diff --git a/arch/mips/pci/pci-ar724x.c b/arch/mips/pci/pci-ar724x.c index 1e23c8d587bd..64b58cc48a91 100644 --- a/arch/mips/pci/pci-ar724x.c +++ b/arch/mips/pci/pci-ar724x.c @@ -12,14 +12,18 @@ #include #include #include +#include #include #include #include +#define AR724X_PCI_REG_APP 0x00 #define AR724X_PCI_REG_RESET 0x18 #define AR724X_PCI_REG_INT_STATUS 0x4c #define AR724X_PCI_REG_INT_MASK 0x50 +#define AR724X_PCI_APP_LTSSM_ENABLE BIT(0) + #define AR724X_PCI_RESET_LINK_UP BIT(0) #define AR724X_PCI_INT_DEV0 BIT(14) @@ -325,6 +329,37 @@ static void ar724x_pci_irq_init(struct ar724x_pci_controller *apc, apc); } +static void ar724x_pci_hw_init(struct ar724x_pci_controller *apc) +{ + u32 ppl, app; + int wait = 0; + + /* deassert PCIe host controller and PCIe PHY reset */ + ath79_device_reset_clear(AR724X_RESET_PCIE); + ath79_device_reset_clear(AR724X_RESET_PCIE_PHY); + + /* remove the reset of the PCIE PLL */ + ppl = ath79_pll_rr(AR724X_PLL_REG_PCIE_CONFIG); + ppl &= ~AR724X_PLL_REG_PCIE_CONFIG_PPL_RESET; + ath79_pll_wr(AR724X_PLL_REG_PCIE_CONFIG, ppl); + + /* deassert bypass for the PCIE PLL */ + ppl = ath79_pll_rr(AR724X_PLL_REG_PCIE_CONFIG); + ppl &= ~AR724X_PLL_REG_PCIE_CONFIG_PPL_BYPASS; + ath79_pll_wr(AR724X_PLL_REG_PCIE_CONFIG, ppl); + + /* set PCIE Application Control to ready */ + app = __raw_readl(apc->ctrl_base + AR724X_PCI_REG_APP); + app |= AR724X_PCI_APP_LTSSM_ENABLE; + __raw_writel(app, apc->ctrl_base + AR724X_PCI_REG_APP); + + /* wait up to 100ms for PHY link up */ + do { + mdelay(10); + wait++; + } while (wait < 10 && !ar724x_pci_check_link(apc)); +} + static int ar724x_pci_probe(struct platform_device *pdev) { struct ar724x_pci_controller *apc; @@ -383,6 +418,13 @@ static int ar724x_pci_probe(struct platform_device *pdev) apc->pci_controller.io_resource = &apc->io_res; apc->pci_controller.mem_resource = &apc->mem_res; + /* + * Do the full PCIE Root Complex Initialization Sequence if the PCIe + * host controller is in reset. + */ + if (ath79_reset_rr(AR724X_RESET_REG_RESET_MODULE) & AR724X_RESET_PCIE) + ar724x_pci_hw_init(apc); + apc->link_up = ar724x_pci_check_link(apc); if (!apc->link_up) dev_warn(&pdev->dev, "PCIe link is down\n");