+config DMA_CACHE_RWFO
+ bool "Enable read/write for ownership DMA cache maintenance"
+ depends on CPU_V6 && SMP
+ default y
+ help
+ The Snoop Control Unit on ARM11MPCore does not detect the
+ cache maintenance operations and the dma_{map,unmap}_area()
+ functions may leave stale cache entries on other CPUs. By
+ enabling this option, Read or Write For Ownership in the ARMv6
+ DMA cache maintenance functions is performed. These LDR/STR
+ instructions change the cache line state to shared or modified
+ so that the cache operation has the desired effect.
+
+ Note that the workaround is only valid on processors that do
+ not perform speculative loads into the D-cache. For such
+ processors, if cache maintenance operations are not broadcast
+ in hardware, other workarounds are needed (e.g. cache
+ maintenance broadcasting in software via FIQ).
+