diff options
author | Rodrigo Siqueira <Rodrigo.Siqueira@amd.com> | 2020-04-29 10:53:02 -0400 |
---|---|---|
committer | Alex Deucher <alexander.deucher@amd.com> | 2020-06-11 16:05:32 -0400 |
commit | 9ec051bf4470ee20505c3c1bca9dc441944de4df (patch) | |
tree | 6cfbb7ed0489c3be6ba0dcb1fa227655a04cef61 /drivers/gpu/drm/amd/display/dc/dsc/rc_calc.h | |
parent | 790243d3bf78f9830a3b2ffbca1ed0f528295d48 (diff) |
drm/amd/display: Rework dsc to isolate FPU operations
When we want to use float point operation on Linux
we need to use within special kernel protection
(`kernel_fpu_{begin,end}()`.), otherwise the kernel
can clobber userspace FPU register state. For detecting
these issues we use a tool named objtool (with -Ffa
flags) to highlight the FPU problems, all warnings can
be summed up as follows:
./tools/objtool/objtool check -Ffa
drivers/gpu/drm/amd/display/dc/dml/dml_common_defs.o
[..] dc/dsc/rc_calc.o: warning: objtool: get_qp_set()+0x2f8:
FPU instruction outside of kernel_fpu_{begin,end}()
[..] dc/dsc/rc_calc.o: warning: objtool: dsc_roundf()+0x5:
FPU instruction outside of kernel_fpu_{begin,end}()
[..] dc/dsc/rc_calc.o: warning: objtool: dsc_ceil()+0x5:
FPU instruction outside of kernel_fpu_{begin,end}()
[..] dc/dsc/rc_calc.o: warning: objtool: get_ofs_set()+0x3eb:
FPU instruction outside of kernel_fpu_{begin,end}()
[..] dc/dsc/rc_calc.o: warning: objtool: calc_rc_params()+0x3c:
FPU instruction outside of kernel_fpu_{begin,end}()
[..] dc/dsc/dc_dsc.o: warning: objtool:
get_dsc_bandwidth_range.isra.0()+0x8d:
FPU instruction outside of kernel_fpu_{begin,end}()
[..] dc/dsc/dc_dsc.o: warning: objtool: setup_dsc_config()+0x2ef:
FPU instruction outside of kernel_fpu_{begin,end}()
[..] dc/dsc/rc_calc_dpi.o: warning: objtool:copy_pps_fields()+0xbb:
FPU instruction outside of kernel_fpu_{begin,end}()
[..] dc/dsc/rc_calc_dpi.o: warning: objtool:
dscc_compute_dsc_parameters()+0x7b:
FPU instruction outside of kernel_fpu_{begin,end}()
This commit fixes the above issues by rework DSC as described:
1. Isolate all FPU operations in a single file;
2. Use FPU flags only in the file that handles FPU operations;
3. Isolate all functions that require float point operation in static
functions;
4. Add a mid-layer function that does not use any float point operation,
and that could be safely invoked in other parts of the code.
5. Keep float point operation under DC_FP_{START/END} macro.
CC: Christian König <christian.koenig@amd.com>
CC: Alexander Deucher <Alexander.Deucher@amd.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Tony Cheng <tony.cheng@amd.com>
CC: Harry Wentland <hwentlan@amd.com>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Reviewed-by: Mikita Lipski <Mikita.Lipski@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Diffstat (limited to 'drivers/gpu/drm/amd/display/dc/dsc/rc_calc.h')
-rw-r--r-- | drivers/gpu/drm/amd/display/dc/dsc/rc_calc.h | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/gpu/drm/amd/display/dc/dsc/rc_calc.h b/drivers/gpu/drm/amd/display/dc/dsc/rc_calc.h index b6b1f09c2009..21723fa6561e 100644 --- a/drivers/gpu/drm/amd/display/dc/dsc/rc_calc.h +++ b/drivers/gpu/drm/amd/display/dc/dsc/rc_calc.h @@ -77,7 +77,10 @@ struct qp_entry { typedef struct qp_entry qp_table[]; -void calc_rc_params(struct rc_params *rc, enum colour_mode cm, enum bits_per_comp bpc, float bpp, int slice_width, int slice_height, int minor_version); +void calc_rc_params(struct rc_params *rc, const struct drm_dsc_config *pps); +u32 calc_dsc_bytes_per_pixel(const struct drm_dsc_config *pps); +u32 calc_dsc_bpp_x16(u32 stream_bandwidth_kbps, u32 pix_clk_100hz, + u32 bpp_increment_div); #endif |