diff mbox

[RFC/RFT,2/2] ARM64: kernel: pci: implement PCI device resources claiming

Message ID 1431614537-16136-2-git-send-email-lorenzo.pieralisi@arm.com (mailing list archive)
State New, archived
Headers show

Commit Message

Lorenzo Pieralisi May 14, 2015, 2:42 p.m. UTC
When a device is scanned and added to the PCI bus, its resources
should be claimed to validate the BARs configuration and to assign
them a parent resource so that the resource hierarchy can be sanity
checked.

This patch adds code that carries out PCI device resources claiming to
the ARM64 pcibios_add_device implementation so that device resources
are claimed by the core PCI layer upon PCI device initialization on
ARM64 systems.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
---
 arch/arm64/kernel/pci.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

Comments

Bjorn Helgaas May 19, 2015, 11:25 p.m. UTC | #1
Hi Lorenzo,

On Thu, May 14, 2015 at 03:42:16PM +0100, Lorenzo Pieralisi wrote:
> When a device is scanned and added to the PCI bus, its resources
> should be claimed to validate the BARs configuration and to assign
> them a parent resource so that the resource hierarchy can be sanity
> checked.
> 
> This patch adds code that carries out PCI device resources claiming to
> the ARM64 pcibios_add_device implementation so that device resources
> are claimed by the core PCI layer upon PCI device initialization on
> ARM64 systems.
> 
> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: Will Deacon <will.deacon@arm.com>
> Cc: Liviu Dudau <liviu.dudau@arm.com>
> Cc: Bjorn Helgaas <bhelgaas@google.com>

Seems like Suravee proposed a tweak?  Can you post a v2 with that
incorporated if necessary?

Bjorn

> ---
>  arch/arm64/kernel/pci.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c
> index 4095379..c0a88ca 100644
> --- a/arch/arm64/kernel/pci.c
> +++ b/arch/arm64/kernel/pci.c
> @@ -43,8 +43,18 @@ resource_size_t pcibios_align_resource(void *data, const struct resource *res,
>   */
>  int pcibios_add_device(struct pci_dev *dev)
>  {
> +	struct resource *res;
> +	int i;
> +
>  	dev->irq = of_irq_parse_and_map_pci(dev, 0, 0);
>  
> +	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
> +		res = &dev->resource[i];
> +		if (res->parent || !res->flags)
> +			continue;
> +		pci_claim_resource(dev, i);
> +	}
> +
>  	return 0;
>  }
>  
> -- 
> 2.2.1
> 
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Lorenzo Pieralisi May 20, 2015, 9:16 a.m. UTC | #2
Hi Bjorn,

On Wed, May 20, 2015 at 12:25:31AM +0100, Bjorn Helgaas wrote:
> Hi Lorenzo,
> 
> On Thu, May 14, 2015 at 03:42:16PM +0100, Lorenzo Pieralisi wrote:
> > When a device is scanned and added to the PCI bus, its resources
> > should be claimed to validate the BARs configuration and to assign
> > them a parent resource so that the resource hierarchy can be sanity
> > checked.
> > 
> > This patch adds code that carries out PCI device resources claiming to
> > the ARM64 pcibios_add_device implementation so that device resources
> > are claimed by the core PCI layer upon PCI device initialization on
> > ARM64 systems.
> > 
> > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> > Cc: Arnd Bergmann <arnd@arndb.de>
> > Cc: Will Deacon <will.deacon@arm.com>
> > Cc: Liviu Dudau <liviu.dudau@arm.com>
> > Cc: Bjorn Helgaas <bhelgaas@google.com>
> 
> Seems like Suravee proposed a tweak?  Can you post a v2 with that
> incorporated if necessary?

I can post a v2, but I am not happy about that tweak, I want to
understand why pci_read_bridge_bases has to be executed only on
PCI_PROBE_ONLY systems and why it can't be done in generic code in the
first place - ie pci_scan_child_bus(), I guess as I mentioned that in
some archs this can trigger regressions, if you have an opinion please
let me know, when we agree I will drop a v2 on the lists.

Thanks,
Lorenzo

> Bjorn
> 
> > ---
> >  arch/arm64/kernel/pci.c | 10 ++++++++++
> >  1 file changed, 10 insertions(+)
> > 
> > diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c
> > index 4095379..c0a88ca 100644
> > --- a/arch/arm64/kernel/pci.c
> > +++ b/arch/arm64/kernel/pci.c
> > @@ -43,8 +43,18 @@ resource_size_t pcibios_align_resource(void *data, const struct resource *res,
> >   */
> >  int pcibios_add_device(struct pci_dev *dev)
> >  {
> > +	struct resource *res;
> > +	int i;
> > +
> >  	dev->irq = of_irq_parse_and_map_pci(dev, 0, 0);
> >  
> > +	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
> > +		res = &dev->resource[i];
> > +		if (res->parent || !res->flags)
> > +			continue;
> > +		pci_claim_resource(dev, i);
> > +	}
> > +
> >  	return 0;
> >  }
> >  
> > -- 
> > 2.2.1
> > 
> 
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diff mbox

Patch

diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c
index 4095379..c0a88ca 100644
--- a/arch/arm64/kernel/pci.c
+++ b/arch/arm64/kernel/pci.c
@@ -43,8 +43,18 @@  resource_size_t pcibios_align_resource(void *data, const struct resource *res,
  */
 int pcibios_add_device(struct pci_dev *dev)
 {
+	struct resource *res;
+	int i;
+
 	dev->irq = of_irq_parse_and_map_pci(dev, 0, 0);
 
+	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
+		res = &dev->resource[i];
+		if (res->parent || !res->flags)
+			continue;
+		pci_claim_resource(dev, i);
+	}
+
 	return 0;
 }