The PQ state of a xive interrupt is always initialized to Q=1, which
means the interrupt is disabled. Since a xive source can be embedded
in many objects, this patch adds a property to allow that behavior to
be refined if needed.

Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
---
 hw/intc/xive.c        | 8 ++++++--
 include/hw/ppc/xive.h | 1 +
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/hw/intc/xive.c b/hw/intc/xive.c
index 84c079b034..c553b32638 100644
--- a/hw/intc/xive.c
+++ b/hw/intc/xive.c
@@ -1232,8 +1232,7 @@ static void xive_source_reset(void *dev)
 
     /* Do not clear the LSI bitmap */
 
-    /* PQs are initialized to 0b01 (Q=1) which corresponds to "ints off" */
-    memset(xsrc->status, XIVE_ESB_OFF, xsrc->nr_irqs);
+    memset(xsrc->status, xsrc->pq_init, xsrc->nr_irqs);
 }
 
 static void xive_source_realize(DeviceState *dev, Error **errp)
@@ -1287,6 +1286,11 @@ static Property xive_source_properties[] = {
     DEFINE_PROP_UINT64("flags", XiveSource, esb_flags, 0),
     DEFINE_PROP_UINT32("nr-irqs", XiveSource, nr_irqs, 0),
     DEFINE_PROP_UINT32("shift", XiveSource, esb_shift, XIVE_ESB_64K_2PAGE),
+    /*
+     * By default, PQs are initialized to 0b01 (Q=1) which corresponds
+     * to "ints off"
+     */
+    DEFINE_PROP_UINT8("pq-init", XiveSource, pq_init, XIVE_ESB_OFF),
     DEFINE_PROP_LINK("xive", XiveSource, xive, TYPE_XIVE_NOTIFIER,
                      XiveNotifier *),
     DEFINE_PROP_END_OF_LIST(),
diff --git a/include/hw/ppc/xive.h b/include/hw/ppc/xive.h
index 3dfb06e002..7969f06bcf 100644
--- a/include/hw/ppc/xive.h
+++ b/include/hw/ppc/xive.h
@@ -187,6 +187,7 @@ struct XiveSource {
 
     /* PQ bits and LSI assertion bit */
     uint8_t         *status;
+    uint8_t         pq_init; /* PQ state on reset */
 
     /* ESB memory region */
     uint64_t        esb_flags;
-- 
2.41.0

On 6/30/23 16:42, Frederic Barrat wrote:
> The PQ state of a xive interrupt is always initialized to Q=1, which
> means the interrupt is disabled. Since a xive source can be embedded
> in many objects, this patch adds a property to allow that behavior to
> be refined if needed.
> 
> Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>

Looks good but I would rather call the property "reset-pq" and the
attribute reset_pq. Makes more sense since it is a "reset" value.

Thanks,

C.


> ---
>   hw/intc/xive.c        | 8 ++++++--
>   include/hw/ppc/xive.h | 1 +
>   2 files changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/intc/xive.c b/hw/intc/xive.c
> index 84c079b034..c553b32638 100644
> --- a/hw/intc/xive.c
> +++ b/hw/intc/xive.c
> @@ -1232,8 +1232,7 @@ static void xive_source_reset(void *dev)
>   
>       /* Do not clear the LSI bitmap */
>   
> -    /* PQs are initialized to 0b01 (Q=1) which corresponds to "ints off" */
> -    memset(xsrc->status, XIVE_ESB_OFF, xsrc->nr_irqs);
> +    memset(xsrc->status, xsrc->pq_init, xsrc->nr_irqs);
>   }
>   
>   static void xive_source_realize(DeviceState *dev, Error **errp)
> @@ -1287,6 +1286,11 @@ static Property xive_source_properties[] = {
>       DEFINE_PROP_UINT64("flags", XiveSource, esb_flags, 0),
>       DEFINE_PROP_UINT32("nr-irqs", XiveSource, nr_irqs, 0),
>       DEFINE_PROP_UINT32("shift", XiveSource, esb_shift, XIVE_ESB_64K_2PAGE),
> +    /*
> +     * By default, PQs are initialized to 0b01 (Q=1) which corresponds
> +     * to "ints off"
> +     */
> +    DEFINE_PROP_UINT8("pq-init", XiveSource, pq_init, XIVE_ESB_OFF),
>       DEFINE_PROP_LINK("xive", XiveSource, xive, TYPE_XIVE_NOTIFIER,
>                        XiveNotifier *),
>       DEFINE_PROP_END_OF_LIST(),
> diff --git a/include/hw/ppc/xive.h b/include/hw/ppc/xive.h
> index 3dfb06e002..7969f06bcf 100644
> --- a/include/hw/ppc/xive.h
> +++ b/include/hw/ppc/xive.h
> @@ -187,6 +187,7 @@ struct XiveSource {
>   
>       /* PQ bits and LSI assertion bit */
>       uint8_t         *status;
> +    uint8_t         pq_init; /* PQ state on reset */
>   
>       /* ESB memory region */
>       uint64_t        esb_flags;