[U-Boot] Rejected: PATCH Nios2 kernel bootstrap error due to missing processor data cache flush: fix

Renato Andreola
2009-07-22T08:01:10Z

Ok, please update the file with the correct bug fix with no more copyright.
My intent is only to fix the bug that caused random boot failures and to
keep free the good work on Nios2.

I was warried about that the official main UBoot distribution contained
a bug that has a big impact on the ability of someone to test a linux
distribution on Nios2 with UBoot.

We have spent two weeks with low level prints to find that the bug was
related to the missing data cache flush and not to the kernel or the
pre-kernel "trampoline" code.

Please note that the other bug related to incorrect flash timeout into
the CFI flash code has not been applied into the last Uboot release yet.
That bug was related to an integer division that leads to a zero timeout
in case of a less that 1000Hz timer (e.g: if the calculated timer
frequency is 999.99Hz, due to a truncation into the macro definition,
the resulting time to sleep is Zero: this brings to non reliable
clear/program cycles in Intel/Numonyx flash chips that works with the
status flag polling algorithm).

Regards,
Renato

Scott McNutt wrote:
> See comments.
>
>> diff --git a/lib_nios2/bootm.c b/lib_nios2/bootm.c
>> index 53fd569..1e8034b 100644
>> --- a/lib_nios2/bootm.c
>> +++ b/lib_nios2/bootm.c
>> @@ -2,6 +2,9 @@
>> * (C) Copyright 2003, Psyent Corporation <www.psyent.com>
>> * Scott McNutt <smcnutt@psyent.com>
>> *
>> + * (C) Copyright 2009, Imagos sas <www.imagos.it>
>> + * Renato Andreola <renato.andreola@imagos.it>
>> + *
>
> Claiming a copyright ...
>
>> + /* flushes data and instruction caches before calling the kernel */
>> + flush_dcache (0,CONFIG_SYS_DCACHE_SIZE );
>> + flush_icache (0,CONFIG_SYS_ICACHE_SIZE);
>
> ... for a two line bug fix?
>
> This is hardly a valid reason to claim copyright on the module.
>
> This practice will only discourage the contribution of original work
> to the project. Nobody wants to have their work hijacked in such a
> manner.
>
> Please resubmit.
>
> Regards,
> --Scott
>
>