[PATCH 4/6] drm/amdgpu: drop alpha support

[Michel Dänzer]

On 31/03/17 04:09 PM, Christian König wrote:
> Am 31.03.2017 um 03:07 schrieb Michel Dänzer:
>> On 30/03/17 10:09 PM, Alex Deucher wrote:
>>> On Thu, Mar 30, 2017 at 2:39 AM, Michel Dänzer <michel at daenzer.net>
>>> wrote:
>>>> On 29/03/17 09:55 PM, Christian König wrote:
>>>>> From: Christian König <christian.koenig at amd.com>
>>>>>
>>>>> We will probably never see this combination.
>>>>>
>>>>> Signed-off-by: Christian König <christian.koenig at amd.com>
>>>>> ---
>>>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 25
>>>>> -------------------------
>>>>>   1 file changed, 25 deletions(-)
>>>>>
>>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>>>> index 7bf5ba7..524abca 100644
>>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>>>> @@ -538,31 +538,6 @@ static int amdgpu_ttm_io_mem_reserve(struct
>>>>> ttm_bo_device *bdev, struct ttm_mem_
>>>>>                        return -EINVAL;
>>>>>                mem->bus.base = adev->mc.aper_base;
>>>>>                mem->bus.is_iomem = true;
>>>>> -#ifdef __alpha__
>>>>> -             /*
>>>>> -              * Alpha: use bus.addr to hold the ioremap() return,
>>>>> -              * so we can modify bus.base below.
>>>>> -              */
>>>>> -             if (mem->placement & TTM_PL_FLAG_WC)
>>>>> -                     mem->bus.addr =
>>>>> -                             ioremap_wc(mem->bus.base +
>>>>> mem->bus.offset,
>>>>> -                                        mem->bus.size);
>>>>> -             else
>>>>> -                     mem->bus.addr =
>>>>> -                             ioremap_nocache(mem->bus.base +
>>>>> mem->bus.offset,
>>>>> -                                             mem->bus.size);
>>>>> -             if (!mem->bus.addr)
>>>>> -                     return -ENOMEM;
>>>>> -
>>>>> -             /*
>>>>> -              * Alpha: Use just the bus offset plus
>>>>> -              * the hose/domain memory base for bus.base.
>>>>> -              * It then can be used to build PTEs for VRAM
>>>>> -              * access, as done in ttm_bo_vm_fault().
>>>>> -              */
>>>>> -             mem->bus.base = (mem->bus.base & 0x0ffffffffUL) +
>>>>> -                     adev->ddev->hose->dense_mem_base;
>>>>> -#endif
>>>>>                break;
>>>>>        default:
>>>>>                return -EINVAL;
>>>>>
>>>> Maybe leave an #error line, or make AMDGPU depend on !ALPHA in Kconfig,
>>>> to prevent somebody from trying this driver on an Alpha machine, and it
>>>> mysteriously failing due to the lack of this?
>>>>
>>>> Either way,
>>>>
>>>> Acked-by: Michel Dänzer <michel.daenzer at amd.com>
>>> Does this code even work on alpha (or compile for that matter)?
>> If it doesn't compile, that makes it obvious to somebody who tries
>> compiling it on Alpha that there's something wrong. Whereas if we just
>> remove it, the driver might build but probably won't work.
> 
> According to Wikipedia the last Alpha was build in 2004, the first GCN 1
> hardware we support shipped in 2014.
> 
> That's a decade between those and I have strong doubts that any Alpha
> board has physically PCIe compatible slots.

That's a good point about PCIe.

 git grep -i PCIe arch/alpha

in the kernel tree doesn't turn up anything.


> Anyway, I will just add a !ALPHA to Kconfig.

You've convinced me it's not necessary. The patch is

Reviewed-by: Michel Dänzer <michel.daenzer at amd.com>

as is.


-- 
Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer