PCI: dwc: Move iATU detection earlier

dw_pcie_ep_init() depends on the detected iATU region numbers to allocate
the in/outbound window management bitmap. It fails after 281f1f99cf3a
("PCI: dwc: Detect number of iATU windows").

Move the iATU region detection into a new function, move the detection to
the very beginning of dw_pcie_host_init() and dw_pcie_ep_init(). Also
remove it from the dw_pcie_setup(), since it's more like a software
initialization step than hardware setup.

Link: https://lore.kernel.org/r/[e-mail]
Link: https://lore.kernel.org/linux-pci/[e-mail]
Link: https://lore.kernel.org/r/[e-mail]
Fixes: 281f1f99cf3a ("PCI: dwc: Detect number of iATU windows")
Tested-by: Kunihiko Hayashi <[e-mail]>
Tested-by: Marek Szyprowski <[e-mail]>
Tested-by: Manivannan Sadhasivam <[e-mail]>
Signed-off-by: Hou Zhiqiang <[e-mail]>
[DB: moved dw_pcie_iatu_detect to happen after host_init callback]
Signed-off-by: Dmitry Baryshkov <[e-mail]>
Signed-off-by: Lorenzo Pieralisi <[e-mail]>
Reviewed-by: Rob Herring <[e-mail]>
Cc: [e-mail] # v5.11+
Cc: Marek Szyprowski <[e-mail]>

drivers/pci/controller/dwc/pcie-designware-ep.c

···
 		}
 	}
 
+	dw_pcie_iatu_detect(pci);
+
 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "addr_space");
 	if (!res)
 		return -EINVAL;

drivers/pci/controller/dwc/pcie-designware-host.c

···
 		if (ret)
 			goto err_free_msi;
 	}
+	dw_pcie_iatu_detect(pci);
 
 	dw_pcie_setup_rc(pp);
 

drivers/pci/controller/dwc/pcie-designware.c

···
 	pci->num_ob_windows = ob;
 }
 
-void dw_pcie_setup(struct dw_pcie *pci)
+void dw_pcie_iatu_detect(struct dw_pcie *pci)
 {
-	u32 val;
 	struct device *dev = pci->dev;
-	struct device_node *np = dev->of_node;
 	struct platform_device *pdev = to_platform_device(dev);
 
 	if (pci->version >= 0x480A || (!pci->version &&
···
 
 	dev_info(pci->dev, "Detected iATU regions: %u outbound, %u inbound",
 		 pci->num_ob_windows, pci->num_ib_windows);
+}
+
+void dw_pcie_setup(struct dw_pcie *pci)
+{
+	u32 val;
+	struct device *dev = pci->dev;
+	struct device_node *np = dev->of_node;
 
 	if (pci->link_gen > 0)
 		dw_pcie_link_set_max_speed(pci, pci->link_gen);

drivers/pci/controller/dwc/pcie-designware.h

···
 void dw_pcie_disable_atu(struct dw_pcie *pci, int index,
 			 enum dw_pcie_region_type type);
 void dw_pcie_setup(struct dw_pcie *pci);
+void dw_pcie_iatu_detect(struct dw_pcie *pci);
 
 static inline void dw_pcie_writel_dbi(struct dw_pcie *pci, u32 reg, u32 val)
 {