Re: [PATCH] powerpc: pseries: use irq_of_parse_and_map helper

From: Michael Ellerman
Date: Tue Jan 23 2018 - 01:54:00 EST


Rob Herring <robh@xxxxxxxxxx> writes:

> Instead of calling both of_irq_parse_one and irq_create_of_mapping, call
> of_irq_parse_and_map instead which does the same thing. This gets us closer
> to making the former 2 functions static.
>
> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
> Cc: Paul Mackerras <paulus@xxxxxxxxx>
> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
> Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
> ---
> arch/powerpc/platforms/pseries/event_sources.c | 11 ++++-------
> 1 file changed, 4 insertions(+), 7 deletions(-)

Sorry NAK, this doesn't boot.

> diff --git a/arch/powerpc/platforms/pseries/event_sources.c b/arch/powerpc/platforms/pseries/event_sources.c
> index 6eeb0d4bab61..b0d8c146fe7b 100644
> --- a/arch/powerpc/platforms/pseries/event_sources.c
> +++ b/arch/powerpc/platforms/pseries/event_sources.c
> @@ -16,7 +16,8 @@
> * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
> */
>
> -#include <asm/prom.h>
> +#include <linux/interrupt.h>
> +#include <linux/of_irq.h>
>
> #include "pseries.h"
>
> @@ -25,15 +26,11 @@ void request_event_sources_irqs(struct device_node *np,
> const char *name)
> {
> int i, index, count = 0;
> - struct of_phandle_args oirq;
> unsigned int virqs[16];
>
> /* First try to do a proper OF tree parsing */
> - for (index = 0; of_irq_parse_one(np, index, &oirq) == 0;
> - index++) {
> - if (count > 15)
> - break;
> - virqs[count] = irq_create_of_mapping(&oirq);
> + for (index = 0; count < 16; index++) {
> + virqs[count] = irq_of_parse_and_map(np, index);
> if (!virqs[count]) {
> pr_err("event-sources: Unable to allocate "
> "interrupt number for %pOF\n",

np);
WARN_ON(1);
} else {
count++;
}
}


Which is an infinite loop if we have less than 16 irqs, and spews the
warning continuously.

Are you trying to remove the low-level routines or is this just a
cleanup?

The patch below works, it loses the error handling if the interrupts
property is corrupt/empty, but that's probably overly paranoid anyway.

cheers

diff --git a/arch/powerpc/platforms/pseries/event_sources.c b/arch/powerpc/platforms/pseries/event_sources.c
index 6eeb0d4bab61..25c38077c894 100644
--- a/arch/powerpc/platforms/pseries/event_sources.c
+++ b/arch/powerpc/platforms/pseries/event_sources.c
@@ -16,7 +16,8 @@
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/

-#include <asm/prom.h>
+#include <linux/interrupt.h>
+#include <linux/of_irq.h>

#include "pseries.h"

@@ -24,34 +25,16 @@ void request_event_sources_irqs(struct device_node *np,
irq_handler_t handler,
const char *name)
{
- int i, index, count = 0;
- struct of_phandle_args oirq;
- unsigned int virqs[16];
+ unsigned int virq;
+ int i, rc;

- /* First try to do a proper OF tree parsing */
- for (index = 0; of_irq_parse_one(np, index, &oirq) == 0;
- index++) {
- if (count > 15)
+ for (i = 0; i < 16; i++) {
+ virq = irq_of_parse_and_map(np, i);
+ if (!virq)
break;
- virqs[count] = irq_create_of_mapping(&oirq);
- if (!virqs[count]) {
- pr_err("event-sources: Unable to allocate "
- "interrupt number for %pOF\n",
- np);
- WARN_ON(1);
- } else {
- count++;
- }
- }

- /* Now request them */
- for (i = 0; i < count; i++) {
- if (request_irq(virqs[i], handler, 0, name, NULL)) {
- pr_err("event-sources: Unable to request interrupt "
- "%d for %pOF\n", virqs[i], np);
- WARN_ON(1);
- return;
- }
+ rc = request_irq(virq, handler, 0, name, NULL);
+ WARN(rc, "event-sources: Unable to request interrupt %d for %pOF\n",
+ virq, np);
}
}
-