Krunoslav Kovac e752058b86 drm/amd/display: Optimize gamma calculations ... [Why&How] 1. Stack usage is pretty high as fixed31_32 struct is 8 bytes and we have functions with >30 vars on the stack. 2. Optimize gamma calculation by reducing number of calls to dc_fixpt_pow Our X points are divided into 32 regions wth 16 pts each. Each region is 2x the previous, meaning x[i] = 2*x[i-16] for i>=16. Using (2x)^gamma = 2^gamma * x^gamma, we can recursively compute powers of gamma, we just need first 16 pts to start it up. dc_fixpt_pow() is expensive, it computes x^y by doing exp(y*logx) Exp is done by Taylor series approximation, and log by Newton-like approximation that also uses exp internally. In short, it's significantly heavier than run-of-the-mill addition/subtraction/multiply. Signed-off-by: Krunoslav Kovac <Krunoslav.Kovac@amd.com> Reviewed-by: Anthony Koo <Anthony.Koo@amd.com> Acked-by: Aric Cyr <Aric.Cyr@amd.com> Acked-by: Leo Li <sunpeng.li@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>		2019-07-18 14:27:25 -05:00
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amdgpu_dm	drm/amd/display: add functionality to get pipe CRC source.	2019-07-18 14:18:09 -05:00
dc	drm/amd/display: Optimize gamma calculations	2019-07-18 14:27:25 -05:00
include	drm/amd/display:Use Pixel clock in 100Hz units for HDMI Audio wall clock DTO	2019-07-18 14:18:09 -05:00
modules	drm/amd/display: Optimize gamma calculations	2019-07-18 14:27:25 -05:00
Kconfig	drm/amd/display: Add drm_audio_component support to amdgpu_dm	2019-07-11 14:37:24 -05:00
Makefile	drm/amd/display: move clk_mgr files to right place	2019-05-31 10:39:31 -05:00
TODO	drm/amd/display: Convert remaining loggers off dc_logger	2018-07-13 14:48:42 -05:00