On 23/3/25 23:49, BALATON Zoltan wrote:
On Sun, 23 Mar 2025, Richard Henderson wrote:
On 3/23/25 15:13, BALATON Zoltan wrote:
On Sun, 23 Mar 2025, Philippe Mathieu-Daudé wrote:
On 23/3/25 20:07, Richard Henderson wrote:
diff --git a/target/ppc/cpu_init.c b/target/ppc/cpu_init.c
index 28fbbb8d3c1..ed79cc1a6b7 100644
--- a/target/ppc/cpu_init.c
+++ b/target/ppc/cpu_init.c
@@ -7490,6 +7490,7 @@ static const TCGCPUOps ppc_tcg_ops = {
.translate_code = ppc_translate_code,
.restore_state_to_opc = ppc_restore_state_to_opc,
+ .mttcg_supported = TARGET_LONG_BITS == 64,
.guest_default_memory_order = 0,
Similarly. I'd be surprised if ppc32 can't use mttcg, really.
Per Cédric on IRC our ppc32 implementations are single core,
so never tested for mttcg.
We're just trying to implement more CPUs for G4 mac99 and tested it
with -smp 2 and it seems to generally work but we need to implement
more of the Mac hardware for this but we could already run Mac OS X
with two CPUs and mttcg and Linux too if we add a delay on boot when
second CPU is started (it may need implementing timebase control as
done on the G4 Mac to avoid that but if it gets past that it seems to
work). So please leave this enabled. Not tested does not mean it does
not work so only disable if there's a known problem.
MTTCG is not enabled for qemu-system-ppc right now.
I could use -smp 2 with qemu-system-ppc after this:
https://lists.nongnu.org/archive/html/qemu-ppc/2025-02/msg00377.html
It complains about not tested for the board but works nevertheless. I
don't remember if I've enabled mttcg or not so maybe it only ran with
single thread which was enough for testing but others did test mttcg:
https://lists.nongnu.org/archive/html/qemu-ppc/2025-02/msg00455.html
although could be that with qemu-system-ppc64 which also includes 32 bit
machines. But then it should work the same with qemu-system-ppc so it
could be enabled there as well.
Phil's patch does not current change behaviour.
Then what does the line do at all? In any case we may want to enable
mttcg in qemu-system-ppc in the future so maybe there's no need to
restrict it here.
In the future you can enable it posting this patch:
-- >8 --
diff --git a/target/ppc/cpu_init.c b/target/ppc/cpu_init.c
@@ -7492,6 +7492,7 @@ static const TCGCPUOps ppc_tcg_ops = {
- .mttcg_supported = TARGET_LONG_BITS == 64,
+ .mttcg_supported = true,
---
which is equivalent of today's:
-- >8 --
diff --git a/configs/targets/ppc-softmmu.mak
b/configs/targets/ppc-softmmu.mak
@@ -5 +5,2 @@ TARGET_XML_FILES= gdb-xml/power-core.xml
gdb-xml/power-fpu.xml gdb-xml/power-alt
TARGET_LONG_BITS=32
+TARGET_SUPPORTS_MTTCG=y
---
I'll let you write the commit description.
Regards,
Phil.
