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>
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>
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>
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>
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>
Paul Mackerras
Benjamin Herrenschmidt