[PATCH] powernv/pci: Fix m64 checks for SR-IOV and window alignment

[Alexey Kardashevskiy]

On 14/09/16 16:37, Russell Currey wrote:
> Commit 5958d19a143e checks for prefetchable m64 BARs by comparing the
> addresses instead of using resource flags.  This broke SR-IOV as the m64
> check in pnv_pci_ioda_fixup_iov_resources() fails.
> 
> The condition in pnv_pci_window_alignment() also changed to checking
> only IORESOURCE_MEM_64 instead of both IORESOURCE_MEM_64 and
> IORESOURCE_PREFETCH.
> 
> Revert these cases to the previous behaviour, adding a new helper function
> to do so.  This is named pnv_pci_is_m64_flags() to make it clear this
> function is only looking at resource flags and should not be relied on for
> non-SRIOV resources.
> 
> Fixes: 5958d19a143e ("Fix incorrect PE reservation attempt on some 64-bit BARs")
> Reported-by: Alexey Kardashevskiy <aik at ozlabs.ru>
> Signed-off-by: Russell Currey <ruscur at russell.cc>

Tested-by: Alexey Kardashevskiy <aik at ozlabs.ru>


> ---
>  arch/powerpc/platforms/powernv/pci-ioda.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
> index c16d790..2f25622 100644
> --- a/arch/powerpc/platforms/powernv/pci-ioda.c
> +++ b/arch/powerpc/platforms/powernv/pci-ioda.c
> @@ -124,6 +124,13 @@ static inline bool pnv_pci_is_m64(struct pnv_phb *phb, struct resource *r)
>  		r->start < (phb->ioda.m64_base + phb->ioda.m64_size));
>  }
>  
> +static inline bool pnv_pci_is_m64_flags(unsigned long resource_flags)
> +{
> +	unsigned long flags = (IORESOURCE_MEM_64 | IORESOURCE_PREFETCH);
> +
> +	return (resource_flags & flags) == flags;
> +}
> +
>  static struct pnv_ioda_pe *pnv_ioda_init_pe(struct pnv_phb *phb, int pe_no)
>  {
>  	phb->ioda.pe_array[pe_no].phb = phb;
> @@ -2871,7 +2878,7 @@ static void pnv_pci_ioda_fixup_iov_resources(struct pci_dev *pdev)
>  		res = &pdev->resource[i + PCI_IOV_RESOURCES];
>  		if (!res->flags || res->parent)
>  			continue;
> -		if (!pnv_pci_is_m64(phb, res)) {
> +		if (!pnv_pci_is_m64_flags(res->flags)) {
>  			dev_warn(&pdev->dev, "Don't support SR-IOV with"
>  					" non M64 VF BAR%d: %pR. \n",
>  				 i, res);
> @@ -3096,7 +3103,7 @@ static resource_size_t pnv_pci_window_alignment(struct pci_bus *bus,
>  	 * alignment for any 64-bit resource, PCIe doesn't care and
>  	 * bridges only do 64-bit prefetchable anyway.
>  	 */
> -	if (phb->ioda.m64_segsize && (type & IORESOURCE_MEM_64))
> +	if (phb->ioda.m64_segsize && pnv_pci_is_m64_flags(type))
>  		return phb->ioda.m64_segsize;
>  	if (type & IORESOURCE_MEM)
>  		return phb->ioda.m32_segsize;
> 


-- 
Alexey