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2018-02-07arch-arm: Change function name for banked miscregsGiacomo Travaglini
This commit changes the function's name used for retrieving the index of a security banked register given the flatten index. This will avoid confusion with flattenRegId, which has a different purpose. Change-Id: I470ffb55916cb7fc9f78e071a7f2e609c1829f1a Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-on: https://gem5-review.googlesource.com/7982 Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-12-22arch,cpu: "virtualize" the TLB interface.Gabe Black
CPUs have historically instantiated the architecture specific version of the TLBs to avoid a virtual function call, making them a little bit more dependent on what the current ISA is. Some simple performance measurement, the x86 twolf regression on the atomic CPU, shows that there isn't actually any performance benefit, and if anything the simulator goes slightly faster (although still within margin of error) when the TLB functions are virtual. This change switches everything outside of the architectures themselves to use the generic BaseTLB type, and then inside the ISA for them to cast that to their architecture specific type to call into architecture specific interfaces. The ARM TLB needed the most adjustment since it was using non-standard translation function signatures. Specifically, they all took an extra "type" parameter which defaulted to normal, and translateTiming returned a Fault. translateTiming actually doesn't need to return a Fault because everywhere that consumed it just stored it into a structure which it then deleted(?), and the fault is stored in the Translation object when the translation is done. A little more work is needed to fully obviate the arch/tlb.hh header, so the TheISA::TLB type is still visible outside of the ISAs. Specifically, the TlbEntry type is used in the generic PageTable which lives in src/mem. Change-Id: I51b68ee74411f9af778317eff222f9349d2ed575 Reviewed-on: https://gem5-review.googlesource.com/6921 Maintainer: Gabe Black <gabeblack@google.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2017-12-05arm: Add CMO support for Non-Cacheable memoryNikos Nikoleris
Cache Maintainance operations to the point of coherence are treated as normal cahceable requests and clean and/or invalidate the caches of all PEs. Change-Id: Ia4a749c2318fe29c8601848b034b8315c4186c8a Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-on: https://gem5-review.googlesource.com/5056 Maintainer: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2017-05-09arm: Add support for memory-mapped m5opsAndreas Sandberg
Add support for a memory mapped m5op interface. When enabled, the TLB intercepts accesses in the 64KiB region designated by the ArmTLB.m5ops_base parameter. An access to this range maps to a specific m5op call. The upper 8 bits of the offset into the range denote the m5op function to call and the lower 8 bits denote the subfunction. Change-Id: I55fd8ac1afef4c3cc423b973870c9fe600a843a2 Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-on: https://gem5-review.googlesource.com/2964
2017-02-21arm: Blame the right instruction address on a Prefetch AbortNikos Nikoleris
CPU models (e.g., O3CPU) issue instruction fetches for the whole cache block rather than a specific instruction. Consequently the TLB lookups translate the cache block virtual address. When the TLB lookup fails, however, the Prefetch Abort must be raised for the PC of the instruction that caused the fault rather than for the address of the block. This change fixes the way we instantiate the PrefetchAbort faults to use the PC of the request rather the address of the instruction fetch request. Change-Id: I8e45549da1c3be55ad204a060029c95ce822a851 Reviewed-by: Curtis Dunham <curtis.dunham@arm.com> Reviewed-by: Rekai Gonzalez Alberquilla <rekai.gonzalezalberquilla@arm.com> Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
2016-11-09style: [patch 1/22] use /r/3648/ to reorganize includesBrandon Potter
2016-08-15cpu, arch: fix the type used for the request flagsNikos Nikoleris
Change-Id: I183b9942929c873c3272ce6d1abd4ebc472c7132 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
2016-08-02arm: Add TLBI instruction for stage 2 IPA'sDylan Johnson
This patch adds support for stage 2 TLBI instructions such as TLBI IPAS2E1_Xt. Change-Id: I0cd5e8055b0c1003e03439aa5183252f50ea0a88
2016-08-02arm: Fix stage 2 determination in table walkerDylan Johnson
We recompute if we are doing a stage 2 walk inside of the table walker but we have already figured it out in the tlb. Pass the information in to the walk instead of recomputing it. Change-Id: I39637ce99309b2ddbc30344d45ac9ebf6a203401
2016-08-02arm: Fix EL perceived at TLB for address translation instructionsDylan Johnson
During address translation instructions (such as AT S1E1R_Xt) the exception level can be different than the current exception level. This patch fixes how the TLB determines what EL to use during these instructions. Change-Id: Ia9ce229404de9e284bc1f7479fd2c580efd55f8f
2016-08-02arm: add stage2 translation supportDylan Johnson
Change-Id: I8f7c09c7ec3a97149ebebf4b21471b244e6cecc1
2016-07-11arm: Don't consult the TLB test iface for functional translationsAndreas Sandberg
Don't consult the TLB test interface for PA's returned by functional translations by the AT instruction. We implement this by chaning the ISA code to synthesize 0-length functional reads for the TLB lookup. The TLB then bypasses the final PA check in the tester if the size is zero. Change-Id: I2487b7f829cea88c37e229e9fc7a4543aced961b Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
2016-06-06sim: Call regStats of base-class as wellStephan Diestelhorst
We want to extend the stats of objects hierarchically and thus it is necessary to register the statistics of the base-class(es), as well. For now, these are empty, but generic stats will be added there. Patch originally provided by Akash Bagdia at ARM Ltd.
2016-06-02arm: refactor page table format determinationCurtis Dunham
In particular, when EL0 is in AArch32 but EL1 is AArch64, AArch64 memory translation must be used. This is essential for typical AArch64/32 interworking use cases.
2016-05-31arm: Correctly check translation mode (aarch64/aarch32)Andreas Sandberg
According to the ARM ARM (see AArch32.TranslateAddress in the pseudocode library), the TLB should be operating in aarch64 mode if the EL0 is aarch32 and EL1 is aarch64. This is currently not the case in gem5, which breaks 64/32 interprocessing. Update the check to match the reference manual. Change-Id: I6f1444d57c0e2eb5f8880f513f33a9197b7cb2ce Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Mitch Hayenga <mitch.hayenga@arm.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
2016-05-26arm: Fix incorrect TLB permission check in aarch32Andreas Sandberg
The TLB currently assumes that the pxn bit in an LPAE page descriptor disables execution from unprivileged mode. However, according to the architecture manual, this bit should disable execution from privileged modes. Update the TLB implementation to reflect this behavior. Change-Id: I7f1bb232d7a94a93fd601a9230223195ac952947 Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
2016-03-21arm: Refactor the TLB test interfaceAndreas Sandberg
Refactor the TLB and page table walker test interface to use a dynamic registration mechanism. Instead of patching a couple of empty methods to wire up a TLB tester, this change allows such testers to register themselves using the setTestInterface() method.
2016-02-06style: fix missing spaces in control statementsSteve Reinhardt
Result of running 'hg m5style --skip-all --fix-control -a'.
2015-09-30arm: Change TLB Software CachingMitch Hayenga
In ARM, certain variables are only updated when a necessary change is detected. Having 2 SMT threads share a TLB resulted in these not being updated as required. This patch adds a thread context identifer to assist in the invalidation of these variables.
2015-08-21arm, mem: Remove unused CLEAR_LL request flagAndreas Hansson
Cleaning up dead code. The CLREX stores zero directly to MISCREG_LOCKFLAG and so the request flag is no longer needed. The corresponding functionality in the cache tags is also removed.
2015-07-07sim: Refactor the serialization base classAndreas Sandberg
Objects that are can be serialized are supposed to inherit from the Serializable class. This class is meant to provide a unified API for such objects. However, so far it has mainly been used by SimObjects due to some fundamental design limitations. This changeset redesigns to the serialization interface to make it more generic and hide the underlying checkpoint storage. Specifically: * Add a set of APIs to serialize into a subsection of the current object. Previously, objects that needed this functionality would use ad-hoc solutions using nameOut() and section name generation. In the new world, an object that implements the interface has the methods serializeSection() and unserializeSection() that serialize into a named /subsection/ of the current object. Calling serialize() serializes an object into the current section. * Move the name() method from Serializable to SimObject as it is no longer needed for serialization. The fully qualified section name is generated by the main serialization code on the fly as objects serialize sub-objects. * Add a scoped ScopedCheckpointSection helper class. Some objects need to serialize data structures, that are not deriving from Serializable, into subsections. Previously, this was done using nameOut() and manual section name generation. To simplify this, this changeset introduces a ScopedCheckpointSection() helper class. When this class is instantiated, it adds a new /subsection/ and subsequent serialization calls during the lifetime of this helper class happen inside this section (or a subsection in case of nested sections). * The serialize() call is now const which prevents accidental state manipulation during serialization. Objects that rely on modifying state can use the serializeOld() call instead. The default implementation simply calls serialize(). Note: The old-style calls need to be explicitly called using the serializeOld()/serializeSectionOld() style APIs. These are used by default when serializing SimObjects. * Both the input and output checkpoints now use their own named types. This hides underlying checkpoint implementation from objects that need checkpointing and makes it easier to change the underlying checkpoint storage code.
2015-06-21arm: Cleanup arch headers to remove dma_device.hh dependencyAndreas Sandberg
Break the dependency on dma_device.hh by forward-declaring DmaPort in the relevant header.
2015-05-26arm: Make address translation faster with better cachingNathanael Premillieu
This patch adds better caching of the sys regs for AArch64, thus avoiding unnecessary calls to tc->readMiscReg(MISCREG_CPSR) in the non-faulting case.
2015-05-05arm: Relax ordering for some uncacheable accessesAndreas Sandberg
We currently assume that all uncacheable memory accesses are strictly ordered. Instead of always enforcing strict ordering, we now only enforce it if the required memory type is device memory or strongly ordered memory.
2015-05-05mem, cpu: Add a separate flag for strictly ordered memoryAndreas Sandberg
The Request::UNCACHEABLE flag currently has two different functions. The first, and obvious, function is to prevent the memory system from caching data in the request. The second function is to prevent reordering and speculation in CPU models. This changeset gives the order/speculation requirement a separate flag (Request::STRICT_ORDER). This flag prevents CPU models from doing the following optimizations: * Speculation: CPU models are not allowed to issue speculative loads. * Write combining: CPU models and caches are not allowed to merge writes to the same cache line. Note: The memory system may still reorder accesses unless the UNCACHEABLE flag is set. It is therefore expected that the STRICT_ORDER flag is combined with the UNCACHEABLE flag to prevent this behavior.
2015-05-05arm: Remove unnecessary boot uncachabilityAndreas Hansson
With the recent patches addressing how we deal with uncacheable accesses there is no longer need for the work arounds put in place to enforce certain sections of memory to be uncacheable during boot.
2015-03-02arm: Share a port for the two table walker objectsAndreas Hansson
This patch changes how the MMU and table walkers are created such that a single port is used to connect the MMU and the TLBs to the memory system. Previously two ports were needed as there are two table walker objects (stage one and stage two), and they both had a port. Now the port itself is moved to the Stage2MMU, and each TableWalker is simply using the port from the parent. By using the same port we also remove the need for having an additional crossbar joining the two ports before the walker cache or the L2. This simplifies the creation of the CPU cache topology in BaseCPU.py considerably. Moreover, for naming and symmetry reasons, the TLB walker port is connected through the stage-one table walker thus making the naming identical to x86. Along the same line, we use the stage-one table walker to generate the master id that is used by all TLB-related requests.
2014-12-23arm: Raise an alignment fault if a PC has illegal alignmentAndreas Sandberg
We currently don't handle unaligned PCs correctly. There is one check for unaligned PCs in the TLB when running in aarch64 mode, but this check does not cover cases where the CPU does not do a TLB lookup when decoding an instruction (e.g., a branch stays within the same cache line). Additionally, the Decoder class sometimes throws an assertion for unaligned PCs which breaks speculation. This changeset introduces a decoder fault bit field in the ExtMachInst structure. This field can be used to signal a decoder failure. If set, the decoder generates an internal gem5fault instruction instead of a normal instruction. This instruction in turns either panics (fault type PANIC), returns an PCAlignmentFault (fault type UNALIGNED, aarch64) or PrefetchAbort (fault type UNALIGNED, aarch32). The patch causes minor changes to the realview64 regressions, and a stats bump will follow.
2014-11-14arm: Fixes based on UBSan and static analysisAndreas Hansson
Another churn to clean up undefined behaviour, mostly ARM, but some parts also touching the generic part of the code base. Most of the fixes are simply ensuring that proper intialisation. One of the more subtle changes is the return type of the sign-extension, which is changed to uint64_t. This is to avoid shifting negative values (undefined behaviour) in the ISA code.
2014-10-29arm: Fix multi-system AArch64 boot w/caches.Ali Saidi
Automatically extract cpu release address from DTB file. Check SCTLR_EL1 to verify all caches are enabled.
2014-10-16arch: Use shared_ptr for all FaultsAndreas Hansson
This patch takes quite a large step in transitioning from the ad-hoc RefCountingPtr to the c++11 shared_ptr by adopting its use for all Faults. There are no changes in behaviour, and the code modifications are mostly just replacing "new" with "make_shared".
2014-10-16arm: Add TLB PMU probesAndreas Sandberg
This changeset adds probe points that can be used to implement PMU counters for TLB stats. The following probes are supported: * ArmISA::TLB::ppRefills / TLB Refills (TLB insertions)
2014-09-27arm: Fixed undefined behaviours identified by gccAndreas Hansson
This patch fixes the runtime errors highlighted by the undefined behaviour sanitizer. In the end there were two issues. First, when rotating an immediate, we ended up shifting an uint32_t by 32 in some cases. This case is fixed by checking for a rotation by 0 positions. Second, the Mrc15 and Mcr15 are operating on an IntReg and a MiscReg, but we used the type RegRegImmOp and passed a MiscRegIndex as an IntRegIndex. This issue is resolved by introducing a MiscRegRegImmOp and RegMiscRegImmOp with the appropriate types. With these fixes there are no runtime errors identified for the full ARM regressions.
2014-09-12style: Fix line continuation, especially in debug messagesAndrew Bardsley
This patch closes a number of space gaps in debug messages caused by the incorrect use of line continuation within strings. (There's also one consistency change to a similar, but correct, use of line continuation)
2014-05-09arch, arm: Preserve TLB bootUncacheability when switching CPUsGeoffrey Blake
The ARM TLBs have a bootUncacheability flag used to make some loads and stores become uncacheable when booting in FS mode. Later the flag is cleared to let those loads and stores operate as normal. When doing a takeOverFrom(), this flag's state is not preserved and is momentarily reset until the CPSR is touched. On single core runs this is a non-issue. On multi-core runs this can lead to crashes on the O3 CPU model from the following series of events: 1) takeOverFrom executed to switch from Atomic -> O3 2) All bootUncacheability flags are reset to true 3) Core2 tries to execute a load covered by bootUncacheability, it is flagged as uncacheable 4) Core2's load needs to replay due to a pipeline flush 3) Core1 core does an action on CPSR 4) The handling code for CPSR then checks all other cores to determine if bootUncacheability can be set to false 5) Asynchronously set bootUncacheability on all cores to false 6) Core2 replays load previously set as uncacheable and notices it is now flagged as cacheable, leads to a panic. This patch implements takeOverFrom() functionality for the ARM TLBs to preserve flag values when switching from atomic -> detailed.
2014-01-24arm: Add support for ARMv8 (AArch64 & AArch32)ARM gem5 Developers
Note: AArch64 and AArch32 interworking is not supported. If you use an AArch64 kernel you are restricted to AArch64 user-mode binaries. This will be addressed in a later patch. Note: Virtualization is only supported in AArch32 mode. This will also be fixed in a later patch. Contributors: Giacomo Gabrielli (TrustZone, LPAE, system-level AArch64, AArch64 NEON, validation) Thomas Grocutt (AArch32 Virtualization, AArch64 FP, validation) Mbou Eyole (AArch64 NEON, validation) Ali Saidi (AArch64 Linux support, code integration, validation) Edmund Grimley-Evans (AArch64 FP) William Wang (AArch64 Linux support) Rene De Jong (AArch64 Linux support, performance opt.) Matt Horsnell (AArch64 MP, validation) Matt Evans (device models, code integration, validation) Chris Adeniyi-Jones (AArch64 syscall-emulation) Prakash Ramrakhyani (validation) Dam Sunwoo (validation) Chander Sudanthi (validation) Stephan Diestelhorst (validation) Andreas Hansson (code integration, performance opt.) Eric Van Hensbergen (performance opt.) Gabe Black
2014-01-24mem: per-thread cache occupancy and per-block agesDam Sunwoo
This patch enables tracking of cache occupancy per thread along with ages (in buckets) per cache blocks. Cache occupancy stats are recalculated on each stat dump.
2013-10-31mem: Add privilege info to request classPrakash Ramrakhyani
This patch adds a flag in the request class that indicates if the request was made in privileged mode.
2013-06-03arch: Create a method to finalize physical addressesAndreas Sandberg
in the TLB Some architectures (currently only x86) require some fixing-up of physical addresses after a normal address translation. This is usually to remap devices such as the APIC, but could be used for other memory mapped devices as well. When running the CPU in a using hardware virtualization, we still need to do these address fix-ups before inserting the request into the memory system. This patch moves this patch allows that code to be used by such CPUs without doing full address translations.
2013-02-15arm: fix a page table walker issue where a page could be translated multiple ↵Mrinmoy Ghosh
times If multiple memory operations to the same page are miss the TLB they are all inserted into the page table queue and before this change could result in multiple uncessesary walks as well as duplicate enteries being inserted into the TLB.
2013-01-07arm: Invalidate cached TLB configuration in drainResumeAndreas Sandberg
Currently, we invalidate the cached miscregs in TLB::unserialize(). The intended use of the drainResume() method is to invalidate cached state and prepare the system to resume after a CPU handover or (un)serialization. This patch moves the TLB miscregs invalidation code to the drainResume() method to avoid surprising behavior.
2012-10-15Port: Add protocol-agnostic ports in the port hierarchyAndreas Hansson
This patch adds an additional level of ports in the inheritance hierarchy, separating out the protocol-specific and protocl-agnostic parts. All the functionality related to the binding of ports is now confined to use BaseMaster/BaseSlavePorts, and all the protocol-specific parts stay in the Master/SlavePort. In the future it will be possible to add other protocol-specific implementations. The functions used in the binding of ports, i.e. getMaster/SlavePort now use the base classes, and the index parameter is updated to use the PortID typedef with the symbolic InvalidPortID as the default.
2012-03-30MEM: Introduce the master/slave port sub-classes in C++William Wang
This patch introduces the notion of a master and slave port in the C++ code, thus bringing the previous classification from the Python classes into the corresponding simulation objects and memory objects. The patch enables us to classify behaviours into the two bins and add assumptions and enfore compliance, also simplifying the two interfaces. As a starting point, isSnooping is confined to a master port, and getAddrRanges to slave ports. More of these specilisations are to come in later patches. The getPort function is not getMasterPort and getSlavePort, and returns a port reference rather than a pointer as NULL would never be a valid return value. The default implementation of these two functions is placed in MemObject, and calls fatal. The one drawback with this specific patch is that it requires some code duplication, e.g. QueuedPort becomes QueuedMasterPort and QueuedSlavePort, and BusPort becomes BusMasterPort and BusSlavePort (avoiding multiple inheritance). With the later introduction of the port interfaces, moving the functionality outside the port itself, a lot of the duplicated code will disappear again.
2012-01-31Merge with head, hopefully the last time for this batch.Gabe Black
2012-01-31CheckerCPU: Re-factor CheckerCPU to be compatible with current gem5Geoffrey Blake
Brings the CheckerCPU back to life to allow FS and SE checking of the O3CPU. These changes have only been tested with the ARM ISA. Other ISAs potentially require modification.
2012-01-29Implement Ali's review feedback.Gabe Black
Try to decrease indentation, and remove some redundant FullSystem checks.
2011-11-02SE/FS: Get rid of FULL_SYSTEM in the ARM ISA.Gabe Black
2011-10-16ARM: Turn on the page table walker on ARM in SE mode.Gabe Black
2011-09-13ARM: update TLB to set request packet ASID fieldDaniel Johnson
2011-08-19ARM: Mark some variables uncacheable until boot all CPUs are enabled.Ali Saidi
There are a set of locations is the linux kernel that are managed via cache maintence instructions until all processors enable their MMUs & TLBs. Writes to these locations are manually flushed from the cache to main memory when the occur so that cores operating without their MMU enabled and only issuing uncached accesses can receive the correct data. Unfortuantely, gem5 doesn't support any kind of software directed maintence of the cache. Until such time as that support exists this patch marks the specific cache blocks that need to be coherent as non-cacheable until all CPUs enable their MMU and thus allows gem5 to boot MP systems with caches enabled (a requirement for booting an O3 cpu and thus an O3 CPU regression).