powerpc/powernv: Implement pcibios_iov_resource_alignment() on powernv

Implement pcibios_iov_resource_alignment() on powernv platform.

On PowerNV platform, there are 3 cases for the IOV BAR:
1. initial state, the IOV BAR size is multiple times of VF BAR size
2. after expanded, the IOV BAR size is expanded to meet the M64 segment size
3. sizing stage, the IOV BAR is truncated to 0

pnv_pci_iov_resource_alignment() handle these three cases respectively.

[bhelgaas: adjust to drop "align" parameter, return pci_iov_resource_size()
if no ppc_md machdep_call version]
Signed-off-by: Wei Yang <[e-mail]>
Signed-off-by: Benjamin Herrenschmidt <[e-mail]>

arch/powerpc/include/asm/machdep.h

···
 
 #ifdef CONFIG_PCI_IOV
 	void (*pcibios_fixup_sriov)(struct pci_dev *pdev);
+	resource_size_t (*pcibios_iov_resource_alignment)(struct pci_dev *, int resno);
 #endif /* CONFIG_PCI_IOV */
 
 	/* Called to shutdown machine specific hardware not already controlled

arch/powerpc/kernel/pci-common.c

···
 	pci_reset_secondary_bus(dev);
 }
 
+#ifdef CONFIG_PCI_IOV
+resource_size_t pcibios_iov_resource_alignment(struct pci_dev *pdev, int resno)
+{
+	if (ppc_md.pcibios_iov_resource_alignment)
+		return ppc_md.pcibios_iov_resource_alignment(pdev, resno);
+
+	return pci_iov_resource_size(pdev, resno);
+}
+#endif /* CONFIG_PCI_IOV */
+
 static resource_size_t pcibios_io_size(const struct pci_controller *hose)
 {
 #ifdef CONFIG_PPC64

arch/powerpc/platforms/powernv/pci-ioda.c

···
 	return phb->ioda.io_segsize;
 }
 
+#ifdef CONFIG_PCI_IOV
+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;
+
+	align = pci_iov_resource_size(pdev, resno);
+	if (pdn->vfs_expanded)
+		return pdn->vfs_expanded * align;
+
+	return align;
+}
+#endif /* CONFIG_PCI_IOV */
+
 /* Prevent enabling devices for which we couldn't properly
  * assign a PE
  */
···
 	ppc_md.pcibios_reset_secondary_bus = pnv_pci_reset_secondary_bus;
 #ifdef CONFIG_PCI_IOV
 	ppc_md.pcibios_fixup_sriov = pnv_pci_ioda_fixup_iov_resources;
+	ppc_md.pcibios_iov_resource_alignment = pnv_pci_iov_resource_alignment;
 #endif /* CONFIG_PCI_IOV */
 	pci_add_flags(PCI_REASSIGN_ALL_RSRC);