pci: mediatek: add support for multiple ports in mediatek pcie gen3 driver

One MediaTek PCIe Gen3 controller has only one port, where PCI bus 0
on this port represents the controller itself and bus 1 represents
the external PCIe device.

If multiple PCIe controllers are probed in U-Boot, U-Boot will use
bus numbers greater than 2 as input parameters. Therefore, we should
convert the BDF bus number to either 0 or 1 by subtracting the
offset by controller->seq_.

Signed-off-by: Sam Shih <sam.shih@mediatek.com>
Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>

diff --git a/drivers/pci/pcie_mediatek_gen3.c b/drivers/pci/pcie_mediatek_gen3.c
index 0149eda..1818d4c 100644 (file)
--- a/drivers/pci/pcie_mediatek_gen3.c
+++ b/drivers/pci/pcie_mediatek_gen3.c
@@ -83,6 +83,28 @@ struct mtk_pcie {
        struct phy phy;
 };
 
+static pci_dev_t convert_bdf(const struct udevice *controller, pci_dev_t bdf)
+{
+       int bdfs[3];
+
+       bdfs[0] = PCI_BUS(bdf);
+       bdfs[1] = PCI_DEV(bdf);
+       bdfs[2] = PCI_FUNC(bdf);
+
+       /*
+        * One MediaTek PCIe Gen3 controller has only one port, where PCI bus 0 on
+        * this port represents the controller itself and bus 1 represents the
+        * external PCIe device. If multiple PCIe controllers are probed in U-Boot,
+        * U-Boot will use bus numbers greater than 2 as input parameters. Therefore,
+        * we should convert the BDF bus number to either 0 or 1 by subtracting the
+        * offset by controller->seq_
+        */
+
+       bdfs[0] = bdfs[0] - controller->seq_;
+
+       return PCI_BDF(bdfs[0], bdfs[1], bdfs[2]);
+}
+
 static void mtk_pcie_config_tlp_header(const struct udevice *bus,
                                       pci_dev_t devfn,
                                       int where, int size)
@@ -91,6 +113,8 @@ static void mtk_pcie_config_tlp_header(const struct udevice *bus,
        int bytes;
        u32 val;
 
+       devfn = convert_bdf(bus, devfn);
+
        size = 1 << size;
        bytes = (GENMASK(size - 1, 0) & 0xf) << (where & 0x3);