[U-Boot] [PATCH v7 21/21] sf: Add SPI NOR protection mechanism

[Bin Meng]

Hi,

On Wed, Nov 11, 2015 at 10:04 PM, Fabio Estevam <festevam at gmail.com> wrote:
> On Wed, Nov 11, 2015 at 12:56 AM, Simon Glass <sjg at chromium.org> wrote:
>> Hi Fabio,
>>
>> On 10 November 2015 at 16:51, Fabio Estevam <festevam at gmail.com> wrote:
>>>
>>> Hi Simon,
>>>
>>> On Tue, Nov 10, 2015 at 10:09 PM, Simon Glass <sjg at chromium.org> wrote:
>>>
>>> > This patch breaks chromebook_link - I think because it adds a new
>>> > operation which is not supported by all flash chips. Those that are
>>> > not supported (i.e that don't have the 'flash_is_locked' method)
>>> > should still work.
>>>
>>> What is the symptom you are seeing? Which SPI NOR flash does this board have?
>>
>> It crashes reading the environment:
>>
>> U-Boot 2015.10-00544-gcad0499 (Nov 10 2015 - 17:06:00 -0700)
>>
>> CPU:   Intel(R) Core(TM) i5-3427U CPU @ 1.80GHz
>> DRAM:  2.7 GiB
>> SF: Detected W25Q64CV with page size 256 Bytes, erase size 4 KiB, total 8 MiB
>> *** Warning - bad CRC, using default environment
>>
>> Video: 1280x1024x16
>> Model: Google Link
>> SF: Detected W25Q64CV with page size 256 Bytes, erase size 4 KiB, total 8 MiB
>> Invalid Opcode (Undefined Opcode)
>
> I am wondering if this invalid opcode is caused by 6c2f758cee266f7648.
>
> Could you please try this?
>

No, this does not resolve this issue.

> --- a/arch/x86/include/asm/bitops.h
> +++ b/arch/x86/include/asm/bitops.h
> @@ -364,7 +364,7 @@ static __inline__ int ffs(int x)
>         __asm__("bsfl %1,%0\n\t"
>                 "jnz 1f\n\t"
>                 "movl $-1,%0\n"
> -               "1:" : "=r" (r) : "rm" (x));
> +               "1:" : "=r" (r) : "g" (x));
>
>         return r+1;
>  }

It turns out it is a NULL pointer exception! Fixing this NULL pointer
makes the crash disappear, but 'saveenv' does not actually work on the
SST flash. Something is broken again, gosh!

Regards,
Bin