| Message ID | 20230823091153.2578417-17-yoshihiro.shimoda.uh@renesas.com |
|---|---|
| State | New |
| Headers | show |
| Series | PCI: rcar-gen4: Add R-Car Gen4 PCIe support | expand |
On Wed, Aug 23, 2023 at 06:11:50PM +0900, Yoshihiro Shimoda wrote: > Add R-Car Gen4 PCIe Host support. This controller is based on > Synopsys DesignWare PCIe, but this controller has vendor-specific > registers so that requires initialization code like mode setting > and retraining and so on. > > To reduce code delta, adds some helper functions which are used by > both the host driver and the endpoint driver (which is added > immediately afterwards) into a separate file. > > Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> > --- > drivers/pci/controller/dwc/Kconfig | 10 + > drivers/pci/controller/dwc/Makefile | 2 + > .../controller/dwc/pcie-rcar-gen4-host-drv.c | 145 ++++++++++++ > drivers/pci/controller/dwc/pcie-rcar-gen4.c | 208 ++++++++++++++++++ > drivers/pci/controller/dwc/pcie-rcar-gen4.h | 44 ++++ > 5 files changed, 409 insertions(+) > create mode 100644 drivers/pci/controller/dwc/pcie-rcar-gen4-host-drv.c > create mode 100644 drivers/pci/controller/dwc/pcie-rcar-gen4.c > create mode 100644 drivers/pci/controller/dwc/pcie-rcar-gen4.h > > diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig > index ab96da43e0c2..3884a67e4d56 100644 > --- a/drivers/pci/controller/dwc/Kconfig > +++ b/drivers/pci/controller/dwc/Kconfig > @@ -415,4 +415,14 @@ config PCIE_VISCONTI_HOST > Say Y here if you want PCIe controller support on Toshiba Visconti SoC. > This driver supports TMPV7708 SoC. > > +config PCIE_RCAR_GEN4 > + tristate "Renesas R-Car Gen4 PCIe Host controller" > + depends on ARCH_RENESAS || COMPILE_TEST > + depends on PCI_MSI > + select PCIE_DW_HOST > + help > + Say Y here if you want PCIe host controller support on R-Car Gen4 SoCs. > + To compile this driver as a module, choose M here: the module will be > + called pcie-rcar-gen4-host.ko. This uses the DesignWare core. > + > endmenu > diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile > index bf5c311875a1..ab2c6bc16216 100644 > --- a/drivers/pci/controller/dwc/Makefile > +++ b/drivers/pci/controller/dwc/Makefile > @@ -26,6 +26,8 @@ obj-$(CONFIG_PCIE_TEGRA194) += pcie-tegra194.o > obj-$(CONFIG_PCIE_UNIPHIER) += pcie-uniphier.o > obj-$(CONFIG_PCIE_UNIPHIER_EP) += pcie-uniphier-ep.o > obj-$(CONFIG_PCIE_VISCONTI_HOST) += pcie-visconti.o > +pcie-rcar-gen4-host-objs := pcie-rcar-gen4.o pcie-rcar-gen4-host-drv.o > +obj-$(CONFIG_PCIE_RCAR_GEN4) += pcie-rcar-gen4-host.o > > # The following drivers are for devices that use the generic ACPI > # pci_root.c driver but don't support standard ECAM config access. > diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4-host-drv.c b/drivers/pci/controller/dwc/pcie-rcar-gen4-host-drv.c > new file mode 100644 > index 000000000000..8acce1ee5efc > --- /dev/null > +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4-host-drv.c > @@ -0,0 +1,145 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * PCIe host controller driver for Renesas R-Car Gen4 Series SoCs > + * Copyright (C) 2022-2023 Renesas Electronics Corporation > + */ > + > +#include <linux/delay.h> > +#include <linux/interrupt.h> > +#include <linux/module.h> > +#include <linux/of_device.h> > +#include <linux/pci.h> > +#include <linux/platform_device.h> > + > +#include "pcie-rcar-gen4.h" > +#include "pcie-designware.h" > + > +static int rcar_gen4_pcie_host_init(struct dw_pcie_rp *pp) > +{ > + struct dw_pcie *dw = to_dw_pcie_from_pp(pp); > + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); > + int ret; > + u32 val; > + > + gpiod_set_value_cansleep(dw->pe_rst, 1); > + > + ret = clk_bulk_prepare_enable(DW_PCIE_NUM_CORE_CLKS, dw->core_clks); > + if (ret) { > + dev_err(dw->dev, "Failed to enable ref clocks\n"); > + return ret; > + } This is called in both the Host and End-point init function right above the rcar_gen4_pcie_common_init() method invocation. It can be moved there then. > + > + ret = rcar_gen4_pcie_common_init(rcar); > + if (ret) { > + clk_bulk_disable_unprepare(DW_PCIE_NUM_CORE_CLKS, dw->core_clks); > + return ret; > + } > + > + /* > + * According to the section 3.5.7.2 "RC Mode" in DWC PCIe Dual Mode > + * Rev.5.20a, we should disable two BARs to avoid unnecessary memory > + * assignment during device enumeration. > + */ > + dw_pcie_writel_dbi2(dw, PCI_BASE_ADDRESS_0, 0x0); > + dw_pcie_writel_dbi2(dw, PCI_BASE_ADDRESS_1, 0x0); > + > + /* Enable MSI interrupt signal */ > + val = readl(rcar->base + PCIEINTSTS0EN); > + val |= MSI_CTRL_INT; > + writel(val, rcar->base + PCIEINTSTS0EN); > + > + msleep(100); /* pe_rst requires 100msec delay */ > + > + gpiod_set_value_cansleep(dw->pe_rst, 0); > + > + return 0; > +} > + > +static void rcar_gen4_pcie_host_deinit(struct dw_pcie_rp *pp) > +{ > + struct dw_pcie *dw = to_dw_pcie_from_pp(pp); > + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); > + > + gpiod_set_value_cansleep(dw->pe_rst, 1); > + rcar_gen4_pcie_common_deinit(rcar); > + clk_bulk_disable_unprepare(DW_PCIE_NUM_CORE_CLKS, dw->core_clks); and this can be moved to rcar_gen4_pcie_common_deinit() too for the same reason as denoted in the previous comment. > +} > + > +static const struct dw_pcie_host_ops rcar_gen4_pcie_host_ops = { > + .host_init = rcar_gen4_pcie_host_init, > + .host_deinit = rcar_gen4_pcie_host_deinit, > +}; > + > +static int rcar_gen4_add_dw_pcie_rp(struct rcar_gen4_pcie *rcar) > +{ > + struct dw_pcie_rp *pp = &rcar->dw.pp; > + > + pp->num_vectors = MAX_MSI_IRQS; > + pp->ops = &rcar_gen4_pcie_host_ops; > + rcar->mode = DW_PCIE_RC_TYPE; > + > + return dw_pcie_host_init(pp); > +} > + > +static void rcar_gen4_remove_dw_pcie_rp(struct rcar_gen4_pcie *rcar) > +{ > + dw_pcie_host_deinit(&rcar->dw.pp); > + gpiod_set_value_cansleep(rcar->dw.pe_rst, 1); gpiod_set_value_cansleep() seems redundant here because dw_pcie_host_deinit() calls host_deinit() which is rcar_gen4_pcie_host_deinit() and which already asserts the PE_RST GPIO. BTW even though after dropping the gpiod_set_value_cansleep() function call from rcar_gen4_remove_dw_pcie_rp(), the later will be left with only a single function invocation I would have left it defined anyway for the internal driver interface consistency and maintainability: you'll have a protagonist and respective antagonist defined in a way it's done for host_init()/host_deinit(), common_init()/common_deinit(), prepare()/unprepare(), etc. In addition such design would simplify possible updates should you need to extend rcar_gen4_add_dw_pcie_rp() functionality and add new cleanups afterwards. > +} > + > +static int rcar_gen4_pcie_probe(struct platform_device *pdev) > +{ > + struct rcar_gen4_pcie *rcar; > + int err; > + > + rcar = rcar_gen4_pcie_devm_alloc(pdev); > + if (IS_ERR(rcar)) > + return PTR_ERR(rcar); > + > + err = rcar_gen4_pcie_get_resources(rcar); > + if (err) > + return err; > + > + err = rcar_gen4_pcie_prepare(rcar); > + if (err) > + return err; > + > + err = rcar_gen4_add_dw_pcie_rp(rcar); > + if (err) > + goto err_unprepare; > + > + return 0; > + > +err_unprepare: > + rcar_gen4_pcie_unprepare(rcar); > + > + return err; > +} Look how neat and beautiful the probe() method is now. So is the rest of the driver.) So to speak with the previous notes fixed feel free to add: Reviewed-by: Serge Semin <fancer.lancer@gmail.com> -Serge(y) > + > +static void rcar_gen4_pcie_remove(struct platform_device *pdev) > +{ > + struct rcar_gen4_pcie *rcar = platform_get_drvdata(pdev); > + > + rcar_gen4_remove_dw_pcie_rp(rcar); > + rcar_gen4_pcie_unprepare(rcar); > +} > + > +static const struct of_device_id rcar_gen4_pcie_of_match[] = { > + { .compatible = "renesas,rcar-gen4-pcie", }, > + {}, > +}; > +MODULE_DEVICE_TABLE(of, rcar_gen4_pcie_of_match); > + > +static struct platform_driver rcar_gen4_pcie_driver = { > + .driver = { > + .name = "pcie-rcar-gen4", > + .of_match_table = rcar_gen4_pcie_of_match, > + .probe_type = PROBE_PREFER_ASYNCHRONOUS, > + }, > + .probe = rcar_gen4_pcie_probe, > + .remove_new = rcar_gen4_pcie_remove, > +}; > +module_platform_driver(rcar_gen4_pcie_driver); > + > +MODULE_DESCRIPTION("Renesas R-Car Gen4 PCIe host controller driver"); > +MODULE_LICENSE("GPL"); > diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c > new file mode 100644 > index 000000000000..2a8bbf928d5f > --- /dev/null > +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c > @@ -0,0 +1,208 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * PCIe host/endpoint controller driver for Renesas R-Car Gen4 Series SoCs > + * Copyright (C) 2022-2023 Renesas Electronics Corporation > + */ > + > +#include <linux/delay.h> > +#include <linux/io.h> > +#include <linux/of_device.h> > +#include <linux/pci.h> > +#include <linux/pm_runtime.h> > +#include <linux/reset.h> > + > +#include "pcie-rcar-gen4.h" > +#include "pcie-designware.h" > + > +/* Renesas-specific */ > +#define PCIERSTCTRL1 0x0014 > +#define APP_HOLD_PHY_RST BIT(16) > +#define APP_LTSSM_ENABLE BIT(0) > + > +#define RCAR_NUM_SPEED_CHANGE_RETRIES 10 > +#define RCAR_MAX_LINK_SPEED 4 > + > +static void rcar_gen4_pcie_ltssm_enable(struct rcar_gen4_pcie *rcar, > + bool enable) > +{ > + u32 val; > + > + val = readl(rcar->base + PCIERSTCTRL1); > + if (enable) { > + val |= APP_LTSSM_ENABLE; > + val &= ~APP_HOLD_PHY_RST; > + } else { > + /* > + * Since the datasheet of R-Car doesn't mention how to assert > + * the APP_HOLD_PHY_RST, don't assert it again. Otherwise, > + * hang-up issue happened in the dw_edma_core_off() when > + * the controller didn't detect a PCI device. > + */ > + val &= ~APP_LTSSM_ENABLE; > + } > + writel(val, rcar->base + PCIERSTCTRL1); > +} > + > +static int rcar_gen4_pcie_link_up(struct dw_pcie *dw) > +{ > + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); > + u32 val, mask; > + > + val = readl(rcar->base + PCIEINTSTS0); > + mask = RDLH_LINK_UP | SMLH_LINK_UP; > + > + return (val & mask) == mask; > +} > + > +/* > + * Manually initiate the speed change. Return true if the change succeeded, > + * false if the change didn't finish within certain periods. > + */ > +static bool rcar_gen4_pcie_speed_change(struct dw_pcie *dw) > +{ > + u32 val; > + int i; > + > + val = dw_pcie_readl_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL); > + val &= ~PORT_LOGIC_SPEED_CHANGE; > + dw_pcie_writel_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL, val); > + > + val = dw_pcie_readl_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL); > + val |= PORT_LOGIC_SPEED_CHANGE; > + dw_pcie_writel_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL, val); > + > + for (i = 0; i < RCAR_NUM_SPEED_CHANGE_RETRIES; i++) { > + val = dw_pcie_readl_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL); > + if (!(val & PORT_LOGIC_SPEED_CHANGE)) > + return true; > + usleep_range(10000, 11000); > + } > + > + return false; > +} > + > +/* > + * Enable LTSSM of this controller and manually initiate the speed change. > + * Always return true. > + */ > +static int rcar_gen4_pcie_start_link(struct dw_pcie *dw) > +{ > + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); > + int i, changes; > + > + rcar_gen4_pcie_ltssm_enable(rcar, true); > + > + /* > + * Require direct speed change with retrying here if the link_gen is > + * PCIe Gen2 or higher. > + */ > + changes = min_not_zero(dw->link_gen, RCAR_MAX_LINK_SPEED) - 1; > + > + /* > + * Since dw_pcie_setup_rc() sets it once, PCIe Gen2 will be trained. > + * So, this needs remaining times for up to PCIe Gen4 if RC mode. > + */ > + if (changes && rcar->mode == DW_PCIE_RC_TYPE) > + changes--; > + > + for (i = 0; i < changes; i++) { > + if (!rcar_gen4_pcie_speed_change(dw)) > + break; /* No error because possible disconnected here if EP mode */ > + } > + > + return 0; > +} > + > +static void rcar_gen4_pcie_stop_link(struct dw_pcie *dw) > +{ > + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); > + > + rcar_gen4_pcie_ltssm_enable(rcar, false); > +} > + > +int rcar_gen4_pcie_common_init(struct rcar_gen4_pcie *rcar) > +{ > + struct dw_pcie *dw = &rcar->dw; > + u32 val; > + > + if (!reset_control_status(dw->core_rsts[DW_PCIE_PWR_RST].rstc)) > + reset_control_assert(dw->core_rsts[DW_PCIE_PWR_RST].rstc); > + > + val = readl(rcar->base + PCIEMSR0); > + if (rcar->mode == DW_PCIE_RC_TYPE) > + val |= DEVICE_TYPE_RC; > + else if (rcar->mode == DW_PCIE_EP_TYPE) > + val |= DEVICE_TYPE_EP; > + else > + return -EINVAL; > + > + if (dw->num_lanes < 4) > + val |= BIFUR_MOD_SET_ON; > + > + writel(val, rcar->base + PCIEMSR0); > + > + return reset_control_deassert(dw->core_rsts[DW_PCIE_PWR_RST].rstc); > +} > + > +void rcar_gen4_pcie_common_deinit(struct rcar_gen4_pcie *rcar) > +{ > + struct dw_pcie *dw = &rcar->dw; > + > + reset_control_assert(dw->core_rsts[DW_PCIE_PWR_RST].rstc); > +} > + > +int rcar_gen4_pcie_prepare(struct rcar_gen4_pcie *rcar) > +{ > + struct device *dev = rcar->dw.dev; > + int err; > + > + pm_runtime_enable(dev); > + err = pm_runtime_resume_and_get(dev); > + if (err < 0) { > + dev_err(dev, "Failed to resume/get Runtime PM\n"); > + pm_runtime_disable(dev); > + } > + > + return err; > +} > + > +void rcar_gen4_pcie_unprepare(struct rcar_gen4_pcie *rcar) > +{ > + struct device *dev = rcar->dw.dev; > + > + pm_runtime_put(dev); > + pm_runtime_disable(dev); > +} > + > +int rcar_gen4_pcie_get_resources(struct rcar_gen4_pcie *rcar) > +{ > + /* Renesas-specific registers */ > + rcar->base = devm_platform_ioremap_resource_byname(rcar->pdev, "app"); > + > + return PTR_ERR_OR_ZERO(rcar->base); > +} > + > +static const struct dw_pcie_ops dw_pcie_ops = { > + .start_link = rcar_gen4_pcie_start_link, > + .stop_link = rcar_gen4_pcie_stop_link, > + .link_up = rcar_gen4_pcie_link_up, > +}; > + > +struct rcar_gen4_pcie *rcar_gen4_pcie_devm_alloc(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct rcar_gen4_pcie *rcar; > + > + rcar = devm_kzalloc(dev, sizeof(*rcar), GFP_KERNEL); > + if (!rcar) > + return ERR_PTR(-ENOMEM); > + > + rcar->dw.ops = &dw_pcie_ops; > + rcar->dw.dev = dev; > + rcar->pdev = pdev; > + dw_pcie_cap_set(&rcar->dw, EDMA_UNROLL); > + dw_pcie_cap_set(&rcar->dw, REQ_RES); > + platform_set_drvdata(pdev, rcar); > + > + return rcar; > +} > diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.h b/drivers/pci/controller/dwc/pcie-rcar-gen4.h > new file mode 100644 > index 000000000000..7cbb3767c2d4 > --- /dev/null > +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.h > @@ -0,0 +1,44 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * PCIe host/endpoint controller driver for Renesas R-Car Gen4 Series SoCs > + * Copyright (C) 2022-2023 Renesas Electronics Corporation > + */ > + > +#ifndef _PCIE_RCAR_GEN4_H_ > +#define _PCIE_RCAR_GEN4_H_ > + > +#include <linux/io.h> > +#include <linux/pci.h> > + > +#include "pcie-designware.h" > + > +/* Renesas-specific */ > +#define PCIEMSR0 0x0000 > +#define BIFUR_MOD_SET_ON BIT(0) > +#define DEVICE_TYPE_EP 0 > +#define DEVICE_TYPE_RC BIT(4) > + > +#define PCIEINTSTS0 0x0084 > +#define PCIEINTSTS0EN 0x0310 > +#define MSI_CTRL_INT BIT(26) > +#define SMLH_LINK_UP BIT(7) > +#define RDLH_LINK_UP BIT(6) > +#define PCIEDMAINTSTSEN 0x0314 > +#define PCIEDMAINTSTSEN_INIT GENMASK(15, 0) > + > +struct rcar_gen4_pcie { > + struct dw_pcie dw; > + void __iomem *base; > + struct platform_device *pdev; > + enum dw_pcie_device_mode mode; > +}; > +#define to_rcar_gen4_pcie(_dw) container_of(_dw, struct rcar_gen4_pcie, dw) > + > +int rcar_gen4_pcie_common_init(struct rcar_gen4_pcie *rcar); > +void rcar_gen4_pcie_common_deinit(struct rcar_gen4_pcie *rcar); > +int rcar_gen4_pcie_prepare(struct rcar_gen4_pcie *rcar); > +void rcar_gen4_pcie_unprepare(struct rcar_gen4_pcie *rcar); > +int rcar_gen4_pcie_get_resources(struct rcar_gen4_pcie *rcar); > +struct rcar_gen4_pcie *rcar_gen4_pcie_devm_alloc(struct platform_device *pdev); > + > +#endif /* _PCIE_RCAR_GEN4_H_ */ > -- > 2.25.1 >
Hello Serge, > From: Serge Semin, Sent: Wednesday, August 23, 2023 8:56 PM > > On Wed, Aug 23, 2023 at 06:11:50PM +0900, Yoshihiro Shimoda wrote: > > Add R-Car Gen4 PCIe Host support. This controller is based on > > Synopsys DesignWare PCIe, but this controller has vendor-specific > > registers so that requires initialization code like mode setting > > and retraining and so on. > > > > To reduce code delta, adds some helper functions which are used by > > both the host driver and the endpoint driver (which is added > > immediately afterwards) into a separate file. > > > > Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> > > --- > > drivers/pci/controller/dwc/Kconfig | 10 + > > drivers/pci/controller/dwc/Makefile | 2 + > > .../controller/dwc/pcie-rcar-gen4-host-drv.c | 145 ++++++++++++ > > drivers/pci/controller/dwc/pcie-rcar-gen4.c | 208 ++++++++++++++++++ > > drivers/pci/controller/dwc/pcie-rcar-gen4.h | 44 ++++ > > 5 files changed, 409 insertions(+) > > create mode 100644 drivers/pci/controller/dwc/pcie-rcar-gen4-host-drv.c > > create mode 100644 drivers/pci/controller/dwc/pcie-rcar-gen4.c > > create mode 100644 drivers/pci/controller/dwc/pcie-rcar-gen4.h > > > > diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig > > index ab96da43e0c2..3884a67e4d56 100644 > > --- a/drivers/pci/controller/dwc/Kconfig > > +++ b/drivers/pci/controller/dwc/Kconfig > > @@ -415,4 +415,14 @@ config PCIE_VISCONTI_HOST > > Say Y here if you want PCIe controller support on Toshiba Visconti SoC. > > This driver supports TMPV7708 SoC. > > > > +config PCIE_RCAR_GEN4 > > + tristate "Renesas R-Car Gen4 PCIe Host controller" > > + depends on ARCH_RENESAS || COMPILE_TEST > > + depends on PCI_MSI > > + select PCIE_DW_HOST > > + help > > + Say Y here if you want PCIe host controller support on R-Car Gen4 SoCs. > > + To compile this driver as a module, choose M here: the module will be > > + called pcie-rcar-gen4-host.ko. This uses the DesignWare core. > > + > > endmenu > > diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile > > index bf5c311875a1..ab2c6bc16216 100644 > > --- a/drivers/pci/controller/dwc/Makefile > > +++ b/drivers/pci/controller/dwc/Makefile > > @@ -26,6 +26,8 @@ obj-$(CONFIG_PCIE_TEGRA194) += pcie-tegra194.o > > obj-$(CONFIG_PCIE_UNIPHIER) += pcie-uniphier.o > > obj-$(CONFIG_PCIE_UNIPHIER_EP) += pcie-uniphier-ep.o > > obj-$(CONFIG_PCIE_VISCONTI_HOST) += pcie-visconti.o > > +pcie-rcar-gen4-host-objs := pcie-rcar-gen4.o pcie-rcar-gen4-host-drv.o > > +obj-$(CONFIG_PCIE_RCAR_GEN4) += pcie-rcar-gen4-host.o > > > > # The following drivers are for devices that use the generic ACPI > > # pci_root.c driver but don't support standard ECAM config access. > > diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4-host-drv.c > b/drivers/pci/controller/dwc/pcie-rcar-gen4-host-drv.c > > new file mode 100644 > > index 000000000000..8acce1ee5efc > > --- /dev/null > > +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4-host-drv.c > > @@ -0,0 +1,145 @@ > > +// SPDX-License-Identifier: GPL-2.0-only > > +/* > > + * PCIe host controller driver for Renesas R-Car Gen4 Series SoCs > > + * Copyright (C) 2022-2023 Renesas Electronics Corporation > > + */ > > + > > +#include <linux/delay.h> > > +#include <linux/interrupt.h> > > +#include <linux/module.h> > > +#include <linux/of_device.h> > > +#include <linux/pci.h> > > +#include <linux/platform_device.h> > > + > > +#include "pcie-rcar-gen4.h" > > +#include "pcie-designware.h" > > + > > +static int rcar_gen4_pcie_host_init(struct dw_pcie_rp *pp) > > +{ > > + struct dw_pcie *dw = to_dw_pcie_from_pp(pp); > > + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); > > + int ret; > > + u32 val; > > + > > + gpiod_set_value_cansleep(dw->pe_rst, 1); > > + > > > + ret = clk_bulk_prepare_enable(DW_PCIE_NUM_CORE_CLKS, dw->core_clks); > > + if (ret) { > > + dev_err(dw->dev, "Failed to enable ref clocks\n"); > > + return ret; > > + } > > This is called in both the Host and End-point init function right > above the rcar_gen4_pcie_common_init() method invocation. It can be moved > there then. I got it. > > + > > + ret = rcar_gen4_pcie_common_init(rcar); > > + if (ret) { > > + clk_bulk_disable_unprepare(DW_PCIE_NUM_CORE_CLKS, dw->core_clks); > > + return ret; > > + } > > + > > + /* > > + * According to the section 3.5.7.2 "RC Mode" in DWC PCIe Dual Mode > > + * Rev.5.20a, we should disable two BARs to avoid unnecessary memory > > + * assignment during device enumeration. > > + */ > > + dw_pcie_writel_dbi2(dw, PCI_BASE_ADDRESS_0, 0x0); > > + dw_pcie_writel_dbi2(dw, PCI_BASE_ADDRESS_1, 0x0); > > + > > + /* Enable MSI interrupt signal */ > > + val = readl(rcar->base + PCIEINTSTS0EN); > > + val |= MSI_CTRL_INT; > > + writel(val, rcar->base + PCIEINTSTS0EN); > > + > > + msleep(100); /* pe_rst requires 100msec delay */ > > + > > + gpiod_set_value_cansleep(dw->pe_rst, 0); > > + > > + return 0; > > +} > > + > > +static void rcar_gen4_pcie_host_deinit(struct dw_pcie_rp *pp) > > +{ > > + struct dw_pcie *dw = to_dw_pcie_from_pp(pp); > > + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); > > + > > + gpiod_set_value_cansleep(dw->pe_rst, 1); > > + rcar_gen4_pcie_common_deinit(rcar); > > > + clk_bulk_disable_unprepare(DW_PCIE_NUM_CORE_CLKS, dw->core_clks); > > and this can be moved to rcar_gen4_pcie_common_deinit() too for > the same reason as denoted in the previous comment. I got it. > > +} > > + > > +static const struct dw_pcie_host_ops rcar_gen4_pcie_host_ops = { > > + .host_init = rcar_gen4_pcie_host_init, > > + .host_deinit = rcar_gen4_pcie_host_deinit, > > +}; > > + > > +static int rcar_gen4_add_dw_pcie_rp(struct rcar_gen4_pcie *rcar) > > +{ > > + struct dw_pcie_rp *pp = &rcar->dw.pp; > > + > > + pp->num_vectors = MAX_MSI_IRQS; > > + pp->ops = &rcar_gen4_pcie_host_ops; > > + rcar->mode = DW_PCIE_RC_TYPE; > > + > > + return dw_pcie_host_init(pp); > > +} > > + > > +static void rcar_gen4_remove_dw_pcie_rp(struct rcar_gen4_pcie *rcar) > > +{ > > > + dw_pcie_host_deinit(&rcar->dw.pp); > > + gpiod_set_value_cansleep(rcar->dw.pe_rst, 1); > > gpiod_set_value_cansleep() seems redundant here because > dw_pcie_host_deinit() calls host_deinit() which is > rcar_gen4_pcie_host_deinit() and which already asserts the PE_RST > GPIO. I got it. I'll drop this on v20. > BTW even though after dropping the gpiod_set_value_cansleep() function > call from rcar_gen4_remove_dw_pcie_rp(), the later will be left with > only a single function invocation I would have left it defined anyway > for the internal driver interface consistency and maintainability: > you'll have a protagonist and respective antagonist defined in a way > it's done for host_init()/host_deinit(), > common_init()/common_deinit(), prepare()/unprepare(), etc. In addition > such design would simplify possible updates should you need to > extend rcar_gen4_add_dw_pcie_rp() functionality and add new cleanups > afterwards. I think so. > > +} > > + > > +static int rcar_gen4_pcie_probe(struct platform_device *pdev) > > +{ > > + struct rcar_gen4_pcie *rcar; > > + int err; > > + > > + rcar = rcar_gen4_pcie_devm_alloc(pdev); > > + if (IS_ERR(rcar)) > > + return PTR_ERR(rcar); > > + > > + err = rcar_gen4_pcie_get_resources(rcar); > > + if (err) > > + return err; > > + > > + err = rcar_gen4_pcie_prepare(rcar); > > + if (err) > > + return err; > > + > > + err = rcar_gen4_add_dw_pcie_rp(rcar); > > + if (err) > > + goto err_unprepare; > > + > > + return 0; > > + > > +err_unprepare: > > + rcar_gen4_pcie_unprepare(rcar); > > + > > + return err; > > +} > > Look how neat and beautiful the probe() method is now. So is the rest > of the driver.) So to speak with the previous notes fixed feel free to > add: Thank you very much for your support! > Reviewed-by: Serge Semin <fancer.lancer@gmail.com> Thank you for your review! Best regards, Yoshihiro Shimoda > -Serge(y) > > > + > > +static void rcar_gen4_pcie_remove(struct platform_device *pdev) > > +{ > > + struct rcar_gen4_pcie *rcar = platform_get_drvdata(pdev); > > + > > + rcar_gen4_remove_dw_pcie_rp(rcar); > > + rcar_gen4_pcie_unprepare(rcar); > > +} > > + > > +static const struct of_device_id rcar_gen4_pcie_of_match[] = { > > + { .compatible = "renesas,rcar-gen4-pcie", }, > > + {}, > > +}; > > +MODULE_DEVICE_TABLE(of, rcar_gen4_pcie_of_match); > > + > > +static struct platform_driver rcar_gen4_pcie_driver = { > > + .driver = { > > + .name = "pcie-rcar-gen4", > > + .of_match_table = rcar_gen4_pcie_of_match, > > + .probe_type = PROBE_PREFER_ASYNCHRONOUS, > > + }, > > + .probe = rcar_gen4_pcie_probe, > > + .remove_new = rcar_gen4_pcie_remove, > > +}; > > +module_platform_driver(rcar_gen4_pcie_driver); > > + > > +MODULE_DESCRIPTION("Renesas R-Car Gen4 PCIe host controller driver"); > > +MODULE_LICENSE("GPL"); > > diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c > > new file mode 100644 > > index 000000000000..2a8bbf928d5f > > --- /dev/null > > +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c > > @@ -0,0 +1,208 @@ > > +// SPDX-License-Identifier: GPL-2.0-only > > +/* > > + * PCIe host/endpoint controller driver for Renesas R-Car Gen4 Series SoCs > > + * Copyright (C) 2022-2023 Renesas Electronics Corporation > > + */ > > + > > +#include <linux/delay.h> > > +#include <linux/io.h> > > +#include <linux/of_device.h> > > +#include <linux/pci.h> > > +#include <linux/pm_runtime.h> > > +#include <linux/reset.h> > > + > > +#include "pcie-rcar-gen4.h" > > +#include "pcie-designware.h" > > + > > +/* Renesas-specific */ > > +#define PCIERSTCTRL1 0x0014 > > +#define APP_HOLD_PHY_RST BIT(16) > > +#define APP_LTSSM_ENABLE BIT(0) > > + > > +#define RCAR_NUM_SPEED_CHANGE_RETRIES 10 > > +#define RCAR_MAX_LINK_SPEED 4 > > + > > +static void rcar_gen4_pcie_ltssm_enable(struct rcar_gen4_pcie *rcar, > > + bool enable) > > +{ > > + u32 val; > > + > > + val = readl(rcar->base + PCIERSTCTRL1); > > + if (enable) { > > + val |= APP_LTSSM_ENABLE; > > + val &= ~APP_HOLD_PHY_RST; > > + } else { > > + /* > > + * Since the datasheet of R-Car doesn't mention how to assert > > + * the APP_HOLD_PHY_RST, don't assert it again. Otherwise, > > + * hang-up issue happened in the dw_edma_core_off() when > > + * the controller didn't detect a PCI device. > > + */ > > + val &= ~APP_LTSSM_ENABLE; > > + } > > + writel(val, rcar->base + PCIERSTCTRL1); > > +} > > + > > +static int rcar_gen4_pcie_link_up(struct dw_pcie *dw) > > +{ > > + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); > > + u32 val, mask; > > + > > + val = readl(rcar->base + PCIEINTSTS0); > > + mask = RDLH_LINK_UP | SMLH_LINK_UP; > > + > > + return (val & mask) == mask; > > +} > > + > > +/* > > + * Manually initiate the speed change. Return true if the change succeeded, > > + * false if the change didn't finish within certain periods. > > + */ > > +static bool rcar_gen4_pcie_speed_change(struct dw_pcie *dw) > > +{ > > + u32 val; > > + int i; > > + > > + val = dw_pcie_readl_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL); > > + val &= ~PORT_LOGIC_SPEED_CHANGE; > > + dw_pcie_writel_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL, val); > > + > > + val = dw_pcie_readl_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL); > > + val |= PORT_LOGIC_SPEED_CHANGE; > > + dw_pcie_writel_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL, val); > > + > > + for (i = 0; i < RCAR_NUM_SPEED_CHANGE_RETRIES; i++) { > > + val = dw_pcie_readl_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL); > > + if (!(val & PORT_LOGIC_SPEED_CHANGE)) > > + return true; > > + usleep_range(10000, 11000); > > + } > > + > > + return false; > > +} > > + > > +/* > > + * Enable LTSSM of this controller and manually initiate the speed change. > > + * Always return true. > > + */ > > +static int rcar_gen4_pcie_start_link(struct dw_pcie *dw) > > +{ > > + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); > > + int i, changes; > > + > > + rcar_gen4_pcie_ltssm_enable(rcar, true); > > + > > + /* > > + * Require direct speed change with retrying here if the link_gen is > > + * PCIe Gen2 or higher. > > + */ > > + changes = min_not_zero(dw->link_gen, RCAR_MAX_LINK_SPEED) - 1; > > + > > + /* > > + * Since dw_pcie_setup_rc() sets it once, PCIe Gen2 will be trained. > > + * So, this needs remaining times for up to PCIe Gen4 if RC mode. > > + */ > > + if (changes && rcar->mode == DW_PCIE_RC_TYPE) > > + changes--; > > + > > + for (i = 0; i < changes; i++) { > > + if (!rcar_gen4_pcie_speed_change(dw)) > > + break; /* No error because possible disconnected here if EP mode */ > > + } > > + > > + return 0; > > +} > > + > > +static void rcar_gen4_pcie_stop_link(struct dw_pcie *dw) > > +{ > > + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); > > + > > + rcar_gen4_pcie_ltssm_enable(rcar, false); > > +} > > + > > +int rcar_gen4_pcie_common_init(struct rcar_gen4_pcie *rcar) > > +{ > > + struct dw_pcie *dw = &rcar->dw; > > + u32 val; > > + > > + if (!reset_control_status(dw->core_rsts[DW_PCIE_PWR_RST].rstc)) > > + reset_control_assert(dw->core_rsts[DW_PCIE_PWR_RST].rstc); > > + > > + val = readl(rcar->base + PCIEMSR0); > > + if (rcar->mode == DW_PCIE_RC_TYPE) > > + val |= DEVICE_TYPE_RC; > > + else if (rcar->mode == DW_PCIE_EP_TYPE) > > + val |= DEVICE_TYPE_EP; > > + else > > + return -EINVAL; > > + > > + if (dw->num_lanes < 4) > > + val |= BIFUR_MOD_SET_ON; > > + > > + writel(val, rcar->base + PCIEMSR0); > > + > > + return reset_control_deassert(dw->core_rsts[DW_PCIE_PWR_RST].rstc); > > +} > > + > > +void rcar_gen4_pcie_common_deinit(struct rcar_gen4_pcie *rcar) > > +{ > > + struct dw_pcie *dw = &rcar->dw; > > + > > + reset_control_assert(dw->core_rsts[DW_PCIE_PWR_RST].rstc); > > +} > > + > > +int rcar_gen4_pcie_prepare(struct rcar_gen4_pcie *rcar) > > +{ > > + struct device *dev = rcar->dw.dev; > > + int err; > > + > > + pm_runtime_enable(dev); > > + err = pm_runtime_resume_and_get(dev); > > + if (err < 0) { > > + dev_err(dev, "Failed to resume/get Runtime PM\n"); > > + pm_runtime_disable(dev); > > + } > > + > > + return err; > > +} > > + > > +void rcar_gen4_pcie_unprepare(struct rcar_gen4_pcie *rcar) > > +{ > > + struct device *dev = rcar->dw.dev; > > + > > + pm_runtime_put(dev); > > + pm_runtime_disable(dev); > > +} > > + > > +int rcar_gen4_pcie_get_resources(struct rcar_gen4_pcie *rcar) > > +{ > > + /* Renesas-specific registers */ > > + rcar->base = devm_platform_ioremap_resource_byname(rcar->pdev, "app"); > > + > > + return PTR_ERR_OR_ZERO(rcar->base); > > +} > > + > > +static const struct dw_pcie_ops dw_pcie_ops = { > > + .start_link = rcar_gen4_pcie_start_link, > > + .stop_link = rcar_gen4_pcie_stop_link, > > + .link_up = rcar_gen4_pcie_link_up, > > +}; > > + > > +struct rcar_gen4_pcie *rcar_gen4_pcie_devm_alloc(struct platform_device *pdev) > > +{ > > + struct device *dev = &pdev->dev; > > + struct rcar_gen4_pcie *rcar; > > + > > + rcar = devm_kzalloc(dev, sizeof(*rcar), GFP_KERNEL); > > + if (!rcar) > > + return ERR_PTR(-ENOMEM); > > + > > + rcar->dw.ops = &dw_pcie_ops; > > + rcar->dw.dev = dev; > > + rcar->pdev = pdev; > > + dw_pcie_cap_set(&rcar->dw, EDMA_UNROLL); > > + dw_pcie_cap_set(&rcar->dw, REQ_RES); > > + platform_set_drvdata(pdev, rcar); > > + > > + return rcar; > > +} > > diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.h b/drivers/pci/controller/dwc/pcie-rcar-gen4.h > > new file mode 100644 > > index 000000000000..7cbb3767c2d4 > > --- /dev/null > > +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.h > > @@ -0,0 +1,44 @@ > > +/* SPDX-License-Identifier: GPL-2.0-only */ > > +/* > > + * PCIe host/endpoint controller driver for Renesas R-Car Gen4 Series SoCs > > + * Copyright (C) 2022-2023 Renesas Electronics Corporation > > + */ > > + > > +#ifndef _PCIE_RCAR_GEN4_H_ > > +#define _PCIE_RCAR_GEN4_H_ > > + > > +#include <linux/io.h> > > +#include <linux/pci.h> > > + > > +#include "pcie-designware.h" > > + > > +/* Renesas-specific */ > > +#define PCIEMSR0 0x0000 > > +#define BIFUR_MOD_SET_ON BIT(0) > > +#define DEVICE_TYPE_EP 0 > > +#define DEVICE_TYPE_RC BIT(4) > > + > > +#define PCIEINTSTS0 0x0084 > > +#define PCIEINTSTS0EN 0x0310 > > +#define MSI_CTRL_INT BIT(26) > > +#define SMLH_LINK_UP BIT(7) > > +#define RDLH_LINK_UP BIT(6) > > +#define PCIEDMAINTSTSEN 0x0314 > > +#define PCIEDMAINTSTSEN_INIT GENMASK(15, 0) > > + > > +struct rcar_gen4_pcie { > > + struct dw_pcie dw; > > + void __iomem *base; > > + struct platform_device *pdev; > > + enum dw_pcie_device_mode mode; > > +}; > > +#define to_rcar_gen4_pcie(_dw) container_of(_dw, struct rcar_gen4_pcie, dw) > > + > > +int rcar_gen4_pcie_common_init(struct rcar_gen4_pcie *rcar); > > +void rcar_gen4_pcie_common_deinit(struct rcar_gen4_pcie *rcar); > > +int rcar_gen4_pcie_prepare(struct rcar_gen4_pcie *rcar); > > +void rcar_gen4_pcie_unprepare(struct rcar_gen4_pcie *rcar); > > +int rcar_gen4_pcie_get_resources(struct rcar_gen4_pcie *rcar); > > +struct rcar_gen4_pcie *rcar_gen4_pcie_devm_alloc(struct platform_device *pdev); > > + > > +#endif /* _PCIE_RCAR_GEN4_H_ */ > > -- > > 2.25.1 > >
diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig index ab96da43e0c2..3884a67e4d56 100644 --- a/drivers/pci/controller/dwc/Kconfig +++ b/drivers/pci/controller/dwc/Kconfig @@ -415,4 +415,14 @@ config PCIE_VISCONTI_HOST Say Y here if you want PCIe controller support on Toshiba Visconti SoC. This driver supports TMPV7708 SoC. +config PCIE_RCAR_GEN4 + tristate "Renesas R-Car Gen4 PCIe Host controller" + depends on ARCH_RENESAS || COMPILE_TEST + depends on PCI_MSI + select PCIE_DW_HOST + help + Say Y here if you want PCIe host controller support on R-Car Gen4 SoCs. + To compile this driver as a module, choose M here: the module will be + called pcie-rcar-gen4-host.ko. This uses the DesignWare core. + endmenu diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile index bf5c311875a1..ab2c6bc16216 100644 --- a/drivers/pci/controller/dwc/Makefile +++ b/drivers/pci/controller/dwc/Makefile @@ -26,6 +26,8 @@ obj-$(CONFIG_PCIE_TEGRA194) += pcie-tegra194.o obj-$(CONFIG_PCIE_UNIPHIER) += pcie-uniphier.o obj-$(CONFIG_PCIE_UNIPHIER_EP) += pcie-uniphier-ep.o obj-$(CONFIG_PCIE_VISCONTI_HOST) += pcie-visconti.o +pcie-rcar-gen4-host-objs := pcie-rcar-gen4.o pcie-rcar-gen4-host-drv.o +obj-$(CONFIG_PCIE_RCAR_GEN4) += pcie-rcar-gen4-host.o # The following drivers are for devices that use the generic ACPI # pci_root.c driver but don't support standard ECAM config access. diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4-host-drv.c b/drivers/pci/controller/dwc/pcie-rcar-gen4-host-drv.c new file mode 100644 index 000000000000..8acce1ee5efc --- /dev/null +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4-host-drv.c @@ -0,0 +1,145 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * PCIe host controller driver for Renesas R-Car Gen4 Series SoCs + * Copyright (C) 2022-2023 Renesas Electronics Corporation + */ + +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/pci.h> +#include <linux/platform_device.h> + +#include "pcie-rcar-gen4.h" +#include "pcie-designware.h" + +static int rcar_gen4_pcie_host_init(struct dw_pcie_rp *pp) +{ + struct dw_pcie *dw = to_dw_pcie_from_pp(pp); + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); + int ret; + u32 val; + + gpiod_set_value_cansleep(dw->pe_rst, 1); + + ret = clk_bulk_prepare_enable(DW_PCIE_NUM_CORE_CLKS, dw->core_clks); + if (ret) { + dev_err(dw->dev, "Failed to enable ref clocks\n"); + return ret; + } + + ret = rcar_gen4_pcie_common_init(rcar); + if (ret) { + clk_bulk_disable_unprepare(DW_PCIE_NUM_CORE_CLKS, dw->core_clks); + return ret; + } + + /* + * According to the section 3.5.7.2 "RC Mode" in DWC PCIe Dual Mode + * Rev.5.20a, we should disable two BARs to avoid unnecessary memory + * assignment during device enumeration. + */ + dw_pcie_writel_dbi2(dw, PCI_BASE_ADDRESS_0, 0x0); + dw_pcie_writel_dbi2(dw, PCI_BASE_ADDRESS_1, 0x0); + + /* Enable MSI interrupt signal */ + val = readl(rcar->base + PCIEINTSTS0EN); + val |= MSI_CTRL_INT; + writel(val, rcar->base + PCIEINTSTS0EN); + + msleep(100); /* pe_rst requires 100msec delay */ + + gpiod_set_value_cansleep(dw->pe_rst, 0); + + return 0; +} + +static void rcar_gen4_pcie_host_deinit(struct dw_pcie_rp *pp) +{ + struct dw_pcie *dw = to_dw_pcie_from_pp(pp); + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); + + gpiod_set_value_cansleep(dw->pe_rst, 1); + rcar_gen4_pcie_common_deinit(rcar); + clk_bulk_disable_unprepare(DW_PCIE_NUM_CORE_CLKS, dw->core_clks); +} + +static const struct dw_pcie_host_ops rcar_gen4_pcie_host_ops = { + .host_init = rcar_gen4_pcie_host_init, + .host_deinit = rcar_gen4_pcie_host_deinit, +}; + +static int rcar_gen4_add_dw_pcie_rp(struct rcar_gen4_pcie *rcar) +{ + struct dw_pcie_rp *pp = &rcar->dw.pp; + + pp->num_vectors = MAX_MSI_IRQS; + pp->ops = &rcar_gen4_pcie_host_ops; + rcar->mode = DW_PCIE_RC_TYPE; + + return dw_pcie_host_init(pp); +} + +static void rcar_gen4_remove_dw_pcie_rp(struct rcar_gen4_pcie *rcar) +{ + dw_pcie_host_deinit(&rcar->dw.pp); + gpiod_set_value_cansleep(rcar->dw.pe_rst, 1); +} + +static int rcar_gen4_pcie_probe(struct platform_device *pdev) +{ + struct rcar_gen4_pcie *rcar; + int err; + + rcar = rcar_gen4_pcie_devm_alloc(pdev); + if (IS_ERR(rcar)) + return PTR_ERR(rcar); + + err = rcar_gen4_pcie_get_resources(rcar); + if (err) + return err; + + err = rcar_gen4_pcie_prepare(rcar); + if (err) + return err; + + err = rcar_gen4_add_dw_pcie_rp(rcar); + if (err) + goto err_unprepare; + + return 0; + +err_unprepare: + rcar_gen4_pcie_unprepare(rcar); + + return err; +} + +static void rcar_gen4_pcie_remove(struct platform_device *pdev) +{ + struct rcar_gen4_pcie *rcar = platform_get_drvdata(pdev); + + rcar_gen4_remove_dw_pcie_rp(rcar); + rcar_gen4_pcie_unprepare(rcar); +} + +static const struct of_device_id rcar_gen4_pcie_of_match[] = { + { .compatible = "renesas,rcar-gen4-pcie", }, + {}, +}; +MODULE_DEVICE_TABLE(of, rcar_gen4_pcie_of_match); + +static struct platform_driver rcar_gen4_pcie_driver = { + .driver = { + .name = "pcie-rcar-gen4", + .of_match_table = rcar_gen4_pcie_of_match, + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + }, + .probe = rcar_gen4_pcie_probe, + .remove_new = rcar_gen4_pcie_remove, +}; +module_platform_driver(rcar_gen4_pcie_driver); + +MODULE_DESCRIPTION("Renesas R-Car Gen4 PCIe host controller driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c new file mode 100644 index 000000000000..2a8bbf928d5f --- /dev/null +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c @@ -0,0 +1,208 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * PCIe host/endpoint controller driver for Renesas R-Car Gen4 Series SoCs + * Copyright (C) 2022-2023 Renesas Electronics Corporation + */ + +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/of_device.h> +#include <linux/pci.h> +#include <linux/pm_runtime.h> +#include <linux/reset.h> + +#include "pcie-rcar-gen4.h" +#include "pcie-designware.h" + +/* Renesas-specific */ +#define PCIERSTCTRL1 0x0014 +#define APP_HOLD_PHY_RST BIT(16) +#define APP_LTSSM_ENABLE BIT(0) + +#define RCAR_NUM_SPEED_CHANGE_RETRIES 10 +#define RCAR_MAX_LINK_SPEED 4 + +static void rcar_gen4_pcie_ltssm_enable(struct rcar_gen4_pcie *rcar, + bool enable) +{ + u32 val; + + val = readl(rcar->base + PCIERSTCTRL1); + if (enable) { + val |= APP_LTSSM_ENABLE; + val &= ~APP_HOLD_PHY_RST; + } else { + /* + * Since the datasheet of R-Car doesn't mention how to assert + * the APP_HOLD_PHY_RST, don't assert it again. Otherwise, + * hang-up issue happened in the dw_edma_core_off() when + * the controller didn't detect a PCI device. + */ + val &= ~APP_LTSSM_ENABLE; + } + writel(val, rcar->base + PCIERSTCTRL1); +} + +static int rcar_gen4_pcie_link_up(struct dw_pcie *dw) +{ + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); + u32 val, mask; + + val = readl(rcar->base + PCIEINTSTS0); + mask = RDLH_LINK_UP | SMLH_LINK_UP; + + return (val & mask) == mask; +} + +/* + * Manually initiate the speed change. Return true if the change succeeded, + * false if the change didn't finish within certain periods. + */ +static bool rcar_gen4_pcie_speed_change(struct dw_pcie *dw) +{ + u32 val; + int i; + + val = dw_pcie_readl_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL); + val &= ~PORT_LOGIC_SPEED_CHANGE; + dw_pcie_writel_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL, val); + + val = dw_pcie_readl_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL); + val |= PORT_LOGIC_SPEED_CHANGE; + dw_pcie_writel_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL, val); + + for (i = 0; i < RCAR_NUM_SPEED_CHANGE_RETRIES; i++) { + val = dw_pcie_readl_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL); + if (!(val & PORT_LOGIC_SPEED_CHANGE)) + return true; + usleep_range(10000, 11000); + } + + return false; +} + +/* + * Enable LTSSM of this controller and manually initiate the speed change. + * Always return true. + */ +static int rcar_gen4_pcie_start_link(struct dw_pcie *dw) +{ + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); + int i, changes; + + rcar_gen4_pcie_ltssm_enable(rcar, true); + + /* + * Require direct speed change with retrying here if the link_gen is + * PCIe Gen2 or higher. + */ + changes = min_not_zero(dw->link_gen, RCAR_MAX_LINK_SPEED) - 1; + + /* + * Since dw_pcie_setup_rc() sets it once, PCIe Gen2 will be trained. + * So, this needs remaining times for up to PCIe Gen4 if RC mode. + */ + if (changes && rcar->mode == DW_PCIE_RC_TYPE) + changes--; + + for (i = 0; i < changes; i++) { + if (!rcar_gen4_pcie_speed_change(dw)) + break; /* No error because possible disconnected here if EP mode */ + } + + return 0; +} + +static void rcar_gen4_pcie_stop_link(struct dw_pcie *dw) +{ + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); + + rcar_gen4_pcie_ltssm_enable(rcar, false); +} + +int rcar_gen4_pcie_common_init(struct rcar_gen4_pcie *rcar) +{ + struct dw_pcie *dw = &rcar->dw; + u32 val; + + if (!reset_control_status(dw->core_rsts[DW_PCIE_PWR_RST].rstc)) + reset_control_assert(dw->core_rsts[DW_PCIE_PWR_RST].rstc); + + val = readl(rcar->base + PCIEMSR0); + if (rcar->mode == DW_PCIE_RC_TYPE) + val |= DEVICE_TYPE_RC; + else if (rcar->mode == DW_PCIE_EP_TYPE) + val |= DEVICE_TYPE_EP; + else + return -EINVAL; + + if (dw->num_lanes < 4) + val |= BIFUR_MOD_SET_ON; + + writel(val, rcar->base + PCIEMSR0); + + return reset_control_deassert(dw->core_rsts[DW_PCIE_PWR_RST].rstc); +} + +void rcar_gen4_pcie_common_deinit(struct rcar_gen4_pcie *rcar) +{ + struct dw_pcie *dw = &rcar->dw; + + reset_control_assert(dw->core_rsts[DW_PCIE_PWR_RST].rstc); +} + +int rcar_gen4_pcie_prepare(struct rcar_gen4_pcie *rcar) +{ + struct device *dev = rcar->dw.dev; + int err; + + pm_runtime_enable(dev); + err = pm_runtime_resume_and_get(dev); + if (err < 0) { + dev_err(dev, "Failed to resume/get Runtime PM\n"); + pm_runtime_disable(dev); + } + + return err; +} + +void rcar_gen4_pcie_unprepare(struct rcar_gen4_pcie *rcar) +{ + struct device *dev = rcar->dw.dev; + + pm_runtime_put(dev); + pm_runtime_disable(dev); +} + +int rcar_gen4_pcie_get_resources(struct rcar_gen4_pcie *rcar) +{ + /* Renesas-specific registers */ + rcar->base = devm_platform_ioremap_resource_byname(rcar->pdev, "app"); + + return PTR_ERR_OR_ZERO(rcar->base); +} + +static const struct dw_pcie_ops dw_pcie_ops = { + .start_link = rcar_gen4_pcie_start_link, + .stop_link = rcar_gen4_pcie_stop_link, + .link_up = rcar_gen4_pcie_link_up, +}; + +struct rcar_gen4_pcie *rcar_gen4_pcie_devm_alloc(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct rcar_gen4_pcie *rcar; + + rcar = devm_kzalloc(dev, sizeof(*rcar), GFP_KERNEL); + if (!rcar) + return ERR_PTR(-ENOMEM); + + rcar->dw.ops = &dw_pcie_ops; + rcar->dw.dev = dev; + rcar->pdev = pdev; + dw_pcie_cap_set(&rcar->dw, EDMA_UNROLL); + dw_pcie_cap_set(&rcar->dw, REQ_RES); + platform_set_drvdata(pdev, rcar); + + return rcar; +} diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.h b/drivers/pci/controller/dwc/pcie-rcar-gen4.h new file mode 100644 index 000000000000..7cbb3767c2d4 --- /dev/null +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.h @@ -0,0 +1,44 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * PCIe host/endpoint controller driver for Renesas R-Car Gen4 Series SoCs + * Copyright (C) 2022-2023 Renesas Electronics Corporation + */ + +#ifndef _PCIE_RCAR_GEN4_H_ +#define _PCIE_RCAR_GEN4_H_ + +#include <linux/io.h> +#include <linux/pci.h> + +#include "pcie-designware.h" + +/* Renesas-specific */ +#define PCIEMSR0 0x0000 +#define BIFUR_MOD_SET_ON BIT(0) +#define DEVICE_TYPE_EP 0 +#define DEVICE_TYPE_RC BIT(4) + +#define PCIEINTSTS0 0x0084 +#define PCIEINTSTS0EN 0x0310 +#define MSI_CTRL_INT BIT(26) +#define SMLH_LINK_UP BIT(7) +#define RDLH_LINK_UP BIT(6) +#define PCIEDMAINTSTSEN 0x0314 +#define PCIEDMAINTSTSEN_INIT GENMASK(15, 0) + +struct rcar_gen4_pcie { + struct dw_pcie dw; + void __iomem *base; + struct platform_device *pdev; + enum dw_pcie_device_mode mode; +}; +#define to_rcar_gen4_pcie(_dw) container_of(_dw, struct rcar_gen4_pcie, dw) + +int rcar_gen4_pcie_common_init(struct rcar_gen4_pcie *rcar); +void rcar_gen4_pcie_common_deinit(struct rcar_gen4_pcie *rcar); +int rcar_gen4_pcie_prepare(struct rcar_gen4_pcie *rcar); +void rcar_gen4_pcie_unprepare(struct rcar_gen4_pcie *rcar); +int rcar_gen4_pcie_get_resources(struct rcar_gen4_pcie *rcar); +struct rcar_gen4_pcie *rcar_gen4_pcie_devm_alloc(struct platform_device *pdev); + +#endif /* _PCIE_RCAR_GEN4_H_ */
Add R-Car Gen4 PCIe Host support. This controller is based on Synopsys DesignWare PCIe, but this controller has vendor-specific registers so that requires initialization code like mode setting and retraining and so on. To reduce code delta, adds some helper functions which are used by both the host driver and the endpoint driver (which is added immediately afterwards) into a separate file. Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> --- drivers/pci/controller/dwc/Kconfig | 10 + drivers/pci/controller/dwc/Makefile | 2 + .../controller/dwc/pcie-rcar-gen4-host-drv.c | 145 ++++++++++++ drivers/pci/controller/dwc/pcie-rcar-gen4.c | 208 ++++++++++++++++++ drivers/pci/controller/dwc/pcie-rcar-gen4.h | 44 ++++ 5 files changed, 409 insertions(+) create mode 100644 drivers/pci/controller/dwc/pcie-rcar-gen4-host-drv.c create mode 100644 drivers/pci/controller/dwc/pcie-rcar-gen4.c create mode 100644 drivers/pci/controller/dwc/pcie-rcar-gen4.h