppc_xics_find_ics(xics, irq, &src);
+ if (!ics)
+ goto bail;
+
+ state = &ics->irq_state[src];
+
+ if (state->lsi)
+ pq_new = state->pq_state;
+ else
+ do {
+ pq_old = state->pq_state;
+ pq_new = pq_old >> 1;
+ } while (cmpxchg(&state->pq_state, pq_old, pq_new) != pq_old);
+
+ if (pq_new & PQ_PRESENTED)
+ icp_rm_deliver_irq(xics, NULL, irq, false);
+
+ if (!hlist_empty(&vcpu->kvm->irq_ack_notifier_list)) {
+ icp->rm_action |= XICS_RM_NOTIFY_EOI;
+ icp->rm_eoied_irq = irq;
+ }
+
+ if (state->host_irq) {
+ ++vcpu->stat.pthru_all;
+ if (state->intr_cpu != -1) {
+ int pcpu = raw_smp_processor_id();
+
+ pcpu = cpu_first_thread_sibling(pcpu);
+ ++vcpu->stat.pthru_host;
+ if (state->intr_cpu != pcpu) {
+ ++vcpu->stat.pthru_bad_aff;
+ xics_opal_set_server(state->host_irq, pcpu);
+ }
+ state->intr_cpu = -1;
+ }
+ }
+
+ bail:
+ return check_too_hard(xics, icp);
+}
+
+int xics_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr)
+{
+ struct kvmppc_xics *xics = vcpu->kvm->arch.xics;
+ struct kvmppc_icp *icp = vcpu->arch.icp;
+ u32 irq = xirr & 0x00ffffff;
+
+ if (!xics || !xics->real_mode)
+ return H_TOO_HARD;
+
+ /*
+ * 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 specifies
+ * 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_rm_down_cppr(xics, icp, xirr >> 24);
+
+ /* IPIs have no EOI */
+ if (irq == XICS_IPI)
+ return check_too_hard(xics, icp);
+
+ return ics_rm_eoi(vcpu, irq);
+}
+
+unsigned long eoi_rc;
+
+static void icp_eoi(struct irq_chip *c, u32 hwirq, __be32 xirr, bool *again)
+{
+ void __iomem *xics_phys;
+ int64_t rc;
+
+ rc = pnv_opal_pci_msi_eoi(c, hwirq);
+
+ if (rc)
+ eoi_rc = rc;
+
+ iosync();
+
+ /* EOI it */
+ xics_phys = local_paca->kvm_hstate.xics_phys;
+ if (xics_phys) {
+ __raw_rm_writel(xirr, xics_phys + XICS_XIRR);
+ } else {
+ rc = opal_int_eoi(be32_to_cpu(xirr));
+ *again = rc > 0;
+ }
+}
+
+static int xics_opal_set_server(unsigned int hw_irq, int server_cpu)
+{
+ unsigned int mangle_cpu = get_hard_smp_processor_id(server_cpu) << 2;
+
+ return opal_set_xive(hw_irq, mangle_cpu, DEFAULT_PRIORITY);
+}
+
+/*
+ * Increment a per-CPU 32-bit unsigned integer variable.
+ * Safe to call in real-mode. Handles vmalloc'ed addresses
+ *
+ * ToDo: Make this work for any integral type
+ */
+
+static inline void this_cpu_inc_rm(unsigned int __percpu *addr)
+{
+ unsigned long l;
+ unsigned int *raddr;
+ int cpu = smp_processor_id();
+
+ raddr = per_cpu_ptr(addr, cpu);
+ l = (unsigned long)raddr;
+
+ if (REGION_ID(l) == VMALLOC_REGION_ID) {
+ l = vmalloc_to_phys(raddr);
+ raddr = (unsigned int *)l;
+ }
+ ++*raddr;
+}
+
+/*
+ * We don't try to update the flags in the irq_desc 'istate' field in
+ * here as would happen in the normal IRQ handling path for several reasons:
+ * - state flags represent internal IRQ state and are not expected to be
+ * updated outside the IRQ subsystem
+ * - more importantly, these are useful for edge triggered interrupts,
+ * IRQ probing, etc., but we are only handling MSI/MSIx interrupts here
+ * and these states shouldn't apply to us.
+ *
+ * However, we do update irq_stats - we somewhat duplicate the code in
+ * kstat_incr_irqs_this_cpu() for this since this function is defined
+ * in irq/internal.h which we don't want to include here.
+ * The only difference is that desc->kstat_irqs is an allocated per CPU
+ * variable and could have been vmalloc'ed, so we can't directly
+ * call __this_cpu_inc() on it. The kstat structure is a static
+ * per CPU variable and it should be accessible by real-mode KVM.
+ *
+ */
+static void kvmppc_rm_handle_irq_desc(struct irq_desc *desc)
+{
+ this_cpu_inc_rm(desc->kstat_irqs);
+ __this_cpu_inc(kstat.irqs_sum);
+}
+
+long kvmppc_deliver_irq_passthru(struct kvm_vcpu *vcpu,
+ __be32 xirr,
+ struct kvmppc_irq_map *irq_map,
+ struct kvmppc_passthru_irqmap *pimap,
+ bool *again)
+{
+ struct kvmppc_xics *xics;
+ struct kvmppc_icp *icp;
+ struct kvmppc_ics *ics;
+ struct ics_irq_state *state;
+ u32 irq;
+ u16 src;
+ u32 pq_old, pq_new;
+
+ irq = irq_map->v_hwirq;
+ xics = vcpu->kvm->arch.xics;
+ icp = vcpu->arch.icp;
+
+ kvmppc_rm_handle_irq_desc(irq_map->desc);
+
+ ics = kvmppc_xics_find_ics(xics, irq, &src);
+ if (!ics)
+ return 2;
+
+ state = &ics->irq_state[src];
+
+ /* only MSIs register bypass producers, so it must be MSI here */
+ do {
+ pq_old = state->pq_state;
+ pq_new = ((pq_old << 1) & 3) | PQ_PRESENTED;
+ } while (cmpxchg(&state->pq_state, pq_old, pq_new) != pq_old);
+
+ /* Test P=1, Q=0, this is the only case where we present */
+ if (pq_new == PQ_PRESENTED)
+ icp_rm_deliver_irq(xics, icp, irq, false);
+
+ /* EOI the interrupt */
+ icp_eoi(irq_desc_get_chip(irq_map->desc), irq_map->r_hwirq, xirr,
+ again);
+
+ if (check_too_hard(xics, icp) == H_TOO_HARD)
+ return 2;
+ else
+ return -2;
+}
+
+/* --- Non-real mode XICS-related built-in routines --- */
+
+/**
+ * Host Operations poked by RM KVM
+ */
+static void rm_host_ipi_action(int action, void *data)
+{
+ switch (action) {
+ case XICS_RM_KICK_VCPU:
+ kvmppc_host_rm_ops_hv->vcpu_kick(data);
+ break;
+ default:
+ WARN(1, "Unexpected rm_action=%d data=%p\n", action, data);
+ break;
+ }
+
+}
+
+void kvmppc_xics_ipi_action(void)
+{
+ int core;
+ unsigned int cpu = smp_processor_id();
+ struct kvmppc_host_rm_core *rm_corep;
+
+ core = cpu >> threads_shift;
+ rm_corep = &kvmppc_host_rm_ops_hv->rm_core[core];
+
+ if (rm_corep->rm_data) {
+ rm_host_ipi_action(rm_corep->rm_state.rm_action,
+ rm_corep->rm_data);
+ /* Order these stores against the real mode KVM */
+ rm_corep->rm_data = NULL;
+ smp_wmb();
+ rm_corep->rm_state.rm_action = 0;
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-21 21:35:25 +0000