Hi Bjorn, On Wed, 24 Mar 2021 at 04:30, Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote: > > On Mon, Mar 22, 2021 at 05:18:31PM +0800, Chunyan Zhang wrote: > > From: Hongtao Wu <billows.wu@xxxxxxxxxx> > > > > This series adds PCIe controller driver for Unisoc SoCs. > > This controller is based on DesignWare PCIe IP. > > > > Signed-off-by: Hongtao Wu <billows.wu@xxxxxxxxxx> > > Signed-off-by: Chunyan Zhang <zhang.lyra@xxxxxxxxx> > > --- > > drivers/pci/controller/dwc/Kconfig | 12 + > > drivers/pci/controller/dwc/Makefile | 1 + > > drivers/pci/controller/dwc/pcie-sprd.c | 292 +++++++++++++++++++++++++ > > 3 files changed, 305 insertions(+) > > create mode 100644 drivers/pci/controller/dwc/pcie-sprd.c > > > > diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig > > index 22c5529e9a65..61f0b79f963d 100644 > > --- a/drivers/pci/controller/dwc/Kconfig > > +++ b/drivers/pci/controller/dwc/Kconfig > > @@ -318,4 +318,16 @@ 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_SPRD > > Maybe you want PCIE_SPRD_HOST for this one so there's room for a > PCIE_SPRD_EP someday? yes, it makes sense, will address. > > > + tristate "Unisoc PCIe controller - Host Mode" > > + depends on ARCH_SPRD || COMPILE_TEST > > + depends on PCI_MSI_IRQ_DOMAIN > > + select PCIE_DW_HOST > > + help > > + Unisoc PCIe controller uses the DesignWare core. It can be configured > > + as an Endpoint (EP) or a Root complex (RC). In order to enable host > > + mode (the controller works as RC), PCIE_SPRD must be selected. > > + Say Y or M here if you want to PCIe RC controller support on Unisoc > > + SoCs. > > + > > endmenu > > diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile > > index a751553fa0db..eb546e97c14a 100644 > > --- a/drivers/pci/controller/dwc/Makefile > > +++ b/drivers/pci/controller/dwc/Makefile > > @@ -20,6 +20,7 @@ obj-$(CONFIG_PCI_MESON) += pci-meson.o > > obj-$(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_SPRD) += pcie-sprd.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-sprd.c b/drivers/pci/controller/dwc/pcie-sprd.c > > new file mode 100644 > > index 000000000000..2ccb99eda24f > > --- /dev/null > > +++ b/drivers/pci/controller/dwc/pcie-sprd.c > > @@ -0,0 +1,292 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * PCIe host controller driver for Unisoc SoCs > > + * > > + * Copyright (C) 2020-2021 Unisoc, Inc. > > + * > > + * Author: Hongtao Wu <Billows.Wu@xxxxxxxxxx> > > + */ > > + > > +#include <linux/delay.h> > > +#include <linux/gpio/consumer.h> > > +#include <linux/interrupt.h> > > +#include <linux/mfd/syscon.h> > > +#include <linux/module.h> > > +#include <linux/of_device.h> > > +#include <linux/of_irq.h> > > +#include <linux/platform_device.h> > > +#include <linux/property.h> > > +#include <linux/regmap.h> > > + > > +#include "pcie-designware.h" > > + > > +/* aon apb syscon */ > > +#define IPA_ACCESS_CFG 0xcd8 > > +#define AON_ACCESS_PCIE_EN BIT(1) > > + > > +/* pmu apb syscon */ > > +#define SNPS_PCIE3_SLP_CTRL 0xac > > +#define PERST_N_ASSERT BIT(1) > > +#define PERST_N_AUTO_EN BIT(0) > > +#define PD_PCIE_CFG_0 0x3e8 > > +#define PCIE_FORCE_SHUTDOWN BIT(25) > > + > > +#define PCIE_SS_REG_BASE 0xE00 > > Pick uppercase or lowercase for your hex constants and use it > consistently. > > > +#define APB_CLKFREQ_TIMEOUT 0x4 > > +#define BUSERR_EN BIT(12) > > +#define APB_TIMER_DIS BIT(10) > > +#define APB_TIMER_LIMIT GENMASK(31, 16) > > + > > +#define PE0_GEN_CTRL_3 0x58 > > +#define LTSSM_EN BIT(0) > > + > > +struct sprd_pcie_soc_data { > > + u32 syscon_offset; > > +}; > > + > > +static const struct sprd_pcie_soc_data ums9520_syscon_data = { > > + .syscon_offset = 0x1000, /* The offset of set/clear register */ > > +}; > > + > > +struct sprd_pcie { > > + u32 syscon_offset; > > + struct device *dev; > > + struct dw_pcie *pci; > > + struct regmap *aon_map; > > + struct regmap *pmu_map; > > + const struct sprd_pcie_soc_data *socdata; > > +}; > > + > > +enum sprd_pcie_syscon_type { > > + normal_syscon, /* it's not a set/clear register */ > > + set_syscon, /* set a set/clear register */ > > + clr_syscon, /* clear a set/clear register */ > > +}; > > + > > +static void sprd_pcie_buserr_enable(struct dw_pcie *pci) > > +{ > > + u32 val; > > + > > + val = dw_pcie_readl_dbi(pci, PCIE_SS_REG_BASE + APB_CLKFREQ_TIMEOUT); > > + val &= ~APB_TIMER_DIS; > > + val |= BUSERR_EN; > > + val |= APB_TIMER_LIMIT & (0x1f4 << 16); > > + dw_pcie_writel_dbi(pci, PCIE_SS_REG_BASE + APB_CLKFREQ_TIMEOUT, val); > > +} > > + > > +static void sprd_pcie_ltssm_enable(struct dw_pcie *pci, bool enable) > > +{ > > + u32 val; > > + > > + val = dw_pcie_readl_dbi(pci, PCIE_SS_REG_BASE + PE0_GEN_CTRL_3); > > + if (enable) > > + dw_pcie_writel_dbi(pci, PCIE_SS_REG_BASE + PE0_GEN_CTRL_3, > > + val | LTSSM_EN); > > + else > > + dw_pcie_writel_dbi(pci, PCIE_SS_REG_BASE + PE0_GEN_CTRL_3, > > + val & ~LTSSM_EN); > > +} > > + > > +static int sprd_pcie_syscon_set(struct sprd_pcie *ctrl, struct regmap *map, > > + u32 reg, u32 mask, u32 val, > > + enum sprd_pcie_syscon_type type) > > +{ > > + int ret = 0; > > + u32 read_val; > > + u32 offset = ctrl->syscon_offset; > > + struct device *dev = ctrl->pci->dev; > > + > > + /* > > + * Each set/clear register has three registers: > > + * reg: base register > > + * reg + offset: set register > > + * reg + offset * 2: clear register > > + */ > > + switch (type) { > > + case normal_syscon: > > + ret = regmap_read(map, reg, &read_val); > > + if (ret) { > > + dev_err(dev, "failed to read register 0x%x\n", reg); > > + return ret; > > + } > > + read_val &= ~mask; > > + read_val |= (val & mask); > > + ret = regmap_write(map, reg, read_val); > > + break; > > + case set_syscon: > > + reg = reg + offset; > > + ret = regmap_write(map, reg, val); > > + break; > > + case clr_syscon: > > + reg = reg + offset * 2; > > + ret = regmap_write(map, reg, val); > > + break; > > + default: > > + break; > > Unnecessary default case. I can remove this, but I have been thinking that we should leave a default case even if it does nothing to make the switch-case complete. > > > + } > > + > > + if (ret) > > + dev_err(dev, "failed to write register 0x%x\n", reg); > > + > > + return ret; > > +} > > + > > +static int sprd_pcie_perst_assert(struct sprd_pcie *ctrl) > > +{ > > + return sprd_pcie_syscon_set(ctrl, ctrl->pmu_map, SNPS_PCIE3_SLP_CTRL, > > + PERST_N_ASSERT, PERST_N_ASSERT, set_syscon); > > +} > > + > > +static int sprd_pcie_perst_deassert(struct sprd_pcie *ctrl) > > +{ > > + int ret; > > + > > + ret = sprd_pcie_syscon_set(ctrl, ctrl->pmu_map, SNPS_PCIE3_SLP_CTRL, > > + PERST_N_ASSERT, 0, clr_syscon); > > + usleep_range(2000, 3000); > > It'd be nice to have a spec reference for this delay. Ok. > > > + return ret; > > +} > > + > > +static int sprd_pcie_power_on(struct platform_device *pdev) > > You could pass in the "struct sprd_pcie *" here since the caller has > that already. Ok. > > > +{ > > + int ret; > > + struct sprd_pcie *ctrl = platform_get_drvdata(pdev); > > + struct dw_pcie *pci = ctrl->pci; > > + > > + ret = sprd_pcie_syscon_set(ctrl, ctrl->aon_map, PD_PCIE_CFG_0, > > + PCIE_FORCE_SHUTDOWN, 0, clr_syscon); > > + if (ret) > > + return ret; > > + > > + ret = sprd_pcie_syscon_set(ctrl, ctrl->aon_map, IPA_ACCESS_CFG, > > + AON_ACCESS_PCIE_EN, AON_ACCESS_PCIE_EN, > > + set_syscon); > > + if (ret) > > + return ret; > > + > > + ret = sprd_pcie_perst_deassert(ctrl); > > + if (ret) > > + return ret; > > + > > + sprd_pcie_buserr_enable(pci); > > + sprd_pcie_ltssm_enable(pci, true); > > + > > + return ret; > > +} > > + > > +static int sprd_pcie_power_off(struct platform_device *pdev) > > And here. Caller would have to look up platform_get_drvdata(), as is > done in other drivers. > > > +{ > > + struct sprd_pcie *ctrl = platform_get_drvdata(pdev); > > + struct dw_pcie *pci = ctrl->pci; > > + > > + sprd_pcie_ltssm_enable(pci, false); > > + > > + sprd_pcie_perst_assert(ctrl); > > + sprd_pcie_syscon_set(ctrl, ctrl->aon_map, PD_PCIE_CFG_0, > > + PCIE_FORCE_SHUTDOWN, PCIE_FORCE_SHUTDOWN, > > + set_syscon); > > + sprd_pcie_syscon_set(ctrl, ctrl->aon_map, IPA_ACCESS_CFG, > > + AON_ACCESS_PCIE_EN, 0, clr_syscon); > > + > > + return 0; > > +} > > + > > +static int sprd_add_pcie_port(struct platform_device *pdev) > > And here. Look at the other drivers in drivers/pci/controller/dwc/ > and make yours as much like them as possible. This is not the place > for innovation. Ok, will do. > > > +{ > > + struct sprd_pcie *ctrl = platform_get_drvdata(pdev); > > + struct dw_pcie *pci = ctrl->pci; > > + struct pcie_port *pp = &pci->pp; > > + > > + return dw_pcie_host_init(pp); > > +} > > + > > +static int sprd_pcie_probe(struct platform_device *pdev) > > +{ > > + struct device *dev = &pdev->dev; > > + struct sprd_pcie *ctrl; > > + struct dw_pcie *pci; > > + int ret; > > + > > + ctrl = devm_kzalloc(dev, sizeof(*ctrl), GFP_KERNEL); > > + if (!ctrl) > > + return -ENOMEM; > > + > > + ctrl->socdata = > > + (struct sprd_pcie_soc_data *)of_device_get_match_data(dev); > > Unnecessary cast. > > It doesn't look like you even need to save this pointer in the struct > sprd_pcie. You use it below to get syscon_offset, but never reference > it after this function. > > > + if (!ctrl->socdata) { > > + dev_warn(dev, > > + "using the default set/clear register offset address"); > > + ctrl->syscon_offset = 0x1000; > > + } > > + ctrl->syscon_offset = ctrl->socdata->syscon_offset; > > + > > + ctrl->aon_map = syscon_regmap_lookup_by_phandle(dev->of_node, > > + "sprd, regmap-aon"); > > + if (IS_ERR(ctrl->aon_map)) { > > + dev_err(dev, "failed to get syscon regmap aon\n"); > > I think it's worth mentioning the exact string ("sprd, regmap-aon") > you were looking for. Also below. > > > + ret = PTR_ERR(ctrl->aon_map); > > + goto err; > > + } > > + > > + ctrl->pmu_map = syscon_regmap_lookup_by_phandle(dev->of_node, > > + "sprd, regmap-pmu"); > > + if (IS_ERR(ctrl->pmu_map)) { > > + dev_err(dev, "failed to get syscon regmap pmu\n"); > > + ret = PTR_ERR(ctrl->pmu_map); > > + goto err; > > + } > > + > > + pci = ctrl->pci; > > + pci->dev = dev; > > + > > + platform_set_drvdata(pdev, ctrl); > > + > > + ret = sprd_pcie_power_on(pdev); > > + if (ret < 0) { > > + dev_err(dev, "failed to power on, return %d\n", > > + ret); > > + goto err_power_off; > > + } > > + > > + ret = sprd_add_pcie_port(pdev); > > + if (ret) { > > + dev_warn(dev, "failed to initialize RC controller\n"); > > + return ret; > > You power off for the previous error but not this one? Yes, I will fix this. Thanks for your review! Chunyan > > > + } > > + > > + return 0; > > + > > +err_power_off: > > + sprd_pcie_power_off(pdev); > > +err: > > + return ret; > > +} > > + > > +static int sprd_pcie_remove(struct platform_device *pdev) > > +{ > > + sprd_pcie_power_off(pdev); > > + > > + return 0; > > +} > > + > > +static const struct of_device_id sprd_pcie_of_match[] = { > > + { > > + .compatible = "sprd,ums9520-pcie", > > + .data = &ums9520_syscon_data, > > + }, > > + {}, > > +}; > > + > > +static struct platform_driver sprd_pcie_driver = { > > + .probe = sprd_pcie_probe, > > + .remove = sprd_pcie_remove, > > + .driver = { > > + .name = "sprd-pcie", > > + .of_match_table = sprd_pcie_of_match, > > + }, > > +}; > > +module_platform_driver(sprd_pcie_driver); > > + > > +MODULE_DESCRIPTION("Unisoc PCIe host controller driver"); > > +MODULE_LICENSE("GPL"); > > -- > > 2.25.1 > >