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* MIPS: bitops.h: Avoid inline asm for constant FLSMaciej W. Rozycki2015-04-081-3/+4
| | | | | | | | | | | | | | | | GCC is smart enough to substitute the final result for FLS calculations as implemented in the fallback C code we have in `__fls' and `fls' applied to constant values. The presence of inline asm defeats the compiler though, forcing it to emit extraneous CLZ/DCLZ calculation for processors that support these instructions. Use `__builtin_constant_p' then to avoid inline asm altogether for constants. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9681/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: asm: bitops: Update ISA constraints for MIPS R6 supportMarkos Chandras2015-02-171-15/+15
| | | | | | | | MIPS R6 changed the opcodes for LL/SC instructions so we need to set the correct ISA level. Cc: Matthew Fortune <Matthew.Fortune@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
* MIPS: asm: Rename GCC_OFF12_ASM to GCC_OFF_SMALL_ASMMarkos Chandras2015-02-171-17/+17
| | | | | | | | | The GCC_OFF12_ASM macro is used for 12-bit immediate constrains but we will also use it for 9-bit constrains on MIPS R6 so we rename it to something more appropriate. Cc: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
* MIPS: Fix microMIPS LL/SC immediate offsetsMaciej W. Rozycki2014-11-241-17/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the microMIPS encoding some memory access instructions have their immediate offset reduced to 12 bits only. That does not match the GCC `R' constraint we use in some places to satisfy the requirement, resulting in build failures like this: {standard input}: Assembler messages: {standard input}:720: Error: macro used $at after ".set noat" {standard input}:720: Warning: macro instruction expanded into multiple instructions Fix the problem by defining a macro, `GCC_OFF12_ASM', that expands to the right constraint depending on whether microMIPS or standard MIPS code is produced. Also apply the fix to where `m' is used as in the worst case this change does nothing, e.g. where the pointer was already in a register such as a function argument and no further offset was requested, and in the best case it avoids an extraneous sequence of up to two instructions to load the high 20 bits of the address in the LL/SC loop. This reduces the risk of lock contention that is the higher the more instructions there are in the critical section between LL and SC. Strictly speaking we could just bulk-replace `R' with `ZC' as the latter constraint adjusts automatically depending on the ISA selected. However it was only introduced with GCC 4.9 and we keep supporing older compilers for the standard MIPS configuration, hence the slightly more complicated approach I chose. The choice of a zero-argument function-like rather than an object-like macro was made so that it does not look like a function call taking the C expression used for the constraint as an argument. This is so as not to confuse the reader or formatting checkers like `checkpatch.pl' and follows previous practice. Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com> Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/8482/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: asm/bitops.h: Guard CLZ with `.set mips32'Maciej W. Rozycki2014-07-301-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | This fixes: {standard input}: Assembler messages: {standard input}:145: Error: opcode not supported on this processor: vr5000 (mips4) `clz $2,$2' {standard input}:920: Error: opcode not supported on this processor: vr5000 (mips4) `clz $7,$9' {standard input}:1797: Error: opcode not supported on this processor: vr5000 (mips4) `clz $7,$7' {standard input}:1851: Error: opcode not supported on this processor: vr5000 (mips4) `clz $7,$7' {standard input}:2831: Error: opcode not supported on this processor: vr5000 (mips4) `clz $7,$7' {standard input}:4209: Error: opcode not supported on this processor: vr5000 (mips4) `clz $7,$7' {standard input}:4329: Error: opcode not supported on this processor: vr5000 (mips4) `clz $2,$2' make[2]: *** [arch/mips/mm/tlbex.o] Error 1 which triggered due to a regression causing the file to be built with `-march=r5000' rather than `-march=sb1', fixed separately. Nevertheless the error should not happen, the other uses of CLZ are appropriately guarded. This change copies the arrangement from one of those other places. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7222/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* arch,mips: Convert smp_mb__*()Peter Zijlstra2014-04-181-9/+2
| | | | | | | | | | | | | | | | | | MIPS is interesting and has hardware variants that reorder over ll/sc as well as those that do not. Implement the 2 new barrier functions as per the old barriers. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/n/tip-9ph49jbae3hol9v721sbc2g6@git.kernel.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maciej W. Rozycki" <macro@codesourcery.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* MIPS: Fix gigaton of warning building with microMIPS.Ralf Baechle2014-03-311-14/+14
| | | | | | | | | | | | | | | | 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>
* MIPS: Whitespace cleanup.Ralf Baechle2013-02-011-11/+11
| | | | | | | | 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>
* MIPS: Remove irqflags.h dependency from bitops.hJim Quinlan2012-11-091-82/+32
| | | | | | | | | | | | | | | The "else clause" of most functions in bitops.h invoked raw_local_irq_{save,restore}() and in doing so had a dependency on irqflags.h. This fix moves said code to bitops.c, removing the dependency. Signed-off-by: Jim Quinlan <jim2101024@gmail.com> Cc: linux-mips@linux-mips.org Cc: David Daney <ddaney.cavm@gmail.com> Cc: Kevin Cernekee cernekee@gmail.com Cc: Jim Quinlan <jim2101024@gmail.com> Patchwork: https://patchwork.linux-mips.org/patch/4320/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: bitops.h: Change use of 'unsigned short' to 'int'Jim Quinlan2012-11-091-7/+7
| | | | | | | | | | | | | [ralf@linux-mips.org: No functional change but it's consistent with how use types elsewhere in the code.] Signed-off-by: Jim Quinlan <jim2101024@gmail.com> Cc: linux-mips@linux-mips.org Cc: David Daney <ddaney.cavm@gmail.com> Cc: Kevin Cernekee cernekee@gmail.com Cc: Jim Quinlan <jim2101024@gmail.com> Patchwork: https://patchwork.linux-mips.org/patch/4319/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* mips: fix bug.h build regressionYoichi Yuasa2012-07-181-1/+0
| | | | | | | | | | | | | | | | | | | Commit 377780887 ("bug.h: need linux/kernel.h for TAINT_WARN.") broke all MIPS builds: CC arch/mips/kernel/machine_kexec.o include/linux/log2.h: In function '__ilog2_u32': include/linux/log2.h:34:2: error: implicit declaration of function 'fls' [-Werror=implicit-function-declaration] include/linux/log2.h: In function '__ilog2_u64': include/linux/log2.h:42:2: error: implicit declaration of function 'fls64' [-Werror=implicit-function-declaration] ... Signed-off-by: Yoichi Yuasa <yuasa@linux-mips.org> Tested-by: John Crispin <blogic@openwrt.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Daney <ddaney@caviumnetworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* bitops: remove minix bitops from asm/bitops.hAkinobu Mita2011-03-231-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | minix bit operations are only used by minix filesystem and useless by other modules. Because byte order of inode and block bitmaps is different on each architecture like below: m68k: big-endian 16bit indexed bitmaps h8300, microblaze, s390, sparc, m68knommu: big-endian 32 or 64bit indexed bitmaps m32r, mips, sh, xtensa: big-endian 32 or 64bit indexed bitmaps for big-endian mode little-endian bitmaps for little-endian mode Others: little-endian bitmaps In order to move minix bit operations from asm/bitops.h to architecture independent code in minix filesystem, this provides two config options. CONFIG_MINIX_FS_BIG_ENDIAN_16BIT_INDEXED is only selected by m68k. CONFIG_MINIX_FS_NATIVE_ENDIAN is selected by the architectures which use native byte order bitmaps (h8300, microblaze, s390, sparc, m68knommu, m32r, mips, sh, xtensa). The architectures which always use little-endian bitmaps do not select these options. Finally, we can remove minix bit operations from asm/bitops.h for all architectures. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Ungerer <gerg@uclinux.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Andreas Schwab <schwab@linux-m68k.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Michal Simek <monstr@monstr.eu> Cc: "David S. Miller" <davem@davemloft.net> Cc: Hirokazu Takata <takata@linux-m32r.org> Acked-by: Ralf Baechle <ralf@linux-mips.org> Acked-by: Paul Mundt <lethal@linux-sh.org> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* bitops: remove ext2 non-atomic bitops from asm/bitops.hAkinobu Mita2011-03-231-1/+0
| | | | | | | | | | | | As the result of conversions, there are no users of ext2 non-atomic bit operations except for ext2 filesystem itself. Now we can put them into architecture independent code in ext2 filesystem, and remove from asm/bitops.h for all architectures. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* bitops: introduce little-endian bitops for most architecturesAkinobu Mita2011-03-231-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce little-endian bit operations to the big-endian architectures which do not have native little-endian bit operations and the little-endian architectures. (alpha, avr32, blackfin, cris, frv, h8300, ia64, m32r, mips, mn10300, parisc, sh, sparc, tile, x86, xtensa) These architectures can just include generic implementation (asm-generic/bitops/le.h). Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Mikael Starvik <starvik@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Matthew Wilcox <willy@debian.org> Cc: Grant Grundler <grundler@parisc-linux.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Chris Zankel <chris@zankel.net> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com> Acked-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* MIPS: Get rid of branches to .subsections.Ralf Baechle2010-10-291-149/+121
| | | | | | | | | | | | | | | | | | | | | | | | It was a nice optimization - on paper at least. In practice it results in branches that may exceed the maximum legal range for a branch. We can fight that problem with -ffunction-sections but -ffunction-sections again is incompatible with -pg used by the function tracer. By rewriting the loop around all simple LL/SC blocks to C we reduce the amount of inline assembler and at the same time allow GCC to often fill the branch delay slots with something sensible or whatever else clever optimization it may have up in its sleeve. With this optimization gone we also no longer need -ffunction-sections, so drop it. This optimization was originally introduced in 2.6.21, commit 5999eca25c1fd4b9b9aca7833b04d10fe4bc877d (linux-mips.org) rsp. f65e4fa8e0c6022ad58dc88d1b11b12589ed7f9f (kernel.org). Original fix for the issues which caused me to pull this optimization by Paul Gortmaker <paul.gortmaker@windriver.com>. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Create and use asm/arch_hweight.hDavid Daney2010-08-051-1/+4
| | | | | | | | | | | | | | Some MIPS ISA processor varients can do hweight operations efficiently. Split arch_hweight.h into a seperate file, and implement the operations with __builtin_popcount{,ll} if supported. Signed-off-by: David Daney <ddaney@caviumnetworks.com> To: linux-mips@linux-mips.org Cc: David Daney <ddaney@caviumnetworks.com> Patchwork: https://patchwork.linux-mips.org/patch/1430/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: New macro smp_mb__before_llsc.David Daney2010-02-271-4/+4
| | | | | | | | | | | | | | | | | Replace some instances of smp_llsc_mb() with a new macro smp_mb__before_llsc(). It is used before ll/sc sequences that are documented as needing write barrier semantics. The default implementation of smp_mb__before_llsc() is just smp_llsc_mb(), so there are no changes in semantics. Also simplify definition of smp_mb(), smp_rmb(), and smp_wmb() to be just barrier() in the non-SMP case. Signed-off-by: David Daney <ddaney@caviumnetworks.com> To: linux-mips@linux-mips.org Patchwork: http://patchwork.linux-mips.org/patch/851/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Allow kernel use of LL/SC to be separate from the presence of LL/SC.David Daney2009-09-171-17/+17
| | | | | | | | | | | | | | | | | 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>
* MIPS: Enable CLO / CLZ instructions via separate CPU propertyRalf Baechle2009-05-141-2/+2
| | | | | | | 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>
* MIPS: Clean up MIPSxx-optimized bitop functionsRalf Baechle2008-10-301-38/+76
| | | | Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Move headfiles to new location below arch/mips/includeRalf Baechle2008-10-111-0/+672
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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