Commit Graph

11 Commits (9208276aa276c3e48af6ff758dc4e450d5e775ac)

Author SHA1 Message Date
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>
4 years ago
Paul Mackerras f14e731ec6 mw_debug: Display terminated status when stopping
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
4 years ago
Paul Mackerras 6baf3b519f mw_debug: Extend to handle FPRs
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
4 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>
5 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>
5 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>
5 years ago
Benjamin Herrenschmidt b8df0647fd mw_debug: Fix memory overflow with "sim" backend
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
5 years ago
Joel Stanley 2bf5bf4bac mw_debug: Add usage text
Signed-off-by: Joel Stanley <joel@jms.id.au>
5 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>
5 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>
5 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