From 366697018c9a2aa67d457bfdc495115cface6ae8 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Marek=20Beh=C3=BAn?= Date: Thu, 30 Apr 2020 10:06:20 +0200 Subject: [PATCH] PCI: aardvark: Add PHY support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit With recent proposed changes for U-Boot it is possible that bootloader won't initialize the PHY for this controller (currently the PHY is initialized regardless whether PCI is used in U-Boot, but with these proposed changes the PHY is initialized only on request). Since the mvebu-a3700-comphy driver by Miquèl Raynal supports enabling PCIe PHY, and since Linux' functionality should be independent on what bootloader did, add code for enabling generic PHY if found in device OF node. The mvebu-a3700-comphy driver does PHY powering via SMC calls to ARM Trusted Firmware. The corresponding code in ARM Trusted Firmware skips one register write which U-Boot does not: step 7 ("Enable TX"), see [1]. Instead ARM Trusted Firmware expects PCIe driver to do this step, probably because the register is in PCIe controller address space, instead of PHY address space. We therefore add this step into the advk_pcie_setup_hw function. [1] https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/tree/drivers/marvell/comphy/phy-comphy-3700.c?h=v2.3-rc2#n836 Link: https://lore.kernel.org/r/20200430080625.26070-8-pali@kernel.org Tested-by: Tomasz Maciej Nowak Signed-off-by: Marek Behún Signed-off-by: Lorenzo Pieralisi Reviewed-by: Rob Herring Acked-by: Thomas Petazzoni Cc: Miquèl Raynal --- drivers/pci/controller/pci-aardvark.c | 69 +++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) --- a/drivers/pci/controller/pci-aardvark.c +++ b/drivers/pci/controller/pci-aardvark.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include #include @@ -90,6 +91,8 @@ #define PCIE_CORE_CTRL2_STRICT_ORDER_ENABLE BIT(5) #define PCIE_CORE_CTRL2_OB_WIN_ENABLE BIT(6) #define PCIE_CORE_CTRL2_MSI_ENABLE BIT(10) +#define PCIE_CORE_REF_CLK_REG (CONTROL_BASE_ADDR + 0x14) +#define PCIE_CORE_REF_CLK_TX_ENABLE BIT(1) #define PCIE_MSG_LOG_REG (CONTROL_BASE_ADDR + 0x30) #define PCIE_ISR0_REG (CONTROL_BASE_ADDR + 0x40) #define PCIE_MSG_PM_PME_MASK BIT(7) @@ -289,6 +292,7 @@ struct advk_pcie { int link_gen; struct pci_bridge_emul bridge; struct gpio_desc *reset_gpio; + struct phy *phy; }; static inline void advk_writel(struct advk_pcie *pcie, u32 val, u64 reg) @@ -482,6 +486,11 @@ static void advk_pcie_setup_hw(struct ad u32 reg; int i; + /* Enable TX */ + reg = advk_readl(pcie, PCIE_CORE_REF_CLK_REG); + reg |= PCIE_CORE_REF_CLK_TX_ENABLE; + advk_writel(pcie, reg, PCIE_CORE_REF_CLK_REG); + /* Set to Direct mode */ reg = advk_readl(pcie, CTRL_CONFIG_REG); reg &= ~(CTRL_MODE_MASK << CTRL_MODE_SHIFT); @@ -1491,6 +1500,62 @@ out_release_res: return err; } +static void __maybe_unused advk_pcie_disable_phy(struct advk_pcie *pcie) +{ + phy_power_off(pcie->phy); + phy_exit(pcie->phy); +} + +static int advk_pcie_enable_phy(struct advk_pcie *pcie) +{ + int ret; + + if (!pcie->phy) + return 0; + + ret = phy_init(pcie->phy); + if (ret) + return ret; + + ret = phy_set_mode(pcie->phy, PHY_MODE_PCIE); + if (ret) { + phy_exit(pcie->phy); + return ret; + } + + ret = phy_power_on(pcie->phy); + if (ret) { + phy_exit(pcie->phy); + return ret; + } + + return 0; +} + +static int advk_pcie_setup_phy(struct advk_pcie *pcie) +{ + struct device *dev = &pcie->pdev->dev; + struct device_node *node = dev->of_node; + int ret = 0; + + pcie->phy = devm_of_phy_get(dev, node, NULL); + if (IS_ERR(pcie->phy) && (PTR_ERR(pcie->phy) == -EPROBE_DEFER)) + return PTR_ERR(pcie->phy); + + /* Old bindings miss the PHY handle */ + if (IS_ERR(pcie->phy)) { + dev_warn(dev, "PHY unavailable (%ld)\n", PTR_ERR(pcie->phy)); + pcie->phy = NULL; + return 0; + } + + ret = advk_pcie_enable_phy(pcie); + if (ret) + dev_err(dev, "Failed to initialize PHY (%d)\n", ret); + + return ret; +} + static int advk_pcie_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -1623,6 +1688,10 @@ static int advk_pcie_probe(struct platfo else pcie->link_gen = ret; + ret = advk_pcie_setup_phy(pcie); + if (ret) + return ret; + advk_pcie_setup_hw(pcie); ret = advk_sw_pci_bridge_init(pcie);