lib: sbi: sse: allow adding new events

In order to allow events to be dynamically added, remove the existing
static array of events and use a simply linked list of supported events.
This allows us to move the cb_ops into this list and associated it with
an event_id. Drivers can now register cb_ops before bringing up the sse
core to handle additional events (platform ones for instance).

sbi_sse_init() now allocates as many events as present in the linked
list. Events can now be added with sbi_sse_add_event() which allows to
add new supported events with some callback operations if any. If an
event is not to be supported, then sbi_sse_add_event() should not be
called. This approach currently consider that local events are to be
supported on all harts (ie, they all support the same ISA or
dependencies). If per-hart event availability needs to be supported,
then, an is_supported() callback could be added later and called for
each hart.

Signed-off-by: Clément Léger <[email protected]>
Reviewed-by: Samuel Holland <[email protected]>

1 files changed, 4 insertions, 4 deletions

diff --git a/include/sbi/sbi_sse.h b/include/sbi/sbi_sse.h
index 7419698a..fb796545 100644
--- a/include/sbi/sbi_sse.h
+++ b/include/sbi/sbi_sse.h
@@ -54,12 +54,12 @@ struct sbi_sse_cb_ops {
 	void (*disable_cb)(uint32_t event_id);
 };
 
-/* Set the callback operations for an event
- * @param event_id Event identifier (SBI_SSE_EVENT_*)
- * @param cb_ops Callback operations
+/* Add a supported event with associated callback operations
+ * @param event_id Event identifier (SBI_SSE_EVENT_* or a custom platform one)
+ * @param cb_ops Callback operations (Can be NULL if any)
  * @return 0 on success, error otherwise
  */
-int sbi_sse_set_cb_ops(uint32_t event_id, const struct sbi_sse_cb_ops *cb_ops);
+int sbi_sse_add_event(uint32_t event_id, const struct sbi_sse_cb_ops *cb_ops);
 
 /* Inject an event to the current hard
  * @param event_id Event identifier (SBI_SSE_EVENT_*)