Commit Graph

9 Commits

Author SHA1 Message Date
Stafford Horne
6b4bbd6aeb openrisc/cputimer: Perparation for Multicore
In order to support multicore system we move some of the previously
static state variables into the state of each core.

On the other hand in order to allow timers to be synced between each
code the ttcr (tick timer count register) is moved out of the core.
This is not as per real hardware spec which has a separate timer counter
per core, but it seems the most simple way to keep each clock in sync.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-10-21 06:35:47 +09:00
Stafford Horne
f4d1414a93 target/openrisc: Support non-busy idle state using PMR SPR
The OpenRISC architecture has the Power Management Register (PMR)
special purpose register to manage cpu power states.  The interesting
modes are:

 * Doze Mode (DME) - Stop cpu except timer & pic - wake on interrupt
 * Sleep Mode (SME) - Stop cpu and all units - wake on interrupt
 * Suspend Model (SUME) - Stop cpu and all units - wake on reset

The linux kernel will set DME when idle.

This patch implements the PMR SPR and halts the qemu cpu when there is a
change to DME or SME.  This means that openrisc qemu in no longer peggs
a host cpu at 100%.

In order for this to work we need to kick the CPU when timers are
expired.  Update the cpu timer to kick the cpu upon each timer event.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-05-04 09:39:14 +09:00
Stafford Horne
acf57591c0 target/openrisc: Implement full vmstate serialization
Previously serialization did not persist the tlb, timer, pic and other
key state items.  This meant snapshotting and restoring a running os
would crash. After adding these I am able to take snapshots of a
running linux os and restore at a later time.

I am currently not trying to maintain capatibility with older versions
as I do not believe this really worked before or anyone used it.

Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-05-04 09:39:14 +09:00
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
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
6f7332ba71 target/openrisc: Represent MACHI:MACLO as a single unit
Significantly simplifies the implementation of the use of MAC.

Reviewed-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
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
Richard Henderson
930c3d0074 target/openrisc: Implement lwa, swa
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