No point in both ARM11 and Cortex-A8 having private copies
of the logic sorting out e.g. DBG_REASON_WATCHPOINT.
Add and use a shared routine for this ... there's actually
a bunch more debug entry logic that could be shared, this
is just a start on that. Note that this routine fixes a
bug observed in the ARM11 code, where some abort mode quirks
were displayed as being an unknown debug reason; and also
silences needless ARM11 chatter.
Likewise with private copies of DSCR ... add one to the DPM
struct. Save it as part of setting DBG_REASON_* so later
patches can switch over to using that copy.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Move the symbols for these bits from "armv7a.h" to "arm_dpm.h",
where they can be seen and used not just by Cortex-A but also
by the ARM11 (armv6) code.
Change them from bit numbers to bit masks ... this matches the
usage in ARM11 code, and also makes it easier to read.
Rename DSCR_EXT_INT_EN as DSCR_ITR_EN to match the docs; it's
enabling ITR functionality, not external interrupts, so this
changes the name to be less misleading. (There *IS* a bit
affecting interrupts, and this isn't it.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Save and display the address of the instruction which triggered the
watchpoint. Because of pipelining, that's well behind the PC value
when debug entry completes. (Example in a subroutine that had been
returned from...)
Remove unused A8 stuff, mostly watchpoint hooks from the header.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Actually this should handle both breakpoints and watchpoints ... but
the DPM framework only handles watchpoints for now. Works on Beagle.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
This is a NOP unless the underlying core exposes two new methods, and
neither of the two cores using this (ARM11xx, Cortex-A8) do so yet.
This patch only updates those cores so they pass a flag saying whether
or not to update breakpoint and watchpoint status before resuming; and
removing some now-needless anti-segfault code from ARM11. Cortex-A8
didn't have that code ... yes, it segfaulted when setting watchpoints.
NOTE: this uses a slightly different strategy for setting/clearing
breakpoints than the ARM7/ARM9/etc code uses. It leaves them alone
unless it's *got* to change something, to speed halt/resume cycles
(including single stepping).
ALSO NOTE: this under-delivers for Cortex-A8, where regions with size
up to 2 GBytes can be watched ... it handles watchpoints which ARM11 can
also handle (size 1/2/4 bytes). Should get fixed later.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
We don't need this code, now that the DPM code handles it.
Neither do we need the ARMv7-A CP15 operations; remove their
remnants too. And disable a mostly-needless diagnostic.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Switch "mrc" and "mcr" commands to be toplevel ARM operations,
as they should initially have been.
Correct the usage message for both commands: it matches ARM
documentation (as one wants!) instead of reordering them to
match the funky mrc() and mcr() method usage (sigh).
For Cortex-A8: restore a line that got accidentally dropped,
so the secure monitor mode shadow registers will show again.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
There were two chunks of Cortex-A8 code which called the
ARMv7-A CP15 operations; get rid of them, helping prepare
to remove those methods completely:
- post_debug_entry() can use the mrc() method to read
its two registers.
- write_memory() can use dpm->instr_write_data_r0() to
flush the ICache and DCache ... doing it this way is
actually faster since it reduces per-write overhead.
Note that the mrc() method parameters are re-ordered with
respect to the ARM instruction documentation, so that part
can be confusing.
Cleaned up the layout and comments in those areas a bit.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Use the new "reset-assert" event; else SRST; else fail.
Tested on an OMAP3, using the event.
NOTE: still doesn't handle "reset halt". For some reason
neither VCR nor PRCR seemed effective; they held the value
that was written, but VCR didn't trigger debug entry when
the reset vector fired (maybe the vector needs configuring?)
and PRCR refused to hold the chip in reset until deassert()
could force the core into debug state.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Uses chaining of command_registration structures to eliminate all
target_type register_callback routines. Exports the command_handler
registration arrays for those target types that are used by others.
There was a lot of needless handshaking overhead in the current
Cortex-A8 DCC/ITR operations, since the status read by each step
was discarded rather than letting the next step know it.
This shrinks the handshaking by: (a) passing status along from
previous steps, avoiding re-fetching; which enables the big win
(b) relying on a useful invariant: that the DSCR_INSTR_COMP bit
is set after every call to a DPM method.
A "reg sp_usr" call previously took 17 flushes; now it takes just 9.
This visibly speeds common operations like entry to debug state and
stepping, as well as "arm reg" and so on.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
This replaces two versions of register access functions. One
was commented out, and seemed to have uncertain intent. The
other was fairly new, and helped motivate the DPM framework
once I observed that the ARM11 was doing the very same ops.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
This implements the DPM interface for Cortex-A8 cores. It
also adds a synchronization operation to the DPM framework,
which is needed by the Cortex-A8 after CPSR writes.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Make various functions static, add some comments, report
vector catch as a flavor of DBG_REASON_BREAKPOINT, get
rid of needless/undesirable ARMV4_5_CORE_REG_MODE, etc.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Start using the arm_reg_current() call. This shrinks and speeds
the affected code. It can also prevent some coredumps coming from
invalid CPSR values ... the ARMV4_5_CORE_REG_MODE() macro returns
bogus registers if e.g. "Secure Monitor" mode isn't supported by
the current CPU.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Have arm_set_cpsr() handle the two core state flags, updating
the CPU state. This eliminates code in various debug_entry()
paths, and marginally improves handling of the J bit.
Catch and comment a few holes in the handling of the J bit on
ARM926ejs cores ... it's unlikely our users will care about
Jazelle mode, but we can at least warn of Impending Doom. If
anyone does use it, these breadcrumbs may help them to find
the right path through the code.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Define arm_reg_current() ... returning handle to a given register,
and encapsulating the current mode's register shadowing. It's got
one current use, for reporting the current register set to GDB.
This will let later patches clean up much ARMV4_5_CORE_REG_MODE()
nastiness, saving a bit of code.
Define and use arm_set_cpsr() ... initially it updates the cached
CPSR and sets up state used by arm_reg_current(), plus any SPSR
handle. (Later: can also set up for T and J bits.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Stash a pointer to the CPSR in the "struct arm", to help get rid
of the (common) references to its index in the register cache.
This removes almost all references to CPSR offsets outside of the
toplevel ARM code ... except a pair related to the current ARM11
"simulator" logic (which should be removable soonish).
This is a net minor code shrink of a few hundred bytes of object
code, and also makes the code more readable.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Implementations need to access the register struct they modify;
make it easier and less error-prone to identify the instance.
(This removes over 10% of the ARMV4_5_CORE_REG_MODE nastiness...)
Plus some minor fixes noted when making these updates: ARM7/ARM9
accessor methods should be static; don't leave CPSR wrongly marked
"dirty"; note significant XScale omissions in register handling;
and have armv4_5_build_reg_cache() record its result.
Rename "struct armv4_5_core_reg" as "struct arm_reg"; it's used
for more than those older architecture generations.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
The previous version never wrote dirty registers
for non-current CPU modes ... fix that.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
We *should* be able to read and write registers in any core mode,
instead of being stuck with whatever mode the core was when we
entered debug state. This patch makes them work.
Note that the current restore_context() only handles the current
mode; writing to other-mode registers is a NOP without a followup
patch fixing that. Also, that SPSR access needed some bugfixes;
it was confused with CPSR.
Secure monitor mode also seems dubious; there's probably more to
be done before that's sufficiently understood by the debugger.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Create a generic register_cache_invalidate(), and use it to
replace three all-but-identical core-specific routines:
- armv4_5_invalidate_core_regs()
- armv7m_invalidate_core_regs
- mips32_invalidate_core_regs() too.
Make cache->num_regs be unsigned, avoiding various errors.
Net code shrink and simplification.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
The examine() method has some conceptual breakage. Cope
with it by manually splitting out the run-once parts from
the after-each-reset parts ... this gets rid of memory
leaks and speeds up resets after the first one.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
We don't want an ARMv7-specific core state enumeration just to
add ThumbEE state. Update the generic stuff to handle that,
and replace the V7-specific bits with it.
For Cortex-A8: on debug entry, check both the T and J bits
instead of just the T bit. When the J bit is set, set the
right state and warn appropriately.
(And while we're at it, move the generic arm struct to the front
of the v7a structure, for somewhat better code generation.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
When we read the CPSR on debug entry, update the CPSR cache in all
cases, not just when the current processor state is User or System.
Plus minor cleanup of how the (too-many) other registers' cache
entries get updated.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
If the core doesn't provide an optimized version of this
method, provide one without core-specific optimizations.
Use this to make Cortex-A8 support the "arm reg" command.
Related: make the two register access methods properly static,
have the "set" log a "not halted" error too, and make sure
that the "valid" flag is set on successful reads.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
ARMv7-A doesn't need to duplicate all the standard ARM code
for register handling.
- Switch Cortex-A8 to use the standard register code
- Remove duplicated infrastructure from ARMv7-A
- Have ARMv7-A arch_state() show CPSR, like other ARMs
Add comments to show where the Cortex-A8 isn't actually doing
the right thing for register reads/writes, unless core happens
to be in the right mode to start with. (Looks like maybe there
may be generic confusion between saved/current PSR values in all
the ARM code ...)
Make related ARMv7-A and Cortex-A8 symbols properly static.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
It's used to flag cores with the "TrustZone" extension,
and is used in subsequent patches to set up support for
the registers shadowed by its new secure monitor mode.
The ARM1176 and Cortex-A8 both support this new mode.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Same deal: "register.h" got needlessly included all over the
place because of being in a few widely included headers.
So take it out of the header files which included it, and put
it in files which use it ... reduce needless interdependencies.
Also, don't need that extra "types.h" inclusion.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Most files in the tree seem to have ended up including this,
and *quite* needlessly ... only code implementing or using
breakpoints actually needs these declarations.
So take it out of the header files which included it, and put
it in files which use it ... reduce needless interdependencies.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
The arm7_9_checksum_memory() and arm7_9_blank_check_memory()
routines are not actually specific to the ARM7 and ARM9 core
generations ... they can work for any core which can run
algorithms using basic ARM (not Thumb) instructions.
Rename them; move the declarations to a more generic site;
likewise move the code (and tidy it a bit in the process).
NOTE: the blank_check() method falsely returned a success
status (0) on one error path, when the algorithm failed.
Fixed this bug.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Previously this flag was stored in "target_type", so that for example
if there were two ARM7TDMI targets in a scan chain, both would claim
to have been examined although only the first one actually had its
examine() method called.
Move this state to where it should have been in the first place, and
hide a method that didn't need exposure ... the flag is write-once.
Provide some doxygen. The examine() method is confusing, since it
isn't separating one-time setup from the after-each-reset stuff. And
the ARM7/ARM9 version is, somewhat undesirably, not leaving the debug
state alone after reset ... probably more of an issue for trace setup
than for watchpoints and breakpoints.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
David Brownell
Zachary T Welch