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Diffstat (limited to 'arch/x86_64/kernel/pci-nommu.c')
-rw-r--r--arch/x86_64/kernel/pci-nommu.c94
1 files changed, 94 insertions, 0 deletions
diff --git a/arch/x86_64/kernel/pci-nommu.c b/arch/x86_64/kernel/pci-nommu.c
new file mode 100644
index 00000000000..67d90b89af0
--- /dev/null
+++ b/arch/x86_64/kernel/pci-nommu.c
@@ -0,0 +1,94 @@
+/* Fallback functions when the main IOMMU code is not compiled in. This
+ code is roughly equivalent to i386. */
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/string.h>
+#include <asm/proto.h>
+#include <asm/processor.h>
+
+int iommu_merge = 0;
+EXPORT_SYMBOL(iommu_merge);
+
+dma_addr_t bad_dma_address;
+EXPORT_SYMBOL(bad_dma_address);
+
+int iommu_bio_merge = 0;
+EXPORT_SYMBOL(iommu_bio_merge);
+
+int iommu_sac_force = 0;
+EXPORT_SYMBOL(iommu_sac_force);
+
+/*
+ * Dummy IO MMU functions
+ */
+
+void *dma_alloc_coherent(struct device *hwdev, size_t size,
+ dma_addr_t *dma_handle, unsigned gfp)
+{
+ void *ret;
+ u64 mask;
+ int order = get_order(size);
+
+ if (hwdev)
+ mask = hwdev->coherent_dma_mask & *hwdev->dma_mask;
+ else
+ mask = 0xffffffff;
+ for (;;) {
+ ret = (void *)__get_free_pages(gfp, order);
+ if (ret == NULL)
+ return NULL;
+ *dma_handle = virt_to_bus(ret);
+ if ((*dma_handle & ~mask) == 0)
+ break;
+ free_pages((unsigned long)ret, order);
+ if (gfp & GFP_DMA)
+ return NULL;
+ gfp |= GFP_DMA;
+ }
+
+ memset(ret, 0, size);
+ return ret;
+}
+EXPORT_SYMBOL(dma_alloc_coherent);
+
+void dma_free_coherent(struct device *hwdev, size_t size,
+ void *vaddr, dma_addr_t dma_handle)
+{
+ free_pages((unsigned long)vaddr, get_order(size));
+}
+EXPORT_SYMBOL(dma_free_coherent);
+
+int dma_supported(struct device *hwdev, u64 mask)
+{
+ /*
+ * we fall back to GFP_DMA when the mask isn't all 1s,
+ * so we can't guarantee allocations that must be
+ * within a tighter range than GFP_DMA..
+ * RED-PEN this won't work for pci_map_single. Caller has to
+ * use GFP_DMA in the first place.
+ */
+ if (mask < 0x00ffffff)
+ return 0;
+
+ return 1;
+}
+EXPORT_SYMBOL(dma_supported);
+
+int dma_get_cache_alignment(void)
+{
+ return boot_cpu_data.x86_clflush_size;
+}
+EXPORT_SYMBOL(dma_get_cache_alignment);
+
+static int __init check_ram(void)
+{
+ if (end_pfn >= 0xffffffff>>PAGE_SHIFT) {
+ printk(
+ KERN_ERR "WARNING more than 4GB of memory but IOMMU not compiled in.\n"
+ KERN_ERR "WARNING 32bit PCI may malfunction.\n");
+ }
+ return 0;
+}
+__initcall(check_ram);
+