Patchwork powerpc/pseries: Make request_ras_irqs() available to other pseries code

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Submitter Mark Nelson
Date May 17, 2010, 12:33 p.m.
Message ID <201005172233.01183.markn@au1.ibm.com>
Download mbox | patch
Permalink /patch/52791/
State Superseded
Headers show

Comments

Mark Nelson - May 17, 2010, 12:33 p.m.
At the moment only the RAS code uses event-sources interrupts (for EPOW
events and internal errors) so request_ras_irqs() (which actually requests
the event-sources interrupts) is found in ras.c and is static.

We want to be able to use event-sources interrupts in other pseries code,
so let's rename request_ras_irqs() to request_event_sources_irqs() and
move it to event_sources.c.

This will be used in an upcoming patch that adds support for IO Event
interrupts that come through as event sources.

Signed-off-by: Mark Nelson <markn@au1.ibm.com>
---
 arch/powerpc/platforms/pseries/Makefile        |    2 
 arch/powerpc/platforms/pseries/event_sources.c |   79 +++++++++++++++++++++++++
 arch/powerpc/platforms/pseries/event_sources.h |   29 +++++++++
 arch/powerpc/platforms/pseries/ras.c           |   63 +------------------
 4 files changed, 113 insertions(+), 60 deletions(-)
Michael Ellerman - May 18, 2010, 12:40 p.m.
On Mon, 2010-05-17 at 22:33 +1000, Mark Nelson wrote:
> At the moment only the RAS code uses event-sources interrupts (for EPOW
> events and internal errors) so request_ras_irqs() (which actually requests
> the event-sources interrupts) is found in ras.c and is static.

Hi Mark,

Just a few niggles,

...

> +
> +void request_event_sources_irqs(struct device_node *np,
> +				irq_handler_t handler,
> +				const char *name)
> +{
> +	int i, index, count = 0;
> +	struct of_irq oirq;
> +	const u32 *opicprop;
> +	unsigned int opicplen;
> +	unsigned int virqs[16];
> +
> +	/* Check for obsolete "open-pic-interrupt" property. If present, then
> +	 * map those interrupts using the default interrupt host and default
> +	 * trigger
> +	 */
> +	opicprop = of_get_property(np, "open-pic-interrupt", &opicplen);
> +	if (opicprop) {
> +		opicplen /= sizeof(u32);
> +		for (i = 0; i < opicplen; i++) {
> +			if (count > 15)
> +				break;
> +			virqs[count] = irq_create_mapping(NULL, *(opicprop++));
> +			if (virqs[count] == NO_IRQ)
> +				printk(KERN_ERR "Unable to allocate interrupt "
> +				       "number for %s\n", np->full_name);
> +			else
> +				count++;
> +
> +		}
> +	}
> +	/* Else use normal interrupt tree parsing */
> +	else {
> +		/* First try to do a proper OF tree parsing */
> +		for (index = 0; of_irq_map_one(np, index, &oirq) == 0;
> +		     index++) {
> +			if (count > 15)
> +				break;
> +			virqs[count] = irq_create_of_mapping(oirq.controller,
> +							    oirq.specifier,
> +							    oirq.size);
> +			if (virqs[count] == NO_IRQ)
> +				printk(KERN_ERR "Unable to allocate interrupt "
> +				       "number for %s\n", np->full_name);
> +			else
> +				count++;
> +		}
> +	}
> +
> +	/* Now request them */
> +	for (i = 0; i < count; i++) {
> +		if (request_irq(virqs[i], handler, 0, name, NULL)) {
> +			printk(KERN_ERR "Unable to request interrupt %d for "
> +			       "%s\n", virqs[i], np->full_name);
> +			return;
> +		}
> +	}

Existing code I know, but the error handling in here is a little lax,
what's not going to work if we miss some or all of the interrupts?

> Index: upstream/arch/powerpc/platforms/pseries/event_sources.h
> ===================================================================
> --- /dev/null
> +++ upstream/arch/powerpc/platforms/pseries/event_sources.h
> @@ -0,0 +1,29 @@
> +/*
> + * Copyright (C) 2001 Dave Engebretsen IBM Corporation
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
> + */
> +
> +#ifndef _POWERPC_EVENT_SOURCES_H
> +#define _POWERPC_EVENT_SOURCES_H
> +
> +#include <linux/interrupt.h>
> +
> +struct device_node;
> +
> +extern void request_event_sources_irqs(struct device_node *np,
> +				       irq_handler_t handler, const char *name);

This could just go in platforms/pseries/pseries.h

> Index: upstream/arch/powerpc/platforms/pseries/ras.c
> ===================================================================
> --- upstream.orig/arch/powerpc/platforms/pseries/ras.c
> +++ upstream/arch/powerpc/platforms/pseries/ras.c
> @@ -50,6 +50,7 @@
>  #include <asm/firmware.h>
>  
>  #include "pseries.h"
> +#include "event_sources.h"

:)


cheers
Mark Nelson - May 19, 2010, 6:35 a.m.
Hi Michael,

Thanks for looking over these patches!

On Tuesday 18 May 2010 22:40:51 Michael Ellerman wrote:
> On Mon, 2010-05-17 at 22:33 +1000, Mark Nelson wrote:
> > At the moment only the RAS code uses event-sources interrupts (for EPOW
> > events and internal errors) so request_ras_irqs() (which actually requests
> > the event-sources interrupts) is found in ras.c and is static.
> 
> Hi Mark,
> 
> Just a few niggles,
> 
> ...
> 
> > +
> > +void request_event_sources_irqs(struct device_node *np,
> > +				irq_handler_t handler,
> > +				const char *name)
> > +{
> > +	int i, index, count = 0;
> > +	struct of_irq oirq;
> > +	const u32 *opicprop;
> > +	unsigned int opicplen;
> > +	unsigned int virqs[16];
> > +
> > +	/* Check for obsolete "open-pic-interrupt" property. If present, then
> > +	 * map those interrupts using the default interrupt host and default
> > +	 * trigger
> > +	 */
> > +	opicprop = of_get_property(np, "open-pic-interrupt", &opicplen);
> > +	if (opicprop) {
> > +		opicplen /= sizeof(u32);
> > +		for (i = 0; i < opicplen; i++) {
> > +			if (count > 15)
> > +				break;
> > +			virqs[count] = irq_create_mapping(NULL, *(opicprop++));
> > +			if (virqs[count] == NO_IRQ)
> > +				printk(KERN_ERR "Unable to allocate interrupt "
> > +				       "number for %s\n", np->full_name);
> > +			else
> > +				count++;
> > +
> > +		}
> > +	}
> > +	/* Else use normal interrupt tree parsing */
> > +	else {
> > +		/* First try to do a proper OF tree parsing */
> > +		for (index = 0; of_irq_map_one(np, index, &oirq) == 0;
> > +		     index++) {
> > +			if (count > 15)
> > +				break;
> > +			virqs[count] = irq_create_of_mapping(oirq.controller,
> > +							    oirq.specifier,
> > +							    oirq.size);
> > +			if (virqs[count] == NO_IRQ)
> > +				printk(KERN_ERR "Unable to allocate interrupt "
> > +				       "number for %s\n", np->full_name);
> > +			else
> > +				count++;
> > +		}
> > +	}
> > +
> > +	/* Now request them */
> > +	for (i = 0; i < count; i++) {
> > +		if (request_irq(virqs[i], handler, 0, name, NULL)) {
> > +			printk(KERN_ERR "Unable to request interrupt %d for "
> > +			       "%s\n", virqs[i], np->full_name);
> > +			return;
> > +		}
> > +	}
> 
> Existing code I know, but the error handling in here is a little lax,
> what's not going to work if we miss some or all of the interrupts?

That's a good point. For the existing code, if we miss an EPOW event
it just means that the event won't be logged (as that's all we do with
those events at the moment, although there is a comment saying
that it should be fixed to take appropriate action depending upon the
type of power failure); but it's a bigger problem if we miss one of the
RAS errors because then we could miss a fatal event that we should halt
the machine on. And for the upcoming IO events it's even worse as we'd
miss an interrupt from the device...

I would do it in a follow-on patch rather than this one, but what would
be a good course of action if we can't request the interrupt?

> 
> > Index: upstream/arch/powerpc/platforms/pseries/event_sources.h
> > ===================================================================
> > --- /dev/null
> > +++ upstream/arch/powerpc/platforms/pseries/event_sources.h
> > @@ -0,0 +1,29 @@
> > +/*
> > + * Copyright (C) 2001 Dave Engebretsen IBM Corporation
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License as published by
> > + * the Free Software Foundation; either version 2 of the License, or
> > + * (at your option) any later version.
> > + *
> > + * This program is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> > + * GNU General Public License for more details.
> > + *
> > + * You should have received a copy of the GNU General Public License
> > + * along with this program; if not, write to the Free Software
> > + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
> > + */
> > +
> > +#ifndef _POWERPC_EVENT_SOURCES_H
> > +#define _POWERPC_EVENT_SOURCES_H
> > +
> > +#include <linux/interrupt.h>
> > +
> > +struct device_node;
> > +
> > +extern void request_event_sources_irqs(struct device_node *np,
> > +				       irq_handler_t handler, const char *name);
> 
> This could just go in platforms/pseries/pseries.h

That's true - it is only one function. I'll move it.

> 
> > Index: upstream/arch/powerpc/platforms/pseries/ras.c
> > ===================================================================
> > --- upstream.orig/arch/powerpc/platforms/pseries/ras.c
> > +++ upstream/arch/powerpc/platforms/pseries/ras.c
> > @@ -50,6 +50,7 @@
> >  #include <asm/firmware.h>
> >  
> >  #include "pseries.h"
> > +#include "event_sources.h"
> 
> :)
> 

Thanks!
Mark
Michael Ellerman - May 19, 2010, 6:35 a.m.
On Wed, 2010-05-19 at 16:35 +1000, Mark Nelson wrote:
> Hi Michael,
> 
> Thanks for looking over these patches!
..
> > 
> > Existing code I know, but the error handling in here is a little lax,
> > what's not going to work if we miss some or all of the interrupts?
> 
> That's a good point. For the existing code, if we miss an EPOW event
> it just means that the event won't be logged (as that's all we do with
> those events at the moment, although there is a comment saying
> that it should be fixed to take appropriate action depending upon the
> type of power failure); but it's a bigger problem if we miss one of the
> RAS errors because then we could miss a fatal event that we should halt
> the machine on. And for the upcoming IO events it's even worse as we'd
> miss an interrupt from the device...

Yeah that's what I was thinking.

> I would do it in a follow-on patch rather than this one, but what would
> be a good course of action if we can't request the interrupt?

Yes a follow on patch is the way to do it.

There shouldn't be that many reasons the request fails, other than
ENOMEM, or broken device tree perhaps. It's definitely worth a
WARN_ON(), people notice those at least.

cheers
Mark Nelson - May 19, 2010, 6:54 a.m.
On Wednesday 19 May 2010 16:35:54 Michael Ellerman wrote:
> On Wed, 2010-05-19 at 16:35 +1000, Mark Nelson wrote:
> > Hi Michael,
> > 
> > Thanks for looking over these patches!
> ..
> > > 
> > > Existing code I know, but the error handling in here is a little lax,
> > > what's not going to work if we miss some or all of the interrupts?
> > 
> > That's a good point. For the existing code, if we miss an EPOW event
> > it just means that the event won't be logged (as that's all we do with
> > those events at the moment, although there is a comment saying
> > that it should be fixed to take appropriate action depending upon the
> > type of power failure); but it's a bigger problem if we miss one of the
> > RAS errors because then we could miss a fatal event that we should halt
> > the machine on. And for the upcoming IO events it's even worse as we'd
> > miss an interrupt from the device...
> 
> Yeah that's what I was thinking.
> 
> > I would do it in a follow-on patch rather than this one, but what would
> > be a good course of action if we can't request the interrupt?
> 
> Yes a follow on patch is the way to do it.
> 
> There shouldn't be that many reasons the request fails, other than
> ENOMEM, or broken device tree perhaps. It's definitely worth a
> WARN_ON(), people notice those at least.

That sounds good. I'll do a simple follow-on patch that adds the
WARN_ON().

Thanks!
Mark

Patch

Index: upstream/arch/powerpc/platforms/pseries/event_sources.c
===================================================================
--- /dev/null
+++ upstream/arch/powerpc/platforms/pseries/event_sources.c
@@ -0,0 +1,79 @@ 
+/*
+ * Copyright (C) 2001 Dave Engebretsen IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include <asm/prom.h>
+
+#include "event_sources.h"
+
+void request_event_sources_irqs(struct device_node *np,
+				irq_handler_t handler,
+				const char *name)
+{
+	int i, index, count = 0;
+	struct of_irq oirq;
+	const u32 *opicprop;
+	unsigned int opicplen;
+	unsigned int virqs[16];
+
+	/* Check for obsolete "open-pic-interrupt" property. If present, then
+	 * map those interrupts using the default interrupt host and default
+	 * trigger
+	 */
+	opicprop = of_get_property(np, "open-pic-interrupt", &opicplen);
+	if (opicprop) {
+		opicplen /= sizeof(u32);
+		for (i = 0; i < opicplen; i++) {
+			if (count > 15)
+				break;
+			virqs[count] = irq_create_mapping(NULL, *(opicprop++));
+			if (virqs[count] == NO_IRQ)
+				printk(KERN_ERR "Unable to allocate interrupt "
+				       "number for %s\n", np->full_name);
+			else
+				count++;
+
+		}
+	}
+	/* Else use normal interrupt tree parsing */
+	else {
+		/* First try to do a proper OF tree parsing */
+		for (index = 0; of_irq_map_one(np, index, &oirq) == 0;
+		     index++) {
+			if (count > 15)
+				break;
+			virqs[count] = irq_create_of_mapping(oirq.controller,
+							    oirq.specifier,
+							    oirq.size);
+			if (virqs[count] == NO_IRQ)
+				printk(KERN_ERR "Unable to allocate interrupt "
+				       "number for %s\n", np->full_name);
+			else
+				count++;
+		}
+	}
+
+	/* Now request them */
+	for (i = 0; i < count; i++) {
+		if (request_irq(virqs[i], handler, 0, name, NULL)) {
+			printk(KERN_ERR "Unable to request interrupt %d for "
+			       "%s\n", virqs[i], np->full_name);
+			return;
+		}
+	}
+}
+
Index: upstream/arch/powerpc/platforms/pseries/event_sources.h
===================================================================
--- /dev/null
+++ upstream/arch/powerpc/platforms/pseries/event_sources.h
@@ -0,0 +1,29 @@ 
+/*
+ * Copyright (C) 2001 Dave Engebretsen IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#ifndef _POWERPC_EVENT_SOURCES_H
+#define _POWERPC_EVENT_SOURCES_H
+
+#include <linux/interrupt.h>
+
+struct device_node;
+
+extern void request_event_sources_irqs(struct device_node *np,
+				       irq_handler_t handler, const char *name);
+
+#endif /* _POWERPC_EVENT_SOURCES_H */
Index: upstream/arch/powerpc/platforms/pseries/Makefile
===================================================================
--- upstream.orig/arch/powerpc/platforms/pseries/Makefile
+++ upstream/arch/powerpc/platforms/pseries/Makefile
@@ -7,7 +7,7 @@  EXTRA_CFLAGS		+= -DDEBUG
 endif
 
 obj-y			:= lpar.o hvCall.o nvram.o reconfig.o \
-			   setup.o iommu.o ras.o \
+			   setup.o iommu.o event_sources.o ras.o \
 			   firmware.o power.o dlpar.o
 obj-$(CONFIG_SMP)	+= smp.o
 obj-$(CONFIG_XICS)	+= xics.o
Index: upstream/arch/powerpc/platforms/pseries/ras.c
===================================================================
--- upstream.orig/arch/powerpc/platforms/pseries/ras.c
+++ upstream/arch/powerpc/platforms/pseries/ras.c
@@ -50,6 +50,7 @@ 
 #include <asm/firmware.h>
 
 #include "pseries.h"
+#include "event_sources.h"
 
 static unsigned char ras_log_buf[RTAS_ERROR_LOG_MAX];
 static DEFINE_SPINLOCK(ras_log_buf_lock);
@@ -67,63 +68,6 @@  static irqreturn_t ras_epow_interrupt(in
 static irqreturn_t ras_error_interrupt(int irq, void *dev_id);
 
 
-static void request_ras_irqs(struct device_node *np,
-			irq_handler_t handler,
-			const char *name)
-{
-	int i, index, count = 0;
-	struct of_irq oirq;
-	const u32 *opicprop;
-	unsigned int opicplen;
-	unsigned int virqs[16];
-
-	/* Check for obsolete "open-pic-interrupt" property. If present, then
-	 * map those interrupts using the default interrupt host and default
-	 * trigger
-	 */
-	opicprop = of_get_property(np, "open-pic-interrupt", &opicplen);
-	if (opicprop) {
-		opicplen /= sizeof(u32);
-		for (i = 0; i < opicplen; i++) {
-			if (count > 15)
-				break;
-			virqs[count] = irq_create_mapping(NULL, *(opicprop++));
-			if (virqs[count] == NO_IRQ)
-				printk(KERN_ERR "Unable to allocate interrupt "
-				       "number for %s\n", np->full_name);
-			else
-				count++;
-
-		}
-	}
-	/* Else use normal interrupt tree parsing */
-	else {
-		/* First try to do a proper OF tree parsing */
-		for (index = 0; of_irq_map_one(np, index, &oirq) == 0;
-		     index++) {
-			if (count > 15)
-				break;
-			virqs[count] = irq_create_of_mapping(oirq.controller,
-							    oirq.specifier,
-							    oirq.size);
-			if (virqs[count] == NO_IRQ)
-				printk(KERN_ERR "Unable to allocate interrupt "
-				       "number for %s\n", np->full_name);
-			else
-				count++;
-		}
-	}
-
-	/* Now request them */
-	for (i = 0; i < count; i++) {
-		if (request_irq(virqs[i], handler, 0, name, NULL)) {
-			printk(KERN_ERR "Unable to request interrupt %d for "
-			       "%s\n", virqs[i], np->full_name);
-			return;
-		}
-	}
-}
-
 /*
  * Initialize handlers for the set of interrupts caused by hardware errors
  * and power system events.
@@ -138,14 +82,15 @@  static int __init init_ras_IRQ(void)
 	/* Internal Errors */
 	np = of_find_node_by_path("/event-sources/internal-errors");
 	if (np != NULL) {
-		request_ras_irqs(np, ras_error_interrupt, "RAS_ERROR");
+		request_event_sources_irqs(np, ras_error_interrupt,
+					   "RAS_ERROR");
 		of_node_put(np);
 	}
 
 	/* EPOW Events */
 	np = of_find_node_by_path("/event-sources/epow-events");
 	if (np != NULL) {
-		request_ras_irqs(np, ras_epow_interrupt, "RAS_EPOW");
+		request_event_sources_irqs(np, ras_epow_interrupt, "RAS_EPOW");
 		of_node_put(np);
 	}