aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/kernel/pci-dma.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/pci-dma.c')
-rw-r--r--arch/x86/kernel/pci-dma.c81
1 files changed, 81 insertions, 0 deletions
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 7d3bd652c36..48ab52d052b 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -24,6 +24,18 @@ int panic_on_overflow __read_mostly = 0;
int force_iommu __read_mostly = 0;
#endif
+int iommu_merge __read_mostly = 0;
+
+int no_iommu __read_mostly;
+/* Set this to 1 if there is a HW IOMMU in the system */
+int iommu_detected __read_mostly = 0;
+
+/* This tells the BIO block layer to assume merging. Default to off
+ because we cannot guarantee merging later. */
+int iommu_bio_merge __read_mostly = 0;
+EXPORT_SYMBOL(iommu_bio_merge);
+
+
int dma_set_mask(struct device *dev, u64 mask)
{
if (!dev->dma_mask || !dma_supported(dev, mask))
@@ -105,6 +117,75 @@ void __init pci_iommu_alloc(void)
}
#endif
+/*
+ * See <Documentation/x86_64/boot-options.txt> for the iommu kernel parameter
+ * documentation.
+ */
+static __init int iommu_setup(char *p)
+{
+ iommu_merge = 1;
+
+ if (!p)
+ return -EINVAL;
+
+ while (*p) {
+ if (!strncmp(p, "off", 3))
+ no_iommu = 1;
+ /* gart_parse_options has more force support */
+ if (!strncmp(p, "force", 5))
+ force_iommu = 1;
+ if (!strncmp(p, "noforce", 7)) {
+ iommu_merge = 0;
+ force_iommu = 0;
+ }
+
+ if (!strncmp(p, "biomerge", 8)) {
+ iommu_bio_merge = 4096;
+ iommu_merge = 1;
+ force_iommu = 1;
+ }
+ if (!strncmp(p, "panic", 5))
+ panic_on_overflow = 1;
+ if (!strncmp(p, "nopanic", 7))
+ panic_on_overflow = 0;
+ if (!strncmp(p, "merge", 5)) {
+ iommu_merge = 1;
+ force_iommu = 1;
+ }
+ if (!strncmp(p, "nomerge", 7))
+ iommu_merge = 0;
+ if (!strncmp(p, "forcesac", 8))
+ iommu_sac_force = 1;
+ if (!strncmp(p, "allowdac", 8))
+ forbid_dac = 0;
+ if (!strncmp(p, "nodac", 5))
+ forbid_dac = -1;
+ if (!strncmp(p, "usedac", 6)) {
+ forbid_dac = -1;
+ return 1;
+ }
+#ifdef CONFIG_SWIOTLB
+ if (!strncmp(p, "soft", 4))
+ swiotlb = 1;
+#endif
+
+#ifdef CONFIG_GART_IOMMU
+ gart_parse_options(p);
+#endif
+
+#ifdef CONFIG_CALGARY_IOMMU
+ if (!strncmp(p, "calgary", 7))
+ use_calgary = 1;
+#endif /* CONFIG_CALGARY_IOMMU */
+
+ p += strcspn(p, ",");
+ if (*p == ',')
+ ++p;
+ }
+ return 0;
+}
+early_param("iommu", iommu_setup);
+
int dma_supported(struct device *dev, u64 mask)
{
#ifdef CONFIG_PCI