Re: [linuxsh-dev] PCMCIA patch & question

[NIIBE Y. <gn...@ch...>]

Have tested on SolutionEngine.  More changes are needed to save PR register
in call_dpf in entry.S.

Greg Banks wrote:
 >    Is _PAGE_HW_SHARED right for kernel-only mappings?  I'm not sure
 > of the implications...

This is needed because we share the kernel mapping.  SuperH's MMU SH-bit
means that it doesn't look ASID on TLB comparison, when it is 1.

With old implementation, all the processes have PGD table entries for
kernel mapping, and we keep the kernel mapping entries same with
set_pgdir.  However, as SuperH has SH-bit, it's a kind of waste of 
memory and CPU cycles.
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