[PATCH 1/7] Set archdata.dma_data for direct DMA in cell_dma_dev_setup()

@@ -495,9 +495,10 @@ static void cell_dma_dev_setup(struct device *dev)
 	struct cbe_iommu *iommu;
 	struct dev_archdata *archdata = &dev->archdata;
 
-	/* If we run without iommu, no need to do anything */
-	if (get_pci_dma_ops() == &dma_direct_ops)
+	if (get_pci_dma_ops() == &dma_direct_ops) {
+		archdata->dma_data = &dma_direct_offset;
 		return;
+	}
 
 	/* Current implementation uses the first window available in that
 	 * node's iommu. We -might- do something smarter later though it may

@@ -71,6 +71,17 @@ static void __init celleb_init_direct_mapping(void)
 	dma_direct_offset = dma_base;
 }
 
+static void celleb_dma_dev_setup(struct device *dev)
+{
+	dev->archdata.dma_ops = get_pci_dma_ops();
+	dev->archdata.dma_data = &dma_direct_offset;
+}
+
+static void celleb_pci_dma_dev_setup(struct pci_dev *pdev)
+{
+	celleb_dma_dev_setup(&pdev->dev);
+}
+
 static int celleb_of_bus_notify(struct notifier_block *nb,
 				unsigned long action, void *data)
 {

@@ -80,7 +91,7 @@ static int celleb_of_bus_notify(struct notifier_block *nb,
 	if (action != BUS_NOTIFY_ADD_DEVICE)
 		return 0;
 
-	dev->archdata.dma_ops = get_pci_dma_ops();
+	celleb_dma_dev_setup(dev);
 
 	return 0;
 }

@@ -96,6 +107,7 @@ static int __init celleb_init_iommu(void)
 
 	celleb_init_direct_mapping();
 	set_pci_dma_ops(&dma_direct_ops);
+	ppc_md.pci_dma_dev_setup = celleb_pci_dma_dev_setup;
 	bus_register_notifier(&of_platform_bus_type, &celleb_of_bus_notifier);
 
 	return 0;

@@ -117,6 +117,18 @@ EXPORT_SYMBOL(dma_iommu_ops);
  */
 unsigned long dma_direct_offset;
 
+static unsigned long get_dma_direct_offset(struct device *dev)
+{
+	unsigned long *offset;
+
+	offset = dev->archdata.dma_data;
+
+	if (offset)
+		return *offset;
+
+	return 0;
+}
+
 static void *dma_direct_alloc_coherent(struct device *dev, size_t size,
 				       dma_addr_t *dma_handle, gfp_t flag)
 {

@@ -130,7 +142,7 @@ static void *dma_direct_alloc_coherent(struct device *dev, size_t size,
 		return NULL;
 	ret = page_address(page);
 	memset(ret, 0, size);
-	*dma_handle = virt_to_abs(ret) | dma_direct_offset;
+	*dma_handle = virt_to_abs(ret) | get_dma_direct_offset(dev);
 
 	return ret;
 }

@@ -145,7 +157,7 @@ static dma_addr_t dma_direct_map_single(struct device *dev, void *ptr,
 					size_t size,
 					enum dma_data_direction direction)
 {
-	return virt_to_abs(ptr) | dma_direct_offset;
+	return virt_to_abs(ptr) | get_dma_direct_offset(dev);
 }
 
 static void dma_direct_unmap_single(struct device *dev, dma_addr_t dma_addr,

@@ -161,7 +173,7 @@ static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
 	int i;
 
 	for_each_sg(sgl, sg, nents, i) {
-		sg->dma_address = sg_phys(sg) | dma_direct_offset;
+		sg->dma_address = sg_phys(sg) | get_dma_direct_offset(dev);
 		sg->dma_length = sg->length;
 	}
 

@@ -489,6 +489,8 @@ static struct cbe_iommu *cell_iommu_for_node(int nid)
 	return NULL;
 }
 
+static unsigned long cell_dma_direct_offset;
+
 static void cell_dma_dev_setup(struct device *dev)
 {
 	struct iommu_window *window;

@@ -496,7 +498,7 @@ static void cell_dma_dev_setup(struct device *dev)
 	struct dev_archdata *archdata = &dev->archdata;
 
 	if (get_pci_dma_ops() == &dma_direct_ops) {
-		archdata->dma_data = &dma_direct_offset;
+		archdata->dma_data = &cell_dma_direct_offset;
 		return;
 	}
 

@@ -654,7 +656,7 @@ static int __init cell_iommu_init_disabled(void)
 
 	/* If we have no Axon, we set up the spider DMA magic offset */
 	if (of_find_node_by_name(NULL, "axon") == NULL)
-		dma_direct_offset = SPIDER_DMA_OFFSET;
+		cell_dma_direct_offset = SPIDER_DMA_OFFSET;
 
 	/* Now we need to check to see where the memory is mapped
 	 * in PCI space. We assume that all busses use the same dma

@@ -688,10 +690,10 @@ static int __init cell_iommu_init_disabled(void)
 		return -ENODEV;
 	}
 
-	dma_direct_offset += base;
+	cell_dma_direct_offset += base;
 
 	printk("iommu: disabled, direct DMA offset is 0x%lx\n",
-	       dma_direct_offset);
+	       cell_dma_direct_offset);
 
 	return 0;
 }

@@ -51,6 +51,8 @@ static int __init find_dma_window(u64 *io_space_id, u64 *ioid,
 	return 0;
 }
 
+static unsigned long celleb_dma_direct_offset;
+
 static void __init celleb_init_direct_mapping(void)
 {
 	u64 lpar_addr, io_addr;

@@ -68,13 +70,13 @@ static void __init celleb_init_direct_mapping(void)
 				     ioid, DMA_FLAGS);
 	}
 
-	dma_direct_offset = dma_base;
+	celleb_dma_direct_offset = dma_base;
 }
 
 static void celleb_dma_dev_setup(struct device *dev)
 {
 	dev->archdata.dma_ops = get_pci_dma_ops();
-	dev->archdata.dma_data = &dma_direct_offset;
+	dev->archdata.dma_data = &celleb_dma_direct_offset;
 }
 
 static void celleb_pci_dma_dev_setup(struct pci_dev *pdev)

@@ -112,10 +112,11 @@ EXPORT_SYMBOL(dma_iommu_ops);
 /*
  * Generic direct DMA implementation
  *
- * This implementation supports a global offset that can be applied if
- * the address at which memory is visible to devices is not 0.
+ * This implementation supports a per-device offset that can be applied if
+ * the address at which memory is visible to devices is not 0. Platform code
+ * can point archdata.dma_data at an unsigned long holding the offset. By
+ * default no offset is used.
  */
-unsigned long dma_direct_offset;
 
 static unsigned long get_dma_direct_offset(struct device *dev)
 {

@@ -186,8 +186,6 @@ static inline void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
 extern struct dma_mapping_ops dma_iommu_ops;
 extern struct dma_mapping_ops dma_direct_ops;
 
-extern unsigned long dma_direct_offset;
-
 #else /* CONFIG_PPC64 */
 
 #define dma_supported(dev, mask)	(1)

@@ -137,7 +137,6 @@ static void *dma_direct_alloc_coherent(struct device *dev, size_t size,
 	void *ret;
 	int node = dev->archdata.numa_node;
 
-	/* TODO: Maybe use the numa node here too ? */
 	page = alloc_pages_node(node, flag, get_order(size));
 	if (page == NULL)
 		return NULL;