Hi, @O635789
I just do the test.
I use rockpi4_debian_stretch_lxde_armhf_20181105_2120-gpt.img. And I install rockchip-overlay , rockchip-fstab and rockpi4-dtbo package. Then update the u-boot and kernel to the newest version. Reboot.
When the contents of /boot/hw_intfc.conf are
intfc:pwm0=off
intfc:pwm1=off
intfc:uart2=on
intfc:uart4=on
intfc:spi1=off
intfc:spi2=off
intfc:i2c2=off
intfc:i2c6=off
intfc:i2c7=off
#intfc:dtoverlay=at24c02
#intfc:dtoverlay=two-color-led
#intfc:dtoverlay=console-disabled
#intfc:dtoverlay=console-on-uart4
And I execute sudo dmesg, it shows the same result as yours.
[ 2.242621] Serial: 8250/16550 driver, 5 ports, IRQ sharing disabled
[ 2.245435] ff180000.serial: ttyS0 at MMIO 0xff180000 (irq = 35, base_baud = 1500000) is a 16550A
[ 2.246630] rockchip-pinctrl pinctrl: pin gpio4-19 already requested by fiq-debugger; cannot claim for ff1a0000.serial
[ 2.247599] rockchip-pinctrl pinctrl: pin-147 (ff1a0000.serial) status -22
[ 2.248208] rockchip-pinctrl pinctrl: could not request pin 147 (gpio4-19) from group uart2c-xfer on device rockchip-pinctrl
[ 2.249201] dw-apb-uart ff1a0000.serial: Error applying setting, reverse things back
[ 2.250295] ff1a0000.serial: ttyS2 at MMIO 0xff1a0000 (irq = 36, base_baud = 1500000) is a 16550A
[ 2.251923] ff370000.serial: ttyS4 at MMIO 0xff370000 (irq = 38, base_baud = 1500000) is a 16550A
When the contents are modified to
intfc:pwm0=off
intfc:pwm1=off
intfc:uart2=on
intfc:uart4=on
intfc:spi1=off
intfc:spi2=off
intfc:i2c2=off
intfc:i2c6=off
intfc:i2c7=off
#intfc:dtoverlay=at24c02
#intfc:dtoverlay=two-color-led
intfc:dtoverlay=console-disabled
#intfc:dtoverlay=console-on-uart4
It shows
[ 2.124915] pwm-regulator vdd-log: Looking up pwm-supply from device tree
[ 2.124925] pwm-regulator vdd-log: Looking up pwm-supply property in node /vdd-log failed
[ 2.125018] pwm-regulator vdd-log: Looking up pwm-supply from device tree
[ 2.125027] pwm-regulator vdd-log: Looking up pwm-supply property in node /vdd-log failed
[ 2.125390] Serial: 8250/16550 driver, 5 ports, IRQ sharing disabled
[ 2.127009] ff180000.serial: ttyS0 at MMIO 0xff180000 (irq = 35, base_baud = 1500000) is a 16550A
[ 2.127624] ff1a0000.serial: ttyS2 at MMIO 0xff1a0000 (irq = 36, base_baud = 1500000) is a 16550A
[ 2.128245] ff370000.serial: ttyS4 at MMIO 0xff370000 (irq = 38, base_baud = 1500000) is a 16550A
[ 2.129252] [drm] Initialized drm 1.1.0 20060810
[ 2.132979] [drm] Rockchip DRM driver version: v1.0.1
When uncomment intfc:dtoverlay=console-disabled, the fiq-debugger is not registered.