From e10b7a184ccf883a456c8683fa2e53eddd3aeb9c Mon Sep 17 00:00:00 2001 From: Ryder Lee Date: Thu, 10 Aug 2017 14:34:54 +0800 Subject: [PATCH] PCI: mediatek: Use readl_poll_timeout() to wait for Gen2 training Wait for Gen2 training with readl_poll_timeout(), and simplify the hardware assert logical by merging it into a new mtk_pcie_startup_port() interface. Signed-off-by: Ryder Lee Signed-off-by: Honghui Zhang Signed-off-by: Bjorn Helgaas --- drivers/pci/host/pcie-mediatek.c | 52 ++++++++++++++------------------ 1 file changed, 22 insertions(+), 30 deletions(-) diff --git a/drivers/pci/host/pcie-mediatek.c b/drivers/pci/host/pcie-mediatek.c index 9c9f89bcf24c..f4e42266eaa7 100644 --- a/drivers/pci/host/pcie-mediatek.c +++ b/drivers/pci/host/pcie-mediatek.c @@ -16,6 +16,7 @@ #include #include +#include #include #include #include @@ -113,11 +114,6 @@ struct mtk_pcie { struct list_head ports; }; -static inline bool mtk_pcie_link_up(struct mtk_pcie_port *port) -{ - return !!(readl(port->base + PCIE_LINK_STATUS) & PCIE_PORT_LINKUP); -} - static void mtk_pcie_subsys_powerdown(struct mtk_pcie *pcie) { struct device *dev = pcie->dev; @@ -171,12 +167,30 @@ static struct pci_ops mtk_pcie_ops = { .write = pci_generic_config_write, }; -static void mtk_pcie_configure_rc(struct mtk_pcie_port *port) +static int mtk_pcie_startup_port(struct mtk_pcie_port *port) { struct mtk_pcie *pcie = port->pcie; u32 func = PCI_FUNC(port->index << 3); u32 slot = PCI_SLOT(port->index << 3); u32 val; + int err; + + /* assert port PERST_N */ + val = readl(pcie->base + PCIE_SYS_CFG); + val |= PCIE_PORT_PERST(port->index); + writel(val, pcie->base + PCIE_SYS_CFG); + + /* de-assert port PERST_N */ + val = readl(pcie->base + PCIE_SYS_CFG); + val &= ~PCIE_PORT_PERST(port->index); + writel(val, pcie->base + PCIE_SYS_CFG); + + /* 100ms timeout value should be enough for Gen1/2 training */ + err = readl_poll_timeout(port->base + PCIE_LINK_STATUS, val, + !!(val & PCIE_PORT_LINKUP), 20, + 100 * USEC_PER_MSEC); + if (err) + return -ETIMEDOUT; /* enable interrupt */ val = readl(pcie->base + PCIE_INT_ENABLE); @@ -209,25 +223,8 @@ static void mtk_pcie_configure_rc(struct mtk_pcie_port *port) writel(PCIE_CONF_ADDR(PCIE_FTS_NUM, func, slot, 0), pcie->base + PCIE_CFG_ADDR); writel(val, pcie->base + PCIE_CFG_DATA); -} -static void mtk_pcie_assert_ports(struct mtk_pcie_port *port) -{ - struct mtk_pcie *pcie = port->pcie; - u32 val; - - /* assert port PERST_N */ - val = readl(pcie->base + PCIE_SYS_CFG); - val |= PCIE_PORT_PERST(port->index); - writel(val, pcie->base + PCIE_SYS_CFG); - - /* de-assert port PERST_N */ - val = readl(pcie->base + PCIE_SYS_CFG); - val &= ~PCIE_PORT_PERST(port->index); - writel(val, pcie->base + PCIE_SYS_CFG); - - /* PCIe v2.0 need at least 100ms delay to train from Gen1 to Gen2 */ - msleep(100); + return 0; } static void mtk_pcie_enable_ports(struct mtk_pcie_port *port) @@ -250,13 +247,8 @@ static void mtk_pcie_enable_ports(struct mtk_pcie_port *port) goto err_phy_on; } - mtk_pcie_assert_ports(port); - - /* if link up, then setup root port configuration space */ - if (mtk_pcie_link_up(port)) { - mtk_pcie_configure_rc(port); + if (!mtk_pcie_startup_port(port)) return; - } dev_info(dev, "Port%d link down\n", port->index);