2010-10-28 00:28:41 +08:00
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#
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# MN10300 CPU cache options
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#
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choice
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prompt "CPU Caching mode"
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default MN10300_CACHE_WBACK
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help
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This option determines the caching mode for the kernel.
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Write-Back caching mode involves the all reads and writes causing
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the affected cacheline to be read into the cache first before being
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operated upon. Memory is not then updated by a write until the cache
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is filled and a cacheline needs to be displaced from the cache to
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make room. Only at that point is it written back.
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Write-Through caching only fetches cachelines from memory on a
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read. Writes always get written directly to memory. If the affected
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cacheline is also in cache, it will be updated too.
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The final option is to turn of caching entirely.
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config MN10300_CACHE_WBACK
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bool "Write-Back"
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config MN10300_CACHE_WTHRU
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bool "Write-Through"
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config MN10300_CACHE_DISABLED
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bool "Disabled"
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endchoice
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2010-10-28 00:28:42 +08:00
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config MN10300_CACHE_ENABLED
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def_bool y if !MN10300_CACHE_DISABLED
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