qemu/target/lm32
Philippe Mathieu-Daudé 6b5fe13786 semihosting: Move include/hw/semihosting/ -> include/semihosting/
We want to move the semihosting code out of hw/ in the next patch.

This patch contains the mechanical steps, created using:

  $ git mv include/hw/semihosting/ include/
  $ sed -i s,hw/semihosting,semihosting, $(git grep -l hw/semihosting)

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210226131356.3964782-2-f4bug@amsat.org>
Message-Id: <20210305135451.15427-2-alex.bennee@linaro.org>
2021-03-10 15:34:12 +00:00
..
cpu-param.h tcg: Split out target/arch/cpu-param.h 2019-06-10 07:03:34 -07:00
cpu-qom.h qom: Remove module_obj_name parameter from OBJECT_DECLARE* macros 2020-09-18 14:12:32 -04:00
cpu.c cpu: tcg_ops: move to tcg-cpu-ops.h, keep a pointer in CPUClass 2021-02-05 10:24:15 -10:00
cpu.h nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
gdbstub.c nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
helper.c semihosting: Move include/hw/semihosting/ -> include/semihosting/ 2021-03-10 15:34:12 +00:00
helper.h
lm32-semi.c
machine.c Include hw/boards.h a bit less 2019-08-16 13:31:53 +02:00
meson.build meson: target 2020-08-21 06:30:35 -04:00
op_helper.c sysemu: Split sysemu/runstate.h off sysemu/sysemu.h 2019-08-16 13:37:36 +02:00
README
TODO
translate.c exec: Move TranslationBlock typedef to qemu/typedefs.h 2021-02-18 08:19:08 +00:00

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);