NOTE
Beginning with version 8.0.2 you can use WinDriver to allocate contiguous DMA buffers of more than 128KB on Linux. The following information is relevant for versions 8.01 and below of WinDriver.
By default you can allocate a contiguous DMA kernel buffer of no more than
128KB on Linux. (With regard to the possibility of performing Scatter/Gather
DMA on Linux — see Technical Document #47.)
It is possible to recompile the kernel to get larger sizes.
You can look for the bigphysarea patch, which enables DMA
allocation of buffers that are larger than 128KB.
You can also download the code for Linux kernels (the relevant
file is /usr/src/linux/mm/slab.c ; look for cache_sizes
struct) and study the code to understand how to do this, or join Linux-kernel
discussion groups on Usenet to get more information on this.
Please note, however, that we have not tested the aforementioned patch and
that we will not be able to provide support for any matters related to attempts
to increase the maximum DMA buffer allocation size.
If you do recompile the kernel to enable allocation of DMA buffers
that are larger than 128KB, you will also need to change the
implementation of LINUX_kmalloc() in
linux_wrappers.c. The current implementation returns
NULL if the requested allocation size is bigger than
128KB. If you use the bigphysarea patch, you will need to call
the relevant functions from the patch in LINUX_kmalloc().
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