Hi Bjorn, Thank you for your review! > From: Bjorn Helgaas, Sent: Tuesday, June 14, 2022 5:34 AM > > On Mon, Jun 13, 2022 at 08:57:08PM +0900, Yoshihiro Shimoda wrote: > > Add R-Car Gen4 PCIe Host support. This controller is based on > > Synopsys Designware PCIe. > > You used "DesignWare" below, which I think is what Synopsys uses. Yes. So, I'll rename "Designware" with "DesignWare" in this description. > > Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx> > > --- > > drivers/pci/controller/dwc/Kconfig | 9 + > > drivers/pci/controller/dwc/Makefile | 1 + > > .../pci/controller/dwc/pcie-rcar-gen4-host.c | 235 ++++++++++++++++++ > > drivers/pci/controller/dwc/pcie-rcar-gen4.c | 198 +++++++++++++++ > > drivers/pci/controller/dwc/pcie-rcar-gen4.h | 59 +++++ > > 5 files changed, 502 insertions(+) > > create mode 100644 drivers/pci/controller/dwc/pcie-rcar-gen4-host.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 62ce3abf0f19..3ddccc9c38c5 100644 > > --- a/drivers/pci/controller/dwc/Kconfig > > +++ b/drivers/pci/controller/dwc/Kconfig > > @@ -384,4 +384,13 @@ config PCIE_FU740 > > Say Y here if you want PCIe controller support for the SiFive > > FU740. > > > > +config PCIE_RCAR_GEN4 > > + bool "Renesas R-Car Gen4 PCIe Host controller" > > + depends on ARCH_RENESAS || COMPILE_TEST > > + depends on PCI_MSI_IRQ_DOMAIN > > + select PCIE_DW_HOST > > + help > > + Say Y here if you want PCIe host controller support on R-Car Gen4 SoCs. > > + This uses the DesignWare core. > > > +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4-host.c > > @@ -0,0 +1,235 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * PCIe host controller driver for Renesas R-Car Gen4 Series SoCs > > + * Copyright (C) 2022 Renesas Electronics Corporation > > + */ > > + > > +#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" > > + > > +/* ASPM L1 PM Substates */ > > +#define L1PSCAP(x) (0x01bc + (x)) > > Looks like the stuff in pcie-rcar-gen4.h. Should this go there? Yes. I'll move it. > > + /* Set Max Link Width */ > > Superfluous comment, since the function name says the same thing. I got it. I'll drop it. > > + rcar_gen4_pcie_set_max_link_width(pci, pci->num_lanes); > > > +/* Link Capabilities - Maximum Link Width */ > > +#define PCI_EXP_LNKCAP_MLW_X1 BIT(4) > > +#define PCI_EXP_LNKCAP_MLW_X2 BIT(5) > > +#define PCI_EXP_LNKCAP_MLW_X4 BIT(6) > > I think we should define these in include/uapi/linux/pci_regs.h. > Use the same style as the other #defines there, i.e., > > #define PCI_EXP_LNKCAP_MLW_X1 0x00000010 > #define PCI_EXP_LNKCAP_MLW_X2 0x00000020 > #define PCI_EXP_LNKCAP_MLW_X4 0x00000040 I got it. I'll add macros from x1 to x32. > > +/* Renesas-specific */ > > +#define PCIEMSR0 0x0000 > > +#define BIFUR_MOD_SET_ON (0x1 << 0) > > +#define DEVICE_TYPE_EP (0x0 << 2) > > +#define DEVICE_TYPE_RC (0x4 << 2) > > + > > +#define PCIEINTSTS0 0x0084 > > +#define PCIEINTSTS0EN 0x0310 > > +#define MSI_CTRL_INT BIT(26) > > +#define SMLH_LINK_UP BIT(7) > > +#define RDLH_LINK_UP BIT(6) > > Is there a reason to mix the "(0x1 << 0)" style and the "BIT(26)" > styles? No, this should be fixed. I'll use "BIT()" instead. > > +extern u32 rcar_gen4_pcie_readl(struct rcar_gen4_pcie *pcie, u32 reg); > > +extern void rcar_gen4_pcie_writel(struct rcar_gen4_pcie *pcie, u32 reg, u32 val); > > +extern void rcar_gen4_pcie_set_max_link_width(struct dw_pcie *pci, int num_lanes); > > +extern int rcar_gen4_pcie_prepare(struct rcar_gen4_pcie *pcie); > > +extern void rcar_gen4_pcie_unprepare(struct rcar_gen4_pcie *pcie); > > +extern int rcar_gen4_pcie_pm_runtime_enable(struct device *dev); > > +extern void rcar_gen4_pcie_pm_runtime_disable(struct device *dev); > > +extern int rcar_gen4_pcie_devm_clk_and_reset_get(struct rcar_gen4_pcie *pcie, > > + struct device *dev); > > +extern struct rcar_gen4_pcie *rcar_gen4_pcie_devm_alloc(struct device *dev); > > Don't bother with "extern" on function declarations; this would be the > only instance in drivers/pci/. I got it. I'll drop "extern". Best regards, Yoshihiro Shimoda