Merge branch 'pci/endpoint'

- Convert dra7xx to threaded IRQ handler (Manivannan Sadhasivam)

- Move tegra194 dw_pcie_ep_linkup() to threaded IRQ handler (Manivannan
  Sadhasivam)

- Add a separate lock for the endpoint pci_epf list to avoid deadlock
  while running callbacks (Manivannan Sadhasivam)

- Use callbacks instead of notifier chains to signal events from EPC to EPF
  drivers (Manivannan Sadhasivam)

- Use link_up() callback in place of LINK_UP notifier (Manivannan
  Sadhasivam)

* pci/endpoint:
  PCI: endpoint: Use link_up() callback in place of LINK_UP notifier
  PCI: endpoint: Use callback mechanism for passing events from EPC to EPF
  PCI: endpoint: Use a separate lock for protecting epc->pci_epf list
  PCI: tegra194: Move dw_pcie_ep_linkup() to threaded IRQ handler
  PCI: dra7xx: Use threaded IRQ handler for "dra7xx-pcie-main" IRQ

6 files changed, 59 insertions, 51 deletions

diff --git a/drivers/pci/controller/dwc/pci-dra7xx.c b/drivers/pci/controller/dwc/pci-dra7xx.c
index 38462ed11d07..4ae807e7cf79 100644
--- a/drivers/pci/controller/dwc/pci-dra7xx.c
+++ b/drivers/pci/controller/dwc/pci-dra7xx.c
@@ -840,7 +840,7 @@ static int dra7xx_pcie_probe(struct platform_device *pdev)
 	}
 	dra7xx->mode = mode;
 
-	ret = devm_request_irq(dev, irq, dra7xx_pcie_irq_handler,
+	ret = devm_request_threaded_irq(dev, irq, NULL, dra7xx_pcie_irq_handler,
 			       IRQF_SHARED, "dra7xx-pcie-main", dra7xx);
 	if (ret) {
 		dev_err(dev, "failed to request irq\n");
diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index 02d78a12b6e7..09825b4a075e 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -286,6 +286,7 @@ struct tegra_pcie_dw {
 	struct gpio_desc *pex_refclk_sel_gpiod;
 	unsigned int pex_rst_irq;
 	int ep_state;
+	long link_status;
 };
 
 static inline struct tegra_pcie_dw *to_tegra_pcie(struct dw_pcie *pci)
@@ -449,9 +450,13 @@ static void pex_ep_event_hot_rst_done(struct tegra_pcie_dw *pcie)
 static irqreturn_t tegra_pcie_ep_irq_thread(int irq, void *arg)
 {
 	struct tegra_pcie_dw *pcie = arg;
+	struct dw_pcie_ep *ep = &pcie->pci.ep;
 	struct dw_pcie *pci = &pcie->pci;
 	u32 val, speed;
 
+	if (test_and_clear_bit(0, &pcie->link_status))
+		dw_pcie_ep_linkup(ep);
+
 	speed = dw_pcie_readw_dbi(pci, pcie->pcie_cap_base + PCI_EXP_LNKSTA) &
 		PCI_EXP_LNKSTA_CLS;
 	clk_set_rate(pcie->core_clk, pcie_gen_freq[speed - 1]);
@@ -498,7 +503,6 @@ static irqreturn_t tegra_pcie_ep_irq_thread(int irq, void *arg)
 static irqreturn_t tegra_pcie_ep_hard_irq(int irq, void *arg)
 {
 	struct tegra_pcie_dw *pcie = arg;
-	struct dw_pcie_ep *ep = &pcie->pci.ep;
 	int spurious = 1;
 	u32 status_l0, status_l1, link_status;
 
@@ -514,7 +518,8 @@ static irqreturn_t tegra_pcie_ep_hard_irq(int irq, void *arg)
 			link_status = appl_readl(pcie, APPL_LINK_STATUS);
 			if (link_status & APPL_LINK_STATUS_RDLH_LINK_UP) {
 				dev_dbg(pcie->dev, "Link is up with Host\n");
-				dw_pcie_ep_linkup(ep);
+				set_bit(0, &pcie->link_status);
+				return IRQ_WAKE_THREAD;
 			}
 		}
 
diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
index 55283d2379a6..0f9d2ec822ac 100644
--- a/drivers/pci/endpoint/functions/pci-epf-test.c
+++ b/drivers/pci/endpoint/functions/pci-epf-test.c
@@ -826,33 +826,21 @@ static int pci_epf_test_core_init(struct pci_epf *epf)
 	return 0;
 }
 
-static int pci_epf_test_notifier(struct notifier_block *nb, unsigned long val,
-				 void *data)
+static int pci_epf_test_link_up(struct pci_epf *epf)
 {
-	struct pci_epf *epf = container_of(nb, struct pci_epf, nb);
 	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
-	int ret;
-
-	switch (val) {
-	case CORE_INIT:
-		ret = pci_epf_test_core_init(epf);
-		if (ret)
-			return NOTIFY_BAD;
-		break;
 
-	case LINK_UP:
-		queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler,
-				   msecs_to_jiffies(1));
-		break;
-
-	default:
-		dev_err(&epf->dev, "Invalid EPF test notifier event\n");
-		return NOTIFY_BAD;
-	}
+	queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler,
+			   msecs_to_jiffies(1));
 
-	return NOTIFY_OK;
+	return 0;
 }
 
+static const struct pci_epc_event_ops pci_epf_test_event_ops = {
+	.core_init = pci_epf_test_core_init,
+	.link_up = pci_epf_test_link_up,
+};
+
 static int pci_epf_test_alloc_space(struct pci_epf *epf)
 {
 	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
@@ -979,12 +967,8 @@ static int pci_epf_test_bind(struct pci_epf *epf)
 	if (ret)
 		epf_test->dma_supported = false;
 
-	if (linkup_notifier || core_init_notifier) {
-		epf->nb.notifier_call = pci_epf_test_notifier;
-		pci_epc_register_notifier(epc, &epf->nb);
-	} else {
+	if (!linkup_notifier && !core_init_notifier)
 		queue_work(kpcitest_workqueue, &epf_test->cmd_handler.work);
-	}
 
 	return 0;
 }
@@ -1010,6 +994,8 @@ static int pci_epf_test_probe(struct pci_epf *epf)
 
 	INIT_DELAYED_WORK(&epf_test->cmd_handler, pci_epf_test_cmd_handler);
 
+	epf->event_ops = &pci_epf_test_event_ops;
+
 	epf_set_drvdata(epf, epf_test);
 	return 0;
 }
diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
index dd750ad29485..9440d9811eea 100644
--- a/drivers/pci/endpoint/pci-epc-core.c
+++ b/drivers/pci/endpoint/pci-epc-core.c
@@ -613,7 +613,7 @@ int pci_epc_add_epf(struct pci_epc *epc, struct pci_epf *epf,
 	if (type == SECONDARY_INTERFACE && epf->sec_epc)
 		return -EBUSY;
 
-	mutex_lock(&epc->lock);
+	mutex_lock(&epc->list_lock);
 	func_no = find_first_zero_bit(&epc->function_num_map,
 				      BITS_PER_LONG);
 	if (func_no >= BITS_PER_LONG) {
@@ -640,7 +640,7 @@ int pci_epc_add_epf(struct pci_epc *epc, struct pci_epf *epf,
 
 	list_add_tail(list, &epc->pci_epf);
 ret:
-	mutex_unlock(&epc->lock);
+	mutex_unlock(&epc->list_lock);
 
 	return ret;
 }
@@ -672,11 +672,11 @@ void pci_epc_remove_epf(struct pci_epc *epc, struct pci_epf *epf,
 		list = &epf->sec_epc_list;
 	}
 
-	mutex_lock(&epc->lock);
+	mutex_lock(&epc->list_lock);
 	clear_bit(func_no, &epc->function_num_map);
 	list_del(list);
 	epf->epc = NULL;
-	mutex_unlock(&epc->lock);
+	mutex_unlock(&epc->list_lock);
 }
 EXPORT_SYMBOL_GPL(pci_epc_remove_epf);
 
@@ -690,10 +690,19 @@ EXPORT_SYMBOL_GPL(pci_epc_remove_epf);
  */
 void pci_epc_linkup(struct pci_epc *epc)
 {
+	struct pci_epf *epf;
+
 	if (!epc || IS_ERR(epc))
 		return;
 
-	atomic_notifier_call_chain(&epc->notifier, LINK_UP, NULL);
+	mutex_lock(&epc->list_lock);
+	list_for_each_entry(epf, &epc->pci_epf, list) {
+		mutex_lock(&epf->lock);
+		if (epf->event_ops && epf->event_ops->link_up)
+			epf->event_ops->link_up(epf);
+		mutex_unlock(&epf->lock);
+	}
+	mutex_unlock(&epc->list_lock);
 }
 EXPORT_SYMBOL_GPL(pci_epc_linkup);
 
@@ -707,10 +716,19 @@ EXPORT_SYMBOL_GPL(pci_epc_linkup);
  */
 void pci_epc_init_notify(struct pci_epc *epc)
 {
+	struct pci_epf *epf;
+
 	if (!epc || IS_ERR(epc))
 		return;
 
-	atomic_notifier_call_chain(&epc->notifier, CORE_INIT, NULL);
+	mutex_lock(&epc->list_lock);
+	list_for_each_entry(epf, &epc->pci_epf, list) {
+		mutex_lock(&epf->lock);
+		if (epf->event_ops && epf->event_ops->core_init)
+			epf->event_ops->core_init(epf);
+		mutex_unlock(&epf->lock);
+	}
+	mutex_unlock(&epc->list_lock);
 }
 EXPORT_SYMBOL_GPL(pci_epc_init_notify);
 
@@ -777,8 +795,8 @@ __pci_epc_create(struct device *dev, const struct pci_epc_ops *ops,
 	}
 
 	mutex_init(&epc->lock);
+	mutex_init(&epc->list_lock);
 	INIT_LIST_HEAD(&epc->pci_epf);
-	ATOMIC_INIT_NOTIFIER_HEAD(&epc->notifier);
 
 	device_initialize(&epc->dev);
 	epc->dev.class = pci_epc_class;
diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
index a48778e1a4ee..301bb0e53707 100644
--- a/include/linux/pci-epc.h
+++ b/include/linux/pci-epc.h
@@ -122,6 +122,7 @@ struct pci_epc_mem {
  * struct pci_epc - represents the PCI EPC device
  * @dev: PCI EPC device
  * @pci_epf: list of endpoint functions present in this EPC device
+ * list_lock: Mutex for protecting pci_epf list
  * @ops: function pointers for performing endpoint operations
  * @windows: array of address space of the endpoint controller
  * @mem: first window of the endpoint controller, which corresponds to
@@ -134,11 +135,11 @@ struct pci_epc_mem {
  * @group: configfs group representing the PCI EPC device
  * @lock: mutex to protect pci_epc ops
  * @function_num_map: bitmap to manage physical function number
- * @notifier: used to notify EPF of any EPC events (like linkup)
  */
 struct pci_epc {
 	struct device			dev;
 	struct list_head		pci_epf;
+	struct mutex			list_lock;
 	const struct pci_epc_ops	*ops;
 	struct pci_epc_mem		**windows;
 	struct pci_epc_mem		*mem;
@@ -149,7 +150,6 @@ struct pci_epc {
 	/* mutex to protect against concurrent access of EP controller */
 	struct mutex			lock;
 	unsigned long			function_num_map;
-	struct atomic_notifier_head	notifier;
 };
 
 /**
@@ -192,12 +192,6 @@ static inline void *epc_get_drvdata(struct pci_epc *epc)
 	return dev_get_drvdata(&epc->dev);
 }
 
-static inline int
-pci_epc_register_notifier(struct pci_epc *epc, struct notifier_block *nb)
-{
-	return atomic_notifier_chain_register(&epc->notifier, nb);
-}
-
 struct pci_epc *
 __devm_pci_epc_create(struct device *dev, const struct pci_epc_ops *ops,
 		      struct module *owner);
diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h
index 009a07147c61..a215dc8ce693 100644
--- a/include/linux/pci-epf.h
+++ b/include/linux/pci-epf.h
@@ -17,11 +17,6 @@
 struct pci_epf;
 enum pci_epc_interface_type;
 
-enum pci_notify_event {
-	CORE_INIT,
-	LINK_UP,
-};
-
 enum pci_barno {
 	NO_BAR = -1,
 	BAR_0,
@@ -73,6 +68,16 @@ struct pci_epf_ops {
 };
 
 /**
+ * struct pci_epf_event_ops - Callbacks for capturing the EPC events
+ * @core_init: Callback for the EPC initialization complete event
+ * @link_up: Callback for the EPC link up event
+ */
+struct pci_epc_event_ops {
+	int (*core_init)(struct pci_epf *epf);
+	int (*link_up)(struct pci_epf *epf);
+};
+
+/**
  * struct pci_epf_driver - represents the PCI EPF driver
  * @probe: ops to perform when a new EPF device has been bound to the EPF driver
  * @remove: ops to perform when the binding between the EPF device and EPF
@@ -127,7 +132,6 @@ struct pci_epf_bar {
  * @epf_pf: the physical EPF device to which this virtual EPF device is bound
  * @driver: the EPF driver to which this EPF device is bound
  * @list: to add pci_epf as a list of PCI endpoint functions to pci_epc
- * @nb: notifier block to notify EPF of any EPC events (like linkup)
  * @lock: mutex to protect pci_epf_ops
  * @sec_epc: the secondary EPC device to which this EPF device is bound
  * @sec_epc_list: to add pci_epf as list of PCI endpoint functions to secondary
@@ -139,6 +143,7 @@ struct pci_epf_bar {
  * @is_vf: true - virtual function, false - physical function
  * @vfunction_num_map: bitmap to manage virtual function number
  * @pci_vepf: list of virtual endpoint functions associated with this function
+ * @event_ops: Callbacks for capturing the EPC events
  */
 struct pci_epf {
 	struct device		dev;
@@ -154,7 +159,6 @@ struct pci_epf {
 	struct pci_epf		*epf_pf;
 	struct pci_epf_driver	*driver;
 	struct list_head	list;
-	struct notifier_block   nb;
 	/* mutex to protect against concurrent access of pci_epf_ops */
 	struct mutex		lock;
 
@@ -168,6 +172,7 @@ struct pci_epf {
 	unsigned int		is_vf;
 	unsigned long		vfunction_num_map;
 	struct list_head	pci_vepf;
+	const struct pci_epc_event_ops *event_ops;
 };
 
 /**