[U-Boot] arm: mvebu: u-boot does not start on db-88f6820-gp

[Stefan Eichenberger]

Hi Stefan,

On 09/04/2015 06:44 PM, Stefan Roese wrote:

>> Unfortunately u-boot now hangs if I try to load an image from the 
>> SD-Card:
>> e.g. if I run the following command u-boot hangs:
>> ext4load mmc 0:2 0x2000000 /boot/kernel.bin
>>
>> I don't see why exactly it crashes, it seems for me that it's always at
>> a different position.
>>
>> Here are two backtraces, always at a different positions:
>>
>> Here u-boot stopped automatically:
>> Program received signal SIGTRAP, Trace/breakpoint trap.
>> 0x7ff65d84 in ?? ()
>> (gdb) backtrace
>> #0  0x7ff65d84 in ?? ()
>> #1  0x803663d0 in ?? ()
>> #2  0x803663d0 in ?? ()
>> Backtrace stopped: previous frame identical to this frame (corrupt 
>> stack?)
>>
>> And here I've got perhaps some more information?
>> Program received signal SIGSTOP, Stopped (signal).
>> v7_inval_dcache_level_setway (log2_line_len=<optimized out>,
>> way_shift=<optimized out>, num_ways=<optimized out>,
>>      num_sets=<optimized out>, level=<optimized out>) at
>> arch/arm/cpu/armv7/cache_v7.c:62
>> 62                      for (set = num_sets - 1; set >= 0; set--) {
>> (gdb) backtrace
>> #0  v7_inval_dcache_level_setway (log2_line_len=<optimized out>,
>> way_shift=<optimized out>,
>>      num_ways=<optimized out>, num_sets=<optimized out>,
>> level=<optimized out>) at arch/arm/cpu/armv7/cache_v7.c:62
>> #1  v7_maint_dcache_level_setway (operation=<optimized out>, level=9) at
>> arch/arm/cpu/armv7/cache_v7.c:129
>> #2  v7_maint_dcache_all (operation=2146852864) at
>> arch/arm/cpu/armv7/cache_v7.c:147
>> #3  0xfffffbe2 in ?? ()
>> #4  0xfffffbe2 in ?? ()
>>
>> Could it be that there is something wrong with cache/dram setup?
>
> Maybe. Hard to tell. Why don't you use "dcache off" before you start 
> the command. If this works, then we still have a problem with cache 
> (L1 / L2)...

I now did some tests, it seems that the kernel only crashes if I access 
the SD-Card, I'm able to load the kernel from an USB-Device. I tried to 
disable the dcache but the problem still remains.

Another problem I have is that if I try to start a mainline kernel, it 
will crash with the following trace, I think it doesn't find the 
devicetree for some reasons:
## Booting kernel from Legacy Image at 02000000 ...
    Image Name:
    Image Type:   ARM Linux Kernel Image (uncompressed)
    Data Size:    7258976 Bytes = 6.9 MiB
    Load Address: 00008000
    Entry Point:  00008000
    Verifying Checksum ... OK
## Flattened Device Tree blob at 03000000
    Booting using the fdt blob at 0x3000000
    Loading Kernel Image ... OK
    Loading Device Tree to 7fb49000, end 7fb4ee70 ... OK

Starting kernel ...

[    0.000000] Booting Linux on physical CPU 0x0
[    0.000000] Linux version 4.2.0 (eichenberger at gruene) (gcc version 
4.6.4 (Marvell GCC release 20150204-c4af733b 645
[    0.000000] CPU: ARMv7 Processor [414fc091] revision 1 (ARMv7), 
cr=10c5387d
[    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing 
instruction cache
[    0.000000] Machine model: Marvell Armada 385 Development Board
[    0.000000] bootconsole [earlycon0] enabled
[    0.000000] Memory policy: Data cache writealloc
[    0.000000] Unable to handle kernel paging request at virtual address 
3fb49000
[    0.000000] pgd = c0004000
[    0.000000] [3fb49000] *pgd=00000000
[    0.000000] Internal error: Oops: 5 [#1] SMP ARM
[    0.000000] Modules linked in:
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.2.0 #67
[    0.000000] Hardware name: Marvell Armada 380/385 (Device Tree)
[    0.000000] task: c06bd528 ti: c06b8000 task.ti: c06b8000
[    0.000000] PC is at fdt_check_header+0x0/0x78
[    0.000000] LR is at __unflatten_device_tree+0x1c/0x12c
[    0.000000] pc : [<c04d960c>]    lr : [<c039419c>] psr: 200001d3
[    0.000000] sp : c06b9f38  ip : 00000000  fp : ef7fce40
[    0.000000] r10: c071d2f0  r9 : c05c4d7c  r8 : 3fb49000
[    0.000000] r7 : c069454c  r6 : c06be514  r5 : c0712f68  r4 : c069454c
[    0.000000] r3 : c071d308  r2 : c069454c  r1 : c071d2f0  r0 : 3fb49000
[    0.000000] Flags: nzCv  IRQs off  FIQs off  Mode SVC_32  ISA ARM  
Segment kernel
[    0.000000] Control: 10c5387d  Table: 0000404a  DAC: 00000015
[    0.000000] Process swapper (pid: 0, stack limit = 0xc06b8220)
[    0.000000] Stack: (0xc06b9f38 to 0xc06ba000)
[    0.000000] 
9f20:                                                       ffffffff 
c0700000
[    0.000000] 9f40: ffff1000 0002f7ff 00001000 00000007 c069e348 
c069454c c0712f68 c06be514
[    0.000000] 9f60: c06c2dc0 c06be514 0000000c c069514c c069e348 
c0679448 ffffffff 10c5387d
[    0.000000] 9f80: 414fc091 00000000 00000000 c005aa68 c05c38cc 
c06b9fb4 00000000 00000000
[    0.000000] 9fa0: 00000001 ffffffff c06f4380 00000000 414fc091 
00000000 00000000 c067693c
[    0.000000] 9fc0: 00000000 00000000 00000000 00000000 00000000 
c06a9288 00000000 c06f4614
[    0.000000] 9fe0: c06ba4c0 c06a9284 c06be624 0000406a 00000000 
0000807c 00000000 00000000
[    0.000000] [<c04d960c>] (fdt_check_header) from [<c039419c>] 
(__unflatten_device_tree+0x1c/0x12c)
[    0.000000] [<c039419c>] (__unflatten_device_tree) from [<c069514c>] 
(unflatten_device_tree+0x1c/0x34)
[    0.000000] [<c069514c>] (unflatten_device_tree) from [<c0679448>] 
(setup_arch+0x6e8/0x970)
[    0.000000] [<c0679448>] (setup_arch) from [<c067693c>] 
(start_kernel+0x88/0x3c0)
[    0.000000] [<c067693c>] (start_kernel) from [<0000807c>] (0x807c)
[    0.000000] Code: e3e0300d eafbbec4 e3e0300d eafbbec9 (e5903000)
[    0.000000] ---[ end trace cb88537fdc8fa200 ]---
[    0.000000] Kernel panic - not syncing: Attempted to kill the idle task!
[    0.000000] ---[ end Kernel panic - not syncing: Attempted to kill 
the idle task!

Do you have an idea what I'm doing wrong here? With the SDK U-Boot 
everything works fine.

Best regards,
Stefan