[PATCH v5 01/19] genirq: irqdomain: Allow irq domain aliasing

Marc Zyngier
2015-07-23T09:32:26Z

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.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/powerpc/platforms/512x/mpc5121_ads_cpld.c | 3 ++-
arch/powerpc/platforms/cell/interrupt.c | 3 ++-
arch/powerpc/platforms/embedded6xx/flipper-pic.c | 3 ++-
arch/powerpc/platforms/powermac/pic.c | 3 ++-
arch/powerpc/platforms/powernv/opal-irqchip.c | 3 ++-
arch/powerpc/platforms/ps3/interrupt.c | 3 ++-
arch/powerpc/sysdev/ehv_pic.c | 3 ++-
arch/powerpc/sysdev/i8259.c | 3 ++-
arch/powerpc/sysdev/ipic.c | 3 ++-
arch/powerpc/sysdev/mpic.c | 3 ++-
arch/powerpc/sysdev/qe_lib/qe_ic.c | 3 ++-
arch/powerpc/sysdev/xics/xics-common.c | 3 ++-
include/linux/irqdomain.h | 23 +++++++++++++++++++++--
kernel/irq/irqdomain.c | 18 +++++++++++++-----
14 files changed, 58 insertions(+), 19 deletions(-)

diff --git a/arch/powerpc/platforms/512x/mpc5121_ads_cpld.c b/arch/powerpc/platforms/512x/mpc5121_ads_cpld.c
index ca3a062..11090ab 100644
--- a/arch/powerpc/platforms/512x/mpc5121_ads_cpld.c
+++ b/arch/powerpc/platforms/512x/mpc5121_ads_cpld.c
@@ -123,7 +123,8 @@ cpld_pic_cascade(unsigned int irq, struct irq_desc *desc)
}

static int
-cpld_pic_host_match(struct irq_domain *h, struct device_node *node)
+cpld_pic_host_match(struct irq_domain *h, struct device_node *node,
+ enum irq_domain_bus_token bus_token)
{
return cpld_pic_node == node;
}
diff --git a/arch/powerpc/platforms/cell/interrupt.c b/arch/powerpc/platforms/cell/interrupt.c
index 3af8324..a15f1ef 100644
--- a/arch/powerpc/platforms/cell/interrupt.c
+++ b/arch/powerpc/platforms/cell/interrupt.c
@@ -222,7 +222,8 @@ void iic_request_IPIs(void)
#endif /* CONFIG_SMP */

-static int iic_host_match(struct irq_domain *h, struct device_node *node)
+static int iic_host_match(struct irq_domain *h, struct device_node *node,
+ enum irq_domain_bus_token bus_token)
{
return of_device_is_compatible(node,
"IBM,CBEA-Internal-Interrupt-Controller");
diff --git a/arch/powerpc/platforms/embedded6xx/flipper-pic.c b/arch/powerpc/platforms/embedded6xx/flipper-pic.c
index 4cde8e7..b7866e0 100644
--- a/arch/powerpc/platforms/embedded6xx/flipper-pic.c
+++ b/arch/powerpc/platforms/embedded6xx/flipper-pic.c
@@ -108,7 +108,8 @@ static int flipper_pic_map(struct irq_domain *h, unsigned int virq,
return 0;
}

-static int flipper_pic_match(struct irq_domain *h, struct device_node *np)
+static int flipper_pic_match(struct irq_domain *h, struct device_node *np,
+ enum irq_domain_bus_token bus_token)
{
return 1;
}
diff --git a/arch/powerpc/platforms/powermac/pic.c b/arch/powerpc/platforms/powermac/pic.c
index 59cfc9d..6f4f8b0 100644
--- a/arch/powerpc/platforms/powermac/pic.c
+++ b/arch/powerpc/platforms/powermac/pic.c
@@ -268,7 +268,8 @@ static struct irqaction gatwick_cascade_action = {
.name = "cascade",
};

-static int pmac_pic_host_match(struct irq_domain *h, struct device_node *node)
+static int pmac_pic_host_match(struct irq_domain *h, struct device_node *node,
+ enum irq_domain_bus_token bus_token)
{
/* We match all, we don't always have a node anyway */
return 1;
diff --git a/arch/powerpc/platforms/powernv/opal-irqchip.c b/arch/powerpc/platforms/powernv/opal-irqchip.c
index e2e7d75..2c91ee7 100644
--- a/arch/powerpc/platforms/powernv/opal-irqchip.c
+++ b/arch/powerpc/platforms/powernv/opal-irqchip.c
@@ -134,7 +134,8 @@ static void opal_handle_irq_work(struct irq_work *work)
opal_handle_events(be64_to_cpu(last_outstanding_events));
}

-static int opal_event_match(struct irq_domain *h, struct device_node *node)
+static int opal_event_match(struct irq_domain *h, struct device_node *node,
+ enum irq_domain_bus_token bus_token)
{
return h->of_node == node;
}
diff --git a/arch/powerpc/platforms/ps3/interrupt.c b/arch/powerpc/platforms/ps3/interrupt.c
index a6c42f3..638c406 100644
--- a/arch/powerpc/platforms/ps3/interrupt.c
+++ b/arch/powerpc/platforms/ps3/interrupt.c
@@ -678,7 +678,8 @@ static int ps3_host_map(struct irq_domain *h, unsigned int virq,
return 0;
}

-static int ps3_host_match(struct irq_domain *h, struct device_node *np)
+static int ps3_host_match(struct irq_domain *h, struct device_node *np,
+ enum irq_domain_bus_token bus_token)
{
/* Match all */
return 1;
diff --git a/arch/powerpc/sysdev/ehv_pic.c b/arch/powerpc/sysdev/ehv_pic.c
index 2d20f10..eca0b00 100644
--- a/arch/powerpc/sysdev/ehv_pic.c
+++ b/arch/powerpc/sysdev/ehv_pic.c
@@ -177,7 +177,8 @@ unsigned int ehv_pic_get_irq(void)
return irq_linear_revmap(global_ehv_pic->irqhost, irq);
}

-static int ehv_pic_host_match(struct irq_domain *h, struct device_node *node)
+static int ehv_pic_host_match(struct irq_domain *h, struct device_node *node,
+ enum irq_domain_bus_token bus_token)
{
/* Exact match, unless ehv_pic node is NULL */
return h->of_node == NULL || h->of_node == node;
diff --git a/arch/powerpc/sysdev/i8259.c b/arch/powerpc/sysdev/i8259.c
index 31c3347..e1a9c2c 100644
--- a/arch/powerpc/sysdev/i8259.c
+++ b/arch/powerpc/sysdev/i8259.c
@@ -162,7 +162,8 @@ static struct resource pic_edgectrl_iores = {
.flags = IORESOURCE_BUSY,
};

-static int i8259_host_match(struct irq_domain *h, struct device_node *node)
+static int i8259_host_match(struct irq_domain *h, struct device_node *node,
+ enum irq_domain_bus_token bus_token)
{
return h->of_node == NULL || h->of_node == node;
}
diff --git a/arch/powerpc/sysdev/ipic.c b/arch/powerpc/sysdev/ipic.c
index d78f136..6b2b689 100644
--- a/arch/powerpc/sysdev/ipic.c
+++ b/arch/powerpc/sysdev/ipic.c
@@ -671,7 +671,8 @@ static struct irq_chip ipic_edge_irq_chip = {
.irq_set_type = ipic_set_irq_type,
};

-static int ipic_host_match(struct irq_domain *h, struct device_node *node)
+static int ipic_host_match(struct irq_domain *h, struct device_node *node,
+ enum irq_domain_bus_token bus_token)
{
/* Exact match, unless ipic node is NULL */
return h->of_node == NULL || h->of_node == node;
diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
index c8e7333..97a8ae8 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -1007,7 +1007,8 @@ static struct irq_chip mpic_irq_ht_chip = {
#endif /* CONFIG_MPIC_U3_HT_IRQS */

-static int mpic_host_match(struct irq_domain *h, struct device_node *node)
+static int mpic_host_match(struct irq_domain *h, struct device_node *node,
+ enum irq_domain_bus_token bus_token)
{
/* Exact match, unless mpic node is NULL */
return h->of_node == NULL || h->of_node == node;
diff --git a/arch/powerpc/sysdev/qe_lib/qe_ic.c b/arch/powerpc/sysdev/qe_lib/qe_ic.c
index 6512cd8..47b352e 100644
--- a/arch/powerpc/sysdev/qe_lib/qe_ic.c
+++ b/arch/powerpc/sysdev/qe_lib/qe_ic.c
@@ -244,7 +244,8 @@ static struct irq_chip qe_ic_irq_chip = {
.irq_mask_ack = qe_ic_mask_irq,
};

-static int qe_ic_host_match(struct irq_domain *h, struct device_node *node)
+static int qe_ic_host_match(struct irq_domain *h, struct device_node *node,
+ enum irq_domain_bus_token bus_token)
{
/* Exact match, unless qe_ic node is NULL */
return h->of_node == NULL || h->of_node == node;
diff --git a/arch/powerpc/sysdev/xics/xics-common.c b/arch/powerpc/sysdev/xics/xics-common.c
index 08c248e..47e43b7 100644
--- a/arch/powerpc/sysdev/xics/xics-common.c
+++ b/arch/powerpc/sysdev/xics/xics-common.c
@@ -298,7 +298,8 @@ int xics_get_irq_server(unsigned int virq, const struct cpumask *cpumask,
}
#endif /* CONFIG_SMP */

-static int xics_host_match(struct irq_domain *h, struct device_node *node)
+static int xics_host_match(struct irq_domain *h, struct device_node *node,
+ enum irq_domain_bus_token bus_token)
{
struct ics *ics;

diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index 744ac0e..91a83ad 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -45,6 +45,17 @@ struct irq_data;
/* Number of irqs reserved for a legacy isa controller */
#define NUM_ISA_INTERRUPTS 16

+/*
+ * Should several domains have the same device node, but serve
+ * different purposes (for example one domain is for PCI/MSI, and the
+ * other for wired IRQs), they can be distinguished using a
+ * bus-specific token. Most domains are expected to only carry
+ * DOMAIN_BUS_ANY.
+ */
+enum irq_domain_bus_token {
+ DOMAIN_BUS_ANY = 0,
+};
+
/**
* struct irq_domain_ops - Methods for irq_domain objects
* @match: Match an interrupt controller device node to a host, returns
@@ -61,7 +72,8 @@ struct irq_data;
* to setup the irq_desc when returning from map().
*/
struct irq_domain_ops {
- int (*match)(struct irq_domain *d, struct device_node *node);
+ int (*match)(struct irq_domain *d, struct device_node *node,
+ enum irq_domain_bus_token bus_token);
int (*map)(struct irq_domain *d, unsigned int virq, irq_hw_number_t hw);
void (*unmap)(struct irq_domain *d, unsigned int virq);
int (*xlate)(struct irq_domain *d, struct device_node *node,
@@ -116,6 +128,7 @@ struct irq_domain {

/* Optional data */
struct device_node *of_node;
+ enum irq_domain_bus_token bus_token;
struct irq_domain_chip_generic *gc;
#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
struct irq_domain *parent;
@@ -161,9 +174,15 @@ struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
irq_hw_number_t first_hwirq,
const struct irq_domain_ops *ops,
void *host_data);
-extern struct irq_domain *irq_find_host(struct device_node *node);
+extern struct irq_domain *irq_find_matching_host(struct device_node *node,
+ enum irq_domain_bus_token bus_token);
extern void irq_set_default_host(struct irq_domain *host);

+static inline struct irq_domain *irq_find_host(struct device_node *node)
+{
+ return irq_find_matching_host(node, DOMAIN_BUS_ANY);
+}
+
/**
* irq_domain_add_linear() - Allocate and register a linear revmap irq_domain.
* @of_node: pointer to interrupt controller's device tree node.
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 8c3577f..995d217 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
+ * @data: 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
--
2.1.4