@item @code{testee} -- a dummy target for cases without a real CPU, e.g. CPLD.
@item @code{xscale} -- this is actually an architecture,
not a CPU type. It is based on the ARMv5 architecture.
+@item @code{xtensa} -- this is a generic Cadence/Tensilica Xtensa core.
@end itemize
@end deffn
protocol SWIM, @pxref{swimtransport,,SWIM}.
@section Xtensa Architecture
-Xtensa processors are based on a modular, highly flexible 32-bit RISC architecture
-that can easily scale from a tiny, cache-less controller or task engine to a high-performance
-SIMD/VLIW DSP provided by Cadence.
-@url{https://www.cadence.com/en_US/home/tools/ip/tensilica-ip/tensilica-xtensa-controllers-and-extensible-processors.html}.
-OpenOCD supports generic Xtensa processors implementation which can be customized by
-simply providing vendor-specific core configuration which controls every configurable
+Xtensa is a highly-customizable, user-extensible microprocessor and DSP
+architecture for complex embedded systems provided by Cadence Design
+Systems, Inc. See the
+@uref{https://www.cadence.com/en_US/home/tools/ip/tensilica-ip.html, Tensilica IP}
+website for additional information and documentation.
+
+OpenOCD supports generic Xtensa processor implementations which can be customized by
+providing a core-specific configuration file which describes every enabled
Xtensa architecture option, e.g. number of address registers, exceptions, reduced
-size instructions support, memory banks configuration etc. Also OpenOCD supports SMP
-configurations for Xtensa processors with any number of cores and allows to configure
-their debug signals interconnection (so-called "break/stall networks") which control how
-debug signals are distributed among cores. Xtensa "break networks" are compatible with
-ARM's Cross Trigger Interface (CTI). For debugging code on Xtensa chips OpenOCD
-uses JTAG protocol. Currently OpenOCD implements several Epsressif Xtensa-based chips of
+size instructions support, memory banks configuration etc. OpenOCD also supports SMP
+configurations for Xtensa processors with any number of cores and allows configuring
+their debug interconnect (termed "break/stall networks"), which control how debug
+signals are distributed among cores. Xtensa "break networks" are compatible with
+ARM's Cross Trigger Interface (CTI). OpenOCD implements both generic Xtensa targets
+as well as several Espressif Xtensa-based chips from the
@uref{https://www.espressif.com/en/products/socs, ESP32 family}.
-@subsection General Xtensa Commands
+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
@deffn {Command} {xtensa set_permissive} (0|1)
By default accessing memory beyond defined regions is forbidden. This commnd controls memory access address check.
When set to (1), skips access controls and address range check before read/write memory.
@end deffn
-@deffn {Command} {xtensa maskisr} (on|off)
-Selects whether interrupts will be disabled during stepping over single instruction. The default configuration is (off).
-@end deffn
-
@deffn {Command} {xtensa smpbreak} [none|breakinout|runstall] | [BreakIn] [BreakOut] [RunStallIn] [DebugModeOut]
Configures debug signals connection ("break network") for currently selected core.
@itemize @bullet
@end itemize
@end deffn
+@deffn {Command} {xtensa exe} <ascii-encoded hexadecimal instruction bytes>
+Execute arbitrary instruction(s) provided as an ascii string. The string represents an integer
+number of instruction bytes, thus its length must be even.
+@end deffn
+
+@subsection Xtensa Performance Monitor Configuration
+
@deffn {Command} {xtensa perfmon_enable} <counter_id> <select> [mask] [kernelcnt] [tracelevel]
Enable and start performance counter.
@itemize @bullet
Dump performance counter value. If no argument specified, dumps all counters.
@end deffn
+@subsection Xtensa Trace Configuration
+
@deffn {Command} {xtensa tracestart} [pc <pcval>/[<maskbitcount>]] [after <n> [ins|words]]
Set up and start a HW trace. Optionally set PC address range to trigger tracing stop when reached during program execution.
This command also allows to specify the amount of data to capture after stop trigger activation.
projects / fw / openocd / blobdiff