DT irq deferred probe support

PATCH In review Rob Herring 4 participants 9 messages Apr 23, 2014 – Apr 24, 2014

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Rob Herring

author

2014-04-23 22:57 UTC #0 lore raw

cover DT irq deferred probe support

From: Rob Herring <[email protected]>

This is atleast the 4th attempt to fix a long standing issue with DT irq resolution needing to support deferred probe when irq parent is not yet initialized. This version implements Russell King's suggestion to do irq resolution when platform_get_irq is called.

Tony, I squashed your warning fix (dropping the other part) and stole much of your commit message. Let me know if you have any issues with that.

Rob

Rob Herring (2):
of: selftest: add deferred probe interrupt test
of/irq: do irq resolution in platform_get_irq

 drivers/base/platform.c                        |  7 +++++-
 drivers/of/irq.c                               | 26 +++++++++++++++++++++
 drivers/of/platform.c                          |  4 +++-
 drivers/of/selftest.c                          | 32 ++++++++++++++++++++++++++
 drivers/of/testcase-data/tests-interrupts.dtsi | 12 ++++++++++
 include/linux/of_irq.h                         |  7 +++++-
 6 files changed, 85 insertions(+), 3 deletions(-)

Signature · 1 line

1.9.1

Rob Herring

author

2014-04-23 22:57 UTC #1 lore raw

PATCH 1/2 of: selftest: add deferred probe interrupt test

From: Rob Herring <[email protected]>

Signed-off-by Rob Herring <[email protected]>

---
 drivers/of/selftest.c                          | 32 ++++++++++++++++++++++++++
 drivers/of/testcase-data/tests-interrupts.dtsi | 12 ++++++++++
 2 files changed, 44 insertions(+)

drivers/of/selftest.c +32 -0

index ae44500..fe70b86 100644
@@ -10,6 +10,7 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_irq.h>
+#include <linux/of_platform.h>
 #include <linux/list.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>

@@ -427,6 +428,36 @@ static void __init of_selftest_match_node(void)
 	}
 }
 
+static void __init of_selftest_platform_populate(void)
+{
+	int irq;
+	struct device_node *np;
+	struct platform_device *pdev;
+
+	np = of_find_node_by_path("/testcase-data");
+	of_platform_populate(np, of_default_bus_match_table, NULL, NULL);
+
+	/* Test that a missing irq domain returns -EPROBE_DEFER */
+	np = of_find_node_by_path("/testcase-data/testcase-device1");
+	pdev = of_find_device_by_node(np);
+	if (!pdev)
+		selftest(0, "device 1 creation failed\n");
+	irq = platform_get_irq(pdev, 0);
+	if (irq != -EPROBE_DEFER)
+		selftest(0, "device deferred probe failed - %d\n", irq);
+
+	/* Test that a parsing failure does not return -EPROBE_DEFER */
+	np = of_find_node_by_path("/testcase-data/testcase-device2");
+	pdev = of_find_device_by_node(np);
+	if (!pdev)
+		selftest(0, "device 2 creation failed\n");
+	irq = platform_get_irq(pdev, 0);
+	if (irq >= 0 || irq == -EPROBE_DEFER)
+		selftest(0, "device parsing error failed - %d\n", irq);
+
+	selftest(1, "passed");
+}
+
 static int __init of_selftest(void)
 {
 	struct device_node *np;

@@ -445,6 +476,7 @@ static int __init of_selftest(void)
 	of_selftest_parse_interrupts();
 	of_selftest_parse_interrupts_extended();
 	of_selftest_match_node();
+	of_selftest_platform_populate();
 	pr_info("end of selftest - %i passed, %i failed\n",
 		selftest_results.passed, selftest_results.failed);
 	return 0;

drivers/of/testcase-data/tests-interrupts.dtsi +12 -0

index c843720..45cbdf8 100644
@@ -54,5 +54,17 @@
 						      <&test_intmap1 1 2>;
 			};
 		};
+
+		testcase-device1 {
+			compatible = "testcase-device";
+			interrupt-parent = <&test_intc0>;
+			interrupts = <1>;
+		};
+
+		testcase-device2 {
+			compatible = "testcase-device";
+			interrupts = <1>;
+		};
 	};
+
 };

Signature · 1 line

1.9.1

Rob Herring

author

2014-04-23 22:57 UTC #2 lore raw

PATCH 2/2 of/irq: do irq resolution in platform_get_irq

In reply to Rob Herring

From: Rob Herring <[email protected]>

Currently we get the following kind of errors if we try to use interrupt phandles to irqchips that have not yet initialized:

irq: no irq domain found for /ocp/pinmux at 48002030 !

------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at drivers/of/platform.c:171 of_device_alloc+0x144/0x184()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.12.0-00038-g42a9708 #1012
(show_stack+0x14/0x1c)
(dump_stack+0x6c/0xa0)
(warn_slowpath_common+0x64/0x84)
(warn_slowpath_null+0x1c/0x24)
(of_device_alloc+0x144/0x184)
(of_platform_device_create_pdata+0x44/0x9c)
(of_platform_bus_create+0xd0/0x170)
(of_platform_bus_create+0x12c/0x170)
(of_platform_populate+0x60/0x98)

This is because we're wrongly trying to populate resources that are not yet available. It's perfectly valid to create irqchips dynamically, so let's fix up the issue by resolving the interrupt resources when platform_get_irq is called.

And then we also need to accept the fact that some irqdomains do not exist that early on, and only get initialized later on. So we can make the current WARN_ON into just into a pr_debug().

We still attempt to populate irq resources when we create the devices. This allows current drivers which don't use platform_get_irq to continue to function. Once all drivers are fixed, this code can be removed.

Signed-off-by Rob Herring <[email protected]>

Signed-off-by Tony Lindgren <[email protected]>

---
 drivers/base/platform.c |  7 ++++++-
 drivers/of/irq.c        | 26 ++++++++++++++++++++++++++
 drivers/of/platform.c   |  4 +++-
 include/linux/of_irq.h  |  7 ++++++-
 4 files changed, 41 insertions(+), 3 deletions(-)

drivers/base/platform.c +6 -1

index e714709..5b47210 100644
@@ -13,6 +13,7 @@
 #include <linux/string.h>
 #include <linux/platform_device.h>
 #include <linux/of_device.h>
+#include <linux/of_irq.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/dma-mapping.h>

@@ -87,7 +88,11 @@ int platform_get_irq(struct platform_device *dev, unsigned int num)
 		return -ENXIO;
 	return dev->archdata.irqs[num];
 #else
-	struct resource *r = platform_get_resource(dev, IORESOURCE_IRQ, num);
+	struct resource *r;
+	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node)
+		return of_irq_get(dev->dev.of_node, num);
+
+	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
 
 	return r ? r->start : -ENXIO;
 #endif

drivers/of/irq.c +26 -0

index 9bcf2cf..ca01893 100644
@@ -380,6 +380,32 @@ int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
 EXPORT_SYMBOL_GPL(of_irq_to_resource);
 
 /**
+ * of_irq_get - Decode a node's IRQ and return it as a Linux irq number
+ * @dev: pointer to device tree node
+ * @index: zero-based index of the irq
+ *
+ * Returns Linux irq number on success, or -EPROBE_DEFER if the irq domain
+ * is not yet created.
+ *
+ */
+int of_irq_get(struct device_node *dev, int index)
+{
+	int rc;
+	struct of_phandle_args oirq;
+	struct irq_domain *domain;
+
+	rc = of_irq_parse_one(dev, index, &oirq);
+	if (rc)
+		return rc;
+
+	domain = irq_find_host(oirq.np);
+	if (!domain)
+		return -EPROBE_DEFER;
+
+	return irq_create_of_mapping(&oirq);
+}
+
+/**
  * of_irq_count - Count the number of IRQs a node uses
  * @dev: pointer to device tree node
  */

drivers/of/platform.c +3 -1

index 404d1da..bd47fbc 100644
@@ -168,7 +168,9 @@ struct platform_device *of_device_alloc(struct device_node *np,
 			rc = of_address_to_resource(np, i, res);
 			WARN_ON(rc);
 		}
-		WARN_ON(of_irq_to_resource_table(np, res, num_irq) != num_irq);
+		if (of_irq_to_resource_table(np, res, num_irq) != num_irq)
+			pr_debug("not all legacy IRQ resources mapped for %s\n",
+				 np->name);
 	}
 
 	dev->dev.of_node = of_node_get(np);

include/linux/of_irq.h +6 -1

index 3f23b44..bc9e51a 100644
@@ -34,21 +34,26 @@ static inline int of_irq_parse_oldworld(struct device_node *device, int index,
 extern int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq);
 extern int of_irq_parse_one(struct device_node *device, int index,
 			  struct of_phandle_args *out_irq);
-extern unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data);
 extern int of_irq_to_resource(struct device_node *dev, int index,
 			      struct resource *r);
 extern int of_irq_to_resource_table(struct device_node *dev,
 		struct resource *res, int nr_irqs);
+extern unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data);
 
 extern void of_irq_init(const struct of_device_id *matches);
 
 #ifdef CONFIG_OF_IRQ
 extern int of_irq_count(struct device_node *dev);
+extern int of_irq_get(struct device_node *dev, int index);
 #else
 static inline int of_irq_count(struct device_node *dev)
 {
 	return 0;
 }
+static inline int of_irq_get(struct device_node *dev, int index)
+{
+	return 0;
+}
 #endif
 
 #if defined(CONFIG_OF)

Signature · 1 line

1.9.1

Tony Lindgren

Tested-by on v1 2/2

2014-04-23 23:42 UTC #3 lore raw

Re: [PATCH 2/2] of/irq: do irq resolution in platform_get_irq

Quoted 29 lines · Rob Herring

From: Rob Herring <[email protected]>
Currently we get the following kind of errors if we try to use interrupt phandles to irqchips that have not yet initialized:
irq: no irq domain found for /ocp/pinmux at 48002030 !
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at drivers/of/platform.c:171 of_device_alloc+0x144/0x184()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.12.0-00038-g42a9708 #1012
(show_stack+0x14/0x1c)
(dump_stack+0x6c/0xa0)
(warn_slowpath_common+0x64/0x84)
(warn_slowpath_null+0x1c/0x24)
(of_device_alloc+0x144/0x184)
(of_platform_device_create_pdata+0x44/0x9c)
(of_platform_bus_create+0xd0/0x170)
(of_platform_bus_create+0x12c/0x170)
(of_platform_populate+0x60/0x98)
This is because we're wrongly trying to populate resources that are not yet available. It's perfectly valid to create irqchips dynamically, so let's fix up the issue by resolving the interrupt resources when platform_get_irq is called.
And then we also need to accept the fact that some irqdomains do not exist that early on, and only get initialized later on. So we can make the current WARN_ON into just into a pr_debug().

Quoted 7 lines

We still attempt to populate irq resources when we create the devices. This allows current drivers which don't use platform_get_irq to continue to function. Once all drivers are fixed, this code can be removed.
Suggested-by Russell King <[email protected]>
Signed-off-by Rob Herring <[email protected]>
Signed-off-by Tony Lindgren <[email protected]>

Great, works for me. Hopefully this patch is non-intrusive enough for people for the -rc cycle too?

Tested-by Tony Lindgren <[email protected]>

Quoted 119 lines

---
 drivers/base/platform.c |  7 ++++++-
 drivers/of/irq.c        | 26 ++++++++++++++++++++++++++
 drivers/of/platform.c   |  4 +++-
 include/linux/of_irq.h  |  7 ++++++-
 4 files changed, 41 insertions(+), 3 deletions(-)

drivers/base/platform.c +6 -1

index e714709..5b47210 100644
@@ -13,6 +13,7 @@
 #include <linux/string.h>
 #include <linux/platform_device.h>
 #include <linux/of_device.h>
+#include <linux/of_irq.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/dma-mapping.h>

@@ -87,7 +88,11 @@ int platform_get_irq(struct platform_device *dev, unsigned int num)
 		return -ENXIO;
 	return dev->archdata.irqs[num];
 #else
-	struct resource *r = platform_get_resource(dev, IORESOURCE_IRQ, num);
+	struct resource *r;
+	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node)
+		return of_irq_get(dev->dev.of_node, num);
+
+	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
 
 	return r ? r->start : -ENXIO;
 #endif

drivers/of/irq.c +26 -0

index 9bcf2cf..ca01893 100644
@@ -380,6 +380,32 @@ int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
 EXPORT_SYMBOL_GPL(of_irq_to_resource);
 
 /**
+ * of_irq_get - Decode a node's IRQ and return it as a Linux irq number
+ * @dev: pointer to device tree node
+ * @index: zero-based index of the irq
+ *
+ * Returns Linux irq number on success, or -EPROBE_DEFER if the irq domain
+ * is not yet created.
+ *
+ */
+int of_irq_get(struct device_node *dev, int index)
+{
+	int rc;
+	struct of_phandle_args oirq;
+	struct irq_domain *domain;
+
+	rc = of_irq_parse_one(dev, index, &oirq);
+	if (rc)
+		return rc;
+
+	domain = irq_find_host(oirq.np);
+	if (!domain)
+		return -EPROBE_DEFER;
+
+	return irq_create_of_mapping(&oirq);
+}
+
+/**
  * of_irq_count - Count the number of IRQs a node uses
  * @dev: pointer to device tree node
  */

drivers/of/platform.c +3 -1

index 404d1da..bd47fbc 100644
@@ -168,7 +168,9 @@ struct platform_device *of_device_alloc(struct device_node *np,
 			rc = of_address_to_resource(np, i, res);
 			WARN_ON(rc);
 		}
-		WARN_ON(of_irq_to_resource_table(np, res, num_irq) != num_irq);
+		if (of_irq_to_resource_table(np, res, num_irq) != num_irq)
+			pr_debug("not all legacy IRQ resources mapped for %s\n",
+				 np->name);
 	}
 
 	dev->dev.of_node = of_node_get(np);

include/linux/of_irq.h +6 -1

index 3f23b44..bc9e51a 100644
@@ -34,21 +34,26 @@ static inline int of_irq_parse_oldworld(struct device_node *device, int index,
 extern int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq);
 extern int of_irq_parse_one(struct device_node *device, int index,
 			  struct of_phandle_args *out_irq);
-extern unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data);
 extern int of_irq_to_resource(struct device_node *dev, int index,
 			      struct resource *r);
 extern int of_irq_to_resource_table(struct device_node *dev,
 		struct resource *res, int nr_irqs);
+extern unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data);
 
 extern void of_irq_init(const struct of_device_id *matches);
 
 #ifdef CONFIG_OF_IRQ
 extern int of_irq_count(struct device_node *dev);
+extern int of_irq_get(struct device_node *dev, int index);
 #else
 static inline int of_irq_count(struct device_node *dev)
 {
 	return 0;
 }
+static inline int of_irq_get(struct device_node *dev, int index)
+{
+	return 0;
+}
 #endif
 
 #if defined(CONFIG_OF)

Signature · 1 line

1.9.1

Grant Likely

2014-04-24 16:10 UTC #4 lore raw

Re: [PATCH 2/2] of/irq: do irq resolution in platform_get_irq

Quoted 34 lines · Tony Lindgren

Quoted 33 lines · Rob Herring
From: Rob Herring <[email protected]>
Currently we get the following kind of errors if we try to use interrupt phandles to irqchips that have not yet initialized:
irq: no irq domain found for /ocp/pinmux at 48002030 !
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at drivers/of/platform.c:171 of_device_alloc+0x144/0x184()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.12.0-00038-g42a9708 #1012
(show_stack+0x14/0x1c)
(dump_stack+0x6c/0xa0)
(warn_slowpath_common+0x64/0x84)
(warn_slowpath_null+0x1c/0x24)
(of_device_alloc+0x144/0x184)
(of_platform_device_create_pdata+0x44/0x9c)
(of_platform_bus_create+0xd0/0x170)
(of_platform_bus_create+0x12c/0x170)
(of_platform_populate+0x60/0x98)
This is because we're wrongly trying to populate resources that are not yet available. It's perfectly valid to create irqchips dynamically, so let's fix up the issue by resolving the interrupt resources when platform_get_irq is called.
And then we also need to accept the fact that some irqdomains do not exist that early on, and only get initialized later on. So we can make the current WARN_ON into just into a pr_debug().
We still attempt to populate irq resources when we create the devices. This allows current drivers which don't use platform_get_irq to continue to function. Once all drivers are fixed, this code can be removed.

Quoted 6 lines

Quoted 3 lines
Suggested-by Russell King <[email protected]>
Signed-off-by Rob Herring <[email protected]>
Signed-off-by Tony Lindgren <[email protected]>
Great, works for me. Hopefully this patch is non-intrusive enough for people for the -rc cycle too?

Both patches look good. I've put them in my tree and will push it out shortly. I want to make sure there are no regressions on PowerPC, so I'll give it a few days in linux-next before asking Linus to pull.

Tony, how far back does this need to be backported?

Tony Lindgren

2014-04-24 17:19 UTC #5 lore raw

Re: [PATCH 2/2] of/irq: do irq resolution in platform_get_irq

Quoted 39 lines · Grant Likely

Quoted 38 lines · Tony Lindgren
Quoted 36 lines · Rob Herring
From: Rob Herring <[email protected]>
Currently we get the following kind of errors if we try to use interrupt phandles to irqchips that have not yet initialized:
irq: no irq domain found for /ocp/pinmux at 48002030 !
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at drivers/of/platform.c:171 of_device_alloc+0x144/0x184()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.12.0-00038-g42a9708 #1012
(show_stack+0x14/0x1c)
(dump_stack+0x6c/0xa0)
(warn_slowpath_common+0x64/0x84)
(warn_slowpath_null+0x1c/0x24)
(of_device_alloc+0x144/0x184)
(of_platform_device_create_pdata+0x44/0x9c)
(of_platform_bus_create+0xd0/0x170)
(of_platform_bus_create+0x12c/0x170)
(of_platform_populate+0x60/0x98)
This is because we're wrongly trying to populate resources that are not yet available. It's perfectly valid to create irqchips dynamically, so let's fix up the issue by resolving the interrupt resources when platform_get_irq is called.
And then we also need to accept the fact that some irqdomains do not exist that early on, and only get initialized later on. So we can make the current WARN_ON into just into a pr_debug().
We still attempt to populate irq resources when we create the devices. This allows current drivers which don't use platform_get_irq to continue to function. Once all drivers are fixed, this code can be removed.
Suggested-by Russell King <[email protected]>
Signed-off-by Rob Herring <[email protected]>
Signed-off-by Tony Lindgren <[email protected]>

Quoted 6 lines

Quoted 2 lines
Great, works for me. Hopefully this patch is non-intrusive enough for people for the -rc cycle too?
Both patches look good. I've put them in my tree and will push it out shortly. I want to make sure there are no regressions on PowerPC, so I'll give it a few days in linux-next before asking Linus to pull.

Great, sounds good to me.

Quoted 1 line

Tony, how far back does this need to be backported?

The issue seems to have been around ever since the start of DT with platform_bus, and people have been probably working around it with the initcall levels and using irq_of_parse_and_map instead of platform_get_irq.

I noticed the issue last year around the time interrupts-extended binding patches were posted and I was adding the irqdomain support to pinctrl-single.c for wake-up interrupts.

So the fix should probably go back to at least v3.12 or v3.10 as those are recent longterm kernels. The patch seems to apply to both of them with fuzz except for include/linux/of_irq.h.

Sligthly related to this patch, also 4a43d686fe33 (of/irq: Pass trigger type in IRQ resource flags) should also get tagged stable too if not done already as that keeps some legacy drivers working.

Regards,

Tony

Thierry Reding

2014-04-24 18:42 UTC #6 lore raw

Re: [PATCH 2/2] of/irq: do irq resolution in platform_get_irq

In reply to Rob Herring

Quoted 36 lines · Rob Herring

From: Rob Herring <[email protected]>
Currently we get the following kind of errors if we try to use interrupt phandles to irqchips that have not yet initialized:
irq: no irq domain found for /ocp/pinmux at 48002030 !
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at drivers/of/platform.c:171 of_device_alloc+0x144/0x184()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.12.0-00038-g42a9708 #1012
(show_stack+0x14/0x1c)
(dump_stack+0x6c/0xa0)
(warn_slowpath_common+0x64/0x84)
(warn_slowpath_null+0x1c/0x24)
(of_device_alloc+0x144/0x184)
(of_platform_device_create_pdata+0x44/0x9c)
(of_platform_bus_create+0xd0/0x170)
(of_platform_bus_create+0x12c/0x170)
(of_platform_populate+0x60/0x98)
This is because we're wrongly trying to populate resources that are not yet available. It's perfectly valid to create irqchips dynamically, so let's fix up the issue by resolving the interrupt resources when platform_get_irq is called.
And then we also need to accept the fact that some irqdomains do not exist that early on, and only get initialized later on. So we can make the current WARN_ON into just into a pr_debug().
We still attempt to populate irq resources when we create the devices. This allows current drivers which don't use platform_get_irq to continue to function. Once all drivers are fixed, this code can be removed.
Suggested-by Russell King <[email protected]>
Signed-off-by Rob Herring <[email protected]>
Signed-off-by Tony Lindgren <[email protected]>

Quoted 6 lines

---
 drivers/base/platform.c |  7 ++++++-
 drivers/of/irq.c        | 26 ++++++++++++++++++++++++++
 drivers/of/platform.c   |  4 +++-
 include/linux/of_irq.h  |  7 ++++++-
 4 files changed, 41 insertions(+), 3 deletions(-)

Hehe... that's largely what we already had back in January[0]. Glad to see that people could finally agree on what to do about this.

Thierry

[0]: https://lkml.org/lkml/2014/1/8/240
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Grant Likely

2014-04-24 20:47 UTC #7 lore raw

Re: [PATCH 2/2] of/irq: do irq resolution in platform_get_irq

Quoted 44 lines · Thierry Reding

Quoted 36 lines · Rob Herring
From: Rob Herring <[email protected]>
Currently we get the following kind of errors if we try to use interrupt phandles to irqchips that have not yet initialized:
irq: no irq domain found for /ocp/pinmux at 48002030 !
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at drivers/of/platform.c:171 of_device_alloc+0x144/0x184()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.12.0-00038-g42a9708 #1012
(show_stack+0x14/0x1c)
(dump_stack+0x6c/0xa0)
(warn_slowpath_common+0x64/0x84)
(warn_slowpath_null+0x1c/0x24)
(of_device_alloc+0x144/0x184)
(of_platform_device_create_pdata+0x44/0x9c)
(of_platform_bus_create+0xd0/0x170)
(of_platform_bus_create+0x12c/0x170)
(of_platform_populate+0x60/0x98)
This is because we're wrongly trying to populate resources that are not yet available. It's perfectly valid to create irqchips dynamically, so let's fix up the issue by resolving the interrupt resources when platform_get_irq is called.
And then we also need to accept the fact that some irqdomains do not exist that early on, and only get initialized later on. So we can make the current WARN_ON into just into a pr_debug().
We still attempt to populate irq resources when we create the devices. This allows current drivers which don't use platform_get_irq to continue to function. Once all drivers are fixed, this code can be removed.
Suggested-by Russell King <[email protected]>
Signed-off-by Rob Herring <[email protected]>
Signed-off-by Tony Lindgren <[email protected]>
Quoted 6 lines
---
 drivers/base/platform.c |  7 ++++++-
 drivers/of/irq.c        | 26 ++++++++++++++++++++++++++
 drivers/of/platform.c   |  4 +++-
 include/linux/of_irq.h  |  7 ++++++-
 4 files changed, 41 insertions(+), 3 deletions(-)

Quoted 6 lines

Hehe... that's largely what we already had back in January[0]. Glad to see that people could finally agree on what to do about this.
Thierry
[0]: https://lkml.org/lkml/2014/1/8/240

Sometimes it takes prodding around with the other options to figure out an earlier approach was on the right track. I'm very happy to finally have a solution here that appears to be working.

I've pushed it out to my tree so it gets into linux-next. Please test before I ask Linus to pull.

git://git.secretlab.ca/git/linux devicetree/merge

Tony Lindgren

2014-04-23 23:43 UTC #8 lore raw

In reply to Rob Herring

Quoted 10 lines · Rob Herring

From: Rob Herring <[email protected]>
This is atleast the 4th attempt to fix a long standing issue with DT irq resolution needing to support deferred probe when irq parent is not yet initialized. This version implements Russell King's suggestion to do irq resolution when platform_get_irq is called.
Tony, I squashed your warning fix (dropping the other part) and stole much of your commit message. Let me know if you have any issues with that.

Nope, looks good, just gave it a try and it fixes the problem for me.

Regards,

Tony

Quoted 15 lines

Rob Herring (2):
of: selftest: add deferred probe interrupt test
of/irq: do irq resolution in platform_get_irq

 drivers/base/platform.c                        |  7 +++++-
 drivers/of/irq.c                               | 26 +++++++++++++++++++++
 drivers/of/platform.c                          |  4 +++-
 drivers/of/selftest.c                          | 32 ++++++++++++++++++++++++++
 drivers/of/testcase-data/tests-interrupts.dtsi | 12 ++++++++++
 include/linux/of_irq.h                         |  7 +++++-
 6 files changed, 85 insertions(+), 3 deletions(-)

Signature · 1 line

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