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

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

[Alex Deucher]

From: Harry Wentland <harry.wentland@amd.com>

This reverts commit 96cb7cf13d8530099c256c053648ad576588c387.

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

Cc: Alexander Monakov <amonakov@ispras.ru>
Cc: Hersen Wu <hersenxs.wu@amd.com>
Cc: Anthony Koo <Anthony.Koo@amd.com>
Cc: Michael Chiu <Michael.Chiu@amd.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reported-and-tested-by: Alexander Monakov <amonakov@ispras.ru>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
(cherry picked from commit 14ed1c908a7a623cc0cbf0203f8201d1b7d31d16)
---

Fixed up to apply cleanly on 5.7 and older kernels.

 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 7fc15b82fe48..f9f02e08054b 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -1334,7 +1334,7 @@ static int dm_late_init(void *handle)
 	unsigned int linear_lut[16];
 	int i;
 	struct dmcu *dmcu = adev->dm.dc->res_pool->dmcu;
-	bool ret = false;
+	bool ret;
 
 	for (i = 0; i < 16; i++)
 		linear_lut[i] = 0xFFFF * i / 15;
@@ -1350,13 +1350,10 @@ 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);
 }
-- 
2.25.4

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

[Greg KH]

On Mon, Jun 22, 2020 at 12:37:06PM -0400, Alex Deucher wrote:
> From: Harry Wentland <harry.wentland@amd.com>
> 
> This reverts commit 96cb7cf13d8530099c256c053648ad576588c387.
> 
> This change was used for DCN2 bringup and is no longer desired.
> In fact it breaks backlight on DCN2 systems.
> 
> Cc: Alexander Monakov <amonakov@ispras.ru>
> Cc: Hersen Wu <hersenxs.wu@amd.com>
> Cc: Anthony Koo <Anthony.Koo@amd.com>
> Cc: Michael Chiu <Michael.Chiu@amd.com>
> Signed-off-by: Harry Wentland <harry.wentland@amd.com>
> Acked-by: Alex Deucher <alexander.deucher@amd.com>
> Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
> Reported-and-tested-by: Alexander Monakov <amonakov@ispras.ru>
> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
> Cc: stable@vger.kernel.org
> (cherry picked from commit 14ed1c908a7a623cc0cbf0203f8201d1b7d31d16)
> ---
> 
> Fixed up to apply cleanly on 5.7 and older kernels.

Thanks, now queued up.

greg k-h