user/sven/linux.git/kernel/irq/settings.h, branch v4.9.99

genirq: Add flag to force mask in disable_irq[_nosync]()

2015-10-11T09:33:42Z

If an irq chip does not implement the irq_disable callback, then we use a lazy approach for disabling the interrupt. That means that the interrupt is marked disabled, but the interrupt line is not immediately masked in the interrupt chip. It only becomes masked if the interrupt is raised while it's marked disabled. We use this to avoid possibly expensive mask/unmask operations for common case operations. Unfortunately there are devices which do not allow the interrupt to be disabled easily at the device level. They are forced to use disable_irq_nosync(). This can result in taking each interrupt twice. Instead of enforcing the non lazy mode on all interrupts of a irq chip, provide a settings flag, which can be set by the driver for that particular interrupt line. Reported-and-tested-by: Duc Dang Signed-off-by: Thomas Gleixner Cc: Marc Zyngier Cc: Jason Cooper Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1510092348370.6097@nanos

genirq: Prevent spurious detection for unconditionally polled interrupts

2013-11-13T15:03:02Z

On a 68k platform a couple of interrupts are demultiplexed and "polled" from a top level interrupt. Unfortunately there is no way to determine which of the sub interrupts raised the top level interrupt, so all of the demultiplexed interrupt handlers need to be invoked. Given a high enough frequency this can trigger the spurious interrupt detection mechanism, if one of the demultiplex interrupts returns IRQ_NONE continuously. But this is a false positive as the polling causes this behaviour and not buggy hardware/software. Introduce IRQ_POLLED which can be set at interrupt chip setup time via irq_set_status_flags(). The flag excludes the interrupt from the spurious detector and from all core polling activities. Reported-and-tested-by: Michael Schmitz Cc: Geert Uytterhoeven Cc: linux-m68k@vger.kernel.org Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1311061149250.23353@ionos.tec.linutronix.de

genirq: Add support for per-cpu dev_id interrupts

2011-10-03T13:35:26Z

The ARM GIC interrupt controller offers per CPU interrupts (PPIs), which are usually used to connect local timers to each core. Each CPU has its own private interface to the GIC, and only sees the PPIs that are directly connect to it. While these timers are separate devices and have a separate interrupt line to a core, they all use the same IRQ number. For these devices, request_irq() is not the right API as it assumes that an IRQ number is visible by a number of CPUs (through the affinity setting), but makes it very awkward to express that an IRQ number can be handled by all CPUs, and yet be a different interrupt line on each CPU, requiring a different dev_id cookie to be passed back to the handler. The *_percpu_irq() functions is designed to overcome these limitations, by providing a per-cpu dev_id vector: int request_percpu_irq(unsigned int irq, irq_handler_t handler, const char *devname, void __percpu *percpu_dev_id); void free_percpu_irq(unsigned int, void __percpu *); int setup_percpu_irq(unsigned int irq, struct irqaction *new); void remove_percpu_irq(unsigned int irq, struct irqaction *act); void enable_percpu_irq(unsigned int irq); void disable_percpu_irq(unsigned int irq); The API has a number of limitations: - no interrupt sharing - no threading - common handler across all the CPUs Once the interrupt is requested using setup_percpu_irq() or request_percpu_irq(), it must be enabled by each core that wishes its local interrupt to be delivered. Based on an initial patch by Thomas Gleixner. Signed-off-by: Marc Zyngier Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1316793788-14500-2-git-send-email-marc.zyngier@arm.com Signed-off-by: Thomas Gleixner

genirq: Support per-IRQ thread disabling.

2011-04-23T13:56:24Z

This adds support for disabling threading on a per-IRQ basis via the IRQ status instead of the IRQ flow, which is necessary for interrupts that don't follow the natural IRQ flow channels, such as those that are virtually created. The new APIs added are simply: irq_set_thread() irq_set_nothread() which follow the rest of the IRQ status routines. Chained handlers also have IRQ_NOTHREAD set on them automatically, making the lack of threading explicit rather than implicit. Subsequently, the nothread flag can be viewed through the standard genirq debugging facilities. [ tglx: Fixed cleanup fallout ] Signed-off-by: Paul Mundt Link: http://lkml.kernel.org/r/%3C20110406210135.GF18426%40linux-sh.org%3E Signed-off-by: Thomas Gleixner

genirq: Remove compat code

2011-03-29T12:48:19Z

Signed-off-by: Thomas Gleixner

genirq: Remove desc->status when GENERIC_HARDIRQS_NO_COMPAT=y

2011-02-19T11:58:22Z

If everything uses the right accessors, then enabling GENERIC_HARDIRQS_NO_COMPAT should just work. If not it will tell you. Don't be lazy and use the trick which I use in the core code! git grep status_use_accessors will unearth it in a split second. Offenders are tracked down and not slapped with stinking trouts. This time we use frozen shark for a better educational value. Signed-off-by: Thomas Gleixner

genirq: Cleanup irq.h

2011-02-19T11:58:21Z

Put the constants into an enum and document them. Signed-off-by: Thomas Gleixner

genirq: Force wrapped access to desc->status in core code

2011-02-19T11:58:21Z

Force the usage of wrappers by another nasty CPP substitution. Signed-off-by: Thomas Gleixner

genirq: Wrap the remaning IRQ_* flags

2011-02-19T11:58:21Z

Use wrappers to keep them away from the core code. Signed-off-by: Thomas Gleixner

genirq: Mirror irq trigger type bits in irq_data.state

2011-02-19T11:58:20Z

That's the data structure chip functions get provided. Also allow them to signal the core code that they updated the flags in irq_data.state by returning IRQ_SET_MASK_OK_NOCOPY. The default is unchanged. The type bits should be accessed via: val = irqd_get_trigger_type(irqdata); and irqd_set_trigger_type(irqdata, val); Coders who access them directly will be tracked down and slapped with stinking trouts. Signed-off-by: Thomas Gleixner