This change takes the CPUPPCState 'quiesced' field added for powernv
hardware CPU core controls (used to stop and start cores), and extends
it to spapr to model the "RTAS stopped" state. This prevents the
schedulers attempting to run stopped CPUs unexpectedly, which can cause
hangs and possibly other unexpected behaviour.
The detail of the problematic situation is this:
A KVM spapr guest boots with all secondary CPUs defined to be in the
"RTAS stopped" state. In this state, the CPU is only responsive to the
start-cpu RTAS call. This behaviour is modeled in QEMU with the
start_powered_off feature, which sets ->halted on secondary CPUs at
boot. ->halted=true looks like an idle / sleep / power-save state which
typically is responsive to asynchronous interrupts, but spapr clears
wake-on-interrupt bits in the LPCR SPR. This more-or-less works.
Commit e8291ec16da8 ("target/ppc: fix timebase register reset state")
recently caused the decrementer to expire sooner at boot, causing a
decrementer exception on secondary CPUs in RTAS stopped state. This
was not a problem on TCG, but KVM limits how a guest can modify LPCR, in
particular it prevents the clearing of wake-on-interrupt bits, and so in
the course of CPU register synchronisation, the LPCR as set by spapr to
model the RTAS stopped state is overwritten with KVM's LPCR value, and
that then causes QEMU's interrupt code to notice the expired decrementer
exception, turn that into an interrupt, and set CPU_INTERRUPT_HARD.
That causes the CPU to be kicked, and the KVM vCPU thread to loop
calling kvm_cpu_exec(). kvm_cpu_exec() calls
kvm_arch_process_async_events(), which on ppc just returns ->halted.
This is still true, so it returns immediately with EXCP_HLT, and the
vCPU never goes to sleep because qemu_wait_io_event() sees
CPU_INTERRUPT_HARD is set. All this while the vCPU holds the bql. This
causes the boot CPU to eventually lock up when it needs the bql.
So make 'quiesced' represent the "RTAS stopped" state, and have it
explicitly not respond to exceptions (interrupt conditions) rather than
rely on machine register state to model that state. This matches the
powernv quiesced state very well because it essentially turns off the
CPU core via a side-band control unit.
There are still issues with QEMU and KVM idea of LPCR diverging and that
is quite ugly and fragile that should be fixed. spapr should synchronize
its LPCR properly with KVM, and not try to use values that KVM does not
support.
Reported-by: Misbah Anjum N <misanjum@linux.ibm.com>
Tested-by: Misbah Anjum N <misanjum@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Move helper_attn(), helper_scv() and helper_pminsn() to
tcg-excp_helper.c.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-ID: <20250127102620.39159-15-philmd@linaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
In order to move TCG specific code dependent on powerpc_excp()
in the next commit, expose its prototype in "internal.h".
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-ID: <20250127102620.39159-14-philmd@linaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Fix style in do_rfi() before moving the code around.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-ID: <20250127102620.39159-13-philmd@linaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Move helpers common to system/user emulation to tcg-excp_helper.c.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-ID: <20250127102620.39159-12-philmd@linaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Move exception helpers to tcg-excp_helper.c so they are
only built when TCG is selected. Preprocessor guards
are added for some helpers unused when CONFIG_USER_ONLY.
[npiggin: mention USER_ONLY change]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20250127102620.39159-10-philmd@linaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Introduced in commit db789c6cd33 ("ppc: Provide basic
raise_exception_* functions"), raise_exception_ra() has
never been used. Remove as dead code.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-ID: <20250127102620.39159-9-philmd@linaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Expose powerpc_checkstop() prototype, and move it to
tcg-excp_helper.c, only built when TCG is available.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-ID: <20250127102620.39159-8-philmd@linaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20250127102620.39159-7-philmd@linaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-ID: <20250127102620.39159-6-philmd@linaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Move the TCGCPUOps handlers to a new unit: tcg-excp_helper.c,
only built when TCG is selected.
See in target/ppc/cpu_init.c:
#ifdef CONFIG_TCG
static const TCGCPUOps ppc_tcg_ops = {
...
.do_unaligned_access = ppc_cpu_do_unaligned_access,
.do_transaction_failed = ppc_cpu_do_transaction_failed,
.debug_excp_handler = ppc_cpu_debug_excp_handler,
.debug_check_breakpoint = ppc_cpu_debug_check_breakpoint,
.debug_check_watchpoint = ppc_cpu_debug_check_watchpoint,
};
#endif /* CONFIG_TCG */
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-ID: <20250127102620.39159-5-philmd@linaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
We are going to move code calling ppc_ldl_code() out of
excp_helper.c where it is defined. Expose its declaration
for few commits, until eventually making it static again
once everything is moved.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-ID: <20250127102620.39159-4-philmd@linaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Headers in include/sysemu/ are not only related to system
*emulation*, they are also used by virtualization. Rename
as system/ which is clearer.
Files renamed manually then mechanical change using sed tool.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Lei Yang <leiyang@redhat.com>
Message-Id: <20241203172445.28576-1-philmd@linaro.org>
The ppc (pnv and spapr) NMI injection code does not go through the
asynchronous interrupt path and set a bit in env->pending_interrupts
and raise an interrupt request that the cpu_exec() loop can see.
Instead it injects the exception directly into registers.
This can lead to cpu_exec() missing that the thread has work to do,
if a NMI is injected while it was idle.
Fix this by clearing halted when injecting the interrupt. Probably
NMI injection should be reworked to use the interrupt request interface,
but this seems to work as a minimal fix.
Fixes: 3431648272d3 ("spapr: Add support for new NMI interface")
Reviewed-by: Glenn Miles <milesg@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
ppc_excp_apply_ail has multiple if-checks for ail which is un-necessary.
Combine them as appropriate.
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
As previously done for arch specific handlers, simplify var usage in
ppc_next_unmasked_interrupt by caching the env->pending_interrupts and
env->spr[SPR_LPCR] in local vars and using it later at multiple places.
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Like p8 and p9, simplifying p7 exception handling rotuines to avoid
un-necessary multiple indirect accesses to env->pending_interrupts and
env->spr[SPR_LPCR].
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Most of the p8 exception handling accesses env->pending_interrupts and
env->spr[SPR_LPCR] at multiple places. Passing it directly as local
variables simplifies the code and avoids multiple indirect accesses.
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Currently, p9 exception handling has multiple if-condition checks where
it does an indirect access to pending_interrupts and LPCR via env.
Pass the values during entry to avoid multiple indirect accesses.
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Add CPU target code to add support for new Power11 Processor.
Power11 core is same as Power10, hence reuse functions defined for
Power10.
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Aditya Gupta <adityag@linux.ibm.com>
Tested-by: Amit Machhiwal <amachhiw@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Doorbell exceptions are not not cleared when they cause a wake from
powersave state, only when they take the corresponding interrupt.
The sreset-on-wake logic must avoid clearing the interrupt in this
case.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
In Book-S / Power processors, the performance monitor interrupts are
driven by the MMCR0[PMAO] bit, which is level triggered and not cleared
by the interrupt.
Others may have different performance monitor architecture, but none of
those are implemented by QEMU.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Add helpers for TCG code to determine if there are SMT siblings
sharing per-core and per-lpar registers. This simplifies the
callers and makes SMT register topology simpler to modify with
later changes.
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
POWER8 (ISA v2.07S) introduced the doorbell facility, the msgsnd
instruction behaved mostly like msgsndp, it was addressed by TIR
and could only send interrupts between threads on the core.
ISA v3.0 changed msgsnd to be addressed by PIR and can interrupt
any thread in the system.
msgsnd only implements the v3.0 semantics, which can make
multi-threaded POWER8 hang when booting Linux (due to IPIs
failing). This change adds v2.07 semantics.
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
msgsnd has a broadcast mode that sends hypervisor doorbells to all
threads belonging to the same core as the target. A "subcore" mode
sends to all or one thread depending on 1LPAR mode.
Reviewed-by: Glenn Miles <milesg@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
attn is an implementation-specific instruction that on POWER (and G5/
970) can be enabled with a HID bit (disabled = illegal), and executing
it causes the host processor to stop and the service processor to be
notified. Generally used for debugging.
Implement attn and make it checkstop the system, which should be good
enough for QEMU debugging.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Change the logging not to print to stderr as well, because a
checkstop is a guest error (or perhaps a simulated machine error)
rather than a QEMU error, so send it to the log.
Update the checkstop message, and log CPU registers too.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Glenn Miles <milesg@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
checkstop state does not halt the system, interrupts continue to be
serviced, and other CPUs run. Make it stop the machine with
qemu_system_guest_panicked.
Reviewed-by: Glenn Miles <milesg@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Moving the following instructions to decodetree specification :
cmp{rb, eqb}, t{w, d} : X-form
t{w, d}i : D-form
isel : A-form
The changes were verified by validating that the tcg ops generated by those
instructions remain the same, which were captured using the '-d in_asm,op' flag.
Also for CMPRB, following review comments :
Replaced repetition of arithmetic right shifting (tcg_gen_shri_i32) followed
by extraction of last 8 bits (tcg_gen_ext8u_i32) with extraction of the required
bits using offsets (tcg_gen_extract_i32).
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Chinmay Rath <rathc@linux.ibm.com>
[np: 32-bit compile fix]
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
PPC_VIRTUAL_HYPERVISOR_GET_CLASS is used in critical operations like
interrupts and TLB misses and is quite costly. Running the
kvm-unit-tests sieve program with radix MMU enabled thrashes the TCG
TLB and spends a lot of time in TLB and page table walking code. The
test takes 67 seconds to complete with a lot of time being spent in
code related to finding the vhyp class:
12.01% [.] g_str_hash
8.94% [.] g_hash_table_lookup
8.06% [.] object_class_dynamic_cast
6.21% [.] address_space_ldq
4.94% [.] __strcmp_avx2
4.28% [.] tlb_set_page_full
4.08% [.] address_space_translate_internal
3.17% [.] object_class_dynamic_cast_assert
2.84% [.] ppc_radix64_xlate
Keep a pointer to the class and avoid this lookup. This reduces the
execution time to 40 seconds.
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
'abi_ptr' is a user specific type. The system emulation
equivalent is 'target_ulong'. Use it in ppc_ldl_code()
to emphasis this is not an user emulation function.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20231211212003.21686-18-philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Hardware clears the MSR[ME] bit when delivering a machine check
interrupt, so that is what QEMU does.
The spapr environment runs in supervisor mode though, and receives
machine check interrupts after they are processed by the hypervisor,
and MSR[ME] must always be enabled in supervisor mode (otherwise it
could checkstop the system). So MSR[ME] must not be cleared when
delivering machine checks to the supervisor.
The fix to prevent supervisor mode from modifying MSR[ME] also
prevented it from re-enabling the incorrectly cleared MSR[ME] bit
when returning from handling the interrupt. Before that fix, the
problem was not very noticable with well-behaved code. So the
Fixes tag is not strictly correct, but practically they go together.
Found by kvm-unit-tests machine check tests (not yet upstream).
Fixes: 678b6f1af75ef ("target/ppc: Prevent supervisor from modifying MSR[ME]")
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
These wrappers call out to handle POWER7 and newer in separate
functions but reduce to the generic case when TARGET_PPC64 is not
defined. It is easy enough to include the switch in the beginning of
the generic functions to branch out to the specific functions and get
rid of these wrappers. This avoids one indirection and entirely
compiles out the switch without TARGET_PPC64.
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Concatenate #if blocks that are ending then beginning on the next line
again.
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Remove check for !defined(CONFIG_USER_ONLY) as this is already within
an #ifndef CONFIG_USER_ONLY block.
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Use #ifdef, #ifndef for brevity and add comments to #endif that are
more than a few lines apart for clarity.
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Improve readability by shortening some long comments, removing
comments that state the obvious and dropping some empty lines so they
don't distract when reading the code.
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Use the env_cpu function to get the CPUState for cpu_abort. These are
only needed in case of fatal errors so this allows to avoid casting
and storing CPUState in a local variable wnen not needed.
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Mechanical patch produced running the command documented
in scripts/coccinelle/cpu_env.cocci_template header.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240129164514.73104-22-philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
is_prefix_insn_excp() loads the first word of the instruction address
which caused an exception, to determine whether or not it was prefixed
so the prefix bit can be set in [H]SRR1.
This works if the instruction image can be loaded, but if the exception
was caused by an ifetch, this load could fail and cause a recursive
exception and crash. Machine checks caused by ifetch are not excluded
from the prefix check and can crash (see issue 2108 for an example).
Fix this by excluding machine checks caused by ifetch from the prefix
check.
Cc: qemu-stable@nongnu.org
Acked-by: Cédric Le Goater <clg@kaod.org>
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2108
Fixes: 55a7fa34f89 ("target/ppc: Machine check on invalid real address access on POWER9/10")
Fixes: 5a5d3b23cb2 ("target/ppc: Add SRR1 prefix indication to interrupt handlers")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
The name "iothread" is overloaded. Use the term Big QEMU Lock (BQL)
instead, it is already widely used and unambiguous.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-id: 20240102153529.486531-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The Big QEMU Lock (BQL) has many names and they are confusing. The
actual QemuMutex variable is called qemu_global_mutex but it's commonly
referred to as the BQL in discussions and some code comments. The
locking APIs, however, are called qemu_mutex_lock_iothread() and
qemu_mutex_unlock_iothread().
The "iothread" name is historic and comes from when the main thread was
split into into KVM vcpu threads and the "iothread" (now called the main
loop thread). I have contributed to the confusion myself by introducing
a separate --object iothread, a separate concept unrelated to the BQL.
The "iothread" name is no longer appropriate for the BQL. Rename the
locking APIs to:
- void bql_lock(void)
- void bql_unlock(void)
- bool bql_locked(void)
There are more APIs with "iothread" in their names. Subsequent patches
will rename them. There are also comments and documentation that will be
updated in later patches.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Acked-by: Fabiano Rosas <farosas@suse.de>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Peter Xu <peterx@redhat.com>
Acked-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Acked-by: Hyman Huang <yong.huang@smartx.com>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-id: 20240102153529.486531-2-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When CPUArchState* is available (here CPUPPCState*), we
can use the fast env_archcpu() macro to get ArchCPU* (here
PowerPCCPU*). The QOM cast POWERPC_CPU() macro will be
slower when building with --enable-qom-cast-debug.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20231009110239.66778-2-philmd@linaro.org>
Convention is to reset the exception_index and error_code after handling
an interrupt. The vhyp hcall handler fails to do this. This does not
appear to have ill effects because cpu_handle_exception() clears
exception_index later, but it is fragile and inconsistent. Reset the
exception state after handling vhyp hcall like other handlers.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
ISA v2.07S introduced the watchpoint facility based on the DAWR0
and DAWRX0 SPRs. Implement this in TCG.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
ISA v2.07S introduced the breakpoint facility based on the CIABR SPR.
Implement this in TCG.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Improve the emulation accuracy of the single step and branch trace
interrupts for v2.07S. Set SRR1[33]=1, and set SIAR to completed
instruction address.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
