Bjorn Helgaas [off-list ref] 於 2021年5月4日 週二 下午9:46寫道：

On Tue, May 04, 2021 at 06:59:39PM +0800, Greentime Hu wrote:

quoted

From: Paul Walmsley <redacted>

Add driver for the SiFive FU740 PCIe host controller.
This controller is based on the DesignWare PCIe core.

Signed-off-by: Paul Walmsley <redacted>
Co-developed-by: Henry Styles <redacted>
Signed-off-by: Henry Styles <redacted>
Co-developed-by: Erik Danie <redacted>
Signed-off-by: Erik Danie <redacted>
Co-developed-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
---
 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.

   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

quoted

+     select PCIE_DW_HOST
+     help
+       Say Y here if you want PCIe controller support for the SiFive
+       FU740.
+
 endmenu

Hi,

Sorry for late to debug this case. I was working on other works and
just missed the email.
How about this?

diff --git a/arch/riscv/Kconfig.socs b/arch/riscv/Kconfig.socs
index e1b2690b6e45..66f57f2db49d 100644
--- a/arch/riscv/Kconfig.socs
+++ b/arch/riscv/Kconfig.socs

@@ -7,6 +7,7 @@ config SOC_SIFIVE
        select CLK_SIFIVE
        select CLK_SIFIVE_PRCI
        select SIFIVE_PLIC
+       select GPIOLIB if PCIE_FU740
        help
          This enables support for SiFive SoC platform hardware.

diff --git a/drivers/pci/controller/dwc/Kconfig

b/drivers/pci/controller/dwc/Kconfig
index 255d43b1661b..0a37d21ed64e 100644

--- a/drivers/pci/controller/dwc/Kconfig
+++ b/drivers/pci/controller/dwc/Kconfig

@@ -322,7 +322,6 @@ config PCIE_FU740
        bool "SiFive FU740 PCIe host controller"
        depends on PCI_MSI_IRQ_DOMAIN
        depends on SOC_SIFIVE || COMPILE_TEST
-       depends on GPIOLIB
        select PCIE_DW_HOST
        help
          Say Y here if you want PCIe controller support for the SiFive