On 2021/04/01 15:02, Greentime Hu wrote: > From: Paul Walmsley <paul.walmsley@xxxxxxxxxx> > > Add driver for the SiFive FU740 PCIe host controller. > This controller is based on the DesignWare PCIe core. > > Signed-off-by: Paul Walmsley <paul.walmsley@xxxxxxxxxx> > Co-developed-by: Henry Styles <hes@xxxxxxxxxx> > Signed-off-by: Henry Styles <hes@xxxxxxxxxx> > Co-developed-by: Erik Danie <erik.danie@xxxxxxxxxx> > Signed-off-by: Erik Danie <erik.danie@xxxxxxxxxx> > Co-developed-by: Greentime Hu <greentime.hu@xxxxxxxxxx> > Signed-off-by: Greentime Hu <greentime.hu@xxxxxxxxxx> > --- > drivers/pci/controller/dwc/Kconfig | 9 + > drivers/pci/controller/dwc/Makefile | 1 + > drivers/pci/controller/dwc/pcie-fu740.c | 324 ++++++++++++++++++++++++ > 3 files changed, 334 insertions(+) > create mode 100644 drivers/pci/controller/dwc/pcie-fu740.c > > diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig > index 22c5529e9a65..0a37d21ed64e 100644 > --- a/drivers/pci/controller/dwc/Kconfig > +++ b/drivers/pci/controller/dwc/Kconfig > @@ -318,4 +318,13 @@ config PCIE_AL > required only for DT-based platforms. ACPI platforms with the > Annapurna Labs PCIe controller don't need to enable this. > > +config PCIE_FU740 > + bool "SiFive FU740 PCIe host controller" > + depends on PCI_MSI_IRQ_DOMAIN > + depends on SOC_SIFIVE || COMPILE_TEST > + select PCIE_DW_HOST > + help > + Say Y here if you want PCIe controller support for the SiFive > + FU740. > + > endmenu > diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile > index a751553fa0db..625f6aaeb5b8 100644 > --- a/drivers/pci/controller/dwc/Makefile > +++ b/drivers/pci/controller/dwc/Makefile > @@ -5,6 +5,7 @@ obj-$(CONFIG_PCIE_DW_EP) += pcie-designware-ep.o > obj-$(CONFIG_PCIE_DW_PLAT) += pcie-designware-plat.o > obj-$(CONFIG_PCI_DRA7XX) += pci-dra7xx.o > obj-$(CONFIG_PCI_EXYNOS) += pci-exynos.o > +obj-$(CONFIG_PCIE_FU740) += pcie-fu740.o > obj-$(CONFIG_PCI_IMX6) += pci-imx6.o > obj-$(CONFIG_PCIE_SPEAR13XX) += pcie-spear13xx.o > obj-$(CONFIG_PCI_KEYSTONE) += pci-keystone.o > diff --git a/drivers/pci/controller/dwc/pcie-fu740.c b/drivers/pci/controller/dwc/pcie-fu740.c > new file mode 100644 > index 000000000000..ebbcbda97490 > --- /dev/null > +++ b/drivers/pci/controller/dwc/pcie-fu740.c > @@ -0,0 +1,324 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * FU740 DesignWare PCIe Controller integration > + * Copyright (C) 2019-2021 SiFive, Inc. > + * Paul Walmsley > + * Greentime Hu > + * > + * Based in part on the i.MX6 PCIe host controller shim which is: > + * > + * Copyright (C) 2013 Kosagi > + * https://www.kosagi.com > + */ > + > +#include <linux/clk.h> > +#include <linux/delay.h> > +#include <linux/gpio.h> > +#include <linux/kernel.h> > +#include <linux/mfd/syscon.h> > +#include <linux/module.h> > +#include <linux/of_gpio.h> > +#include <linux/of_device.h> > +#include <linux/pci.h> > +#include <linux/platform_device.h> > +#include <linux/regulator/consumer.h> > +#include <linux/resource.h> > +#include <linux/signal.h> > +#include <linux/types.h> > +#include <linux/interrupt.h> > +#include <linux/iopoll.h> > +#include <linux/reset.h> > +#include <linux/pm_domain.h> > +#include <linux/pm_runtime.h> > + > +#include "pcie-designware.h" > + > +#define to_fu740_pcie(x) dev_get_drvdata((x)->dev) > + > +struct fu740_pcie { > + struct dw_pcie pci; > + void __iomem *mgmt_base; > + struct gpio_desc *reset; > + struct gpio_desc *pwren; > + struct clk *pcie_aux; > + struct reset_control *rst; > +}; > + > +#define SIFIVE_DEVICESRESETREG 0x28 > + > +#define PCIEX8MGMT_PERST_N 0x0 > +#define PCIEX8MGMT_APP_LTSSM_ENABLE 0x10 > +#define PCIEX8MGMT_APP_HOLD_PHY_RST 0x18 > +#define PCIEX8MGMT_DEVICE_TYPE 0x708 > +#define PCIEX8MGMT_PHY0_CR_PARA_ADDR 0x860 > +#define PCIEX8MGMT_PHY0_CR_PARA_RD_EN 0x870 > +#define PCIEX8MGMT_PHY0_CR_PARA_RD_DATA 0x878 > +#define PCIEX8MGMT_PHY0_CR_PARA_SEL 0x880 > +#define PCIEX8MGMT_PHY0_CR_PARA_WR_DATA 0x888 > +#define PCIEX8MGMT_PHY0_CR_PARA_WR_EN 0x890 > +#define PCIEX8MGMT_PHY0_CR_PARA_ACK 0x898 > +#define PCIEX8MGMT_PHY1_CR_PARA_ADDR 0x8a0 > +#define PCIEX8MGMT_PHY1_CR_PARA_RD_EN 0x8b0 > +#define PCIEX8MGMT_PHY1_CR_PARA_RD_DATA 0x8b8 > +#define PCIEX8MGMT_PHY1_CR_PARA_SEL 0x8c0 > +#define PCIEX8MGMT_PHY1_CR_PARA_WR_DATA 0x8c8 > +#define PCIEX8MGMT_PHY1_CR_PARA_WR_EN 0x8d0 > +#define PCIEX8MGMT_PHY1_CR_PARA_ACK 0x8d8 > + > +#define PCIEX8MGMT_PHY_CDR_TRACK_EN BIT(0) > +#define PCIEX8MGMT_PHY_LOS_THRSHLD BIT(5) > +#define PCIEX8MGMT_PHY_TERM_EN BIT(9) > +#define PCIEX8MGMT_PHY_TERM_ACDC BIT(10) > +#define PCIEX8MGMT_PHY_EN BIT(11) > +#define PCIEX8MGMT_PHY_INIT_VAL (PCIEX8MGMT_PHY_CDR_TRACK_EN|\ > + PCIEX8MGMT_PHY_LOS_THRSHLD|\ > + PCIEX8MGMT_PHY_TERM_EN|\ > + PCIEX8MGMT_PHY_TERM_ACDC|\ > + PCIEX8MGMT_PHY_EN) > + > +#define PCIEX8MGMT_PHY_LANEN_DIG_ASIC_RX_OVRD_IN_3 0x1008 > +#define PCIEX8MGMT_PHY_LANE_OFF 0x100 > +#define PCIEX8MGMT_PHY_LANE0_BASE (PCIEX8MGMT_PHY_LANEN_DIG_ASIC_RX_OVRD_IN_3 + 0x100 * 0) > +#define PCIEX8MGMT_PHY_LANE1_BASE (PCIEX8MGMT_PHY_LANEN_DIG_ASIC_RX_OVRD_IN_3 + 0x100 * 1) > +#define PCIEX8MGMT_PHY_LANE2_BASE (PCIEX8MGMT_PHY_LANEN_DIG_ASIC_RX_OVRD_IN_3 + 0x100 * 2) > +#define PCIEX8MGMT_PHY_LANE3_BASE (PCIEX8MGMT_PHY_LANEN_DIG_ASIC_RX_OVRD_IN_3 + 0x100 * 3) > + > +static void fu740_pcie_assert_reset(struct fu740_pcie *afp) > +{ > + /* Assert PERST_N GPIO */ > + gpiod_set_value_cansleep(afp->reset, 0); > + /* Assert controller PERST_N */ > + writel_relaxed(0x0, afp->mgmt_base + PCIEX8MGMT_PERST_N); > +} > + > +static void fu740_pcie_deassert_reset(struct fu740_pcie *afp) > +{ > + /* Deassert controller PERST_N */ > + writel_relaxed(0x1, afp->mgmt_base + PCIEX8MGMT_PERST_N); > + /* Deassert PERST_N GPIO */ > + gpiod_set_value_cansleep(afp->reset, 1); > +} > + > +static void fu740_pcie_power_on(struct fu740_pcie *afp) > +{ > + gpiod_set_value_cansleep(afp->pwren, 1); > + /* > + * Ensure that PERST has been asserted for at least 100 ms. > + * Section 2.2 of PCI Express Card Electromechanical Specification > + * Revision 3.0 > + */ > + msleep(100); > +} > + > +static void fu740_pcie_drive_reset(struct fu740_pcie *afp) > +{ > + fu740_pcie_assert_reset(afp); > + fu740_pcie_power_on(afp); > + fu740_pcie_deassert_reset(afp); > +} > + > +static void fu740_phyregwrite(const uint8_t phy, const uint16_t addr, > + const uint16_t wrdata, struct fu740_pcie *afp) > +{ > + struct device *dev = afp->pci.dev; > + void __iomem *phy_cr_para_addr; > + void __iomem *phy_cr_para_wr_data; > + void __iomem *phy_cr_para_wr_en; > + void __iomem *phy_cr_para_ack; > + int ret, val; > + > + /* Setup */ > + if (phy) { > + phy_cr_para_addr = afp->mgmt_base + PCIEX8MGMT_PHY1_CR_PARA_ADDR; > + phy_cr_para_wr_data = afp->mgmt_base + PCIEX8MGMT_PHY1_CR_PARA_WR_DATA; > + phy_cr_para_wr_en = afp->mgmt_base + PCIEX8MGMT_PHY1_CR_PARA_WR_EN; > + phy_cr_para_ack = afp->mgmt_base + PCIEX8MGMT_PHY1_CR_PARA_ACK; > + } else { > + phy_cr_para_addr = afp->mgmt_base + PCIEX8MGMT_PHY0_CR_PARA_ADDR; > + phy_cr_para_wr_data = afp->mgmt_base + PCIEX8MGMT_PHY0_CR_PARA_WR_DATA; > + phy_cr_para_wr_en = afp->mgmt_base + PCIEX8MGMT_PHY0_CR_PARA_WR_EN; > + phy_cr_para_ack = afp->mgmt_base + PCIEX8MGMT_PHY0_CR_PARA_ACK; > + } > + > + writel_relaxed(addr, phy_cr_para_addr); > + writel_relaxed(wrdata, phy_cr_para_wr_data); > + writel_relaxed(1, phy_cr_para_wr_en); > + > + /* Wait for wait_idle */ > + ret = readl_poll_timeout(phy_cr_para_ack, val, val, 10, 5000); > + if (ret) > + dev_err(dev, "Wait for wait_ilde state failed!\n"); This is a void function. What is the point of these dev_err() if you do not return an error or process the failure in any way ? Change this to dev_warn() may be ? > + > + /* Clear */ > + writel_relaxed(0, phy_cr_para_wr_en); > + > + /* Wait for ~wait_idle */ > + ret = readl_poll_timeout(phy_cr_para_ack, val, !val, 10, 5000); > + if (ret) > + dev_err(dev, "Wait for !wait_ilde state failed!\n"); Same as above. > +} > + > +static void fu740_pcie_init_phy(struct fu740_pcie *afp) > +{ > + /* Enable phy cr_para_sel interfaces */ > + writel_relaxed(0x1, afp->mgmt_base + PCIEX8MGMT_PHY0_CR_PARA_SEL); > + writel_relaxed(0x1, afp->mgmt_base + PCIEX8MGMT_PHY1_CR_PARA_SEL); > + > + /* > + * Wait 10 cr_para cycles to guarantee that the registers are ready > + * to be edited. > + */ > + ndelay(10); > + > + /* Set PHY AC termination mode */ > + fu740_phyregwrite(0, PCIEX8MGMT_PHY_LANE0_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp); > + fu740_phyregwrite(0, PCIEX8MGMT_PHY_LANE1_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp); > + fu740_phyregwrite(0, PCIEX8MGMT_PHY_LANE2_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp); > + fu740_phyregwrite(0, PCIEX8MGMT_PHY_LANE3_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp); > + fu740_phyregwrite(1, PCIEX8MGMT_PHY_LANE0_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp); > + fu740_phyregwrite(1, PCIEX8MGMT_PHY_LANE1_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp); > + fu740_phyregwrite(1, PCIEX8MGMT_PHY_LANE2_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp); > + fu740_phyregwrite(1, PCIEX8MGMT_PHY_LANE3_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp); > +} > + > +static void fu740_pcie_ltssm_enable(struct device *dev) > +{ > + struct fu740_pcie *afp = dev_get_drvdata(dev); > + > + /* Enable LTSSM */ > + writel_relaxed(0x1, afp->mgmt_base + PCIEX8MGMT_APP_LTSSM_ENABLE); > +} > + > +static int fu740_pcie_start_link(struct dw_pcie *pci) > +{ > + struct device *dev = pci->dev; No need for this variable. > + > + /* Start LTSSM. */ > + fu740_pcie_ltssm_enable(dev); > + return 0; > +} > + > +static int fu740_pcie_host_init(struct pcie_port *pp) > +{ > + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); > + struct fu740_pcie *afp = to_fu740_pcie(pci); > + struct device *dev = pci->dev; > + int ret; > + > + /* Power on reset */ > + fu740_pcie_drive_reset(afp); > + > + /* Enable pcieauxclk */ > + ret = clk_prepare_enable(afp->pcie_aux); > + if (ret) > + dev_err(dev, "unable to enable pcie_aux clock\n"); No bailing out ? Without a clock, is this going to work ? If that is not a problem, then I would suggest a dev_warn() here. > + > + /* > + * Assert hold_phy_rst (hold the controller LTSSM in reset after > + * power_up_rst_n for register programming with cr_para) > + */ > + writel_relaxed(0x1, afp->mgmt_base + PCIEX8MGMT_APP_HOLD_PHY_RST); > + > + /* Deassert power_up_rst_n */ > + ret = reset_control_deassert(afp->rst); > + if (ret) > + dev_err(dev, "unable to deassert pcie_power_up_rst_n\n"); Same as above. > + > + fu740_pcie_init_phy(afp); > + > + /* Disable pcieauxclk */ > + clk_disable_unprepare(afp->pcie_aux); > + /* Clear hold_phy_rst */ > + writel_relaxed(0x0, afp->mgmt_base + PCIEX8MGMT_APP_HOLD_PHY_RST); > + /* Enable pcieauxclk */ > + ret = clk_prepare_enable(afp->pcie_aux); > + /* Set RC mode */ > + writel_relaxed(0x4, afp->mgmt_base + PCIEX8MGMT_DEVICE_TYPE); > + > + return 0; > +} > + > +static const struct dw_pcie_host_ops fu740_pcie_host_ops = { > + .host_init = fu740_pcie_host_init, > +}; > + > +static const struct dw_pcie_ops dw_pcie_ops = { > + .start_link = fu740_pcie_start_link, > +}; > + > +static int fu740_pcie_probe(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct dw_pcie *pci; > + struct fu740_pcie *afp; > + int ret; > + > + afp = devm_kzalloc(dev, sizeof(*afp), GFP_KERNEL); > + if (!afp) > + return -ENOMEM; > + pci = &afp->pci; > + pci->dev = dev; > + pci->ops = &dw_pcie_ops; > + pci->pp.ops = &fu740_pcie_host_ops; > + > + /* SiFive specific region: mgmt */ > + afp->mgmt_base = devm_platform_ioremap_resource_byname(pdev, "mgmt"); > + if (IS_ERR(afp->mgmt_base)) > + return PTR_ERR(afp->mgmt_base); > + > + /* Fetch GPIOs */ > + afp->reset = devm_gpiod_get_optional(dev, "reset-gpios", GPIOD_OUT_LOW); > + if (IS_ERR(afp->reset)) { > + dev_err(dev, "unable to get reset-gpios\n"); > + return ret; > + } > + afp->pwren = devm_gpiod_get_optional(dev, "pwren-gpios", GPIOD_OUT_LOW); > + if (IS_ERR(afp->pwren)) { > + dev_err(dev, "unable to get pwren-gpios\n"); > + return ret; Why not return dev_err_probe(...); ? Same for the returns above. > + } > + > + /* Fetch clocks */ > + afp->pcie_aux = devm_clk_get(dev, "pcie_aux"); > + if (IS_ERR(afp->pcie_aux)) > + return dev_err_probe(dev, PTR_ERR(afp->pcie_aux), > + "pcie_aux clock source missing or invalid\n"); > + > + /* Fetch reset */ > + afp->rst = devm_reset_control_get_exclusive(dev, NULL); > + if (IS_ERR(afp->rst)) > + return dev_err_probe(dev, PTR_ERR(afp->rst), "unable to get reset\n"); > + > + platform_set_drvdata(pdev, afp); > + > + ret = dw_pcie_host_init(&pci->pp); > + if (ret < 0) > + return ret; You can simplify this with a simple: return dw_pcie_host_init(&pci->pp); > + > + return 0; > +} > + > +static void fu740_pcie_shutdown(struct platform_device *pdev) > +{ > + struct fu740_pcie *afp = platform_get_drvdata(pdev); > + > + /* Bring down link, so bootloader gets clean state in case of reboot */ > + fu740_pcie_assert_reset(afp); > +} > + > +static const struct of_device_id fu740_pcie_of_match[] = { > + { .compatible = "sifive,fu740-pcie", }, > + {}, > +}; > + > +static struct platform_driver fu740_pcie_driver = { > + .driver = { > + .name = "fu740-pcie", > + .of_match_table = fu740_pcie_of_match, > + .suppress_bind_attrs = true, > + }, > + .probe = fu740_pcie_probe, > + .shutdown = fu740_pcie_shutdown, > +}; > + > +builtin_platform_driver(fu740_pcie_driver); > -- Damien Le Moal Western Digital Research
