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* MIPS: Fix typosBjorn Helgaas2024-01-081-2/+2
| | | | | | | | | | Fix typos, most reported by "codespell arch/mips". Only touches comments, no code changes. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: linux-mips@vger.kernel.org Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* MIPS: Always use -Wa,-msoft-float and eliminate GAS_HAS_SET_HARDFLOATNathan Chancellor2023-01-261-16/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | -Wa,-msoft-float is tested with as-option, which will be a problem for clang with an upcoming change to move as-option to use KBUILD_AFLAGS instead of KBUILD_CFLAGS due to a lack of '-mno-abicalls' in KBUILD_AFLAGS at the point that this check occurs; $(cflags-y) is added to KBUILD_AFLAGS towards the end of this file. clang: error: ignoring '-fno-PIE' option as it cannot be used with implicit usage of -mabicalls and the N64 ABI [-Werror,-Woption-ignored] This could be resolved by switching to a cc-option check but '$(cflags-y)' would need to be added so that '-mno-abicalls' is present for the test. However, this check is no longer necessary, as -msoft-float is supported by all supported assembler versions (GNU as 2.25+ and LLVM 11+). Eliminate GAS_HAS_SET_HARDFLOAT and all of its uses, inlining SET_HARDFLOAT where necessary. Link: https://lore.kernel.org/202209101939.bvk64Fok-lkp@intel.com/ Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Nathan Chancellor <nathan@kernel.org> Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Anders Roxell <anders.roxell@linaro.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
* MIPS: Remove VR41xx supportThomas Bogendoerfer2022-07-141-14/+0
| | | | | | No (active) developer owns this hardware, so let's remove Linux support. Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* MIPS: remove asm/war.hThomas Bogendoerfer2022-02-221-1/+0
| | | | | | | | The major part for workaround handling has already moved to config options. This change replaces the remaining defines by already available config options and gets rid of war.h Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* MIPS: Avoid macro redefinitionsPaul Cercueil2021-09-231-77/+113
| | | | | | | | | | | | | | | | To be able to compile the kernel with LTO, the assembler macros cannot be declared in the global scope, or the compiler will complain about redefined macros. Update the code so that macros are defined then undefined when they are used. Note that virt support was added in 2.24 and xpa in 2.25. So we still need the TOOLCHAIN defines for them. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* MIPS: set mips32r5 for virt extensionsNick Desaulniers2021-06-291-4/+4
| | | | | | | | | | | Clang's integrated assembler only accepts these instructions when the cpu is set to mips32r5. With this change, we can assemble malta_defconfig with Clang via `make LLVM_IAS=1`. Link: https://github.com/ClangBuiltLinux/linux/issues/763 Reported-by: Dmitry Golovin <dima@golovin.in> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* MIPS: Make check condition for SDBBP consistent with EJTAG specTiezhu Yang2021-02-111-0/+4
| | | | | | | | | | | | | | | | According to MIPS EJTAG Specification [1], a Debug Breakpoint exception occurs when an SDBBP instruction is executed, the CP0_DEBUG bit DBp indicates that a Debug Breakpoint exception occurred. When I read the original code, it looks a little confusing at first glance, just check bit DBp for SDBBP to make the code more readable, it will be much easier to understand. [1] http://www.t-es-t.hu/download/mips/md00047f.pdf Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* MIPS: Loongson-3: Enable COP2 usage in kernelHuacai Chen2020-09-211-0/+7
| | | | | | | | | | | | | | | | | | | Loongson-3's COP2 is Multi-Media coprocessor, it is disabled in kernel mode by default. However, gslq/gssq (16-bytes load/store instructions) overrides the instruction format of lwc2/swc2. If we wan't to use gslq/ gssq for optimization in kernel, we should enable COP2 usage in kernel. Please pay attention that in this patch we only enable COP2 in kernel, which means it will lose ST0_CU2 when a process go to user space (try to use COP2 in user space will trigger an exception and then grab COP2, which is similar to FPU). And as a result, we need to modify the context switching code because the new scheduled process doesn't contain ST0_CU2 in its THERAD_STATUS probably. For zboot, we disable gslq/gssq be generated by toolchain. Signed-off-by: Huacai Chen <chenhc@lemote.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* MIPS: Convert MIPS34K_MISSED_ITLB_WAR into a config optionThomas Bogendoerfer2020-09-071-2/+2
| | | | | | | Use a new config option to enable MIPS 34K ITLB workaround and remove define from different war.h files. Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* MIPS: Remove PNX833x alias NXP_STB22xThomas Bogendoerfer2020-08-241-12/+0
| | | | | | Remove another unused MIPS platform. Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* MIPS: handle Loongson-specific GSExc exceptionWANG Xuerui2020-07-311-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Newer Loongson cores (Loongson-3A R2 and newer) use the implementation-dependent ExcCode 16 to signal Loongson-specific exceptions. The extended cause is put in the non-standard CP0.Diag1 register which is CP0 Register 22 Select 1, called GSCause in Loongson manuals. Inside is an exception code bitfield called GSExcCode, only codes 0 to 6 inclusive are documented (so far, in the Loongson 3A3000 User Manual, Volume 2). During experiments, it was found that some undocumented unprivileged instructions can trigger the also-undocumented GSExcCode 8 on Loongson 3A4000. Processor state is not corrupted, but we cannot continue without further knowledge, and Loongson is not providing that information as of this writing. So we send SIGILL on seeing this exception code to thwart easy local DoS attacks. Other exception codes are made fatal, partly because of insufficient knowledge, also partly because they are not as easily reproduced. None of them are encountered in the wild with upstream kernels and userspace so far. Some older cores (Loongson-3A1000 and Loongson-3B1500) have ExcCode 16 too, but the semantic is equivalent to GSExcCode 0. Because the respective manuals did not mention the CP0.Diag1 register or its read behavior, these cores are not covered in this patch, as MFC0 from non-existent CP0 registers is UNDEFINED according to the MIPS architecture spec. Reviewed-by: Huacai Chen <chenhc@lemote.com> Signed-off-by: WANG Xuerui <git@xen0n.name> Cc: Huacai Chen <chenhc@lemote.com> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com> Cc: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* MIPS: add definitions for Loongson-specific CP0.Diag1 registerWANG Xuerui2020-07-311-0/+8
| | | | | | | | | | | | | This 32-bit CP0 register is named GSCause in Loongson manuals. It carries Loongson extended exception information. We name it Diag1 because we fear the "GSCause" name might get changed in the future. Reviewed-by: Huacai Chen <chenhc@lemote.com> Signed-off-by: WANG Xuerui <git@xen0n.name> Cc: Huacai Chen <chenhc@lemote.com> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com> Cc: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* MIPS: Unify naming style of vendor CP0.Config6 bitsHuacai Chen2020-07-081-14/+14
| | | | | | | | | | Other vendor-defined registers use the vendor name as a prefix, not an infix, so unify the naming style of CP0.Config6 bits. Suggested-by: Maciej W. Rozycki" <macro@linux-mips.org> Signed-off-by: Huacai Chen <chenhc@lemote.com> Reviewed-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* KVM: MIPS: Add CONFIG6 and DIAG registers emulationHuacai Chen2020-06-041-0/+4
| | | | | | | | | | | | | Loongson-3 has CONFIG6 and DIAG registers which need to be emulated. CONFIG6 is mostly used to enable/disable FTLB and SFB, while DIAG is mostly used to flush BTB, ITLB, DTLB, VTLB and FTLB. Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Reviewed-by: Aleksandar Markovic <aleksandar.qemu.devel@gmail.com> Signed-off-by: Huacai Chen <chenhc@lemote.com> Co-developed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Message-Id: <1590220602-3547-13-git-send-email-chenhc@lemote.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: Tidy up CP0.Config6 bits definitionHuacai Chen2020-05-241-13/+24
| | | | | | | | | | | | | | | | | | CP0.Config6 is a Vendor-defined register whose bits definitions are different from one to another. Recently, Xuerui's Loongson-3 patch and Serge's P5600 patch make the definitions inconsistency and unclear. To make life easy, this patch tidy the definition up: 1, Add a _MTI_ infix for proAptiv/P5600 feature bits; 2, Add a _LOONGSON_ infix for Loongson-3 feature bits; 3, Add bit6/bit7 definition for Loongson-3 which will be used later. All existing users of these macros are updated. Cc: WANG Xuerui <git@xen0n.name> Cc: Serge Semin <Sergey.Semin@baikalelectronics.ru> Signed-off-by: Huacai Chen <chenhc@lemote.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* mips: Add CONFIG/CONFIG6/Cause reg fields macroSerge Semin2020-05-221-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | There are bit fields which persist in the MIPS CONFIG and CONFIG6 registers, but haven't been described in the generic mipsregs.h header so far. In particular, the generic CONFIG bitfields are BE - endian mode, BM - burst mode, SB - SimpleBE, OCP interface mode indicator, UDI - user-defined "CorExtend" instructions, DSP - data scratch pad RAM present, ISP - instruction scratch pad RAM present, etc. The core-specific CONFIG6 bitfields are JRCD - jump register cache prediction disable, R6 - MIPSr6 extensions enable, IFUPerfCtl - IFU performance control, SPCD - sleep state performance counter, DLSB - disable load/store bonding. A new exception code reported in the ExcCode field of the Cause register: 30 - Parity/ECC error exception happened on either fetch, load or cache refill. Lets add them to the mipsregs.h header to be used in future platform code, which have them utilized. Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Paul Burton <paulburton@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Rob Herring <robh+dt@kernel.org> Cc: devicetree@vger.kernel.org Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* mips: Add CP0 Write Merge config supportSerge Semin2020-05-221-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CP0 config register may indicate whether write-through merging is allowed. Currently there are two types of the merging available: SysAD Valid and Full modes. Whether each of them are supported by the core is implementation dependent. Moreover whether the ability to change the mode also depends on the chip family instance. Taking into account all of this we created a dedicated mm_config() method to detect and enable merging if it's supported. It is called for MIPS-type processors at CPU-probe stage and attempts to detect whether the write merging is available. If it's known to be supported and switchable, then switch on the full mode. Otherwise just perform the CP0.Config.MM field analysis. In addition there are platforms like InterAptiv/ProAptiv, which do have the MM bit field set by default, but having write-through cacheing unsupported makes write-merging also unsupported. In this case we just ignore the MM field value. Co-developed-by: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru> Signed-off-by: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru> Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Paul Burton <paulburton@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Rob Herring <robh+dt@kernel.org> Cc: devicetree@vger.kernel.org Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* mips: MAAR: Use more precise address maskSerge Semin2020-05-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | Indeed according to the MIPS32 Privileged Resource Architecgture the MAAR pair register address field either takes [12:31] bits for non-XPA systems and [12:55] otherwise. In any case the current address mask is just wrong for 64-bit and 32-bits XPA chips. So lets extend it to 59-bits of physical address value. This shall cover the 64-bits architecture and systems with XPA enabled, and won't cause any problem for non-XPA 32-bit systems, since address values exceeding the architecture specific MAAR mask will be just truncated with setting zeros in the unsupported upper bits. Co-developed-by: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru> Signed-off-by: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru> Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Paul Burton <paulburton@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Rob Herring <robh+dt@kernel.org> Cc: devicetree@vger.kernel.org Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* mips: MAAR: Add XPA mode supportSerge Semin2020-05-191-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | When XPA mode is enabled the normally 32-bits MAAR pair registers are extended to be of 64-bits width as in pure 64-bits MIPS architecture. In this case the MAAR registers can enable the speculative loads/stores for addresses of up to 39-bits width. But in this case the process of the MAAR initialization changes a bit. The upper 32-bits of the registers are supposed to be accessed by mean of the dedicated instructions mfhc0/mthc0 and there is a CP0.MAAR.VH bit which should be set together with CP0.MAAR.VL as indication of the boundary validity. All of these peculiarities were taken into account in this commit so the speculative loads/stores would work when XPA mode is enabled. Co-developed-by: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru> Signed-off-by: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru> Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Paul Burton <paulburton@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Rob Herring <robh+dt@kernel.org> Cc: linux-pm@vger.kernel.org Cc: devicetree@vger.kernel.org Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* MIPS: define more Loongson CP0.Config6 and CP0.Diag feature bitsWANG Xuerui2020-05-171-0/+6
| | | | | | | | | | | These are exposed to userland alternatively via the new CPUCFG instruction on Loongson-3A R4 and above. Add definitions for readback on older cores. Signed-off-by: WANG Xuerui <git@xen0n.name> Cc: Huacai Chen <chenhc@lemote.com> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
* MIPS: Add MAC2008 SupportJiaxun Yang2020-01-231-0/+3
| | | | | | | | | | | | | | | | | | | | MAC2008 means the processor implemented IEEE754 style Fused MADD instruction. It was introduced in Release3 but removed in Release5. The toolchain support of MAC2008 have never landed except for Loongson processors. This patch aimed to disabled the MAC2008 if it's optional. For MAC2008 only processors, we corrected math-emu behavior to align with actual hardware behavior. Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> [paulburton@kernel.org: Fixup MIPSr2-r5 check in cpu_set_fpu_2008.] Signed-off-by: Paul Burton <paulburton@kernel.org> Cc: linux-mips@vger.kernel.org Cc: chenhc@lemote.com Cc: paul.burton@mips.com Cc: linux-kernel@vger.kernel.org
* MIPS: Ingenic: Disable abandoned HPTLB function.Zhou Yanjie2019-11-221-0/+6
| | | | | | | | | | | | | | | | | | | | | | | JZ4760/JZ4770/JZ4775/X1000/X1500 has an abandoned huge page tlb, this mode is not compatible with the MIPS standard, it will cause tlbmiss and into an infinite loop (line 21 in the tlb-funcs.S) when starting the init process. write 0xa9000000 to cp0 register 5 sel 4 to disable this function to prevent getting stuck. Confirmed by Ingenic, this operation will not adversely affect processors without HPTLB function. Signed-off-by: Zhou Yanjie <zhouyanjie@zoho.com> Acked-by: Paul Cercueil <paul@crapouillou.net> Signed-off-by: Paul Burton <paulburton@kernel.org> Cc: linux-mips@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: ralf@linux-mips.org Cc: jhogan@kernel.org Cc: jiaxun.yang@flygoat.com Cc: gregkh@linuxfoundation.org Cc: malat@debian.org Cc: tglx@linutronix.de Cc: chenhc@lemote.com
* MIPS: Ingenic: Disable broken BTB lookup optimization.Zhou Yanjie2019-08-061-0/+4
| | | | | | | | | | | | | | | | | | | | | | | In order to further reduce power consumption, the XBurst core by default attempts to avoid branch target buffer lookups by detecting & special casing loops. This feature will cause BogoMIPS and lpj calculate in error. Set cp0 config7 bit 4 to disable this feature. Signed-off-by: Zhou Yanjie <zhouyanjie@zoho.com> Signed-off-by: Paul Burton <paul.burton@mips.com> Cc: linux-mips@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: ralf@linux-mips.org Cc: paul@crapouillou.net Cc: jhogan@kernel.org Cc: malat@debian.org Cc: gregkh@linuxfoundation.org Cc: tglx@linutronix.de Cc: allison@lohutok.net Cc: syq@debian.org Cc: chenhc@lemote.com Cc: jiaxun.yang@flygoat.com
* MIPS: MemoryMapID (MMID) SupportPaul Burton2019-02-041-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce support for using MemoryMapIDs (MMIDs) as an alternative to Address Space IDs (ASIDs). The major difference between the two is that MMIDs are global - ie. an MMID uniquely identifies an address space across all coherent CPUs. In contrast ASIDs are non-global per-CPU IDs, wherein each address space is allocated a separate ASID for each CPU upon which it is used. This global namespace allows a new GINVT instruction be used to globally invalidate TLB entries associated with a particular MMID across all coherent CPUs in the system, removing the need for IPIs to invalidate entries with separate ASIDs on each CPU. The allocation scheme used here is largely borrowed from arm64 (see arch/arm64/mm/context.c). In essence we maintain a bitmap to track available MMIDs, and MMIDs in active use at the time of a rollover to a new MMID version are preserved in the new version. The allocation scheme requires efficient 64 bit atomics in order to perform reasonably, so this support depends upon CONFIG_GENERIC_ATOMIC64=n (ie. currently it will only be included in MIPS64 kernels). The first, and currently only, available CPU with support for MMIDs is the MIPS I6500. This CPU supports 16 bit MMIDs, and so for now we cap our MMIDs to 16 bits wide in order to prevent the bitmap growing to absurd sizes if any future CPU does implement 32 bit MMIDs as the architecture manuals suggest is recommended. When MMIDs are in use we also make use of GINVT instruction which is available due to the global nature of MMIDs. By executing a sequence of GINVT & SYNC 0x14 instructions we can avoid the overhead of an IPI to each remote CPU in many cases. One complication is that GINVT will invalidate wired entries (in all cases apart from type 0, which targets the entire TLB). In order to avoid GINVT invalidating any wired TLB entries we set up, we make sure to create those entries using a reserved MMID (0) that we never associate with any address space. Also of note is that KVM will require further work in order to support MMIDs & GINVT, since KVM is involved in allocating IDs for guests & in configuring the MMU. That work is not part of this patch, so for now when MMIDs are in use KVM is disabled. Signed-off-by: Paul Burton <paul.burton@mips.com> Cc: linux-mips@vger.kernel.org
* MIPS: Add GINVT instruction helpersPaul Burton2019-02-041-0/+7
| | | | | | | | | | | | | | Add a family of ginvt_* functions making it easy to emit a GINVT instruction to globally invalidate TLB entries. We make use of the _ASM_MACRO infrastructure to support emitting the instructions even if the assembler isn't new enough to support them natively. An associated STYPE_GINV definition & sync_ginv() function are added to emit a sync instruction of type 0x14, which operates as a completion barrier for these new GINVT (and GINVI) instructions. Signed-off-by: Paul Burton <paul.burton@mips.com> Cc: linux-mips@vger.kernel.org
* MIPS: Avoid using .set mips0 to restore ISAPaul Burton2018-11-091-10/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We currently have 2 commonly used methods for switching ISA within assembly code, then restoring the original ISA. 1) Using a pair of .set push & .set pop directives. For example: .set push .set mips32r2 <some_insn> .set pop 2) Using .set mips0 to restore the ISA originally specified on the command line. For example: .set mips32r2 <some_insn> .set mips0 Unfortunately method 2 does not work with nanoMIPS toolchains, where the assembler rejects the .set mips0 directive like so: Error: cannot change ISA from nanoMIPS to mips0 In preparation for supporting nanoMIPS builds, switch all instances of method 2 in generic non-platform-specific code to use push & pop as in method 1 instead. The .set push & .set pop is arguably cleaner anyway, and if nothing else it's good to consistently use one method. Signed-off-by: Paul Burton <paul.burton@mips.com> Patchwork: https://patchwork.linux-mips.org/patch/21037/ Cc: linux-mips@linux-mips.org
* MIPS: Cleanup DSP ASE detectionPaul Burton2018-10-171-1/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | Currently we hardcode a list of files for which we specify that the toolchain has DSP ASE support when building for MIPSr2 only. This has a number of problems: 1) It doesn't actually ensure that the toolchain supports the DSP ASE at all. 2) It's fragile if we try to use DSP ASE macros in other files. 3) It makes no provision for MIPSr6 & later systems which also support the DSP ASE & end up using the .word directive implementation of the DSP macros. Fix this by detecting assembler support for the DSP ASE globally, not just for a small set of files, and not just for MIPSr2. This now exposes use of toolchain DSP support to kernel builds targeting MIPSr1 and older, so we add .set MIPS_ISA_LEVEL directives prior to all .set dsp directives in order to prevent the assembler from complaining that the DSP ASE is only supported with MIPSr2 & higher. Signed-off-by: Paul Burton <paul.burton@mips.com> Patchwork: https://patchwork.linux-mips.org/patch/20901/ Cc: linux-mips@linux-mips.org
* Merge tag 'mips_4.19' of ↵Linus Torvalds2018-08-141-10/+19
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux Pull MIPS updates from Paul Burton: "Here are the main MIPS changes for 4.19. An overview of the general architecture changes: - Massive DMA ops refactoring from Christoph Hellwig (huzzah for deleting crufty code!). - We introduce NT_MIPS_DSP & NT_MIPS_FP_MODE ELF notes & corresponding regsets to expose DSP ASE & floating point mode state respectively, both for live debugging & core dumps. - We better optimize our code by hard-coding cpu_has_* macros at compile time where their values are known due to the ISA revision that the kernel build is targeting. - The EJTAG exception handler now better handles SMP systems, where it was previously possible for CPUs to clobber a register value saved by another CPU. - Our implementation of memset() gained a couple of fixes for MIPSr6 systems to return correct values in some cases where stores fault. - We now implement ioremap_wc() using the uncached-accelerated cache coherency attribute where supported, which is detected during boot, and fall back to plain uncached access where necessary. The MIPS-specific (and unused in tree) ioremap_uncached_accelerated() & ioremap_cacheable_cow() are removed. - The prctl(PR_SET_FP_MODE, ...) syscall is better supported for SMP systems by reworking the way we ensure remote CPUs that may be running threads within the affected process switch mode. - Systems using the MIPS Coherence Manager will now set the MIPS_IC_SNOOPS_REMOTE flag to avoid some unnecessary cache maintenance overhead when flushing the icache. - A few fixes were made for building with clang/LLVM, which now sucessfully builds kernels for many of our platforms. - Miscellaneous cleanups all over. And some platform-specific changes: - ar7 gained stubs for a few clock API functions to fix build failures for some drivers. - ath79 gained support for a few new SoCs, a few fixes & better gpio-keys support. - Ci20 now exposes its SPI bus using the spi-gpio driver. - The generic platform can now auto-detect a suitable value for PHYS_OFFSET based upon the memory map described by the device tree, allowing us to avoid wasting memory on page book-keeping for systems where RAM starts at a non-zero physical address. - Ingenic systems using the jz4740 platform code now link their vmlinuz higher to allow for kernels of a realistic size. - Loongson32 now builds the kernel targeting MIPSr1 rather than MIPSr2 to avoid CPU errata. - Loongson64 gains a couple of fixes, a workaround for a write buffering issue & support for the Loongson 3A R3.1 CPU. - Malta now uses the piix4-poweroff driver to handle powering down. - Microsemi Ocelot gained support for its SPI bus & NOR flash, its second MDIO bus and can now be supported by a FIT/.itb image. - Octeon saw a bunch of header cleanups which remove a lot of duplicate or unused code" * tag 'mips_4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (123 commits) MIPS: Remove remnants of UASM_ISA MIPS: netlogic: xlr: Remove erroneous check in nlm_fmn_send() MIPS: VDSO: Force link endianness MIPS: Always specify -EB or -EL when using clang MIPS: Use dins to simplify __write_64bit_c0_split() MIPS: Use read-write output operand in __write_64bit_c0_split() MIPS: Avoid using array as parameter to write_c0_kpgd() MIPS: vdso: Allow clang's --target flag in VDSO cflags MIPS: genvdso: Remove GOT checks MIPS: Remove obsolete MIPS checks for DST node "chosen@0" MIPS: generic: Remove input symbols from defconfig MIPS: Delete unused code in linux32.c MIPS: Remove unused sys_32_mmap2 MIPS: Remove nabi_no_regargs mips: dts: mscc: enable spi and NOR flash support on ocelot PCB123 mips: dts: mscc: Add spi on Ocelot MIPS: Loongson: Merge load addresses MIPS: Loongson: Set Loongson32 to MIPS32R1 MIPS: mscc: ocelot: add interrupt controller properties to GPIO controller MIPS: generic: Select MIPS_AUTO_PFN_OFFSET ...
| * MIPS: Use dins to simplify __write_64bit_c0_split()Paul Burton2018-08-071-1/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The code in __write_64bit_c0_split() is used by MIPS32 kernels running on MIPS64 CPUs to write a 64-bit value to a 64-bit coprocessor 0 register using a single 64-bit dmtc0 instruction. It does this by combining the 2x 32-bit registers used to hold the 64-bit value into a single register, which in the existing code involves three steps: 1) Zero extend register A which holds bits 31:0 of our data, since it may have previously held a sign-extended value. 2) Shift register B which holds bits 63:32 of our data in bits 31:0 left by 32 bits, such that the bits forming our data are in the position they'll be in the final 64-bit value & bits 31:0 of the register are zero. 3) Or the two registers together to form the 64-bit value in one 64-bit register. From MIPS r2 onwards we have a dins instruction which can effectively perform all 3 of those steps using a single instruction. Add a path for MIPS r2 & beyond which uses dins to take bits 31:0 from register B & insert them into bits 63:32 of register A, giving us our full 64-bit value in register A with one instruction. Since we know that MIPS r2 & above support the sel field for the dmtc0 instruction, we don't bother special casing sel==0. Omiting the sel field would assemble to exactly the same instruction as when we explicitly specify that it equals zero. Signed-off-by: Paul Burton <paul.burton@mips.com>
| * MIPS: Use read-write output operand in __write_64bit_c0_split()Paul Burton2018-08-071-9/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit c22c80431055 ("MIPS: Fix input modify in __write_64bit_c0_split()") modified __write_64bit_c0_split() constraints such that we have both an input & an output which we hope to assign to the same registers, and modify the output rather than incorrectly clobbering an input. The way in which we use both an output & an input parameter with the input constrained to share the output registers is a little convoluted & also problematic for clang, which complains if the input & output values have different widths. For example: In file included from kernel/fork.c:98: ./arch/mips/include/asm/mmu_context.h:149:19: error: unsupported inline asm: input with type 'unsigned long' matching output with type 'unsigned long long' write_c0_entryhi(cpu_asid(cpu, next)); ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~ ./arch/mips/include/asm/mmu_context.h:93:2: note: expanded from macro 'cpu_asid' (cpu_context((cpu), (mm)) & cpu_asid_mask(&cpu_data[cpu])) ^ ./arch/mips/include/asm/mipsregs.h:1617:65: note: expanded from macro 'write_c0_entryhi' #define write_c0_entryhi(val) __write_ulong_c0_register($10, 0, val) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~ ./arch/mips/include/asm/mipsregs.h:1430:39: note: expanded from macro '__write_ulong_c0_register' __write_64bit_c0_register(reg, sel, val); \ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~ ./arch/mips/include/asm/mipsregs.h:1400:41: note: expanded from macro '__write_64bit_c0_register' __write_64bit_c0_split(register, sel, value); \ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~ ./arch/mips/include/asm/mipsregs.h:1498:13: note: expanded from macro '__write_64bit_c0_split' : "r,0" (val)); \ ^~~ We can both fix this build failure & simplify the code somewhat by assigning the __tmp variable with the input value in C prior to our inline assembly, and then using a single read-write output operand (ie. a constraint beginning with +) to provide this value to our assembly. Signed-off-by: Paul Burton <paul.burton@mips.com>
| * MIPS: Loongson64: Define and use some CP0 registersHuacai Chen2018-07-241-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Defines CP0_CONFIG3, CP0_CONFIG6, CP0_PAGEGRAIN and use them in kernel-entry-init.h for Loongson64. Signed-off-by: Huacai Chen <chenhc@lemote.com> Signed-off-by: Paul Burton <paul.burton@mips.com> Patchwork: https://patchwork.linux-mips.org/patch/19264/ Cc: Ralf Baechle <ralf@linux-mips.org> Cc: James Hogan <james.hogan@mips.com> Cc: linux-mips@linux-mips.org Cc: Fuxin Zhang <zhangfx@lemote.com> Cc: Zhangjin Wu <wuzhangjin@gmail.com> Cc: Huacai Chen <chenhuacai@gmail.com>
* | Revert "MIPS: BCM47XX: Enable 74K Core ExternalSync for PCIe erratum"Rafał Miłecki2018-07-271-3/+0
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit 2a027b47dba6 ("MIPS: BCM47XX: Enable 74K Core ExternalSync for PCIe erratum"). Enabling ExternalSync caused a regression for BCM4718A1 (used e.g. in Netgear E3000 and ASUS RT-N16): it simply hangs during PCIe initialization. It's likely that BCM4717A1 is also affected. I didn't notice that earlier as the only BCM47XX devices with PCIe I own are: 1) BCM4706 with 2 x 14e4:4331 2) BCM4706 with 14e4:4360 and 14e4:4331 it appears that BCM4706 is unaffected. While BCM5300X-ES300-RDS.pdf seems to document that erratum and its workarounds (according to quotes provided by Tokunori) it seems not even Broadcom follows them. According to the provided info Broadcom should define CONF7_ES in their SDK's mipsinc.h and implement workaround in the si_mips_init(). Checking both didn't reveal such code. It *could* mean Broadcom also had some problems with the given workaround. Signed-off-by: Rafał Miłecki <rafal@milecki.pl> Signed-off-by: Paul Burton <paul.burton@mips.com> Reported-by: Michael Marley <michael@michaelmarley.com> Patchwork: https://patchwork.linux-mips.org/patch/20032/ URL: https://bugs.openwrt.org/index.php?do=details&task_id=1688 Cc: Tokunori Ikegami <ikegami@allied-telesis.co.jp> Cc: Hauke Mehrtens <hauke@hauke-m.de> Cc: Chris Packham <chris.packham@alliedtelesis.co.nz> Cc: James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org
* MIPS: BCM47XX: Enable 74K Core ExternalSync for PCIe erratumTokunori Ikegami2018-06-181-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The erratum and workaround are described by BCM5300X-ES300-RDS.pdf as below. R10: PCIe Transactions Periodically Fail Description: The BCM5300X PCIe does not maintain transaction ordering. This may cause PCIe transaction failure. Fix Comment: Add a dummy PCIe configuration read after a PCIe configuration write to ensure PCIe configuration access ordering. Set ES bit of CP0 configu7 register to enable sync function so that the sync instruction is functional. Resolution: hndpci.c: extpci_write_config() hndmips.c: si_mips_init() mipsinc.h CONF7_ES This is fixed by the CFE MIPS bcmsi chipset driver also for BCM47XX. Also the dummy PCIe configuration read is already implemented in the Linux BCMA driver. Enable ExternalSync in Config7 when CONFIG_BCMA_DRIVER_PCI_HOSTMODE=y too so that the sync instruction is externalised. Signed-off-by: Tokunori Ikegami <ikegami@allied-telesis.co.jp> Reviewed-by: Paul Burton <paul.burton@mips.com> Acked-by: Hauke Mehrtens <hauke@hauke-m.de> Cc: Chris Packham <chris.packham@alliedtelesis.co.nz> Cc: Rafał Miłecki <zajec5@gmail.com> Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/19461/ Signed-off-by: James Hogan <jhogan@kernel.org>
* MIPS: Probe for MIPS MT perf counters per TCMatt Redfearn2018-05-151-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Processors implementing the MIPS MT ASE may have performance counters implemented per core or per TC. Processors implemented by MIPS Technologies signify presence per TC through a bit in the implementation specific Config7 register. Currently the code which probes for their presence blindly reads a magic number corresponding to this bit, despite it potentially having a different meaning in the CPU implementation. Since CPU features are generally detected by cpu-probe.c, perform the detection here instead. Introduce cpu_set_mt_per_tc_perf which checks the bit in config7 and call it from MIPS CPUs known to implement this bit and the MT ASE, specifically, the 34K, 1004K and interAptiv. Once the presence of the per-tc counter is indicated in cpu_data, tests for it can be updated to use this flag. Suggested-by: James Hogan <jhogan@kernel.org> Signed-off-by: Matt Redfearn <matt.redfearn@mips.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Matt Redfearn <matt.redfearn@mips.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Maciej W. Rozycki <macro@mips.com> Cc: linux-mips@linux-mips.org> Patchwork: https://patchwork.linux-mips.org/patch/19136/ Signed-off-by: James Hogan <jhogan@kernel.org>
* MIPS: Add crc instruction support flag to elf_hwcapMarcin Nowakowski2018-02-191-0/+1
| | | | | | | | | | | | | | Indicate that CRC32 and CRC32C instuctions are supported by the CPU through elf_hwcap flags. This will be used by a follow-up commit that introduces crc32(c) crypto acceleration modules and is required by GENERIC_CPU_AUTOPROBE feature. Signed-off-by: Marcin Nowakowski <marcin.nowakowski@mips.com> Signed-off-by: James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/18600/
* MIPS: XPA: Standardise readx/writex accessorsJames Hogan2018-01-221-10/+10
| | | | | | | | | | | | | | | | | Now that we are using assembler macros to implement XPA instructions on toolchains which don't support them, pass Cop0 register names to the __{readx,writex}_32bit_c0_register macros in $n format rather than register numbers. Also pass a register select which may be useful in future (for example for MemoryMapID field of WatchHi registers on I6500). This is to make them consistent with the normal Cop0 register access macros which they were originally based on. Signed-off-by: James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17777/
* MIPS: XPA: Allow use of $0 (zero) to MTHC0James Hogan2018-01-221-2/+2
| | | | | | | | | | Tweak __writex_32bit_c0_register() to allow the compiler to use $0 (the zero register) as an input to the mthc0 instruction. Signed-off-by: James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17774/
* MIPS: XPA: Use XPA instructions in assemblyJames Hogan2018-01-221-10/+16
| | | | | | | | | | | | | | | | | Utilise XPA instructions MFHC0 & MTHC0 in inline assembly instead of directly encoding them with the _ASM_INSN* macros, and transparently implement these instructions as assembler macros if the toolchain doesn't support them natively, using the recently introduced assembler macro helpers. The old direct encodings were restricted to using the register $at, so this allows the extra register moves to go away (saving a grand total of 24 bytes). Signed-off-by: James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17775/
* MIPS: VZ: Pass GC0 register names in $n formatJames Hogan2018-01-221-188/+188
| | | | | | | | | | | | | | Now that we are using assembler macros to implement VZ instructions on toolchains which don't support them, pass VZ guest Cop0 register names to the __{read,write}_{32bit,ulong,64bit}_gc0_register macros in $n format rather than register numbers. This is to make them consistent with the normal root Cop0 register access macros which they were originally based on. Signed-off-by: James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17773/
* MIPS: VZ: Update helpers to use new asm macrosJames Hogan2018-01-221-127/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Update VZ guest register & guest TLB access helpers to use the new assembly macros for parsing register names and creating custom assembly macro instructions, which has a number of advantages: - Better code can be generated on toolchains which don't support VZ, more closely matching those which do, since there is no need to bounce values via the $at register. Some differences still remain due to the inability to safely fill branch delay slots and R6 compact branch forbidden slots with explicitly encoded instructions, resulting in some extra NOPs added by the assembler. - Some code duplication between toolchains which do and don't support VZ instructions is removed, since the helpers are only implemented once. When the toolchain doesn't implement the instruction an assembly macro implements it instead. - Instruction encodings are kept together in the source. On a generic kernel with KVM VZ support enabled this change saves about 2.5KiB of kernel code when TOOLCHAIN_SUPPORTS_VIRT=n, bringing it down to about 0.5KiB more than when TOOLCHAIN_SUPPORTS_VIRT=y on r6, and just 68 bytes more on r2. Signed-off-by: James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17772/
* MIPS: Add helpers for assembler macro instructionsJames Hogan2018-01-221-0/+83
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implement a parse_r assembler macro in asm/mipsregs.h to parse a register in $n form, and a few C macros for defining assembler macro instructions. These can be used to more transparently support older binutils versions which don't support for example the msa, virt, xpa, or crc instructions. In particular they overcome the difficulty of turning a register name in $n form into an instruction encoding suitable for giving to .word / .hword, which is particularly problematic when needed from inline assembly where the compiler is responsible for register allocation. Traditionally this had required the use of $at and an extra MOV instruction, but for CRC instructions with multiple GP register operands that approach becomes more difficult. Three assembler macro creation helpers are added: - _ASM_MACRO_0(OP, ENC) This is to define an assembler macro for an instruction which has no operands, for example the VZ TLBGR instruction. - _ASM_MACRO_2R(OP, R1, R2, ENC) This is to define an assembler macro for an instruction which has 2 register operands, for example the CFCMSA instruction. - _ASM_MACRO_3R(OP, R1, R2, R3, ENC) This is to define an assembler macro for an instruction which has 3 register operands, for example the crc32 instructions. - _ASM_MACRO_2R_1S(OP, R1, R2, SEL3, ENC) This is to define an assembler macro for a Cop0 move instruction, with 2 register operands and an optional register select operand which defaults to 0, for example the VZ MFGC0 instruction. Suggested-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Marcin Nowakowski <marcin.nowakowski@mips.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17770/
* MIPS: mipsregs.h: Make read_c0_prid use const accessorJames Hogan2018-01-091-1/+1
| | | | | | | | | | | | | | | | | | | | Make read_c0_prid() use the new constant accessor macros so that it can potentially be optimised or removed by the compiler. This is particularly important under virtualisation, where even with hardware assisted virtualisation (VZ), access to the PRid register may need to be emulated by the hypervisor. In particular this helps eliminate the read of the PRid register in the rather frequently called add_interrupt_randomness() (which calls into arch/mips/include/asm/timex.h) when the prid is unused but the read can't be removed due to the inline asm being marked __volatile__. Reported-by: Yann LeDu <Yann.LeDu@imgtec.com> Signed-off-by: James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Maciej W. Rozycki <macro@mips.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17923/
* MIPS: mipsregs.h: Add read const Cop0 macrosJames Hogan2018-01-091-10/+27
| | | | | | | | | | | | | | | | | | | | Some Cop0 registers are constant and have no side effects when read. There is no need for the inline asm to read these to be marked __volatile__, and doing so prevents them from being removed by the compiler. Add a few new accessor macros to handle these registers more efficiently (especially for the sake of running in a guest where redundant access to the register may trap to the hypervisor): __read_const_32bit_c0_register() __read_const_64bit_c0_register() __read_const_ulong_c0_register() Signed-off-by: James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Maciej W. Rozycki <macro@mips.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17922/
* MIPS: Use SLL by 0 for 32-bit truncation in `__read_64bit_c0_split'Maciej W. Rozycki2017-11-081-8/+6
| | | | | | | | | | | | | | | Optimize `__read_64bit_c0_split' and reduce the instruction count by 1, observing that a DSLL/DSRA pair by 32, is equivalent to SLL by 0, which architecturally truncates the value requested to 32 bits on 64-bit MIPS hardware regardless of whether the input operand is or is not a properly sign-extended 32-bit value. Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Reviewed-by: James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17399/ Signed-off-by: James Hogan <jhogan@kernel.org>
* MIPS: Fix input modify in __write_64bit_c0_split()James Hogan2017-09-211-6/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The inline asm in __write_64bit_c0_split() modifies the 64-bit input operand by shifting the high register left by 32, and constructing the full 64-bit value in the low register (even on a 32-bit kernel), so if that value is used again it could cause breakage as GCC would assume the registers haven't changed when they have. To quote the GCC extended asm documentation: > Warning: Do not modify the contents of input-only operands (except for > inputs tied to outputs). The compiler assumes that on exit from the > asm statement these operands contain the same values as they had > before executing the statement. Avoid modifying the input by using a temporary variable as an output which is modified instead of the input and not otherwise used. The asm is always __volatile__ so GCC shouldn't optimise it out. The low register of the temporary output is written before the high register of the input is read, so we have two constraint alternatives, one where both use the same registers (for when the input value isn't subsequently used), and one with an early clobber on the output in case the low output uses the same register as the high input. This allows the resulting assembly to remain mostly unchanged. A diff of a MIPS32r6 kernel reveals only three differences, two in relation to write_c0_r10k_diag() in cpu_probe() (register allocation rearranged slightly but otherwise identical), and one in relation to write_c0_cvmmemctl2() in kvm_vz_local_flush_guesttlb_all(), but the octeon CPU is only supported on 64-bit kernels where __write_64bit_c0_split() isn't used so that shouldn't matter in practice. So there currently doesn't appear to be anything broken by this bug. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17315/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Add accessor & bit definitions for GlobalNumberPaul Burton2017-08-301-0/+13
| | | | | | | | | | | | | | | | | MIPSr6 introduces a GlobalNumber register, which is required when VPs are implemented (ie. when multi-threading is supported) but otherwise optional. The register contains sufficient information to uniquely identify a VP within a system using its cluster number, core number & VP ID. In preparation for using this register & its fields, introduce an accessor macro for it & define its various bits with the typical style preprocessor macros. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17007/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: MIPS16e2: Identify ASE presenceMaciej W. Rozycki2017-07-051-0/+1
| | | | | | | | | | | | | | | | | | | | | | | Identify the presence of the MIPS16e2 ASE as per the architecture specification[1], by checking for CP0 Config5.CA2 bit being 1[2]. References: [1] "MIPS32 Architecture for Programmers: MIPS16e2 Application-Specific Extension Technical Reference Manual", Imagination Technologies Ltd., Document Number: MD01172, Revision 01.00, April 26, 2016, Section 1.2 "Software Detection of the ASE", p. 5 [2] "MIPS32 interAptiv Multiprocessing System Software User's Manual", Imagination Technologies Ltd., Document Number: MD00904, Revision 02.01, June 15, 2016, Section 2.2.1.6 "Device Configuration 5 -- Config5 (CP0 Register 16, Select 5)", pp. 71-72 Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16094/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* KVM: MIPS/VZ: Handle Octeon III guest.PRid registerJames Hogan2017-03-281-0/+2
| | | | | | | | | | | | | | | Octeon III implements a read-only guest CP0_PRid register, so add cases to the KVM register access API for Octeon to ensure the correct value is read and writes are ignored. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Daney <david.daney@cavium.com> Cc: Andreas Herrmann <andreas.herrmann@caviumnetworks.com> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
* MIPS: Add Octeon III register accessors & definitionsJames Hogan2017-03-281-0/+36
| | | | | | | | | | | | | | | | Add accessors for some VZ related Cavium Octeon III specific COP0 registers, along with field definitions. These will mostly be used by KVM to set up interrupt routing and partition the TLB between root and guest. Signed-off-by: James Hogan <james.hogan@imgtec.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Cc: David Daney <david.daney@cavium.com> Cc: Andreas Herrmann <andreas.herrmann@caviumnetworks.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
* MIPS: Add some missing guest CP0 accessors & defsJames Hogan2017-03-281-2/+14
| | | | | | | | | | | | | | | | | | | | | | | | Add some missing guest accessors and register field definitions for KVM for MIPS VZ to make use of. Guest CP0_LLAddr register accessors and definitions for the LLB field allow KVM to clear the guest LLB to cancel in-progress LL/SC atomics on restore, and to emulate accesses by the guest to the CP0_LLAddr register. Bitwise modifiers and definitions for the guest CP0_Wired and CP0_Config1 registers allow KVM to modify fields within the CP0_Wired and CP0_Config1 registers. Finally a definition for the CP0_Config5.SBRI bit allows KVM to initialise and allow modification of the guest version of the SBRI bit. Signed-off-by: James Hogan <james.hogan@imgtec.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
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