sh: Disable 4kB pages on extended mode TLB.

4kB pages are unstable on extended mode TLB, it's recommended
that TLB compat mode be used when using a 4kB PAGE_SIZE. Set
the default for extended mode to 8kB.

This should have negligible impact, as other than the extra swap
cache entry bits, there's no reason to use the extended mode TLB
with 4kB pages.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

arch/sh/mm/Kconfig

@@ -336,25 +336,27 @@ config ARCH_MEMORY_PROBE
 
 choice
 	prompt "Kernel page size"
+	default PAGE_SIZE_8KB if X2TLB
 	default PAGE_SIZE_4KB
 
 config PAGE_SIZE_4KB
 	bool "4kB"
+	depends on !X2TLB
 	help
 	  This is the default page size used by all SuperH CPUs.
 
 config PAGE_SIZE_8KB
 	bool "8kB"
-	depends on EXPERIMENTAL && X2TLB
+	depends on X2TLB
 	help
 	  This enables 8kB pages as supported by SH-X2 and later MMUs.
 
 config PAGE_SIZE_64KB
 	bool "64kB"
-	depends on EXPERIMENTAL && CPU_SH4
+	depends on CPU_SH4
 	help
 	  This enables support for 64kB pages, possible on all SH-4
-	  CPUs and later. Highly experimental, not recommended.
+	  CPUs and later.
 
 endchoice