powerpc/powernv/ioda: Clean up IOMMU group registration

The existing code has 3 calls to iommu_register_group() and
all 3 branches actually cover all possible cases.

This replaces 3 calls with one and moves the registration earlier;
the latter will make more sense when we add TCE table sharing.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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

@@ -1785,6 +1785,9 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
 	if (WARN_ON(pe->tce32_seg >= 0))
 		return;
 
+	tbl = pe->tce32_table;
+	iommu_register_group(tbl, phb->hose->global_number, pe->pe_number);
+
 	/* Grab a 32-bit TCE table */
 	pe->tce32_seg = base;
 	pe_info(pe, " Setting up 32-bit TCE table at %08x..%08x\n",
@@ -1819,7 +1822,6 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
 	}
 
 	/* Setup linux iommu table */
-	tbl = pe->tce32_table;
 	pnv_pci_setup_iommu_table(tbl, addr, TCE32_TABLE_SIZE * segs,
 				  base << 28, IOMMU_PAGE_SHIFT_4K);
 
@@ -1841,8 +1843,6 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
 	iommu_init_table(tbl, phb->hose->node);
 
 	if (pe->flags & PNV_IODA_PE_DEV) {
-		iommu_register_group(tbl, phb->hose->global_number,
-				     pe->pe_number);
 		/*
 		 * Setting table base here only for carrying iommu_group
 		 * further down to let iommu_add_device() do the job.
@@ -1850,14 +1850,8 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
 		 */
 		set_iommu_table_base(&pe->pdev->dev, tbl);
 		iommu_add_device(&pe->pdev->dev);
-	} else if (pe->flags & (PNV_IODA_PE_BUS | PNV_IODA_PE_BUS_ALL)) {
+	} else if (pe->flags & (PNV_IODA_PE_BUS | PNV_IODA_PE_BUS_ALL))
-		iommu_register_group(tbl, phb->hose->global_number,
-				     pe->pe_number);
 		pnv_ioda_setup_bus_dma(pe, pe->pbus);
-	} else if (pe->flags & PNV_IODA_PE_VF) {
-		iommu_register_group(tbl, phb->hose->global_number,
-				     pe->pe_number);
-	}
 
 	return;
  fail:
@@ -1924,6 +1918,9 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
 	if (WARN_ON(pe->tce32_seg >= 0))
 		return;
 
+	tbl = pe->tce32_table;
+	iommu_register_group(tbl, phb->hose->global_number, pe->pe_number);
+
 	/* The PE will reserve all possible 32-bits space */
 	pe->tce32_seg = 0;
 	end = (1 << ilog2(phb->ioda.m32_pci_base));
@@ -1955,7 +1952,6 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
 	}
 
 	/* Setup linux iommu table */
-	tbl = pe->tce32_table;
 	pnv_pci_setup_iommu_table(tbl, addr, tce_table_size, 0,
 			IOMMU_PAGE_SHIFT_4K);
 
@@ -1975,8 +1971,6 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
 	iommu_init_table(tbl, phb->hose->node);
 
 	if (pe->flags & PNV_IODA_PE_DEV) {
-		iommu_register_group(tbl, phb->hose->global_number,
-				     pe->pe_number);
 		/*
 		 * Setting table base here only for carrying iommu_group
 		 * further down to let iommu_add_device() do the job.
@@ -1984,14 +1978,8 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
 		 */
 		set_iommu_table_base(&pe->pdev->dev, tbl);
 		iommu_add_device(&pe->pdev->dev);
-	} else if (pe->flags & (PNV_IODA_PE_BUS | PNV_IODA_PE_BUS_ALL)) {
+	} else if (pe->flags & (PNV_IODA_PE_BUS | PNV_IODA_PE_BUS_ALL))
-		iommu_register_group(tbl, phb->hose->global_number,
-				     pe->pe_number);
 		pnv_ioda_setup_bus_dma(pe, pe->pbus);
-	} else if (pe->flags & PNV_IODA_PE_VF) {
-		iommu_register_group(tbl, phb->hose->global_number,
-				     pe->pe_number);
-	}
 
 	/* Also create a bypass window */
 	if (!pnv_iommu_bypass_disabled)