[Why]
With kernel module parameter "freesync_video" is enabled, if the mode
is changed to preferred mode(the mode with highest rate), then Freesync
fails because the preferred mode is treated as one of freesync video
mode, and then be configurated as freesync video mode(fixed refresh
rate).

[How]
Skip freesync fixed rate configurating when modeset to preferred mode.
Signed-off-by: NSolomon Chiu <solomon.chiu@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

DMUB firmware info is printed before it gets initialized.
Correct this order to ensure true value is conveyed.
Signed-off-by: NShirish S <shirish.s@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

[Why]
Display Manager initializes array of vblank workqueues, but only 1 is used.

[How]
Use single instance init instead of array.
Reviewed-by: NQingqing Zhou <Qingqing.Zhuo@amd.com>
Acked-by: NAurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: NRoman Li <Roman.Li@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

On platforms that support multiple backlights, register
each one separately.  This lets us manage them independently
rather than registering a single backlight and applying the
same settings to both.

v2: fix typo:
Reported-by: Nkernel test robot <lkp@intel.com>
Reviewed-by: NRoman Li <Roman.Li@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

We've gotten a number of reports about backlight control not
working on panels which indicate that they use aux backlight
control.  A recent patch:

commit 2d73eabe
Author: Camille Cho <Camille.Cho@amd.com>
Date:   Thu Jul 8 18:28:37 2021 +0800

    drm/amd/display: Only set default brightness for OLED

    [Why]
    We used to unconditionally set backlight path as AUX for panels capable
    of backlight adjustment via DPCD in set default brightness.

    [How]
    This should be limited to OLED panel only since we control backlight via
    PWM path for SDR mode in LCD HDR panel.
Reviewed-by: NKrunoslav Kovac <krunoslav.kovac@amd.com>
Acked-by: NRodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: NCamille Cho <Camille.Cho@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Changes some other code to only use aux for backlight control on
OLED panels.  The commit message seems to indicate that PWM should
be used for SDR mode on HDR panels.  Do something similar for
backlight control in general.  This may need to be revisited if and
when HDR started to get used.

Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1438
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=213715Reviewed-by: NRoman Li <Roman.Li@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Fix make htmldocs complaint:
./drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c:628: warning: Excess function parameter 'interrupt_params' description in 'DMUB_TRACE_MAX_READ'

v2:
Moved DMUB_TRACE_MAX_READ macro above function documentation
Signed-off-by: NAnson Jacob <Anson.Jacob@amd.com>
CC: Harry Wentland <harry.wentland@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NHarry Wentland <harry.wentland@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

[Why&How]
Print a debug message when dcc validation fails in the display driver.
Most DCC enablement related errors are from userspace. Adding a debug
print in case of a failure from display driver will aid quicker triage.
Reviewed-by: NHarry Wentland <Harry.Wentland@amd.com>
Acked-by: NRodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: NAurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Don't populate the const array common_rates on the stack but instead it
static. Makes the object code smaller by 80 bytes:

Before:
   text	   data	    bss	    dec	    hex	filename
 268019	  98322	    256	 366597	  59805	../display/amdgpu_dm/amdgpu_dm.o

After:
   text	   data	    bss	    dec	    hex	filename
 267843	  98418	    256	 366517	  597b5	../display/amdgpu_dm/amdgpu_dm.o

Reduction of 80 bytes

(gcc version 10.3.0)
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

For the unknown CEA parse case on DMUB-enabled ASICs, dmesg will
print an error message like below, this will be captured by
automation tools as it has the word like ERROR during boot up
and treated as a false error, as it does not break bootup process.
So use DRM_WARN printing for this.

[drm:amdgpu_dm_update_freesync_caps [amdgpu]] *ERROR* Unknown EDID CEA parser results

v2: Use DRM_WARN to print such info.
Signed-off-by: NGuchun Chen <guchun.chen@amd.com>
Reviewed-by: NStylon Wang <stylon.wang@amd.com>
Reviewed-by: NHarry Wentland <harry.wentland@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

[Why]
The original logic is to update eDP's backlight level
on every amdgpu dm atomic commit, which causes excessive
DMUB write. As a result, when playing game or moving window
around, DMUB timeout and system lagging are observed.

[How]
We only need to update eDP's backlight level when current level
doesn't match requested level.
Signed-off-by: NZhan Liu <zhan.liu@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

[Why]
The original logic is to update eDP's backlight level
on every amdgpu dm atomic commit, which causes excessive
DMUB write. As a result, when playing game or moving window
around, DMUB timeout and system lagging are observed.

[How]
We only need to update eDP's backlight level when current level
doesn't match requested level.
Signed-off-by: NZhan Liu <zhan.liu@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

[Why]
Changes in DM needed to support Freesync HDMI on DMUB.

[How]
Change implementation to parse CEA blocks in case of DMUB-enabled ASICs.
Signed-off-by: NStylon Wang <stylon.wang@amd.com>
Reviewed-by: NNicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: NRodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Tested-by: NDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Remove unused variable.

Fixes: e7d9560a ("Revert "drm/amd/display: Fix overlay validation by considering cursors"")
Reviewed-by: NHarry Wentland <harry.wentland@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

This reverts commit 33f409e6.

The patch that we are reverting here was originally applied because it
fixes multiple IGT issues and flickering in Android. However, after a
discussion with Sean Paul and Mark, it looks like that this patch might
cause problems on ChromeOS. For this reason, we decided to revert this
patch.

Cc: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Cc: Harry Wentland <Harry.Wentland@amd.com>
Cc: Hersen Wu <hersenxs.wu@amd.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Mark Yacoub <markyacoub@chromium.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NRodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Reviewed-by: NSean Paul <seanpaul@chromium.org>
Reviewed-by: NHarry Wentland <harry.wentland@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

[Why]
Sometimes, DP receiver chip power-controlled externally by an
Embedded Controller could be treated and used as eDP,
if it drives mobile display. In this case,
we shouldn't be doing power-sequencing, hence we can skip
waiting for T7-ready and T9-ready."

[How]
Added a feature mask to enable eDP no power sequencing feature.

To enable this, set 0x10 flag in amdgpu.dcfeaturemask on
Linux command line.
Signed-off-by: NZhan Liu <zhan.liu@amd.com>
Reviewed-by: NNikola Cornij <Nikola.Cornij@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

No need for a separate flag now that DCN3.1 is not in bring up.
Fold into DRM_AMD_DC_DCN like previous DCN IPs.
Reviewed-by: NNicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

[Why]
After panel power up, if PSR entry attempted too early,
PSR state may get stuck in transition.
This could happen if the panel is not ready
to respond to the SDP PSR entry message.
In this case dmub f/w is unable to abort PSR entry
since abortion is not permitted after the SDP has been sent.

[How]
Skip 5 pageflips before PSR enable.
Signed-off-by: NRoman Li <roman.li@amd.com>
Reviewed-by: NHersen Wu <hersenxs.wu@amd.com>
Acked-by: NBindu Ramamurthy <bindu.r@amd.com>
Tested-by: NDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Recently, we added support for an experimental feature named Freesync
video; for more details on that, refer to:

commit 6f59f229 ("drm/amd/display: Skip modeset for front porch change")
commit d10cd527 ("drm/amd/display: Add freesync video modes based on preferred modes")
commit 0eb1af2e ("drm/amd/display: Add module parameter for freesync video mode")

Nevertheless, we did not document it in detail in our driver. This
commit introduces a kernel-doc and expands the module parameter
description.

Cc: Aurabindo Pillai <aurabindo.pillai@amd.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: NRodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Reviewed by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

[Why]
Improve the maintain/read abilities of dm code.

[How]
Create amdgpu_dm_psr.c/h files.
Move psr function from amdgpu_dm.c
Signed-off-by: NRoman Li <roman.li@amd.com>
Reviewed-by: NNicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: NAnson Jacob <Anson.Jacob@amd.com>
Tested-by: NDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

For each CRTC state, check the size of Gamma and Degamma LUTs  so
unexpected and larger sizes wouldn't slip through.

TEST: IGT:kms_color::pipe-invalid-gamma-lut-sizes

v2: fix assignments in if clauses, Mark's email.
Reviewed-by: NHarry Wentland <harry.wentland@amd.com>
Signed-off-by: NMark Yacoub <markyacoub@chromium.org>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

[Why]
We update scaling settings when scaling mode has been changed.
However when changing mode from native resolution the scaling mode previously
set gets ignored.

[How]
Perform scaling settings update on modeset.
Signed-off-by: NRoman Li <roman.li@amd.com>
Reviewed-by: NNicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: NStylon Wang <stylon.wang@amd.com>
Tested-by: NDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

The functions can be called both in _rcu context as well
as while holding the lock.

v2: add some kerneldoc as suggested by Daniel
v3: fix indentation
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NJason Ekstrand <jason@jlekstrand.net>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210602111714.212426-7-christian.koenig@amd.com

To detect DCN3.1 ASICs and to enable the appropriate number of CRTCs,
pick the right validation paths for display formats and to use the
right DC interfaces.
Acked-by: NHuang Rui <ray.huang@amd.com>
Signed-off-by: NNicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

This allows to tie the log message to a specific DRM device.
Signed-off-by: NSimon Ser <contact@emersion.fr>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Harry Wentland <hwentlan@amd.com>
Cc: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: NBas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

[Why]
On resume we perform DMUB hw_init which allocates memory:
dm_resume->dm_dmub_hw_init->dc_dmub_srv_create->kzalloc
That results in memory leak in suspend/resume scenarios.

[How]
Allocate memory for the DC wrapper to DMUB only if it was not
allocated before.
No need to reallocate it on suspend/resume.
Signed-off-by: NLang Yu <Lang.Yu@amd.com>
Signed-off-by: NRoman Li <roman.li@amd.com>
Reviewed-by: NNicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: NQingqing Zhuo <qingqing.zhuo@amd.com>
Tested-by: NDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

A few weeks ago, we saw a two cursor issue in a ChromeOS system. We
fixed it in the commit:

 drm/amd/display: Fix two cursor duplication when using overlay
 (read the commit message for more details)

After this change, we noticed that some IGT subtests related to
kms_plane and kms_plane_scaling started to fail. After investigating
this issue, we noticed that all subtests that fail have a primary plane
covering the overlay plane, which is currently rejected by amdgpu dm.
Fail those IGT tests highlight that our verification was too broad and
compromises the overlay usage in our drive. This patch fixes this issue
by ensuring that we only reject commits where the primary plane is not
fully covered by the overlay when the cursor hardware is enabled. With
this fix, all IGT tests start to pass again, which means our overlay
support works as expected.

Cc: Tianci.Yin <tianci.yin@amd.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Nicholas Choi <nicholas.choi@amd.com>
Cc: Bhawanpreet Lakha <bhawanpreet.lakha@amd.com>
Cc: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Cc: Mark Yacoub <markyacoub@google.com>
Cc: Daniel Wheeler <daniel.wheeler@amd.com>
Tested-by: NDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: NRodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

[Why]
FS video support regressed GPU scaling and the scaled buffer ends up
stuck in the top left of the screen at native size - full, aspect,
center scaling modes do not function.

This is because decide_crtc_timing_for_drm_display_mode() does not
get called when scaling is enabled.

[How]
Split recalculate timing and scaling into two different flags.

We don't want to call drm_mode_set_crtcinfo() for scaling, but we
do want to call it for FS video.

Optimize and move preferred_refresh calculation next to
decide_crtc_timing_for_drm_display_mode() like it used to be since
that's not used for FS video.

We don't need to copy over the VIC or polarity in the case of FS video
modes because those don't change.

Fixes: 6f59f229 ("drm/amd/display: Skip modeset for front porch change")

Cc: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: NNicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: NAurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drm/amd/display: fix warning: ‘update_dsc_caps’ and ‘apply_dsc_policy_for_stream’ defined but not used

Fixes gcc '-Wunused-function' warning:

‘update_dsc_caps’ and ‘apply_dsc_policy_for_stream’ are only used
if 'CONFIG_DRM_AMD_DC_DCN' is defined,

however, it's defined even if 'CONFIG_DRM_AMD_DC_DCN' is not defined.
Thus gcc will report following warning
if 'CONFIG_DRM_AMD_DC_DCN' is not defined:

drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:5572:13: warning:
‘apply_dsc_policy_for_stream’ defined but not used [-Wunused-function]

drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:5556:13: warning:
‘update_dsc_caps’ defined but not used [-Wunused-function]

Thus move the definition of ‘update_dsc_caps’ and
‘apply_dsc_policy_for_stream’ inside define macro to fix it.
Signed-off-by: NBaokun Li <libaokun1@huawei.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

define a new macro for_each_new_plane_in_state_reverse to replace
for_each_oldnew_plane_in_state_reverse, so that the unused variable
'old_plane_state' can be removed.

Fix gcc warning:
drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:10066:26: warning:
 variable ‘old_plane_state’ set but not used [-Wunused-but-set-variable]
Signed-off-by: NYu Kuai <yukuai3@huawei.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

This allows to tie the log message to a specific DRM device.
Signed-off-by: NSimon Ser <contact@emersion.fr>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Harry Wentland <hwentlan@amd.com>
Cc: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: NBas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Use WARN_ON() inside if-condition when possible.

v2: Squash in coding style fix (Alex)
Signed-off-by: NNirmoy Das <nirmoy.das@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

WARN_ON() will not kill the process so the second WARN_ON()
will try to dereference NULL pointer.
Signed-off-by: NNirmoy Das <nirmoy.das@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

This is intended to enable direct high-precision scanout and pageflip
of Vulkan swapchain images in format VK_FORMAT_R16G16B16A16_UNORM.

Expose DRM_FORMAT_XRGB16161616, DRM_FORMAT_ARGB16161616,
DRM_FORMAT_XBGR16161616 and DRM_FORMAT_ABGR16161616 as 16 bpc
unsigned normalized formats. These allow to take full advantage
of the maximum precision of the display hardware, ie. currently
up to 12 bpc.

Searching through old AMD M56, M76 and RV630 hw programming docs
suggests that these 16 bpc formats are supported by all DCE and
DCN display engines, so we can expose the formats unconditionally.

Successfully tested on AMD Polaris11 DCE-11.2 an RavenRidge DCN-1.0
with a HDR-10 monitor over 10 bpc DP output with spatial dithering
enabled by the driver. Picture looks good, and my photometer
measurement procedure confirms an effective 12 bpc color
reproduction.
Signed-off-by: NMario Kleiner <mario.kleiner.de@gmail.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

They are global ACPI methods, so maybe the structures
global in the driver. This simplified a number of things
in the handling of these methods.

v2: reset the handle if verify interface fails (Lijo)
v3: fix compilation when ACPI is not defined.
Reviewed-by: NLijo Lazar <lijo.lazar@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Fixes the following W=1 kernel build warning(s):

 drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:608: warning: Function parameter or member 'interrupt_params' not described in 'dm_dcn_vertical_interrupt0_high_irq'

Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Leo Li <sunpeng.li@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: amd-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Fixes the following W=1 kernel build warning(s):

 drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:608: warning: Function parameter or member 'interrupt_params' not described in 'dm_dcn_vertical_interrupt0_high_irq'

Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Leo Li <sunpeng.li@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: amd-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

[Why & How]
SST dsc determination policy becomes bigger when more scenarios
are introduced. Take it out to make it clean and readable.
Signed-off-by: NFangzhi Zuo <Jerry.Zuo@amd.com>
Reviewed-by: NNicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: NQingqing Zhuo <qingqing.zhuo@amd.com>
Tested-by: NDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

[Why & How]
To facilitate DSC debugging purpose
Signed-off-by: NFangzhi Zuo <Jerry.Zuo@amd.com>
Reviewed-by: NNicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: NQingqing Zhuo <qingqing.zhuo@amd.com>
Tested-by: NDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

[Why]
On resume we perform DMUB hw_init which allocates memory:
dm_resume->dm_dmub_hw_init->dc_dmub_srv_create->kzalloc
That results in memory leak in suspend/resume scenarios.

[How]
Allocate memory for the DC wrapper to DMUB only if it was not
allocated before.
No need to reallocate it on suspend/resume.
Signed-off-by: NLang Yu <Lang.Yu@amd.com>
Signed-off-by: NRoman Li <roman.li@amd.com>
Reviewed-by: NNicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: NQingqing Zhuo <qingqing.zhuo@amd.com>
Tested-by: NDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

[Why]
dc_dmub_srv_destroy() has internal null-check and null assignment.
No need to duplicate them externally.

[How]
Remove redundant safeguards.
Signed-off-by: NLang Yu <Lang.Yu@amd.com>
Signed-off-by: NRoman Li <roman.li@amd.com>
Reviewed-by: NNicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: NQingqing Zhuo <qingqing.zhuo@amd.com>
Tested-by: NDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>