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authorAlex Williamson <alex.williamson@hp.com>2005-09-06 11:20:49 -0600
committerTony Luck <tony.luck@intel.com>2005-09-14 16:22:11 -0700
commit0b9afede3d9c66fef06f1d5ef5ff15c4b97730fc (patch)
tree95f55e1219eed9c3fd2458ddbf960307c631114e /arch/ia64/lib
parent1619cca2921f6927f4240e03f413d4165c7002fc (diff)
downloadop-kernel-dev-0b9afede3d9c66fef06f1d5ef5ff15c4b97730fc.zip
op-kernel-dev-0b9afede3d9c66fef06f1d5ef5ff15c4b97730fc.tar.gz
[IA64] more robust zx1/sx1000 machvec support
Machine vector selection has always been a bit of a hack given how early in system boot it needs to be done. Services like ACPI namespace are not available and there are non-trivial problems to moving them to early boot. However, there's no reason we can't change to a different machvec later in boot when the services we need are available. By adding a entry point for later initialization of the swiotlb, we can add an error path for the hpzx1 machevec initialization and fall back to the DIG machine vector if IOMMU hardware isn't found in the system. Since ia64 uses 4GB for zone DMA (no ISA support), it's trivial to allocate a contiguous range from the slab for bounce buffer usage. Signed-off-by: Alex Williamson <alex.williamson@hp.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
Diffstat (limited to 'arch/ia64/lib')
-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 dbc0b3e..875b0c1 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)
{
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