Commit Graph

14 Commits

Author SHA1 Message Date
Ralf Baechle b633648c5a MIPS: MT: Remove SMTC support
Nobody is maintaining SMTC anymore and there also seems to be no userbase.
Which is a pity - the SMTC technology primarily developed by Kevin D.
Kissell <kevink@paralogos.com> is an ingenious demonstration for the MT
ASE's power and elegance.

Based on Markos Chandras <Markos.Chandras@imgtec.com> patch
https://patchwork.linux-mips.org/patch/6719/ which while very similar did
no longer apply cleanly when I tried to merge it plus some additional
post-SMTC cleanup - SMTC was a feature as tricky to remove as it was to
merge once upon a time.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-24 00:07:01 +02:00
Ralf Baechle a809d46066 MIPS: Fix gigaton of warning building with microMIPS.
With binutils 2.24 the attempt to switch with microMIPS mode to MIPS III
mode through .set mips3 results in *lots* of warnings like

{standard input}: Assembler messages:
{standard input}:397: Warning: the 64-bit MIPS architecture does not support the `smartmips' extension

during a kernel build.  Fixed by using .set arch=r4000 instead.

This breaks support for building the kernel with binutils 2.13 which
was supported for 32 bit kernels only anyway and 2.14 which was a bad
vintage for MIPS anyway.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-03-31 18:17:12 +02:00
Jayachandran C c2377a42cd MIPS: Move definition of SMP processor id register to header file
The definition of the CP0 register used to save the smp processor
id is repicated in many files, move them all to thread_info.h.

Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5708/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-10-29 21:23:51 +01:00
David Daney 8dfdd02a4c MIPS: Don't save/restore OCTEON wide multiplier state on syscalls.
The ABI allows these to be clobbered on syscalls, so only save and
restore the multiplier state when the temporary registers need to be
preserved.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: David Daney <david.daney@cavium.com>
Patchwork: https://patchwork.linux-mips.org/patch/5540/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-07-01 15:10:56 +02:00
Steven J. Hill 2a0b24f56c MIPS: microMIPS: Add support for exception handling.
All exceptions must be taken in microMIPS mode, never in classic
MIPS mode or the kernel falls apart. A few NOP instructions are
used to maintain the correct alignment of microMIPS versions of
the exception vectors.

Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
2013-05-09 17:55:18 +02:00
Ralf Baechle 7034228792 MIPS: Whitespace cleanup.
Having received another series of whitespace patches I decided to do this
once and for all rather than dealing with this kind of patches trickling
in forever.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-02-01 10:00:22 +01:00
David Daney d968275921 MIPS: Don't clobber CP0_STATUS value for CONFIG_MIPS_MT_SMTC
Reported-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Signed-off-by: David Daney <david.daney@cavium.com>
Patchwork: https://patchwork.linux-mips.org/patch/2753/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-09-21 17:54:02 +02:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Wu Zhangjin b197b62866 MIPS: Loongson-2F: Use CONFIG_CPU_JUMP_WORKAROUNDS to control workarounds.
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips <linux-mips@linux-mips.org>
Patchwork: http://patchwork.linux-mips.org/patch/1106/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2010-04-30 20:52:58 +01:00
Wu Zhangjin f1df323924 MIPS: Loongson-2F: Flush the branch target history in BTB and RAS
As per chapter 15 "Errata: Issue of Out-of-order in loongson"[1] to work
around the Loongson 2F erratum we need to do:

"When switching from user mode to kernel mode, you should flush the
branch target history such as BTB and RAS."

[1] Chinese version: http://www.loongson.cn/uploadfile/file/200808211
[2] English version of chapter 15:
    http://groups.google.com.hk/group/loongson-dev/msg/e0d2e220958f10a6?dmode=source

Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Patchwork: http://patchwork.linux-mips.org/patch/1066/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2010-04-12 17:26:15 +01:00
David Daney 82622284dd MIPS: Put PGD in C0_CONTEXT for 64-bit R2 processors.
Processors that support the mips64r2 ISA can in four instructions
convert a shifted PGD pointer stored in the upper bits of c0_context
into a usable pointer.  By doing this we save a memory load and
associated potential cache miss in the TLB exception handlers.

Since the upper bits of c0_context were holding the CPU number, we
move this to the upper bits of c0_xcontext which doesn't have enough
bits to hold the PGD pointer, but has plenty for the CPU number.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-12-17 01:57:01 +00:00
David Daney 362e696428 MIPS: Reorder operations in stackframe.h for better scheduling
Reorder PT ops to avoid pipeline stalls.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-12-17 01:56:57 +00:00
David Daney 2a219b0eaa MIPS: Cavium OCTEON multiplier state preservation.
For OCTEON, implement a save and restore of the multiplier state
across context switches.

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 09:57:24 +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