1 /*
2 * Contains routines needed to support swiotlb for ppc.
3 *
4 * Copyright (C) 2009-2010 Freescale Semiconductor, Inc.
5 * Author: Becky Bruce
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2 of the License, or (at your
10 * option) any later version.
11 *
12 */
13
14 #include <linux/dma-mapping.h>
15 #include <linux/pfn.h>
16 #include <linux/of_platform.h>
17 #include <linux/platform_device.h>
18 #include <linux/pci.h>
19
20 #include <asm/machdep.h>
21 #include <asm/swiotlb.h>
22 #include <asm/dma.h>
23 #include <asm/abs_addr.h>
24
25 unsigned int ppc_swiotlb_enable;
26
27 /*
28 * At the moment, all platforms that use this code only require
29 * swiotlb to be used if we're operating on HIGHMEM. Since
30 * we don't ever call anything other than map_sg, unmap_sg,
31 * map_page, and unmap_page on highmem, use normal dma_ops
32 * for everything else.
33 */
34 struct dma_map_ops swiotlb_dma_ops = {
35 .alloc_coherent = dma_direct_alloc_coherent,
36 .free_coherent = dma_direct_free_coherent,
37 .map_sg = swiotlb_map_sg_attrs,
38 .unmap_sg = swiotlb_unmap_sg_attrs,
39 .dma_supported = swiotlb_dma_supported,
40 .map_page = swiotlb_map_page,
41 .unmap_page = swiotlb_unmap_page,
42 .sync_single_for_cpu = swiotlb_sync_single_for_cpu,
43 .sync_single_for_device = swiotlb_sync_single_for_device,
44 .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
45 .sync_sg_for_device = swiotlb_sync_sg_for_device,
46 .mapping_error = swiotlb_dma_mapping_error,
47 };
48
pci_dma_dev_setup_swiotlb(struct pci_dev * pdev)49 void pci_dma_dev_setup_swiotlb(struct pci_dev *pdev)
50 {
51 struct pci_controller *hose;
52 struct dev_archdata *sd;
53
54 hose = pci_bus_to_host(pdev->bus);
55 sd = &pdev->dev.archdata;
56 sd->max_direct_dma_addr =
57 hose->dma_window_base_cur + hose->dma_window_size;
58 }
59
ppc_swiotlb_bus_notify(struct notifier_block * nb,unsigned long action,void * data)60 static int ppc_swiotlb_bus_notify(struct notifier_block *nb,
61 unsigned long action, void *data)
62 {
63 struct device *dev = data;
64 struct dev_archdata *sd;
65
66 /* We are only intereted in device addition */
67 if (action != BUS_NOTIFY_ADD_DEVICE)
68 return 0;
69
70 sd = &dev->archdata;
71 sd->max_direct_dma_addr = 0;
72
73 /* May need to bounce if the device can't address all of DRAM */
74 if ((dma_get_mask(dev) + 1) < memblock_end_of_DRAM())
75 set_dma_ops(dev, &swiotlb_dma_ops);
76
77 return NOTIFY_DONE;
78 }
79
80 static struct notifier_block ppc_swiotlb_plat_bus_notifier = {
81 .notifier_call = ppc_swiotlb_bus_notify,
82 .priority = 0,
83 };
84
swiotlb_setup_bus_notifier(void)85 int __init swiotlb_setup_bus_notifier(void)
86 {
87 bus_register_notifier(&platform_bus_type,
88 &ppc_swiotlb_plat_bus_notifier);
89 return 0;
90 }
91