Hi Philippe Mathieu-Daudé :
Hi,
On 12/9/23 04:11, xianglai li wrote:
It will be reused in loongarch/virt.c for unwiring
the vcpu<->exioi interrupts for the vcpu hot-(un)plug
cases.
Since we never had to use this, I'm surprised we really need it.
QEMU IRQs/GPIOs are similar to hardware ones, and aren't expected
to be rewired at runtime. Usually another hot-pluggable bus layer is
used, and the bus is physically wired toward the hardware.
I suppose you want to add that because a unplugged vCPU is still
receiving IRQs. The question is, why? Before unplugging, I expect
the INTC (IPI) here to be signaled a vCPU is going to be unplugged,
so maybe you are missing handling the unplug event there. See
I did not receive an interrupt signal after pulling out the vcpu.
Whether to use the qdev_disconnect_gpio_out_named function does not
affect the cpu hot swap function.
The qdev_disconnect_gpio_out_named function is used only to make
loongarch_cpu_irq_init and loongarch_cpu_irq_uninit symmetrical.
I thought it would make the whole process more regular and nice.
If this causes confusion I think with the next patch I can remove the
reference to this function.
Thanks,
xianglai.
in loongarch_ipi_writel():
switch (addr) {
case CORE_EN_OFF:
s->en = val;
break;
case CORE_SET_OFF:
s->status |= val;
if (s->status != 0 && (s->status & s->en) != 0) {
qemu_irq_raise(s->irq);
}
break;
case CORE_CLEAR_OFF:
s->status &= ~val;
if (s->status == 0 && s->en != 0) {
qemu_irq_lower(s->irq);
}
break;
Maybe you need to factor ipi_raise/lower() helpers which check cores
are available & enabled before propagating IRQ?
Co-authored-by: "Salil Mehta" <salil.me...@opnsrc.net>
Cc: "Salil Mehta" <salil.me...@opnsrc.net>
Cc: Xiaojuan Yang <yangxiaoj...@loongson.cn>
Cc: Song Gao <gaos...@loongson.cn>
Cc: "Michael S. Tsirkin" <m...@redhat.com>
Cc: Igor Mammedov <imamm...@redhat.com>
Cc: Ani Sinha <anisi...@redhat.com>
Cc: Paolo Bonzini <pbonz...@redhat.com>
Cc: Richard Henderson <richard.hender...@linaro.org>
Cc: Eduardo Habkost <edua...@habkost.net>
Cc: Marcel Apfelbaum <marcel.apfelb...@gmail.com>
Cc: "Philippe Mathieu-Daudé" <phi...@linaro.org>
Cc: Yanan Wang <wangyana...@huawei.com>
Cc: "Daniel P. Berrangé" <berra...@redhat.com>
Cc: Peter Xu <pet...@redhat.com>
Cc: David Hildenbrand <da...@redhat.com>
Cc: Bibo Mao <maob...@loongson.cn>
Signed-off-by: xianglai li <lixiang...@loongson.cn>
---
hw/core/gpio.c | 4 ++--
include/hw/qdev-core.h | 2 ++
2 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/hw/core/gpio.c b/hw/core/gpio.c
index 80d07a6ec9..4fc6409545 100644
--- a/hw/core/gpio.c
+++ b/hw/core/gpio.c
@@ -143,8 +143,8 @@ qemu_irq qdev_get_gpio_out_connector(DeviceState
*dev, const char *name, int n)
/* disconnect a GPIO output, returning the disconnected input (if
any) */
-static qemu_irq qdev_disconnect_gpio_out_named(DeviceState *dev,
- const char *name, int n)
+qemu_irq qdev_disconnect_gpio_out_named(DeviceState *dev,
+ const char *name, int n)
{
char *propname = g_strdup_printf("%s[%d]",
name ? name :
"unnamed-gpio-out", n);
diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h
index 151d968238..32bb54163e 100644
--- a/include/hw/qdev-core.h
+++ b/include/hw/qdev-core.h
@@ -739,6 +739,8 @@ qemu_irq qdev_get_gpio_out_connector(DeviceState
*dev, const char *name, int n);
*/
qemu_irq qdev_intercept_gpio_out(DeviceState *dev, qemu_irq icpt,
const char *name, int n);
+qemu_irq qdev_disconnect_gpio_out_named(DeviceState *dev,
+ const char *name, int n);
BusState *qdev_get_child_bus(DeviceState *dev, const char *name);
