Merge tag 'pci-v5.17-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaa...

[uclinux-h8/linux.git] / drivers / pci / controller / pcie-apple.c

diff --git a/drivers/pci/controller/pcie-apple.c b/drivers/pci/controller/pcie-apple.c
index f985513..854d951 100644 (file)
--- a/drivers/pci/controller/pcie-apple.c
+++ b/drivers/pci/controller/pcie-apple.c
@@ -517,7 +517,7 @@ static int apple_pcie_setup_port(struct apple_pcie *pcie,
        int ret, i;
 
        reset = gpiod_get_from_of_node(np, "reset-gpios", 0,
-                                      GPIOD_OUT_LOW, "#PERST");
+                                      GPIOD_OUT_LOW, "PERST#");
        if (IS_ERR(reset))
                return PTR_ERR(reset);
 
@@ -540,12 +540,22 @@ static int apple_pcie_setup_port(struct apple_pcie *pcie,
 
        rmw_set(PORT_APPCLK_EN, port->base + PORT_APPCLK);
 
+       /* Assert PERST# before setting up the clock */
+       gpiod_set_value(reset, 1);
+
        ret = apple_pcie_setup_refclk(pcie, port);
        if (ret < 0)
                return ret;
 
+       /* The minimal Tperst-clk value is 100us (PCIe CEM r5.0, 2.9.2) */
+       usleep_range(100, 200);
+
+       /* Deassert PERST# */
        rmw_set(PORT_PERST_OFF, port->base + PORT_PERST);
-       gpiod_set_value(reset, 1);
+       gpiod_set_value(reset, 0);
+
+       /* Wait for 100ms after PERST# deassertion (PCIe r5.0, 6.6.1) */
+       msleep(100);
 
        ret = readl_relaxed_poll_timeout(port->base + PORT_STATUS, stat,
                                         stat & PORT_STATUS_READY, 100, 250000);