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-rw-r--r--arch/ia64/lib/swiotlb.c102
1 files changed, 102 insertions, 0 deletions
diff --git a/arch/ia64/lib/swiotlb.c b/arch/ia64/lib/swiotlb.c
index dbc0b3e449c5..875b0c16250c 100644
--- a/arch/ia64/lib/swiotlb.c
+++ b/arch/ia64/lib/swiotlb.c
@@ -49,6 +49,15 @@
*/
#define IO_TLB_SHIFT 11
+#define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT))
+
+/*
+ * Minimum IO TLB size to bother booting with. Systems with mainly
+ * 64bit capable cards will only lightly use the swiotlb. If we can't
+ * allocate a contiguous 1MB, we're probably in trouble anyway.
+ */
+#define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)
+
int swiotlb_force;
/*
@@ -154,6 +163,99 @@ swiotlb_init (void)
swiotlb_init_with_default_size(64 * (1<<20)); /* default to 64MB */
}
+/*
+ * Systems with larger DMA zones (those that don't support ISA) can
+ * initialize the swiotlb later using the slab allocator if needed.
+ * This should be just like above, but with some error catching.
+ */
+int
+swiotlb_late_init_with_default_size (size_t default_size)
+{
+ unsigned long i, req_nslabs = io_tlb_nslabs;
+ unsigned int order;
+
+ if (!io_tlb_nslabs) {
+ io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
+ io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
+ }
+
+ /*
+ * Get IO TLB memory from the low pages
+ */
+ order = get_order(io_tlb_nslabs * (1 << IO_TLB_SHIFT));
+ io_tlb_nslabs = SLABS_PER_PAGE << order;
+
+ while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) {
+ io_tlb_start = (char *)__get_free_pages(GFP_DMA | __GFP_NOWARN,
+ order);
+ if (io_tlb_start)
+ break;
+ order--;
+ }
+
+ if (!io_tlb_start)
+ goto cleanup1;
+
+ if (order != get_order(io_tlb_nslabs * (1 << IO_TLB_SHIFT))) {
+ printk(KERN_WARNING "Warning: only able to allocate %ld MB "
+ "for software IO TLB\n", (PAGE_SIZE << order) >> 20);
+ io_tlb_nslabs = SLABS_PER_PAGE << order;
+ }
+ io_tlb_end = io_tlb_start + io_tlb_nslabs * (1 << IO_TLB_SHIFT);
+ memset(io_tlb_start, 0, io_tlb_nslabs * (1 << IO_TLB_SHIFT));
+
+ /*
+ * Allocate and initialize the free list array. This array is used
+ * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
+ * between io_tlb_start and io_tlb_end.
+ */
+ io_tlb_list = (unsigned int *)__get_free_pages(GFP_KERNEL,
+ get_order(io_tlb_nslabs * sizeof(int)));
+ if (!io_tlb_list)
+ goto cleanup2;
+
+ for (i = 0; i < io_tlb_nslabs; i++)
+ io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
+ io_tlb_index = 0;
+
+ io_tlb_orig_addr = (unsigned char **)__get_free_pages(GFP_KERNEL,
+ get_order(io_tlb_nslabs * sizeof(char *)));
+ if (!io_tlb_orig_addr)
+ goto cleanup3;
+
+ memset(io_tlb_orig_addr, 0, io_tlb_nslabs * sizeof(char *));
+
+ /*
+ * Get the overflow emergency buffer
+ */
+ io_tlb_overflow_buffer = (void *)__get_free_pages(GFP_DMA,
+ get_order(io_tlb_overflow));
+ if (!io_tlb_overflow_buffer)
+ goto cleanup4;
+
+ printk(KERN_INFO "Placing %ldMB software IO TLB between 0x%lx - "
+ "0x%lx\n", (io_tlb_nslabs * (1 << IO_TLB_SHIFT)) >> 20,
+ virt_to_phys(io_tlb_start), virt_to_phys(io_tlb_end));
+
+ return 0;
+
+cleanup4:
+ free_pages((unsigned long)io_tlb_orig_addr, get_order(io_tlb_nslabs *
+ sizeof(char *)));
+ io_tlb_orig_addr = NULL;
+cleanup3:
+ free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs *
+ sizeof(int)));
+ io_tlb_list = NULL;
+ io_tlb_end = NULL;
+cleanup2:
+ free_pages((unsigned long)io_tlb_start, order);
+ io_tlb_start = NULL;
+cleanup1:
+ io_tlb_nslabs = req_nslabs;
+ return -ENOMEM;
+}
+
static inline int
address_needs_mapping(struct device *hwdev, dma_addr_t addr)
{