Navigation: Linux Kernel Driver DataBase - web LKDDB: Main index - A index

CONFIG_ARM_DMA_IOMMU_ALIGNMENT: Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers

General informations

The Linux kernel configuration item CONFIG_ARM_DMA_IOMMU_ALIGNMENT:

Help text

DMA mapping framework by default aligns all buffers to the smallest PAGE_SIZE order which is greater than or equal to the requested buffer size. This works well for buffers up to a few hundreds kilobytes, but for larger buffers it just a waste of address space. Drivers which has relatively small addressing window (like 64Mib) might run out of virtual space with just a few allocations.

With this parameter you can specify the maximum PAGE_SIZE order for DMA IOMMU buffers. Larger buffers will be aligned only to this specified order. The order is expressed as a power of two multiplied by the PAGE_SIZE.



Raw data from LKDDb:


This page is automaticly generated with free (libre, open) software lkddb(see lkddb-sources).

The data is retrived from:

Automatic links from Google (and ads)

Custom Search

Popular queries:

Navigation: Linux Kernel Driver DataBase - web LKDDB: main index - A index

Automatically generated (in year 2017) with in lkddb-sources.