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authorMarc Zyngier <marc.zyngier@arm.com>2015-07-28 14:46:08 +0100
committerAlex Shi <alex.shi@linaro.org>2015-11-06 15:56:43 +0800
commit49ecc762ff485605d26c1f818494363b0a0d948e (patch)
tree21164f1ba22c51d3e741b4ad2c484a23ab2ea713 /kernel
parent0f17dcb94597a691e79a916d77d6417adec7cde0 (diff)
downloadlinux-linaro-stable-49ecc762ff485605d26c1f818494363b0a0d948e.tar.gz
genirq/irqdomain: Allow irq domain aliasing
It is not uncommon (at least with the ARM stuff) to have a piece of hardware that implements different flavours of "interrupts". A typical example of this is the GICv3 ITS, which implements standard PCI/MSI support, but also some form of "generic MSI". So far, the PCI/MSI domain is registered using the ITS device_node, so that irq_find_host can return it. On the contrary, the raw MSI domain is not registered with an device_node, making it impossible to be looked up by another subsystem (obviously, using the same device_node twice would only result in confusion, as it is not defined which one irq_find_host would return). A solution to this is to "type" domains that may be aliasing, and to be able to lookup an device_node that matches a given type. For this, we introduce irq_find_matching_host() as a superset of irq_find_host: struct irq_domain *irq_find_matching_host(struct device_node *node, enum irq_domain_bus_token bus_token); where bus_token is the "type" we want to match the domain against (so far, only DOMAIN_BUS_ANY is defined). This result in some moderately invasive changes on the PPC side (which is the only user of the .match method). This has otherwise no functionnal change. Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Cc: <linux-arm-kernel@lists.infradead.org> Cc: Yijing Wang <wangyijing@huawei.com> Cc: Ma Jun <majun258@huawei.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Duc Dang <dhdang@apm.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Jason Cooper <jason@lakedaemon.net> Link: http://lkml.kernel.org/r/1438091186-10244-2-git-send-email-marc.zyngier@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> (cherry picked from commit ad3aedfbb04b3a2af54473cfe31f13953cfe9d84) Signed-off-by: Alex Shi <alex.shi@linaro.org> Conflicts solution: add arch/powerpc/platforms/powernv/opal-irqchip.c
Diffstat (limited to 'kernel')
-rw-r--r--kernel/irq/irqdomain.c18
1 files changed, 13 insertions, 5 deletions
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 7fac311057b8..021f823794e7 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -187,10 +187,12 @@ struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
EXPORT_SYMBOL_GPL(irq_domain_add_legacy);
/**
- * irq_find_host() - Locates a domain for a given device node
+ * irq_find_matching_host() - Locates a domain for a given device node
* @node: device-tree node of the interrupt controller
+ * @bus_token: domain-specific data
*/
-struct irq_domain *irq_find_host(struct device_node *node)
+struct irq_domain *irq_find_matching_host(struct device_node *node,
+ enum irq_domain_bus_token bus_token)
{
struct irq_domain *h, *found = NULL;
int rc;
@@ -199,13 +201,19 @@ struct irq_domain *irq_find_host(struct device_node *node)
* it might potentially be set to match all interrupts in
* the absence of a device node. This isn't a problem so far
* yet though...
+ *
+ * bus_token == DOMAIN_BUS_ANY matches any domain, any other
+ * values must generate an exact match for the domain to be
+ * selected.
*/
mutex_lock(&irq_domain_mutex);
list_for_each_entry(h, &irq_domain_list, link) {
if (h->ops->match)
- rc = h->ops->match(h, node);
+ rc = h->ops->match(h, node, bus_token);
else
- rc = (h->of_node != NULL) && (h->of_node == node);
+ rc = ((h->of_node != NULL) && (h->of_node == node) &&
+ ((bus_token == DOMAIN_BUS_ANY) ||
+ (h->bus_token == bus_token)));
if (rc) {
found = h;
@@ -215,7 +223,7 @@ struct irq_domain *irq_find_host(struct device_node *node)
mutex_unlock(&irq_domain_mutex);
return found;
}
-EXPORT_SYMBOL_GPL(irq_find_host);
+EXPORT_SYMBOL_GPL(irq_find_matching_host);
/**
* irq_set_default_host() - Set a "default" irq domain