[linux-yocto] [kernel-cache][yocto-4.12][PATCH] features/i915/i915.cfg: compile i915 as a module

[Liwei Song]

On 12/06/2017 06:26 AM, Bruce Ashfield wrote:
> On 12/04/2017 08:16 PM, Liwei Song wrote:
>> Set i915 as a moudle to trigger the firmware load
> 
> typo: module
> 
>> at the same time the module is loaded.
>>
>> This can aviod i915 driver load rootfs's firmware before
>> rootfs was mounted error.
> 
> I'm not following this problem description, can you rephrase ?
> Is it a timing problem between the driving starting (as the
> built in) and it triggering a firmware load (that fails due
> to the rootfs not being ready) ?

Yes, it is a timing problem, how about rephrase it as following:

This can aviod a timing problem between the driver starting
and it triggering a firmware load, after compile it as module
i915 driver will start after the rootfs is ready, then the
firmware store in /lib/firmware/ can be load successful by
i915 driver.

 

> 
> presumably the i915 was built in for a reason, i.e. so it
> is available in early boot without the need to load a module.
> And this change would break that functionality. Also, are
> there any other build settings that need to arrange for the
> module autoload ?

I suppose no during my test on board.

Thanks,
Liwei.


> 
> Since there is that possibility, restating the problem you are
> trying to fix would be good.
> 
> Bruce
> 
>>
>> Signed-off-by: Liwei Song <liwei.song at windriver.com>
>> ---
>>   features/i915/i915.cfg | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/features/i915/i915.cfg b/features/i915/i915.cfg
>> index 6dcc60f2dfc7..60cb963e014b 100644
>> --- a/features/i915/i915.cfg
>> +++ b/features/i915/i915.cfg
>> @@ -8,6 +8,6 @@ CONFIG_AGP=y
>>   CONFIG_AGP_INTEL=y
>>   CONFIG_DRM=y
>>   CONFIG_DRM_KMS_HELPER=y
>> -CONFIG_DRM_I915=y
>> +CONFIG_DRM_I915=m
>>   CONFIG_DRM_KMS_FB_HELPER=y
>>   CONFIG_DRM_I915_ALPHA_SUPPORT=y
>>
> 
> 
>