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 Post subject: Intel HD Graphics: GTT Framebuffer Question
PostPosted: Mon Jan 06, 2020 2:06 pm 
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Hi,

Does any of you know if the framebuffer located at BAR #2 has to be mapped via the GTT in order for updates to be applied.
Right now I cannot get it to work, I've tried everything. Mode settings works perfectly but writes to the framebuffer are not being displayed.
Is it possible that the newer versions of the GPU chip require you to map the framebuffer before it can be used?

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 Post subject: Re: Intel HD Graphics: GTT Framebuffer Question
PostPosted: Tue Jan 07, 2020 8:50 am 
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The BIOS will configure a small part of the GTT for the VBE framebuffer (and/or its own use). If you want to use large amounts of VRAM, however, you have to modify the GTT.

Intel's documentation outlines several restrictions on how VRAM can be accessed, e.g., in some cases, you may only access it through the BAR and not by modifying physical RAM.

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