[PATCH] Modify raspberrypi mm_config_table to map GPIO and registers.

[Gedare Bloom]

On Mon, Oct 14, 2013 at 11:54 AM, Hesham Moustafa
<heshamelmatary at gmail.com> wrote:
>
>
>
> On Mon, Oct 14, 2013 at 4:02 PM, Sebastian Huber
> <sebastian.huber at embedded-brains.de> wrote:
>>
>> On 2013-10-14 15:34, Hesham AL-Matary wrote:
>>>
>>> diff --git a/c/src/lib/libbsp/arm/raspberrypi/startup/mm_config_table.c
>>> b/c/src/lib/libbsp/arm/raspberrypi/startup/mm_config_table.c
>>> index 5436a76..2b748b2 100644
>>> --- a/c/src/lib/libbsp/arm/raspberrypi/startup/mm_config_table.c
>>> +++ b/c/src/lib/libbsp/arm/raspberrypi/startup/mm_config_table.c
>>> @@ -42,7 +42,7 @@ bsp_mm_config_table[] = {
>>>     }, {
>>>       .begin = (uint32_t) bsp_section_text_begin,
>>>       .end = (uint32_t) bsp_section_text_end,
>>> -    .flags = ARMV7_MMU_CODE_CACHED
>>> +    .flags = ARMV7_MMU_READ_WRITE
>>
>>
>> What is the problem with the cache?  Did the cache previously work?
>
> There is a problem with applying a Read-Only permissions in general to this
> area for RaspberryPi BSP.
Any idea why? Letting the text region be read-write is overly
permissive, as RTEMS does not generally use self-modifying code.

>>
>>
>>
>>>     }, {
>>>       .begin = (uint32_t) bsp_section_rodata_begin,
>>>       .end = (uint32_t) bsp_section_rodata_end,
>>> @@ -63,8 +63,12 @@ bsp_mm_config_table[] = {
>>>       .begin = (uint32_t) bsp_section_stack_begin,
>>>       .end = (uint32_t) bsp_section_stack_end,
>>>       .flags = MMU_DATA_READ_WRITE
>>> +  }, {
>>> +    .begin = 0x20000000,
>>> +    .end = 0x20FFFFFF,
>>> +    .flags = ARMV7_MMU_DATA_READ_WRITE
>>
>>
>> What is this for an area?
>
> It's for Raspberry GPIO pins and other registers (defined at
> raspbberrypi.h).
>>
>>
>>>     }
>>>   };
>>
>>
>>
>> --
>> Sebastian Huber, embedded brains GmbH
>>
>> Address : Dornierstr. 4, D-82178 Puchheim, Germany
>> Phone   : +49 89 189 47 41-16
>> Fax     : +49 89 189 47 41-09
>> E-Mail  : sebastian.huber at embedded-brains.de
>> PGP     : Public key available on request.
>>
>> Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG.
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>
>
>
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