Re: [alsa-devel] How to handle parameter variation across different boards but same platform
On Thursday 05 July 2012, Vaibhav Hiremath wrote:
On 7/4/2012 7:57 PM, Mark Brown wrote:
On Wed, Jul 04, 2012 at 02:17:48PM +0000, Hebbar, Gururaja wrote:
On Wed, Jul 04, 2012 at 19:31:18, Mark Brown wrote:
If these are totally different boards they should have different machine IDs set so machine_is_() should identify. If that isn't there then you need to do something custom to your products to identify the boards further.
They are different boards with same SoC (AM33xx). So they both are true for machine_is_am33xx().
What if the device only supports Linux boot from DT, where we set machine_desc.nr = ~0 ??
Does machine ID still gets set? May be I am missing something...
No, it doesn't.
As part of my debugging, on AM335xEVM platform machine_is_am33xx() returns false, since the value of machine_desc.nr is set to ~0.
Correct. However, when you are booting using the device tree, parameters such as the clock frequency of a device should be encoded in the device tree itself, so you don't need to know which machine you are on.
Arnd
On Thu, Jul 05, 2012 at 08:32:16AM +0000, Arnd Bergmann wrote:
On Thursday 05 July 2012, Vaibhav Hiremath wrote:
Does machine ID still gets set? May be I am missing something...
No, it doesn't.
This is a *really* unfortunate decision, BTW - it means that if your bootloader has a device tree available it needs to know if the kernel it's booting is DT or non-DT which is just generally unhelpful. Sadly I don't hold out much hope of being able to fix it, though.
participants (2)
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Arnd Bergmann -
Mark Brown