diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_xive_template.c')
| -rw-r--r-- | arch/powerpc/kvm/book3s_xive_template.c | 636 |
1 files changed, 0 insertions, 636 deletions
diff --git a/arch/powerpc/kvm/book3s_xive_template.c b/arch/powerpc/kvm/book3s_xive_template.c deleted file mode 100644 index b0015e05d99a..000000000000 --- a/arch/powerpc/kvm/book3s_xive_template.c +++ /dev/null @@ -1,636 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Copyright 2017 Benjamin Herrenschmidt, IBM Corporation - */ - -/* File to be included by other .c files */ - -#define XGLUE(a,b) a##b -#define GLUE(a,b) XGLUE(a,b) - -/* Dummy interrupt used when taking interrupts out of a queue in H_CPPR */ -#define XICS_DUMMY 1 - -static void GLUE(X_PFX,ack_pending)(struct kvmppc_xive_vcpu *xc) -{ - u8 cppr; - u16 ack; - - /* - * Ensure any previous store to CPPR is ordered vs. - * the subsequent loads from PIPR or ACK. - */ - eieio(); - - /* Perform the acknowledge OS to register cycle. */ - ack = be16_to_cpu(__x_readw(__x_tima + TM_SPC_ACK_OS_REG)); - - /* Synchronize subsequent queue accesses */ - mb(); - - /* XXX Check grouping level */ - - /* Anything ? */ - if (!((ack >> 8) & TM_QW1_NSR_EO)) - return; - - /* Grab CPPR of the most favored pending interrupt */ - cppr = ack & 0xff; - if (cppr < 8) - xc->pending |= 1 << cppr; - -#ifdef XIVE_RUNTIME_CHECKS - /* Check consistency */ - if (cppr >= xc->hw_cppr) - pr_warn("KVM-XIVE: CPU %d odd ack CPPR, got %d at %d\n", - smp_processor_id(), cppr, xc->hw_cppr); -#endif - - /* - * Update our image of the HW CPPR. We don't yet modify - * xc->cppr, this will be done as we scan for interrupts - * in the queues. - */ - xc->hw_cppr = cppr; -} - -static u8 GLUE(X_PFX,esb_load)(struct xive_irq_data *xd, u32 offset) -{ - u64 val; - - if (offset == XIVE_ESB_SET_PQ_10 && xd->flags & XIVE_IRQ_FLAG_STORE_EOI) - offset |= XIVE_ESB_LD_ST_MO; - - val =__x_readq(__x_eoi_page(xd) + offset); -#ifdef __LITTLE_ENDIAN__ - val >>= 64-8; -#endif - return (u8)val; -} - - -static void GLUE(X_PFX,source_eoi)(u32 hw_irq, struct xive_irq_data *xd) -{ - /* If the XIVE supports the new "store EOI facility, use it */ - if (xd->flags & XIVE_IRQ_FLAG_STORE_EOI) - __x_writeq(0, __x_eoi_page(xd) + XIVE_ESB_STORE_EOI); - else if (xd->flags & XIVE_IRQ_FLAG_LSI) { - /* - * For LSIs the HW EOI cycle is used rather than PQ bits, - * as they are automatically re-triggred in HW when still - * pending. - */ - __x_readq(__x_eoi_page(xd) + XIVE_ESB_LOAD_EOI); - } else { - uint64_t eoi_val; - - /* - * Otherwise for EOI, we use the special MMIO that does - * a clear of both P and Q and returns the old Q, - * except for LSIs where we use the "EOI cycle" special - * load. - * - * This allows us to then do a re-trigger if Q was set - * rather than synthetizing an interrupt in software - */ - eoi_val = GLUE(X_PFX,esb_load)(xd, XIVE_ESB_SET_PQ_00); - - /* Re-trigger if needed */ - if ((eoi_val & 1) && __x_trig_page(xd)) - __x_writeq(0, __x_trig_page(xd)); - } -} - -enum { - scan_fetch, - scan_poll, - scan_eoi, -}; - -static u32 GLUE(X_PFX,scan_interrupts)(struct kvmppc_xive_vcpu *xc, - u8 pending, int scan_type) -{ - u32 hirq = 0; - u8 prio = 0xff; - - /* Find highest pending priority */ - while ((xc->mfrr != 0xff || pending != 0) && hirq == 0) { - struct xive_q *q; - u32 idx, toggle; - __be32 *qpage; - - /* - * If pending is 0 this will return 0xff which is what - * we want - */ - prio = ffs(pending) - 1; - - /* Don't scan past the guest cppr */ - if (prio >= xc->cppr || prio > 7) { - if (xc->mfrr < xc->cppr) { - prio = xc->mfrr; - hirq = XICS_IPI; - } - break; - } - - /* Grab queue and pointers */ - q = &xc->queues[prio]; - idx = q->idx; - toggle = q->toggle; - - /* - * Snapshot the queue page. The test further down for EOI - * must use the same "copy" that was used by __xive_read_eq - * since qpage can be set concurrently and we don't want - * to miss an EOI. - */ - qpage = READ_ONCE(q->qpage); - -skip_ipi: - /* - * Try to fetch from the queue. Will return 0 for a - * non-queueing priority (ie, qpage = 0). - */ - hirq = __xive_read_eq(qpage, q->msk, &idx, &toggle); - - /* - * If this was a signal for an MFFR change done by - * H_IPI we skip it. Additionally, if we were fetching - * we EOI it now, thus re-enabling reception of a new - * such signal. - * - * We also need to do that if prio is 0 and we had no - * page for the queue. In this case, we have non-queued - * IPI that needs to be EOId. - * - * This is safe because if we have another pending MFRR - * change that wasn't observed above, the Q bit will have - * been set and another occurrence of the IPI will trigger. - */ - if (hirq == XICS_IPI || (prio == 0 && !qpage)) { - if (scan_type == scan_fetch) { - GLUE(X_PFX,source_eoi)(xc->vp_ipi, - &xc->vp_ipi_data); - q->idx = idx; - q->toggle = toggle; - } - /* Loop back on same queue with updated idx/toggle */ -#ifdef XIVE_RUNTIME_CHECKS - WARN_ON(hirq && hirq != XICS_IPI); -#endif - if (hirq) - goto skip_ipi; - } - - /* If it's the dummy interrupt, continue searching */ - if (hirq == XICS_DUMMY) - goto skip_ipi; - - /* Clear the pending bit if the queue is now empty */ - if (!hirq) { - pending &= ~(1 << prio); - - /* - * Check if the queue count needs adjusting due to - * interrupts being moved away. - */ - if (atomic_read(&q->pending_count)) { - int p = atomic_xchg(&q->pending_count, 0); - if (p) { -#ifdef XIVE_RUNTIME_CHECKS - WARN_ON(p > atomic_read(&q->count)); -#endif - atomic_sub(p, &q->count); - } - } - } - - /* - * If the most favoured prio we found pending is less - * favored (or equal) than a pending IPI, we return - * the IPI instead. - */ - if (prio >= xc->mfrr && xc->mfrr < xc->cppr) { - prio = xc->mfrr; - hirq = XICS_IPI; - break; - } - - /* If fetching, update queue pointers */ - if (scan_type == scan_fetch) { - q->idx = idx; - q->toggle = toggle; - } - } - - /* If we are just taking a "peek", do nothing else */ - if (scan_type == scan_poll) - return hirq; - - /* Update the pending bits */ - xc->pending = pending; - - /* - * If this is an EOI that's it, no CPPR adjustment done here, - * all we needed was cleanup the stale pending bits and check - * if there's anything left. - */ - if (scan_type == scan_eoi) - return hirq; - - /* - * If we found an interrupt, adjust what the guest CPPR should - * be as if we had just fetched that interrupt from HW. - * - * Note: This can only make xc->cppr smaller as the previous - * loop will only exit with hirq != 0 if prio is lower than - * the current xc->cppr. Thus we don't need to re-check xc->mfrr - * for pending IPIs. - */ - if (hirq) - xc->cppr = prio; - /* - * If it was an IPI the HW CPPR might have been lowered too much - * as the HW interrupt we use for IPIs is routed to priority 0. - * - * We re-sync it here. - */ - if (xc->cppr != xc->hw_cppr) { - xc->hw_cppr = xc->cppr; - __x_writeb(xc->cppr, __x_tima + TM_QW1_OS + TM_CPPR); - } - - return hirq; -} - -X_STATIC unsigned long GLUE(X_PFX,h_xirr)(struct kvm_vcpu *vcpu) -{ - struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; - u8 old_cppr; - u32 hirq; - - pr_devel("H_XIRR\n"); - - xc->GLUE(X_STAT_PFX,h_xirr)++; - - /* First collect pending bits from HW */ - GLUE(X_PFX,ack_pending)(xc); - - pr_devel(" new pending=0x%02x hw_cppr=%d cppr=%d\n", - xc->pending, xc->hw_cppr, xc->cppr); - - /* Grab previous CPPR and reverse map it */ - old_cppr = xive_prio_to_guest(xc->cppr); - - /* Scan for actual interrupts */ - hirq = GLUE(X_PFX,scan_interrupts)(xc, xc->pending, scan_fetch); - - pr_devel(" got hirq=0x%x hw_cppr=%d cppr=%d\n", - hirq, xc->hw_cppr, xc->cppr); - -#ifdef XIVE_RUNTIME_CHECKS - /* That should never hit */ - if (hirq & 0xff000000) - pr_warn("XIVE: Weird guest interrupt number 0x%08x\n", hirq); -#endif - - /* - * XXX We could check if the interrupt is masked here and - * filter it. If we chose to do so, we would need to do: - * - * if (masked) { - * lock(); - * if (masked) { - * old_Q = true; - * hirq = 0; - * } - * unlock(); - * } - */ - - /* Return interrupt and old CPPR in GPR4 */ - vcpu->arch.regs.gpr[4] = hirq | (old_cppr << 24); - - return H_SUCCESS; -} - -X_STATIC unsigned long GLUE(X_PFX,h_ipoll)(struct kvm_vcpu *vcpu, unsigned long server) -{ - struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; - u8 pending = xc->pending; - u32 hirq; - - pr_devel("H_IPOLL(server=%ld)\n", server); - - xc->GLUE(X_STAT_PFX,h_ipoll)++; - - /* Grab the target VCPU if not the current one */ - if (xc->server_num != server) { - vcpu = kvmppc_xive_find_server(vcpu->kvm, server); - if (!vcpu) - return H_PARAMETER; - xc = vcpu->arch.xive_vcpu; - - /* Scan all priorities */ - pending = 0xff; - } else { - /* Grab pending interrupt if any */ - __be64 qw1 = __x_readq(__x_tima + TM_QW1_OS); - u8 pipr = be64_to_cpu(qw1) & 0xff; - if (pipr < 8) - pending |= 1 << pipr; - } - - hirq = GLUE(X_PFX,scan_interrupts)(xc, pending, scan_poll); - - /* Return interrupt and old CPPR in GPR4 */ - vcpu->arch.regs.gpr[4] = hirq | (xc->cppr << 24); - - return H_SUCCESS; -} - -static void GLUE(X_PFX,push_pending_to_hw)(struct kvmppc_xive_vcpu *xc) -{ - u8 pending, prio; - - pending = xc->pending; - if (xc->mfrr != 0xff) { - if (xc->mfrr < 8) - pending |= 1 << xc->mfrr; - else - pending |= 0x80; - } - if (!pending) - return; - prio = ffs(pending) - 1; - - __x_writeb(prio, __x_tima + TM_SPC_SET_OS_PENDING); -} - -static void GLUE(X_PFX,scan_for_rerouted_irqs)(struct kvmppc_xive *xive, - struct kvmppc_xive_vcpu *xc) -{ - unsigned int prio; - - /* For each priority that is now masked */ - for (prio = xc->cppr; prio < KVMPPC_XIVE_Q_COUNT; prio++) { - struct xive_q *q = &xc->queues[prio]; - struct kvmppc_xive_irq_state *state; - struct kvmppc_xive_src_block *sb; - u32 idx, toggle, entry, irq, hw_num; - struct xive_irq_data *xd; - __be32 *qpage; - u16 src; - - idx = q->idx; - toggle = q->toggle; - qpage = READ_ONCE(q->qpage); - if (!qpage) - continue; - - /* For each interrupt in the queue */ - for (;;) { - entry = be32_to_cpup(qpage + idx); - - /* No more ? */ - if ((entry >> 31) == toggle) - break; - irq = entry & 0x7fffffff; - - /* Skip dummies and IPIs */ - if (irq == XICS_DUMMY || irq == XICS_IPI) - goto next; - sb = kvmppc_xive_find_source(xive, irq, &src); - if (!sb) - goto next; - state = &sb->irq_state[src]; - - /* Has it been rerouted ? */ - if (xc->server_num == state->act_server) - goto next; - - /* - * Allright, it *has* been re-routed, kill it from - * the queue. - */ - qpage[idx] = cpu_to_be32((entry & 0x80000000) | XICS_DUMMY); - - /* Find the HW interrupt */ - kvmppc_xive_select_irq(state, &hw_num, &xd); - - /* If it's not an LSI, set PQ to 11 the EOI will force a resend */ - if (!(xd->flags & XIVE_IRQ_FLAG_LSI)) - GLUE(X_PFX,esb_load)(xd, XIVE_ESB_SET_PQ_11); - - /* EOI the source */ - GLUE(X_PFX,source_eoi)(hw_num, xd); - - next: - idx = (idx + 1) & q->msk; - if (idx == 0) - toggle ^= 1; - } - } -} - -X_STATIC int GLUE(X_PFX,h_cppr)(struct kvm_vcpu *vcpu, unsigned long cppr) -{ - struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; - struct kvmppc_xive *xive = vcpu->kvm->arch.xive; - u8 old_cppr; - - pr_devel("H_CPPR(cppr=%ld)\n", cppr); - - xc->GLUE(X_STAT_PFX,h_cppr)++; - - /* Map CPPR */ - cppr = xive_prio_from_guest(cppr); - - /* Remember old and update SW state */ - old_cppr = xc->cppr; - xc->cppr = cppr; - - /* - * Order the above update of xc->cppr with the subsequent - * read of xc->mfrr inside push_pending_to_hw() - */ - smp_mb(); - - if (cppr > old_cppr) { - /* - * We are masking less, we need to look for pending things - * to deliver and set VP pending bits accordingly to trigger - * a new interrupt otherwise we might miss MFRR changes for - * which we have optimized out sending an IPI signal. - */ - GLUE(X_PFX,push_pending_to_hw)(xc); - } else { - /* - * We are masking more, we need to check the queue for any - * interrupt that has been routed to another CPU, take - * it out (replace it with the dummy) and retrigger it. - * - * This is necessary since those interrupts may otherwise - * never be processed, at least not until this CPU restores - * its CPPR. - * - * This is in theory racy vs. HW adding new interrupts to - * the queue. In practice this works because the interesting - * cases are when the guest has done a set_xive() to move the - * interrupt away, which flushes the xive, followed by the - * target CPU doing a H_CPPR. So any new interrupt coming into - * the queue must still be routed to us and isn't a source - * of concern. - */ - GLUE(X_PFX,scan_for_rerouted_irqs)(xive, xc); - } - - /* Apply new CPPR */ - xc->hw_cppr = cppr; - __x_writeb(cppr, __x_tima + TM_QW1_OS + TM_CPPR); - - return H_SUCCESS; -} - -X_STATIC int GLUE(X_PFX,h_eoi)(struct kvm_vcpu *vcpu, unsigned long xirr) -{ - struct kvmppc_xive *xive = vcpu->kvm->arch.xive; - struct kvmppc_xive_src_block *sb; - struct kvmppc_xive_irq_state *state; - struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; - struct xive_irq_data *xd; - u8 new_cppr = xirr >> 24; - u32 irq = xirr & 0x00ffffff, hw_num; - u16 src; - int rc = 0; - - pr_devel("H_EOI(xirr=%08lx)\n", xirr); - - xc->GLUE(X_STAT_PFX,h_eoi)++; - - xc->cppr = xive_prio_from_guest(new_cppr); - - /* - * IPIs are synthetized from MFRR and thus don't need - * any special EOI handling. The underlying interrupt - * used to signal MFRR changes is EOId when fetched from - * the queue. - */ - if (irq == XICS_IPI || irq == 0) { - /* - * This barrier orders the setting of xc->cppr vs. - * subsquent test of xc->mfrr done inside - * scan_interrupts and push_pending_to_hw - */ - smp_mb(); - goto bail; - } - - /* Find interrupt source */ - sb = kvmppc_xive_find_source(xive, irq, &src); - if (!sb) { - pr_devel(" source not found !\n"); - rc = H_PARAMETER; - /* Same as above */ - smp_mb(); - goto bail; - } - state = &sb->irq_state[src]; - kvmppc_xive_select_irq(state, &hw_num, &xd); - - state->in_eoi = true; - - /* - * This barrier orders both setting of in_eoi above vs, - * subsequent test of guest_priority, and the setting - * of xc->cppr vs. subsquent test of xc->mfrr done inside - * scan_interrupts and push_pending_to_hw - */ - smp_mb(); - -again: - if (state->guest_priority == MASKED) { - arch_spin_lock(&sb->lock); - if (state->guest_priority != MASKED) { - arch_spin_unlock(&sb->lock); - goto again; - } - pr_devel(" EOI on saved P...\n"); - - /* Clear old_p, that will cause unmask to perform an EOI */ - state->old_p = false; - - arch_spin_unlock(&sb->lock); - } else { - pr_devel(" EOI on source...\n"); - - /* Perform EOI on the source */ - GLUE(X_PFX,source_eoi)(hw_num, xd); - - /* If it's an emulated LSI, check level and resend */ - if (state->lsi && state->asserted) - __x_writeq(0, __x_trig_page(xd)); - - } - - /* - * This barrier orders the above guest_priority check - * and spin_lock/unlock with clearing in_eoi below. - * - * It also has to be a full mb() as it must ensure - * the MMIOs done in source_eoi() are completed before - * state->in_eoi is visible. - */ - mb(); - state->in_eoi = false; -bail: - - /* Re-evaluate pending IRQs and update HW */ - GLUE(X_PFX,scan_interrupts)(xc, xc->pending, scan_eoi); - GLUE(X_PFX,push_pending_to_hw)(xc); - pr_devel(" after scan pending=%02x\n", xc->pending); - - /* Apply new CPPR */ - xc->hw_cppr = xc->cppr; - __x_writeb(xc->cppr, __x_tima + TM_QW1_OS + TM_CPPR); - - return rc; -} - -X_STATIC int GLUE(X_PFX,h_ipi)(struct kvm_vcpu *vcpu, unsigned long server, - unsigned long mfrr) -{ - struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; - - pr_devel("H_IPI(server=%08lx,mfrr=%ld)\n", server, mfrr); - - xc->GLUE(X_STAT_PFX,h_ipi)++; - - /* Find target */ - vcpu = kvmppc_xive_find_server(vcpu->kvm, server); - if (!vcpu) - return H_PARAMETER; - xc = vcpu->arch.xive_vcpu; - - /* Locklessly write over MFRR */ - xc->mfrr = mfrr; - - /* - * The load of xc->cppr below and the subsequent MMIO store - * to the IPI must happen after the above mfrr update is - * globally visible so that: - * - * - Synchronize with another CPU doing an H_EOI or a H_CPPR - * updating xc->cppr then reading xc->mfrr. - * - * - The target of the IPI sees the xc->mfrr update - */ - mb(); - - /* Shoot the IPI if most favored than target cppr */ - if (mfrr < xc->cppr) - __x_writeq(0, __x_trig_page(&xc->vp_ipi_data)); - - return H_SUCCESS; -} |