[PATCH v3 20/33] net/ena/hal: check for existing keep alive notification

[shaibran]

From: Shai Brandes <shaib...@amazon.com>

This commit adds an API to query the aenq on whether
there is a pending keep alive notification.

Signed-off-by: Shai Brandes <shaib...@amazon.com>
Reviewed-by: Amit Bernstein <amitb...@amazon.com>
---
 drivers/net/ena/hal/ena_com.c | 39 +++++++++++++++++++++++++++++++++++
 drivers/net/ena/hal/ena_com.h | 10 +++++++++
 2 files changed, 49 insertions(+)

diff --git a/drivers/net/ena/hal/ena_com.c b/drivers/net/ena/hal/ena_com.c
index 8e9c112715..f9613f7807 100644
--- a/drivers/net/ena/hal/ena_com.c
+++ b/drivers/net/ena/hal/ena_com.c
@@ -2456,6 +2456,45 @@ void ena_com_aenq_intr_handler(struct ena_com_dev 
*ena_dev, void *data)
        mmiowb();
 }
 
+bool ena_com_aenq_has_keep_alive(struct ena_com_dev *ena_dev)
+{
+       struct ena_admin_aenq_common_desc *aenq_common;
+       struct ena_com_aenq *aenq = &ena_dev->aenq;
+       struct ena_admin_aenq_entry *aenq_e;
+       u8 phase = aenq->phase;
+       u16 masked_head;
+
+       masked_head = aenq->head & (aenq->q_depth - 1);
+       aenq_e = &aenq->entries[masked_head]; /* Get first entry */
+       aenq_common = &aenq_e->aenq_common_desc;
+
+       /* Go over all the events */
+       while ((READ_ONCE8(aenq_common->flags) &
+               ENA_ADMIN_AENQ_COMMON_DESC_PHASE_MASK) == phase) {
+               /* Make sure the device finished writing the rest of the 
descriptor
+                * before reading it.
+                */
+               dma_rmb();
+
+               if (aenq_common->group == ENA_ADMIN_KEEP_ALIVE)
+                       return true;
+
+               /* Get next event entry */
+               masked_head++;
+
+               if (unlikely(masked_head == aenq->q_depth)) {
+                       masked_head = 0;
+                       phase = !phase;
+               }
+
+               aenq_e = &aenq->entries[masked_head];
+               aenq_common = &aenq_e->aenq_common_desc;
+       }
+
+       return false;
+}
+
+
 int ena_com_dev_reset(struct ena_com_dev *ena_dev,
                      enum ena_regs_reset_reason_types reset_reason)
 {
diff --git a/drivers/net/ena/hal/ena_com.h b/drivers/net/ena/hal/ena_com.h
index c999cd2381..737747f64b 100644
--- a/drivers/net/ena/hal/ena_com.h
+++ b/drivers/net/ena/hal/ena_com.h
@@ -639,6 +639,16 @@ void ena_com_admin_q_comp_intr_handler(struct ena_com_dev 
*ena_dev);
  */
 void ena_com_aenq_intr_handler(struct ena_com_dev *ena_dev, void *data);
 
+/* ena_com_aenq_has_keep_alive - Retrieve if there is a keep alive 
notification in the aenq
+ * @ena_dev: ENA communication layer struct
+ *
+ * This method goes over the async event notification queue and returns if 
there
+ * is a keep alive notification.
+ *
+ * @return - true if there is a keep alive notification in the aenq or false 
otherwise
+ */
+bool ena_com_aenq_has_keep_alive(struct ena_com_dev *ena_dev);
+
 /* ena_com_abort_admin_commands - Abort all the outstanding admin commands.
  * @ena_dev: ENA communication layer struct
  *
-- 
2.17.1