Commit Graph

26 Commits (master)

Author SHA1 Message Date
Paul Mackerras 4bef477e29 core_debug: Add support for detecting writes to a memory address
This adds a new type of stop trigger for the log buffer which triggers
when any byte(s) of a specified doubleword of memory are written.
The trigger logic snoops the wishbone for writes to the address
specified and stops the log 256 cycles later (same as for the
instruction fetch address trigger).  The trigger address is a real
address and sees DMA writes from devices as well as stores done by the
CPU.

The mw_debug command has a new 'mtrig' subcommand to set the trigger
and query its state.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
8 months ago
Paul Mackerras af814a0d5e Provide debug access to SPRs in loadstore1 and mmu
They are accessible as GSPR 0x3c - PID, 0x3d - PTCR, 0x3e - DSISR
and 0x3f - DAR.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2 years ago
Paul Mackerras d0f319290f Restore debug access to SPRs
This provides access to the SPRs via the JTAG DMI interface.  For now
they are still accessed as if they were GPR/FPRs using the same
numbering as before (GPRs at 0 - 0x1f, SPRs at 0x20 - 0x2d, FPRs at
0x40 - 0x5f).

For XER, debug reads now report the full value, not just the bits that
were previously stored in the register file.  The "slow" SPR mux is
not used for debug reads.

Decode2 determines on each cycle whether a debug SPR access will
happen next cycle, based on whether there is a request and whether the
current instruction accesses the SPR RAM.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2 years ago
Matt Johnston c0c00d05bc mw_debug: Add STATIC_URJTAG flag
Revert to linking dynamically by default, can statically link with
`make STATIC_URJTAG=1`

Fixes #351

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
2 years ago
Matt Johnston 9c64f8a98b mw_debug: Add Lattice ECP5 support
"-b ecp5" will select ECP5 interface that talks to a JTAGG
primitive.

For example with a FT232H JTAG board:

./mw_debug  -t 'ft2232 vid=0x0403 pid=0x6014'  -s 30000000 -b ecp5 mr ff003888 6
Connected to libftdi driver.
Found device ID: 0x41113043
00000000ff003888: 6d6f636c65570a0a  ..Welcom
00000000ff003890: 63694d206f742065  e to Mic
00000000ff003898: 2120747461776f72  rowatt !
00000000ff0038a0: 0000000000000a0a  ........
00000000ff0038a8: 67697320636f5320   Soc sig
00000000ff0038b0: 203a65727574616e  nature:
Core: running
 NIA: c0000000000187f8
 MSR: 9000000000001033

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
2 years ago
Matt Johnston eb20195a10 mw_debug: Link urjtag statically
liburjtag isn't in Debian, so usually we're pointing at a urjtag
build directory when building mw_debug

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
2 years ago
Matt Johnston 763138798e mw_debug: use isxdigit for hex arguments
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
2 years ago
Matt Johnston 04cc4a842c mw_debug: Add -s frequency argument
Chose -s for speed, vs -f for --force

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
2 years ago
Matt Johnston e05ae0c8cb mw_debug: pass target parameters to urjtag
An example

./mw_debug -d -t 'ft2232 vid=0x0403 pid=0x6014'

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
2 years ago
Benjamin Herrenschmidt b557ec3a05 mw_debug: Default to jtag backend if unspecified
It avoids typing it all the time

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
3 years ago
Benjamin Herrenschmidt 4bdfef9a20 mw_debug: Probe cable if unspecified
Instead of defaulting to DigilentHS1

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
3 years ago
Paul Mackerras 470f1b2140 core_debug: Add an address trigger to stop logging at a given address
This compares the address being fetched with the contents of a
register that can be set via DMI, and if they match, stops the
logging.  Since this works on the address being fetched rather than
executed, it is subject to false positives.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
3 years ago
Paul Mackerras f14e731ec6 mw_debug: Display terminated status when stopping
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
3 years ago
Paul Mackerras 6baf3b519f mw_debug: Extend to handle FPRs
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
3 years ago
Paul Mackerras 49a4d9f67a Add core logging
This logs 256 bits of data per cycle to a ring buffer in BRAM.  The
data collected can be read out through 2 new SPRs or through the
debug interface.

The new SPRs are LOG_ADDR (724) and LOG_DATA (725).  LOG_ADDR contains
the buffer write pointer in the upper 32 bits (in units of entries,
i.e. 32 bytes) and the read pointer in the lower 32 bits (in units of
doublewords, i.e. 8 bytes).  Reading LOG_DATA gives the doubleword
from the buffer at the read pointer and increments the read pointer.
Setting bit 31 of LOG_ADDR inhibits the trace log system from writing
to the log buffer, so the contents are stable and can be read.

There are two new debug addresses which function similarly to the
LOG_ADDR and LOG_DATA SPRs.  The log is frozen while either or both of
the LOG_ADDR SPR bit 31 or the debug LOG_ADDR register bit 31 are set.

The buffer defaults to 2048 entries, i.e. 64kB.  The size is set by
the LOG_LENGTH generic on the core_debug module.  Software can
determine the length of the buffer because the length is ORed into the
buffer write pointer in the upper 32 bits of LOG_ADDR.  Hence the
length of the buffer can be calculated as 1 << (31 - clz(LOG_ADDR)).

There is a program to format the log entries in a somewhat readable
fashion in scripts/fmt_log/fmt_log.c.  The log_entry struct in that
file describes the layout of the bits in the log entries.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
4 years ago
Paul Mackerras aab84acda8 scripts/mw_debug: Make progress counts display on one line
This outputs a carriage return rather than a newline after the
display of the progress count during the load and save operations.
This makes the output more compact and better looking.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
4 years ago
Benjamin Herrenschmidt 3c99e6c31f mw_debug: Add "save" function to save memory to a file
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
4 years ago
Benjamin Herrenschmidt b8df0647fd mw_debug: Fix memory overflow with "sim" backend
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
4 years ago
Joel Stanley 5860c2d1b6 mw_debug: Add README
This describes how to build the tool on Fedora, and on Debian which lacks a packaged
liburjtag as of mid 2020.

Signed-off-by: Joel Stanley <joel@jms.id.au>
4 years ago
Joel Stanley 2bf5bf4bac mw_debug: Add usage text
Signed-off-by: Joel Stanley <joel@jms.id.au>
4 years ago
Joel Stanley fa90f0dbb1 mw_debug: Add CFLAGS and fix warnings
CFLAGS was defined but not used anywhere. This adds them to the compile
line, and fixes the warnings (and errors!) that result.

Signed-off-by: Joel Stanley <joel@jms.id.au>
4 years ago
Paul Mackerras c164a2f4ea Merge branch 'mmu'
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
4 years ago
Paul Mackerras 3340d8aa9f mw_debug: Add support for reading GSPRs and writing memory
This adds a "gpr" command for reading 1 or more GPRs/fast SPRs,
and a "mw" command for writing an 8-byte value to memory.  It also
adds an "icreset" command for resetting the instruction cache
and fixes the "creset" command to actually reset the core instead
of starting it.  The MSR is now printed along with the NIA in the
status information.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
4 years ago
Benjamin Herrenschmidt 982cf166dd litedram: Add basic support for LiteX LiteDRAM
This comes in two parts:

 - A generator script which uses LiteX to generate litedram cores
along with their init files for various boards (currently Arty and
Nexys-video). This comes with configs for arty and nexys_video.

 - A fusesoc "generator" which uses pre-generated litedram cores

The generation process is manual on purpose. This include pre-generated
cores for the two above boards.

This is done so that one doesn't have to install LiteX to build
microwatt. In addition, the generator script or wrapper vhdl tend to
break when LiteX changes significantly which happens.

This is still rather standalone and hasn't been plumbed into the SoC
or the FPGA toplevel files yet.

At this point LiteDRAM self-initializes using a built-in VexRiscv
"Minimum" core obtained from LiteX and included in this commit. There
is some plumbing to generate and cores that are initialized by Microwatt
directly but this isn't working yet and so isn't enabled yet.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
4 years ago
Benjamin Herrenschmidt fa50df56ef mw_debug: Fix core reset
mw_debug creset would poke the START bit instead of the RESET bit

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
4 years ago
Benjamin Herrenschmidt fe275effeb New C based JTAG debug tool
This works with both the sim socket and urjtag, and supports the
new core functions, loading a file in memory etc...

The code still needs a lot of cleanup and a help!

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
5 years ago