PCI: dwc: Fix ATU identification for designware version >= 4.80

Synopsys designware version >= 4.80 uses a separate register space
for programming ATU. The current code identifies if there exists a
separate register space by accessing the register address of ATUs
in designware version < 4.80. Accessing this address results in
abort in the case of K2G.

Fix it here by adding "version" member to struct dw_pcie. This should be
set by platform specific drivers and designware core will use it to
identify if the platform has a separate ATU space. For platforms which
have not populated the version member, the old method of identification
will still be used.
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

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

@@ -358,13 +358,15 @@ void dw_pcie_setup(struct dw_pcie *pci)
 	struct device *dev = pci->dev;
 	struct device_node *np = dev->of_node;
 
-	/* Get iATU unroll support */
-	pci->iatu_unroll_enabled = dw_pcie_iatu_unroll_enabled(pci);
-	dev_dbg(pci->dev, "iATU unroll: %s\n",
-		pci->iatu_unroll_enabled ? "enabled" : "disabled");
-
-	if (pci->iatu_unroll_enabled && !pci->atu_base)
+	if (pci->version >= 0x480A || (!pci->version &&
+				       dw_pcie_iatu_unroll_enabled(pci))) {
+		pci->iatu_unroll_enabled = true;
+		if (!pci->atu_base)
 			pci->atu_base = pci->dbi_base + DEFAULT_DBI_ATU_OFFSET;
+	}
+	dev_dbg(pci->dev, "iATU unroll: %s\n", pci->iatu_unroll_enabled ?
+		"enabled" : "disabled");
+
 
 	ret = of_property_read_u32(np, "num-lanes", &lanes);
 	if (ret)

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

@@ -234,6 +234,7 @@ struct dw_pcie {
 	struct pcie_port	pp;
 	struct dw_pcie_ep	ep;
 	const struct dw_pcie_ops *ops;
+	unsigned int		version;
 };
 
 #define to_dw_pcie_from_pp(port) container_of((port), struct dw_pcie, pp)