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| * | MIPS: Respect the FCSR exception mask for `si_code'Maciej W. Rozycki2015-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Respect the FCSR exception mask when interpreting the IEEE 754 exception condition to report with SIGFPE in `si_code', so as not to use one that has been masked where a different one set in parallel caused the FPE hardware exception to trigger. As per the IEEE Std 754 the Inexact exception can happen together with Overflow or Underflow. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9703/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| * | MIPS: Correct FP ISA requirementsMaciej W. Rozycki2015-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Correct ISA requirements for floating-point instructions: * the CU3 exception signifies a real COP3 instruction in MIPS I & II, * the BC1FL and BC1TL instructions are not supported in MIPS I, * the SQRT.fmt instructions are indeed supported in MIPS II, * the LDC1 and SDC1 instructions are indeed supported in MIPS32r1, * the CEIL.W.fmt, FLOOR.W.fmt, ROUND.W.fmt and TRUNC.W.fmt instructions are indeed supported in MIPS32, * the CVT.L.fmt and CVT.fmt.L instructions are indeed supported in MIPS32r2 and MIPS32r6, * the CEIL.L.fmt, FLOOR.L.fmt, ROUND.L.fmt and TRUNC.L.fmt instructions are indeed supported in MIPS32r2 and MIPS32r6, * the RSQRT.fmt and RECIP.fmt instructions are indeed supported in MIPS64r1, Also simplify conditionals for MIPS III and MIPS IV FPU instructions and the handling of the MOVCI minor opcode. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9700/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| * | MIPS: Fix BREAK code interpretation heuristicsMaciej W. Rozycki2015-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Do not lose the other half of the BREAK code where there is an upper half. This is so that e.g. `BREAK 7, 7' is not interpreted as a divide by zero trap, while `BREAK 0, 7' or `BREAK 7, 0' still are. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9697/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| * | MIPS: BREAK instruction interpretation correctionsMaciej W. Rozycki2015-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the missing microMIPS BREAK16 instruction code interpretation and reshape code removing instruction fetching duplication and the separate call to `do_trap_or_bp' in the MIPS16 path. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9696/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| * | MIPS: Correct MIPS16 BREAK code interpretationMaciej W. Rozycki2015-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Correct the interpretation of the immediate MIPS16 BREAK instruction code embedded in the instruction word across bits 10:5 rather than 11:6 as current code implies, fixing the interpretation of integer overflow and divide by zero traps. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9695/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| * | MIPS: Normalise code flow in the CpU exception handlerMaciej W. Rozycki2015-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Changes applied to `do_cpu' over time reduced the use of the SIGILL issued with `force_sig' at the end to a single CU3 case only in the switch statement there. Move that `force_sig' call over to right where required then and toss out the pile of gotos now not needed to skip over the call, replacing them with regular breaks out of the switch. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9683/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| * | MIPS: Reindent R6 RI exception emulationMaciej W. Rozycki2015-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fold a nested `if' statement for the R6 case in `do_ri' into its containing `if' block, removing excessive indentation causing code to extend beyond 79 columns. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9679/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| * | MIPS: Correct the comment for FPU emulator trapsMaciej W. Rozycki2015-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adjust the explanatory comment for FPU emulator traps according to ba3049ed [MIPS: Switch FPU emulator trap to BREAK instruction.]; originally coming from `do_ade'. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9672/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| * | MIPS: Read CPU IRQ line that FDC to routed toJames Hogan2015-03-31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Read the CPU IRQ line reportedly used for the Fast Debug Channel (FDC) interrupt from the IntCtl register and store it in cp0_fdc_irq where platform implementations of the new weak platform function get_c0_fdc_int() can refer to it. [ralf@linux-mips.org: Fixed conflict.] Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Cc: James Hogan <james.hogan@imgtec.com> Patchwork: https://patchwork.linux-mips.org/patch/9140/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| * | MIPS: Allow shared IRQ for timer & perf counterJames Hogan2015-03-31
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before release 2 of the architecture there weren't separate interrupt pending bits for the local CPU interrupts (timer & perf counter overflow), so when they were connected to the same interrupt line the timer handler had to call the performance counter handler before knowing whether a timer interrupt was actually pending. Now another CPU local interrupt, for the Fast Debug Channel (FDC), can also be routed to an arbitrary interrupt line. It isn't scalable to keep adding cross-calls between handlers for these cases of shared interrupt lines, especially since the FDC could in theory share its interrupt line with the performance counter, timer, or both. Fortunately since release 2 of the architecture separate interrupt pending bits do exist in the Cause register. This allows local interrupts which share an interrupt line to have separate handlers using IRQF_SHARED. Unfortunately they can't easily have their own irqchip as there is no generic way to individually mask them. Enable this sharing to happen by removing the special case for when the perf count shares an IRQ with the timer. cp0_perfcount_irq and cp0_compare_irq can then be set to the same value with shared interrupt handlers registered for both of them. Pre-R2 code should be unaffected. cp0_perfcount_irq will always be -1 and the timer handler will contnue to call into the perf counter handler. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/9131/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* | MIPS: Clear [MSA]FPE CSR.Cause after notify_die()James Hogan2015-03-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When handling floating point exceptions (FPEs) and MSA FPEs the Cause bits of the appropriate control and status register (FCSR for FPEs and MSACSR for MSA FPEs) are read and cleared before enabling interrupts, presumably so that it doesn't have to go through the pain of restoring those bits if the process is pre-empted, since writing those bits would cause another immediate exception while still in the kernel. The bits aren't normally ever restored again, since userland never expects to see them set. However for virtualisation it is necessary for the kernel to be able to restore these Cause bits, as the guest may have been interrupted in an FP exception handler but before it could read the Cause bits. This can be done by registering a die notifier, to get notified of the exception when such a value is restored, and if the PC was at the instruction which is used to restore the guest state, the handler can step over it and continue execution. The Cause bits can then remain set without causing further exceptions. For this to work safely a few changes are made: - __build_clear_fpe and __build_clear_msa_fpe no longer clear the Cause bits, and now return from exception level with interrupts disabled instead of enabled. - do_fpe() now clears the Cause bits and enables interrupts after notify_die() is called, so that the notifier can chose to return from exception without this happening. - do_msa_fpe() acts similarly, but now actually makes use of the second argument (msacsr) and calls notify_die() with the new DIE_MSAFP, allowing die notifiers to be informed of MSA FPEs too. Signed-off-by: James Hogan <james.hogan@imgtec.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
* | MIPS: Ensure FCSR cause bits are clear after invoking FPU emulatorPaul Burton2015-03-27
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When running the emulator to handle an instruction that raised an FP unimplemented operation exception, the FCSR cause bits were being cleared. This is done to ensure that the kernel does not take an FP exception when later restoring FP context to registers. However, this was not being done when the emulator is invoked in response to a coprocessor unusable exception. This happens in 2 cases: - There is no FPU present in the system. In this case things were OK, since the FP context is never restored to hardware registers and thus no FP exception may be raised when restoring FCSR. - The FPU could not be configured to the mode required by the task. In this case it would be possible for the emulator to set cause bits which are later restored to hardware if the task migrates to a CPU whose associated FPU does support its mode requirements, or if the tasks FP mode requirements change. Consistently clear the cause bits after invoking the emulator, by moving the clearing to process_fpemu_return and ensuring this is always called before the tasks FP context is restored. This will make it easier to catch further paths invoking the emulator in future, as will be introduced in further patches. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9165/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linusLinus Torvalds2015-02-21
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull MIPS updates from Ralf Baechle: "This is the main pull request for MIPS: - a number of fixes that didn't make the 3.19 release. - a number of cleanups. - preliminary support for Cavium's Octeon 3 SOCs which feature up to 48 MIPS64 R3 cores with FPU and hardware virtualization. - support for MIPS R6 processors. Revision 6 of the MIPS architecture is a major revision of the MIPS architecture which does away with many of original sins of the architecture such as branch delay slots. This and other changes in R6 require major changes throughout the entire MIPS core architecture code and make up for the lion share of this pull request. - finally some preparatory work for eXtendend Physical Address support, which allows support of up to 40 bit of physical address space on 32 bit processors" [ Ahh, MIPS can't leave the PAE brain damage alone. It's like every CPU architect has to make that mistake, but pee in the snow by changing the TLA. But whether it's called PAE, LPAE or XPA, it's horrid crud - Linus ] * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (114 commits) MIPS: sead3: Corrected get_c0_perfcount_int MIPS: mm: Remove dead macro definitions MIPS: OCTEON: irq: add CIB and other fixes MIPS: OCTEON: Don't do acknowledge operations for level triggered irqs. MIPS: OCTEON: More OCTEONIII support MIPS: OCTEON: Remove setting of processor specific CVMCTL icache bits. MIPS: OCTEON: Core-15169 Workaround and general CVMSEG cleanup. MIPS: OCTEON: Update octeon-model.h code for new SoCs. MIPS: OCTEON: Implement DCache errata workaround for all CN6XXX MIPS: OCTEON: Add little-endian support to asm/octeon/octeon.h MIPS: OCTEON: Implement the core-16057 workaround MIPS: OCTEON: Delete unused COP2 saving code MIPS: OCTEON: Use correct instruction to read 64-bit COP0 register MIPS: OCTEON: Save and restore CP2 SHA3 state MIPS: OCTEON: Fix FP context save. MIPS: OCTEON: Save/Restore wider multiply registers in OCTEON III CPUs MIPS: boot: Provide more uImage options MIPS: Remove unneeded #ifdef __KERNEL__ from asm/processor.h MIPS: ip22-gio: Remove legacy suspend/resume support mips: pci: Add ifdef around pci_proc_domain ...
| * MIPS: Make use of the ERETNC instruction on MIPS R6Markos Chandras2015-02-17
| | | | | | | | | | | | | | | | | | | | | | | | The ERETNC instruction, introduced in MIPS R5, is similar to the ERET one, except it does not clear the LLB bit in the LLADDR register. This feature is necessary to safely emulate R2 LL/SC instructions. However, on context switches, we need to clear the LLAddr/LLB bit in order to make sure that an SC instruction from the new thread will never succeed if it happens to interrupt an LL operation on the same address from the previous thread. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
| * MIPS: kernel: mips-r2-to-r6-emul: Add R2 emulator for MIPS R6Leonid Yegoshin2015-02-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | MIPS R6 removed quite a few R2 instructions. However, there is plenty of <R6 userland code so we add an in-kernel emulator so we can still be able to execute all R2 userland out there. The emulator comes with a handy debugfs under /mips/ directory (r2-emul-stats) to provide some basic statistics of the instructions that are being emulated. Below are some statistics from booting a minimal buildroot image: Instruction Total BDslot ------------------------------ movs 236969 0 hilo 56686 0 muls 55279 0 divs 10941 0 dsps 0 0 bops 1 0 traps 0 0 fpus 0 0 loads 214981 17 stores 103364 0 llsc 56898 0 dsemul 150418 0 jr 370158 bltzl 43 bgezl 1594 bltzll 0 bgezll 0 bltzal 39 bgezal 39 beql 14503 bnel 138741 blezl 0 bgtzl 3988 Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
| * MIPS: kernel: traps: Add MIPS R6 related definitionsLeonid Yegoshin2015-02-17
| | | | | | | | | | | | | | | | Add MIPS R6 support to cache and ftlb exceptions, as well as to the hwrena and ebase register configuration. Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
| * MIPS: Add cases for CPU_QEMU_GENERICLeonid Yegoshin2015-02-16
| | | | | | | | | | | | | | Add a CPU_QEMU_GENERIC case to various switch statements. Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
| * MIPS,prctl: add PR_[GS]ET_FP_MODE prctl options for MIPSPaul Burton2015-02-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Userland code may be built using an ABI which permits linking to objects that have more restrictive floating point requirements. For example, userland code may be built to target the O32 FPXX ABI. Such code may be linked with other FPXX code, or code built for either one of the more restrictive FP32 or FP64. When linking with more restrictive code, the overall requirement of the process becomes that of the more restrictive code. The kernel has no way to know in advance which mode the process will need to be executed in, and indeed it may need to change during execution. The dynamic loader is the only code which will know the overall required mode, and so it needs to have a means to instruct the kernel to switch the FP mode of the process. This patch introduces 2 new options to the prctl syscall which provide such a capability. The FP mode of the process is represented as a simple bitmask combining a number of mode bits mirroring those present in the hardware. Userland can either retrieve the current FP mode of the process: mode = prctl(PR_GET_FP_MODE); or modify the current FP mode of the process: err = prctl(PR_SET_FP_MODE, new_mode); Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: Matthew Fortune <matthew.fortune@imgtec.com> Cc: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/8899/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* | MIPS: traps: Fix inline asm ctc1 missing .set hardfloatJames Hogan2015-01-30
|/ | | | | | | | | | | | | | | | | | | | | | | | Commit 842dfc11ea9a ("MIPS: Fix build with binutils 2.24.51+") in v3.18 enabled -msoft-float and sprinkled ".set hardfloat" where necessary to use FP instructions. However it missed enable_restore_fp_context() which since v3.17 does a ctc1 with inline assembly, causing the following assembler errors on Mentor's 2014.05 toolchain: {standard input}: Assembler messages: {standard input}:2913: Error: opcode not supported on this processor: mips32r2 (mips32r2) `ctc1 $2,$31' scripts/Makefile.build:257: recipe for target 'arch/mips/kernel/traps.o' failed Fix that to use the new write_32bit_cp1_register() macro so that ".set hardfloat" is automatically added when -msoft-float is in use. Fixes 842dfc11ea9a ("MIPS: Fix build with binutils 2.24.51+") Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: <stable@vger.kernel.org> # 3.18+, depends on "MIPS: mipsregs.h: Add write_32bit_cp1_register()" Patchwork: https://patchwork.linux-mips.org/patch/9173/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: traps: Dump the PageGrain and Wired registers on MCMarkos Chandras2014-11-24
| | | | | | | | | | They can be useful to determine how the MMU is configured on a MC exception. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/8401/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: traps: Dump the HTW registers on a MC exceptionMarkos Chandras2014-11-24
| | | | | | | | | The HTW registers can be useful to debug a MC exception. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/8400/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: traps: Replace printk with pr_err for MC exceptionsMarkos Chandras2014-11-24
| | | | | | | | | printk should not be used without a KERN_ facility level Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/8399/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Support for hybrid FPRsPaul Burton2014-11-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Hybrid FPRs is a scheme where scalar FP registers are 64b wide, but accesses to odd indexed single registers use bits 63:32 of the preceeding even indexed 64b register. In this mode all FP code except that built for the plain FP64 ABI can execute correctly. Most notably a combination of FP64A & FP32 code can execute correctly, allowing for existing FP32 binaries to be linked with new FP64A binaries that can make use of 64 bit FP & MSA. Hybrid FPRs are implemented by setting both the FR & FRE bits, trapping & emulating single precision FP instructions (via Reserved Instruction exceptions) whilst allowing others to execute natively. It therefore has a penalty in terms of execution speed, and should only be used when no fully native mode can be. As more binaries are recompiled to use either the FPXX or FP64(A) ABIs, the need for hybrid FPRs should diminish. However in the short to mid term it allows for a gradual transition towards that world, rather than a complete ABI break which is not feasible for some users & not desirable for many. A task will be executed using the hybrid FPR scheme when its TIF_HYBRID_FPREGS flag is set & TIF_32BIT_FPREGS is clear. A further patch will set the flags as necessary, this patch simply adds the infrastructure necessary for the hybrid FPR mode to work. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/7683/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: disable preemption whilst initialising MSAPaul Burton2014-08-01
| | | | | | | | | | | | Preemption must be disabled throughout the process of enabling the FPU, enabling MSA & initialising the vector registers. Without doing so it is possible to lose the FPU or MSA whilst initialising them causing that initialisation to fail. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7307/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: fix MSA context for tasks which don't use FP firstPaul Burton2014-08-01
| | | | | | | | | | | | If a task does not execute scalar FP instructions prior to using MSA then the flags indicating that the task has live MSA context were not being set. The upper 64b of each vector register would then be lost upon the tasks first context switch after using MSA. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7500/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: init upper 64b of vector registers when MSA is first usedPaul Burton2014-08-01
| | | | | | | | | | | | | | | | | | | 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 <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7497/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: preserve scalar FP CSR when switching vector contextPaul Burton2014-08-01
| | | | | | | | | | | | | | Switching the vector context implicitly saves & restores the state of the aliased scalar FP data registers, however the scalar FP control & status register is distinct from the MSA control & status register. In order to allow scalar FP to function correctly in programs using MSA, the scalar CSR needs to be saved & restored along with the MSA vector context. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7301/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Use dedicated exception handler if CPU supports RI/XI exceptionsLeonid Yegoshin2014-08-01
| | | | | | | | | | | | | Use the regular tlb_do_page_fault_0 (no write) handler to handle the RI and XI exceptions. Also skip the RI/XI validation check on TLB load handler since it's redundant when the CPU has unique RI/XI exceptions. Singed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7339/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* Merge branch '3.15-fixes' into mips-for-linux-nextRalf Baechle2014-06-04
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| * MIPS: Call find_vma with the mmap_sem heldDavidlohr Bueso2014-06-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Performing vma lookups without taking the mm->mmap_sem is asking for trouble. While doing the search, the vma in question can be modified or even removed before returning to the caller. Take the lock (exclusively) in order to avoid races while iterating through the vmacache and/or rbtree. Updates two functions: - process_fpemu_return() - cteon_flush_cache_sigtramp() Signed-off-by: Davidlohr Bueso <davidlohr@hp.com> Tested-by: Andreas Herrmann <andreas.herrmann@caviumnetworks.com> Cc: linux-mips@linux-mips.org Cc: akpm@linux-foundation.org Cc: zeus@gnu.org Cc: aswin@hp.com Cc: davidlohr@hp.com Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Patchwork: http://patchwork.linux-mips.org/patch/6811/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| * MIPS: Fix typo when reporting cache and ftlb errors for ImgTec coresMarkos Chandras2014-05-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduced by the following two commits: 75b5b5e0a262790fa11043fe45700499c7e3d818 "MIPS: Add support for FTLBs" 6de20451857ed14a4eecc28d08f6de5925d1cf96 "MIPS: Add printing of ES bit for Imgtec cores when cache error occurs" Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Reported-by: Matheus Almeida <Matheus.Almeida@imgtec.com> Cc: linux-mips@linux-mips.org Cc: Markos Chandras <markos.chandras@imgtec.com> Cc: stable@vger.kernel.org # v3.14+ Patchwork: https://patchwork.linux-mips.org/patch/6980/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* | Merge branch 'wip-mips-pm' of https://github.com/paulburton/linux into ↵Ralf Baechle2014-05-29
|\ \ | | | | | | | | | mips-for-linux-next
| * | MIPS: traps: Add CPU PM callback for trap configurationJames Hogan2014-05-02
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | Implement a CPU power management callback for restoring trap related CPU configuration after CPU power up from a low power state. The following state is restored: - Status register - HWREna register - Exception vector configuration registers - Context/XContext register Signed-off-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Paul Burton <paul.burton@imgtec.com>
* / MIPS: MT: Remove SMTC supportRalf Baechle2014-05-23
|/ | | | | | | | | | | | | | | 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>
* MIPS: traps: Set correct address limit for breakpoints and trapsLeonid Yegoshin2014-03-26
| | | | | | | | | | When a breakpoint or trap happens when operating in kernel mode but on users behalf (eg syscall) it is necessary to change the address limit to KERNEL_DS so any address checking can be bypassed and print the correct stack trace. Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
* MIPS: kernel: traps: Whitespace clean upMarkos Chandras2014-03-26
| | | | Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
* MIPS: Add cases for CPU_P5600James Hogan2014-03-26
| | | | | | | | | | | Add a CPU_P5600 case to various switch statements, doing the same thing as for CPU_PROAPTIV. Signed-off-by: James Hogan <james.hogan@imgtec.com> Reviewed-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6408/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Dumb MSA FP exception handlerPaul Burton2014-03-26
| | | | | | | | | | | | | This patch adds a simple handler for MSA FP exceptions which delivers a SIGFPE to the running task. In the future it should probably be extended to re-execute the instruction with the MSACSR.NX bit set in order to generate results for any elements which did not cause an exception before delivering the SIGFPE signal. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6432/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Basic MSA context switching supportPaul Burton2014-03-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds support for context switching the MSA vector registers. These 128 bit vector registers are aliased with the FP registers - an FP register accesses the least significant bits of the vector register with which it is aliased (ie. the register with the same index). Due to both this & the requirement that the scalar FPU must be 64-bit (FR=1) if enabled at the same time as MSA the kernel will enable MSA & scalar FP at the same time for tasks which use MSA. If we restore the MSA vector context then we might as well enable the scalar FPU since the reason it was left disabled was to allow for lazy FP context restoring - but we just restored the FP context as it's a subset of the vector context. If we restore the FP context and have previously used MSA then we have to restore the whole vector context anyway (see comment in enable_restore_fp_context for details) so similarly we might as well enable MSA. Thus if a task does not use MSA then it will continue to behave as without this patch - the scalar FP context will be saved & restored as usual. But if a task executes an MSA instruction then it will save & restore the vector context forever more. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6431/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Add 1074K CPU support explicitly.Steven J. Hill2014-03-06
| | | | | | | | | | | | The 1074K is a multiprocessing coherent processing system (CPS) based on modified 74K cores. This patch makes the 1074K an actual unique CPU type, instead of a 74K derivative, which it is not. Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com> Reviewed-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6389/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Add support for interAptiv coresLeonid Yegoshin2014-01-22
| | | | | | | | | | | | | | | The interAptiv is a power-efficient multi-core microprocessor for use in system-on-chip (SoC) applications. The interAptiv combines a multi-threading pipeline with a coherence manager to deliver improved computational throughput and power efficiency. The interAptiv can contain one to four MIPS32R3 interAptiv cores, system level coherence manager with L2 cache, optional coherent I/O port, and optional floating point unit. Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Signed-off-by: John Crispin <blogic@openwrt.org> Patchwork: http://patchwork.linux-mips.org/patch/6163/
* MIPS: Add support for FTLBsLeonid Yegoshin2014-01-22
| | | | | | | | | | | | | | The Fixed Page Size TLB (FTLB) is a set-associative dual entry TLB. Its purpose is to reduce the number of TLB misses by increasing the effective TLB size and keep the implementation complexity to minimum levels. A supported core can have both VTLB and FTLB. Reviewed-by: James Hogan <james.hogan@imgtec.com> Reviewed-by: Paul Burton <paul.burton@imgtec.com> Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Signed-off-by: John Crispin <blogic@openwrt.org> Patchwork: http://patchwork.linux-mips.org/patch/6139/
* MIPS: Add support for the proAptiv coresLeonid Yegoshin2014-01-22
| | | | | | | | | | | | | | | | The proAptiv Multiprocessing System is a power efficient multi-core microprocessor for use in system-on-chip (SoC) applications. The proAptiv Multiprocessing System combines a deep pipeline with multi-issue out of order execution for improved computational throughput. The proAptiv Multiprocessing System can contain one to six MIPS32r3 proAptiv cores, system level coherence manager with L2 cache, optional coherent I/O port, and optional floating point unit. Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Signed-off-by: John Crispin <blogic@openwrt.org> Patchwork: http://patchwork.linux-mips.org/patch/6134/
* MIPS: Add printing of ES bit for Imgtec cores when cache error occurs.Leonid Yegoshin2014-01-22
| | | | | | | | | | | The cacheer register is always implemented in the same way in the MIPS32r2 Imgtec cores so print the ES bit when an cache error occurs. Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Signed-off-by: John Crispin <blogic@openwrt.org> Patchwork: http://patchwork.linux-mips.org/patch/6041/
* MIPS: Support for 64-bit FP with O32 binariesPaul Burton2014-01-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | CPUs implementing MIPS32 R2 may include a 64-bit FPU, just as MIPS64 CPUs do. In order to preserve backwards compatibility a 64-bit FPU will act like a 32-bit FPU (by accessing doubles from the least significant 32 bits of an even-odd pair of FP registers) when the Status.FR bit is zero, again just like a mips64 CPU. The standard O32 ABI is defined expecting a 32-bit FPU, however recent toolchains support use of a 64-bit FPU from an O32 MIPS32 executable. When an ELF executable is built to use a 64-bit FPU a new flag (EF_MIPS_FP64) is set in the ELF header. With this patch the kernel will check the EF_MIPS_FP64 flag when executing an O32 binary, and set Status.FR accordingly. The addition of O32 64-bit FP support lessens the opportunity for optimisation in the FPU emulator, so a CONFIG_MIPS_O32_FP64_SUPPORT Kconfig option is introduced to allow this support to be disabled for those that don't require it. Inspired by an earlier patch by Leonid Yegoshin, but implemented more cleanly & correctly. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: Paul Burton <paul.burton@imgtec.com> Patchwork: https://patchwork.linux-mips.org/patch/6154/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: traps: Reformat notify_die invocations to 80 columns.Ralf Baechle2013-10-29
| | | | Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Print correct PC in trace dump after NMI exceptionLeonid Yegoshin2013-10-29
| | | | | | | | | | | | | | | | | | | An NMI exception delivered from YAMON delivers the PC in ErrorPC instead of EPC. It's also necessary to clear the Status.BEV bit for the page fault exception handler to work properly. [ralf@linux-mips: Let the assembler do the loading of the mask value rather than the convoluted explicit %hi/%lo manual relocation sequence from the original patch.] Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6035/ Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Markos Chandras <markos.chandras@imgtec.com> Patchwork: https://patchwork.linux-mips.org/patch/6084/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Remove bogus BUG_ON()Markos Chandras2013-10-29
| | | | | | | | | | | | Checking for n<0 && n>9 makes no sense because it can never be true. Moreover, we can have up to 64 vectored interrupts so BUG_ON(n>9) was wrong anyway. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Acked-by: Steven J. Hill <Steven.Hill@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/5909/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Optimize current_cpu_type() for better code.Ralf Baechle2013-09-17
| | | | | | | | | | | | | o Move current_cpu_type() to a separate header file o #ifdefing on supported CPU types lets modern GCC know that certain code in callers may be discarded ideally turning current_cpu_type() into a function returning a constant. o Use current_cpu_type() rather than direct access to struct cpuinfo_mips. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Cc: Steven J. Hill <Steven.Hill@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/5833/
* Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linusLinus Torvalds2013-07-19
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull MIPS fixes from Ralf Baechle: "MIPS fixes for 3.11. Half of then is for Netlogic the remainder touches things across arch/mips. Nothing really dramatic and by rc1 standards MIPS will be in fairly good shape with this applied. Tested by building all MIPS defconfigs of which with this pull request four platforms won't build. And yes, it boots also on my favorite test systems" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: MIPS: kvm: Kconfig: Drop HAVE_KVM dependency from VIRTUALIZATION MIPS: Octeon: Fix DT pruning bug with pip ports MIPS: KVM: Mark KVM_GUEST (T&E KVM) as BROKEN_ON_SMP MIPS: tlbex: fix broken build in v3.11-rc1 MIPS: Netlogic: Add XLP PIC irqdomain MIPS: Netlogic: Fix USB block's coherent DMA mask MIPS: tlbex: Fix typo in r3000 tlb store handler MIPS: BMIPS: Fix thinko to release slave TP from reset MIPS: Delete dead invocation of exception_exit().