summaryrefslogtreecommitdiff
path: root/include/linux/irq.h
diff options
context:
space:
mode:
authorMarc Zyngier <marc.zyngier@arm.com>2017-01-17 16:00:48 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-02-09 08:08:31 +0100
commite02136282296dbc90f3c88b1cc5202ec0d5ed9f1 (patch)
tree19b9130ef7ee0fc56a72726e4a0e412b98c49553 /include/linux/irq.h
parentc6b0333baea0acbe792c22ac71a04e40e26a8398 (diff)
irqdomain: Avoid activating interrupts more than once
commit 08d85f3ea99f1eeafc4e8507936190e86a16ee8c upstream. Since commit f3b0946d629c ("genirq/msi: Make sure PCI MSIs are activated early"), we can end-up activating a PCI/MSI twice (once at allocation time, and once at startup time). This is normally of no consequences, except that there is some HW out there that may misbehave if activate is used more than once (the GICv3 ITS, for example, uses the activate callback to issue the MAPVI command, and the architecture spec says that "If there is an existing mapping for the EventID-DeviceID combination, behavior is UNPREDICTABLE"). While this could be worked around in each individual driver, it may make more sense to tackle the issue at the core level. In order to avoid getting in that situation, let's have a per-interrupt flag to remember if we have already activated that interrupt or not. Fixes: f3b0946d629c ("genirq/msi: Make sure PCI MSIs are activated early") Reported-and-tested-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Link: http://lkml.kernel.org/r/1484668848-24361-1-git-send-email-marc.zyngier@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/irq.h')
-rw-r--r--include/linux/irq.h17
1 files changed, 17 insertions, 0 deletions
diff --git a/include/linux/irq.h b/include/linux/irq.h
index e79875574b39..39e3254e5769 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -184,6 +184,7 @@ struct irq_data {
*
* IRQD_TRIGGER_MASK - Mask for the trigger type bits
* IRQD_SETAFFINITY_PENDING - Affinity setting is pending
+ * IRQD_ACTIVATED - Interrupt has already been activated
* IRQD_NO_BALANCING - Balancing disabled for this IRQ
* IRQD_PER_CPU - Interrupt is per cpu
* IRQD_AFFINITY_SET - Interrupt affinity was set
@@ -202,6 +203,7 @@ struct irq_data {
enum {
IRQD_TRIGGER_MASK = 0xf,
IRQD_SETAFFINITY_PENDING = (1 << 8),
+ IRQD_ACTIVATED = (1 << 9),
IRQD_NO_BALANCING = (1 << 10),
IRQD_PER_CPU = (1 << 11),
IRQD_AFFINITY_SET = (1 << 12),
@@ -312,6 +314,21 @@ static inline bool irqd_affinity_is_managed(struct irq_data *d)
return __irqd_to_state(d) & IRQD_AFFINITY_MANAGED;
}
+static inline bool irqd_is_activated(struct irq_data *d)
+{
+ return __irqd_to_state(d) & IRQD_ACTIVATED;
+}
+
+static inline void irqd_set_activated(struct irq_data *d)
+{
+ __irqd_to_state(d) |= IRQD_ACTIVATED;
+}
+
+static inline void irqd_clr_activated(struct irq_data *d)
+{
+ __irqd_to_state(d) &= ~IRQD_ACTIVATED;
+}
+
#undef __irqd_to_state
static inline irq_hw_number_t irqd_to_hwirq(struct irq_data *d)