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author | Michael Ellerman <mpe@ellerman.id.au> | 2019-08-19 13:19:43 +1000 |
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committer | Michael Ellerman <mpe@ellerman.id.au> | 2019-08-19 13:19:43 +1000 |
commit | 1a47908e0f81803115d679271a64d84351c91870 (patch) | |
tree | 26f23189be6a11ea245f5ce033511e6801d67739 /arch/powerpc/sysdev | |
parent | 4215fa2d7d3a872c4f6f383dc52961215b0ce2d6 (diff) | |
parent | da15c03b047dca891d37b9f4ef9ca14d84a6484f (diff) | |
download | linux-1a47908e0f81803115d679271a64d84351c91870.tar.gz linux-1a47908e0f81803115d679271a64d84351c91870.tar.bz2 linux-1a47908e0f81803115d679271a64d84351c91870.zip |
Merge branch 'topic/ppc-kvm' into next
Merge our ppc-kvm topic branch. This contains several fixes for the XIVE
interrupt controller that we are sharing with the KVM tree.
Diffstat (limited to 'arch/powerpc/sysdev')
-rw-r--r-- | arch/powerpc/sysdev/xive/common.c | 87 |
1 files changed, 64 insertions, 23 deletions
diff --git a/arch/powerpc/sysdev/xive/common.c b/arch/powerpc/sysdev/xive/common.c index 083f657091d7..6b973b7cdd8a 100644 --- a/arch/powerpc/sysdev/xive/common.c +++ b/arch/powerpc/sysdev/xive/common.c @@ -135,7 +135,7 @@ static u32 xive_read_eq(struct xive_q *q, bool just_peek) static u32 xive_scan_interrupts(struct xive_cpu *xc, bool just_peek) { u32 irq = 0; - u8 prio; + u8 prio = 0; /* Find highest pending priority */ while (xc->pending_prio != 0) { @@ -148,8 +148,19 @@ static u32 xive_scan_interrupts(struct xive_cpu *xc, bool just_peek) irq = xive_read_eq(&xc->queue[prio], just_peek); /* Found something ? That's it */ - if (irq) - break; + if (irq) { + if (just_peek || irq_to_desc(irq)) + break; + /* + * We should never get here; if we do then we must + * have failed to synchronize the interrupt properly + * when shutting it down. + */ + pr_crit("xive: got interrupt %d without descriptor, dropping\n", + irq); + WARN_ON(1); + continue; + } /* Clear pending bits */ xc->pending_prio &= ~(1 << prio); @@ -307,6 +318,7 @@ static void xive_do_queue_eoi(struct xive_cpu *xc) */ static void xive_do_source_eoi(u32 hw_irq, struct xive_irq_data *xd) { + xd->stale_p = false; /* If the XIVE supports the new "store EOI facility, use it */ if (xd->flags & XIVE_IRQ_FLAG_STORE_EOI) xive_esb_write(xd, XIVE_ESB_STORE_EOI, 0); @@ -350,7 +362,7 @@ static void xive_do_source_eoi(u32 hw_irq, struct xive_irq_data *xd) } } -/* irq_chip eoi callback */ +/* irq_chip eoi callback, called with irq descriptor lock held */ static void xive_irq_eoi(struct irq_data *d) { struct xive_irq_data *xd = irq_data_get_irq_handler_data(d); @@ -366,6 +378,8 @@ static void xive_irq_eoi(struct irq_data *d) if (!irqd_irq_disabled(d) && !irqd_is_forwarded_to_vcpu(d) && !(xd->flags & XIVE_IRQ_NO_EOI)) xive_do_source_eoi(irqd_to_hwirq(d), xd); + else + xd->stale_p = true; /* * Clear saved_p to indicate that it's no longer occupying @@ -397,11 +411,16 @@ static void xive_do_source_set_mask(struct xive_irq_data *xd, */ if (mask) { val = xive_esb_read(xd, XIVE_ESB_SET_PQ_01); - xd->saved_p = !!(val & XIVE_ESB_VAL_P); - } else if (xd->saved_p) + if (!xd->stale_p && !!(val & XIVE_ESB_VAL_P)) + xd->saved_p = true; + xd->stale_p = false; + } else if (xd->saved_p) { xive_esb_read(xd, XIVE_ESB_SET_PQ_10); - else + xd->saved_p = false; + } else { xive_esb_read(xd, XIVE_ESB_SET_PQ_00); + xd->stale_p = false; + } } /* @@ -541,6 +560,8 @@ static unsigned int xive_irq_startup(struct irq_data *d) unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d); int target, rc; + xd->saved_p = false; + xd->stale_p = false; pr_devel("xive_irq_startup: irq %d [0x%x] data @%p\n", d->irq, hw_irq, d); @@ -587,6 +608,7 @@ static unsigned int xive_irq_startup(struct irq_data *d) return 0; } +/* called with irq descriptor lock held */ static void xive_irq_shutdown(struct irq_data *d) { struct xive_irq_data *xd = irq_data_get_irq_handler_data(d); @@ -602,16 +624,6 @@ static void xive_irq_shutdown(struct irq_data *d) xive_do_source_set_mask(xd, true); /* - * The above may have set saved_p. We clear it otherwise it - * will prevent re-enabling later on. It is ok to forget the - * fact that the interrupt might be in a queue because we are - * accounting that already in xive_dec_target_count() and will - * be re-routing it to a new queue with proper accounting when - * it's started up again - */ - xd->saved_p = false; - - /* * Mask the interrupt in HW in the IVT/EAS and set the number * to be the "bad" IRQ number */ @@ -797,6 +809,10 @@ static int xive_irq_retrigger(struct irq_data *d) return 1; } +/* + * Caller holds the irq descriptor lock, so this won't be called + * concurrently with xive_get_irqchip_state on the same interrupt. + */ static int xive_irq_set_vcpu_affinity(struct irq_data *d, void *state) { struct xive_irq_data *xd = irq_data_get_irq_handler_data(d); @@ -820,6 +836,10 @@ static int xive_irq_set_vcpu_affinity(struct irq_data *d, void *state) /* Set it to PQ=10 state to prevent further sends */ pq = xive_esb_read(xd, XIVE_ESB_SET_PQ_10); + if (!xd->stale_p) { + xd->saved_p = !!(pq & XIVE_ESB_VAL_P); + xd->stale_p = !xd->saved_p; + } /* No target ? nothing to do */ if (xd->target == XIVE_INVALID_TARGET) { @@ -827,7 +847,7 @@ static int xive_irq_set_vcpu_affinity(struct irq_data *d, void *state) * An untargetted interrupt should have been * also masked at the source */ - WARN_ON(pq & 2); + WARN_ON(xd->saved_p); return 0; } @@ -847,9 +867,8 @@ static int xive_irq_set_vcpu_affinity(struct irq_data *d, void *state) * This saved_p is cleared by the host EOI, when we know * for sure the queue slot is no longer in use. */ - if (pq & 2) { - pq = xive_esb_read(xd, XIVE_ESB_SET_PQ_11); - xd->saved_p = true; + if (xd->saved_p) { + xive_esb_read(xd, XIVE_ESB_SET_PQ_11); /* * Sync the XIVE source HW to ensure the interrupt @@ -862,8 +881,7 @@ static int xive_irq_set_vcpu_affinity(struct irq_data *d, void *state) */ if (xive_ops->sync_source) xive_ops->sync_source(hw_irq); - } else - xd->saved_p = false; + } } else { irqd_clr_forwarded_to_vcpu(d); @@ -914,6 +932,23 @@ static int xive_irq_set_vcpu_affinity(struct irq_data *d, void *state) return 0; } +/* Called with irq descriptor lock held. */ +static int xive_get_irqchip_state(struct irq_data *data, + enum irqchip_irq_state which, bool *state) +{ + struct xive_irq_data *xd = irq_data_get_irq_handler_data(data); + + switch (which) { + case IRQCHIP_STATE_ACTIVE: + *state = !xd->stale_p && + (xd->saved_p || + !!(xive_esb_read(xd, XIVE_ESB_GET) & XIVE_ESB_VAL_P)); + return 0; + default: + return -EINVAL; + } +} + static struct irq_chip xive_irq_chip = { .name = "XIVE-IRQ", .irq_startup = xive_irq_startup, @@ -925,6 +960,7 @@ static struct irq_chip xive_irq_chip = { .irq_set_type = xive_irq_set_type, .irq_retrigger = xive_irq_retrigger, .irq_set_vcpu_affinity = xive_irq_set_vcpu_affinity, + .irq_get_irqchip_state = xive_get_irqchip_state, }; bool is_xive_irq(struct irq_chip *chip) @@ -1338,6 +1374,11 @@ static void xive_flush_cpu_queue(unsigned int cpu, struct xive_cpu *xc) xd = irq_desc_get_handler_data(desc); /* + * Clear saved_p to indicate that it's no longer pending + */ + xd->saved_p = false; + + /* * For LSIs, we EOI, this will cause a resend if it's * still asserted. Otherwise do an MSI retrigger. */ |