on R5000/Rm52xx machines:
- Add a new global variable mips_cache_virtual_alias in mips/cache.c,
which indicates that VIPT cache on the CPU could cause virtual alias
and software support is required to handle it. (i.e. no VCED/VCEI)
- Add several cache flush/invalidate ops around KSEG0 access which
might cause virtual alias if mips_cache_virtual_alias is true.
(note checking mips_sdcache_line_size isn't valid for R5000/Rm52xx
because only R4000/R4400 with L2 cache have VCED/VCEI)
- Remove a global variable mips_sdcache_forceinv, which is now superseded
by new mips_cache_virtual_alias.
While here, also change some R4000/R4400 cache ops:
- Don't override mips_cache_alias_mask and mips_cache_prefer_mask with
values based on MIPS3_MAX_PCACHE_SIZE for R4000/R4400 with L2 cache
because it's still worth to reduce VCED/VCEI.
- Flush dcache in pmap_zero_page(9) unconditionally on all MIPS_HAS_R4K_MMU
CPUs and remove cache flush code from cpu_lwp_fork() in vm_machdep.c.
Thanks to Markus W Kilbinger for testing patches on port-cobalt/port-mips.
XXX This fix is just a workaround because it doesn't handle all possible
XXX virtual aliases. As discussed on port-mips, maybe the real fix
XXX for virtual alias is to change MI UVM to adapt it to VIPT cache.
XXX (all VA mappings against the same PA must have the same VAC index etc.)
to select the maximum segment size for each bus_dmamap_load (up to the maxsegsz
supplied to bus_dmamap_create). dm_maxsegsz is reset to the value supplied to
bus_dmamap_create when the dmamap is unloaded.
that tells pmap_zero_page() and pmap_copy_page() to unconditionally invalidate
pages for r5k-class CPUs with secondary cache.
This behavior must be explicitly enabled by setting mips_sdcache_forceinv to 1.
This is the last bit of a patch that has been kicked around since 2000 between
rafal@, tsutsui@, and myself.
(should fix build problems w/o COMPAT_16 reported by Markus W Kilbinger
per PR port-mips/29041 and by Havard Eidnes)
-further shuffle COMPAT_* conditionals to allow COMPAT_ULTRIX
w/o COMPAT_16
to four (adding size and direction).
In order for topdown uvm to be an option on ports using PMAP_PREFER,
they will need to "prefer" lower addresses if topdown is being used.
Additionally, at least one port also needs to know the size.
Originally written by rafal@ back in April 2003. Field-tested by many
people since.
(I am not committing the pmap hack at this time; although pmap changes are
necessary to fully address the r5k panic/coma problems, the implementation
needs further thought)
CSR separately (and now from the correctly sized __fpregset_t). The
FP CSR is copied separately to avoid endianness/alignment issues.
Part of fix for PR port-mips/25942. Thanks to Christos Zoulas and
Klaus Klein for help with debugging this.
tsutsui