Commit 46c3c32ba655 for kernel

commit 46c3c32ba655c94b885b75b5adb8e481612126bf
Author: Pengpeng Hou <pengpeng@iscas.ac.cn>
Date:   Thu Jun 25 14:06:47 2026 +0800

    drm/amd/display: wire DCN42B mcache programming callback

    DCN42B enables DML2 and DML21 by default and defines
    dcn42b_prepare_mcache_programming(), but the resource function table only
    wires the callback when CONFIG_DRM_AMD_DC_DML21 is defined.

    There is no in-tree Kconfig symbol named DRM_AMD_DC_DML21, so the
    preprocessor always removes the callback entry.  Sibling DCN42 and DCN401
    resource tables wire their prepare_mcache_programming callbacks
    unconditionally, and the core DC code already checks whether the callback
    pointer is present before calling it.

    Remove the stale guard so DCN42B exposes the callback relation that its
    source and DML21 build world already provide.

    This is an RFC patch draft from static conditional callback legality
    auditing.  It needs AMD display maintainer review before submission as a
    final fix.

    Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
    Reviewed-by: George Zhang <george.zhang@amd.com>
    Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
    (cherry picked from commit 85453fb4ff726e1ddb9984ee83dca260903c5353)

diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn42b/dcn42b_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn42b/dcn42b_resource.c
index e9c33e3466ea..94e166c0a9b0 100644
--- a/drivers/gpu/drm/amd/display/dc/resource/dcn42b/dcn42b_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/resource/dcn42b/dcn42b_resource.c
@@ -1900,9 +1900,7 @@ static struct resource_funcs dcn42b_res_pool_funcs = {
 	.update_soc_for_wm_a = dcn30_update_soc_for_wm_a,
 	.add_phantom_pipes = dcn32_add_phantom_pipes,
 	.calculate_mall_ways_from_bytes = dcn32_calculate_mall_ways_from_bytes,
-#ifdef CONFIG_DRM_AMD_DC_DML21
 	.prepare_mcache_programming = dcn42b_prepare_mcache_programming,
-#endif
 	.build_pipe_pix_clk_params = dcn42b_build_pipe_pix_clk_params,
 	.get_power_profile = dcn401_get_power_profile,
 	.get_vstartup_for_pipe = dcn401_get_vstartup_for_pipe,