powerpc/pseries/iommu: Reorganize iommu_table_setparms*() with new helper

Add a new helper _iommu_table_setparms(), and use it in
iommu_table_setparms() and iommu_table_setparms_lpar() to avoid duplicated
code.

Also, setting tbl->it_ops was happening outsite iommu_table_setparms*(),
so move it to the new helper. Since we need the iommu_table_ops to be
declared before used, declare iommu_table_lpar_multi_ops and
iommu_table_pseries_ops to before their respective iommu_table_setparms*().
Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210817063929.38701-8-leobras.c@gmail.com

arch/powerpc/platforms/pseries/iommu.c

@@ -501,6 +501,24 @@ static int tce_setrange_multi_pSeriesLP_walk(unsigned long start_pfn,
 	return tce_setrange_multi_pSeriesLP(start_pfn, num_pfn, arg);
 }
 
+static void iommu_table_setparms_common(struct iommu_table *tbl, unsigned long busno,
+					unsigned long liobn, unsigned long win_addr,
+					unsigned long window_size, unsigned long page_shift,
+					void *base, struct iommu_table_ops *table_ops)
+{
+	tbl->it_busno = busno;
+	tbl->it_index = liobn;
+	tbl->it_offset = win_addr >> page_shift;
+	tbl->it_size = window_size >> page_shift;
+	tbl->it_page_shift = page_shift;
+	tbl->it_base = (unsigned long)base;
+	tbl->it_blocksize = 16;
+	tbl->it_type = TCE_PCI;
+	tbl->it_ops = table_ops;
+}
+
+struct iommu_table_ops iommu_table_pseries_ops;
+
 static void iommu_table_setparms(struct pci_controller *phb,
 				 struct device_node *dn,
 				 struct iommu_table *tbl)
@@ -509,8 +527,13 @@ static void iommu_table_setparms(struct pci_controller *phb,
 	const unsigned long *basep;
 	const u32 *sizep;
 
-	node = phb->dn;
+	/* Test if we are going over 2GB of DMA space */
+	if (phb->dma_window_base_cur + phb->dma_window_size > SZ_2G) {
+		udbg_printf("PCI_DMA: Unexpected number of IOAs under this PHB.\n");
+		panic("PCI_DMA: Unexpected number of IOAs under this PHB.\n");
+	}
 
+	node = phb->dn;
 	basep = of_get_property(node, "linux,tce-base", NULL);
 	sizep = of_get_property(node, "linux,tce-size", NULL);
 	if (basep == NULL || sizep == NULL) {
@@ -519,33 +542,18 @@ static void iommu_table_setparms(struct pci_controller *phb,
 		return;
 	}
 
-	tbl->it_base = (unsigned long)__va(*basep);
+	iommu_table_setparms_common(tbl, phb->bus->number, 0, phb->dma_window_base_cur,
+				    phb->dma_window_size, IOMMU_PAGE_SHIFT_4K,
+				    __va(*basep), &iommu_table_pseries_ops);
 
 	if (!is_kdump_kernel())
 		memset((void *)tbl->it_base, 0, *sizep);
 
-	tbl->it_busno = phb->bus->number;
-	tbl->it_page_shift = IOMMU_PAGE_SHIFT_4K;
-
-	/* Units of tce entries */
-	tbl->it_offset = phb->dma_window_base_cur >> tbl->it_page_shift;
-
-	/* Test if we are going over 2GB of DMA space */
-	if (phb->dma_window_base_cur + phb->dma_window_size > 0x80000000ul) {
-		udbg_printf("PCI_DMA: Unexpected number of IOAs under this PHB.\n");
-		panic("PCI_DMA: Unexpected number of IOAs under this PHB.\n");
-	}
-
 	phb->dma_window_base_cur += phb->dma_window_size;
-
-	/* Set the tce table size - measured in entries */
-	tbl->it_size = phb->dma_window_size >> tbl->it_page_shift;
-
-	tbl->it_index = 0;
-	tbl->it_blocksize = 16;
-	tbl->it_type = TCE_PCI;
 }
 
+struct iommu_table_ops iommu_table_lpar_multi_ops;
+
 /*
  * iommu_table_setparms_lpar
  *
@@ -557,17 +565,13 @@ static void iommu_table_setparms_lpar(struct pci_controller *phb,
 				      struct iommu_table_group *table_group,
 				      const __be32 *dma_window)
 {
-	unsigned long offset, size;
+	unsigned long offset, size, liobn;
 
-	of_parse_dma_window(dn, dma_window, &tbl->it_index, &offset, &size);
+	of_parse_dma_window(dn, dma_window, &liobn, &offset, &size);
+
+	iommu_table_setparms_common(tbl, phb->bus->number, liobn, offset, size, IOMMU_PAGE_SHIFT_4K, NULL,
+				    &iommu_table_lpar_multi_ops);
 
-	tbl->it_busno = phb->bus->number;
-	tbl->it_page_shift = IOMMU_PAGE_SHIFT_4K;
-	tbl->it_base   = 0;
-	tbl->it_blocksize  = 16;
-	tbl->it_type = TCE_PCI;
-	tbl->it_offset = offset >> tbl->it_page_shift;
-	tbl->it_size = size >> tbl->it_page_shift;
 
 	table_group->tce32_start = offset;
 	table_group->tce32_size = size;
@@ -647,7 +651,7 @@ static void pci_dma_bus_setup_pSeries(struct pci_bus *bus)
 	tbl = pci->table_group->tables[0];
 
 	iommu_table_setparms(pci->phb, dn, tbl);
-	tbl->it_ops = &iommu_table_pseries_ops;
+
 	if (!iommu_init_table(tbl, pci->phb->node, 0, 0))
 		panic("Failed to initialize iommu table");
 
@@ -730,7 +734,7 @@ static void pci_dma_bus_setup_pSeriesLP(struct pci_bus *bus)
 		tbl = ppci->table_group->tables[0];
 		iommu_table_setparms_lpar(ppci->phb, pdn, tbl,
 				ppci->table_group, dma_window);
-		tbl->it_ops = &iommu_table_lpar_multi_ops;
+
 		if (!iommu_init_table(tbl, ppci->phb->node, 0, 0))
 			panic("Failed to initialize iommu table");
 		iommu_register_group(ppci->table_group,
@@ -760,7 +764,7 @@ static void pci_dma_dev_setup_pSeries(struct pci_dev *dev)
 		PCI_DN(dn)->table_group = iommu_pseries_alloc_group(phb->node);
 		tbl = PCI_DN(dn)->table_group->tables[0];
 		iommu_table_setparms(phb, dn, tbl);
-		tbl->it_ops = &iommu_table_pseries_ops;
+
 		if (!iommu_init_table(tbl, phb->node, 0, 0))
 			panic("Failed to initialize iommu table");
 
@@ -1461,7 +1465,7 @@ static void pci_dma_dev_setup_pSeriesLP(struct pci_dev *dev)
 		tbl = pci->table_group->tables[0];
 		iommu_table_setparms_lpar(pci->phb, pdn, tbl,
 				pci->table_group, dma_window);
-		tbl->it_ops = &iommu_table_lpar_multi_ops;
+
 		iommu_init_table(tbl, pci->phb->node, 0, 0);
 		iommu_register_group(pci->table_group,
 				pci_domain_nr(pci->phb->bus), 0);