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+#
+# MN10300 CPU cache options
+#
+
+choice
+ prompt "CPU Caching mode"
+ default MN10300_CACHE_WBACK
+ help
+ This option determines the caching mode for the kernel.
+
+ Write-Back caching mode involves the all reads and writes causing
+ the affected cacheline to be read into the cache first before being
+ operated upon. Memory is not then updated by a write until the cache
+ is filled and a cacheline needs to be displaced from the cache to
+ make room. Only at that point is it written back.
+
+ Write-Through caching only fetches cachelines from memory on a
+ read. Writes always get written directly to memory. If the affected
+ cacheline is also in cache, it will be updated too.
+
+ The final option is to turn of caching entirely.
+
+config MN10300_CACHE_WBACK
+ bool "Write-Back"
+ help
+ The dcache operates in delayed write-back mode. It must be manually
+ flushed if writes are made that subsequently need to be executed or
+ to be DMA'd by a device.
+
+config MN10300_CACHE_WTHRU
+ bool "Write-Through"
+ help
+ The dcache operates in immediate write-through mode. Writes are
+ committed to RAM immediately in addition to being stored in the
+ cache. This means that the written data is immediately available for
+ execution or DMA.
+
+ This is not available for use with an SMP kernel if cache flushing
+ and invalidation by automatic purge register is not selected.
+
+config MN10300_CACHE_DISABLED
+ bool "Disabled"
+ help
+ The icache and dcache are disabled.
+
+endchoice
+
+config MN10300_CACHE_ENABLED
+ def_bool y if !MN10300_CACHE_DISABLED
+
+
+choice
+ prompt "CPU cache flush/invalidate method"
+ default MN10300_CACHE_MANAGE_BY_TAG if !AM34_2
+ default MN10300_CACHE_MANAGE_BY_REG if AM34_2
+ depends on MN10300_CACHE_ENABLED
+ help
+ This determines the method by which CPU cache flushing and
+ invalidation is performed.
+
+config MN10300_CACHE_MANAGE_BY_TAG
+ bool "Use the cache tag registers directly"
+ depends on !(SMP && MN10300_CACHE_WTHRU)
+
+config MN10300_CACHE_MANAGE_BY_REG
+ bool "Flush areas by way of automatic purge registers (AM34 only)"
+ depends on AM34_2
+
+endchoice
+
+config MN10300_CACHE_INV_BY_TAG
+ def_bool y if MN10300_CACHE_MANAGE_BY_TAG && MN10300_CACHE_ENABLED
+
+config MN10300_CACHE_INV_BY_REG
+ def_bool y if MN10300_CACHE_MANAGE_BY_REG && MN10300_CACHE_ENABLED
+
+config MN10300_CACHE_FLUSH_BY_TAG
+ def_bool y if MN10300_CACHE_MANAGE_BY_TAG && MN10300_CACHE_WBACK
+
+config MN10300_CACHE_FLUSH_BY_REG
+ def_bool y if MN10300_CACHE_MANAGE_BY_REG && MN10300_CACHE_WBACK
+
+
+config MN10300_HAS_CACHE_SNOOP
+ def_bool n
+
+config MN10300_CACHE_SNOOP
+ bool "Use CPU Cache Snooping"
+ depends on MN10300_CACHE_ENABLED && MN10300_HAS_CACHE_SNOOP
+ default y
+
+config MN10300_CACHE_FLUSH_ICACHE
+ def_bool y if MN10300_CACHE_WBACK && !MN10300_CACHE_SNOOP
+ help
+ Set if we need the dcache flushing before the icache is invalidated.
+
+config MN10300_CACHE_INV_ICACHE
+ def_bool y if MN10300_CACHE_WTHRU && !MN10300_CACHE_SNOOP
+ help
+ Set if we need the icache to be invalidated, even if the dcache is in
+ write-through mode and doesn't need flushing.
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