summaryrefslogtreecommitdiff
path: root/arch/x86/include/asm/iommu_table.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/include/asm/iommu_table.h')
-rw-r--r--arch/x86/include/asm/iommu_table.h100
1 files changed, 100 insertions, 0 deletions
diff --git a/arch/x86/include/asm/iommu_table.h b/arch/x86/include/asm/iommu_table.h
new file mode 100644
index 000000000000..f229b13a5f30
--- /dev/null
+++ b/arch/x86/include/asm/iommu_table.h
@@ -0,0 +1,100 @@
+#ifndef _ASM_X86_IOMMU_TABLE_H
+#define _ASM_X86_IOMMU_TABLE_H
+
+#include <asm/swiotlb.h>
+
+/*
+ * History lesson:
+ * The execution chain of IOMMUs in 2.6.36 looks as so:
+ *
+ * [xen-swiotlb]
+ * |
+ * +----[swiotlb *]--+
+ * / | \
+ * / | \
+ * [GART] [Calgary] [Intel VT-d]
+ * /
+ * /
+ * [AMD-Vi]
+ *
+ * *: if SWIOTLB detected 'iommu=soft'/'swiotlb=force' it would skip
+ * over the rest of IOMMUs and unconditionally initialize the SWIOTLB.
+ * Also it would surreptitiously initialize set the swiotlb=1 if there were
+ * more than 4GB and if the user did not pass in 'iommu=off'. The swiotlb
+ * flag would be turned off by all IOMMUs except the Calgary one.
+ *
+ * The IOMMU_INIT* macros allow a similar tree (or more complex if desired)
+ * to be built by defining who we depend on.
+ *
+ * And all that needs to be done is to use one of the macros in the IOMMU
+ * and the pci-dma.c will take care of the rest.
+ */
+
+struct iommu_table_entry {
+ initcall_t detect;
+ initcall_t depend;
+ void (*early_init)(void); /* No memory allocate available. */
+ void (*late_init)(void); /* Yes, can allocate memory. */
+#define IOMMU_FINISH_IF_DETECTED (1<<0)
+#define IOMMU_DETECTED (1<<1)
+ int flags;
+};
+/*
+ * Macro fills out an entry in the .iommu_table that is equivalent
+ * to the fields that 'struct iommu_table_entry' has. The entries
+ * that are put in the .iommu_table section are not put in any order
+ * hence during boot-time we will have to resort them based on
+ * dependency. */
+
+
+#define __IOMMU_INIT(_detect, _depend, _early_init, _late_init, _finish)\
+ static const struct iommu_table_entry const \
+ __iommu_entry_##_detect __used \
+ __attribute__ ((unused, __section__(".iommu_table"), \
+ aligned((sizeof(void *))))) \
+ = {_detect, _depend, _early_init, _late_init, \
+ _finish ? IOMMU_FINISH_IF_DETECTED : 0}
+/*
+ * The simplest IOMMU definition. Provide the detection routine
+ * and it will be run after the SWIOTLB and the other IOMMUs
+ * that utilize this macro. If the IOMMU is detected (ie, the
+ * detect routine returns a positive value), the other IOMMUs
+ * are also checked. You can use IOMMU_INIT_POST_FINISH if you prefer
+ * to stop detecting the other IOMMUs after yours has been detected.
+ */
+#define IOMMU_INIT_POST(_detect) \
+ __IOMMU_INIT(_detect, pci_swiotlb_detect_4gb, 0, 0, 0)
+
+#define IOMMU_INIT_POST_FINISH(detect) \
+ __IOMMU_INIT(_detect, pci_swiotlb_detect_4gb, 0, 0, 1)
+
+/*
+ * A more sophisticated version of IOMMU_INIT. This variant requires:
+ * a). A detection routine function.
+ * b). The name of the detection routine we depend on to get called
+ * before us.
+ * c). The init routine which gets called if the detection routine
+ * returns a positive value from the pci_iommu_alloc. This means
+ * no presence of a memory allocator.
+ * d). Similar to the 'init', except that this gets called from pci_iommu_init
+ * where we do have a memory allocator.
+ *
+ * The standard vs the _FINISH differs in that the _FINISH variant will
+ * continue detecting other IOMMUs in the call list after the
+ * the detection routine returns a positive number. The _FINISH will
+ * stop the execution chain. Both will still call the 'init' and
+ * 'late_init' functions if they are set.
+ */
+#define IOMMU_INIT_FINISH(_detect, _depend, _init, _late_init) \
+ __IOMMU_INIT(_detect, _depend, _init, _late_init, 1)
+
+#define IOMMU_INIT(_detect, _depend, _init, _late_init) \
+ __IOMMU_INIT(_detect, _depend, _init, _late_init, 0)
+
+void sort_iommu_table(struct iommu_table_entry *start,
+ struct iommu_table_entry *finish);
+
+void check_iommu_entries(struct iommu_table_entry *start,
+ struct iommu_table_entry *finish);
+
+#endif /* _ASM_X86_IOMMU_TABLE_H */