cmdline.txt and config.txt for bcm2835-rpi-zero-w.dtb

Sun Jul 26 10:28:59 EDT 2020

Hello,

  Dear all, my name is Laurentiu-Cristian Duca
and I am trying to see the boot of raspberry pi 0 W on serial console
with mainline linux kernel 5.4.5 patched with preempt_rt and using
bcm2835-rpi-zero-w.dtb.

  I neet a config.txt and cmdline.txt that allows me to have
input/output on the UART console,
because I want to develop and debug programs (RTnet) on raspberry pi 0 W.
What I have tried until now in config.txt it does not work:
kernel=zImage
device_tree=bcm2835-rpi-zero-w.dtb
enable_uart=1
cmdline.txt:
root=/dev/mmcblk0p2 rootwait console=tty1 console=ttyAMA0,115200

  I can boot with serial console the rpi 4.19.y specific kernel from
github.com/raspberrypi/linux,
  using bcm2708-rpi-zero-w.dtb,
but when I try to replace with mainline kernel 5.4.5
some problems appear (see below warning)
and my applications do not work; that's why I want to use
bcm2835-rpi-zero-w.dtb.

Thank you,
Kind regards
L-C. Duca

[    0.607985] 000: ------------[ cut here ]------------
[    0.608004] 000: WARNING: CPU: 0 PID: 1 at kernel/irq/chip.c:1013
__irq_do_set_handler+0x58/0x110
[    0.608060] 000: Modules linked in:
[    0.608069] 000: CPU: 0 PID: 1 Comm: swapper Not tainted 5.4.5-rt3 #2
[    0.608085] 000: Hardware name: BCM2835
[    0.608095] 000: Backtrace:
[    0.608101] 000: [<c010c9d0>] (dump_backtrace) from [<c010ccc0>]
(show_stack+0x20/0x24)
[    0.608139] 000:  r7:00000009 r6:00000000 r5:c0ad2e81 r4:00000000
[    0.608145] 000: [<c010cca0>] (show_stack) from [<c08229fc>]
(dump_stack+0x20/0x28)
[    0.608176] 000: [<c08229dc>] (dump_stack) from [<c011fbd4>]
(__warn+0xec/0x104)
[    0.608210] 000: [<c011fae8>] (__warn) from [<c011fc6c>]
(warn_slowpath_fmt+0x80/0xa4)
[    0.608243] 000:  r9:c01634c8 r8:c0ad2e81 r7:c0d06a88 r6:00000009
r5:000003f5 r4:00000000
[    0.608250] 000: [<c011fbf0>] (warn_slowpath_fmt) from [<c01634c8>]
(__irq_do_set_handler+0x58/0x110)
[    0.608290] 000:  r9:d96f0008 r8:00000000 r7:d9405410 r6:00000001
r5:c0403b68 r4:d9405400
[    0.608296] 000: [<c0163470>] (__irq_do_set_handler) from
[<c016369c>] (irq_set_chained_handler_and_data+0x58/0x88)
[    0.608335] 000:  r9:d96f0008 r8:00000000 r7:d96d612c r6:c0403b68
r5:d9405400 r4:c0d06a88
[    0.608341] 000: [<c0163644>] (irq_set_chained_handler_and_data)
from [<c040a9b0>] (gpiochip_add_data_with_key+0x810/0x894)
[    0.608393] 000:  r7:d96d612c r6:00000002 r5:d96f0000 r4:d96d612c
[    0.608399] 000: [<c040a1a0>] (gpiochip_add_data_with_key) from
[<c040451c>] (bcm2835_pinctrl_probe+0x320/0x414)
[    0.608433] 000:  r10:00000020 r9:d9573c00 r8:d96d612c r7:d96d3340
r6:d9573c10 r5:00000003
[    0.608442] 000:  r4:d96d6040
[    0.608446] 000: [<c04041fc>] (bcm2835_pinctrl_probe) from
[<c04bfd9c>] (platform_drv_probe+0x58/0xa4)
[    0.608495] 000:  r10:c0d82168 r9:00000000 r8:c0e3b2c4 r7:c0e3b2d8
r6:c0d4234c r5:00000000
[    0.608503] 000:  r4:d9573c10
[    0.608508] 000: [<c04bfd44>] (platform_drv_probe) from
[<c04bdd4c>] (really_probe+0x2c8/0x448)
[    0.608538] 000:  r7:c0e3b2d8 r6:c0d4234c r5:00000000 r4:d9573c10
[    0.608543] 000: [<c04bda84>] (really_probe) from [<c04be248>]
(driver_probe_device+0x19c/0x1c4)
[    0.608577] 000:  r10:c0c5c838 r9:c0d7b5a0 r8:c0c86d20 r7:c04be50c
r6:c0d4234c r5:c0d4234c
[    0.608584] 000:  r4:d9573c10
[    0.608588] 000: [<c04be0ac>] (driver_probe_device) from
[<c04be4f4>] (device_driver_attach+0x54/0x6c)
[    0.608622] 000:  r9:c0d7b5a0 r8:c0c86d20 r7:c04be50c r6:c0d4234c
r5:d9573c10 r4:00000000
[    0.608628] 000: [<c04be4a0>] (device_driver_attach) from
[<c04be634>] (__driver_attach+0x128/0x148)
[    0.608656] 000:  r7:c04be50c r6:c0d4234c r5:00000000 r4:d9573c10
[    0.608661] 000: [<c04be50c>] (__driver_attach) from [<c04bbaf4>]
(bus_for_each_dev+0x74/0xb0)
[    0.608688] 000:  r7:c04be50c r6:c0d4234c r5:c0d06a88 r4:d9573c10
[    0.608693] 000: [<c04bba80>] (bus_for_each_dev) from [<c04bd3f8>]
(driver_attach+0x28/0x30)
[    0.608721] 000:  r7:00000000 r6:c0d4a188 r5:d96d3180 r4:c0d4234c
[    0.608725] 000: [<c04bd3d0>] (driver_attach) from [<c04bce60>]
(bus_add_driver+0x18c/0x1f4)
[    0.608743] 000: [<c04bccd4>] (bus_add_driver) from [<c04bece4>]
(driver_register+0xbc/0x100)
[    0.608770] 000:  r7:00000000 r6:c0c2cd74 r5:c0d06a88 r4:c0d4234c
[    0.608775] 000: [<c04bec28>] (driver_register) from [<c04bfce4>]
(__platform_driver_register+0x40/0x54)
[    0.608800] 000:  r5:c0d06a88 r4:ffffe000
[    0.608804] 000: [<c04bfca4>] (__platform_driver_register) from
[<c0c2cd94>] (bcm2835_pinctrl_driver_init+0x20/0x28)
[    0.608848] 000: [<c0c2cd74>] (bcm2835_pinctrl_driver_init) from
[<c0103068>] (do_one_initcall+0xd4/0x258)
[    0.608877] 000: [<c0102f94>] (do_one_initcall) from [<c0c01240>]
(kernel_init_freeable+0x1b8/0x200)
[    0.608913] 000:  r9:dbfffac0 r8:c0c86d20 r7:c0d7b5a0 r6:c0c5c830
r5:00000007 r4:c0d92e80
[    0.608919] 000: [<c0c01088>] (kernel_init_freeable) from
[<c083a554>] (kernel_init+0x18/0x120)
[    0.608954] 000:  r10:00000000 r9:00000000 r8:00000000 r7:00000000
r6:00000000 r5:c083a53c
[    0.608961] 000:  r4:00000000
[    0.608965] 000: [<c083a53c>] (kernel_init) from [<c01010f0>]
(ret_from_fork+0x14/0x24)
[    0.608983] 000: Exception stack(0xd94d9fb0 to 0xd94d9ff8)
[    0.608999] 000: 9fa0:                                     00000000
00000000 00000000 00000000
[    0.609018] 000: 9fc0: 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000
[    0.609032] 000: 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
[    0.609044] 000:  r5:c083a53c r4:00000000
[    0.609049] 000: ---[ end trace 0000000000000001 ]---