This patch fixes two problems with the O3 cpu model. The first is an issue
with an instruction fetch causing a fault on the next address while the
current macro-op is being issued. This happens when the micro-ops exceed
the fetch bandwdith and then on the next cycle the fetch stage attempts
to issue a request to the next line while it still has micro-ops to issue
if the next line faults a fault is attached to a micro-op in the currently
executing macro-op rather than a "nop" from the next instruction block.
This leads to an instruction incorrectly faulting when on fetch when
it had no reason to fault.
A similar problem occurs with interrupts. When an interrupt occurs the
fetch stage nominally stops issuing instructions immediately. This is incorrect
in the case of a macro-op as the current location might not be interruptable.
The virtual channels within "response" vnets are made buffers_per_data_vc
deep (default=4), while virtual channels within other vnets are made
buffers_per_ctrl_vc deep (default = 1). This is for accurate power estimates.
A recent patch broke the ruby network tester by adding -p inside Options.py
which conflicts with the -p inside ruby_network_test.py.
Have removed -p from ruby_network_test.py
Identifying response vnets versus other vnets will allow garnet to
determine which vnets will carry data packets, and which will carry
ctrl packets, and use appropriate buffer sizes (since data packets are larger
than ctrl packets). This in turn allows the orion power model to accurately
estimate buffer power.
Renamed (message) class to vnet for consistency with rest of ruby.
Moved some parameters specific to fixed/flexible garnet networks into their
corresponding py files.
This change further eliminates cases where condition codes were being read
just so they could be written without change because the instruction in
question was supposed to preserve them. This is done by creating the condition
code code based on the input rather than just doing a simple substitution.
If one of the condition codes isn't being used in the execution we should only
read it if the instruction might be dependent on it. With the preeceding changes
there are several more cases where we should dynamically pick instead of assuming
as we did before.
Break up the condition code bits into NZ, C, V registers. These are individually
written and this removes some incorrect dependencies between instructions.
Move the saturating bit (which is also saturating) from the renamed register
that holds the flags to the CPSR miscreg and adds a allows setting it in a
similar way to the FP saturating registers. This removes a dependency in
instructions that don't write, but need to preserve the Q bit.
This change splits out the condcodes from being one monolithic register
into three blocks that are updated independently. This allows CPUs
to not have to do RMW operations on the flags registers for instructions
that don't write all flags.
Debug flags are ExecUser, ExecKernel, and ExecAsid. ExecUser and
ExecKernel are set by default when Exec is specified. Use minus
sign with ExecUser or ExecKernel to remove user or kernel tracing
respectively.
Add registers and components to better support the VersatileEB board.
Made the MIDR and SYS_ID register parameters to ArmSystem and RealviewCtrl
respectively.
Instructions that load an address and are control instructions can
execute down the wrong path if they were predicted correctly and then
instructions following them are squashed. If an instruction is a
memory and control op use the predicted address for the next PC instead
of just advancing the PC. Without this change NPC is used for the next
instruction, but predPC is used to verify that the branch was successful
so the wrong path is silently executed.
The network tester terminates after injecting for sim_cycles
(default=1000), instead of having to explicitly pass --maxticks from the
command line as before. If fixed_pkts is enabled, the tester only
injects maxpackets number of packets, else it keeps injecting till sim_cycles.
The tester also works with zero command line arguments now.
The RubyMemory flag wasnt used in the code, creating large gaps in trace output. Replace cprintfs w/dprintfs
using RubyMemory in memory controller. DPRINTF also deprecate the usage of the setDebug() pure virtual
function in the AbstractMemoryOrCache Class as well the m_debug/cprintf functions in MemoryControl.hh/cc
Make sure all command-line targets and EXTRAS directories
are interpreted relative to the launch directory. This
turns out to be very useful when building code from an
EXTRAS directory using SCons's -C option.
We were trying to do this with targets but it didn't actually
work since we didn't update BUILD_TARGETS (so SCons got
confused internally). We weren't even trying with EXTRAS.
To simplify the code, the default target is also interpreted
relative to the launch dir even though it was explicitly
handled as relative to the m5 dir before... I doubt anyone
really uses this anyway so it didn't seem worth the complexity.
(Maybe we should get rid of it?)
Currently the --default= option only looks at the predefined
build configs (in m5/build_opts), so you're limited to basing
a new build config off of those (ALPHA_SE, etc.). If you've
already defined a non-standard build config and want to clone
it or tweak it, you have to start from scratch. This patch
causes --default= to look first among the existing builds
(in build/variables) before looking in build_opts so you
can specify an existing non-standard build config as a
starting point for a new config.
This change replaces the mkblankimage.sh script, used for creating new disk
images, with a new gem5img.py script. The new version is written in python
instead of bash, takes its parameters from command line arguments instead of
prompting for them, and finds a free loopback device dynamically instead of
hardcoding /dev/loop1. The file system used is now optionally configurable,
and the blank image is filled by a "hole" left by lseek and write instead of
literally filling it with zeroes.
The functionality of the new script is broken into subcommands "init",
"mount", "umount", "new", "partition", and "format". "init" creates a new file
of the appropriate size, partitions it, and then formats the first (and only)
new parition. "mount" attaches a new loopback device to the first parition of
the image file and mounts it to the specified mount point. "umount" unmounts
the specified mount point and identifies and cleans up the underlying loopback
device. "new", "partition", and "format" are the individual stages of "init"
but broken out so they can be run individually. That's so an image can be
reinitialized in place if needed.
Two features of the original script are being dropped. The first is the
ability to specify a source directory to copy into the new file system. The
second is the ability to specify a list of commands to run which are expected
to (but not required to) update the permissions of the files in the new fs.
Both of these seem easy enough to do manually, especially given the "mount"
and "umount" commands, that removing them would meaningfully simplify the
script without making it less useful.
