qemu/target/lm32
Markus Armbruster 90c84c5600 qom/cpu: Simplify how CPUClass:cpu_dump_state() prints
CPUClass method dump_statistics() takes an fprintf()-like callback and
a FILE * to pass to it.  Most callers pass fprintf() and stderr.
log_cpu_state() passes fprintf() and qemu_log_file.
hmp_info_registers() passes monitor_fprintf() and the current monitor
cast to FILE *.  monitor_fprintf() casts it right back, and is
otherwise identical to monitor_printf().

The callback gets passed around a lot, which is tiresome.  The
type-punning around monitor_fprintf() is ugly.

Drop the callback, and call qemu_fprintf() instead.  Also gets rid of
the type-punning, since qemu_fprintf() takes NULL instead of the
current monitor cast to FILE *.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-15-armbru@redhat.com>
2019-04-18 22:18:59 +02:00
..
Makefile.objs
README
TODO
cpu-qom.h
cpu.c target: Simplify how the TARGET_cpu_list() print 2019-04-18 22:18:59 +02:00
cpu.h qom/cpu: Simplify how CPUClass:cpu_dump_state() prints 2019-04-18 22:18:59 +02:00
gdbstub.c
helper.c accel/tcg: add size paremeter in tlb_fill() 2018-01-25 16:02:24 +01:00
helper.h
lm32-semi.c
machine.c
op_helper.c lm32: take BQL before writing IP/IM register 2018-05-21 13:37:12 +02:00
translate.c qom/cpu: Simplify how CPUClass:cpu_dump_state() prints 2019-04-18 22:18:59 +02:00

README

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);