[MiNT] Allocation of video RAM

[Peter Persson <pep.fishmoose@gmail.com>]

Hi,

I'm not sure if I asked this before. I'm implementing a rudimentary driver for the SuperVidel. While driver isn't strictly necessary to use the card, it can greatly enhance the user experience (new blitter, higher video ram bandwidth etc).

My question is about video RAM (VRAM). Right now there is no functionality for this in the kernel, except Screalloc(). This means that the driver has to implement that stuff internally, which has several drawbacks. For example - if an application exits prematurely or doesn't do mfree() on allocated VRAM, the memory won't be freed. Furthermore, there will be no memory protection for this additional class of RAM if it isn't implemented in the kernel.

How difficult would it be to implement another class of RAM? Is it even feasible? And if it is - would it make sense to expand Mxalloc() to handle this new class of RAM, or would it be better to implement yet another system call for this?

best regards

-- PeP