The upgraders in util/cpt_upgraders have been able to check the
root.isa element of checkpoints to determine what "the" ISA is for a
simulation, as a quick way to bail out of that particular updater
applies only to specific ISAs. We are moving away from the idea that
there is a single ISA, and so this mechanism will no longer work.
Fortunately, these cpt_upgraders are only relevant for old checkpoints.
If a checkpoint doesn't have a root.isa element inside it at all, we
know (as of this writing) that it is newer than all of these upgraders
and hence they do not apply. Any new upgraders will have to be written
to not rely on the root.isa field which will be removed. If that sort
of field is still needed, it can be added somewhere else in the
hierarchy, perhaps at the system level, or as part of the actual ISA
object.
The simplest way to implement this new behavior is to add a fallback
option when an upgrader looks for root.isa, specifically ''. If the
root.isa element does not exist, the script will get '' back, and this
will not match whatever ISA it's trying to check against. The one even
remotely more complicated script is isa-is-simobject.py which has
several behaviors for different ISAs. In that case, we just explicitly
check for '' and return early if that's what we found.
Jira Issue: https://gem5.atlassian.net/browse/GEM5-1056
Change-Id: Ie78deccb2bac51f38224e62a28dd733cefd63ed7
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/48883
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
With this change serialize.hh is no longer responsible
for the (un)serialization of events. As a general rule,
rules to (un)serialize non-basic types should be defined
at the file that introduces that type. Therefore,
(UN)SERIALIZE_EVENT have been moved to eventq.hh.
Globals has a single instance which must be serialized
and unserialized. Instead of having a stray global
variable handled by Serialization, we pass its management
to Root. As a side effect, Globals is assigned its own
files: sim/globals.(cc/hh).
Finally, 'unserializeGlobals()' is removed, so that
Root can fully handle Globals' serialization. This
breaks checkpoint compatibility, so a checkpoint
upgrader is added.
Change-Id: I9c8e57306f83f9cc30ab2b745a4972755191bec4
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/43586
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
The aforementioned registers (Interrupt Processor Targets Registers) are
banked per-CPU, but are read-only. This patch eliminates the per-CPU
storage of these values that are simply computed.
Change-Id: I52cafc2f58e87dd54239a71326c01f4923544689
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2442
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Weiping Liao <weipingliao@google.com>
The aforementioned upgrader in [1] assumes every option in [system]
has a delimiting '.', and also seems to do its rewriting work a bit too
unconditionally. Most checkpoints in the wild don't have this device,
in which case this script should be a safe no-op.
[1] 2aa4d7b dist, dev: Fixed the packet ordering in etherswitch
Change-Id: Icfd0350985109df1628eb9ab864cda42c54060a8
Reviewed-by: Gabor Dozsa <gabor.dozsa@arm.com>
Updated according to GICv2 documentation.
Change-Id: I5d926d1abf665eecc43ff0f7d6e561e1ee1c390a
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
This patch fixes the order that packets gets pushed into the output fifo
of etherswitch. If two packets arrive at the same tick to the etherswitch,
we sort and push them based on their source port id.
In dist-gem5 simulations, if there is no ordering inforced while two
packets arrive at the same tick, it can lead to non-deterministic simulations
Committed by Jason Lowe-Power <power.jg@gmail.com>
Previous ARM-based simulations were limited to 8 cores due to
limitations in GICv2 and earlier. This changeset adds a set of
gem5-specific extensions that enable support for up to 256 cores.
When the gem5 extensions are enabled, the GIC uses CPU IDs instead of
a CPU bitmask in the GIC's register interface. To OS can enable the
extensions by setting bit 0x200 in ICDICTR.
This changeset is based on previous work by Matt Evans.
Rewrite the HDLCD controller to use the new DMA engine and pixel
pump. This fixes several bugs in the current implementation:
* Broken/missing interrupt support (VSync, underrun, DMA end)
* Fragile resolution changes (changing resolutions used
to cause assertion errors).
* Support for resolutions with a width that isn't divisible by 32.
* The pixel clock can now be set dynamically.
This breaks checkpoint compatibility. Checkpoints can be upgraded with
the checkpoint conversion script. However, upgraded checkpoints won't
contain the state of the current frame. That means that HDLCD
controllers restoring from a converted checkpoint immediately start
drawing a new frame (i.e, expect timing differences).
This commit addresses gem5 checkpoints' linear versioning bottleneck.
Since development is distributed across many private trees, there exists
a sort of 'race' for checkpoint version numbers: internally a checkpoint
version may be used but then resynchronizing with the external tree causes
a conflict on that version. This change replaces the linear version number
with a set of unique strings called tags. Now the only conflicts that can
arise are of tag names, where collisions are much easier to avoid.
The checkpoint upgrader (util/cpt_upgrader.py) upgrades the version
representation, as one would expect. Each tag version implements its
upgrader code in a python file in the util/cpt_upgraders directory
rather than adding a function to the upgrader script itself.
The version tags are stored in the 'Globals' section rather than 'root'
(as the version was previously) because 'Globals' gets unserialized
first and can provide a warning before any other unserialization errors
can occur.
