[PATCH 2/3] pci: pcie-rcar-gen4: Avoid repeated link attempts

Avoid repeated link attempts for these controllers. In case the
controller link is up, this is a noop since the probe() already
finished. In case the controller link is down, a repeated link
up attempt seems to require reset of both PCIe controllers, which
is not desired. It is also unlikely that a repeated link attempt
would bring the link up, as U-Boot does not support hotplug anyway.
Therefore, prevent repeated link attempts.

Signed-off-by: Marek Vasut <[email protected]>
---
Cc: Nobuhiro Iwamatsu <[email protected]>
Cc: Tom Rini <[email protected]>
Cc: [email protected]
---
 drivers/pci/pci-rcar-gen4.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/pci/pci-rcar-gen4.c b/drivers/pci/pci-rcar-gen4.c
index 34561406641..044bceee6c7 100644
--- a/drivers/pci/pci-rcar-gen4.c
+++ b/drivers/pci/pci-rcar-gen4.c
@@ -112,6 +112,15 @@ struct rcar_gen4_pcie {
 	size_t			firmware_size;
 };
 
+/**
+ * struct rcar_gen4_pcie_plat - Renesas R-Car Gen4 DW PCIe controller platform data
+ *
+ * @probed: Controller was started
+ */
+struct rcar_gen4_pcie_plat {
+	bool			probed;
+};
+
 /* Common */
 static bool rcar_gen4_pcie_link_up(struct rcar_gen4_pcie *rcar)
 {
@@ -404,10 +413,14 @@ static int rcar_gen4_pcie_load_firmware(struct rcar_gen4_pcie *rcar)
 static int rcar_gen4_pcie_probe(struct udevice *dev)
 {
 	struct rcar_gen4_pcie *rcar = dev_get_priv(dev);
+	struct rcar_gen4_pcie_plat *plat = dev_get_plat(dev);
 	struct udevice *ctlr = pci_get_controller(dev);
 	struct pci_controller *hose = dev_get_uclass_priv(ctlr);
 	int ret;
 
+	if (plat->probed)
+		return -ENODEV;
+
 	ret = rcar_gen4_pcie_load_firmware(rcar);
 	if (ret)
 		return ret;
@@ -447,6 +460,7 @@ static int rcar_gen4_pcie_probe(struct udevice *dev)
 	dw_pcie_link_set_max_link_width(&rcar->dw, rcar->num_lanes);
 
 	ret = rcar_gen4_pcie_start_link(rcar);
+	plat->probed = true;
 	if (ret)
 		return ret;
 
@@ -569,5 +583,6 @@ U_BOOT_DRIVER(rcar_gen4_pcie) = {
 	.probe		= rcar_gen4_pcie_probe,
 	.remove		= rcar_gen4_pcie_remove,
 	.priv_auto	= sizeof(struct rcar_gen4_pcie),
+	.plat_auto	= sizeof(struct rcar_gen4_pcie_plat),
 	.flags		= DM_FLAG_ACTIVE_DMA,
 };
-- 
2.53.0