Commit Graph

7 Commits

Author SHA1 Message Date
David Daney
b791d1193a MIPS: Allow kernel use of LL/SC to be separate from the presence of LL/SC.
On some CPUs, it is more efficient to disable and enable interrupts in the
kernel rather than use ll/sc for atomic operations.  But if we were to set
cpu_has_llsc to false, we would break the userspace futex interface (in
asm/futex.h).

We separate the two concepts, with a new predicate kernel_uses_llsc, that
lets us disable the kernel's use of ll/sc while still allowing the futex
code to use it.

Also there were a couple of cases in bitops.h where we were using ll/sc
unconditionally even if cpu_has_llsc were false.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-09-17 20:07:50 +02:00
David Daney
fbeda19f82 MIPS: Allow CPU specific overriding of CP0 hwrena impl bits.
Some CPUs have implementation dependent rdhwr registers.  Allow them
to be enabled on a per CPU basis.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-06-17 11:06:31 +01:00
David Daney
41f0e4d041 MIPS: Allow R2 CPUs to turn off generation of 'ehb' instructions.
Some CPUs do not need ehb instructions after writing CP0 registers.
By allowing ehb generation to be overridden in
cpu-feature-overrides.h, we can save a few instructions in the TLB
handler hot paths.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-06-17 11:06:26 +01:00
Ralf Baechle
47740eb887 MIPS: Enable CLO / CLZ instructions via separate CPU property
This is useful for IDT RC32332, RC32334 and NEC VR5500 processors which do
not implement the full MIPS32 / MIPS64 architecture.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-05-14 13:50:26 +01:00
David Daney
47d979eca3 MIPS: Hook Cavium OCTEON cache init into cache.c
Follow precedent of other boards, and hook-up the CPU specific cache
init.

Signed-off-by: Tomaso Paoletti <tpaoletti@caviumnetworks.com>
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-01-11 09:57:22 +00:00
Ralf Baechle
c46b302b94 MIPS: New feature test macro cpu_has_mips_r
cpu_has_mips_r is true if a processor is MIPS32 or MIPS64, any architecture
revision.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2008-10-30 14:44:33 +00:00
Ralf Baechle
384740dc49 MIPS: Move headfiles to new location below arch/mips/include
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2008-10-11 16:18:52 +01:00