Eric Lee / linux-smarc-t335x-v3.2

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Commit b81ea27b2329bf44b30c427800954f845896d476

Authored by Ian Campbell
Committed by Ingo Molnar
1 parent e08e1f7adb
Exists in master and in 4 other branches v3.2_AM335xPSP_04.06.00.11, v3.2_NEWT335xPSP_04.06.00.11, v3.2_SBC_SMARTMEN, v3.2_SMARCT335xPSP_04.06.00.11

swiotlb: add arch hook to force mapping 

Impact: generalize the sw-IOTLB range checks

Some architectures require special rules to determine whether a range
needs mapping or not.  This adds a weak function for architectures to
override.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Showing 2 changed files with 15 additions and 2 deletions Side-by-side Diff

include/linux/swiotlb.h
Diff comments   View file @ b81ea27
... ... @@ -30,6 +30,8 @@
30 30 extern dma_addr_t swiotlb_phys_to_bus(phys_addr_t address);
31 31 extern phys_addr_t swiotlb_bus_to_phys(dma_addr_t address);
32 32  
  33 +extern int swiotlb_arch_range_needs_mapping(void *ptr, size_t size);
  34 +
33 35 extern void
34 36 *swiotlb_alloc_coherent(struct device *hwdev, size_t size,
35 37 dma_addr_t *dma_handle, gfp_t flags);
... ... @@ -145,6 +145,11 @@
145 145 return phys_to_virt(swiotlb_bus_to_phys(address));
146 146 }
147 147  
  148 +int __weak swiotlb_arch_range_needs_mapping(void *ptr, size_t size)
  149 +{
  150 + return 0;
  151 +}
  152 +
148 153 /*
149 154 * Statically reserve bounce buffer space and initialize bounce buffer data
150 155 * structures for the software IO TLB used to implement the DMA API.
... ... @@ -297,6 +302,11 @@
297 302 return !is_buffer_dma_capable(dma_get_mask(hwdev), addr, size);
298 303 }
299 304  
  305 +static inline int range_needs_mapping(void *ptr, size_t size)
  306 +{
  307 + return swiotlb_force || swiotlb_arch_range_needs_mapping(ptr, size);
  308 +}
  309 +
300 310 static int is_swiotlb_buffer(char *addr)
301 311 {
302 312 return addr >= io_tlb_start && addr < io_tlb_end;
... ... @@ -585,7 +595,8 @@
585 595 * we can safely return the device addr and not worry about bounce
586 596 * buffering it.
587 597 */
588   - if (!address_needs_mapping(hwdev, dev_addr, size) && !swiotlb_force)
  598 + if (!address_needs_mapping(hwdev, dev_addr, size) &&
  599 + !range_needs_mapping(ptr, size))
589 600 return dev_addr;
590 601  
591 602 /*
... ... @@ -745,7 +756,7 @@
745 756 for_each_sg(sgl, sg, nelems, i) {
746 757 addr = SG_ENT_VIRT_ADDRESS(sg);
747 758 dev_addr = swiotlb_virt_to_bus(addr);
748   - if (swiotlb_force ||
  759 + if (range_needs_mapping(sg_virt(sg), sg->length) ||
749 760 address_needs_mapping(hwdev, dev_addr, sg->length)) {
750 761 void *map = map_single(hwdev, addr, sg->length, dir);
751 762 if (!map) {