From a0427464cf4c4ae80aaa16dbcefc39ba9a5e258b Mon Sep 17 00:00:00 2001 From: Troy Kisky Date: Fri, 12 Jun 2015 14:30:16 -0500 Subject: [PATCH] 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 Signed-off-by: Bjorn Helgaas --- drivers/pci/host/pci-imx6.c | 44 +++++++++++++++++++++++-------------- 1 file changed, 27 insertions(+), 17 deletions(-) diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c index fdb95367721e..c93bcdf58a56 100644 --- 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) -- 2.20.1