drm/amd/display: Move the memory allocation out of dcn20_validate_bandwidth_fp().

dcn20_validate_bandwidth_fp() is invoked while FPU access has been
enabled. FPU access requires disabling preemption even on PREEMPT_RT.
It is not possible to allocate memory with disabled preemption even with
GFP_ATOMIC on PREEMPT_RT.

Move the memory allocation before FPU access is enabled.
To preserve previous "clean" state of "pipes" add a memset() before the
second invocation of dcn20_validate_bandwidth_internal() where the
variable is used.

Acked-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Move the memory allocation out of dcn21_validate_bandwidth_fp().

dcn21_validate_bandwidth_fp() is invoked while FPU access has been
enabled. FPU access requires disabling preemption even on PREEMPT_RT.
It is not possible to allocate memory with disabled preemption even with
GFP_ATOMIC on PREEMPT_RT.

Move the memory allocation before FPU access is enabled.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=217928
Acked-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Remove FPU operations from dcn201 resources

We have some FPU operations on the resource part of the DCN201. This
commit drops FPU flags and moves any required FPU code to the DML
folder.

Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Acked-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: move FPU code on dcn21 clk_mgr

The -mno-gnu-attribute option in dcn21 clk mgr makefile hides a soft vs
hard fp error for powerpc. After removing this flag, we can see some FPU
code remains there:

/gcc-11.3.0-nolibc/powerpc64-linux/bin/powerpc64-linux-ld:
drivers/gpu/drm/amd/amdgpu/../display/dc/dml/display_mode_lib.o uses
hard float,
drivers/gpu/drm/amd/amdgpu/../display/dc/clk_mgr/dcn21/rn_clk_mgr.o uses
soft float

Therefore, remove the -mno-gnu-attribute flag for dcn21/powerpc and move
FPU-associated code to DML folder.

Signed-off-by: Melissa Wen <mwen@igalia.com>
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: move FPU operations from dcn21 to dml/dcn20 folder

dml/dcn20_fpu file centralizes all DCN2x functions that require FPU access.
Therefore, this patch moves FPU-related code from dcn21 to dcn20_fpu. These
include:
- dcn21_populate_dml_pipes_from_context()
- dcn21_validate_bandwidth_fp() and related:
- dcn21_calculate_wm(),
- patch_bounding_box(),
- calculate_wm_set_for_vlevel()
- renaming update_bw_bounding_box() to dcn21_update_bw_bounding_box(), move
to dcn20_fpu with related static function construct_low_pstate_lvl()

Also, make dcn21_fast_validate_bw() public in dcn21_resource as it is called
by dcn21_validate_bandwidth_fp() now in dcn20_fpu.

Reuse dcn20_fpu_adjust_dppclk() in dcn21_fast_validate_bw() as it isolates
the same FPU operation.

Include dchubbub.h as it is required in dcn21_populate_dml_pipes_from_context()

Signed-off-by: Melissa Wen <mwen@igalia.com>
Acked-by: Alan Liu <HaoPing.Liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: move FPU-related code from dcn20 to dml folder

Move parts of dcn20 code that uses FPU to dml folder. It aims to isolate
FPU operations as described by series:

drm/amd/display: Introduce FPU directory inside DC
https://patchwork.freedesktop.org/series/93042/

This patch moves the following functions from dcn20_resource to
dml/dcn20_fpu and calls of public functions in dcn20_resource are
wrapped by DC_FP_START/END():

- void dcn20_populate_dml_writeback_from_context
- static bool is_dtbclk_required()
- static enum dcn_zstate_support_state()
- void dcn20_calculate_dlg_params()
- static void swizzle_to_dml_params()
- int dcn20_populate_dml_pipes_from_context()
- void dcn20_calculate_wm()
- void dcn20_cap_soc_clocks()
- void dcn20_update_bounding_box()
- void dcn20_patch_bounding_box()
- bool dcn20_validate_bandwidth_fp()

This movement also affects dcn21/30/31, as dcn20_calculate_dlg_params()
is used by them. For this reason, I included dcn20_fpu headers in
dcn20_resource headers to make dcn20_calculate_dlg_params() visible to
dcn21/30/31.

Three new functions are created to isolate well-delimited FPU
operations:

- void dcn20_fpu_set_wb_arb_params(): set cli_watermark,
pstate_watermark and time_per_pixel from wb_arb_params (struct
mcif_arb_params), since those uses FPU operations on double types:
WritebackUrgentWatermark, WritebackDRAMClockChangeWatermark, '16.0'.
- void dcn20_fpu_set_wm_ranges(): set min_fill_clk_mhz and
max_fill_clk_mhz involves FPU calcs on dram_speed_mts (double type);
- void dcn20_fpu_adjust_dppclk(): adjust operation on RequiredDPPCLK
that is a double.

Signed-off-by: Melissa Wen <mwen@igalia.com>
Acked-by: Alan Liu <HaoPing.Liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Re-arrange FPU code structure for dcn2x

[Why]
Current FPU code for DCN2x is located under dml/dcn2x.
This is not aligned with DC's general source tree
structure.

[How]
Move FPU code for DCN2x to dml/dcn20.

Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Acked-by: Solomon Chiu <solomon.chiu@amd.com>
Signed-off-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>