qcacld-2.0: fix corruption of irq history buffer index

There is a race condition between irq history type
HIF_SUSPEND_AFTER_WOW and HIF_IRQ, this is corrupting
the irq history buffer index.
Fix the race condition by using atomic index counter.

Change-Id: I61e42d28a9eb242e13cc73cdab8efb52e1574cb6
CRs-Fixed: 1039967

3 files changed, 16 insertions, 14 deletions

diff --git a/CORE/SERVICES/HIF/PCIe/copy_engine.c b/CORE/SERVICES/HIF/PCIe/copy_engine.c
index 1ec4cae236f6..9619e93d07f3 100644
--- a/CORE/SERVICES/HIF/PCIe/copy_engine.c
+++ b/CORE/SERVICES/HIF/PCIe/copy_engine.c
@@ -104,7 +104,7 @@ static void CE_init_ce_desc_event_log(int ce_id, int size);
  * trying to access the array, full locking of the recording process would
  * be needed to have sane logging.
  */
-static int get_next_record_index(adf_os_atomic_t *table_index, int array_size)
+int get_next_record_index(adf_os_atomic_t *table_index, int array_size)
 {
 	int record_index = adf_os_atomic_inc_return(table_index);
 	if (record_index == array_size)
diff --git a/CORE/SERVICES/HIF/PCIe/copy_engine_api.h b/CORE/SERVICES/HIF/PCIe/copy_engine_api.h
index 7e03a5f28574..d69641540ab1 100644
--- a/CORE/SERVICES/HIF/PCIe/copy_engine_api.h
+++ b/CORE/SERVICES/HIF/PCIe/copy_engine_api.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2014 The Linux Foundation. All rights reserved.
+ * Copyright (c) 2013-2014, 2016 The Linux Foundation. All rights reserved.
  *
  * Previously licensed under the ISC license by Qualcomm Atheros, Inc.
  *
@@ -374,6 +374,9 @@ void CE_enable_any_copy_compl_intr_nolock(struct hif_pci_softc *sc);
 /* API to check if any of the copy engine pipes has pending frames for prcoessing */
 bool CE_get_rx_pending(struct hif_pci_softc *sc);
 
+int get_next_record_index(atomic_t *table_index, int array_size);
+
+
 /* CE_attr.flags values */
 #define CE_ATTR_NO_SNOOP                0x01  /* Use NonSnooping PCIe accesses? */
 #define CE_ATTR_BYTE_SWAP_DATA          0x02  /* Byte swap data words */
diff --git a/CORE/SERVICES/HIF/PCIe/if_pci.c b/CORE/SERVICES/HIF/PCIe/if_pci.c
index af339871abad..0e8edec7b286 100644
--- a/CORE/SERVICES/HIF/PCIe/if_pci.c
+++ b/CORE/SERVICES/HIF/PCIe/if_pci.c
@@ -154,7 +154,7 @@ typedef struct {
 } hif_irq_history;
 
 #define HIF_IRQ_HISTORY_MAX 1024
-A_UINT32 g_hif_irq_history_idx = 0;
+adf_os_atomic_t g_hif_irq_history_idx = 0;
 hif_irq_history hif_irq_history_buffer[HIF_IRQ_HISTORY_MAX];
 
 void hif_irq_record(hif_irq_type type, struct hif_pci_softc *sc)
@@ -162,36 +162,35 @@ void hif_irq_record(hif_irq_type type, struct hif_pci_softc *sc)
 	struct HIF_CE_state *hif_state = (struct HIF_CE_state *)sc->hif_device;
 	A_target_id_t targid = hif_state->targid;
 
-	if (HIF_IRQ_HISTORY_MAX <= g_hif_irq_history_idx)
-		g_hif_irq_history_idx = 0;
+	int record_index = get_next_record_index(
+			&g_hif_irq_history_idx, HIF_IRQ_HISTORY_MAX);
 
 	if (HIFTargetSleepStateAdjust(hif_state->targid, FALSE, TRUE) < 0) {
-		adf_os_mem_zero(&hif_irq_history_buffer[g_hif_irq_history_idx],
+		adf_os_mem_zero(&hif_irq_history_buffer[record_index],
 				sizeof(hif_irq_history));
 		goto out;
 	}
 
-	hif_irq_history_buffer[g_hif_irq_history_idx].irq_summary =
+	hif_irq_history_buffer[record_index].irq_summary =
 			CE_INTERRUPT_SUMMARY(targid);
-	hif_irq_history_buffer[g_hif_irq_history_idx].fw_indicator =
+	hif_irq_history_buffer[record_index].fw_indicator =
 			A_TARGET_READ(targid, hif_state->fw_indicator_address);
-	hif_irq_history_buffer[g_hif_irq_history_idx].irq_enable =
+	hif_irq_history_buffer[record_index].irq_enable =
 			A_PCI_READ32(sc->mem + SOC_CORE_BASE_ADDRESS +
 				PCIE_INTR_ENABLE_ADDRESS);
-	hif_irq_history_buffer[g_hif_irq_history_idx].irq_cause =
+	hif_irq_history_buffer[record_index].irq_cause =
 			A_PCI_READ32(sc->mem + SOC_CORE_BASE_ADDRESS +
 				PCIE_INTR_CAUSE_ADDRESS);
-	hif_irq_history_buffer[g_hif_irq_history_idx].irq_clear =
+	hif_irq_history_buffer[record_index].irq_clear =
 			A_PCI_READ32(sc->mem + SOC_CORE_BASE_ADDRESS +
 				PCIE_INTR_CLR_ADDRESS);
 
 	HIFTargetSleepStateAdjust(hif_state->targid, TRUE, FALSE);
 
 out:
-	hif_irq_history_buffer[g_hif_irq_history_idx].type = type;
-	hif_irq_history_buffer[g_hif_irq_history_idx].time = adf_get_boottime();
+	hif_irq_history_buffer[record_index].type = type;
+	hif_irq_history_buffer[record_index].time = adf_get_boottime();
 
-	g_hif_irq_history_idx++;
 }
 #else
 void hif_irq_record(hif_irq_type type, struct hif_pci_softc *sc) {};