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>
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>
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>
