PCI: imx6: Add speed change timeout message

Currently, the timeout is never detected as count has a value of -1 if a
timeout happens, but the code is checking for 0.  Also, this patch removes
the unneeded final wait if a timeout occurs.

[bhelgaas: reworked starting from http://lkml.kernel.org/r/1433543864-7252-1-git-send-email-troy.kisky@boundarydevices.com]
Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
index fdb95367721e9b2e9758ee9f05beb4c878374dbd..c93bcdf58a56b2ff8bd80612661fa45a625c5d22 100644 (file)
--- a/drivers/pci/host/pci-imx6.c
+++ b/drivers/pci/host/pci-imx6.c
@@ -352,6 +352,23 @@ static int imx6_pcie_wait_for_link(struct pcie_port *pp)
        return 0;
 }
 
+static int imx6_pcie_wait_for_speed_change(struct pcie_port *pp)
+{
+       uint32_t tmp;
+       unsigned int retries;
+
+       for (retries = 0; retries < 200; retries++) {
+               tmp = readl(pp->dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
+               /* Test if the speed change finished. */
+               if (!(tmp & PORT_LOGIC_SPEED_CHANGE))
+                       return 0;
+               usleep_range(100, 1000);
+       }
+
+       dev_err(pp->dev, "Speed change timeout\n");
+       return -EINVAL;
+}
+
 static irqreturn_t imx6_pcie_msi_handler(int irq, void *arg)
 {
        struct pcie_port *pp = arg;
@@ -363,7 +380,7 @@ static int imx6_pcie_start_link(struct pcie_port *pp)
 {
        struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
        uint32_t tmp;
-       int ret, count;
+       int ret;
 
        /*
         * Force Gen1 operation when starting the link.  In case the link is
@@ -397,29 +414,22 @@ static int imx6_pcie_start_link(struct pcie_port *pp)
        tmp |= PORT_LOGIC_SPEED_CHANGE;
        writel(tmp, pp->dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
 
-       count = 200;
-       while (count--) {
-               tmp = readl(pp->dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
-               /* Test if the speed change finished. */
-               if (!(tmp & PORT_LOGIC_SPEED_CHANGE))
-                       break;
-               usleep_range(100, 1000);
+       ret = imx6_pcie_wait_for_speed_change(pp);
+       if (ret) {
+               dev_err(pp->dev, "Failed to bring link up!\n");
+               return ret;
        }
 
        /* Make sure link training is finished as well! */
-       if (count)
-               ret = imx6_pcie_wait_for_link(pp);
-       else
-               ret = -EINVAL;
-
+       ret = imx6_pcie_wait_for_link(pp);
        if (ret) {
                dev_err(pp->dev, "Failed to bring link up!\n");
-       } else {
-               tmp = readl(pp->dbi_base + 0x80);
-               dev_dbg(pp->dev, "Link up, Gen=%i\n", (tmp >> 16) & 0xf);
+               return ret;
        }
 
-       return ret;
+       tmp = readl(pp->dbi_base + 0x80);
+       dev_dbg(pp->dev, "Link up, Gen=%i\n", (tmp >> 16) & 0xf);
+       return 0;
 }
 
 static void imx6_pcie_host_init(struct pcie_port *pp)