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CHV has a programmable CSC unit on the pipe B sprites. Program the unit appropriately for BT.601 limited range YCbCr to full range RGB color conversion. This matches the programming we currently do for sprites on the other pipes and on other platforms. It seems the CSC only works when the input data is YCbCr. For RGB pixel formats it doesn't matter what we program into the CSC registers. Doesn't make much sense to me especially since the register names give the impression that RGB input data would also work. But that's how it behaves here. In the review discussions there's been some nice math to explain the values obtained here. First about the YCbCr->RGB matrix: "I had the RGB->YCbCr matrix, inverted it and the values came out. But they should match the wikipedia article. Also keep in mind that the coefficients are in .12 in fixed point format, hence we need a 1<<12 factor. So let's try it: Kb=.114 Kr=.299 (1<<12) * 255/219 ~= 4769 -(1<<12) * 255/112*(1-Kb)*Kb/(1-Kb-Kr) ~= -1605 -(1<<12) * 255/112*(1-Kr)*Kr/(1-Kb-Kr) ~= -3330 (1<<12) * 255/112*(1-Kr) ~= 6537 (1<<12) * 255/112*(1-Kb) ~= 8263 "Looks like the same values to me." And then about the limits used for clamping: "> where did you get these min/max? "The hardware apparently deals in 10bit values, so we need to multiply everything by 4 when we start with the 8bit min/max values. Y = [16:235] * 4 = [64:940] CbCr = ([16:240] - 128) * 4 = [-112:112] * 4 = [-448:448] "The -128 being the -0.5 bias that the hardware already applied before the data entered the CSC unit." Raw data is also supplied in 10bpc in the registers. Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by Rodrigo Vivi <rodrigo.vivi@intel.com> [danvet: Copypaste explanations&math from the review discussion.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> |
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| .. | ||
| armada | ||
| ast | ||
| bochs | ||
| bridge | ||
| cirrus | ||
| exynos | ||
| gma500 | ||
| i2c | ||
| i810 | ||
| i915 | ||
| mga | ||
| mgag200 | ||
| msm | ||
| nouveau | ||
| omapdrm | ||
| panel | ||
| qxl | ||
| r128 | ||
| radeon | ||
| rcar-du | ||
| savage | ||
| shmobile | ||
| sis | ||
| sti | ||
| tdfx | ||
| tegra | ||
| tilcdc | ||
| ttm | ||
| udl | ||
| via | ||
| vmwgfx | ||
| ati_pcigart.c | ||
| drm_agpsupport.c | ||
| drm_auth.c | ||
| drm_bufs.c | ||
| drm_cache.c | ||
| drm_context.c | ||
| drm_crtc_helper.c | ||
| drm_crtc_internal.h | ||
| drm_crtc.c | ||
| drm_debugfs.c | ||
| drm_dma.c | ||
| drm_dp_helper.c | ||
| drm_dp_mst_topology.c | ||
| drm_drv.c | ||
| drm_edid_load.c | ||
| drm_edid.c | ||
| drm_encoder_slave.c | ||
| drm_fb_cma_helper.c | ||
| drm_fb_helper.c | ||
| drm_flip_work.c | ||
| drm_fops.c | ||
| drm_gem_cma_helper.c | ||
| drm_gem.c | ||
| drm_global.c | ||
| drm_hashtab.c | ||
| drm_info.c | ||
| drm_internal.h | ||
| drm_ioc32.c | ||
| drm_ioctl.c | ||
| drm_irq.c | ||
| drm_legacy.h | ||
| drm_lock.c | ||
| drm_memory.c | ||
| drm_mipi_dsi.c | ||
| drm_mm.c | ||
| drm_modes.c | ||
| drm_modeset_lock.c | ||
| drm_of.c | ||
| drm_panel.c | ||
| drm_pci.c | ||
| drm_plane_helper.c | ||
| drm_platform.c | ||
| drm_prime.c | ||
| drm_probe_helper.c | ||
| drm_rect.c | ||
| drm_scatter.c | ||
| drm_sysfs.c | ||
| drm_trace_points.c | ||
| drm_trace.h | ||
| drm_vm.c | ||
| drm_vma_manager.c | ||
| Kconfig | ||
| Makefile | ||
| README.drm | ||
************************************************************
* For the very latest on DRI development, please see: *
* http://dri.freedesktop.org/ *
************************************************************
The Direct Rendering Manager (drm) is a device-independent kernel-level
device driver that provides support for the XFree86 Direct Rendering
Infrastructure (DRI).
The DRM supports the Direct Rendering Infrastructure (DRI) in four major
ways:
1. The DRM provides synchronized access to the graphics hardware via
the use of an optimized two-tiered lock.
2. The DRM enforces the DRI security policy for access to the graphics
hardware by only allowing authenticated X11 clients access to
restricted regions of memory.
3. The DRM provides a generic DMA engine, complete with multiple
queues and the ability to detect the need for an OpenGL context
switch.
4. The DRM is extensible via the use of small device-specific modules
that rely extensively on the API exported by the DRM module.
Documentation on the DRI is available from:
http://dri.freedesktop.org/wiki/Documentation
http://sourceforge.net/project/showfiles.php?group_id=387
http://dri.sourceforge.net/doc/
For specific information about kernel-level support, see:
The Direct Rendering Manager, Kernel Support for the Direct Rendering
Infrastructure
http://dri.sourceforge.net/doc/drm_low_level.html
Hardware Locking for the Direct Rendering Infrastructure
http://dri.sourceforge.net/doc/hardware_locking_low_level.html
A Security Analysis of the Direct Rendering Infrastructure
http://dri.sourceforge.net/doc/security_low_level.html