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-rw-r--r--arch/ia64/kernel/pci-dma.c129
1 files changed, 129 insertions, 0 deletions
diff --git a/arch/ia64/kernel/pci-dma.c b/arch/ia64/kernel/pci-dma.c
new file mode 100644
index 000000000000..10a75b557650
--- /dev/null
+++ b/arch/ia64/kernel/pci-dma.c
@@ -0,0 +1,129 @@
1/*
2 * Dynamic DMA mapping support.
3 */
4
5#include <linux/types.h>
6#include <linux/mm.h>
7#include <linux/string.h>
8#include <linux/pci.h>
9#include <linux/module.h>
10#include <linux/dmar.h>
11#include <asm/iommu.h>
12#include <asm/machvec.h>
13#include <linux/dma-mapping.h>
14
15#include <asm/machvec.h>
16#include <asm/system.h>
17
18#ifdef CONFIG_DMAR
19
20#include <linux/kernel.h>
21#include <linux/string.h>
22
23#include <asm/page.h>
24#include <asm/iommu.h>
25
26dma_addr_t bad_dma_address __read_mostly;
27EXPORT_SYMBOL(bad_dma_address);
28
29static int iommu_sac_force __read_mostly;
30
31int no_iommu __read_mostly;
32#ifdef CONFIG_IOMMU_DEBUG
33int force_iommu __read_mostly = 1;
34#else
35int force_iommu __read_mostly;
36#endif
37
38/* Set this to 1 if there is a HW IOMMU in the system */
39int iommu_detected __read_mostly;
40
41/* Dummy device used for NULL arguments (normally ISA). Better would
42 be probably a smaller DMA mask, but this is bug-to-bug compatible
43 to i386. */
44struct device fallback_dev = {
45 .bus_id = "fallback device",
46 .coherent_dma_mask = DMA_32BIT_MASK,
47 .dma_mask = &fallback_dev.coherent_dma_mask,
48};
49
50void __init pci_iommu_alloc(void)
51{
52 /*
53 * The order of these functions is important for
54 * fall-back/fail-over reasons
55 */
56 detect_intel_iommu();
57
58#ifdef CONFIG_SWIOTLB
59 pci_swiotlb_init();
60#endif
61}
62
63static int __init pci_iommu_init(void)
64{
65 if (iommu_detected)
66 intel_iommu_init();
67
68 return 0;
69}
70
71/* Must execute after PCI subsystem */
72fs_initcall(pci_iommu_init);
73
74void pci_iommu_shutdown(void)
75{
76 return;
77}
78
79void __init
80iommu_dma_init(void)
81{
82 return;
83}
84
85struct dma_mapping_ops *dma_ops;
86EXPORT_SYMBOL(dma_ops);
87
88int iommu_dma_supported(struct device *dev, u64 mask)
89{
90 struct dma_mapping_ops *ops = get_dma_ops(dev);
91
92#ifdef CONFIG_PCI
93 if (mask > 0xffffffff && forbid_dac > 0) {
94 dev_info(dev, "Disallowing DAC for device\n");
95 return 0;
96 }
97#endif
98
99 if (ops->dma_supported_op)
100 return ops->dma_supported_op(dev, mask);
101
102 /* Copied from i386. Doesn't make much sense, because it will
103 only work for pci_alloc_coherent.
104 The caller just has to use GFP_DMA in this case. */
105 if (mask < DMA_24BIT_MASK)
106 return 0;
107
108 /* Tell the device to use SAC when IOMMU force is on. This
109 allows the driver to use cheaper accesses in some cases.
110
111 Problem with this is that if we overflow the IOMMU area and
112 return DAC as fallback address the device may not handle it
113 correctly.
114
115 As a special case some controllers have a 39bit address
116 mode that is as efficient as 32bit (aic79xx). Don't force
117 SAC for these. Assume all masks <= 40 bits are of this
118 type. Normally this doesn't make any difference, but gives
119 more gentle handling of IOMMU overflow. */
120 if (iommu_sac_force && (mask >= DMA_40BIT_MASK)) {
121 dev_info(dev, "Force SAC with mask %lx\n", mask);
122 return 0;
123 }
124
125 return 1;
126}
127EXPORT_SYMBOL(iommu_dma_supported);
128
129#endif