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author | Bernd Schmidt <bernds_cb1@t-online.de> | 2009-01-07 23:14:38 +0800 |
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committer | Bryan Wu <cooloney@kernel.org> | 2009-01-07 23:14:38 +0800 |
commit | dbdf20db537a5369c65330f878ad4905020a8bfa (patch) | |
tree | c7fa553755e2d75a6e98d3f32fbe41fab9f72609 /arch/blackfin/mm | |
parent | 6651ece9e257302ee695ee76e69a4427f7033235 (diff) | |
download | lwn-dbdf20db537a5369c65330f878ad4905020a8bfa.tar.gz lwn-dbdf20db537a5369c65330f878ad4905020a8bfa.zip |
Blackfin arch: Faster C implementation of no-MPU CPLB handler
This is a mixture ofcMichael McTernan's patch and the existing cplb-mpu code.
We ditch the old cplb-nompu implementation, which is a good example of
why a good algorithm in a HLL is preferrable to a bad algorithm written in
assembly. Rather than try to construct a table of all posible CPLBs and
search it, we just create a (smaller) table of memory regions and
their attributes. Some of the data structures are now unified for both
the mpu and nompu cases. A lot of needless complexity in cplbinit.c is
removed.
Further optimizations:
* compile cplbmgr.c with a lot of -ffixed-reg options, and omit saving
these registers on the stack when entering a CPLB exception.
* lose cli/nop/nop/sti sequences for some workarounds - these don't
* make
sense in an exception context
Additional code unification should be possible after this.
[Mike Frysinger <vapier.adi@gmail.com>:
- convert CPP if statements to C if statements
- remove redundant statements
- use a do...while loop rather than a for loop to get slightly better
optimization and to avoid gcc "may be used uninitialized" warnings ...
we know that the [id]cplb_nr_bounds variables will never be 0, so this
is OK
- the no-mpu code was the last user of MAX_MEM_SIZE and with that rewritten,
we can punt it
- add some BUG_ON() checks to make sure we dont overflow the small
cplb_bounds array
- add i/d cplb entries for the bootrom because there is functions/data in
there we want to access
- we do not need a NULL trailing entry as any time we access the bounds
arrays, we use the nr_bounds variable
]
Signed-off-by: Michael McTernan <mmcternan@airvana.com>
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Diffstat (limited to 'arch/blackfin/mm')
-rw-r--r-- | arch/blackfin/mm/init.c | 10 |
1 files changed, 0 insertions, 10 deletions
diff --git a/arch/blackfin/mm/init.c b/arch/blackfin/mm/init.c index 57d306b9c56d..d0532b72bba5 100644 --- a/arch/blackfin/mm/init.c +++ b/arch/blackfin/mm/init.c @@ -119,16 +119,6 @@ asmlinkage void init_pda(void) cpu_pda[cpu].ex_stack = exception_stack[cpu + 1]; -#ifdef CONFIG_MPU -#else - cpu_pda[cpu].ipdt = ipdt_tables[cpu]; - cpu_pda[cpu].dpdt = dpdt_tables[cpu]; -#ifdef CONFIG_CPLB_INFO - cpu_pda[cpu].ipdt_swapcount = ipdt_swapcount_tables[cpu]; - cpu_pda[cpu].dpdt_swapcount = dpdt_swapcount_tables[cpu]; -#endif -#endif - #ifdef CONFIG_SMP cpu_pda[cpu].imask = 0x1f; #endif |