In python, the BARs had been configured using three arrays and a scalar
parameter. The arrays tracked the BAR value in the config, whether the
BAR was for a "legacy" IO range, and the size of the BAR, and the
scalar parameter was an offset for the "legacy" IO addresses to map
into the host physical address space. The nature of a BAR was implied
by its raw config space value, with each of the control bits (IO vs.
memory, 64 bit, reserved bits) encoded directly in the value.
Now, the BARs are represented by objects which have different types
depending on what type of BAR they are. There's one for IO, one for
memory, one for the upper 32 bits of a 64 bit BAR (so indices work
out), and one for legacy IO ranges. Each type has parameters which
are appropriate for it, and they're parameters are all grouped together
as a unit instead of being spread across all the previous values.
The legacy IO offset has been removed, since these addresses can be
offset like any other IO address. They can be represented naturally
in the config using their typical IO port numbers, and still be turned
into an address that gem5 will handle correctly in the back end.
Unfortunately, this exposes a problem in the config system where
a VectorParam can't be overwritten successfully one element at a time,
at least when dealing with SimObject classes. It might work with
actual SimObjects in a config, but I haven't tried it. If you were
to do that to, for instance, update the BARs for x86 so that they
used legacy IO ports for the IDE controller, it would complain that
you were trying to instantiate orphaned nodes. Replacing the whole
VectorParam with a new list of BAR objects seems to work, so that's
what's implemented in this change.
On the C++ side, BARs in the config space are treated as flat values
on reads, and are stored in the config structure associated with each
PCI device. On writes, the value is first passed to the BAR object,
and it has a chance to mask any bits which are fixed in hardware and
update its idea of what range it corresponds to in memory.
When sending AddrRanges up to the parent bus to set up routing, the
BARs generate each AddrRange if and only if their type has been
enabled in the config space command register. The BAR object which
represents the upper 32 bits of a 64 bit BAR does not claim to be
IO or memory, and so doesn't contribute a range. It communicates with
the BAR which represents the lower 32 bits, so that that BAR has the
whole base address.
Since the IO or memory BAR enable bits in the command register are now
handled by the PCI device base class, the IDE controller no longer has
to handle that manually. It does still need to keep track of whether
the bus master functionality has been enabled though, which it can
check when those registers are accessed.
There was already a mechanism for decoding addresses based on BARs
in the PCI device base class, but it was overly complicated and not
used consistently across devices. It's been consolidated, and used in
most places where it makes sense.
Finally, a few unnecessary values have been dropped from the base PCI
device's and IDE controller's checkpoint output. These were just local
copies of information already in the BARs, which in turn are already
stored along with the data in the device's config space.
Change-Id: I16d5f8cdf86d7a2d02a6b04d1f9e1b3eb1dd189d
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/35516
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The create() method on Params structs usually instantiate SimObjects
using a constructor which takes the Params struct as a parameter
somehow. There has been a lot of needless variation in how that was
done, making it annoying to pass Params down to base classes. Some of
the different forms were:
const Params &
Params &
Params *
const Params *
Params const*
This change goes through and fixes up every constructor and every
create() method to use the const Params & form. We use a reference
because the Params struct should never be null. We use const because
neither the create method nor the consuming object should modify the
record of the parameters as they came in from the config. That would
make consuming them not idempotent, and make it impossible to tell what
the actual simulation configuration was since it would change from any
user visible form (config script, config.ini, dot pdf output).
Change-Id: I77453cba52fdcfd5f4eec92dfb0bddb5a9945f31
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/35938
Reviewed-by: Gabe Black <gabeblack@google.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This change replaces the __attribute__ syntax with the now standard [[]]
syntax. It also reorganizes compiler.hh so that all special macros have
some explanatory text saying what they do, and each attribute which has a
standard version can use that if available and what version of c++ it's
standard in is put in a comment.
Also, the requirements as far as where you put [[]] style attributes are
a little more strict than the old school __attribute__ style. The use of
the attribute macros was updated to fit these new, more strict
requirements.
Change-Id: Iace44306a534111f1c38b9856dc9e88cd9b49d2a
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/35219
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The code in this #ifdef isn't turned on by anything, and either has or
likely will bitrot, especially since there are no tests to even
determine manually if the code they guard works. They are also
preceeded by panics which say that the code they guard is known not to
work now anyway.
This change also gets rid of TheISA in that file since the only reason
it was around was for vtophys in the guarded code.
Change-Id: I59fd8974d0dd3d7ab0d5a8ccfa6a446d2da41eb0
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/22265
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Generally speaking, the endianness of the data devices provide or
accept is dependent on the device and not the ISA the system
executes. This change makes the devices in dev pick an endianness
rather than using the guest's.
For the ISA bus and the UART, accesses are byte sized and so endianness
doesn't matter. The ISA and PCI busses and the devices which use them
are defined to be little endian.
Change-Id: Ib0aa70f192e1d6f3b886d9f3ad41ae03bddb583f
Reviewed-on: https://gem5-review.googlesource.com/c/13462
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Changeset 11701 only serialized the useful portion of of an ethernet packets'
payload. However, the device models expect each ethernet packet to contain
a 16KB buffer, even if there is no data in it. This patch adds a 'bufLength'
field to EthPacketData so the original size of the packet buffer can always
be unserialized.
Reported-by: Gabor Dozsa <Gabor.Dozsa@arm.com>
Currently, all the network devices create a 16K buffer for the 'data' field
in EthPacketData, and use 'length' to keep track of the size of the packet
in the buffer. This patch introduces the 'simLength' parameter to
EthPacketData, which is used to hold the effective length of the packet used
for all timing calulations in the simulator. Serialization is performed using
only the useful data in the packet ('length') and not necessarily the entire
original buffer.
By ignoring SIG_TRAP, using --debug-break <N> when not connected to
a debugger becomes a no-op. Apparently this was intended to be a
feature, though the rationale is not clear.
If we don't ignore SIG_TRAP, then using --debug-break <N> when not
connected to a debugger causes the simulation process to terminate
at tick N. This is occasionally useful, e.g., if you just want to
collect a trace for a specific window of execution then you can combine
this with --debug-start to do exactly that.
In addition to not ignoring the signal, this patch also updates
the --debug-break help message and deletes a handful of unprotected
calls to Debug::breakpoint() that relied on the prior behavior.
