Commit | Line | Data |
---|---|---|
ec3cf2ec BB |
1 | /* |
2 | * Contains routines needed to support swiotlb for ppc. | |
3 | * | |
4 | * Copyright (C) 2009 Becky Bruce, Freescale Semiconductor | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify it | |
7 | * under the terms of the GNU General Public License as published by the | |
8 | * Free Software Foundation; either version 2 of the License, or (at your | |
9 | * option) any later version. | |
10 | * | |
11 | */ | |
12 | ||
13 | #include <linux/dma-mapping.h> | |
14 | #include <linux/pfn.h> | |
15 | #include <linux/of_platform.h> | |
16 | #include <linux/platform_device.h> | |
17 | #include <linux/pci.h> | |
18 | ||
19 | #include <asm/machdep.h> | |
20 | #include <asm/swiotlb.h> | |
21 | #include <asm/dma.h> | |
22 | #include <asm/abs_addr.h> | |
23 | ||
24 | int swiotlb __read_mostly; | |
25 | unsigned int ppc_swiotlb_enable; | |
26 | ||
27 | void *swiotlb_bus_to_virt(struct device *hwdev, dma_addr_t addr) | |
28 | { | |
29 | unsigned long pfn = PFN_DOWN(swiotlb_bus_to_phys(hwdev, addr)); | |
30 | void *pageaddr = page_address(pfn_to_page(pfn)); | |
31 | ||
32 | if (pageaddr != NULL) | |
33 | return pageaddr + (addr % PAGE_SIZE); | |
34 | return NULL; | |
35 | } | |
36 | ||
37 | dma_addr_t swiotlb_phys_to_bus(struct device *hwdev, phys_addr_t paddr) | |
38 | { | |
39 | return paddr + get_dma_direct_offset(hwdev); | |
40 | } | |
41 | ||
42 | phys_addr_t swiotlb_bus_to_phys(struct device *hwdev, dma_addr_t baddr) | |
43 | ||
44 | { | |
45 | return baddr - get_dma_direct_offset(hwdev); | |
46 | } | |
47 | ||
48 | /* | |
49 | * Determine if an address needs bounce buffering via swiotlb. | |
50 | * Going forward I expect the swiotlb code to generalize on using | |
51 | * a dma_ops->addr_needs_map, and this function will move from here to the | |
52 | * generic swiotlb code. | |
53 | */ | |
54 | int | |
55 | swiotlb_arch_address_needs_mapping(struct device *hwdev, dma_addr_t addr, | |
56 | size_t size) | |
57 | { | |
58 | struct dma_mapping_ops *dma_ops = get_dma_ops(hwdev); | |
59 | ||
60 | BUG_ON(!dma_ops); | |
61 | return dma_ops->addr_needs_map(hwdev, addr, size); | |
62 | } | |
63 | ||
64 | /* | |
65 | * Determine if an address is reachable by a pci device, or if we must bounce. | |
66 | */ | |
67 | static int | |
68 | swiotlb_pci_addr_needs_map(struct device *hwdev, dma_addr_t addr, size_t size) | |
69 | { | |
70 | u64 mask = dma_get_mask(hwdev); | |
71 | dma_addr_t max; | |
72 | struct pci_controller *hose; | |
73 | struct pci_dev *pdev = to_pci_dev(hwdev); | |
74 | ||
75 | hose = pci_bus_to_host(pdev->bus); | |
76 | max = hose->dma_window_base_cur + hose->dma_window_size; | |
77 | ||
78 | /* check that we're within mapped pci window space */ | |
79 | if ((addr + size > max) | (addr < hose->dma_window_base_cur)) | |
80 | return 1; | |
81 | ||
82 | return !is_buffer_dma_capable(mask, addr, size); | |
83 | } | |
84 | ||
85 | static int | |
86 | swiotlb_addr_needs_map(struct device *hwdev, dma_addr_t addr, size_t size) | |
87 | { | |
88 | return !is_buffer_dma_capable(dma_get_mask(hwdev), addr, size); | |
89 | } | |
90 | ||
91 | ||
92 | /* | |
93 | * At the moment, all platforms that use this code only require | |
94 | * swiotlb to be used if we're operating on HIGHMEM. Since | |
95 | * we don't ever call anything other than map_sg, unmap_sg, | |
96 | * map_page, and unmap_page on highmem, use normal dma_ops | |
97 | * for everything else. | |
98 | */ | |
99 | struct dma_mapping_ops swiotlb_dma_ops = { | |
100 | .alloc_coherent = dma_direct_alloc_coherent, | |
101 | .free_coherent = dma_direct_free_coherent, | |
102 | .map_sg = swiotlb_map_sg_attrs, | |
103 | .unmap_sg = swiotlb_unmap_sg_attrs, | |
104 | .dma_supported = swiotlb_dma_supported, | |
105 | .map_page = swiotlb_map_page, | |
106 | .unmap_page = swiotlb_unmap_page, | |
107 | .addr_needs_map = swiotlb_addr_needs_map, | |
108 | .sync_single_range_for_cpu = swiotlb_sync_single_range_for_cpu, | |
109 | .sync_single_range_for_device = swiotlb_sync_single_range_for_device, | |
110 | .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu, | |
111 | .sync_sg_for_device = swiotlb_sync_sg_for_device | |
112 | }; | |
113 | ||
114 | struct dma_mapping_ops swiotlb_pci_dma_ops = { | |
115 | .alloc_coherent = dma_direct_alloc_coherent, | |
116 | .free_coherent = dma_direct_free_coherent, | |
117 | .map_sg = swiotlb_map_sg_attrs, | |
118 | .unmap_sg = swiotlb_unmap_sg_attrs, | |
119 | .dma_supported = swiotlb_dma_supported, | |
120 | .map_page = swiotlb_map_page, | |
121 | .unmap_page = swiotlb_unmap_page, | |
122 | .addr_needs_map = swiotlb_pci_addr_needs_map, | |
123 | .sync_single_range_for_cpu = swiotlb_sync_single_range_for_cpu, | |
124 | .sync_single_range_for_device = swiotlb_sync_single_range_for_device, | |
125 | .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu, | |
126 | .sync_sg_for_device = swiotlb_sync_sg_for_device | |
127 | }; | |
128 | ||
129 | static int ppc_swiotlb_bus_notify(struct notifier_block *nb, | |
130 | unsigned long action, void *data) | |
131 | { | |
132 | struct device *dev = data; | |
133 | ||
134 | /* We are only intereted in device addition */ | |
135 | if (action != BUS_NOTIFY_ADD_DEVICE) | |
136 | return 0; | |
137 | ||
138 | /* May need to bounce if the device can't address all of DRAM */ | |
139 | if (dma_get_mask(dev) < lmb_end_of_DRAM()) | |
140 | set_dma_ops(dev, &swiotlb_dma_ops); | |
141 | ||
142 | return NOTIFY_DONE; | |
143 | } | |
144 | ||
145 | static struct notifier_block ppc_swiotlb_plat_bus_notifier = { | |
146 | .notifier_call = ppc_swiotlb_bus_notify, | |
147 | .priority = 0, | |
148 | }; | |
149 | ||
150 | static struct notifier_block ppc_swiotlb_of_bus_notifier = { | |
151 | .notifier_call = ppc_swiotlb_bus_notify, | |
152 | .priority = 0, | |
153 | }; | |
154 | ||
155 | int __init swiotlb_setup_bus_notifier(void) | |
156 | { | |
157 | bus_register_notifier(&platform_bus_type, | |
158 | &ppc_swiotlb_plat_bus_notifier); | |
159 | bus_register_notifier(&of_platform_bus_type, | |
160 | &ppc_swiotlb_of_bus_notifier); | |
161 | ||
162 | return 0; | |
163 | } |