Hi everyone,
A while back I sent in a patch that adds support for watchpoint lengths greater
than four on xscale. It's been working well, until the other day, when it
caused an unexpected debug exception. Looking into this I realized there is a
case where it breaks: when the length arg is greater than the base address.
This is a consequence of the way the hardware works. Don't see a work-around,
so I added code to xscale_add_watchpoint() to check for and disallow this
combination.
Some more detail... xscale watchpoint hardware does not support a length
directly. Instead, a mask value can be specified (not to be confused with the
optional mask arg to the wp command, which xscale does not support). Any bits
set in the mask are ignored when the watchpoint hardware compares the access
address to the watchpoint address. So as long as the length is a power of two,
setting the mask to length-1 effectively specifies the length. Or so I thought,
until I realized that if the length exceeds the base address, *all* bits of the
base address are ignored by the comaparator, and the watchpoint range
effectively becomes 0 .. length.
Questions, comments, criticisms gratefully received.
Thanks,
Mike
Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Hi everyone,
Added more LOG_ERROR messsages to watchpoint and breakpoint code, given that the
infrastructure no longer interprets returned error codes. Also changed
existing LOG_INFO and LOG_WARNING to LOG_ERROR for cases where an error is
returned.
Note that the check of the target state is superflous, since the infrastruture
code currently checks this before calling target code. Is this being
reconsidered as well? Also, should we stop returning anything other than
ERROR_OK and ERROR_FAIL?
Comments gratefully received.
Thanks,
Mike
Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
do not try to interpret "retval" into a string, just
amend a bit about the context of the already reported
error.
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
Hi everyone,
Version 2 of this patch. Code added to breakpoints.c was removed from previous
patch, and item 3 added, per discussion with Øyvind regarding error reporting.
Item 4 added, which I just noticed.
I tried to use a software breakpoint in thumb code on the xscale for the first
time recently, and was surprised to find that it didn't work. The result was
this patch, which does four things:
1): fix trivial cut-n-paste error that caused thumb breakpoints to not work
2): call xscale_set_breakpoint() from xscale_add_breakpoint()
3): log error on data abort in xscale_write_memory()
4): fixed incorrect error code returned by xscale_set_breakpoint() when no
breakpoint register is available; added comment
Item 2 not only makes the xscale breakpoint code consistent with other targets,
but also alerts the user immediately if an error occurs when writing the
breakpoint instruction to target memory (previously, xscale_set_breakpoint() was
not called until execution resumed). Also, calling xscale_breakpoint_set() as
part of the call chain starting with handle_bp_command() and propagating the
return status back up the chain avoids the situation where OpenOCD "thinks" the
breakpoint is set when in reality an error ocurred.
Item 3 provides a helpful message for a common reason for failure to set sw
breakpoint.
This was thoroughly tested, mindful of the fact that breakpoint management is
somewhat dicey during single-stepping.
Comments and criticisms of course gratefully received.
Mike
Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
Hi everyone,
I figured since I was poking around in the breakpoint code on other arches, I'd
add this change to those arches that don't do it already. This patch propagates
the return code of <arch>_set_breakpoint() up the call stack. This ensures that
the higher layer breakpoint infrastructure is aware that an error ocurred, in
which case the breakpoint is not recorded.
Normally I wouldn't touch code that I can't test, but the code is very
uniform across architectures, and the change is rather benign, so I figured
after careful inspection that it is safe. If the maintainers or others think
this is imprudent, the patch can be dropped.
Also changed the error code to something more appropriate in two cases where
hardware resources are unavailable.
Comments and criticisms of course gratefully received.
Mike
Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
Hi everyone,
This simple patch fixes a problem I noticed on the xscale where incorrect values
are sometimes reported by the reg command. The problem can occur when
requesting the value of registers in the xscale-specific register cache. With a
couple of exceptions, none of the registers in the xscale register cache are
automatically retrieved on debug entry. This is probably fine, as they are
unlikely to be needed on a regular basis during a typical debug session, and
they can be retrieved when explicitly requested by name using the reg command.
The problem is that once this is done, the register remains marked as valid for
the remainder of the OpenOCD session, and the reg command will henceforth always
report the same value because it is obtained from the cache and is never again
retrieved from the debug handler on the target.
The fix is to mark all registers in the xscale register cache as invalid on
debug entry (before the two exceptions are retrieved), thus forcing retrieval
(when requested) from the target across resumptions in execution, and avoiding
the reporting of stale values.
Small addition change by Øyvind: change 'i' to unsigned to fix compiler
warning for xscale_debug_entry() fn.
Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
This new cmd adds the ability to choose the Cortex-M3
reset method used.
It defaults to using SRST for reset if available otherwise
it falls back to using NVIC VECTRESET. This is known to work
on all cores.
Move any luminary specific reset handling to the stellaris cfg file.
Signed-off-by: Spencer Oliver <ntfreak@users.sourceforge.net>
committed so as to ease cooperation and to let it be improved
over time.
So far it supports:
- halt/resume
- registers inspection
- memory inspection/modification
I'm still getting up to speed with OpenOCD internals and AVR32 so code is a little
bit messy and I'd appreciate any feedback.
ocd_ prefix is used internally in OpenOCD as a kludge more
or less to deal with the two kinds of commands that OpenOCD
has.
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
if polling is off, then "reset run + halt" would fail
since halt incorrectly assumed the target was in the
reset state as it is the internal poll implementation
that moves the sw tracking of the target state out
of the reset state.
To reproduce:
> reset run; halt
JTAG tap: zy1000.cpu tap/device found: 0x1f0f0f0f (mfg: 0x787, part: 0xf0f0, ver: 0x1)
BUG: arm7/9 does not support halt during reset. This is handled in arm7_9_assert_reset()
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
back-off algorithm for polling. Double polling
interval up to 5000ms when it fails.
when polling succeeds, reset backoff.
This avoids flooding logs(as much) when working
with conditions where the target polling will fail.
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
It is useful to know that the printed errors are *all* the
errors there were.
Added missing error handling(found by inspection).
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
As the mips32 uses instruction breakpoints for algorithms we do not really
need to check the pc on exit.
This now matches the behaviour of the arm codebase.
Signed-off-by: Spencer Oliver <ntfreak@users.sourceforge.net>
As the armv7m uses instruction breakpoints for algorithms we do not really
need to check the pc on exit.
This now matches the behaviour of the arm4_5 codebase.
Signed-off-by: Spencer Oliver <ntfreak@users.sourceforge.net>
Update the arm_checksum_memory and arm_blank_check_memory
algorithms to use a breakpoint instruction on v5 arch.
Signed-off-by: Spencer Oliver <ntfreak@users.sourceforge.net>
Use addition for offsetting, not masking. Shorten some lines.
Make "component_start" print-only (unused otherwise; don't save).
Still doesn't resolve the issue where multiple components
are wrongly displaying as NVICs on some Cortex-M3 parts because
many PIDs appear to be zeroes ... maybe adapter related??
Signed-off-by: David Brownell <db@helium.(none)>
Mask the upper bits after 32-bit reads.
Alsoo revert the ugly changes to use PRIx32; just cast to unsized
integers when printing (two chars not eight).
Signed-off-by: David Brownell <db@helium.(none)>
This reverts the incorrect change made to the arm9 cmd group in commit
d1eca9a74c.
The code now matches the docs and the release notes.
Signed-off-by: Spencer Oliver <ntfreak@users.sourceforge.net>
The code did not transfer the last word in no-ack transfers.
The strange thing is that this did not lead to any
observable errors.
This gaffe was introduced in commit 1f5883ea56
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
Review allocation of error numbers in openocd
to avoid overlap.
Put brackets around negative numbers to avoid
issues during macro expansion.
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Memory read/writes to virtual memory, requires that the CPU is
halted.
Use 'phys' option to write to memory while target is running.
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
when locking the debug access fails on the first try, it's a
bit noisy, so print out message that it succeeded on second try.
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
