Test mainline kernel on an older Qualcomm SOC (msm89xx), explore current Qualcomm mainlining kernel effort
an invention by pvorel
Updated over 2 years ago. 2 hacker ♥️. 1 follower.

Project Description

Qualcomm concentrate on supporting recent SOC, older ones aren't supported (use very old downstream kernel, e.g. 3.10).

Goal for this Hackweek

1. Boot mainline kernel to initramfs

I managed to boot mainline kernel (5.9.0-rc1 at the time) on msm89xx on my phone, but kernel crashes. Find why.

$ fastboot -c "debug ignore_loglevel earlycon" boot boot.img
[74500] Continuous splash enabled, keeping panel alive.
[74500] booting linux @ 0x80000, ramdisk @ 0x2700000 (1236022), tags/device tree @ 0x2500000
[74510] Jumping to kernel via monitor
[    0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd032]
[    0.000000] Linux version 5.9.0-rc1-00020-gabea2a011c54 (pmos@localhost) (aarch64-alpine-linux-musl-gcc (Alpine 10.2.0) 10.2.0, GNU ld (GNU Binutils) 2.35.1) #3 SMP PREEMPT Tue Oct 6 12:24:55 UTC 2020
[    0.000000] printk: debug: ignoring loglevel setting.
[    0.000000] efi: UEFI not found.
[    0.000000] [Firmware Bug]: Kernel image misaligned at boot, please fix your bootloader!
[    0.000000] cma: Reserved 32 MiB at 0x00000000de000000
[    0.000000] earlycon: msm_serial_dm0 at MMIO 0x00000000f991e000 (options '115200n8')
[    0.000000] printk: bootconsole [msm_serial_dm0] enabled
...
[    0.185155] pinctrl core: initialized pinctrl subsystem
[    0.191761] DMI not present or invalid.
[    0.196193] NET: Registered protocol family 16
[    0.200769] DMA: preallocated 4096 KiB GFP_KERNEL pool for atomic allocations
[    0.204611] DMA: preallocated 4096 KiB GFP_KERNEL|GFP_DMA pool for atomic allocations
[    0.211812] DMA: preallocated 4096 KiB GFP_KERNEL|GFP_DMA32 pool for atomic allocations
[    0.218962] audit: initializing netlink subsys (disabled)
[    0.228072] thermal_sys: Registered thermal governor 'step_wise'
[    0.228076] thermal_sys: Registered thermal governor 'power_allocator'
[    0.232293] audit: type=2000 audit(0.144:1): state=initialized audit_enabled=0 res=1
[    0.244954] cpuidle: using governor menu
[    0.253102] hw-breakpoint: found 6 breakpoint and 4 watchpoint registers.
[    0.256526] ASID allocator initialised with 32768 entries
[    0.264698] Serial: AMBA PL011 UART driver
... RESET AND DOWNSTREAM KERNEL continues :(
D -     15524 - pm_driver_init, Delta

2. Explore current Qualcomm mainlining kernel effort

Resources

Results

Looking for hackers with the skills:

kernel embedded arm64 mainlining boot soc qualcomm linux

This project is part of:

Hack Week 20

Activity

  • over 2 years ago: pvorel added keyword "soc" to this project.
  • over 2 years ago: pvorel added keyword "qualcomm" to this project.
  • over 2 years ago: pvorel added keyword "linux" to this project.
  • over 4 years ago: pvorel added keyword "boot" to this project.
  • over 4 years ago: pvorel added keyword "mainlining" to this project.
  • over 4 years ago: pvorel added keyword "arm64" to this project.
  • over 4 years ago: iivanov liked this project.
  • over 4 years ago: cfconrad liked this project.
  • over 4 years ago: pvorel added keyword "kernel" to this project.
  • over 4 years ago: pvorel added keyword "embedded" to this project.
  • over 4 years ago: pvorel started this project.
  • over 4 years ago: pvorel originated this project.


    • Comments

    • pvorel
      over 4 years ago by pvorel | Reply

      My fix posted into linux-arm-msm ML got accepted https://lore.kernel.org/linux-arm-msm/20210415193913.1836153-1-petr.vorel@gmail.com/ https://git.kernel.org/pub/scm/linux/kernel/git/qcom/linux.git/commit/?h=for-next&id=f890f89d9a80fffbfa7ca791b78927e5b8aba869

      Unfortunately there is still issue preventing boot with commit 86588296acbf ("fdt: Properly handle "no-map" field in the memory region"). Reverting it allows booting. I need to have look into this issue.

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