This commit includes switching to a scrambling RAM primitive for
ICache data and tag RAMs. Also introduces minor changes to ICache
to handle scrambling key valid signal.
It also includes a minor bug fix regarding not initializing
`fill_way_q` signal without ResetAll parameter. When the parameter
is not set and we have our first hit right after ICache enables,
the signal hangs.
Signed-off-by: Canberk Topal <ctopal@lowrisc.org>
This invovles the following changes:
- Rename pcnt to cpop
- Switch encoding of max and minu
- Remove rev from Balanced version, only available in Full version via
grev (Zbp)
- Include sext.b/h (previously in Zb_tmp)
- Remove slo[i] and sro[i] from Balanced version, only available in Full
version (Zbp)
Signed-off-by: Pirmin Vogel <vogelpi@lowrisc.org>
This change is related to the bitmanip draft version 0.94. It's needed
as in draft version 0.93 as well as in version 1.00 sbext from Zbs
changes to bext, leading to two completely different instructions having
the same name.
Signed-off-by: Pirmin Vogel <vogelpi@lowrisc.org>
This matches the priority used in Spike.
This also fixes an issue in the DV where the priority of
external/software/timer interrupts wasn't calculated correctly.
Extra bits are added alongside read/write data for the instruction and
data buses to facilitate data integrity checking.
Ibex testbench extended to generate the expected bits.
All other top-levels modified to add the new signals (which are mostly
ignored).
Signed-off-by: Tom Roberts <tomroberts@lowrisc.org>
Random constants are sent through the hierarchy as parameters in-line
with other OpenTitan modules.
Further detail on this mechanism can be found in lowrisc/opentitan#2229
Signed-off-by: Tom Roberts <tomroberts@lowrisc.org>
mseccfg and mseccfgh have changed their addresses. This updates to the
newly allocated values.
The ePMP specification is now available as a versioned PDF,
documentation is updated to point to that removing the local PDF copy.
This signal used to be a one shot enable out of reset. We need an option
to pause execution for OpenTitan, so fetch_enable is extended to cover
that.
The signal is already driven low by the testbench at the end of test.
This is moved after the performance counter reads to ensure they can
complete.
Fixes#1105
Signed-off-by: Tom Roberts <tomroberts@lowrisc.org>
Note that the alert output is tied off for now until an option is added
to reset all registers (otherwise there will be X propagation).
Signed-off-by: Tom Roberts <tomroberts@lowrisc.org>
This commit creates a new top level wrapping the core, register file and
icache RAMs. The tracing top level is also renamed to ibex_top_tracing
to match. This new top level is intended to enable a dual core lockstep
implementation of Ibex.
There are no functional changes in this commit, only wiring.
Signed-off-by: Tom Roberts <tomroberts@lowrisc.org>
We were using the old html_context which has been deprecated
for a while. This PR switches to html_css_files instead.
See sphinx-doc/sphinx#8885 for more information.
This should match what's going on a bit more accurately. The link to
OVPsim now points at the (free of cost) commercial tool: riscv-ovpsim
doesn't support the bitmanip specification that we're using at the
moment.
Remove the SpeculativeRequest parameter, and replace it with a
policy. If the cache is disabled, make the request on the basis that we
definitely won't hit in the cache and so should make the bus request
asap.
Stop fill buffers from fetching complete cache lines when the cache is
disabled. When the core branches into the middle of a line, the lower
words would normally be fetched to complete the line. This is
unnecessary when the cache is disabled since those words will just be
thrown away and the core will stall while they are being fetched.
These two changes make the performance using the disabled icache the
same as using non-icache prefetch buffer.
Signed-off-by: Tom Roberts <tomroberts@lowrisc.org>
This commit amends some paths in the vendoring hjson file (and updates
config files to use things at the new paths). Finally it re-runs the
vendoring tool:
Update code from upstream repository
https://github.com/lowRISC/opentitan to revision
92e9242424c72c59008e267dd3779e2af5ec8e83
which just ends up with a load of file renames.
Signed-off-by: Rupert Swarbrick <rswarbrick@lowrisc.org>
A few tweaks to fix broken links, make explanations more clear and
update the information to reflect the present (e.g. Spike master now
implements bit-manip, the seperate branch is gone).
Add parameter `DbgHwBreakNum` to configure the number of HW breakpoints.
The parameters controls the number of trigger registers available if
debug support is enabled with `DbgTriggerEn`.
Closes#1070
- Document that SecureIbex cannot be used without a multiplier and add
an assertion in the rtl. This fixes#1080.
- Move the PC checking hardware onto its own parameter to match all the
other individual security features.
- Make the PC increment behavior more sensible on fetch errors (and make
it match the icache behavior). Factor this into the PC increment check
to prevent false triggering, fixes#1094.
- Stop the PC mismatch checker firing on dummy instructions, fixes
#1095.
Signed-off-by: Tom Roberts <tomroberts@lowrisc.org>
Option to control the state of the Ibex tracer.
Defaults to enable, but allows a setting to disable the trace log.
In long running simulations this file can get quite big and the contents
might not be needed. Use the argument `+ibex_tracer_enable=0` to prevent
the creation of the file.
Restructure the existing documentation to group the content by intended
audience. This produces four sections:
* An introduction section, relevant to "newcomers" to Ibex.
* An user guide, intended for hardware designers (integrators) and
software developers who want to integrate Ibex, and develop software
for it.
* A reference guide, which provides background information on the
design. This section is essential when working on Ibex, and also
documents our design decisions.
* A developer guide aimed at people modifying Ibex itself. It consists
mostly of process and tool documentation: how to run the verification
after a code change, how to use GitHub, etc.
This commit is large, but text is mostly unchanged. A couple of
introductions and tables of content were added, but no significant
changes to the text have been made. These will be done in follow-ups.
Signed-off-by: Philipp Wagner <phw@lowrisc.org>
