diff mbox series

[1/2] iommu/arm-smmu: Use platform_irq_count() to get the interrupt count

Message ID 20211223130046.9365-2-prabhakar.mahadev-lad.rj@bp.renesas.com (mailing list archive)
State New, archived
Headers show
Series iommu/arm-smmu: Use platform_irq_count() | expand

Commit Message

Lad Prabhakar Dec. 23, 2021, 1 p.m. UTC
platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
allocation of IRQ resources in DT core code, this causes an issue
when using hierarchical interrupt domains using "interrupts" property
in the node as this bypasses the hierarchical setup and messes up the
irq chaining.

In preparation for removal of static setup of IRQ resource from DT core
code use platform_get_irq_count().

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
 drivers/iommu/arm/arm-smmu/arm-smmu.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

Comments

Robin Murphy Dec. 23, 2021, 2:14 p.m. UTC | #1
On 2021-12-23 13:00, Lad Prabhakar wrote:
> platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
> allocation of IRQ resources in DT core code, this causes an issue
> when using hierarchical interrupt domains using "interrupts" property
> in the node as this bypasses the hierarchical setup and messes up the
> irq chaining.
> 
> In preparation for removal of static setup of IRQ resource from DT core
> code use platform_get_irq_count().

Nit: platform_irq_count()

> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> ---
>   drivers/iommu/arm/arm-smmu/arm-smmu.c | 12 ++++++------
>   1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> index 4bc75c4ce402..4844cd075644 100644
> --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> @@ -2105,12 +2105,12 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
>   	if (IS_ERR(smmu))
>   		return PTR_ERR(smmu);
>   
> -	num_irqs = 0;
> -	while ((res = platform_get_resource(pdev, IORESOURCE_IRQ, num_irqs))) {
> -		num_irqs++;
> -		if (num_irqs > smmu->num_global_irqs)
> -			smmu->num_context_irqs++;
> -	}
> +	num_irqs = platform_irq_count(pdev);
> +	if (num_irqs < 0)
> +		return num_irqs;
> +
> +	if (num_irqs > smmu->num_global_irqs)
> +		smmu->num_context_irqs += (num_irqs - smmu->num_global_irqs);

This seems a bit overcomplicated. I reckon:

	smmu->num_context_irqs = num_irqs - smmu->num_global_irqs;
	if (num_irqs <= smmu->num_global_irqs) {
		dev_err(...

should do it.

However, FYI I have some patches refactoring most of the IRQ stuff here 
that I plan to post next cycle (didn't quite have time to get them done 
for 5.17 as I'd hoped...), so unless this needs to go in right now as an 
urgent fix, I'm happy to take care of removing platform_get_resource() 
as part of that if it's easier.

Thanks,
Robin.

>   
>   	if (!smmu->num_context_irqs) {
>   		dev_err(dev, "found %d interrupts but expected at least %d\n",
Lad, Prabhakar Dec. 23, 2021, 5:36 p.m. UTC | #2
Hi Robin,

Thank you for the review.

On Thu, Dec 23, 2021 at 2:14 PM Robin Murphy <robin.murphy@arm.com> wrote:
>
> On 2021-12-23 13:00, Lad Prabhakar wrote:
> > platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
> > allocation of IRQ resources in DT core code, this causes an issue
> > when using hierarchical interrupt domains using "interrupts" property
> > in the node as this bypasses the hierarchical setup and messes up the
> > irq chaining.
> >
> > In preparation for removal of static setup of IRQ resource from DT core
> > code use platform_get_irq_count().
>
> Nit: platform_irq_count()
>
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > ---
> >   drivers/iommu/arm/arm-smmu/arm-smmu.c | 12 ++++++------
> >   1 file changed, 6 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> > index 4bc75c4ce402..4844cd075644 100644
> > --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
> > +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> > @@ -2105,12 +2105,12 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
> >       if (IS_ERR(smmu))
> >               return PTR_ERR(smmu);
> >
> > -     num_irqs = 0;
> > -     while ((res = platform_get_resource(pdev, IORESOURCE_IRQ, num_irqs))) {
> > -             num_irqs++;
> > -             if (num_irqs > smmu->num_global_irqs)
> > -                     smmu->num_context_irqs++;
> > -     }
> > +     num_irqs = platform_irq_count(pdev);
> > +     if (num_irqs < 0)
> > +             return num_irqs;
> > +
> > +     if (num_irqs > smmu->num_global_irqs)
> > +             smmu->num_context_irqs += (num_irqs - smmu->num_global_irqs);
>
> This seems a bit overcomplicated. I reckon:
>
>         smmu->num_context_irqs = num_irqs - smmu->num_global_irqs;
>         if (num_irqs <= smmu->num_global_irqs) {
>                 dev_err(...
>
> should do it.
>
Agreed.

> However, FYI I have some patches refactoring most of the IRQ stuff here
> that I plan to post next cycle (didn't quite have time to get them done
> for 5.17 as I'd hoped...), so unless this needs to go in right now as an
> urgent fix, I'm happy to take care of removing platform_get_resource()
> as part of that if it's easier.
>
Fine by me, let me know if it gets any later than planned I'll send a v2.

Cheers,
Prabhakar
Will Deacon Feb. 8, 2022, 3:19 p.m. UTC | #3
On Thu, Dec 23, 2021 at 02:14:35PM +0000, Robin Murphy wrote:
> On 2021-12-23 13:00, Lad Prabhakar wrote:
> > platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
> > allocation of IRQ resources in DT core code, this causes an issue
> > when using hierarchical interrupt domains using "interrupts" property
> > in the node as this bypasses the hierarchical setup and messes up the
> > irq chaining.
> > 
> > In preparation for removal of static setup of IRQ resource from DT core
> > code use platform_get_irq_count().
> 
> Nit: platform_irq_count()
> 
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > ---
> >   drivers/iommu/arm/arm-smmu/arm-smmu.c | 12 ++++++------
> >   1 file changed, 6 insertions(+), 6 deletions(-)
> > 
> > diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> > index 4bc75c4ce402..4844cd075644 100644
> > --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
> > +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> > @@ -2105,12 +2105,12 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
> >   	if (IS_ERR(smmu))
> >   		return PTR_ERR(smmu);
> > -	num_irqs = 0;
> > -	while ((res = platform_get_resource(pdev, IORESOURCE_IRQ, num_irqs))) {
> > -		num_irqs++;
> > -		if (num_irqs > smmu->num_global_irqs)
> > -			smmu->num_context_irqs++;
> > -	}
> > +	num_irqs = platform_irq_count(pdev);
> > +	if (num_irqs < 0)
> > +		return num_irqs;
> > +
> > +	if (num_irqs > smmu->num_global_irqs)
> > +		smmu->num_context_irqs += (num_irqs - smmu->num_global_irqs);
> 
> This seems a bit overcomplicated. I reckon:
> 
> 	smmu->num_context_irqs = num_irqs - smmu->num_global_irqs;
> 	if (num_irqs <= smmu->num_global_irqs) {
> 		dev_err(...
> 
> should do it.
> 
> However, FYI I have some patches refactoring most of the IRQ stuff here that
> I plan to post next cycle (didn't quite have time to get them done for 5.17
> as I'd hoped...), so unless this needs to go in right now as an urgent fix,
> I'm happy to take care of removing platform_get_resource() as part of that
> if it's easier.

Did you get anywhere with this? December 23rd is long forgotten by now ;)

Will
Robin Murphy Feb. 8, 2022, 3:28 p.m. UTC | #4
On 2022-02-08 15:19, Will Deacon wrote:
> On Thu, Dec 23, 2021 at 02:14:35PM +0000, Robin Murphy wrote:
>> On 2021-12-23 13:00, Lad Prabhakar wrote:
>>> platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
>>> allocation of IRQ resources in DT core code, this causes an issue
>>> when using hierarchical interrupt domains using "interrupts" property
>>> in the node as this bypasses the hierarchical setup and messes up the
>>> irq chaining.
>>>
>>> In preparation for removal of static setup of IRQ resource from DT core
>>> code use platform_get_irq_count().
>>
>> Nit: platform_irq_count()
>>
>>> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>>> ---
>>>    drivers/iommu/arm/arm-smmu/arm-smmu.c | 12 ++++++------
>>>    1 file changed, 6 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
>>> index 4bc75c4ce402..4844cd075644 100644
>>> --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
>>> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
>>> @@ -2105,12 +2105,12 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
>>>    	if (IS_ERR(smmu))
>>>    		return PTR_ERR(smmu);
>>> -	num_irqs = 0;
>>> -	while ((res = platform_get_resource(pdev, IORESOURCE_IRQ, num_irqs))) {
>>> -		num_irqs++;
>>> -		if (num_irqs > smmu->num_global_irqs)
>>> -			smmu->num_context_irqs++;
>>> -	}
>>> +	num_irqs = platform_irq_count(pdev);
>>> +	if (num_irqs < 0)
>>> +		return num_irqs;
>>> +
>>> +	if (num_irqs > smmu->num_global_irqs)
>>> +		smmu->num_context_irqs += (num_irqs - smmu->num_global_irqs);
>>
>> This seems a bit overcomplicated. I reckon:
>>
>> 	smmu->num_context_irqs = num_irqs - smmu->num_global_irqs;
>> 	if (num_irqs <= smmu->num_global_irqs) {
>> 		dev_err(...
>>
>> should do it.
>>
>> However, FYI I have some patches refactoring most of the IRQ stuff here that
>> I plan to post next cycle (didn't quite have time to get them done for 5.17
>> as I'd hoped...), so unless this needs to go in right now as an urgent fix,
>> I'm happy to take care of removing platform_get_resource() as part of that
>> if it's easier.
> 
> Did you get anywhere with this? December 23rd is long forgotten by now ;)

Yup: 
https://gitlab.arm.com/linux-arm/linux-rm/-/commit/b2a40caaf1622eb35c555074a0d72f4f0513cff9

I'm still cleaning up the PMU driver that justifies the whole thing, but 
I can send that patch now if you reckon it's not complete nonsense out 
of context. Otherwise, I'll aim to get the whole lot out next week.


Cheers,
Robin.
Will Deacon Feb. 8, 2022, 3:31 p.m. UTC | #5
On Tue, Feb 08, 2022 at 03:28:50PM +0000, Robin Murphy wrote:
> On 2022-02-08 15:19, Will Deacon wrote:
> > On Thu, Dec 23, 2021 at 02:14:35PM +0000, Robin Murphy wrote:
> > > On 2021-12-23 13:00, Lad Prabhakar wrote:
> > > > platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
> > > > allocation of IRQ resources in DT core code, this causes an issue
> > > > when using hierarchical interrupt domains using "interrupts" property
> > > > in the node as this bypasses the hierarchical setup and messes up the
> > > > irq chaining.
> > > > 
> > > > In preparation for removal of static setup of IRQ resource from DT core
> > > > code use platform_get_irq_count().
> > > 
> > > Nit: platform_irq_count()
> > > 
> > > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > > > ---
> > > >    drivers/iommu/arm/arm-smmu/arm-smmu.c | 12 ++++++------
> > > >    1 file changed, 6 insertions(+), 6 deletions(-)
> > > > 
> > > > diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> > > > index 4bc75c4ce402..4844cd075644 100644
> > > > --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
> > > > +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> > > > @@ -2105,12 +2105,12 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
> > > >    	if (IS_ERR(smmu))
> > > >    		return PTR_ERR(smmu);
> > > > -	num_irqs = 0;
> > > > -	while ((res = platform_get_resource(pdev, IORESOURCE_IRQ, num_irqs))) {
> > > > -		num_irqs++;
> > > > -		if (num_irqs > smmu->num_global_irqs)
> > > > -			smmu->num_context_irqs++;
> > > > -	}
> > > > +	num_irqs = platform_irq_count(pdev);
> > > > +	if (num_irqs < 0)
> > > > +		return num_irqs;
> > > > +
> > > > +	if (num_irqs > smmu->num_global_irqs)
> > > > +		smmu->num_context_irqs += (num_irqs - smmu->num_global_irqs);
> > > 
> > > This seems a bit overcomplicated. I reckon:
> > > 
> > > 	smmu->num_context_irqs = num_irqs - smmu->num_global_irqs;
> > > 	if (num_irqs <= smmu->num_global_irqs) {
> > > 		dev_err(...
> > > 
> > > should do it.
> > > 
> > > However, FYI I have some patches refactoring most of the IRQ stuff here that
> > > I plan to post next cycle (didn't quite have time to get them done for 5.17
> > > as I'd hoped...), so unless this needs to go in right now as an urgent fix,
> > > I'm happy to take care of removing platform_get_resource() as part of that
> > > if it's easier.
> > 
> > Did you get anywhere with this? December 23rd is long forgotten by now ;)
> 
> Yup: https://gitlab.arm.com/linux-arm/linux-rm/-/commit/b2a40caaf1622eb35c555074a0d72f4f0513cff9
> 
> I'm still cleaning up the PMU driver that justifies the whole thing, but I
> can send that patch now if you reckon it's not complete nonsense out of
> context. Otherwise, I'll aim to get the whole lot out next week.

Next week is fine, no rush. I was just trying to work out what to do with
Lad's patches in this thread and it sounds like I should ignore them and
wait for your series instead.

Will
diff mbox series

Patch

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index 4bc75c4ce402..4844cd075644 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -2105,12 +2105,12 @@  static int arm_smmu_device_probe(struct platform_device *pdev)
 	if (IS_ERR(smmu))
 		return PTR_ERR(smmu);
 
-	num_irqs = 0;
-	while ((res = platform_get_resource(pdev, IORESOURCE_IRQ, num_irqs))) {
-		num_irqs++;
-		if (num_irqs > smmu->num_global_irqs)
-			smmu->num_context_irqs++;
-	}
+	num_irqs = platform_irq_count(pdev);
+	if (num_irqs < 0)
+		return num_irqs;
+
+	if (num_irqs > smmu->num_global_irqs)
+		smmu->num_context_irqs += (num_irqs - smmu->num_global_irqs);
 
 	if (!smmu->num_context_irqs) {
 		dev_err(dev, "found %d interrupts but expected at least %d\n",