Xtensa cores may have registers of types/sizes not supported by the
gdbstub accessors. Ignore writes to such registers and return zero on
read, but always return correct register size, so that gdb on the other
side is able to access all registers in the packet holding unsupported
registers in the middle. This fixes gdb interaction with cores that have
vector/custom TIE registers.
Cc: qemu-stable@nongnu.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
In semihosting mode QEMU allows guest to read and write host file
descriptors directly, including descriptors 0..2, a.k.a. stdin, stdout
and stderr. Sometimes it's desirable to have semihosting console
controlled by -serial option, e.g. to connect it to network.
Add semihosting console to xtensa-semi.c, open it in the 'sim' machine
in the presence of -serial option and direct stdout and stderr to it
when it's present.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Return value of read/write simcalls is not calculated correctly in case
of operations crossing page boundary and in case of short reads/writes.
Read and write simcalls should return the size of data actually
read/written or -1 in case of error.
Cc: qemu-stable@nongnu.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Read and write simcalls map physical memory to access I/O buffers, but
'read' simcall need to map it for writing and 'write' simcall need to
map it for reading, i.e. the opposite of what they do now. Fix that.
Cc: qemu-stable@nongnu.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
So far xtensa provides fixed dummy argc/argv for the corresponding
semihosting calls. Now that there are semihosting_get_argc and
semihosting_get_arg, use them to pass actual command line arguments
to guest.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Make sure we have the BQL held when processing interrupts.
Reported-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Xtensa core may have a number of RAM and ROM areas configured. Record
their size and location from the core configuration overlay and
instantiate them as RAM regions in the SIM machine.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
When running certain HMP commands ("info registers", "info cpustats",
"info tlb", "nmi", "memsave" or dumping virtual memory) with the "none"
machine, QEMU crashes with a segmentation fault. This happens because the
"none" machine does not have any CPUs by default, but these HMP commands
did not check for a valid CPU pointer yet. Add such checks now, so we get
an error message about the missing CPU instead.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1484309555-1935-1-git-send-email-thuth@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
RER and WER are privileged instructions for accessing external
registers. External register address space is local to processor core.
There's no alignment requirements, addressable units are 32-bit wide
registers.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Configuration overlay does not explicitly say whether there are ICACHE
and DCACHE in the core. Current code uses XCHAL_[ID]CACHE_WAYS to detect
if corresponding cache option is enabled, but that's not correct: on
cores without cache these macros are defined as 1, not as 0.
Check XCHAL_[ID]CACHE_SIZE instead.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
There's no point in continuing translating guest instructions once an
unconditional exception is thrown.
There's also no point in updating pc before any instruction is
translated, don't do it.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Delimit each instruction that may access timers or IRQ state with
qemu_io_start/qemu_io_end, so that qemu-system-xtensa could be run with
-icount option.
Raise EXCP_YIELD after CCOMPARE reprogramming to let tcg_cpu_exec
recalculate how long this CPU is allowed to run.
RSR now may need to terminate TB, but it can't be done in RSR handler
because the same handler is used for XSR together with WSR handler, which
may also need to terminate TB. Change RSR and WSR handlers return type
to bool indicating whether TB termination is needed (RSR) or has been
done (WSR), and add TB termination after RSR/WSR dispatcher call.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Xtensa cores may have a register (CCOUNT) that counts core clock cycles.
It may also have a number of registers (CCOMPAREx); when CCOUNT value
passes the value of CCOMPAREx, timer interrupt x is raised.
Currently xtensa target counts a number of completed instructions and
assumes that for CCOUNT one instruction takes one cycle to complete.
It calls helper function to update CCOUNT register at every TB end and
raise timer interrupts. This scheme works very predictably and doesn't
have noticeable performance impact, but it is hard to use with multiple
synchronized processors, especially with coming MTTCG.
Derive CCOUNT from the virtual simulation time, QEMU_CLOCK_VIRTUAL.
Use native QEMU timers for CCOMPARE timers, one timer for each register.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
RUNSTALL signal stalls core execution while it's applied. It is widely
used in multicore configurations to control activity of additional
cores.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Xtensa cores may have two distinct addresses for the static vectors
group. Provide a function to select one of them.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
We have never has the concept of global TLB entries which would avoid
the flush so we never actually use this flag. Drop it and make clear
that tlb_flush is the sledge-hammer it has always been.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
[DG: ppc portions]
Acked-by: David Gibson <david@gibson.dropbear.id.au>
We've currently got 18 architectures in QEMU, and thus 18 target-xxx
folders in the root folder of the QEMU source tree. More architectures
(e.g. RISC-V, AVR) are likely to be included soon, too, so the main
folder of the QEMU sources slowly gets quite overcrowded with the
target-xxx folders.
To disburden the main folder a little bit, let's move the target-xxx
folders into a dedicated target/ folder, so that target-xxx/ simply
becomes target/xxx/ instead.
Acked-by: Laurent Vivier <laurent@vivier.eu> [m68k part]
Acked-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> [tricore part]
Acked-by: Michael Walle <michael@walle.cc> [lm32 part]
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> [s390x part]
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> [s390x part]
Acked-by: Eduardo Habkost <ehabkost@redhat.com> [i386 part]
Acked-by: Artyom Tarasenko <atar4qemu@gmail.com> [sparc part]
Acked-by: Richard Henderson <rth@twiddle.net> [alpha part]
Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa part]
Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [ppc part]
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> [crisµblaze part]
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> [unicore32 part]
Signed-off-by: Thomas Huth <thuth@redhat.com>
Max Filippov
Peter Maydell
Alex Bennée
Thomas Huth
Richard Henderson