Changes the jtag_interface->register_callbacks field to a list of
commands to be registered.  Changes callback to invocation of
register_commands() with that command registration list.  Removes all
JTAG interface driver register_command callback functions, which the
previous commits had converted into identical calls.

Use register_commands() with command registration array.

Use register commands with command registration array.

Use register_commands() with command registration array.

Use register_commands() with a command registration array.

Use register_commands() with command registration array.

Use register_commands() with command registration array.

Use register_commands() with a command registration array.

Use register_commands() with command registration array.
---
This module was broken by previous changes, but no one has complained.
Are there still users for this modules?

Uses register_commands() with command registration array.

Use register_commands() with command_registration array.

Remove register_callbacks from pld_device structure, using an array
of command_registration records instead.

Updates core PLD and virtex2 commands to use register_commands().

Use register_commands() for registering {,x}svf commands.

Converts server directory to use new command registration paradigm.

Use register_commands() for logging callbacks.  Improve help and add
proper usage.

Use table instead of individual calls.  Add proper usage information.

Use register_commands() for top-level version and init command.

Use the new command registration chaining capabilities to eliminate
the foo_register_commands helper, folding its remaining command
handler setup into the hello_command_handlers registration array.

Use new register_commands() with command registration table.

Rewrite the magical 'unknown' command in C as a Jim handler, allowing
it to dispatch commands to any level in the tree.

Allow other modules to find a command, primarily for the purpose of
registering and unregistering subcommands.

Move command context acquisition to current_command_context() for re-use.

Adds the ability to chain registration structures.  Modules can define a
command with the 'chain' and 'num_chain' fields defined in their
registration table, and the register_commands() function will initialize
these commands.  If the registration record creates a new command, then
the chained commands are created under it; otherwise, they are created
in the same context as the other commands (i.e. the parent argument).

Split out the handler registration into its own function, and add a
few obviously missing NULL pointer error checking.

Use register_commands() to register low-level command handlers,
adding a builtin_command_handlers declaration that is easy to understand.
Splits help and usage information into their appropriate fields.

Adds the usage command, to display usage information for commands.
The output for this command will remain erronenously empty until
commands are updated to use these new coventions.

The register_commands API takes multiple commands in one call, allowing
modules to declare and pass a much simpler (and more explicit) array of
command_registration records.

Add a structure to encapsulate command registration information, rather
than passing them all as parameters.  Enables further API changes that
require additional required or optional parameters.

Updates the register_command API and COMMAND_REGISTER macro to use it,
along with their documentation.

Replaces direct calls to register_command() with a macro, to allow
its parameters to be changed and callers updated in phases.

Provides a migration path for the widely used register_command API,
which needs to be updated to provide new functionality.

This macro allows the API to change without having to update all of its
callers at the same time.

Fix a couple of layering violations missed in the last round.
Add missing comment headers.

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>

The previous implementation was unnecessarily complex. Get rid of the loops,
let vsnprintf() tell us directly how much storage we need and allocate that. A
second pass writes the actual string. Also add a va_end() that was missing.
This should be much faster for large strings and less wasteful for small ones.

A quirk that has been retained is that some callers patch in a newline at the
end of the returned string and depend on alloc_vprintf to allocate at least
one byte extra.

Signed-off-by: Andreas Fritiofson <andreas.fritiofson@gmail.com>
Signed-off-by: Zachary T Welch <zw@superlucidity.net>

Update build rules to skip the PDF unless the TeX has been created.
Also, fixes a warning regarding pattern rules being a GNU make trick.