diff options
Diffstat (limited to 'arch/ia64/lib/swiotlb.c')
| -rw-r--r-- | arch/ia64/lib/swiotlb.c | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/arch/ia64/lib/swiotlb.c b/arch/ia64/lib/swiotlb.c index a604efc7f6c..48e5ff26eb1 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) { |