kernel/arch/mips/include/asm/msa.h, branch linux-5.1.y

MIPS: MSA: Update helpers to use new asm macros

2018-01-22T20:52:27Z

Update MSA control register access helpers to use the new helpers for parsing register names and creating custom assembly macro instructions. This allows the move via $at to be dropped (saving a total of about 20 bytes of kernel code). Note, this does not alter the equivalent code in .S files, which still uses the $at trick. Signed-off-by: James Hogan Cc: Ralf Baechle Cc: Paul Burton Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17776/

Update MIPS email addresses

2017-11-03T16:02:30Z

MIPS will soon not be a part of Imagination Technologies, and as such many @imgtec.com email addresses will no longer be valid. This patch updates the addresses for those who: - Have 10 or more patches in mainline authored using an @imgtec.com email address, or any patches dated within the past year. - Are still with Imagination but leaving as part of the MIPS business unit, as determined from an internal email address list. - Haven't already updated their email address (ie. JamesH) or expressed a desire to be excluded (ie. Maciej). - Acked v2 or earlier of this patch, which leaves Deng-Cheng, Matt & myself. New addresses are of the form firstname.lastname@mips.com, and all verified against an internal email address list. An entry is added to .mailmap for each person such that get_maintainer.pl will report the new addresses rather than @imgtec.com addresses which will soon be dead. Instances of the affected addresses throughout the tree are then mechanically replaced with the new @mips.com address. Signed-off-by: Paul Burton Cc: Deng-Cheng Zhu Cc: Deng-Cheng Zhu Acked-by: Dengcheng Zhu Cc: Matt Redfearn Cc: Matt Redfearn Acked-by: Matt Redfearn Cc: Andrew Morton Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: trivial@kernel.org Signed-off-by: Linus Torvalds

MIPS: Fix MSA asm warnings in control reg accessors

2016-07-24T10:45:00Z

Building an MSA capable kernel with a toolchain that supports MSA produces warnings such as this: CC arch/mips/kernel/cpu-probe.o {standard input}: Assembler messages: {standard input}:4786: Warning: the `msa' extension requires 64-bit FPRs This is due to ".set msa" without ".set fp=64" in the inline assembly of control register accessors, since MSA requires the 64-bit FPU registers (FR=1). Add the missing fp=64 in these functions to silence the warnings. Signed-off-by: James Hogan Cc: Paul Burton Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13554/ Signed-off-by: Ralf Baechle

MIPS: Fix little endian microMIPS MSA encodings

2016-05-28T10:35:10Z

When the toolchain doesn't support MSA we encode MSA instructions explicitly in assembly. Unfortunately we use .word for both MIPS and microMIPS encodings which is wrong, since 32-bit microMIPS instructions are made up from a pair of halfwords. - The most significant halfword always comes first, so for little endian builds the halves will be emitted in the wrong order. - 32-bit alignment isn't guaranteed, so the assembler may insert a 16-bit nop instruction to pad the instruction stream to a 32-bit boundary. Use the new instruction encoding macros to encode microMIPS MSA instructions correctly. Fixes: d96cc3d1ec5d ("MIPS: Add microMIPS MSA support.") Signed-off-by: James Hogan Cc: Paul Burton Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13312/ Signed-off-by: Ralf Baechle

MIPS: MSA: Fix a link error on `_init_msa_upper' with older GCC

2016-05-17T09:02:45Z

Fix a build regression from commit c9017757c532 ("MIPS: init upper 64b of vector registers when MSA is first used"): arch/mips/built-in.o: In function `enable_restore_fp_context': traps.c:(.text+0xbb90): undefined reference to `_init_msa_upper' traps.c:(.text+0xbb90): relocation truncated to fit: R_MIPS_26 against `_init_msa_upper' traps.c:(.text+0xbef0): undefined reference to `_init_msa_upper' traps.c:(.text+0xbef0): relocation truncated to fit: R_MIPS_26 against `_init_msa_upper' to !CONFIG_CPU_HAS_MSA configurations with older GCC versions, which are unable to figure out that calls to `_init_msa_upper' are indeed dead. Of the many ways to tackle this failure choose the approach we have already taken in `thread_msa_context_live'. [ralf@linux-mips.org: Drop patch segment to junk file.] Signed-off-by: Maciej W. Rozycki Cc: stable@vger.kernel.org # v3.16+ Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13271/ Signed-off-by: Ralf Baechle

MIPS: Introduce accessors for MSA vector registers

2015-09-03T10:07:40Z

Introduce accessor functions allowing the kernel to access arbitrary vector registers using an arbitrary data format. The accessors are implemented in assembly, using macros to avoid massive duplication, in order to make use of the existing support for MSA with & without toolchain support. The accessors will be used in a later patch. Signed-off-by: Paul Burton Cc: linux-mips@linux-mips.org Cc: Leonid Yegoshin Cc: linux-kernel@vger.kernel.org Cc: James Hogan Cc: Markos Chandras Cc: Manuel Lauss Patchwork: https://patchwork.linux-mips.org/patch/10572/ Signed-off-by: Ralf Baechle

MIPS: fix read_msa_* & write_msa_* functions on non-MSA toolchains

2014-08-01T22:06:44Z

Commit d96cc3d1ec5d "MIPS: Add microMIPS MSA support." attempted to use the value of a macro within an inline asm statement but instead emitted a comment leading to the cfcmsa & ctcmsa instructions being omitted. Fix that by passing CFC_MSA_INSN & CTC_MSA_INSN as arguments to the asm statements. Signed-off-by: Paul Burton Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7305/ Signed-off-by: Ralf Baechle

MIPS: init upper 64b of vector registers when MSA is first used

2014-08-01T22:06:44Z

When a task first makes use of MSA we need to ensure that the upper 64b of the vector registers are set to some value such that no information can be leaked to it from the previous task to use MSA context on the CPU. The architecture formerly specified that these bits would be cleared to 0 when a scalar FP instructions wrote to the aliased FP registers, which would have implicitly handled this as the kernel restored scalar FP context. However more recent versions of the specification now state that the value of the bits in such cases is unpredictable. Initialise them explictly to be sure, and set all the bits to 1 rather than 0 for consistency with the least significant 64b. Signed-off-by: Paul Burton Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7497/ Signed-off-by: Ralf Baechle

MIPS: allow msa.h to be included in assembly files

2014-08-01T22:06:43Z

Just #ifdef away the C functions when included from an assembly file, as will be done in a following commit. Signed-off-by: Paul Burton Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7299/ Signed-off-by: Ralf Baechle

Merge branch '3.15-fixes' into mips-for-linux-next

2014-06-04T20:53:02Z