x86/efi: Enforce CONFIG_RELOCATABLE for EFI boot stub
[linux/fpc-iii.git] / arch / x86 / include / asm / iommu_table.h
blobf42a04735a0a66c7f15cdc8640308861902c753d
1 #ifndef _ASM_X86_IOMMU_TABLE_H
2 #define _ASM_X86_IOMMU_TABLE_H
4 #include <asm/swiotlb.h>
6 /*
7 * History lesson:
8 * The execution chain of IOMMUs in 2.6.36 looks as so:
10 * [xen-swiotlb]
11 * |
12 * +----[swiotlb *]--+
13 * / | \
14 * / | \
15 * [GART] [Calgary] [Intel VT-d]
16 * /
17 * /
18 * [AMD-Vi]
20 * *: if SWIOTLB detected 'iommu=soft'/'swiotlb=force' it would skip
21 * over the rest of IOMMUs and unconditionally initialize the SWIOTLB.
22 * Also it would surreptitiously initialize set the swiotlb=1 if there were
23 * more than 4GB and if the user did not pass in 'iommu=off'. The swiotlb
24 * flag would be turned off by all IOMMUs except the Calgary one.
26 * The IOMMU_INIT* macros allow a similar tree (or more complex if desired)
27 * to be built by defining who we depend on.
29 * And all that needs to be done is to use one of the macros in the IOMMU
30 * and the pci-dma.c will take care of the rest.
33 struct iommu_table_entry {
34 initcall_t detect;
35 initcall_t depend;
36 void (*early_init)(void); /* No memory allocate available. */
37 void (*late_init)(void); /* Yes, can allocate memory. */
38 #define IOMMU_FINISH_IF_DETECTED (1<<0)
39 #define IOMMU_DETECTED (1<<1)
40 int flags;
43 * Macro fills out an entry in the .iommu_table that is equivalent
44 * to the fields that 'struct iommu_table_entry' has. The entries
45 * that are put in the .iommu_table section are not put in any order
46 * hence during boot-time we will have to resort them based on
47 * dependency. */
50 #define __IOMMU_INIT(_detect, _depend, _early_init, _late_init, _finish)\
51 static const struct iommu_table_entry \
52 __iommu_entry_##_detect __used \
53 __attribute__ ((unused, __section__(".iommu_table"), \
54 aligned((sizeof(void *))))) \
55 = {_detect, _depend, _early_init, _late_init, \
56 _finish ? IOMMU_FINISH_IF_DETECTED : 0}
58 * The simplest IOMMU definition. Provide the detection routine
59 * and it will be run after the SWIOTLB and the other IOMMUs
60 * that utilize this macro. If the IOMMU is detected (ie, the
61 * detect routine returns a positive value), the other IOMMUs
62 * are also checked. You can use IOMMU_INIT_POST_FINISH if you prefer
63 * to stop detecting the other IOMMUs after yours has been detected.
65 #define IOMMU_INIT_POST(_detect) \
66 __IOMMU_INIT(_detect, pci_swiotlb_detect_4gb, NULL, NULL, 0)
68 #define IOMMU_INIT_POST_FINISH(detect) \
69 __IOMMU_INIT(_detect, pci_swiotlb_detect_4gb, NULL, NULL, 1)
72 * A more sophisticated version of IOMMU_INIT. This variant requires:
73 * a). A detection routine function.
74 * b). The name of the detection routine we depend on to get called
75 * before us.
76 * c). The init routine which gets called if the detection routine
77 * returns a positive value from the pci_iommu_alloc. This means
78 * no presence of a memory allocator.
79 * d). Similar to the 'init', except that this gets called from pci_iommu_init
80 * where we do have a memory allocator.
82 * The standard vs the _FINISH differs in that the _FINISH variant will
83 * continue detecting other IOMMUs in the call list after the
84 * the detection routine returns a positive number. The _FINISH will
85 * stop the execution chain. Both will still call the 'init' and
86 * 'late_init' functions if they are set.
88 #define IOMMU_INIT_FINISH(_detect, _depend, _init, _late_init) \
89 __IOMMU_INIT(_detect, _depend, _init, _late_init, 1)
91 #define IOMMU_INIT(_detect, _depend, _init, _late_init) \
92 __IOMMU_INIT(_detect, _depend, _init, _late_init, 0)
94 void sort_iommu_table(struct iommu_table_entry *start,
95 struct iommu_table_entry *finish);
97 void check_iommu_entries(struct iommu_table_entry *start,
98 struct iommu_table_entry *finish);
100 #endif /* _ASM_X86_IOMMU_TABLE_H */