[U-Boot] [PATCH 1/3] arm: add CONFIG_MACH_TYPE option and documentation

[Igor Grinberg]

On 07/05/11 00:06, Christopher Harvey wrote:

> On Mon, Jul 04, 2011 at 12:00:19PM +0300, Igor Grinberg wrote:
>> CONFIG_MACH_TYPE can be used to set the machine type number in the
>> common arm code instead of setting it in the board code.
>>
>> Signed-off-by: Igor Grinberg <grinberg at compulab.co.il>
>> ---
>>  README               |   12 ++++++++++++
>>  arch/arm/lib/board.c |    5 +++++
>>  2 files changed, 17 insertions(+), 0 deletions(-)
>>
>> diff --git a/README b/README
>> index 446966d..a9ccb0a 100644
>> --- a/README
>> +++ b/README
>> @@ -442,6 +442,18 @@ The following options need to be configured:
>>  		crash. This is needed for buggy hardware (uc101) where
>>  		no pull down resistor is connected to the signal IDE5V_DD7.
>>  
>> +		CONFIG_MACH_TYPE		[relevant for ARM only]
>> +
>> +		This option can be used to specify the machine type number
>> +		as it appears in the ARM machine registry
>> +		(see http://www.arm.linux.org.uk/developer/machines/).
>> +		If this option is not defined, then your board code
>> +		will have to set this up like:
>> +		gd->bd->bi_arch_number = <mach type>;
>> +		Note: This option is not suitable if you have multiple
>> +		boards supported in a single configuration file and the
>> +		machine type is runtime discoverable.
>> +
>>  - vxWorks boot parameters:
>>  
>>  		bootvx constructs a valid bootline using the following
>> diff --git a/arch/arm/lib/board.c b/arch/arm/lib/board.c
>> index 169dfeb..ee77d05 100644
>> --- a/arch/arm/lib/board.c
>> +++ b/arch/arm/lib/board.c
>> @@ -451,6 +451,11 @@ void board_init_r (gd_t *id, ulong dest_addr)
>>  
>>  	monitor_flash_len = _end_ofs;
>>  	debug ("monitor flash len: %08lX\n", monitor_flash_len);
>> +
>> +#ifdef CONFIG_MACH_TYPE
>> +	bd->bi_arch_number = CONFIG_MACH_TYPE; /* board id for Linux */
>> +#endif
>> +
>>  	board_init();	/* Setup chipselects */
>>  
>>  #ifdef CONFIG_SERIAL_MULTI
>> -- 
>> 1.7.3.4
>>
> I'm curious, is it a feature that bd->bi_arch_number can be set at
> runtime?

Yes, it is a feature, as Wolfgang already said.

> Do any boards actually make a decision about what value to
> set this to?

Currently, at least, 2 boards (cm_t35 and keymile) use this feature.
This does not mean that in the future there will be no more boards using it.

> If not, then maybe it should be a required value.  I've
> submitted some patches that deal with the same sort of issue, so I'm
> interested in seeing that happens to this one.

If you're talking about this:
"Make u-boot a bit easier for newbies to port",
then no you are wrong, this patch has nothing to do with your patch,
it does completely another thing (see the subject).

-- 
Regards,
Igor.