This patch adds an extra layer to the pyfdt library such that usage
gets easier and device tree nodes can be specified in less code,
without limiting original usage. Note to not import both the pyfdt
and fdthelper in the same namespace (but generally fdthelper is all
you need, because it supplies the same classes even when they are not
extended in any way)
Also, this patch lays out the primary functionality for generating a
device tree, where every SimObject gets an empty generateDeviceTree
method and ArmSystems loop over their children in an effort to merge
all the nodes. Devices are implemented in other patches.
Change-Id: I4d0a0666827287fe42e18447f19acab4dc80cc49
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5962
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
This patch adds support for cache flushing instructions in x86.
It piggybacks on support for similar instructions in arm ISA
added by Nikos Nikoleris. I have tested each instruction using
microbenchmarks.
Change-Id: I72b6b8dc30c236a21eff7958fa231f0663532d7d
Reviewed-on: https://gem5-review.googlesource.com/7401
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
Rather than store the actual TLB entry that corresponds to a mapping,
we can just store some abstracted information (address, a few flags)
and then let the caller turn that into the appropriate entry. There
could potentially be some small amount of overhead from creating
entries vs. storing them and just installing them, but it's likely
pretty minimal since that only happens on a TLB miss (ideally rare),
and, if it is problematic, there could be some preallocated TLB
entries which are just minimally filled in as necessary.
This has the nice effect of finally making the page tables ISA
agnostic.
Change-Id: I11e630f60682f0a0029b0683eb8ff0135fbd4317
Reviewed-on: https://gem5-review.googlesource.com/7350
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
The new version extracts all the x86 specific aspects of the class,
and builds the interface around a variable collection of template
arguments which are classes that represent the different levels of the
page table. The multilevel page table class is now much more ISA
independent.
Change-Id: Id42e168a78d0e70f80ab2438480cb6e00a3aa636
Reviewed-on: https://gem5-review.googlesource.com/7347
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>
Use the system object to allocate physical memory instead of manually
placing certain structures and then forcing the system to start other
allocations after them in physical memory.
Change-Id: Ie18c81645c3b648c64a6d7a649a0e50f7028f344
Reviewed-on: https://gem5-review.googlesource.com/7346
Maintainer: Gabe Black <gabeblack@google.com>
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
This avoids having a copy in the lookup function itself, and the
declaration of a lot of temporary TLB entry pointers in callers. The
gpu TLB seems to have had the most dependence on the original signature
of the lookup function, partially because it was relying on a somewhat
unsafe copy to a TLB entry using a base class pointer type.
Change-Id: I8b1cf494468163deee000002d243541657faf57f
Reviewed-on: https://gem5-review.googlesource.com/7343
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
The ARM types.hh file defined an STL style hash structure to operate
on the ExtMachInst, but it referred to the underlying storage type
using internal typedefs in the BitUnion types. To avoid having to do
that, this change adds a hash structure to bitunion.hh which will work
on any BitUnion, and gets rid of the ARM ExtMachInst version.
Change-Id: I7c1c84d61b59061fec98abaaeab6becd06537dee
Reviewed-on: https://gem5-review.googlesource.com/7204
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>
They are now oriented around a class which makes it easy to provide
custom setter/getter functions which let you set or read bits in an
arbitrary way.
Future additions may add the ability to add custom bitfield methods,
and index-able bitfields.
Change-Id: Ibd6d4d9e49107490f6dad30a4379a8c93bda9333
Reviewed-on: https://gem5-review.googlesource.com/7201
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>
Fold the GDBListener class into the main BaseRemoteGDB class, move
around a bunch of functions, convert a lot of internal functions to
be private, move some functions into the .cc, make some functions
non-virtual which didn't really need to be overridden.
Change-Id: Id0832b730b0fdfb2eababa5067e72c66de1c147d
Reviewed-on: https://gem5-review.googlesource.com/7422
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
Now that Nothing inherits from PageTableBase directly, it can be
merged into FuncPageTable. This change also takes the opportunity to
rename the combined class to EmulationPageTable which lets you know
that it's specifically for SE mode.
Also remove the page table entry cache since it doesn't seem to
actually improve performance. The TLBs likely absorb the majority of
the locality, essentially acting like a cache like they would in real
hardware.
Change-Id: If1bcb91aed08686603bf7bee37298c0eee826e13
Reviewed-on: https://gem5-review.googlesource.com/7342
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>
This patch applies correct miscellaneous or multiply-accumulate op
classes to floating point instructions which had previously been
incorrectly classed as add or multiply instructions.
Change-Id: I959dd8d3152aa341e0f060b003ce1da8c4d688fb
Reviewed-on: https://gem5-review.googlesource.com/6521
Reviewed-by: Alec Roelke <ar4jc@virginia.edu>
Maintainer: Alec Roelke <ar4jc@virginia.edu>
Using the fetestexcept function to check for specific types of floating
point exceptions is unreliable for some kinds of
floating-point-to-integer conversion operations. RISC-V code used to
make use of them to check for some exceptional cases like overflow and
underflow, which caused incorrect output when compiler optimization is
turned on. This patch changes the use of fetestexcept to explicit checks
for those exceptional cases.
Change-Id: Id983906ea0664dc246e115a9e470d9ab7733bde1
Reviewed-on: https://gem5-review.googlesource.com/6402
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Alec Roelke <ar4jc@virginia.edu>
When switching an assert to a fatal while addressing recent review
feedback, I forgot to reverse the polarity of the condition, making
the fatal fire in exactly the opposite of the conditions it was meant
to.
Change-Id: Icf49864ef449052bbb0d427dca786006166575c4
Reviewed-on: https://gem5-review.googlesource.com/7381
Reviewed-by: Matthias Jung <jungma@eit.uni-kl.de>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
This patch fixes a potential crash if an unnamed CSR is accessed and
debug flags are enabled that print disassembly. Unknown CSRs will be
identified as "??" followed by the address that was used.
Change-Id: If5ac57f1422bd59c72a1a06206fa9d9dc05d21ef
Reviewed-on: https://gem5-review.googlesource.com/7321
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Alec Roelke <ar4jc@virginia.edu>
This gets rid of an awkward NoArchPageTable class, and also gives the
arch a place to inject ISA specific parameters (specifically page size)
without having to have TheISA:: in the generic version of these types.
Change-Id: I1412f303460d5c43dafdb9b3cd07af81c908a441
Reviewed-on: https://gem5-review.googlesource.com/6981
Reviewed-by: Alexandru Duțu <alexandru.dutu@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>
This patch makes use of ImmOp's polymorphism to remove unnecessary
casting from the implementations of arithmetic instructions with
immediate operands and to remove the CUIOp format by combining it with
the CIOp format (compressed arithmetic instructions with immediate
operands). Interestingly, RISC-V specifies that instructions with
unsigned immediate operands still need to sign-extend the immediates
from 12 (or 20) bits to 64 bits, so that is left alone.
Change-Id: If20d70c1e90f379b9ed8a4155b2b9222b6defe16
Reviewed-on: https://gem5-review.googlesource.com/6401
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Tuan Ta <qtt2@cornell.edu>
Maintainer: Alec Roelke <ar4jc@virginia.edu>
This constant is, first, a #define, and second only used in one place.
In that one place, it appears that the code it guards is no longer
necessary in general. It was originally written to avoid refetching a
block of data that you're still in, even if you've moved slightly
farther in it because you're skipping the next instruction due to an
annulled branch delay slot. In reality however, in SPARC, the one ISA
I'm aware of which has this sort of branching behavior, the PC state
object will correctly determine that no branch is happening in these
cases. Code lower down in the loop will then recompute where fetching
should continue based on the next PC, automatically skipping the
annulled branch slot without misinterpretting the gap as a branch.
This change therefore also removes this block of code.
Change-Id: I820ebc9df10aeb4fcb69c12f6a784e9ec616743c
Reviewed-on: https://gem5-review.googlesource.com/6821
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Get rid of some remnants of a system which was intended to separate
address computation into its own instruction object.
Change-Id: I23f9ffd70fcb89a8ea5bbb934507fb00da9a0b7f
Reviewed-on: https://gem5-review.googlesource.com/7122
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>
Now that translateFunctional is a virtual function, having an extra
parameter with a default value makes the compiler fall through to the
base implementation instead of overriding it. This change removes the
default value for the extra parameter, and adds a small wrapper with
the correct signature which overrides the base implementation and calls
the full version with the previously default value for the extra
parameter. To callers this will look like the same thing, but the
the right function will get called.
This was what was already being done for transateAtomic and
translateTiming.
Change-Id: I0b71adf34fd6f326005edbb8eaac93275b437c55
Reviewed-on: https://gem5-review.googlesource.com/7121
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>
As per the discussion in patch #6904 and the Linux 4.15 kernel code for
RISC-V, RISC-V has 7 system call argument registers, x10 through x16 (a0
through a6), with x17 (a7) being used for the system call number.
Change-Id: I0080eca78ffa844b322bb2cff2a51ab2815f3809
Reviewed-on: https://gem5-review.googlesource.com/7081
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Tuan Ta <qtt2@cornell.edu>
Maintainer: Alec Roelke <ar4jc@virginia.edu>
getSyscallArg() in RISC-V has an explicit check to make sure that the
register index is within the bounds of the system call register indices
vector. This patch fixes it so that it uses SyscallArgumentRegs.size()
rather than a "magic" constant that has to be updated every time
SyscallArgumentRegs is changed.
Change-Id: I2935d811177dc8028cb3df64b250ba997bc970d8
Reviewed-on: https://gem5-review.googlesource.com/7061
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Alec Roelke <ar4jc@virginia.edu>
That particular ExtMachInst is a convenient placeholder, but a value
of 0 in RISCV or a static uninitialized ExtMachInst (which will
therefore be all zeroes) on x86 works just as well, and removes the
need for an ISA specific constant.
Also, the idea of a universal Nop doesn't always make sense since it
could be that what, exactly, doesn't do anything depends on context
which would be lost on a constant value of an ExtMachInst. For
instance, the value of an ExtMachInst that makes sense might depend on
what mode the CPU was in, etc.
Change-Id: I1f1a43a5c607a667e11b79bcf6e059e4f7141b3f
Reviewed-on: https://gem5-review.googlesource.com/6825
Reviewed-by: Gabe Black <gabeblack@google.com>
Reviewed-by: Alec Roelke <ar4jc@virginia.edu>
Maintainer: Gabe Black <gabeblack@google.com>
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>
This patch is introducing some methods in StaticInst so that is possible
to get the instruction size in byte of the instruction (can be 2 bytes
in Thumb) and the correct opcode (The machInst field contains some
appended metadata)
Change-Id: I3bed4d9fd7c77feaeded40ded192afe445d306ea
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/6781
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
According to the getauxval(3) man page, the AT_RANDOM aux value should
be a pointer to 16 random bytes. In the initial implementation of
RISC-V, this was based on spike's program stack setup, which copied the
program header table there instead. This patch changes the
implementation to use the proper 16 random bytes, making it compatible
with some RISC-V programs that use custom linker scripts.
Change-Id: Idaae7f19bf3ed3fd06d293e5e9c0b6f778270eb2
Reviewed-on: https://gem5-review.googlesource.com/6681
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Alec Roelke <ar4jc@virginia.edu>
This patch increases the maximum stack size of RISC-V, which should help
to reduce problems with programs that allocate large amounts of data on
the stack or do many small allocations.
Change-Id: I1d760050229b12f01a4a8f24c047b587299fef6d
Reviewed-on: https://gem5-review.googlesource.com/6661
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Alec Roelke <ar4jc@virginia.edu>
GCC 7.2 is much stricter than previous GCC versions. The following changes
are needed:
* There is now a warning if there is an implicit fallthrough between two
case statments. C++17 adds the [[fallthrough]]; declaration. However,
to support non C++17 standards (i.e., C++11), we use M5_FALLTHROUGH.
M5_FALLTHROUGH checks for [[fallthrough]] compliant C++17 compiler and
if that doesn't exist, it defaults to nothing (no older compilers
generate warnings).
* The above resulted in a couple of bugs that were found. This is noted
in the review request on gerrit.
* throw() for dynamic exception specification is deprecated
* There were a couple of new uninitialized variable warnings
* Can no longer perform bitwise operations on a bool.
* Must now include <functional> for std::function
* Compiler bug for void* lambda. Changed to auto as work around. See
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82878
Change-Id: I5d4c782a4e133fa4cdb119e35d9aff68c6e2958e
Signed-off-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-on: https://gem5-review.googlesource.com/5802
Reviewed-by: Gabe Black <gabeblack@google.com>
Explicitly separate the way the data is represented in the underlying
representation from how it's represented in the instruction.
In order to make the ISA parser happy, the Mem operand needs to have
a single, particular type. To handle that with scalar types, we just
used uint64_ts and then worked with values that were smaller than the
maximum we could hold. To work with these new array values, we also
use an underlying uint64_t for each element.
To make accessing the underlying memory system more natural, when we
go to actually read or write values, we translate the access into an
array of the actual, correct underlying type. That way we don't have
non-exact asserts which confuse gcc, or weird endianness conversion
which assumes that the data should be flipped 8 bytes at a time.
Because the functions involved are generally inline, the syntactic
niceness should all boil off, and the final implementation in the
binary should be simple and efficient for the given data types.
Change-Id: I14ce7a2fe0dc2cbaf6ad4a0d19f743c45ee78e26
Reviewed-on: https://gem5-review.googlesource.com/6582
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>