c5c9f48e3f
Previously, all components assume the info in arch/riscv/regs/misc.hh to be the single source of CSR info. That will however make adding non-standard CSRs difficult as all those CSRs will need to go into the same header & data structure and might conflict with each other. In this CL, we add two new functions to the ISA class that provide information about CSR. The rationale is that, the ISA class is already the owner of CSR data, so it'll also be in a better position to provide necessary CSR metadata. With the change, we can create two CPU models with slightly different custom CSRs easily by creating two derived RiscvISA classes and overriding the two functions. We assume that, any customized CSR set is still compatible with standard CSRs, so we could still utilize the same global map if only standard CSRs are accessed in the use case. Note that this does not necessarily mean you cannot or should not add your customize CSRs into the MiscRegIndex enum. You'll usually still required to do that to give each CSR an unique id. However, the ability to override CSRDataMap/CSRMaskMap provide an opportunity to remap how the CSR index encoded in the instruction maps to CSR, and also give you a chance to make the read/write logic of certain custom CSRs different. Change-Id: I168188bdb1baed11cb3e217eb021f289a13bb036 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/62891 Reviewed-by: Jason Lowe-Power <power.jg@gmail.com> Maintainer: Jason Lowe-Power <power.jg@gmail.com> Tested-by: kokoro <noreply+kokoro@google.com>
This is the gem5 simulator. The main website can be found at http://www.gem5.org A good starting point is http://www.gem5.org/about, and for more information about building the simulator and getting started please see http://www.gem5.org/documentation and http://www.gem5.org/documentation/learning_gem5/introduction. To build gem5, you will need the following software: g++ or clang, Python (gem5 links in the Python interpreter), SCons, zlib, m4, and lastly protobuf if you want trace capture and playback support. Please see http://www.gem5.org/documentation/general_docs/building for more details concerning the minimum versions of these tools. Once you have all dependencies resolved, type 'scons build/<CONFIG>/gem5.opt' where CONFIG is one of the options in build_opts like ARM, NULL, MIPS, POWER, SPARC, X86, Garnet_standalone, etc. This will build an optimized version of the gem5 binary (gem5.opt) with the the specified configuration. See http://www.gem5.org/documentation/general_docs/building for more details and options. The main source tree includes these subdirectories: - build_opts: pre-made default configurations for gem5 - build_tools: tools used internally by gem5's build process. - configs: example simulation configuration scripts - ext: less-common external packages needed to build gem5 - include: include files for use in other programs - site_scons: modular components of the build system - src: source code of the gem5 simulator - system: source for some optional system software for simulated systems - tests: regression tests - util: useful utility programs and files To run full-system simulations, you may need compiled system firmware, kernel binaries and one or more disk images, depending on gem5's configuration and what type of workload you're trying to run. Many of those resources can be downloaded from http://resources.gem5.org, and/or from the git repository here: https://gem5.googlesource.com/public/gem5-resources/ If you have questions, please send mail to gem5-users@gem5.org Enjoy using gem5 and please share your modifications and extensions.