From 869bc52534065990cb57013b2bb354c0c1e66c5c Mon Sep 17 00:00:00 2001
From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Date: Wed, 27 Mar 2024 14:43:30 +0530
Subject: [PATCH 1/8] PCI: dwc: ep: Fix DBI access failure for drivers
 requiring refclk from host
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The DWC glue drivers requiring an active reference clock from the PCIe host
for initializing their PCIe EP core, set a flag called 'core_init_notifier'
to let DWC driver know that these drivers need a special attention during
initialization. In these drivers, access to the hw registers (like DBI)
before receiving the active refclk from host will result in access failure
and also could cause a whole system hang.

But the current DWC EP driver doesn't honor the requirements of the drivers
setting 'core_init_notifier' flag and tries to access the DBI registers
during dw_pcie_ep_init(). This causes the system hang for glue drivers such
as Tegra194 and Qcom EP as they depend on refclk from host and have set the
above mentioned flag.

To workaround this issue, users of the affected platforms have to maintain
the dependency with the PCIe host by booting the PCIe EP after host boot.
But this won't provide a good user experience, since PCIe EP is _one_ of
the features of those platforms and it doesn't make sense to delay the
whole platform booting due to PCIe requiring active refclk.

So to fix this issue, let's move all the DBI access from
dw_pcie_ep_init() in the DWC EP driver to the dw_pcie_ep_init_complete()
API. This API will only be called by the drivers setting
'core_init_notifier' flag once refclk is received from host. For the rest
of the drivers that gets the refclk locally, this API will be called
within dw_pcie_ep_init().

Link: https://lore.kernel.org/linux-pci/20240327-pci-dbi-rework-v12-1-082625472414@linaro.org
Fixes: e966f7390da9 ("PCI: dwc: Refactor core initialization code for EP mode")
Co-developed-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
---
 .../pci/controller/dwc/pcie-designware-ep.c   | 120 +++++++++++-------
 1 file changed, 71 insertions(+), 49 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index 746a11dcb67f..c43a1479de2c 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -604,11 +604,16 @@ static unsigned int dw_pcie_ep_find_ext_capability(struct dw_pcie *pci, int cap)
 int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+	struct dw_pcie_ep_func *ep_func;
+	struct device *dev = pci->dev;
+	struct pci_epc *epc = ep->epc;
 	unsigned int offset, ptm_cap_base;
 	unsigned int nbars;
 	u8 hdr_type;
+	u8 func_no;
+	int i, ret;
+	void *addr;
 	u32 reg;
-	int i;
 
 	hdr_type = dw_pcie_readb_dbi(pci, PCI_HEADER_TYPE) &
 		   PCI_HEADER_TYPE_MASK;
@@ -619,6 +624,58 @@ int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep)
 		return -EIO;
 	}
 
+	dw_pcie_version_detect(pci);
+
+	dw_pcie_iatu_detect(pci);
+
+	ret = dw_pcie_edma_detect(pci);
+	if (ret)
+		return ret;
+
+	if (!ep->ib_window_map) {
+		ep->ib_window_map = devm_bitmap_zalloc(dev, pci->num_ib_windows,
+						       GFP_KERNEL);
+		if (!ep->ib_window_map)
+			goto err_remove_edma;
+	}
+
+	if (!ep->ob_window_map) {
+		ep->ob_window_map = devm_bitmap_zalloc(dev, pci->num_ob_windows,
+						       GFP_KERNEL);
+		if (!ep->ob_window_map)
+			goto err_remove_edma;
+	}
+
+	if (!ep->outbound_addr) {
+		addr = devm_kcalloc(dev, pci->num_ob_windows, sizeof(phys_addr_t),
+				    GFP_KERNEL);
+		if (!addr)
+			goto err_remove_edma;
+		ep->outbound_addr = addr;
+	}
+
+	for (func_no = 0; func_no < epc->max_functions; func_no++) {
+
+		ep_func = dw_pcie_ep_get_func_from_ep(ep, func_no);
+		if (ep_func)
+			continue;
+
+		ep_func = devm_kzalloc(dev, sizeof(*ep_func), GFP_KERNEL);
+		if (!ep_func)
+			goto err_remove_edma;
+
+		ep_func->func_no = func_no;
+		ep_func->msi_cap = dw_pcie_ep_find_capability(ep, func_no,
+							      PCI_CAP_ID_MSI);
+		ep_func->msix_cap = dw_pcie_ep_find_capability(ep, func_no,
+							       PCI_CAP_ID_MSIX);
+
+		list_add_tail(&ep_func->list, &ep->func_list);
+	}
+
+	if (ep->ops->init)
+		ep->ops->init(ep);
+
 	offset = dw_pcie_ep_find_ext_capability(pci, PCI_EXT_CAP_ID_REBAR);
 	ptm_cap_base = dw_pcie_ep_find_ext_capability(pci, PCI_EXT_CAP_ID_PTM);
 
@@ -658,14 +715,17 @@ int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep)
 	dw_pcie_dbi_ro_wr_dis(pci);
 
 	return 0;
+
+err_remove_edma:
+	dw_pcie_edma_remove(pci);
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(dw_pcie_ep_init_complete);
 
 int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 {
 	int ret;
-	void *addr;
-	u8 func_no;
 	struct resource *res;
 	struct pci_epc *epc;
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
@@ -673,7 +733,6 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 	struct platform_device *pdev = to_platform_device(dev);
 	struct device_node *np = dev->of_node;
 	const struct pci_epc_features *epc_features;
-	struct dw_pcie_ep_func *ep_func;
 
 	INIT_LIST_HEAD(&ep->func_list);
 
@@ -691,26 +750,6 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 	if (ep->ops->pre_init)
 		ep->ops->pre_init(ep);
 
-	dw_pcie_version_detect(pci);
-
-	dw_pcie_iatu_detect(pci);
-
-	ep->ib_window_map = devm_bitmap_zalloc(dev, pci->num_ib_windows,
-					       GFP_KERNEL);
-	if (!ep->ib_window_map)
-		return -ENOMEM;
-
-	ep->ob_window_map = devm_bitmap_zalloc(dev, pci->num_ob_windows,
-					       GFP_KERNEL);
-	if (!ep->ob_window_map)
-		return -ENOMEM;
-
-	addr = devm_kcalloc(dev, pci->num_ob_windows, sizeof(phys_addr_t),
-			    GFP_KERNEL);
-	if (!addr)
-		return -ENOMEM;
-	ep->outbound_addr = addr;
-
 	epc = devm_pci_epc_create(dev, &epc_ops);
 	if (IS_ERR(epc)) {
 		dev_err(dev, "Failed to create epc device\n");
@@ -724,23 +763,6 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 	if (ret < 0)
 		epc->max_functions = 1;
 
-	for (func_no = 0; func_no < epc->max_functions; func_no++) {
-		ep_func = devm_kzalloc(dev, sizeof(*ep_func), GFP_KERNEL);
-		if (!ep_func)
-			return -ENOMEM;
-
-		ep_func->func_no = func_no;
-		ep_func->msi_cap = dw_pcie_ep_find_capability(ep, func_no,
-							      PCI_CAP_ID_MSI);
-		ep_func->msix_cap = dw_pcie_ep_find_capability(ep, func_no,
-							       PCI_CAP_ID_MSIX);
-
-		list_add_tail(&ep_func->list, &ep->func_list);
-	}
-
-	if (ep->ops->init)
-		ep->ops->init(ep);
-
 	ret = pci_epc_mem_init(epc, ep->phys_base, ep->addr_size,
 			       ep->page_size);
 	if (ret < 0) {
@@ -756,25 +778,25 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 		goto err_exit_epc_mem;
 	}
 
-	ret = dw_pcie_edma_detect(pci);
-	if (ret)
-		goto err_free_epc_mem;
-
 	if (ep->ops->get_features) {
 		epc_features = ep->ops->get_features(ep);
 		if (epc_features->core_init_notifier)
 			return 0;
 	}
 
+	/*
+	 * NOTE:- Avoid accessing the hardware (Ex:- DBI space) before this
+	 * step as platforms that implement 'core_init_notifier' feature may
+	 * not have the hardware ready (i.e. core initialized) for access
+	 * (Ex: tegra194). Any hardware access on such platforms result
+	 * in system hang.
+	 */
 	ret = dw_pcie_ep_init_complete(ep);
 	if (ret)
-		goto err_remove_edma;
+		goto err_free_epc_mem;
 
 	return 0;
 
-err_remove_edma:
-	dw_pcie_edma_remove(pci);
-
 err_free_epc_mem:
 	pci_epc_mem_free_addr(epc, ep->msi_mem_phys, ep->msi_mem,
 			      epc->mem->window.page_size);

From 7cbebc86c72aa215802ad159d60ecaf9a20d5530 Mon Sep 17 00:00:00 2001
From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Date: Wed, 27 Mar 2024 14:43:31 +0530
Subject: [PATCH 2/8] PCI: dwc: ep: Add Kernel-doc comments for APIs
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

All of the APIs are missing the Kernel-doc comments. Hence, add them.

Link: https://lore.kernel.org/linux-pci/20240327-pci-dbi-rework-v12-2-082625472414@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
---
 .../pci/controller/dwc/pcie-designware-ep.c   | 77 +++++++++++++++++++
 1 file changed, 77 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index c43a1479de2c..dc63478f6910 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -15,6 +15,10 @@
 #include <linux/pci-epc.h>
 #include <linux/pci-epf.h>
 
+/**
+ * dw_pcie_ep_linkup - Notify EPF drivers about Link Up event
+ * @ep: DWC EP device
+ */
 void dw_pcie_ep_linkup(struct dw_pcie_ep *ep)
 {
 	struct pci_epc *epc = ep->epc;
@@ -23,6 +27,10 @@ void dw_pcie_ep_linkup(struct dw_pcie_ep *ep)
 }
 EXPORT_SYMBOL_GPL(dw_pcie_ep_linkup);
 
+/**
+ * dw_pcie_ep_init_notify - Notify EPF drivers about EPC initialization complete
+ * @ep: DWC EP device
+ */
 void dw_pcie_ep_init_notify(struct dw_pcie_ep *ep)
 {
 	struct pci_epc *epc = ep->epc;
@@ -31,6 +39,14 @@ void dw_pcie_ep_init_notify(struct dw_pcie_ep *ep)
 }
 EXPORT_SYMBOL_GPL(dw_pcie_ep_init_notify);
 
+/**
+ * dw_pcie_ep_get_func_from_ep - Get the struct dw_pcie_ep_func corresponding to
+ *				 the endpoint function
+ * @ep: DWC EP device
+ * @func_no: Function number of the endpoint device
+ *
+ * Return: struct dw_pcie_ep_func if success, NULL otherwise.
+ */
 struct dw_pcie_ep_func *
 dw_pcie_ep_get_func_from_ep(struct dw_pcie_ep *ep, u8 func_no)
 {
@@ -61,6 +77,11 @@ static void __dw_pcie_ep_reset_bar(struct dw_pcie *pci, u8 func_no,
 	dw_pcie_dbi_ro_wr_dis(pci);
 }
 
+/**
+ * dw_pcie_ep_reset_bar - Reset endpoint BAR
+ * @pci: DWC PCI device
+ * @bar: BAR number of the endpoint
+ */
 void dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum pci_barno bar)
 {
 	u8 func_no, funcs;
@@ -440,6 +461,13 @@ static const struct pci_epc_ops epc_ops = {
 	.get_features		= dw_pcie_ep_get_features,
 };
 
+/**
+ * dw_pcie_ep_raise_intx_irq - Raise INTx IRQ to the host
+ * @ep: DWC EP device
+ * @func_no: Function number of the endpoint
+ *
+ * Return: 0 if success, errono otherwise.
+ */
 int dw_pcie_ep_raise_intx_irq(struct dw_pcie_ep *ep, u8 func_no)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
@@ -451,6 +479,14 @@ int dw_pcie_ep_raise_intx_irq(struct dw_pcie_ep *ep, u8 func_no)
 }
 EXPORT_SYMBOL_GPL(dw_pcie_ep_raise_intx_irq);
 
+/**
+ * dw_pcie_ep_raise_msi_irq - Raise MSI IRQ to the host
+ * @ep: DWC EP device
+ * @func_no: Function number of the endpoint
+ * @interrupt_num: Interrupt number to be raised
+ *
+ * Return: 0 if success, errono otherwise.
+ */
 int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
 			     u8 interrupt_num)
 {
@@ -500,6 +536,15 @@ int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
 }
 EXPORT_SYMBOL_GPL(dw_pcie_ep_raise_msi_irq);
 
+/**
+ * dw_pcie_ep_raise_msix_irq_doorbell - Raise MSI-X to the host using Doorbell
+ *					method
+ * @ep: DWC EP device
+ * @func_no: Function number of the endpoint device
+ * @interrupt_num: Interrupt number to be raised
+ *
+ * Return: 0 if success, errno otherwise.
+ */
 int dw_pcie_ep_raise_msix_irq_doorbell(struct dw_pcie_ep *ep, u8 func_no,
 				       u16 interrupt_num)
 {
@@ -519,6 +564,14 @@ int dw_pcie_ep_raise_msix_irq_doorbell(struct dw_pcie_ep *ep, u8 func_no,
 	return 0;
 }
 
+/**
+ * dw_pcie_ep_raise_msix_irq - Raise MSI-X to the host
+ * @ep: DWC EP device
+ * @func_no: Function number of the endpoint device
+ * @interrupt_num: Interrupt number to be raised
+ *
+ * Return: 0 if success, errno otherwise.
+ */
 int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
 			      u16 interrupt_num)
 {
@@ -566,6 +619,13 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
 	return 0;
 }
 
+/**
+ * dw_pcie_ep_exit - Deinitialize the endpoint device
+ * @ep: DWC EP device
+ *
+ * Deinitialize the endpoint device. EPC device is not destroyed since that will
+ * be taken care by Devres.
+ */
 void dw_pcie_ep_exit(struct dw_pcie_ep *ep)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
@@ -601,6 +661,14 @@ static unsigned int dw_pcie_ep_find_ext_capability(struct dw_pcie *pci, int cap)
 	return 0;
 }
 
+/**
+ * dw_pcie_ep_init_complete - Complete DWC EP initialization
+ * @ep: DWC EP device
+ *
+ * Complete the initialization of the registers (CSRs) specific to DWC EP. This
+ * API should be called only when the endpoint receives an active refclk (either
+ * from host or generated locally).
+ */
 int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
@@ -723,6 +791,15 @@ err_remove_edma:
 }
 EXPORT_SYMBOL_GPL(dw_pcie_ep_init_complete);
 
+/**
+ * dw_pcie_ep_init - Initialize the endpoint device
+ * @ep: DWC EP device
+ *
+ * Initialize the endpoint device. Allocate resources and create the EPC
+ * device with the endpoint framework.
+ *
+ * Return: 0 if success, errno otherwise.
+ */
 int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 {
 	int ret;

From b7dec6b85089fcadf2478e22429d4e1863f95294 Mon Sep 17 00:00:00 2001
From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Date: Wed, 27 Mar 2024 14:43:32 +0530
Subject: [PATCH 3/8] PCI: dwc: ep: Remove deinit() callback from struct
 dw_pcie_ep_ops
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

deinit() callback was solely introduced for the pcie-rcar-gen4 driver where
it is used to do platform specific resource deallocation. And this callback
is called right at the end of the dw_pcie_ep_exit() API. So it doesn't
matter whether it is called within or outside of dw_pcie_ep_exit() API.

So let's remove this callback and directly call rcar_gen4_pcie_ep_deinit()
in pcie-rcar-gen4 driver to do resource deallocation after the completion
of dw_pcie_ep_exit() API in rcar_gen4_remove_dw_pcie_ep().

This simplifies the DWC layer.

Link: https://lore.kernel.org/linux-pci/20240327-pci-dbi-rework-v12-3-082625472414@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
---
 drivers/pci/controller/dwc/pcie-designware-ep.c |  9 +--------
 drivers/pci/controller/dwc/pcie-designware.h    |  1 -
 drivers/pci/controller/dwc/pcie-rcar-gen4.c     | 14 ++++++++------
 3 files changed, 9 insertions(+), 15 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index dc63478f6910..f06598715412 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -637,9 +637,6 @@ void dw_pcie_ep_exit(struct dw_pcie_ep *ep)
 			      epc->mem->window.page_size);
 
 	pci_epc_mem_exit(epc);
-
-	if (ep->ops->deinit)
-		ep->ops->deinit(ep);
 }
 EXPORT_SYMBOL_GPL(dw_pcie_ep_exit);
 
@@ -844,7 +841,7 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 			       ep->page_size);
 	if (ret < 0) {
 		dev_err(dev, "Failed to initialize address space\n");
-		goto err_ep_deinit;
+		return ret;
 	}
 
 	ep->msi_mem = pci_epc_mem_alloc_addr(epc, &ep->msi_mem_phys,
@@ -881,10 +878,6 @@ err_free_epc_mem:
 err_exit_epc_mem:
 	pci_epc_mem_exit(epc);
 
-err_ep_deinit:
-	if (ep->ops->deinit)
-		ep->ops->deinit(ep);
-
 	return ret;
 }
 EXPORT_SYMBOL_GPL(dw_pcie_ep_init);
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 26dae4837462..ab7431a37209 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -333,7 +333,6 @@ struct dw_pcie_rp {
 struct dw_pcie_ep_ops {
 	void	(*pre_init)(struct dw_pcie_ep *ep);
 	void	(*init)(struct dw_pcie_ep *ep);
-	void	(*deinit)(struct dw_pcie_ep *ep);
 	int	(*raise_irq)(struct dw_pcie_ep *ep, u8 func_no,
 			     unsigned int type, u16 interrupt_num);
 	const struct pci_epc_features* (*get_features)(struct dw_pcie_ep *ep);
diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
index 0be760ed420b..5d29c4cfe0a0 100644
--- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
+++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
@@ -352,11 +352,8 @@ static void rcar_gen4_pcie_ep_init(struct dw_pcie_ep *ep)
 		dw_pcie_ep_reset_bar(pci, bar);
 }
 
-static void rcar_gen4_pcie_ep_deinit(struct dw_pcie_ep *ep)
+static void rcar_gen4_pcie_ep_deinit(struct rcar_gen4_pcie *rcar)
 {
-	struct dw_pcie *dw = to_dw_pcie_from_ep(ep);
-	struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw);
-
 	writel(0, rcar->base + PCIEDMAINTSTSEN);
 	rcar_gen4_pcie_common_deinit(rcar);
 }
@@ -410,7 +407,6 @@ static unsigned int rcar_gen4_pcie_ep_get_dbi2_offset(struct dw_pcie_ep *ep,
 static const struct dw_pcie_ep_ops pcie_ep_ops = {
 	.pre_init = rcar_gen4_pcie_ep_pre_init,
 	.init = rcar_gen4_pcie_ep_init,
-	.deinit = rcar_gen4_pcie_ep_deinit,
 	.raise_irq = rcar_gen4_pcie_ep_raise_irq,
 	.get_features = rcar_gen4_pcie_ep_get_features,
 	.get_dbi_offset = rcar_gen4_pcie_ep_get_dbi_offset,
@@ -420,18 +416,24 @@ static const struct dw_pcie_ep_ops pcie_ep_ops = {
 static int rcar_gen4_add_dw_pcie_ep(struct rcar_gen4_pcie *rcar)
 {
 	struct dw_pcie_ep *ep = &rcar->dw.ep;
+	int ret;
 
 	if (!IS_ENABLED(CONFIG_PCIE_RCAR_GEN4_EP))
 		return -ENODEV;
 
 	ep->ops = &pcie_ep_ops;
 
-	return dw_pcie_ep_init(ep);
+	ret = dw_pcie_ep_init(ep);
+	if (ret)
+		rcar_gen4_pcie_ep_deinit(rcar);
+
+	return ret;
 }
 
 static void rcar_gen4_remove_dw_pcie_ep(struct rcar_gen4_pcie *rcar)
 {
 	dw_pcie_ep_exit(&rcar->dw.ep);
+	rcar_gen4_pcie_ep_deinit(rcar);
 }
 
 /* Common */

From c8682a3314c1e247b253a5ffa22e8cc4cd7156cc Mon Sep 17 00:00:00 2001
From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Date: Wed, 27 Mar 2024 14:43:33 +0530
Subject: [PATCH 4/8] PCI: dwc: ep: Rename dw_pcie_ep_exit() to
 dw_pcie_ep_deinit()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

dw_pcie_ep_exit() API is undoing what the dw_pcie_ep_init() API has done
already (at least partly). But the API name dw_pcie_ep_exit() is not quite
reflecting that. So let's rename it to dw_pcie_ep_deinit() to make the
purpose of this API clear. This also aligns with the DWC host driver.

Link: https://patchwork.kernel.org/project/linux-pci/patch/20240327-pci-dbi-rework-v12-4-082625472414@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
---
 drivers/pci/controller/dwc/pcie-designware-ep.c | 6 +++---
 drivers/pci/controller/dwc/pcie-designware.h    | 4 ++--
 drivers/pci/controller/dwc/pcie-rcar-gen4.c     | 2 +-
 3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index f06598715412..d87f7642d7f6 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -620,13 +620,13 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
 }
 
 /**
- * dw_pcie_ep_exit - Deinitialize the endpoint device
+ * dw_pcie_ep_deinit - Deinitialize the endpoint device
  * @ep: DWC EP device
  *
  * Deinitialize the endpoint device. EPC device is not destroyed since that will
  * be taken care by Devres.
  */
-void dw_pcie_ep_exit(struct dw_pcie_ep *ep)
+void dw_pcie_ep_deinit(struct dw_pcie_ep *ep)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
 	struct pci_epc *epc = ep->epc;
@@ -638,7 +638,7 @@ void dw_pcie_ep_exit(struct dw_pcie_ep *ep)
 
 	pci_epc_mem_exit(epc);
 }
-EXPORT_SYMBOL_GPL(dw_pcie_ep_exit);
+EXPORT_SYMBOL_GPL(dw_pcie_ep_deinit);
 
 static unsigned int dw_pcie_ep_find_ext_capability(struct dw_pcie *pci, int cap)
 {
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index ab7431a37209..61465203bb60 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -671,7 +671,7 @@ void dw_pcie_ep_linkup(struct dw_pcie_ep *ep);
 int dw_pcie_ep_init(struct dw_pcie_ep *ep);
 int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep);
 void dw_pcie_ep_init_notify(struct dw_pcie_ep *ep);
-void dw_pcie_ep_exit(struct dw_pcie_ep *ep);
+void dw_pcie_ep_deinit(struct dw_pcie_ep *ep);
 int dw_pcie_ep_raise_intx_irq(struct dw_pcie_ep *ep, u8 func_no);
 int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
 			     u8 interrupt_num);
@@ -701,7 +701,7 @@ static inline void dw_pcie_ep_init_notify(struct dw_pcie_ep *ep)
 {
 }
 
-static inline void dw_pcie_ep_exit(struct dw_pcie_ep *ep)
+static inline void dw_pcie_ep_deinit(struct dw_pcie_ep *ep)
 {
 }
 
diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
index 5d29c4cfe0a0..de4bdfaecab3 100644
--- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
+++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
@@ -432,7 +432,7 @@ static int rcar_gen4_add_dw_pcie_ep(struct rcar_gen4_pcie *rcar)
 
 static void rcar_gen4_remove_dw_pcie_ep(struct rcar_gen4_pcie *rcar)
 {
-	dw_pcie_ep_exit(&rcar->dw.ep);
+	dw_pcie_ep_deinit(&rcar->dw.ep);
 	rcar_gen4_pcie_ep_deinit(rcar);
 }
 

From 570d7715eed8a29ac5bd96c7694f060a991e5a31 Mon Sep 17 00:00:00 2001
From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Date: Wed, 27 Mar 2024 14:43:34 +0530
Subject: [PATCH 5/8] PCI: dwc: ep: Introduce dw_pcie_ep_cleanup() API for
 drivers supporting PERST#
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

For DWC glue drivers supporting PERST# (currently Qcom and Tegra194), some
of the DWC resources like eDMA should be cleaned up during the PERST#
assert time.

So let's introduce a dw_pcie_ep_cleanup() API that could be called by these
drivers to cleanup the DWC specific resources. Currently, it just removes
eDMA.

Closes: https://lore.kernel.org/linux-pci/ZWYmX8Y%2F7Q9WMxES@x1-carbon
Link: https://lore.kernel.org/linux-pci/20240327-pci-dbi-rework-v12-5-082625472414@linaro.org
Reported-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
---
 .../pci/controller/dwc/pcie-designware-ep.c   | 19 +++++++++++++++++--
 drivers/pci/controller/dwc/pcie-designware.h  |  5 +++++
 drivers/pci/controller/dwc/pcie-qcom-ep.c     |  1 +
 drivers/pci/controller/dwc/pcie-tegra194.c    |  2 ++
 4 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index d87f7642d7f6..eeff7f1ff8f1 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -619,6 +619,22 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
 	return 0;
 }
 
+/**
+ * dw_pcie_ep_cleanup - Cleanup DWC EP resources after fundamental reset
+ * @ep: DWC EP device
+ *
+ * Cleans up the DWC EP specific resources like eDMA etc... after fundamental
+ * reset like PERST#. Note that this API is only applicable for drivers
+ * supporting PERST# or any other methods of fundamental reset.
+ */
+void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep)
+{
+	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+
+	dw_pcie_edma_remove(pci);
+}
+EXPORT_SYMBOL_GPL(dw_pcie_ep_cleanup);
+
 /**
  * dw_pcie_ep_deinit - Deinitialize the endpoint device
  * @ep: DWC EP device
@@ -628,10 +644,9 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
  */
 void dw_pcie_ep_deinit(struct dw_pcie_ep *ep)
 {
-	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
 	struct pci_epc *epc = ep->epc;
 
-	dw_pcie_edma_remove(pci);
+	dw_pcie_ep_cleanup(ep);
 
 	pci_epc_mem_free_addr(epc, ep->msi_mem_phys, ep->msi_mem,
 			      epc->mem->window.page_size);
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 61465203bb60..351d2fe3ea4d 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -672,6 +672,7 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep);
 int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep);
 void dw_pcie_ep_init_notify(struct dw_pcie_ep *ep);
 void dw_pcie_ep_deinit(struct dw_pcie_ep *ep);
+void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep);
 int dw_pcie_ep_raise_intx_irq(struct dw_pcie_ep *ep, u8 func_no);
 int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
 			     u8 interrupt_num);
@@ -705,6 +706,10 @@ static inline void dw_pcie_ep_deinit(struct dw_pcie_ep *ep)
 {
 }
 
+static inline void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep)
+{
+}
+
 static inline int dw_pcie_ep_raise_intx_irq(struct dw_pcie_ep *ep, u8 func_no)
 {
 	return 0;
diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c
index 36e5e80cd22f..59b1c0110288 100644
--- a/drivers/pci/controller/dwc/pcie-qcom-ep.c
+++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c
@@ -507,6 +507,7 @@ static void qcom_pcie_perst_assert(struct dw_pcie *pci)
 		return;
 	}
 
+	dw_pcie_ep_cleanup(&pci->ep);
 	qcom_pcie_disable_resources(pcie_ep);
 	pcie_ep->link_status = QCOM_PCIE_EP_LINK_DISABLED;
 }
diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index 1f7b662cb8e1..26ea2f8313eb 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -1715,6 +1715,8 @@ static void pex_ep_event_pex_rst_assert(struct tegra_pcie_dw *pcie)
 	if (ret)
 		dev_err(pcie->dev, "Failed to go Detect state: %d\n", ret);
 
+	dw_pcie_ep_cleanup(&pcie->pci.ep);
+
 	reset_control_assert(pcie->core_rst);
 
 	tegra_pcie_disable_phy(pcie);

From 7d6e64c443ea03090b01ae2fe401a78a68427ddc Mon Sep 17 00:00:00 2001
From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Date: Wed, 27 Mar 2024 14:43:35 +0530
Subject: [PATCH 6/8] PCI: dwc: ep: Rename dw_pcie_ep_init_complete() to
 dw_pcie_ep_init_registers()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The goal of the dw_pcie_ep_init_complete() API is to initialize the DWC
specific registers post registering the controller with the EP framework.

But the naming doesn't reflect its functionality and causes confusion. So,
let's rename it to dw_pcie_ep_init_registers() to make it clear that it
initializes the DWC specific registers.

Link: https://lore.kernel.org/linux-pci/20240327-pci-dbi-rework-v12-6-082625472414@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
---
 drivers/pci/controller/dwc/pcie-designware-ep.c | 14 +++++++-------
 drivers/pci/controller/dwc/pcie-designware.h    |  4 ++--
 drivers/pci/controller/dwc/pcie-qcom-ep.c       |  2 +-
 drivers/pci/controller/dwc/pcie-tegra194.c      |  2 +-
 4 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index eeff7f1ff8f1..761d3012a073 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -674,14 +674,14 @@ static unsigned int dw_pcie_ep_find_ext_capability(struct dw_pcie *pci, int cap)
 }
 
 /**
- * dw_pcie_ep_init_complete - Complete DWC EP initialization
+ * dw_pcie_ep_init_registers - Initialize DWC EP specific registers
  * @ep: DWC EP device
  *
- * Complete the initialization of the registers (CSRs) specific to DWC EP. This
- * API should be called only when the endpoint receives an active refclk (either
- * from host or generated locally).
+ * Initialize the registers (CSRs) specific to DWC EP. This API should be called
+ * only when the endpoint receives an active refclk (either from host or
+ * generated locally).
  */
-int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep)
+int dw_pcie_ep_init_registers(struct dw_pcie_ep *ep)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
 	struct dw_pcie_ep_func *ep_func;
@@ -801,7 +801,7 @@ err_remove_edma:
 
 	return ret;
 }
-EXPORT_SYMBOL_GPL(dw_pcie_ep_init_complete);
+EXPORT_SYMBOL_GPL(dw_pcie_ep_init_registers);
 
 /**
  * dw_pcie_ep_init - Initialize the endpoint device
@@ -880,7 +880,7 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 	 * (Ex: tegra194). Any hardware access on such platforms result
 	 * in system hang.
 	 */
-	ret = dw_pcie_ep_init_complete(ep);
+	ret = dw_pcie_ep_init_registers(ep);
 	if (ret)
 		goto err_free_epc_mem;
 
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 351d2fe3ea4d..f8e5431a207b 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -669,7 +669,7 @@ static inline void __iomem *dw_pcie_own_conf_map_bus(struct pci_bus *bus,
 #ifdef CONFIG_PCIE_DW_EP
 void dw_pcie_ep_linkup(struct dw_pcie_ep *ep);
 int dw_pcie_ep_init(struct dw_pcie_ep *ep);
-int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep);
+int dw_pcie_ep_init_registers(struct dw_pcie_ep *ep);
 void dw_pcie_ep_init_notify(struct dw_pcie_ep *ep);
 void dw_pcie_ep_deinit(struct dw_pcie_ep *ep);
 void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep);
@@ -693,7 +693,7 @@ static inline int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 	return 0;
 }
 
-static inline int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep)
+static inline int dw_pcie_ep_init_registers(struct dw_pcie_ep *ep)
 {
 	return 0;
 }
diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c
index 59b1c0110288..3697b4a944cc 100644
--- a/drivers/pci/controller/dwc/pcie-qcom-ep.c
+++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c
@@ -463,7 +463,7 @@ static int qcom_pcie_perst_deassert(struct dw_pcie *pci)
 	      PARF_INT_ALL_LINK_UP | PARF_INT_ALL_EDMA;
 	writel_relaxed(val, pcie_ep->parf + PARF_INT_ALL_MASK);
 
-	ret = dw_pcie_ep_init_complete(&pcie_ep->pci.ep);
+	ret = dw_pcie_ep_init_registers(&pcie_ep->pci.ep);
 	if (ret) {
 		dev_err(dev, "Failed to complete initialization: %d\n", ret);
 		goto err_disable_resources;
diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index 26ea2f8313eb..db043f579fbe 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -1897,7 +1897,7 @@ static void pex_ep_event_pex_rst_deassert(struct tegra_pcie_dw *pcie)
 	val = (upper_32_bits(ep->msi_mem_phys) & MSIX_ADDR_MATCH_HIGH_OFF_MASK);
 	dw_pcie_writel_dbi(pci, MSIX_ADDR_MATCH_HIGH_OFF, val);
 
-	ret = dw_pcie_ep_init_complete(ep);
+	ret = dw_pcie_ep_init_registers(ep);
 	if (ret) {
 		dev_err(dev, "Failed to complete initialization: %d\n", ret);
 		goto fail_init_complete;

From df69e17ccc2f87bd6ce7a862dcdce16ae55a7fd7 Mon Sep 17 00:00:00 2001
From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Date: Wed, 27 Mar 2024 14:43:36 +0530
Subject: [PATCH 7/8] PCI: dwc: ep: Call dw_pcie_ep_init_registers() API
 directly from all glue drivers
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Currently, dw_pcie_ep_init_registers() API is directly called by the glue
drivers requiring active refclk from host. But for the other drivers, it is
getting called implicitly by dw_pcie_ep_init(). This is due to the fact
that this API initializes DWC EP specific registers and that requires an
active refclk (either from host or generated locally by endpoint itsef).

But, this causes a discrepancy among the glue drivers. So to avoid this
confusion, let's call this API directly from all glue drivers irrespective
of refclk dependency. Only difference here is that the drivers requiring
refclk from host will call this API only after the refclk is received and
other drivers without refclk dependency will call this API right after
dw_pcie_ep_init().

With this change, the check for 'core_init_notifier' flag can now be
dropped from dw_pcie_ep_init() API. This will also allow us to remove the
'core_init_notifier' flag completely in the later commits.

Link: https://lore.kernel.org/linux-pci/20240327-pci-dbi-rework-v12-7-082625472414@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
---
 drivers/pci/controller/dwc/pci-dra7xx.c       |  7 ++++++
 drivers/pci/controller/dwc/pci-imx6.c         |  8 +++++++
 drivers/pci/controller/dwc/pci-keystone.c     |  9 ++++++++
 .../pci/controller/dwc/pci-layerscape-ep.c    |  7 ++++++
 drivers/pci/controller/dwc/pcie-artpec6.c     | 13 ++++++++++-
 .../pci/controller/dwc/pcie-designware-ep.c   | 22 -------------------
 .../pci/controller/dwc/pcie-designware-plat.c |  9 ++++++++
 drivers/pci/controller/dwc/pcie-keembay.c     | 16 +++++++++++++-
 drivers/pci/controller/dwc/pcie-rcar-gen4.c   | 12 +++++++++-
 drivers/pci/controller/dwc/pcie-uniphier-ep.c | 13 ++++++++++-
 10 files changed, 90 insertions(+), 26 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-dra7xx.c b/drivers/pci/controller/dwc/pci-dra7xx.c
index 0e406677060d..395042b29ffc 100644
--- a/drivers/pci/controller/dwc/pci-dra7xx.c
+++ b/drivers/pci/controller/dwc/pci-dra7xx.c
@@ -467,6 +467,13 @@ static int dra7xx_add_pcie_ep(struct dra7xx_pcie *dra7xx,
 		return ret;
 	}
 
+	ret = dw_pcie_ep_init_registers(ep);
+	if (ret) {
+		dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+		dw_pcie_ep_deinit(ep);
+		return ret;
+	}
+
 	return 0;
 }
 
diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 99a60270b26c..8d28ecc381bc 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -1123,6 +1123,14 @@ static int imx6_add_pcie_ep(struct imx6_pcie *imx6_pcie,
 		dev_err(dev, "failed to initialize endpoint\n");
 		return ret;
 	}
+
+	ret = dw_pcie_ep_init_registers(ep);
+	if (ret) {
+		dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+		dw_pcie_ep_deinit(ep);
+		return ret;
+	}
+
 	/* Start LTSSM. */
 	imx6_pcie_ltssm_enable(dev);
 
diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c
index 844de4418724..81ebac520650 100644
--- a/drivers/pci/controller/dwc/pci-keystone.c
+++ b/drivers/pci/controller/dwc/pci-keystone.c
@@ -1286,6 +1286,13 @@ static int ks_pcie_probe(struct platform_device *pdev)
 		ret = dw_pcie_ep_init(&pci->ep);
 		if (ret < 0)
 			goto err_get_sync;
+
+		ret = dw_pcie_ep_init_registers(&pci->ep);
+		if (ret) {
+			dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+			goto err_ep_init;
+		}
+
 		break;
 	default:
 		dev_err(dev, "INVALID device type %d\n", mode);
@@ -1295,6 +1302,8 @@ static int ks_pcie_probe(struct platform_device *pdev)
 
 	return 0;
 
+err_ep_init:
+	dw_pcie_ep_deinit(&pci->ep);
 err_get_sync:
 	pm_runtime_put(dev);
 	pm_runtime_disable(dev);
diff --git a/drivers/pci/controller/dwc/pci-layerscape-ep.c b/drivers/pci/controller/dwc/pci-layerscape-ep.c
index 1f6ee1460ec2..9eb2233e3d7f 100644
--- a/drivers/pci/controller/dwc/pci-layerscape-ep.c
+++ b/drivers/pci/controller/dwc/pci-layerscape-ep.c
@@ -279,6 +279,13 @@ static int __init ls_pcie_ep_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
+	ret = dw_pcie_ep_init_registers(&pci->ep);
+	if (ret) {
+		dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+		dw_pcie_ep_deinit(&pci->ep);
+		return ret;
+	}
+
 	return ls_pcie_ep_interrupt_init(pcie, pdev);
 }
 
diff --git a/drivers/pci/controller/dwc/pcie-artpec6.c b/drivers/pci/controller/dwc/pcie-artpec6.c
index 9ed0a9ba7619..a6095561db4a 100644
--- a/drivers/pci/controller/dwc/pcie-artpec6.c
+++ b/drivers/pci/controller/dwc/pcie-artpec6.c
@@ -441,7 +441,18 @@ static int artpec6_pcie_probe(struct platform_device *pdev)
 
 		pci->ep.ops = &pcie_ep_ops;
 
-		return dw_pcie_ep_init(&pci->ep);
+		ret = dw_pcie_ep_init(&pci->ep);
+		if (ret)
+			return ret;
+
+		ret = dw_pcie_ep_init_registers(&pci->ep);
+		if (ret) {
+			dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+			dw_pcie_ep_deinit(&pci->ep);
+			return ret;
+		}
+
+		break;
 	default:
 		dev_err(dev, "INVALID device type %d\n", artpec6_pcie->mode);
 	}
diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index 761d3012a073..2063cf2049e5 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -821,7 +821,6 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 	struct device *dev = pci->dev;
 	struct platform_device *pdev = to_platform_device(dev);
 	struct device_node *np = dev->of_node;
-	const struct pci_epc_features *epc_features;
 
 	INIT_LIST_HEAD(&ep->func_list);
 
@@ -867,29 +866,8 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 		goto err_exit_epc_mem;
 	}
 
-	if (ep->ops->get_features) {
-		epc_features = ep->ops->get_features(ep);
-		if (epc_features->core_init_notifier)
-			return 0;
-	}
-
-	/*
-	 * NOTE:- Avoid accessing the hardware (Ex:- DBI space) before this
-	 * step as platforms that implement 'core_init_notifier' feature may
-	 * not have the hardware ready (i.e. core initialized) for access
-	 * (Ex: tegra194). Any hardware access on such platforms result
-	 * in system hang.
-	 */
-	ret = dw_pcie_ep_init_registers(ep);
-	if (ret)
-		goto err_free_epc_mem;
-
 	return 0;
 
-err_free_epc_mem:
-	pci_epc_mem_free_addr(epc, ep->msi_mem_phys, ep->msi_mem,
-			      epc->mem->window.page_size);
-
 err_exit_epc_mem:
 	pci_epc_mem_exit(epc);
 
diff --git a/drivers/pci/controller/dwc/pcie-designware-plat.c b/drivers/pci/controller/dwc/pcie-designware-plat.c
index 778588b4be70..ca9b22e654cd 100644
--- a/drivers/pci/controller/dwc/pcie-designware-plat.c
+++ b/drivers/pci/controller/dwc/pcie-designware-plat.c
@@ -145,6 +145,15 @@ static int dw_plat_pcie_probe(struct platform_device *pdev)
 
 		pci->ep.ops = &pcie_ep_ops;
 		ret = dw_pcie_ep_init(&pci->ep);
+		if (ret)
+			return ret;
+
+		ret = dw_pcie_ep_init_registers(&pci->ep);
+		if (ret) {
+			dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+			dw_pcie_ep_deinit(&pci->ep);
+		}
+
 		break;
 	default:
 		dev_err(dev, "INVALID device type %d\n", dw_plat_pcie->mode);
diff --git a/drivers/pci/controller/dwc/pcie-keembay.c b/drivers/pci/controller/dwc/pcie-keembay.c
index 5e8e54f597dd..b2556dbcffb5 100644
--- a/drivers/pci/controller/dwc/pcie-keembay.c
+++ b/drivers/pci/controller/dwc/pcie-keembay.c
@@ -396,6 +396,7 @@ static int keembay_pcie_probe(struct platform_device *pdev)
 	struct keembay_pcie *pcie;
 	struct dw_pcie *pci;
 	enum dw_pcie_device_mode mode;
+	int ret;
 
 	data = device_get_match_data(dev);
 	if (!data)
@@ -430,11 +431,24 @@ static int keembay_pcie_probe(struct platform_device *pdev)
 			return -ENODEV;
 
 		pci->ep.ops = &keembay_pcie_ep_ops;
-		return dw_pcie_ep_init(&pci->ep);
+		ret = dw_pcie_ep_init(&pci->ep);
+		if (ret)
+			return ret;
+
+		ret = dw_pcie_ep_init_registers(&pci->ep);
+		if (ret) {
+			dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+			dw_pcie_ep_deinit(&pci->ep);
+			return ret;
+		}
+
+		break;
 	default:
 		dev_err(dev, "Invalid device type %d\n", pcie->mode);
 		return -ENODEV;
 	}
+
+	return 0;
 }
 
 static const struct keembay_pcie_of_data keembay_pcie_rc_of_data = {
diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
index de4bdfaecab3..e155a905fb4f 100644
--- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
+++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
@@ -416,6 +416,7 @@ static const struct dw_pcie_ep_ops pcie_ep_ops = {
 static int rcar_gen4_add_dw_pcie_ep(struct rcar_gen4_pcie *rcar)
 {
 	struct dw_pcie_ep *ep = &rcar->dw.ep;
+	struct device *dev = rcar->dw.dev;
 	int ret;
 
 	if (!IS_ENABLED(CONFIG_PCIE_RCAR_GEN4_EP))
@@ -424,8 +425,17 @@ static int rcar_gen4_add_dw_pcie_ep(struct rcar_gen4_pcie *rcar)
 	ep->ops = &pcie_ep_ops;
 
 	ret = dw_pcie_ep_init(ep);
-	if (ret)
+	if (ret) {
 		rcar_gen4_pcie_ep_deinit(rcar);
+		return ret;
+	}
+
+	ret = dw_pcie_ep_init_registers(ep);
+	if (ret) {
+		dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+		dw_pcie_ep_deinit(ep);
+		rcar_gen4_pcie_ep_deinit(rcar);
+	}
 
 	return ret;
 }
diff --git a/drivers/pci/controller/dwc/pcie-uniphier-ep.c b/drivers/pci/controller/dwc/pcie-uniphier-ep.c
index 639bc2e12476..0e5e7344de48 100644
--- a/drivers/pci/controller/dwc/pcie-uniphier-ep.c
+++ b/drivers/pci/controller/dwc/pcie-uniphier-ep.c
@@ -399,7 +399,18 @@ static int uniphier_pcie_ep_probe(struct platform_device *pdev)
 		return ret;
 
 	priv->pci.ep.ops = &uniphier_pcie_ep_ops;
-	return dw_pcie_ep_init(&priv->pci.ep);
+	ret = dw_pcie_ep_init(&priv->pci.ep);
+	if (ret)
+		return ret;
+
+	ret = dw_pcie_ep_init_registers(&priv->pci.ep);
+	if (ret) {
+		dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+		dw_pcie_ep_deinit(&priv->pci.ep);
+		return ret;
+	}
+
+	return 0;
 }
 
 static const struct uniphier_pcie_ep_soc_data uniphier_pro5_data = {

From a01e7214bef904723d26d293eb17586078610379 Mon Sep 17 00:00:00 2001
From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Date: Wed, 27 Mar 2024 14:43:37 +0530
Subject: [PATCH 8/8] PCI: endpoint: Remove "core_init_notifier" flag
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

"core_init_notifier" flag is set by the glue drivers requiring refclk from
the host to complete the DWC core initialization. Also, those drivers will
send a notification to the EPF drivers once the initialization is fully
completed using the pci_epc_init_notify() API. Only then, the EPF drivers
will start functioning.

For the rest of the drivers generating refclk locally, EPF drivers will
start functioning post binding with them. EPF drivers rely on the
'core_init_notifier' flag to differentiate between the drivers.
Unfortunately, this creates two different flows for the EPF drivers.

So to avoid that, let's get rid of the "core_init_notifier" flag and follow
a single initialization flow for the EPF drivers. This is done by calling
the dw_pcie_ep_init_notify() from all glue drivers after the completion of
dw_pcie_ep_init_registers() API. This will allow all the glue drivers to
send the notification to the EPF drivers once the initialization is fully
completed.

Only difference here is that, the drivers requiring refclk from host will
send the notification once refclk is received, while others will send it
during probe time itself.

But this also requires the EPC core driver to deliver the notification
after EPF driver bind. Because, the glue driver can send the notification
before the EPF drivers bind() and in those cases the EPF drivers will miss
the event. To accommodate this, EPC core is now caching the state of the
EPC initialization in 'init_complete' flag and pci-ep-cfs driver sends the
notification to EPF drivers based on that after each EPF driver bind.

Link: https://lore.kernel.org/linux-pci/20240327-pci-dbi-rework-v12-8-082625472414@linaro.org
Tested-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
---
 .../pci/controller/cadence/pcie-cadence-ep.c  |  2 ++
 drivers/pci/controller/dwc/pci-dra7xx.c       |  2 ++
 drivers/pci/controller/dwc/pci-imx6.c         |  2 ++
 drivers/pci/controller/dwc/pci-keystone.c     |  2 ++
 .../pci/controller/dwc/pci-layerscape-ep.c    |  2 ++
 drivers/pci/controller/dwc/pcie-artpec6.c     |  2 ++
 .../pci/controller/dwc/pcie-designware-ep.c   |  1 +
 .../pci/controller/dwc/pcie-designware-plat.c |  2 ++
 drivers/pci/controller/dwc/pcie-keembay.c     |  2 ++
 drivers/pci/controller/dwc/pcie-qcom-ep.c     |  1 -
 drivers/pci/controller/dwc/pcie-rcar-gen4.c   |  2 ++
 drivers/pci/controller/dwc/pcie-tegra194.c    |  1 -
 drivers/pci/controller/dwc/pcie-uniphier-ep.c |  2 ++
 drivers/pci/controller/pcie-rcar-ep.c         |  2 ++
 drivers/pci/controller/pcie-rockchip-ep.c     |  2 ++
 drivers/pci/endpoint/functions/pci-epf-test.c | 18 +++++----------
 drivers/pci/endpoint/pci-ep-cfs.c             |  9 ++++++++
 drivers/pci/endpoint/pci-epc-core.c           | 22 +++++++++++++++++++
 include/linux/pci-epc.h                       |  7 +++---
 19 files changed, 65 insertions(+), 18 deletions(-)

diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c
index 81c50dc64da9..55c42ca2b777 100644
--- a/drivers/pci/controller/cadence/pcie-cadence-ep.c
+++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c
@@ -746,6 +746,8 @@ int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep)
 
 	spin_lock_init(&ep->lock);
 
+	pci_epc_init_notify(epc);
+
 	return 0;
 
  free_epc_mem:
diff --git a/drivers/pci/controller/dwc/pci-dra7xx.c b/drivers/pci/controller/dwc/pci-dra7xx.c
index 395042b29ffc..d2d17d37d3e0 100644
--- a/drivers/pci/controller/dwc/pci-dra7xx.c
+++ b/drivers/pci/controller/dwc/pci-dra7xx.c
@@ -474,6 +474,8 @@ static int dra7xx_add_pcie_ep(struct dra7xx_pcie *dra7xx,
 		return ret;
 	}
 
+	dw_pcie_ep_init_notify(ep);
+
 	return 0;
 }
 
diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 8d28ecc381bc..917c69edee1d 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -1131,6 +1131,8 @@ static int imx6_add_pcie_ep(struct imx6_pcie *imx6_pcie,
 		return ret;
 	}
 
+	dw_pcie_ep_init_notify(ep);
+
 	/* Start LTSSM. */
 	imx6_pcie_ltssm_enable(dev);
 
diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c
index 81ebac520650..d3a7d14ee685 100644
--- a/drivers/pci/controller/dwc/pci-keystone.c
+++ b/drivers/pci/controller/dwc/pci-keystone.c
@@ -1293,6 +1293,8 @@ static int ks_pcie_probe(struct platform_device *pdev)
 			goto err_ep_init;
 		}
 
+		dw_pcie_ep_init_notify(&pci->ep);
+
 		break;
 	default:
 		dev_err(dev, "INVALID device type %d\n", mode);
diff --git a/drivers/pci/controller/dwc/pci-layerscape-ep.c b/drivers/pci/controller/dwc/pci-layerscape-ep.c
index 9eb2233e3d7f..7dde6d5fa4d8 100644
--- a/drivers/pci/controller/dwc/pci-layerscape-ep.c
+++ b/drivers/pci/controller/dwc/pci-layerscape-ep.c
@@ -286,6 +286,8 @@ static int __init ls_pcie_ep_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	dw_pcie_ep_init_notify(&pci->ep);
+
 	return ls_pcie_ep_interrupt_init(pcie, pdev);
 }
 
diff --git a/drivers/pci/controller/dwc/pcie-artpec6.c b/drivers/pci/controller/dwc/pcie-artpec6.c
index a6095561db4a..a4630b92489b 100644
--- a/drivers/pci/controller/dwc/pcie-artpec6.c
+++ b/drivers/pci/controller/dwc/pcie-artpec6.c
@@ -452,6 +452,8 @@ static int artpec6_pcie_probe(struct platform_device *pdev)
 			return ret;
 		}
 
+		dw_pcie_ep_init_notify(&pci->ep);
+
 		break;
 	default:
 		dev_err(dev, "INVALID device type %d\n", artpec6_pcie->mode);
diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index 2063cf2049e5..47391d7d3a73 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -632,6 +632,7 @@ void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep)
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
 
 	dw_pcie_edma_remove(pci);
+	ep->epc->init_complete = false;
 }
 EXPORT_SYMBOL_GPL(dw_pcie_ep_cleanup);
 
diff --git a/drivers/pci/controller/dwc/pcie-designware-plat.c b/drivers/pci/controller/dwc/pcie-designware-plat.c
index ca9b22e654cd..8490c5d6ff9f 100644
--- a/drivers/pci/controller/dwc/pcie-designware-plat.c
+++ b/drivers/pci/controller/dwc/pcie-designware-plat.c
@@ -154,6 +154,8 @@ static int dw_plat_pcie_probe(struct platform_device *pdev)
 			dw_pcie_ep_deinit(&pci->ep);
 		}
 
+		dw_pcie_ep_init_notify(&pci->ep);
+
 		break;
 	default:
 		dev_err(dev, "INVALID device type %d\n", dw_plat_pcie->mode);
diff --git a/drivers/pci/controller/dwc/pcie-keembay.c b/drivers/pci/controller/dwc/pcie-keembay.c
index b2556dbcffb5..98bbc83182b4 100644
--- a/drivers/pci/controller/dwc/pcie-keembay.c
+++ b/drivers/pci/controller/dwc/pcie-keembay.c
@@ -442,6 +442,8 @@ static int keembay_pcie_probe(struct platform_device *pdev)
 			return ret;
 		}
 
+		dw_pcie_ep_init_notify(&pci->ep);
+
 		break;
 	default:
 		dev_err(dev, "Invalid device type %d\n", pcie->mode);
diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c
index 3697b4a944cc..2fb8c15e7a91 100644
--- a/drivers/pci/controller/dwc/pcie-qcom-ep.c
+++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c
@@ -775,7 +775,6 @@ static void qcom_pcie_ep_init_debugfs(struct qcom_pcie_ep *pcie_ep)
 
 static const struct pci_epc_features qcom_pcie_epc_features = {
 	.linkup_notifier = true,
-	.core_init_notifier = true,
 	.msi_capable = true,
 	.msix_capable = false,
 	.align = SZ_4K,
diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
index e155a905fb4f..cfeccc2f9ee1 100644
--- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
+++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
@@ -437,6 +437,8 @@ static int rcar_gen4_add_dw_pcie_ep(struct rcar_gen4_pcie *rcar)
 		rcar_gen4_pcie_ep_deinit(rcar);
 	}
 
+	dw_pcie_ep_init_notify(ep);
+
 	return ret;
 }
 
diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index db043f579fbe..ddc23602eca7 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -2006,7 +2006,6 @@ static int tegra_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
 
 static const struct pci_epc_features tegra_pcie_epc_features = {
 	.linkup_notifier = true,
-	.core_init_notifier = true,
 	.msi_capable = false,
 	.msix_capable = false,
 	.bar[BAR_0] = { .type = BAR_FIXED, .fixed_size = SZ_1M,
diff --git a/drivers/pci/controller/dwc/pcie-uniphier-ep.c b/drivers/pci/controller/dwc/pcie-uniphier-ep.c
index 0e5e7344de48..a2b844268e28 100644
--- a/drivers/pci/controller/dwc/pcie-uniphier-ep.c
+++ b/drivers/pci/controller/dwc/pcie-uniphier-ep.c
@@ -410,6 +410,8 @@ static int uniphier_pcie_ep_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	dw_pcie_ep_init_notify(&priv->pci.ep);
+
 	return 0;
 }
 
diff --git a/drivers/pci/controller/pcie-rcar-ep.c b/drivers/pci/controller/pcie-rcar-ep.c
index 05967c6c0b42..047e2cef5afc 100644
--- a/drivers/pci/controller/pcie-rcar-ep.c
+++ b/drivers/pci/controller/pcie-rcar-ep.c
@@ -542,6 +542,8 @@ static int rcar_pcie_ep_probe(struct platform_device *pdev)
 		goto err_pm_put;
 	}
 
+	pci_epc_init_notify(epc);
+
 	return 0;
 
 err_pm_put:
diff --git a/drivers/pci/controller/pcie-rockchip-ep.c b/drivers/pci/controller/pcie-rockchip-ep.c
index c9046e97a1d2..8613df8184df 100644
--- a/drivers/pci/controller/pcie-rockchip-ep.c
+++ b/drivers/pci/controller/pcie-rockchip-ep.c
@@ -609,6 +609,8 @@ static int rockchip_pcie_ep_probe(struct platform_device *pdev)
 	rockchip_pcie_write(rockchip, PCIE_CLIENT_CONF_ENABLE,
 			    PCIE_CLIENT_CONFIG);
 
+	pci_epc_init_notify(epc);
+
 	return 0;
 err_epc_mem_exit:
 	pci_epc_mem_exit(epc);
diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
index cd4ffb39dcdc..212fc303fb63 100644
--- a/drivers/pci/endpoint/functions/pci-epf-test.c
+++ b/drivers/pci/endpoint/functions/pci-epf-test.c
@@ -753,6 +753,7 @@ static int pci_epf_test_core_init(struct pci_epf *epf)
 	const struct pci_epc_features *epc_features;
 	struct pci_epc *epc = epf->epc;
 	struct device *dev = &epf->dev;
+	bool linkup_notifier = false;
 	bool msix_capable = false;
 	bool msi_capable = true;
 	int ret;
@@ -795,6 +796,10 @@ static int pci_epf_test_core_init(struct pci_epf *epf)
 		}
 	}
 
+	linkup_notifier = epc_features->linkup_notifier;
+	if (!linkup_notifier)
+		queue_work(kpcitest_workqueue, &epf_test->cmd_handler.work);
+
 	return 0;
 }
 
@@ -890,8 +895,6 @@ static int pci_epf_test_bind(struct pci_epf *epf)
 	const struct pci_epc_features *epc_features;
 	enum pci_barno test_reg_bar = BAR_0;
 	struct pci_epc *epc = epf->epc;
-	bool linkup_notifier = false;
-	bool core_init_notifier = false;
 
 	if (WARN_ON_ONCE(!epc))
 		return -EINVAL;
@@ -902,8 +905,6 @@ static int pci_epf_test_bind(struct pci_epf *epf)
 		return -EOPNOTSUPP;
 	}
 
-	linkup_notifier = epc_features->linkup_notifier;
-	core_init_notifier = epc_features->core_init_notifier;
 	test_reg_bar = pci_epc_get_first_free_bar(epc_features);
 	if (test_reg_bar < 0)
 		return -EINVAL;
@@ -916,21 +917,12 @@ static int pci_epf_test_bind(struct pci_epf *epf)
 	if (ret)
 		return ret;
 
-	if (!core_init_notifier) {
-		ret = pci_epf_test_core_init(epf);
-		if (ret)
-			return ret;
-	}
-
 	epf_test->dma_supported = true;
 
 	ret = pci_epf_test_init_dma_chan(epf_test);
 	if (ret)
 		epf_test->dma_supported = false;
 
-	if (!linkup_notifier && !core_init_notifier)
-		queue_work(kpcitest_workqueue, &epf_test->cmd_handler.work);
-
 	return 0;
 }
 
diff --git a/drivers/pci/endpoint/pci-ep-cfs.c b/drivers/pci/endpoint/pci-ep-cfs.c
index 0ea64e24ed61..3b21e28f9b59 100644
--- a/drivers/pci/endpoint/pci-ep-cfs.c
+++ b/drivers/pci/endpoint/pci-ep-cfs.c
@@ -64,6 +64,9 @@ static int pci_secondary_epc_epf_link(struct config_item *epf_item,
 		return ret;
 	}
 
+	/* Send any pending EPC initialization complete to the EPF driver */
+	pci_epc_notify_pending_init(epc, epf);
+
 	return 0;
 }
 
@@ -125,6 +128,9 @@ static int pci_primary_epc_epf_link(struct config_item *epf_item,
 		return ret;
 	}
 
+	/* Send any pending EPC initialization complete to the EPF driver */
+	pci_epc_notify_pending_init(epc, epf);
+
 	return 0;
 }
 
@@ -230,6 +236,9 @@ static int pci_epc_epf_link(struct config_item *epc_item,
 		return ret;
 	}
 
+	/* Send any pending EPC initialization complete to the EPF driver */
+	pci_epc_notify_pending_init(epc, epf);
+
 	return 0;
 }
 
diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
index da3fc0795b0b..47d27ec7439d 100644
--- a/drivers/pci/endpoint/pci-epc-core.c
+++ b/drivers/pci/endpoint/pci-epc-core.c
@@ -748,10 +748,32 @@ void pci_epc_init_notify(struct pci_epc *epc)
 			epf->event_ops->core_init(epf);
 		mutex_unlock(&epf->lock);
 	}
+	epc->init_complete = true;
 	mutex_unlock(&epc->list_lock);
 }
 EXPORT_SYMBOL_GPL(pci_epc_init_notify);
 
+/**
+ * pci_epc_notify_pending_init() - Notify the pending EPC device initialization
+ *                                 complete to the EPF device
+ * @epc: the EPC device whose core initialization is pending to be notified
+ * @epf: the EPF device to be notified
+ *
+ * Invoke to notify the pending EPC device initialization complete to the EPF
+ * device. This is used to deliver the notification if the EPC initialization
+ * got completed before the EPF driver bind.
+ */
+void pci_epc_notify_pending_init(struct pci_epc *epc, struct pci_epf *epf)
+{
+	if (epc->init_complete) {
+		mutex_lock(&epf->lock);
+		if (epf->event_ops && epf->event_ops->core_init)
+			epf->event_ops->core_init(epf);
+		mutex_unlock(&epf->lock);
+	}
+}
+EXPORT_SYMBOL_GPL(pci_epc_notify_pending_init);
+
 /**
  * pci_epc_bme_notify() - Notify the EPF device that the EPC device has received
  *			  the BME event from the Root complex
diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
index cc2f70d061c8..acc5f96161fe 100644
--- a/include/linux/pci-epc.h
+++ b/include/linux/pci-epc.h
@@ -128,6 +128,8 @@ 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
+ * @init_complete: flag to indicate whether the EPC initialization is complete
+ *                 or not
  */
 struct pci_epc {
 	struct device			dev;
@@ -143,6 +145,7 @@ struct pci_epc {
 	/* mutex to protect against concurrent access of EP controller */
 	struct mutex			lock;
 	unsigned long			function_num_map;
+	bool				init_complete;
 };
 
 /**
@@ -179,8 +182,6 @@ struct pci_epc_bar_desc {
 /**
  * struct pci_epc_features - features supported by a EPC device per function
  * @linkup_notifier: indicate if the EPC device can notify EPF driver on link up
- * @core_init_notifier: indicate cores that can notify about their availability
- *			for initialization
  * @msi_capable: indicate if the endpoint function has MSI capability
  * @msix_capable: indicate if the endpoint function has MSI-X capability
  * @bar: array specifying the hardware description for each BAR
@@ -188,7 +189,6 @@ struct pci_epc_bar_desc {
  */
 struct pci_epc_features {
 	unsigned int	linkup_notifier : 1;
-	unsigned int	core_init_notifier : 1;
 	unsigned int	msi_capable : 1;
 	unsigned int	msix_capable : 1;
 	struct	pci_epc_bar_desc bar[PCI_STD_NUM_BARS];
@@ -225,6 +225,7 @@ int pci_epc_add_epf(struct pci_epc *epc, struct pci_epf *epf,
 void pci_epc_linkup(struct pci_epc *epc);
 void pci_epc_linkdown(struct pci_epc *epc);
 void pci_epc_init_notify(struct pci_epc *epc);
+void pci_epc_notify_pending_init(struct pci_epc *epc, struct pci_epf *epf);
 void pci_epc_bme_notify(struct pci_epc *epc);
 void pci_epc_remove_epf(struct pci_epc *epc, struct pci_epf *epf,
 			enum pci_epc_interface_type type);