qemu/target-lm32
Peter Crosthwaite d49190c420 disas: Remove uses of CPU env
disas does not need to access the CPU env for any reason. Change the
APIs to accept CPU pointers instead. Small change pattern needs to be
applied to all target translate.c. This brings us closer to making
disas.o a common-obj and less architecture specific in general.

Cc: Richard Henderson <rth@twiddle.net>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: "Edgar E. Iglesias" <edgar.iglesias@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Michael Walle <michael@walle.cc>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Leon Alrae <leon.alrae@imgtec.com>
Cc: Jia Liu <proljc@gmail.com>
Cc: Alexander Graf <agraf@suse.de>
Cc: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Acked-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-06-22 17:40:01 +02:00
..
cpu-qom.h target-lm32: Use cpu_exec_interrupt qom hook 2014-09-25 18:54:22 +01:00
cpu.c gdbstub: Allow target CPUs to specify watchpoint STOP_BEFORE_ACCESS flag 2014-10-06 14:25:43 +01:00
cpu.h cpu: Make cpu_init() return QOM CPUState object 2015-03-10 17:33:51 +01:00
gdbstub.c cpu: Introduce CPUClass::gdb_{read,write}_register() 2013-07-27 00:04:17 +02:00
helper.c semihosting: create SemihostingConfig structure and semihost.h 2015-06-19 14:17:45 +01:00
helper.h tcg: Invert the inclusion of helper.h 2014-05-28 09:33:54 -07:00
lm32-semi.c tcg: Invert the inclusion of helper.h 2014-05-28 09:33:54 -07:00
machine.c savevm: Remove all the unneeded version_minimum_id_old (rest) 2014-05-14 15:24:51 +02:00
Makefile.objs target-lm32: add semihosting support 2014-05-24 19:42:29 +02:00
op_helper.c vl: allow other threads to do qemu_system_vmstop_request 2014-06-23 16:36:13 +08:00
README lm32: remove lm32_sys 2014-05-24 19:43:52 +02:00
TODO target-lm32: add breakpoint/watchpoint support 2014-02-04 19:47:06 +01:00
translate.c disas: Remove uses of CPU env 2015-06-22 17:40:01 +02:00

LatticeMico32 target
--------------------

General
-------
All opcodes including the JUART CSRs are supported.


JTAG UART
---------
JTAG UART is routed to a serial console device. For the current boards it
is the second one. Ie to enable it in the qemu virtual console window use
the following command line parameters:
  -serial vc -serial vc
This will make serial0 (the lm32_uart) and serial1 (the JTAG UART)
available as virtual consoles.


Semihosting
-----------
Semihosting on this target is supported. Some system calls like read, write
and exit are executed on the host if semihosting is enabled. See
target/lm32-semi.c for all supported system calls. Emulation aware programs
can use this mechanism to shut down the virtual machine and print to the
host console. See the tcg tests for an example.


Special instructions
--------------------
The translation recognizes one special instruction to halt the cpu:
  and r0, r0, r0
On real hardware this instruction is a nop. It is not used by GCC and
should (hopefully) not be used within hand-crafted assembly.
Insert this instruction in your idle loop to reduce the cpu load on the
host.


Ignoring the MSB of the address bus
-----------------------------------
Some SoC ignores the MSB on the address bus. Thus creating a shadow memory
area. As a general rule, 0x00000000-0x7fffffff is cached, whereas
0x80000000-0xffffffff is not cached and used to access IO devices. This
behaviour can be enabled with:
  cpu_lm32_set_phys_msb_ignore(env, 1);