[PATCH] drm/amdgpu: modify system reference clock source for navi+

[Huang Rui]

On Tue, May 18, 2021 at 02:26:03PM +0800, Liu, Aaron wrote:
> Starting from Navi+, the rlc reference clock is used for system clock
> from vbios gfx_info table. It is incorrect to use core_refclk_10khz of
> vbios smu_info table as system clock.
> 
> Signed-off-by: Aaron Liu <aaron.liu at amd.com>

Acked-by: Huang Rui <ray.huang at amd.com>

> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_atomfirmware.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_atomfirmware.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_atomfirmware.c
> index 8c417014ca89..83ca58426139 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_atomfirmware.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_atomfirmware.c
> @@ -546,6 +546,21 @@ int amdgpu_atomfirmware_get_clock_info(struct amdgpu_device *adev)
>  		ret = 0;
>  	}
>  
> +	/* if asic is Navi+, the rlc reference clock is used for system clock
> +	 * from vbios gfx_info table */
> +	if (adev->asic_type >= CHIP_NAVI10) {
> +		index = get_index_into_master_table(atom_master_list_of_data_tables_v2_1,
> +						   gfx_info);
> +		if (amdgpu_atom_parse_data_header(mode_info->atom_context, index, NULL,
> +					  &frev, &crev, &data_offset)) {
> +			struct atom_gfx_info_v2_2 *gfx_info = (struct atom_gfx_info_v2_2*)
> +				(mode_info->atom_context->bios + data_offset);
> +			if ((frev >= 2) && (crev >= 2))
> +				spll->reference_freq = le32_to_cpu(gfx_info->rlc_gpu_timer_refclk);
> +			ret = 0;
> +		}
> +	}
> +
>  	return ret;
>  }
>  
> -- 
> 2.25.1
>