Re: [PATCH v2 02/10] gpu: nova-core: Create initial Gsp
From: John Hubbard
Date: Wed Sep 24 2025 - 17:15:51 EST
On 9/24/25 2:07 PM, Lyude Paul wrote:
> On Wed, 2025-09-24 at 13:50 -0700, John Hubbard wrote:
>> On 9/24/25 1:13 PM, Lyude Paul wrote:
>>> Some comments down below
>> ...
>>>> +/// Creates a self-mapping page table for `obj` at its beginning.
>>>> +fn create_pte_array(obj: &mut CoherentAllocation<u8>) {
>>>> + let num_pages = obj.size().div_ceil(GSP_PAGE_SIZE);
>>>
>>> Unfortunately there's a bit of a gotcha here - we can't actually use functions
>>> like div_ceil as-is, because a number of 32 bit architectures do not support
>>> u64 / u64 natively. The problem is we don't have __aeabi_uldivmod implemented
>>
>> I recall that we agreed that nova will depend upon CONFIG_64BIT.
>>
>> Does that make this point N/A?
>
> Oh! I apologize, I must have actually missed that memo :). If we're defending
I do enjoy the "defending" stance, that somehow does feel quite
appropriate at times. :)
> on CONFIG_64BIT then that should be fine:
>
> Reviewed-by: Lyude Paul <lyude@xxxxxxxxxx>
I found the memo, here it is for future reference:
https://lore.kernel.org/all/DCHE7FOG5ONY.9SVQATXHGM9M@xxxxxxxxxx/
thanks,
--
John Hubbard