+OCD sessions for Xtensa processor and DSP targets are accessed via the Xtensa
+Debug Module (XDM), which provides external connectivity either through a
+traditional JTAG interface or an ARM DAP interface. If used, the DAP interface
+can control Xtensa targets through JTAG or SWD probes.
+
+@subsection Xtensa Core Configuration
+
+Due to the high level of configurability in Xtensa cores, the Xtensa target
+configuration comprises two categories:
+
+@enumerate
+@item Base Xtensa support common to all core configurations, and
+@item Core-specific support as configured for individual cores.
+@end enumerate
+
+All common Xtensa support is built into the OpenOCD Xtensa target layer and
+is enabled through a combination of TCL scripts: the target-specific
+@file{target/xtensa.cfg} and a board-specific @file{board/xtensa-*.cfg},
+similar to other target architectures.
+
+Importantly, core-specific configuration information must be provided by
+the user, and takes the form of an @file{xtensa-core-XXX.cfg} TCL script that
+defines the core's configurable features through a series of Xtensa
+configuration commands (detailed below).
+
+This core-specific @file{xtensa-core-XXX.cfg} file is typically either:
+
+@itemize @bullet
+@item Located within the Xtensa core configuration build as
+@file{src/config/xtensa-core-openocd.cfg}, or
+@item Generated by running the command @code{xt-gdb --dump-oocd-config}
+from the Xtensa processor tool-chain's command-line tools.
+@end itemize
+
+NOTE: @file{xtensa-core-XXX.cfg} must match the target Xtensa hardware
+connected to OpenOCD.
+
+Some example Xtensa configurations are bundled with OpenOCD for reference:
+@itemize @bullet
+@item Cadence Palladium VDebug emulation target. The user can combine their
+@file{xtensa-core-XXX.cfg} with the provided
+@file{board/xtensa-palladium-vdebug.cfg} to debug an emulated Xtensa RTL design.
+@item NXP MIMXRT685-EVK evaluation kit. The relevant configuration files are
+@file{board/xtensa-rt685-jlink.cfg} and @file{board/xtensa-core-nxp_rt600.cfg}.
+Additional information is provided by
+@uref{https://www.nxp.com/design/development-boards/i-mx-evaluation-and-development-boards/i-mx-rt600-evaluation-kit:MIMXRT685-EVK,
+NXP}.
+@end itemize
+
+@subsection Xtensa Configuration Commands
+
+@deffn {Command} {xtensa xtdef} (@option{LX}|@option{NX})
+Configure the Xtensa target architecture. Currently, Xtensa support is limited
+to LX6, LX7, and NX cores.
+@end deffn
+
+@deffn {Command} {xtensa xtopt} option value
+Configure Xtensa target options that are relevant to the debug subsystem.
+@var{option} is one of: @option{arnum}, @option{windowed},
+@option{cpenable}, @option{exceptions}, @option{intnum}, @option{hipriints},
+@option{excmlevel}, @option{intlevels}, @option{debuglevel},
+@option{ibreaknum}, or @option{dbreaknum}. @var{value} is an integer with
+the exact range determined by each particular option.
+
+NOTE: Some options are specific to Xtensa LX or Xtensa NX architecture, while
+others may be common to both but have different valid ranges.
+@end deffn
+
+@deffn {Command} {xtensa xtmem} (@option{iram}|@option{dram}|@option{sram}|@option{irom}|@option{drom}|@option{srom}) baseaddr bytes
+Configure Xtensa target memory. Memory type determines access rights,
+where RAMs are read/write while ROMs are read-only. @var{baseaddr} and
+@var{bytes} are both integers, typically hexadecimal and decimal, respectively.
+@end deffn
+
+@deffn {Command} {xtensa xtmem} (@option{icache}|@option{dcache}) linebytes cachebytes ways [writeback]
+Configure Xtensa processor cache. All parameters are required except for
+the optional @option{writeback} parameter; all are integers.
+@end deffn
+
+@deffn {Command} {xtensa xtmpu} numfgseg minsegsz lockable execonly
+Configure an Xtensa Memory Protection Unit (MPU). MPUs can restrict access
+and/or control cacheability of specific address ranges, but are lighter-weight
+than a full traditional MMU. All parameters are required; all are integers.
+@end deffn
+
+@deffn {Command} {xtensa xtmmu} numirefillentries numdrefillentries
+(Xtensa-LX only) Configure an Xtensa Memory Management Unit (MMU). Both
+parameters are required; both are integers.
+@end deffn
+
+@deffn {Command} {xtensa xtregs} numregs
+Configure the total number of registers for the Xtensa core. Configuration
+logic expects to subsequently process this number of @code{xtensa xtreg}
+definitions. @var{numregs} is an integer.
+@end deffn
+
+@deffn {Command} {xtensa xtregfmt} (@option{sparse}|@option{contiguous}) [general]
+Configure the type of register map used by GDB to access the Xtensa core.
+Generic Xtensa tools (e.g. xt-gdb) require @option{sparse} mapping (default) while
+Espressif tools expect @option{contiguous} mapping. Contiguous mapping takes an
+additional, optional integer parameter @option{numgregs}, which specifies the number
+of general registers used in handling g/G packets.
+@end deffn
+
+@deffn {Command} {xtensa xtreg} name offset
+Configure an Xtensa core register. All core registers are 32 bits wide,
+while TIE and user registers may have variable widths. @var{name} is a
+character string identifier while @var{offset} is a hexadecimal integer.
+@end deffn
+
+@subsection Xtensa Operation Commands
+
+@deffn {Command} {xtensa maskisr} (@option{on}|@option{off})
+(Xtensa-LX only) Mask or unmask Xtensa interrupts during instruction step.
+When masked, an interrupt that occurs during a step operation is handled and
+its ISR is executed, with the user's debug session returning after potentially
+executing many instructions. When unmasked, a triggered interrupt will result
+in execution progressing the requested number of instructions into the relevant
+vector/ISR code.
+@end deffn