Commit Graph

5 Commits

Author SHA1 Message Date
Stafford Horne d89e71e873 target/openrisc: implement shadow registers
Shadow registers are part of the openrisc spec along with sr[cid], as
part of the fast context switching feature.  When exceptions occur,
instead of having to save registers to the stack if enabled the CID will
increment and a new set of registers will be available.

This patch only implements shadow registers which can be used as extra
scratch registers via the mfspr and mtspr if required.  This is
implemented in a way where it would be easy to add on the fast context
switching, currently cid is hardcoded to 0.

This is need for openrisc linux smp kernels to boot correctly.

Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-05-04 09:39:01 +09:00
Richard Henderson a01deb36a6 target/openrisc: Tidy handling of delayed branches
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-02-14 08:15:00 +11:00
Richard Henderson 24c328521b target/openrisc: Tidy ppc/npc implementation
The NPC SPR is really only supposed to be used for FPGA debugging.
It contains the same contents as PC, unless one plays games.  Follow
the or1ksim implementation in flushing delayed branch state when it
is changed.

The PPC SPR need not be updated every instruction, merely when we
exit the TB or attempt to read its contents.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-02-14 08:15:00 +11:00
Richard Henderson 84775c43f3 target/openrisc: Keep SR_F in a separate variable
This avoids having to keep merging and extracting the flag from SR.

Reviewed-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-02-14 08:14:59 +11:00
Thomas Huth fcf5ef2ab5 Move target-* CPU file into a target/ folder
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> [cris&microblaze part]
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> [unicore32 part]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2016-12-20 21:52:12 +01:00