forked from Minki/linux
5400fc229e
Merge the topic branch we share with kvm-ppc, this brings in two xive commits, one from Paul to rework HMI handling, and a minor cleanup to drop an unused flag.
1489 lines
37 KiB
C
1489 lines
37 KiB
C
/*
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* Copyright 2016,2017 IBM Corporation.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#define pr_fmt(fmt) "xive: " fmt
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#include <linux/types.h>
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#include <linux/threads.h>
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#include <linux/kernel.h>
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#include <linux/irq.h>
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#include <linux/debugfs.h>
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#include <linux/smp.h>
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#include <linux/interrupt.h>
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#include <linux/seq_file.h>
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#include <linux/init.h>
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#include <linux/cpu.h>
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#include <linux/of.h>
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include <linux/msi.h>
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#include <asm/prom.h>
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#include <asm/io.h>
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#include <asm/smp.h>
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#include <asm/machdep.h>
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#include <asm/irq.h>
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#include <asm/errno.h>
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#include <asm/xive.h>
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#include <asm/xive-regs.h>
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#include <asm/xmon.h>
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#include "xive-internal.h"
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#undef DEBUG_FLUSH
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#undef DEBUG_ALL
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#ifdef DEBUG_ALL
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#define DBG_VERBOSE(fmt, ...) pr_devel("cpu %d - " fmt, \
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smp_processor_id(), ## __VA_ARGS__)
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#else
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#define DBG_VERBOSE(fmt...) do { } while(0)
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#endif
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bool __xive_enabled;
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EXPORT_SYMBOL_GPL(__xive_enabled);
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bool xive_cmdline_disabled;
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/* We use only one priority for now */
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static u8 xive_irq_priority;
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/* TIMA exported to KVM */
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void __iomem *xive_tima;
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EXPORT_SYMBOL_GPL(xive_tima);
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u32 xive_tima_offset;
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/* Backend ops */
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static const struct xive_ops *xive_ops;
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/* Our global interrupt domain */
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static struct irq_domain *xive_irq_domain;
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#ifdef CONFIG_SMP
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/* The IPIs all use the same logical irq number */
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static u32 xive_ipi_irq;
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#endif
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/* Xive state for each CPU */
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static DEFINE_PER_CPU(struct xive_cpu *, xive_cpu);
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/*
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* A "disabled" interrupt should never fire, to catch problems
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* we set its logical number to this
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*/
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#define XIVE_BAD_IRQ 0x7fffffff
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#define XIVE_MAX_IRQ (XIVE_BAD_IRQ - 1)
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/* An invalid CPU target */
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#define XIVE_INVALID_TARGET (-1)
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/*
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* Read the next entry in a queue, return its content if it's valid
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* or 0 if there is no new entry.
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*
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* The queue pointer is moved forward unless "just_peek" is set
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*/
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static u32 xive_read_eq(struct xive_q *q, bool just_peek)
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{
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u32 cur;
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if (!q->qpage)
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return 0;
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cur = be32_to_cpup(q->qpage + q->idx);
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/* Check valid bit (31) vs current toggle polarity */
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if ((cur >> 31) == q->toggle)
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return 0;
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/* If consuming from the queue ... */
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if (!just_peek) {
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/* Next entry */
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q->idx = (q->idx + 1) & q->msk;
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/* Wrap around: flip valid toggle */
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if (q->idx == 0)
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q->toggle ^= 1;
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}
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/* Mask out the valid bit (31) */
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return cur & 0x7fffffff;
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}
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/*
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* Scans all the queue that may have interrupts in them
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* (based on "pending_prio") in priority order until an
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* interrupt is found or all the queues are empty.
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*
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* Then updates the CPPR (Current Processor Priority
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* Register) based on the most favored interrupt found
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* (0xff if none) and return what was found (0 if none).
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*
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* If just_peek is set, return the most favored pending
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* interrupt if any but don't update the queue pointers.
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*
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* Note: This function can operate generically on any number
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* of queues (up to 8). The current implementation of the XIVE
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* driver only uses a single queue however.
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*
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* Note2: This will also "flush" "the pending_count" of a queue
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* into the "count" when that queue is observed to be empty.
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* This is used to keep track of the amount of interrupts
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* targetting a queue. When an interrupt is moved away from
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* a queue, we only decrement that queue count once the queue
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* has been observed empty to avoid races.
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*/
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static u32 xive_scan_interrupts(struct xive_cpu *xc, bool just_peek)
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{
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u32 irq = 0;
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u8 prio;
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/* Find highest pending priority */
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while (xc->pending_prio != 0) {
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struct xive_q *q;
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prio = ffs(xc->pending_prio) - 1;
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DBG_VERBOSE("scan_irq: trying prio %d\n", prio);
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/* Try to fetch */
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irq = xive_read_eq(&xc->queue[prio], just_peek);
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/* Found something ? That's it */
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if (irq)
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break;
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/* Clear pending bits */
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xc->pending_prio &= ~(1 << prio);
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/*
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* Check if the queue count needs adjusting due to
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* interrupts being moved away. See description of
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* xive_dec_target_count()
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*/
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q = &xc->queue[prio];
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if (atomic_read(&q->pending_count)) {
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int p = atomic_xchg(&q->pending_count, 0);
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if (p) {
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WARN_ON(p > atomic_read(&q->count));
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atomic_sub(p, &q->count);
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}
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}
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}
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/* If nothing was found, set CPPR to 0xff */
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if (irq == 0)
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prio = 0xff;
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/* Update HW CPPR to match if necessary */
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if (prio != xc->cppr) {
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DBG_VERBOSE("scan_irq: adjusting CPPR to %d\n", prio);
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xc->cppr = prio;
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out_8(xive_tima + xive_tima_offset + TM_CPPR, prio);
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}
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return irq;
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}
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/*
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* This is used to perform the magic loads from an ESB
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* described in xive.h
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*/
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static notrace u8 xive_esb_read(struct xive_irq_data *xd, u32 offset)
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{
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u64 val;
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/* Handle HW errata */
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if (xd->flags & XIVE_IRQ_FLAG_SHIFT_BUG)
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offset |= offset << 4;
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if ((xd->flags & XIVE_IRQ_FLAG_H_INT_ESB) && xive_ops->esb_rw)
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val = xive_ops->esb_rw(xd->hw_irq, offset, 0, 0);
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else
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val = in_be64(xd->eoi_mmio + offset);
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return (u8)val;
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}
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static void xive_esb_write(struct xive_irq_data *xd, u32 offset, u64 data)
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{
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/* Handle HW errata */
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if (xd->flags & XIVE_IRQ_FLAG_SHIFT_BUG)
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offset |= offset << 4;
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if ((xd->flags & XIVE_IRQ_FLAG_H_INT_ESB) && xive_ops->esb_rw)
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xive_ops->esb_rw(xd->hw_irq, offset, data, 1);
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else
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out_be64(xd->eoi_mmio + offset, data);
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}
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#ifdef CONFIG_XMON
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static notrace void xive_dump_eq(const char *name, struct xive_q *q)
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{
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u32 i0, i1, idx;
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if (!q->qpage)
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return;
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idx = q->idx;
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i0 = be32_to_cpup(q->qpage + idx);
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idx = (idx + 1) & q->msk;
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i1 = be32_to_cpup(q->qpage + idx);
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xmon_printf(" %s Q T=%d %08x %08x ...\n", name,
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q->toggle, i0, i1);
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}
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notrace void xmon_xive_do_dump(int cpu)
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{
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struct xive_cpu *xc = per_cpu(xive_cpu, cpu);
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xmon_printf("XIVE state for CPU %d:\n", cpu);
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xmon_printf(" pp=%02x cppr=%02x\n", xc->pending_prio, xc->cppr);
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xive_dump_eq("IRQ", &xc->queue[xive_irq_priority]);
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#ifdef CONFIG_SMP
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{
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u64 val = xive_esb_read(&xc->ipi_data, XIVE_ESB_GET);
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xmon_printf(" IPI state: %x:%c%c\n", xc->hw_ipi,
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val & XIVE_ESB_VAL_P ? 'P' : 'p',
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val & XIVE_ESB_VAL_P ? 'Q' : 'q');
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}
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#endif
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}
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#endif /* CONFIG_XMON */
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static unsigned int xive_get_irq(void)
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{
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struct xive_cpu *xc = __this_cpu_read(xive_cpu);
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u32 irq;
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/*
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* This can be called either as a result of a HW interrupt or
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* as a "replay" because EOI decided there was still something
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* in one of the queues.
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*
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* First we perform an ACK cycle in order to update our mask
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* of pending priorities. This will also have the effect of
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* updating the CPPR to the most favored pending interrupts.
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*
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* In the future, if we have a way to differenciate a first
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* entry (on HW interrupt) from a replay triggered by EOI,
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* we could skip this on replays unless we soft-mask tells us
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* that a new HW interrupt occurred.
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*/
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xive_ops->update_pending(xc);
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DBG_VERBOSE("get_irq: pending=%02x\n", xc->pending_prio);
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/* Scan our queue(s) for interrupts */
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irq = xive_scan_interrupts(xc, false);
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DBG_VERBOSE("get_irq: got irq 0x%x, new pending=0x%02x\n",
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irq, xc->pending_prio);
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/* Return pending interrupt if any */
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if (irq == XIVE_BAD_IRQ)
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return 0;
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return irq;
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}
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/*
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* After EOI'ing an interrupt, we need to re-check the queue
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* to see if another interrupt is pending since multiple
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* interrupts can coalesce into a single notification to the
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* CPU.
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*
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* If we find that there is indeed more in there, we call
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* force_external_irq_replay() to make Linux synthetize an
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* external interrupt on the next call to local_irq_restore().
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*/
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static void xive_do_queue_eoi(struct xive_cpu *xc)
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{
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if (xive_scan_interrupts(xc, true) != 0) {
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DBG_VERBOSE("eoi: pending=0x%02x\n", xc->pending_prio);
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force_external_irq_replay();
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}
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}
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/*
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* EOI an interrupt at the source. There are several methods
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* to do this depending on the HW version and source type
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*/
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void xive_do_source_eoi(u32 hw_irq, struct xive_irq_data *xd)
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{
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/* If the XIVE supports the new "store EOI facility, use it */
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if (xd->flags & XIVE_IRQ_FLAG_STORE_EOI)
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xive_esb_write(xd, XIVE_ESB_STORE_EOI, 0);
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else if (hw_irq && xd->flags & XIVE_IRQ_FLAG_EOI_FW) {
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/*
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* The FW told us to call it. This happens for some
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* interrupt sources that need additional HW whacking
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* beyond the ESB manipulation. For example LPC interrupts
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* on P9 DD1.0 need a latch to be clared in the LPC bridge
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* itself. The Firmware will take care of it.
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*/
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if (WARN_ON_ONCE(!xive_ops->eoi))
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return;
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xive_ops->eoi(hw_irq);
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} else {
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u8 eoi_val;
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/*
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* Otherwise for EOI, we use the special MMIO that does
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* a clear of both P and Q and returns the old Q,
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* except for LSIs where we use the "EOI cycle" special
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* load.
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*
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* This allows us to then do a re-trigger if Q was set
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* rather than synthesizing an interrupt in software
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*
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* For LSIs, using the HW EOI cycle works around a problem
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* on P9 DD1 PHBs where the other ESB accesses don't work
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* properly.
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*/
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if (xd->flags & XIVE_IRQ_FLAG_LSI)
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xive_esb_read(xd, XIVE_ESB_LOAD_EOI);
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else {
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eoi_val = xive_esb_read(xd, XIVE_ESB_SET_PQ_00);
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DBG_VERBOSE("eoi_val=%x\n", eoi_val);
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/* Re-trigger if needed */
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if ((eoi_val & XIVE_ESB_VAL_Q) && xd->trig_mmio)
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out_be64(xd->trig_mmio, 0);
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}
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}
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}
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/* irq_chip eoi callback */
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static void xive_irq_eoi(struct irq_data *d)
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{
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struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
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struct xive_cpu *xc = __this_cpu_read(xive_cpu);
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DBG_VERBOSE("eoi_irq: irq=%d [0x%lx] pending=%02x\n",
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d->irq, irqd_to_hwirq(d), xc->pending_prio);
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/*
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* EOI the source if it hasn't been disabled and hasn't
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* been passed-through to a KVM guest
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*/
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if (!irqd_irq_disabled(d) && !irqd_is_forwarded_to_vcpu(d) &&
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!(xd->flags & XIVE_IRQ_NO_EOI))
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xive_do_source_eoi(irqd_to_hwirq(d), xd);
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/*
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* Clear saved_p to indicate that it's no longer occupying
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* a queue slot on the target queue
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*/
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xd->saved_p = false;
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/* Check for more work in the queue */
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xive_do_queue_eoi(xc);
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}
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/*
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* Helper used to mask and unmask an interrupt source. This
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* is only called for normal interrupts that do not require
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* masking/unmasking via firmware.
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*/
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static void xive_do_source_set_mask(struct xive_irq_data *xd,
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bool mask)
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{
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u64 val;
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/*
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* If the interrupt had P set, it may be in a queue.
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*
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* We need to make sure we don't re-enable it until it
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* has been fetched from that queue and EOId. We keep
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* a copy of that P state and use it to restore the
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* ESB accordingly on unmask.
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*/
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if (mask) {
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val = xive_esb_read(xd, XIVE_ESB_SET_PQ_01);
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xd->saved_p = !!(val & XIVE_ESB_VAL_P);
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} else if (xd->saved_p)
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xive_esb_read(xd, XIVE_ESB_SET_PQ_10);
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else
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xive_esb_read(xd, XIVE_ESB_SET_PQ_00);
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}
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/*
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* Try to chose "cpu" as a new interrupt target. Increments
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* the queue accounting for that target if it's not already
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* full.
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*/
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static bool xive_try_pick_target(int cpu)
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{
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struct xive_cpu *xc = per_cpu(xive_cpu, cpu);
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struct xive_q *q = &xc->queue[xive_irq_priority];
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int max;
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/*
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* Calculate max number of interrupts in that queue.
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*
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* We leave a gap of 1 just in case...
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*/
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max = (q->msk + 1) - 1;
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return !!atomic_add_unless(&q->count, 1, max);
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}
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/*
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* Un-account an interrupt for a target CPU. We don't directly
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* decrement q->count since the interrupt might still be present
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* in the queue.
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*
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* Instead increment a separate counter "pending_count" which
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* will be substracted from "count" later when that CPU observes
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* the queue to be empty.
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*/
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static void xive_dec_target_count(int cpu)
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{
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struct xive_cpu *xc = per_cpu(xive_cpu, cpu);
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struct xive_q *q = &xc->queue[xive_irq_priority];
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if (unlikely(WARN_ON(cpu < 0 || !xc))) {
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pr_err("%s: cpu=%d xc=%p\n", __func__, cpu, xc);
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return;
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}
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/*
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* We increment the "pending count" which will be used
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* to decrement the target queue count whenever it's next
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* processed and found empty. This ensure that we don't
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* decrement while we still have the interrupt there
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* occupying a slot.
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*/
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atomic_inc(&q->pending_count);
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}
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/* Find a tentative CPU target in a CPU mask */
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static int xive_find_target_in_mask(const struct cpumask *mask,
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unsigned int fuzz)
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{
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int cpu, first, num, i;
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/* Pick up a starting point CPU in the mask based on fuzz */
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num = min_t(int, cpumask_weight(mask), nr_cpu_ids);
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first = fuzz % num;
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/* Locate it */
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cpu = cpumask_first(mask);
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for (i = 0; i < first && cpu < nr_cpu_ids; i++)
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cpu = cpumask_next(cpu, mask);
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/* Sanity check */
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if (WARN_ON(cpu >= nr_cpu_ids))
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cpu = cpumask_first(cpu_online_mask);
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/* Remember first one to handle wrap-around */
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first = cpu;
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/*
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* Now go through the entire mask until we find a valid
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* target.
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*/
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for (;;) {
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/*
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* We re-check online as the fallback case passes us
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* an untested affinity mask
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*/
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if (cpu_online(cpu) && xive_try_pick_target(cpu))
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return cpu;
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cpu = cpumask_next(cpu, mask);
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if (cpu == first)
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break;
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/* Wrap around */
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if (cpu >= nr_cpu_ids)
|
|
cpu = cpumask_first(mask);
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Pick a target CPU for an interrupt. This is done at
|
|
* startup or if the affinity is changed in a way that
|
|
* invalidates the current target.
|
|
*/
|
|
static int xive_pick_irq_target(struct irq_data *d,
|
|
const struct cpumask *affinity)
|
|
{
|
|
static unsigned int fuzz;
|
|
struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
|
|
cpumask_var_t mask;
|
|
int cpu = -1;
|
|
|
|
/*
|
|
* If we have chip IDs, first we try to build a mask of
|
|
* CPUs matching the CPU and find a target in there
|
|
*/
|
|
if (xd->src_chip != XIVE_INVALID_CHIP_ID &&
|
|
zalloc_cpumask_var(&mask, GFP_ATOMIC)) {
|
|
/* Build a mask of matching chip IDs */
|
|
for_each_cpu_and(cpu, affinity, cpu_online_mask) {
|
|
struct xive_cpu *xc = per_cpu(xive_cpu, cpu);
|
|
if (xc->chip_id == xd->src_chip)
|
|
cpumask_set_cpu(cpu, mask);
|
|
}
|
|
/* Try to find a target */
|
|
if (cpumask_empty(mask))
|
|
cpu = -1;
|
|
else
|
|
cpu = xive_find_target_in_mask(mask, fuzz++);
|
|
free_cpumask_var(mask);
|
|
if (cpu >= 0)
|
|
return cpu;
|
|
fuzz--;
|
|
}
|
|
|
|
/* No chip IDs, fallback to using the affinity mask */
|
|
return xive_find_target_in_mask(affinity, fuzz++);
|
|
}
|
|
|
|
static unsigned int xive_irq_startup(struct irq_data *d)
|
|
{
|
|
struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
|
|
unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
|
|
int target, rc;
|
|
|
|
pr_devel("xive_irq_startup: irq %d [0x%x] data @%p\n",
|
|
d->irq, hw_irq, d);
|
|
|
|
#ifdef CONFIG_PCI_MSI
|
|
/*
|
|
* The generic MSI code returns with the interrupt disabled on the
|
|
* card, using the MSI mask bits. Firmware doesn't appear to unmask
|
|
* at that level, so we do it here by hand.
|
|
*/
|
|
if (irq_data_get_msi_desc(d))
|
|
pci_msi_unmask_irq(d);
|
|
#endif
|
|
|
|
/* Pick a target */
|
|
target = xive_pick_irq_target(d, irq_data_get_affinity_mask(d));
|
|
if (target == XIVE_INVALID_TARGET) {
|
|
/* Try again breaking affinity */
|
|
target = xive_pick_irq_target(d, cpu_online_mask);
|
|
if (target == XIVE_INVALID_TARGET)
|
|
return -ENXIO;
|
|
pr_warn("irq %d started with broken affinity\n", d->irq);
|
|
}
|
|
|
|
/* Sanity check */
|
|
if (WARN_ON(target == XIVE_INVALID_TARGET ||
|
|
target >= nr_cpu_ids))
|
|
target = smp_processor_id();
|
|
|
|
xd->target = target;
|
|
|
|
/*
|
|
* Configure the logical number to be the Linux IRQ number
|
|
* and set the target queue
|
|
*/
|
|
rc = xive_ops->configure_irq(hw_irq,
|
|
get_hard_smp_processor_id(target),
|
|
xive_irq_priority, d->irq);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* Unmask the ESB */
|
|
xive_do_source_set_mask(xd, false);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void xive_irq_shutdown(struct irq_data *d)
|
|
{
|
|
struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
|
|
unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
|
|
|
|
pr_devel("xive_irq_shutdown: irq %d [0x%x] data @%p\n",
|
|
d->irq, hw_irq, d);
|
|
|
|
if (WARN_ON(xd->target == XIVE_INVALID_TARGET))
|
|
return;
|
|
|
|
/* Mask the interrupt at the source */
|
|
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
|
|
*/
|
|
xive_ops->configure_irq(hw_irq,
|
|
get_hard_smp_processor_id(xd->target),
|
|
0xff, XIVE_BAD_IRQ);
|
|
|
|
xive_dec_target_count(xd->target);
|
|
xd->target = XIVE_INVALID_TARGET;
|
|
}
|
|
|
|
static void xive_irq_unmask(struct irq_data *d)
|
|
{
|
|
struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
|
|
|
|
pr_devel("xive_irq_unmask: irq %d data @%p\n", d->irq, xd);
|
|
|
|
/*
|
|
* This is a workaround for PCI LSI problems on P9, for
|
|
* these, we call FW to set the mask. The problems might
|
|
* be fixed by P9 DD2.0, if that is the case, firmware
|
|
* will no longer set that flag.
|
|
*/
|
|
if (xd->flags & XIVE_IRQ_FLAG_MASK_FW) {
|
|
unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
|
|
xive_ops->configure_irq(hw_irq,
|
|
get_hard_smp_processor_id(xd->target),
|
|
xive_irq_priority, d->irq);
|
|
return;
|
|
}
|
|
|
|
xive_do_source_set_mask(xd, false);
|
|
}
|
|
|
|
static void xive_irq_mask(struct irq_data *d)
|
|
{
|
|
struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
|
|
|
|
pr_devel("xive_irq_mask: irq %d data @%p\n", d->irq, xd);
|
|
|
|
/*
|
|
* This is a workaround for PCI LSI problems on P9, for
|
|
* these, we call OPAL to set the mask. The problems might
|
|
* be fixed by P9 DD2.0, if that is the case, firmware
|
|
* will no longer set that flag.
|
|
*/
|
|
if (xd->flags & XIVE_IRQ_FLAG_MASK_FW) {
|
|
unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
|
|
xive_ops->configure_irq(hw_irq,
|
|
get_hard_smp_processor_id(xd->target),
|
|
0xff, d->irq);
|
|
return;
|
|
}
|
|
|
|
xive_do_source_set_mask(xd, true);
|
|
}
|
|
|
|
static int xive_irq_set_affinity(struct irq_data *d,
|
|
const struct cpumask *cpumask,
|
|
bool force)
|
|
{
|
|
struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
|
|
unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
|
|
u32 target, old_target;
|
|
int rc = 0;
|
|
|
|
pr_devel("xive_irq_set_affinity: irq %d\n", d->irq);
|
|
|
|
/* Is this valid ? */
|
|
if (cpumask_any_and(cpumask, cpu_online_mask) >= nr_cpu_ids)
|
|
return -EINVAL;
|
|
|
|
/* Don't do anything if the interrupt isn't started */
|
|
if (!irqd_is_started(d))
|
|
return IRQ_SET_MASK_OK;
|
|
|
|
/*
|
|
* If existing target is already in the new mask, and is
|
|
* online then do nothing.
|
|
*/
|
|
if (xd->target != XIVE_INVALID_TARGET &&
|
|
cpu_online(xd->target) &&
|
|
cpumask_test_cpu(xd->target, cpumask))
|
|
return IRQ_SET_MASK_OK;
|
|
|
|
/* Pick a new target */
|
|
target = xive_pick_irq_target(d, cpumask);
|
|
|
|
/* No target found */
|
|
if (target == XIVE_INVALID_TARGET)
|
|
return -ENXIO;
|
|
|
|
/* Sanity check */
|
|
if (WARN_ON(target >= nr_cpu_ids))
|
|
target = smp_processor_id();
|
|
|
|
old_target = xd->target;
|
|
|
|
/*
|
|
* Only configure the irq if it's not currently passed-through to
|
|
* a KVM guest
|
|
*/
|
|
if (!irqd_is_forwarded_to_vcpu(d))
|
|
rc = xive_ops->configure_irq(hw_irq,
|
|
get_hard_smp_processor_id(target),
|
|
xive_irq_priority, d->irq);
|
|
if (rc < 0) {
|
|
pr_err("Error %d reconfiguring irq %d\n", rc, d->irq);
|
|
return rc;
|
|
}
|
|
|
|
pr_devel(" target: 0x%x\n", target);
|
|
xd->target = target;
|
|
|
|
/* Give up previous target */
|
|
if (old_target != XIVE_INVALID_TARGET)
|
|
xive_dec_target_count(old_target);
|
|
|
|
return IRQ_SET_MASK_OK;
|
|
}
|
|
|
|
static int xive_irq_set_type(struct irq_data *d, unsigned int flow_type)
|
|
{
|
|
struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
|
|
|
|
/*
|
|
* We only support these. This has really no effect other than setting
|
|
* the corresponding descriptor bits mind you but those will in turn
|
|
* affect the resend function when re-enabling an edge interrupt.
|
|
*
|
|
* Set set the default to edge as explained in map().
|
|
*/
|
|
if (flow_type == IRQ_TYPE_DEFAULT || flow_type == IRQ_TYPE_NONE)
|
|
flow_type = IRQ_TYPE_EDGE_RISING;
|
|
|
|
if (flow_type != IRQ_TYPE_EDGE_RISING &&
|
|
flow_type != IRQ_TYPE_LEVEL_LOW)
|
|
return -EINVAL;
|
|
|
|
irqd_set_trigger_type(d, flow_type);
|
|
|
|
/*
|
|
* Double check it matches what the FW thinks
|
|
*
|
|
* NOTE: We don't know yet if the PAPR interface will provide
|
|
* the LSI vs MSI information apart from the device-tree so
|
|
* this check might have to move into an optional backend call
|
|
* that is specific to the native backend
|
|
*/
|
|
if ((flow_type == IRQ_TYPE_LEVEL_LOW) !=
|
|
!!(xd->flags & XIVE_IRQ_FLAG_LSI)) {
|
|
pr_warn("Interrupt %d (HW 0x%x) type mismatch, Linux says %s, FW says %s\n",
|
|
d->irq, (u32)irqd_to_hwirq(d),
|
|
(flow_type == IRQ_TYPE_LEVEL_LOW) ? "Level" : "Edge",
|
|
(xd->flags & XIVE_IRQ_FLAG_LSI) ? "Level" : "Edge");
|
|
}
|
|
|
|
return IRQ_SET_MASK_OK_NOCOPY;
|
|
}
|
|
|
|
static int xive_irq_retrigger(struct irq_data *d)
|
|
{
|
|
struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
|
|
|
|
/* This should be only for MSIs */
|
|
if (WARN_ON(xd->flags & XIVE_IRQ_FLAG_LSI))
|
|
return 0;
|
|
|
|
/*
|
|
* To perform a retrigger, we first set the PQ bits to
|
|
* 11, then perform an EOI.
|
|
*/
|
|
xive_esb_read(xd, XIVE_ESB_SET_PQ_11);
|
|
|
|
/*
|
|
* Note: We pass "0" to the hw_irq argument in order to
|
|
* avoid calling into the backend EOI code which we don't
|
|
* want to do in the case of a re-trigger. Backends typically
|
|
* only do EOI for LSIs anyway.
|
|
*/
|
|
xive_do_source_eoi(0, xd);
|
|
|
|
return 1;
|
|
}
|
|
|
|
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);
|
|
unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
|
|
int rc;
|
|
u8 pq;
|
|
|
|
/*
|
|
* We only support this on interrupts that do not require
|
|
* firmware calls for masking and unmasking
|
|
*/
|
|
if (xd->flags & XIVE_IRQ_FLAG_MASK_FW)
|
|
return -EIO;
|
|
|
|
/*
|
|
* This is called by KVM with state non-NULL for enabling
|
|
* pass-through or NULL for disabling it
|
|
*/
|
|
if (state) {
|
|
irqd_set_forwarded_to_vcpu(d);
|
|
|
|
/* Set it to PQ=10 state to prevent further sends */
|
|
pq = xive_esb_read(xd, XIVE_ESB_SET_PQ_10);
|
|
|
|
/* No target ? nothing to do */
|
|
if (xd->target == XIVE_INVALID_TARGET) {
|
|
/*
|
|
* An untargetted interrupt should have been
|
|
* also masked at the source
|
|
*/
|
|
WARN_ON(pq & 2);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* If P was set, adjust state to PQ=11 to indicate
|
|
* that a resend is needed for the interrupt to reach
|
|
* the guest. Also remember the value of P.
|
|
*
|
|
* This also tells us that it's in flight to a host queue
|
|
* or has already been fetched but hasn't been EOIed yet
|
|
* by the host. This it's potentially using up a host
|
|
* queue slot. This is important to know because as long
|
|
* as this is the case, we must not hard-unmask it when
|
|
* "returning" that interrupt to the host.
|
|
*
|
|
* 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;
|
|
|
|
/*
|
|
* Sync the XIVE source HW to ensure the interrupt
|
|
* has gone through the EAS before we change its
|
|
* target to the guest. That should guarantee us
|
|
* that we *will* eventually get an EOI for it on
|
|
* the host. Otherwise there would be a small window
|
|
* for P to be seen here but the interrupt going
|
|
* to the guest queue.
|
|
*/
|
|
if (xive_ops->sync_source)
|
|
xive_ops->sync_source(hw_irq);
|
|
} else
|
|
xd->saved_p = false;
|
|
} else {
|
|
irqd_clr_forwarded_to_vcpu(d);
|
|
|
|
/* No host target ? hard mask and return */
|
|
if (xd->target == XIVE_INVALID_TARGET) {
|
|
xive_do_source_set_mask(xd, true);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Sync the XIVE source HW to ensure the interrupt
|
|
* has gone through the EAS before we change its
|
|
* target to the host.
|
|
*/
|
|
if (xive_ops->sync_source)
|
|
xive_ops->sync_source(hw_irq);
|
|
|
|
/*
|
|
* By convention we are called with the interrupt in
|
|
* a PQ=10 or PQ=11 state, ie, it won't fire and will
|
|
* have latched in Q whether there's a pending HW
|
|
* interrupt or not.
|
|
*
|
|
* First reconfigure the target.
|
|
*/
|
|
rc = xive_ops->configure_irq(hw_irq,
|
|
get_hard_smp_processor_id(xd->target),
|
|
xive_irq_priority, d->irq);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/*
|
|
* Then if saved_p is not set, effectively re-enable the
|
|
* interrupt with an EOI. If it is set, we know there is
|
|
* still a message in a host queue somewhere that will be
|
|
* EOId eventually.
|
|
*
|
|
* Note: We don't check irqd_irq_disabled(). Effectively,
|
|
* we *will* let the irq get through even if masked if the
|
|
* HW is still firing it in order to deal with the whole
|
|
* saved_p business properly. If the interrupt triggers
|
|
* while masked, the generic code will re-mask it anyway.
|
|
*/
|
|
if (!xd->saved_p)
|
|
xive_do_source_eoi(hw_irq, xd);
|
|
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static struct irq_chip xive_irq_chip = {
|
|
.name = "XIVE-IRQ",
|
|
.irq_startup = xive_irq_startup,
|
|
.irq_shutdown = xive_irq_shutdown,
|
|
.irq_eoi = xive_irq_eoi,
|
|
.irq_mask = xive_irq_mask,
|
|
.irq_unmask = xive_irq_unmask,
|
|
.irq_set_affinity = xive_irq_set_affinity,
|
|
.irq_set_type = xive_irq_set_type,
|
|
.irq_retrigger = xive_irq_retrigger,
|
|
.irq_set_vcpu_affinity = xive_irq_set_vcpu_affinity,
|
|
};
|
|
|
|
bool is_xive_irq(struct irq_chip *chip)
|
|
{
|
|
return chip == &xive_irq_chip;
|
|
}
|
|
EXPORT_SYMBOL_GPL(is_xive_irq);
|
|
|
|
void xive_cleanup_irq_data(struct xive_irq_data *xd)
|
|
{
|
|
if (xd->eoi_mmio) {
|
|
iounmap(xd->eoi_mmio);
|
|
if (xd->eoi_mmio == xd->trig_mmio)
|
|
xd->trig_mmio = NULL;
|
|
xd->eoi_mmio = NULL;
|
|
}
|
|
if (xd->trig_mmio) {
|
|
iounmap(xd->trig_mmio);
|
|
xd->trig_mmio = NULL;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(xive_cleanup_irq_data);
|
|
|
|
static int xive_irq_alloc_data(unsigned int virq, irq_hw_number_t hw)
|
|
{
|
|
struct xive_irq_data *xd;
|
|
int rc;
|
|
|
|
xd = kzalloc(sizeof(struct xive_irq_data), GFP_KERNEL);
|
|
if (!xd)
|
|
return -ENOMEM;
|
|
rc = xive_ops->populate_irq_data(hw, xd);
|
|
if (rc) {
|
|
kfree(xd);
|
|
return rc;
|
|
}
|
|
xd->target = XIVE_INVALID_TARGET;
|
|
irq_set_handler_data(virq, xd);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void xive_irq_free_data(unsigned int virq)
|
|
{
|
|
struct xive_irq_data *xd = irq_get_handler_data(virq);
|
|
|
|
if (!xd)
|
|
return;
|
|
irq_set_handler_data(virq, NULL);
|
|
xive_cleanup_irq_data(xd);
|
|
kfree(xd);
|
|
}
|
|
|
|
#ifdef CONFIG_SMP
|
|
|
|
static void xive_cause_ipi(int cpu)
|
|
{
|
|
struct xive_cpu *xc;
|
|
struct xive_irq_data *xd;
|
|
|
|
xc = per_cpu(xive_cpu, cpu);
|
|
|
|
DBG_VERBOSE("IPI CPU %d -> %d (HW IRQ 0x%x)\n",
|
|
smp_processor_id(), cpu, xc->hw_ipi);
|
|
|
|
xd = &xc->ipi_data;
|
|
if (WARN_ON(!xd->trig_mmio))
|
|
return;
|
|
out_be64(xd->trig_mmio, 0);
|
|
}
|
|
|
|
static irqreturn_t xive_muxed_ipi_action(int irq, void *dev_id)
|
|
{
|
|
return smp_ipi_demux();
|
|
}
|
|
|
|
static void xive_ipi_eoi(struct irq_data *d)
|
|
{
|
|
struct xive_cpu *xc = __this_cpu_read(xive_cpu);
|
|
|
|
DBG_VERBOSE("IPI eoi: irq=%d [0x%lx] (HW IRQ 0x%x) pending=%02x\n",
|
|
d->irq, irqd_to_hwirq(d), xc->hw_ipi, xc->pending_prio);
|
|
|
|
/* Handle possible race with unplug and drop stale IPIs */
|
|
if (!xc)
|
|
return;
|
|
xive_do_source_eoi(xc->hw_ipi, &xc->ipi_data);
|
|
xive_do_queue_eoi(xc);
|
|
}
|
|
|
|
static void xive_ipi_do_nothing(struct irq_data *d)
|
|
{
|
|
/*
|
|
* Nothing to do, we never mask/unmask IPIs, but the callback
|
|
* has to exist for the struct irq_chip.
|
|
*/
|
|
}
|
|
|
|
static struct irq_chip xive_ipi_chip = {
|
|
.name = "XIVE-IPI",
|
|
.irq_eoi = xive_ipi_eoi,
|
|
.irq_mask = xive_ipi_do_nothing,
|
|
.irq_unmask = xive_ipi_do_nothing,
|
|
};
|
|
|
|
static void __init xive_request_ipi(void)
|
|
{
|
|
unsigned int virq;
|
|
|
|
/*
|
|
* Initialization failed, move on, we might manage to
|
|
* reach the point where we display our errors before
|
|
* the system falls appart
|
|
*/
|
|
if (!xive_irq_domain)
|
|
return;
|
|
|
|
/* Initialize it */
|
|
virq = irq_create_mapping(xive_irq_domain, 0);
|
|
xive_ipi_irq = virq;
|
|
|
|
WARN_ON(request_irq(virq, xive_muxed_ipi_action,
|
|
IRQF_PERCPU | IRQF_NO_THREAD, "IPI", NULL));
|
|
}
|
|
|
|
static int xive_setup_cpu_ipi(unsigned int cpu)
|
|
{
|
|
struct xive_cpu *xc;
|
|
int rc;
|
|
|
|
pr_debug("Setting up IPI for CPU %d\n", cpu);
|
|
|
|
xc = per_cpu(xive_cpu, cpu);
|
|
|
|
/* Check if we are already setup */
|
|
if (xc->hw_ipi != 0)
|
|
return 0;
|
|
|
|
/* Grab an IPI from the backend, this will populate xc->hw_ipi */
|
|
if (xive_ops->get_ipi(cpu, xc))
|
|
return -EIO;
|
|
|
|
/*
|
|
* Populate the IRQ data in the xive_cpu structure and
|
|
* configure the HW / enable the IPIs.
|
|
*/
|
|
rc = xive_ops->populate_irq_data(xc->hw_ipi, &xc->ipi_data);
|
|
if (rc) {
|
|
pr_err("Failed to populate IPI data on CPU %d\n", cpu);
|
|
return -EIO;
|
|
}
|
|
rc = xive_ops->configure_irq(xc->hw_ipi,
|
|
get_hard_smp_processor_id(cpu),
|
|
xive_irq_priority, xive_ipi_irq);
|
|
if (rc) {
|
|
pr_err("Failed to map IPI CPU %d\n", cpu);
|
|
return -EIO;
|
|
}
|
|
pr_devel("CPU %d HW IPI %x, virq %d, trig_mmio=%p\n", cpu,
|
|
xc->hw_ipi, xive_ipi_irq, xc->ipi_data.trig_mmio);
|
|
|
|
/* Unmask it */
|
|
xive_do_source_set_mask(&xc->ipi_data, false);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void xive_cleanup_cpu_ipi(unsigned int cpu, struct xive_cpu *xc)
|
|
{
|
|
/* Disable the IPI and free the IRQ data */
|
|
|
|
/* Already cleaned up ? */
|
|
if (xc->hw_ipi == 0)
|
|
return;
|
|
|
|
/* Mask the IPI */
|
|
xive_do_source_set_mask(&xc->ipi_data, true);
|
|
|
|
/*
|
|
* Note: We don't call xive_cleanup_irq_data() to free
|
|
* the mappings as this is called from an IPI on kexec
|
|
* which is not a safe environment to call iounmap()
|
|
*/
|
|
|
|
/* Deconfigure/mask in the backend */
|
|
xive_ops->configure_irq(xc->hw_ipi, hard_smp_processor_id(),
|
|
0xff, xive_ipi_irq);
|
|
|
|
/* Free the IPIs in the backend */
|
|
xive_ops->put_ipi(cpu, xc);
|
|
}
|
|
|
|
void __init xive_smp_probe(void)
|
|
{
|
|
smp_ops->cause_ipi = xive_cause_ipi;
|
|
|
|
/* Register the IPI */
|
|
xive_request_ipi();
|
|
|
|
/* Allocate and setup IPI for the boot CPU */
|
|
xive_setup_cpu_ipi(smp_processor_id());
|
|
}
|
|
|
|
#endif /* CONFIG_SMP */
|
|
|
|
static int xive_irq_domain_map(struct irq_domain *h, unsigned int virq,
|
|
irq_hw_number_t hw)
|
|
{
|
|
int rc;
|
|
|
|
/*
|
|
* Mark interrupts as edge sensitive by default so that resend
|
|
* actually works. Will fix that up below if needed.
|
|
*/
|
|
irq_clear_status_flags(virq, IRQ_LEVEL);
|
|
|
|
#ifdef CONFIG_SMP
|
|
/* IPIs are special and come up with HW number 0 */
|
|
if (hw == 0) {
|
|
/*
|
|
* IPIs are marked per-cpu. We use separate HW interrupts under
|
|
* the hood but associated with the same "linux" interrupt
|
|
*/
|
|
irq_set_chip_and_handler(virq, &xive_ipi_chip,
|
|
handle_percpu_irq);
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
rc = xive_irq_alloc_data(virq, hw);
|
|
if (rc)
|
|
return rc;
|
|
|
|
irq_set_chip_and_handler(virq, &xive_irq_chip, handle_fasteoi_irq);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void xive_irq_domain_unmap(struct irq_domain *d, unsigned int virq)
|
|
{
|
|
struct irq_data *data = irq_get_irq_data(virq);
|
|
unsigned int hw_irq;
|
|
|
|
/* XXX Assign BAD number */
|
|
if (!data)
|
|
return;
|
|
hw_irq = (unsigned int)irqd_to_hwirq(data);
|
|
if (hw_irq)
|
|
xive_irq_free_data(virq);
|
|
}
|
|
|
|
static int xive_irq_domain_xlate(struct irq_domain *h, struct device_node *ct,
|
|
const u32 *intspec, unsigned int intsize,
|
|
irq_hw_number_t *out_hwirq, unsigned int *out_flags)
|
|
|
|
{
|
|
*out_hwirq = intspec[0];
|
|
|
|
/*
|
|
* If intsize is at least 2, we look for the type in the second cell,
|
|
* we assume the LSB indicates a level interrupt.
|
|
*/
|
|
if (intsize > 1) {
|
|
if (intspec[1] & 1)
|
|
*out_flags = IRQ_TYPE_LEVEL_LOW;
|
|
else
|
|
*out_flags = IRQ_TYPE_EDGE_RISING;
|
|
} else
|
|
*out_flags = IRQ_TYPE_LEVEL_LOW;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int xive_irq_domain_match(struct irq_domain *h, struct device_node *node,
|
|
enum irq_domain_bus_token bus_token)
|
|
{
|
|
return xive_ops->match(node);
|
|
}
|
|
|
|
static const struct irq_domain_ops xive_irq_domain_ops = {
|
|
.match = xive_irq_domain_match,
|
|
.map = xive_irq_domain_map,
|
|
.unmap = xive_irq_domain_unmap,
|
|
.xlate = xive_irq_domain_xlate,
|
|
};
|
|
|
|
static void __init xive_init_host(void)
|
|
{
|
|
xive_irq_domain = irq_domain_add_nomap(NULL, XIVE_MAX_IRQ,
|
|
&xive_irq_domain_ops, NULL);
|
|
if (WARN_ON(xive_irq_domain == NULL))
|
|
return;
|
|
irq_set_default_host(xive_irq_domain);
|
|
}
|
|
|
|
static void xive_cleanup_cpu_queues(unsigned int cpu, struct xive_cpu *xc)
|
|
{
|
|
if (xc->queue[xive_irq_priority].qpage)
|
|
xive_ops->cleanup_queue(cpu, xc, xive_irq_priority);
|
|
}
|
|
|
|
static int xive_setup_cpu_queues(unsigned int cpu, struct xive_cpu *xc)
|
|
{
|
|
int rc = 0;
|
|
|
|
/* We setup 1 queues for now with a 64k page */
|
|
if (!xc->queue[xive_irq_priority].qpage)
|
|
rc = xive_ops->setup_queue(cpu, xc, xive_irq_priority);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static int xive_prepare_cpu(unsigned int cpu)
|
|
{
|
|
struct xive_cpu *xc;
|
|
|
|
xc = per_cpu(xive_cpu, cpu);
|
|
if (!xc) {
|
|
struct device_node *np;
|
|
|
|
xc = kzalloc_node(sizeof(struct xive_cpu),
|
|
GFP_KERNEL, cpu_to_node(cpu));
|
|
if (!xc)
|
|
return -ENOMEM;
|
|
np = of_get_cpu_node(cpu, NULL);
|
|
if (np)
|
|
xc->chip_id = of_get_ibm_chip_id(np);
|
|
of_node_put(np);
|
|
|
|
per_cpu(xive_cpu, cpu) = xc;
|
|
}
|
|
|
|
/* Setup EQs if not already */
|
|
return xive_setup_cpu_queues(cpu, xc);
|
|
}
|
|
|
|
static void xive_setup_cpu(void)
|
|
{
|
|
struct xive_cpu *xc = __this_cpu_read(xive_cpu);
|
|
|
|
/* The backend might have additional things to do */
|
|
if (xive_ops->setup_cpu)
|
|
xive_ops->setup_cpu(smp_processor_id(), xc);
|
|
|
|
/* Set CPPR to 0xff to enable flow of interrupts */
|
|
xc->cppr = 0xff;
|
|
out_8(xive_tima + xive_tima_offset + TM_CPPR, 0xff);
|
|
}
|
|
|
|
#ifdef CONFIG_SMP
|
|
void xive_smp_setup_cpu(void)
|
|
{
|
|
pr_devel("SMP setup CPU %d\n", smp_processor_id());
|
|
|
|
/* This will have already been done on the boot CPU */
|
|
if (smp_processor_id() != boot_cpuid)
|
|
xive_setup_cpu();
|
|
|
|
}
|
|
|
|
int xive_smp_prepare_cpu(unsigned int cpu)
|
|
{
|
|
int rc;
|
|
|
|
/* Allocate per-CPU data and queues */
|
|
rc = xive_prepare_cpu(cpu);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* Allocate and setup IPI for the new CPU */
|
|
return xive_setup_cpu_ipi(cpu);
|
|
}
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
static void xive_flush_cpu_queue(unsigned int cpu, struct xive_cpu *xc)
|
|
{
|
|
u32 irq;
|
|
|
|
/* We assume local irqs are disabled */
|
|
WARN_ON(!irqs_disabled());
|
|
|
|
/* Check what's already in the CPU queue */
|
|
while ((irq = xive_scan_interrupts(xc, false)) != 0) {
|
|
/*
|
|
* We need to re-route that interrupt to its new destination.
|
|
* First get and lock the descriptor
|
|
*/
|
|
struct irq_desc *desc = irq_to_desc(irq);
|
|
struct irq_data *d = irq_desc_get_irq_data(desc);
|
|
struct xive_irq_data *xd;
|
|
unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
|
|
|
|
/*
|
|
* Ignore anything that isn't a XIVE irq and ignore
|
|
* IPIs, so can just be dropped.
|
|
*/
|
|
if (d->domain != xive_irq_domain || hw_irq == 0)
|
|
continue;
|
|
|
|
/*
|
|
* The IRQ should have already been re-routed, it's just a
|
|
* stale in the old queue, so re-trigger it in order to make
|
|
* it reach is new destination.
|
|
*/
|
|
#ifdef DEBUG_FLUSH
|
|
pr_info("CPU %d: Got irq %d while offline, re-sending...\n",
|
|
cpu, irq);
|
|
#endif
|
|
raw_spin_lock(&desc->lock);
|
|
xd = irq_desc_get_handler_data(desc);
|
|
|
|
/*
|
|
* For LSIs, we EOI, this will cause a resend if it's
|
|
* still asserted. Otherwise do an MSI retrigger.
|
|
*/
|
|
if (xd->flags & XIVE_IRQ_FLAG_LSI)
|
|
xive_do_source_eoi(irqd_to_hwirq(d), xd);
|
|
else
|
|
xive_irq_retrigger(d);
|
|
|
|
raw_spin_unlock(&desc->lock);
|
|
}
|
|
}
|
|
|
|
void xive_smp_disable_cpu(void)
|
|
{
|
|
struct xive_cpu *xc = __this_cpu_read(xive_cpu);
|
|
unsigned int cpu = smp_processor_id();
|
|
|
|
/* Migrate interrupts away from the CPU */
|
|
irq_migrate_all_off_this_cpu();
|
|
|
|
/* Set CPPR to 0 to disable flow of interrupts */
|
|
xc->cppr = 0;
|
|
out_8(xive_tima + xive_tima_offset + TM_CPPR, 0);
|
|
|
|
/* Flush everything still in the queue */
|
|
xive_flush_cpu_queue(cpu, xc);
|
|
|
|
/* Re-enable CPPR */
|
|
xc->cppr = 0xff;
|
|
out_8(xive_tima + xive_tima_offset + TM_CPPR, 0xff);
|
|
}
|
|
|
|
void xive_flush_interrupt(void)
|
|
{
|
|
struct xive_cpu *xc = __this_cpu_read(xive_cpu);
|
|
unsigned int cpu = smp_processor_id();
|
|
|
|
/* Called if an interrupt occurs while the CPU is hot unplugged */
|
|
xive_flush_cpu_queue(cpu, xc);
|
|
}
|
|
|
|
#endif /* CONFIG_HOTPLUG_CPU */
|
|
|
|
#endif /* CONFIG_SMP */
|
|
|
|
void xive_teardown_cpu(void)
|
|
{
|
|
struct xive_cpu *xc = __this_cpu_read(xive_cpu);
|
|
unsigned int cpu = smp_processor_id();
|
|
|
|
/* Set CPPR to 0 to disable flow of interrupts */
|
|
xc->cppr = 0;
|
|
out_8(xive_tima + xive_tima_offset + TM_CPPR, 0);
|
|
|
|
if (xive_ops->teardown_cpu)
|
|
xive_ops->teardown_cpu(cpu, xc);
|
|
|
|
#ifdef CONFIG_SMP
|
|
/* Get rid of IPI */
|
|
xive_cleanup_cpu_ipi(cpu, xc);
|
|
#endif
|
|
|
|
/* Disable and free the queues */
|
|
xive_cleanup_cpu_queues(cpu, xc);
|
|
}
|
|
|
|
void xive_kexec_teardown_cpu(int secondary)
|
|
{
|
|
struct xive_cpu *xc = __this_cpu_read(xive_cpu);
|
|
unsigned int cpu = smp_processor_id();
|
|
|
|
/* Set CPPR to 0 to disable flow of interrupts */
|
|
xc->cppr = 0;
|
|
out_8(xive_tima + xive_tima_offset + TM_CPPR, 0);
|
|
|
|
/* Backend cleanup if any */
|
|
if (xive_ops->teardown_cpu)
|
|
xive_ops->teardown_cpu(cpu, xc);
|
|
|
|
#ifdef CONFIG_SMP
|
|
/* Get rid of IPI */
|
|
xive_cleanup_cpu_ipi(cpu, xc);
|
|
#endif
|
|
|
|
/* Disable and free the queues */
|
|
xive_cleanup_cpu_queues(cpu, xc);
|
|
}
|
|
|
|
void xive_shutdown(void)
|
|
{
|
|
xive_ops->shutdown();
|
|
}
|
|
|
|
bool __init xive_core_init(const struct xive_ops *ops, void __iomem *area, u32 offset,
|
|
u8 max_prio)
|
|
{
|
|
xive_tima = area;
|
|
xive_tima_offset = offset;
|
|
xive_ops = ops;
|
|
xive_irq_priority = max_prio;
|
|
|
|
ppc_md.get_irq = xive_get_irq;
|
|
__xive_enabled = true;
|
|
|
|
pr_devel("Initializing host..\n");
|
|
xive_init_host();
|
|
|
|
pr_devel("Initializing boot CPU..\n");
|
|
|
|
/* Allocate per-CPU data and queues */
|
|
xive_prepare_cpu(smp_processor_id());
|
|
|
|
/* Get ready for interrupts */
|
|
xive_setup_cpu();
|
|
|
|
pr_info("Interrupt handling initialized with %s backend\n",
|
|
xive_ops->name);
|
|
pr_info("Using priority %d for all interrupts\n", max_prio);
|
|
|
|
return true;
|
|
}
|
|
|
|
__be32 *xive_queue_page_alloc(unsigned int cpu, u32 queue_shift)
|
|
{
|
|
unsigned int alloc_order;
|
|
struct page *pages;
|
|
__be32 *qpage;
|
|
|
|
alloc_order = xive_alloc_order(queue_shift);
|
|
pages = alloc_pages_node(cpu_to_node(cpu), GFP_KERNEL, alloc_order);
|
|
if (!pages)
|
|
return ERR_PTR(-ENOMEM);
|
|
qpage = (__be32 *)page_address(pages);
|
|
memset(qpage, 0, 1 << queue_shift);
|
|
|
|
return qpage;
|
|
}
|
|
|
|
static int __init xive_off(char *arg)
|
|
{
|
|
xive_cmdline_disabled = true;
|
|
return 0;
|
|
}
|
|
__setup("xive=off", xive_off);
|