Unable to Load PHY Drivers Automatically for ARM SoCs

[NN708]

ARM SoCs require PHY drivers for proper functionality of USB and PCIe interfaces. Currently, these drivers do not load automatically even with modules: phy_rockchip_inno_usb2,phy_rockchip_snps_pcie3. It only works with modules_force_load: phy_rockchip_inno_usb2,phy_rockchip_snps_pcie3. I hope the PHY drivers could load automatically with the default configuration.

Booster version: 0.12 OS: Alpine Linux edge

Related issue: alpine/mkinitfs#76

[anatol]

Thank you for the report.

I tried to grep linux sources for phy_rockchip_inno_usb2 but there is nothing there. But I assume it is this driver https://github.com/torvalds/linux/blob/master/drivers/phy/rockchip/phy-rockchip-inno-usb2.c

Hows does ARM load the drivers? Is it still udev events? Does your system send a udev event specific for the hardware you mentioned?

[NN708]

I tried to grep linux sources for phy_rockchip_inno_usb2 but there is nothing there. But I assume it is this driver https://github.com/torvalds/linux/blob/master/drivers/phy/rockchip/phy-rockchip-inno-usb2.c

Yes, that's the driver needed.

Hows does ARM load the drivers? Is it still udev events? Does your system send a udev event specific for the hardware you mentioned?

Here are the debug messages related to USB when PHY drivers are force-loaded:

udev event {Action:add KObj:/devices/platform/fe8a0000.usb2phy/extcon/extcon0 Env: map[ACTION:add DEVPATH:/devices/platform/fe8a0000.usb2phy/extcon/extcon0 SEQNUM:1088 SUBSYSTEM:extcon]}
udev event {Action:add KObj:/devices/virtual/devlink/regulator:regulator.6--phy:phy-fe8a0000.usb2phy.4 Env:map[ACTION:add DEVPATH:/devices/virtual/devlink/regulator:regulator.6--phy:phy-fe8a0000.usb2phy.4 SEQNUM:1091 SUBSYSTEM:devlink]}
udev event {Action:add KObj:/devices/platform/fe8a0000.usb2phy/phy/phy-fe8a0000.usb2phy.4 Env:map[ACTION:add DEVPATH:/devices/platform/fe8a0000.usb2phy/phy/phy-fe8a0000.usb2phy.4 OF_COMPATIBLE_N:0 OF_FULLNAME:/usb2phy@fe8a0000/host-port OF_NAME:host-port SEQNUM:1093 SUBSYSTEM:phy]}
udev event {Action:add KObj:/devices/platform/fe8a0000.usb2phy/phy/phy-fe8a0000.usb2phy.5 Env:map[ACTION:add DEVPATH:/devices/platform/fe8a0000.usb2phy/phy/phy-fe8a0000.usb2phy.5 OF_COMPATIBLE_N:0 OF_FULLNAME:/usb2phy@fe8a0000/otg-port OF_NAME:otg-port SEQNUM:1095 SUBSYSTEM:phy]}
udev event {Action:add KObj:/devices/virtual/devlink/platform:fe8a0000.usb2phy--platform:fd000000.usb Env:map[ACTION:add DEVPATH:/devices/virtual/devlink/platform:fe8a0000.usb2phy--platform:fd000000.usb SEQNUM:1098 SUBSYSTEM:devlink]}
udev event {Action:remove KObj:/devices/virtual/devlink/platform:vcc5v0-usb-host-regulator--platform:fe8a0000.usb2phy Env:map[ACTION:remove DEVPATH:/devices/virtual/devlink/platform:vcc5v0-usb-host-regulator--platform:fe8a0000.usb2phy SEQNUM:1099 SUBSYSTEM:devlink]}
udev event {Action:bind KObj:/devices/platform/fe8a0000.usb2phy Env:map[ACTION:bind DEVPATH:/devices/platform/fe8a0000.usb2phy DRIVER:rockchip-usb2phy MODALIAS:of: Nusb2phyT(null)Crockchip,rk3568-usb2phy OF_COMPATIBLE_0:rockchip,rk3568-usb2phy OF_COMPATIBLE_N:1 OF_FULLNAME:/usb2phy@fe8a0000 OF_NAME:usb2phy SEQNUM:1100 SUBSYSTEM:platform]}
modalias of:Nusb2phyT(null)Crockchip,rk3568_usb2phy matched module phy_rockchip_inno_usb2

When the drivers are not force-loaded, the output is as follows:

modalias of:Nusb2phyT(null)Crockchip,rk3568-usb2phy matched module uio_pdrv_genirq