34 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			34 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
config DRM_RADEON_KMS
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	bool "Enable modesetting on radeon by default"
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	depends on DRM_RADEON
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	help
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	  Choose this option if you want kernel modesetting enabled by default,
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	  and you have a new enough userspace to support this. Running old
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	  userspaces with this enabled will cause pain.
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	  When kernel modesetting is enabled the IOCTL of radeon/drm
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	  driver are considered as invalid and an error message is printed
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	  in the log and they return failure.
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	  KMS enabled userspace will use new API to talk with the radeon/drm
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	  driver. The new API provide functions to create/destroy/share/mmap
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	  buffer object which are then managed by the kernel memory manager
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	  (here TTM). In order to submit command to the GPU the userspace
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	  provide a buffer holding the command stream, along this buffer
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	  userspace have to provide a list of buffer object used by the
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	  command stream. The kernel radeon driver will then place buffer
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	  in GPU accessible memory and will update command stream to reflect
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	  the position of the different buffers.
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	  The kernel will also perform security check on command stream
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	  provided by the user, we want to catch and forbid any illegal use
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	  of the GPU such as DMA into random system memory or into memory
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	  not owned by the process supplying the command stream. This part
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	  of the code is still incomplete and this why we propose that patch
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	  as a staging driver addition, future security might forbid current
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	  experimental userspace to run.
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	  This code support the following hardware : R1XX,R2XX,R3XX,R4XX,R5XX
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	  (radeon up to X1950). Works is underway to provide support for R6XX,
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	  R7XX and newer hardware (radeon from HD2XXX to HD4XXX).
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