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

[Christian König]

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.

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

Christian.