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>
This finishes the basic switchover to the new register code,
for everything except the debug registers. (And maybe we
shouldn't have a cache for *those* which works this way...)
The context save/restore code now uses the new code, but
it's in a slightly different sequence. That should be fine
since the R0/PC/CPSR stuff is all that really matters (and
if we can update those, we can update the rest).
Now there's no longer a way any code can be confused about
which copy of "r1" (etc) to use.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
As with single stepping, the previous stuff was needed because
the ARM11 code wasn't using the standard ARM base type and
register access ... but now those mechanisms work, so we can
switch out that special-purpose glue, in favor of the more
thoroughly tested/capable "standard" code.
Fixes a bug in the resume() implementation: it wasn't handling
two of its arguments correctly, preventing the "flash erase_check"
algorithm from working. (This code needs a *subsequent* update
for correct register handling, though... removing the confusion
about which "r2", for example, to use.)
This should resolve some "FIXME" comments too, for Thumb and
processor mode support. It also gets rid of a nasty exit()
call; servers should only have *clean* shutdown paths.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
The previous stuff was needed because the ARM11 code wasn't using
the standard ARM base type and register access ... but now those
mechanisms work, so we can switch out that special-purpose glue.
This should resolve all the "FIXME -- handle Thumb single stepping"
comments too, and properly handle the processor's mode. (Modulo
the issue that this code doesn't yet handle two-byte breakpoints.)
Clarify the comments about the the hardware single stepping. When
we eventually share breakpoint code with Cortex-A8, we can just make
that be the default on cores which support it. We may still want an
override command, not just to facilitate testing but to cope with
"instruction address mismatch" not quite being true single-step.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
This provides "standard" ARM register support -- with twenty or
more shadow registers on top of what this code now handles, but
properly associated with the various core modes -- parallel to
the current register code. That is, the current code is stilil
managing the "current" registers; the new code shadows them.
You can see all the registers with "arm reg", modify the shadows
like "r8_fiq" or "sp_abt" with "reg", and see them get properly
written back when you step. (Just don't do that with any of the
registers managed by the "old" code ...)
It also switches to using more standard code, relying on those
standard registers, in two places: (a) the poll status display,
which now shows core state (ARM/Thumb/...) and mode (Supervisor,
IRQ, etc); and (b) GDB register access.
So it's not a full migration, there are warts -- every place that
touches the old register cache is a potential bug -- but it's a
small more-or-less-comprehensible step that's even somewhat useful.
Later patches complete the migration.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
This was a private mechanism to snapshot registers before leaving
debug state, and then on reentry to optionally display what changed.
It was coupled to the private register cache, which won't be sticking
around in that form for much longer. Remove (instead of teaching
it how to handle *all* the registers).
(The idea is interesting, but we ought to be able to implement
this in a generic way. Ideally through Tcl scripts that can
automatically be invoked following debug entry...)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
This is a very thin layer over some of the current ARM11
debug TAP utilities. The layer isn't yet hooked up.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
First version of interface for sharing code between ARMv6 and ARMv7a
debug modules ... now the architecture includes debug support. (Not
the same as for the trimmed-down v7m or v6m though!) This is a first
version of an interface that will let the ARM11 and Cortex-A8 support
share code, features, and bugfixes. Based on existing code from both
of those cores.
The ARM v7-AR architecture specification calls this commonality the
"Debug Programmer's Model (DPM)", which seemed to be an appropriate
acronym -- a TLA even! -- for use in our code. Made it so. :)
The initial scope of this just supports register access, and is geared
towards supporting top level "struct arm" mechanisms. Later, things
like breakpoint and watchpoint support should be included.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
For now there's no point in saving this stuff after examine()
checks it out as OK. Ditto exporting symbols that aren't
used outside of the module which defines them. In fact, those
two things needlessly complicate the code...
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Make this code look more like the rest of the OpenOCD code.
- Use calloc() directly, not NEW() ... and fix some potential
memory leaks while we're at it.
- Remove FNC_INFO ... it's a NOP that just clutters things,
and it's trivial for developers to add tracing as needed.
- Replace FNC_INFO_NOTIMPLEMENTED with LOG_WARNING calls;
ditto. And stop having those call sites wrongly succeed!
- Waste less space with the CHECK_RETVAL() macro.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
This will allow data to be allocated in read only
memory instead of on the stack. Speeds things up
and reduces stack usage.
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
buf_set_u32() operated on an uninitialized stack
variable with non-byte boundaries, which led to
warnings about reading uninitialized stack.
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
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>
We don't need to use size_t in these places; so it's easy
to be rid of the need for this #ifdef and its MS-derived
portability problems.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
With -O3 when inlining aggressively the total stack usage will
be the sum of many fn's, which can easily get out of hand.
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
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>
Minor cleanup of ARM11 register handling: remove disabled
register hooks. This should all be handled by shared code,
and this stuff is just clutter.
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>
Remove two commands that were documented as "debug commands"
and where "you probably don't want to use this". We never
intended to support them, and at least one problem report
boiled down to using this when it shouldn't have been used.
Update the docs on the existing register commands to talk a
bit more about register access and cache behavior. (Those
debug commands existed largely to *bypass* the cache.) And
fix some minor doc goofs that snuck in with recent changes,
renaming "armv4_5" as "arm" and "arm9tdmi" as "arm9".
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>
Just pre-allocate memory for the cached register value.
Shrinks heap overhead; increases locality-of-reference.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Combine register names with other per-register data into a
single template structure. This saves space, and makes it
easier to change how registers get handled (by shrinking
the number of places that care about cache indices).
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>
The only way ARMv7-A modes differ from ARMv4/ARMv5 flavors
is that v7-A is allowed to include "Secure monitor" support.
That's now handled by our standard top-level ARM code ... so
phase out the stuff that's specific to ARMv7-A.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Removing the fast command eliminates the fast_and_dangerous global,
which was used only by arm7_9_common as an initializer. The command
is not called in the tree; instead, more explicit commands are used.
The jim_global_long function was not used anywhere in the tree.
Rewrite arm11_handle_bool to provide a generic on/off command helper.
Refactors COMMAND_PARSE_BOOL to use new command_parse_bool helper,
which gets reused by the new command_parse_bool_any helper.
This later helper is called by the new command helper function to
accepts any on/off, enable/disable, true/false, yes/no, or 0/1 parameter.
Updates all command parsing of simple "enable" and "disable" arguments.
A few case in the tree use a tri-state or extended arguments, which
cannot use this simple macro.
Simlifies the xscale icache/dcache command handler logic.
Change the layout to show the "Secure Monitor" registers too,
when they're present.
Instead of lining registers for each of six (or seven) modes up
in adjacent vertical columns, display each mode's registers (or
shadows) in a single block, avoiding duplicate value displays.
This also lets us shrink the line length to fits in standard 80
character lines ... six or seven 18-character columns can't fit.
Relabel "r13" as "sp", so it's more meaningful.
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>
Zachary T Welch
David Brownell
Jerry Ling
Øyvind Harboe