/* * linux/kernel/irq/autoprobe.c * * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar * * This file contains the interrupt probing code and driver APIs. */ #include #include #include #include #include #include "internals.h" /* * Autodetection depends on the fact that any interrupt that * comes in on to an unassigned handler will get stuck with * "IRQS_WAITING" cleared and the interrupt disabled. */ static DEFINE_MUTEX(probing_active); /** * probe_irq_on - begin an interrupt autodetect * * Commence probing for an interrupt. The interrupts are scanned * and a mask of potential interrupt lines is returned. * */ unsigned long probe_irq_on(void) { struct irq_desc *desc; unsigned long mask = 0; int i; /* * quiesce the kernel, or at least the asynchronous portion */ async_synchronize_full(); mutex_lock(&probing_active); /* * something may have generated an irq long ago and we want to * flush such a longstanding irq before considering it as spurious. */ for_each_irq_desc_reverse(i, desc) { raw_spin_lock_irq(&desc->lock); if (!desc->action && irq_settings_can_probe(desc)) { /* * Some chips need to know about probing in * progress: */ if (desc->irq_data.chip->irq_set_type) desc->irq_data.chip->irq_set_type(&desc->irq_data, IRQ_TYPE_PROBE); irq_startup(desc, false); } raw_spin_unlock_irq(&desc->lock); } /* Wait for longstanding interrupts to trigger. */ msleep(20); /* * enable any unassigned irqs * (we must startup again here because if a longstanding irq * happened in the previous stage, it may have masked itself) */ for_each_irq_desc_reverse(i, desc) { raw_spin_lock_irq(&desc->lock); if (!desc->action && irq_settings_can_probe(desc)) { desc->istate |= IRQS_AUTODETECT | IRQS_WAITING; if (irq_startup(desc, false)) desc->istate |= IRQS_PENDING; } raw_spin_unlock_irq(&desc->lock); } /* * Wait for spurious interrupts to trigger */ msleep(100); /* * Now filter out any obviously spurious interrupts */ for_each_irq_desc(i, desc) { raw_spin_lock_irq(&desc->lock); if (desc->istate & IRQS_AUTODETECT) { /* It triggered already - consider it spurious. */ if (!(desc->istate & IRQS_WAITING)) { desc->istate &= ~IRQS_AUTODETECT; irq_shutdown(desc); } else if (i < 32) mask |= 1 << i; } raw_spin_unlock_irq(&desc->lock); } return mask; } EXPORT_SYMBOL(probe_irq_on); /** * probe_irq_mask - scan a bitmap of interrupt lines * @val: mask of interrupts to consider * * Scan the interrupt lines and return a bitmap of active * autodetect interrupts. The interrupt probe logic state * is then returned to its previous value. * * Note: we need to scan all the irq's even though we will * only return autodetect irq numbers - just so that we reset * them all to a known state. */ unsigned int probe_irq_mask(unsigned long val) { unsigned int mask = 0; struct irq_desc *desc; int i; for_each_irq_desc(i, desc) { raw_spin_lock_irq(&desc->lock); if (desc->istate & IRQS_AUTODETECT) { if (i < 16 && !(desc->istate & IRQS_WAITING)) mask |= 1 << i; desc->istate &= ~IRQS_AUTODETECT; irq_shutdown(desc); } raw_spin_unlock_irq(&desc->lock); } mutex_unlock(&probing_active); return mask & val; } EXPORT_SYMBOL(probe_irq_mask); /** * probe_irq_off - end an interrupt autodetect * @val: mask of potential interrupts (unused) * * Scans the unused interrupt lines and returns the line which * appears to have triggered the interrupt. If no interrupt was * found then zero is returned. If more than one interrupt is * found then minus the first candidate is returned to indicate * their is doubt. * * The interrupt probe logic state is returned to its previous * value. * * BUGS: When used in a module (which arguably shouldn't happen) * nothing prevents two IRQ probe callers from overlapping. The * results of this are non-optimal. */ int probe_irq_off(unsigned long val) { int i, irq_found = 0, nr_of_irqs = 0; struct irq_desc *desc; for_each_irq_desc(i, desc) { raw_spin_lock_irq(&desc->lock); if (desc->istate & IRQS_AUTODETECT) { if (!(desc->istate & IRQS_WAITING)) { if (!nr_of_irqs) irq_found = i; nr_of_irqs++; } desc->istate &= ~IRQS_AUTODETECT; irq_shutdown(desc); } raw_spin_unlock_irq(&desc->lock); } mutex_unlock(&probing_active); if (nr_of_irqs > 1) irq_found = -irq_found; return irq_found; } EXPORT_SYMBOL(probe_irq_off); pt>
authorThomas Gleixner <tglx@linutronix.de>2017-01-31 23:58:38 +0100
committerIngo Molnar <mingo@kernel.org>2017-02-01 08:37:27 +0100
commitdd86e373e09fb16b83e8adf5c48c421a4ca76468 (patch)
tree55703c2ea8584e303e342090614e0aab3509ab21 /sound/soc/fsl/imx-es8328.c
parent0b3589be9b98994ce3d5aeca52445d1f5627c4ba (diff)
perf/x86/intel/rapl: Make package handling more robust
The package management code in RAPL relies on package mapping being available before a CPU is started. This changed with: 9d85eb9119f4 ("x86/smpboot: Make logical package management more robust") because the ACPI/BIOS information turned out to be unreliable, but that left RAPL in broken state. This was not noticed because on a regular boot all CPUs are online before RAPL is initialized. A possible fix would be to reintroduce the mess which allocates a package data structure in CPU prepare and when it turns out to already exist in starting throw it away later in the CPU online callback. But that's a horrible hack and not required at all because RAPL becomes functional for perf only in the CPU online callback. That's correct because user space is not yet informed about the CPU being onlined, so nothing caan rely on RAPL being available on that particular CPU. Move the allocation to the CPU online callback and simplify the hotplug handling. At this point the package mapping is established and correct. This also adds a missing check for available package data in the event_init() function. Reported-by: Yasuaki Ishimatsu <yasu.isimatu@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Stephane Eranian <eranian@google.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: 9d85eb9119f4 ("x86/smpboot: Make logical package management more robust") Link: http://lkml.kernel.org/r/20170131230141.212593966@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'sound/soc/fsl/imx-es8328.c')