x86: merge iommu initialization parameters

we merge the iommu initialization parameters in pci-dma.c
Nice thing, that both architectures at least recognize the same
parameters.

usedac i386 parameter is marked for deprecation

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 81 insertions, 0 deletions

diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 7d3bd652c36f..48ab52d052b6 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