[PATCH] Revert "drm/amd/display: disable dcn20 abm feature for bring up"

[Alexander Monakov]

On Thu, 28 May 2020, Harry Wentland wrote:

> This reverts commit 96cb7cf13d8530099c256c053648ad576588c387.
> 
> This change was used for DCN2 bringup and is no longer desired.
> In fact it breaks backlight on DCN2 systems.

Reported-and-tested-by: Alexander Monakov <amonakov at ispras.ru>

Thanks.

> Cc: Alexander Monakov <amonakov at ispras.ru>
> Cc: Hersen Wu <hersenxs.wu at amd.com>
> Cc: Anthony Koo <Anthony.Koo at amd.com>
> Cc: Michael Chiu <Michael.Chiu at amd.com>
> Signed-off-by: Harry Wentland <harry.wentland at amd.com>
> ---
>  drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 11 ++++-------
>  1 file changed, 4 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index ddc979e3eebe..acd4874e0743 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -1356,7 +1356,7 @@ static int dm_late_init(void *handle)
>  	unsigned int linear_lut[16];
>  	int i;
>  	struct dmcu *dmcu = NULL;
> -	bool ret = false;
> +	bool ret;
>  
>  	if (!adev->dm.fw_dmcu)
>  		return detect_mst_link_for_all_connectors(adev->ddev);
> @@ -1377,13 +1377,10 @@ static int dm_late_init(void *handle)
>  	 */
>  	params.min_abm_backlight = 0x28F;
>  
> -	/* todo will enable for navi10 */
> -	if (adev->asic_type <= CHIP_RAVEN) {
> -		ret = dmcu_load_iram(dmcu, params);
> +	ret = dmcu_load_iram(dmcu, params);
>  
> -		if (!ret)
> -			return -EINVAL;
> -	}
> +	if (!ret)
> +		return -EINVAL;
>  
>  	return detect_mst_link_for_all_connectors(adev->ddev);
>  }
>