On Tue, May 04, 2021 at 08:46:32AM -0500, Bjorn Helgaas wrote: > On Tue, May 04, 2021 at 06:59:39PM +0800, 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 | 10 + > > drivers/pci/controller/dwc/Makefile | 1 + > > drivers/pci/controller/dwc/pcie-fu740.c | 309 ++++++++++++++++++++++++ > > 3 files changed, 320 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..255d43b1661b 100644 > > --- a/drivers/pci/controller/dwc/Kconfig > > +++ b/drivers/pci/controller/dwc/Kconfig > > @@ -318,4 +318,14 @@ 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 > > + depends on GPIOLIB > > 1) I'm a little disappointed that I reported the build issue 6 days > ago when we were already in the merge window, and it's taken until > now to make some progress. > > 2) I would prefer not to depend on GPIOLIB because it reduces > compile-test coverage. For example, the x86_64 defconfig does not > enable GPIOLIB, so one must manually enable it to even be able to > enable PCIE_FU740. > > Many other PCI controller drivers use GPIO, but no others depend on > GPIOLIB, so I infer that in the !GPIOLIB case, gpio/consumer.h > provides the stubs required for compile testing. > > We could have a conversation about whether it's better to > explicitly depend on GPIOLIB here, or whether building a working > FU740 driver implicitly depends on GPIOLIB being selected > elsewhere. That implicit dependency *is* a little obscure, but I > think that's what other drivers currently do, and I'd like to do > this consistently unless there's a good reason otherwise. I will drop the explicit GPIOLIB dependency and push it out. For (1) I agree with you - I merged when I received some input - it is reasonable to avoid adding it to v5.13 material for this reason, apologies. Thanks, Lorenzo > Here are some examples of other drivers: > > dwc/pci-dra7xx.c: > config PCI_DRA7XX_HOST > depends on SOC_DRA7XX || COMPILE_TEST > > config SOC_DRA7XX > select ARCH_OMAP2PLUS > > config ARCH_OMAP2PLUS > select GPIOLIB > > dwc/pci-meson.c: > config PCI_MESON > # doesn't, but probably *should* depend on "ARCH_MESON || COMPILE_TEST" > > menuconfig ARCH_MESON > select GPIOLIB > > dwc/pcie-qcom.c: > config PCIE_QCOM > depends on OF && (ARCH_QCOM || COMPILE_TEST) > > config ARCH_QCOM > select GPIOLIB > > pcie-rockchip.c: > config PCIE_ROCKCHIP_HOST > depends on ARCH_ROCKCHIP || COMPILE_TEST > > config ARCH_ROCKCHIP > select GPIOLIB > > > + select PCIE_DW_HOST > > + help > > + Say Y here if you want PCIe controller support for the SiFive > > + FU740. > > + > > endmenu