== On Wed, May 5, 2021 at 8:35 PM Simon Xue <xxm@xxxxxxxxxxxxxx> wrote: > > Add a driver for the DesignWare-based PCIe controller found on > RK356X. The existing pcie-rockchip-host driver is only used for > the Rockchip-designed IP found on RK3399. > > Tested-by: Peter Geis <pgwipeout@xxxxxxxxx> > Reviewed-by: Kever Yang <kever.yang@xxxxxxxxxxxxxx> > Reported-by: kernel test robot <lkp@xxxxxxxxx> > Signed-off-by: Simon Xue <xxm@xxxxxxxxxxxxxx> > Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx> > --- > drivers/pci/controller/dwc/Kconfig | 11 + > drivers/pci/controller/dwc/Makefile | 1 + > drivers/pci/controller/dwc/pcie-dw-rockchip.c | 277 ++++++++++++++++++ > 3 files changed, 289 insertions(+) > create mode 100644 drivers/pci/controller/dwc/pcie-dw-rockchip.c > > diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig > index 423d35872ce4..60d3dde9ca39 100644 > --- a/drivers/pci/controller/dwc/Kconfig > +++ b/drivers/pci/controller/dwc/Kconfig > @@ -214,6 +214,17 @@ config PCIE_ARTPEC6_EP > Enables support for the PCIe controller in the ARTPEC-6 SoC to work in > endpoint mode. This uses the DesignWare core. > > +config PCIE_ROCKCHIP_DW_HOST > + bool "Rockchip DesignWare PCIe controller" > + select PCIE_DW > + select PCIE_DW_HOST > + depends on PCI_MSI_IRQ_DOMAIN > + depends on ARCH_ROCKCHIP || COMPILE_TEST > + depends on OF > + help > + Enables support for the DesignWare PCIe controller in the > + Rockchip SoC except RK3399. > + > config PCIE_INTEL_GW > bool "Intel Gateway PCIe host controller support" > depends on OF && (X86 || COMPILE_TEST) > diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile > index eca805c1a023..689b06a7d334 100644 > --- a/drivers/pci/controller/dwc/Makefile > +++ b/drivers/pci/controller/dwc/Makefile > @@ -14,6 +14,7 @@ obj-$(CONFIG_PCI_LAYERSCAPE_EP) += pci-layerscape-ep.o > obj-$(CONFIG_PCIE_QCOM) += pcie-qcom.o > obj-$(CONFIG_PCIE_ARMADA_8K) += pcie-armada8k.o > obj-$(CONFIG_PCIE_ARTPEC6) += pcie-artpec6.o > +obj-$(CONFIG_PCIE_ROCKCHIP_DW_HOST) += pcie-dw-rockchip.o > obj-$(CONFIG_PCIE_INTEL_GW) += pcie-intel-gw.o > obj-$(CONFIG_PCIE_KIRIN) += pcie-kirin.o > obj-$(CONFIG_PCIE_HISI_STB) += pcie-histb.o > diff --git a/drivers/pci/controller/dwc/pcie-dw-rockchip.c b/drivers/pci/controller/dwc/pcie-dw-rockchip.c > new file mode 100644 > index 000000000000..3f060144eeab > --- /dev/null > +++ b/drivers/pci/controller/dwc/pcie-dw-rockchip.c > @@ -0,0 +1,277 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * PCIe host controller driver for Rockchip SoCs. > + * > + * Copyright (C) 2021 Rockchip Electronics Co., Ltd. > + * http://www.rock-chips.com > + * > + * Author: Simon Xue <xxm@xxxxxxxxxxxxxx> > + */ > + > +#include <linux/clk.h> > +#include <linux/gpio/consumer.h> > +#include <linux/mfd/syscon.h> > +#include <linux/module.h> > +#include <linux/of_device.h> > +#include <linux/phy/phy.h> > +#include <linux/platform_device.h> > +#include <linux/regmap.h> > +#include <linux/reset.h> > + > +#include "pcie-designware.h" > + > +/* > + * The upper 16 bits of PCIE_CLIENT_CONFIG are a write > + * mask for the lower 16 bits. > + */ > +#define HIWORD_UPDATE(mask, val) (((mask) << 16) | (val)) > +#define HIWORD_UPDATE_BIT(val) HIWORD_UPDATE(val, val) > + > +#define to_rockchip_pcie(x) dev_get_drvdata((x)->dev) > + > +#define PCIE_CLIENT_RC_MODE HIWORD_UPDATE_BIT(0x40) > +#define PCIE_CLIENT_ENABLE_LTSSM HIWORD_UPDATE_BIT(0xc) > +#define PCIE_SMLH_LINKUP BIT(16) > +#define PCIE_RDLH_LINKUP BIT(17) > +#define PCIE_LINKUP (PCIE_SMLH_LINKUP | PCIE_RDLH_LINKUP) > +#define PCIE_L0S_ENTRY 0x11 > +#define PCIE_CLIENT_GENERAL_CONTROL 0x0 > +#define PCIE_CLIENT_GENERAL_DEBUG 0x104 > +#define PCIE_CLIENT_HOT_RESET_CTRL 0x180 > +#define PCIE_CLIENT_LTSSM_STATUS 0x300 > +#define PCIE_LTSSM_ENABLE_ENHANCE BIT(4) > + > +struct rockchip_pcie { > + struct dw_pcie pci; > + void __iomem *apb_base; > + struct phy *phy; > + struct clk_bulk_data *clks; > + unsigned int clk_cnt; > + struct reset_control *rst; > + struct gpio_desc *rst_gpio; > + struct regulator *vpcie3v3; > +}; > + > +static int rockchip_pcie_readl_apb(struct rockchip_pcie *rockchip, > + u32 reg) > +{ > + return readl(rockchip->apb_base + reg); Use _relaxed variant. > +} > + > +static void rockchip_pcie_writel_apb(struct rockchip_pcie *rockchip, > + u32 val, u32 reg) > +{ > + writel(val, rockchip->apb_base + reg); Use _relaxed variant. > +} > + > +static void rockchip_pcie_enable_ltssm(struct rockchip_pcie *rockchip) > +{ > + rockchip_pcie_writel_apb(rockchip, PCIE_CLIENT_ENABLE_LTSSM, > + PCIE_CLIENT_GENERAL_CONTROL); > +} > + > +static int rockchip_pcie_link_up(struct dw_pcie *pci) > +{ > + struct rockchip_pcie *rockchip = to_rockchip_pcie(pci); > + u32 val = rockchip_pcie_readl_apb(rockchip, PCIE_CLIENT_LTSSM_STATUS); > + > + if ((val & (PCIE_RDLH_LINKUP | PCIE_SMLH_LINKUP)) == PCIE_LINKUP && ((val & PCIE_LINKUP) == PCIE_LINKUP) > + (val & GENMASK(5, 0)) == PCIE_L0S_ENTRY) Perhaps a define for GENMASK(5, 0) > + return 1; > + > + return 0; > +} > + > +static int rockchip_pcie_start_link(struct dw_pcie *pci) > +{ > + struct rockchip_pcie *rockchip = to_rockchip_pcie(pci); > + > + /* Reset device */ > + gpiod_set_value_cansleep(rockchip->rst_gpio, 0); With gpiod, 0 means inactive which is reset deasserted. Your DT should have an ACTIVE_LOW flag. > + > + rockchip_pcie_enable_ltssm(rockchip); > + > + /* > + * PCIe requires the refclk to be stable for 100µs prior to releasing > + * PERST. See table 2-4 in section 2.6.2 AC Specifications of the PCI > + * Express Card Electromechanical Specification, 1.1. However, we don't > + * know if the refclk is coming from RC's PHY or external OSC. If it's > + * from RC, so enabling LTSSM is the just right place to release #PERST. > + * We need more extra time as before, rather than setting just > + * 100us as we don't know how long should the device need to reset. > + */ > + msleep(100); > + gpiod_set_value_cansleep(rockchip->rst_gpio, 1); > + > + return 0; > +} > + > +static int rockchip_pcie_host_init(struct pcie_port *pp) > +{ > + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); > + struct rockchip_pcie *rockchip = to_rockchip_pcie(pci); > + u32 val; > + > + /* LTSSM enable control mode */ > + val = rockchip_pcie_readl_apb(rockchip, PCIE_CLIENT_HOT_RESET_CTRL); > + val |= PCIE_LTSSM_ENABLE_ENHANCE | (PCIE_LTSSM_ENABLE_ENHANCE << 16); Since you have a write mask, why do you need to do a read-mod-write? And why not use HIWORD_UPDATE_BIT? > + rockchip_pcie_writel_apb(rockchip, val, PCIE_CLIENT_HOT_RESET_CTRL); > + > + rockchip_pcie_writel_apb(rockchip, PCIE_CLIENT_RC_MODE, > + PCIE_CLIENT_GENERAL_CONTROL); > + > + return 0; > +}