qcacld-3.0: Call icnss API to check if WLAN FW is down

If modem crashed during wlan driver unloading, icnss driver
will call driver uevent callback to set FW down status in
driver side when it receives BEFORE_SHUTDOWN notification.
If wlan driver is de-initialized just before the callback
is called, kernel will panic as driver's context is freed.
This can be avoid by not setting FW status in host driver.
Instead, icnss driver provides an API to host driver to
check FW status and host driver calls this API before any timeout
assert or accessing HW registers.

CRs-Fixed: 2161431
Change-Id: I8331367dd41dd0cedfa65c63f1bb3ffcb535e1c9

core/cds/inc/cds_api.h

@@ -77,11 +77,9 @@ enum cds_driver_state {
 /**
  * enum cds_fw_state - Firmware state
  * @CDS_FW_STATE_UNINITIALIZED: Firmware is in uninitialized state.
- * CDS_FW_STATE_DOWN: Firmware is down.
  */
 enum cds_fw_state {
 	CDS_FW_STATE_UNINITIALIZED = 0,
-	CDS_FW_STATE_DOWN,
 };
 
 #define __CDS_IS_FW_STATE(_state, _mask) (((_state) & (_mask)) == (_mask))
@@ -207,32 +205,6 @@ static inline bool cds_is_module_stop_in_progress(void)
 	return __CDS_IS_DRIVER_STATE(state, CDS_DRIVER_STATE_MODULE_STOPPING);
 }
 
-/**
- * cds_is_fw_down() - Is FW down or not
- *
- * Return: true if FW is down and false otherwise.
- */
-static inline bool cds_is_fw_down(void)
-{
-	enum cds_fw_state state = cds_get_fw_state();
-
-	return __CDS_IS_FW_STATE(state, BIT(CDS_FW_STATE_DOWN));
-}
-
-/**
- * cds_set_fw_down() - Set or unset FW down bit
- * @value: value to set
- *
- * Return: none
- */
-static inline void cds_set_fw_down(uint8_t value)
-{
-	if (value)
-		cds_set_fw_state(CDS_FW_STATE_DOWN);
-	else
-		cds_clear_fw_state(CDS_FW_STATE_DOWN);
-}
-
 /**
  * cds_is_target_ready() - Is target is in ready state
  *
@@ -532,6 +504,7 @@ bool cds_is_5_mhz_enabled(void);
 bool cds_is_10_mhz_enabled(void);
 bool cds_is_sub_20_mhz_enabled(void);
 bool cds_is_self_recovery_enabled(void);
+bool cds_is_fw_down(void);
 enum QDF_GLOBAL_MODE cds_get_conparam(void);
 
 #ifdef WLAN_LOGGING_SOCK_SVC_ENABLE

core/cds/src/cds_api.c

@@ -2615,6 +2615,19 @@ bool cds_is_self_recovery_enabled(void)
 	return false;
 }
 
+/**
+ * cds_is_fw_down() - Is FW down or not
+ *
+ * Return: true if FW is down and false otherwise.
+ */
+bool cds_is_fw_down(void)
+{
+	qdf_device_t qdf_ctx;
+
+	qdf_ctx = cds_get_context(QDF_MODULE_ID_QDF_DEVICE);
+	return pld_is_fw_down(qdf_ctx->dev);
+}
+
 /**
  * cds_svc_fw_shutdown_ind() - API to send userspace about FW crash
  *

core/hdd/src/wlan_hdd_driver_ops.c

@@ -390,7 +390,6 @@ static int hdd_soc_probe(struct device *dev,
 
 	probe_fail_cnt = 0;
 	cds_set_driver_loaded(true);
-	cds_set_fw_down(false);
 	hdd_start_complete(0);
 	cds_set_load_in_progress(false);
 
@@ -403,7 +402,6 @@ assert_fail_count:
 	QDF_BUG(probe_fail_cnt < SSR_MAX_FAIL_CNT);
 
 unlock:
-	cds_set_fw_down(false);
 	cds_set_load_in_progress(false);
 	hdd_soc_load_unlock(dev);
 
@@ -433,7 +431,6 @@ static int hdd_soc_reinit(struct device *dev, void *bdev,
 	}
 
 	re_init_fail_cnt = 0;
-	cds_set_fw_down(false);
 	cds_set_recovery_in_progress(false);
 
 	hdd_soc_load_unlock(dev);
@@ -447,7 +444,6 @@ assert_fail_count:
 unlock:
 	cds_set_driver_in_bad_state(true);
 	cds_set_recovery_in_progress(false);
-	cds_set_fw_down(false);
 	hdd_soc_load_unlock(dev);
 
 	return check_for_probe_defer(errno);
@@ -1497,7 +1493,6 @@ static void wlan_hdd_set_the_pld_uevent(struct pld_uevent_data *uevent)
 		cds_set_recovery_in_progress(true);
 		break;
 	case PLD_FW_DOWN:
-		cds_set_fw_state(CDS_FW_STATE_DOWN);
 		cds_set_target_ready(false);
 		cds_set_recovery_in_progress(true);
 		break;

core/pld/inc/pld_common.h

@@ -542,6 +542,7 @@ void pld_get_msi_address(struct device *dev, uint32_t *msi_addr_low,
 			 uint32_t *msi_addr_high);
 unsigned int pld_socinfo_get_serial_number(struct device *dev);
 int pld_is_qmi_disable(struct device *dev);
+int pld_is_fw_down(struct device *dev);
 int pld_force_assert_target(struct device *dev);
 bool pld_is_fw_dump_skipped(struct device *dev);
 

core/pld/src/pld_common.c

@@ -1473,6 +1473,35 @@ int pld_is_qmi_disable(struct device *dev)
 	return ret;
 }
 
+/**
+ * pld_is_fw_down() - Check WLAN fw is down or not
+ *
+ * @dev: device
+ *
+ * This API will be called to check if WLAN FW is down or not.
+ *
+ *  Return: 1 FW is down
+ *          0 FW is not down
+ *          Non zero failure code for errors
+ */
+int pld_is_fw_down(struct device *dev)
+{
+	int ret = 0;
+	enum pld_bus_type type = pld_get_bus_type(dev);
+
+	switch (type) {
+	case PLD_BUS_TYPE_SNOC:
+		ret = pld_snoc_is_fw_down(dev);
+		break;
+	default:
+		pr_err("Invalid device type %d\n", type);
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
 /**
  * pld_force_assert_target() - Send a force assert to FW.
  * This can use various sideband requests available at platform to

core/pld/src/pld_snoc.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016-2017 The Linux Foundation. All rights reserved.
+ * Copyright (c) 2016-2018 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
@@ -113,6 +113,11 @@ static inline int pld_snoc_is_qmi_disable(struct device *dev)
 {
 	return 0;
 }
+
+static inline int pld_snoc_is_fw_down(struct device *dev)
+{
+	return 0;
+}
 static inline int pld_snoc_set_fw_log_mode(struct device *dev, u8 fw_log_mode)
 {
 	return 0;
@@ -251,6 +256,11 @@ unsigned int pld_snoc_socinfo_get_serial_number(struct device *dev)
 	return icnss_socinfo_get_serial_number(dev);
 }
 
+static inline int pld_snoc_is_fw_down(struct device *dev)
+{
+	return icnss_is_fw_down();
+}
+
 #ifdef ICNSS_API_WITH_DEV
 static inline int pld_snoc_is_qmi_disable(struct device *dev)
 {