qcacmn: In SAP-WOW-D0 state, wake-up FW on receiption of unicast pkt

When unit test command "iwpriv wlan0 wlan_suspend 0 0" is issued on
SAP-DUT (given that one REF-STA is connected), FW would go in WOW-D0
state. In this state, when HW receives the pkt from peer (REF-STA), it
generates MSI (REO-interrupt) and host process this pkt but it doesn't
wake-up the FW. Due to this situation, no TX is happening on SAP after
issueing wlan_suspend command.

This situation only happens when iwpriv command issued as this command
would be fool the FW by notifying that APSS is in power-down state but
actually it is not in active state. When APSS is really in power-down
state then up-on receiption of any RX pkt would wake-up the APSS and
this waking-up process would wake-up FW as well.

Fix this situation by sending explicit FW wake-up event.

CRs-Fixed: 2325860
Change-Id: I18937e5c568c742f838cdf3f815c2184a916283c

hif/src/hif_exec.c

@@ -316,6 +316,32 @@ uint32_t hif_configure_ext_group_interrupts(struct hif_opaque_softc *hif_ctx)
 }
 qdf_export_symbol(hif_configure_ext_group_interrupts);
 
+#ifdef WLAN_SUSPEND_RESUME_TEST
+/**
+ * hif_check_and_trigger_ut_resume() - check if unit-test command was used to
+ *				       to trigger fake-suspend command, if yes
+ *				       then issue resume procedure.
+ * @scn: opaque HIF software context
+ *
+ * This API checks if unit-test command was used to trigger fake-suspend command
+ * and if answer is yes then it would trigger resume procedure.
+ *
+ * Make this API inline to save API-switch overhead and do branch-prediction to
+ * optimize performance impact.
+ *
+ * Return: void
+ */
+static inline void hif_check_and_trigger_ut_resume(struct hif_softc *scn)
+{
+	if (qdf_unlikely(hif_irq_trigger_ut_resume(scn)))
+		hif_ut_fw_resume(scn);
+}
+#else
+static inline void hif_check_and_trigger_ut_resume(struct hif_softc *scn)
+{
+}
+#endif
+
 /**
  * hif_ext_group_interrupt_handler() - handler for related interrupts
  * @irq: irq number of the interrupt
@@ -332,6 +358,19 @@ irqreturn_t hif_ext_group_interrupt_handler(int irq, void *context)
 
 	if (hif_ext_group->irq_requested) {
 		hif_ext_group->irq_disable(hif_ext_group);
+		/*
+		 * if private ioctl has issued fake suspend command to put
+		 * FW in D0-WOW state then here is our chance to bring FW out
+		 * of WOW mode.
+		 *
+		 * The reason why you need to explicitly wake-up the FW is here:
+		 * APSS should have been in fully awake through-out when
+		 * fake APSS suspend command was issued (to put FW in WOW mode)
+		 * hence organic way of waking-up the FW
+		 * (as part-of APSS-host wake-up) won't happen because
+		 * in reality APSS didn't really suspend.
+		 */
+		hif_check_and_trigger_ut_resume(scn);
 		qdf_atomic_inc(&scn->active_grp_tasklet_cnt);
 
 		hif_ext_group->sched_ops->schedule(hif_ext_group);

hif/src/hif_unit_test_suspend.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017 The Linux Foundation. All rights reserved.
+ * Copyright (c) 2017-2018 The Linux Foundation. All rights reserved.
  *
  * Permission to use, copy, modify, and/or distribute this software for
  * any purpose with or without fee is hereby granted, provided that the
@@ -112,3 +112,11 @@ QDF_STATUS hif_ut_fw_resume(struct hif_softc *scn)
 
 	return QDF_STATUS_SUCCESS;
 }
+
+bool hif_irq_trigger_ut_resume(struct hif_softc *scn)
+{
+	if (!hif_is_ut_suspended(scn))
+		return false;
+
+	return true;
+}

hif/src/hif_unit_test_suspend_i.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017 The Linux Foundation. All rights reserved.
+ * Copyright (c) 2017-2018 The Linux Foundation. All rights reserved.
  *
  * Permission to use, copy, modify, and/or distribute this software for
  * any purpose with or without fee is hereby granted, provided that the
@@ -63,6 +63,14 @@ bool hif_is_ut_suspended(struct hif_softc *scn);
  */
 QDF_STATUS hif_ut_fw_resume(struct hif_softc *scn);
 
+/**
+ * hif_irq_trigger_ut_resume() - Test for given hif ctx unit-test resume needed
+ * @scn: The HIF context to check
+ *
+ * Return: true, if unit-test resume procedure is needed, otherwise false
+ */
+bool hif_irq_trigger_ut_resume(struct hif_softc *scn);
+
 #else /* WLAN_SUSPEND_RESUME_TEST */
 
 struct hif_ut_suspend_context {};
@@ -78,7 +86,6 @@ static inline QDF_STATUS hif_ut_fw_resume(struct hif_softc *scn)
 {
 	return QDF_STATUS_SUCCESS;
 }
-
 #endif /* WLAN_SUSPEND_RESUME_TEST */
 
 #endif /* _HIF_UNIT_TEST_SUSPEND_I_H_ */