Re: [PATCH v3 4/5] phy: Add ARTPEC-8 PCIe PHY driver

[Vinod Koul <vkoul@kernel.org>]

On 06-07-22, 17:10, Wangseok Lee wrote:
> On 05-07-22, 15:30, Vinod Koul wrote:
> > On 14-06-22, 10:34, Wangseok Lee wrote:
> >> Add support Axis, ARTPEC-8 SoC.
> >> ARTPEC-8 is the SoC platform of Axis Communications.
> >> This is based on arm64 and support GEN4 & 2lane.
> >> This driver provides PHY interface for ARTPEC-8 SoC PCIe controller,
> >> based on Samsung PCIe PHY IP.
> >> 
> >> Signed-off-by: Wangseok Lee <wangseok.lee@samsung.com>
> >> Signed-off-by: Jaeho Cho <jaeho79.cho@samsung.com>
> >> ---
> >> v2->v3 :
> >> -remove unnecessary indentation
> >> -redefine local struct to statis const
> >> -add static const to struct that requires static const definition
> >> -remove wrappers on writel and readl
> >> 
> >> v1->v2 :
> >> -change folder name of phy driver to axis from artpec
> >> ---
> >>  drivers/phy/Kconfig                 |   1 +
> >>  drivers/phy/Makefile                |   1 +
> >>  drivers/phy/axis/Kconfig            |   9 +
> >>  drivers/phy/axis/Makefile           |   2 +
> >>  drivers/phy/axis/phy-artpec8-pcie.c | 776 ++++++++++++++++++++++++++++++++++++
> >>  5 files changed, 789 insertions(+)
> >>  create mode 100644 drivers/phy/axis/Kconfig
> >>  create mode 100644 drivers/phy/axis/Makefile
> >>  create mode 100644 drivers/phy/axis/phy-artpec8-pcie.c
> >> 
> >> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> >> index 300b0f2..92b8232 100644
> >> --- a/drivers/phy/Kconfig
> >> +++ b/drivers/phy/Kconfig
> >> @@ -73,6 +73,7 @@ config PHY_CAN_TRANSCEIVER
> >>  
> >>  source "drivers/phy/allwinner/Kconfig"
> >>  source "drivers/phy/amlogic/Kconfig"
> >> +source "drivers/phy/axis/Kconfig"
> >>  source "drivers/phy/broadcom/Kconfig"
> >>  source "drivers/phy/cadence/Kconfig"
> >>  source "drivers/phy/freescale/Kconfig"
> >> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> >> index 01e9eff..808c055e 100644
> >> --- a/drivers/phy/Makefile
> >> +++ b/drivers/phy/Makefile
> >> @@ -12,6 +12,7 @@ obj-$(CONFIG_PHY_PISTACHIO_USB)                += phy-pistachio-usb.o
> >>  obj-$(CONFIG_USB_LGM_PHY)                += phy-lgm-usb.o
> >>  obj-y                                        += allwinner/        \
> >>                                             amlogic/        \
> >> +                                           axis/                \
> >>                                             broadcom/        \
> >>                                             cadence/        \
> >>                                             freescale/        \
> >> diff --git a/drivers/phy/axis/Kconfig b/drivers/phy/axis/Kconfig
> >> new file mode 100644
> >> index 0000000..7198b93
> >> --- /dev/null
> >> +++ b/drivers/phy/axis/Kconfig
> >> @@ -0,0 +1,9 @@
> >> +config PHY_ARTPEC8_PCIE
> >> +        bool "ARTPEC-8 PCIe PHY driver"
> >> +        depends on OF && (ARCH_ARTPEC8 || COMPILE_TEST)
> >> +        select GENERIC_PHY
> >> +        help
> >> +          Enable PCIe PHY support for ARTPEC-8 SoC.
> >> +          This driver provides PHY interface for ARTPEC-8 SoC
> >> +          PCIe controller.
> >> +          This is based on Samsung PCIe PHY IP.
> > 
> > How different is it from SS IP and why should it not be under
> > phy/samsung/ then?
> > 
> 
> SoC platform is completely different from exynos platform and different 
> from exynos PCIe PHY. So the overall sysreg configuration is different
> and register map is also different. The reset method and type of PHY for
> initialization are different. This is not a driver that supports Samsung
> SoC platform, but this PHY driver that supports only Axis, Artpec-8
> platforms, so it is not added to phy/samsung.

SoC is a moot point. If the IP block is same then we should try to reuse
the existing phy driver, modifications to current driver to support your
changes should be fine...

Is that feasible?

-- 
~Vinod