[PATCH v3 2/6] powerpc/powernv: simplify the calculation of iov resource alignment

Gavin Shan gwshan at linux.vnet.ibm.com
Fri Aug 14 11:04:58 AEST 2015


On Thu, Aug 13, 2015 at 10:11:07PM +0800, Wei Yang wrote:
>The alignment of IOV BAR on PowerNV platform is the total size of the IOV
>BAR. No matter whether the IOV BAR is extended with number of
>roundup_pow_of_two(total_vfs) or number of max PE number (256), the total
>size could be calculated by (vfs_expanded * VF_BAR_size).
>
>This patch simplifies the pnv_pci_iov_resource_alignment() by removing the
>first case.
>
>Signed-off-by: Wei Yang <weiyang at linux.vnet.ibm.com>
>Reviewed-by: Gavin Shan <gwshan at linux.vnet.ibm.com>
>---
> arch/powerpc/platforms/powernv/pci-ioda.c |   14 +++++++++-----
> 1 file changed, 9 insertions(+), 5 deletions(-)
>
>diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
>index 9ac324e..67b8f72 100644
>--- a/arch/powerpc/platforms/powernv/pci-ioda.c
>+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
>@@ -2987,12 +2987,16 @@ static resource_size_t pnv_pci_iov_resource_alignment(struct pci_dev *pdev,
> 						      int resno)
> {
> 	struct pci_dn *pdn = pci_get_pdn(pdev);
>-	resource_size_t align, iov_align;
>-
>-	iov_align = resource_size(&pdev->resource[resno]);
>-	if (iov_align)
>-		return iov_align;
>+	resource_size_t align;
>
>+	/*
>+	 * On PowerNV platform, IOV BAR is mapped by M64 BAR to enable the
>+	 * SR-IOV. While from hardware perspective, the range mapped by M64
>+	 * BAR should be size aligned.
>+	 *
>+	 * This function return the total IOV BAR size if expanded or just the
>+	 * individual size if not.
>+	 */

s/return/returns

> 	align = pci_iov_resource_size(pdev, resno);
> 	if (pdn->vfs_expanded)
> 		return pdn->vfs_expanded * align;
>-- 
>1.7.9.5
>



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