[PATCH 2/5] drm/amdgpu: Init pcie_index/data address as fallback

[Zhang, Hawking]

[AMD Official Use Only - General]

Sure, will do in v2

Regards,
Hawking

-----Original Message-----
From: Alex Deucher <alexdeucher at gmail.com>
Sent: Wednesday, January 3, 2024 03:44
To: Zhang, Hawking <Hawking.Zhang at amd.com>
Cc: amd-gfx at lists.freedesktop.org; Zhou1, Tao <Tao.Zhou1 at amd.com>; Yang, Stanley <Stanley.Yang at amd.com>; Wang, Yang(Kevin) <KevinYang.Wang at amd.com>; Chai, Thomas <YiPeng.Chai at amd.com>; Li, Candice <Candice.Li at amd.com>; Deucher, Alexander <Alexander.Deucher at amd.com>; Ma, Le <Le.Ma at amd.com>; Lazar, Lijo <Lijo.Lazar at amd.com>
Subject: Re: [PATCH 2/5] drm/amdgpu: Init pcie_index/data address as fallback

On Mon, Jan 1, 2024 at 10:50 PM Hawking Zhang <Hawking.Zhang at amd.com> wrote:
>
> To allow using this helper for indirect access when nbio funcs is not
> available. For instance, in ip discovery phase.
>
> Signed-off-by: Hawking Zhang <Hawking.Zhang at amd.com>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 20 +++++++++++++++-----
>  1 file changed, 15 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index 001a35fa0f19..873419a5b9aa 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -781,12 +781,22 @@ u32 amdgpu_device_indirect_rreg_ext(struct amdgpu_device *adev,
>         void __iomem *pcie_index_hi_offset;
>         void __iomem *pcie_data_offset;
>
> -       pcie_index = adev->nbio.funcs->get_pcie_index_offset(adev);
> -       pcie_data = adev->nbio.funcs->get_pcie_data_offset(adev);
> -       if ((reg_addr >> 32) && (adev->nbio.funcs->get_pcie_index_hi_offset))
> -               pcie_index_hi = adev->nbio.funcs->get_pcie_index_hi_offset(adev);
> -       else
> +       if (unlikely(!adev->nbio.funcs)) {
> +               pcie_index = (0x38 >> 2);
> +               pcie_data = (0x3C >> 2);
> +       } else {
> +               pcie_index = adev->nbio.funcs->get_pcie_index_offset(adev);
> +               pcie_data = adev->nbio.funcs->get_pcie_data_offset(adev);
> +       }
> +
> +       if (reg_addr >> 32) {
> +               if (unlikely(!adev->nbio.funcs))
> +                       pcie_index_hi = (0x44 >> 2);

I'd still use a define for these, E.g.,

#define AMDGPU_PCIE_INDEX_FALLBACK (0x38 >> 2) etc.
Or something similar.

Alex

> +               else
> +                       pcie_index_hi = adev->nbio.funcs->get_pcie_index_hi_offset(adev);
> +       } else {
>                 pcie_index_hi = 0;
> +       }
>
>         spin_lock_irqsave(&adev->pcie_idx_lock, flags);
>         pcie_index_offset = (void __iomem *)adev->rmmio + pcie_index *
> 4;
> --
> 2.17.1
>