Lines Matching refs:DMA
1 USB DMA
5 over how DMA may be used to perform I/O operations. The APIs are detailed
11 The big picture is that USB drivers can continue to ignore most DMA issues,
12 though they still must provide DMA-ready buffers (see
14 the 2.4 (and earlier) kernels, or they can now be DMA-aware.
16 DMA-aware usb drivers:
18 - New calls enable DMA-aware drivers, letting them allocate dma buffers and
25 - "usbcore" will map this DMA address, if a DMA-aware driver didn't do
29 - There's a new "generic DMA API", parts of which are usable by USB device
41 IOMMU to manage the DMA mappings. It can cost MUCH more to set up and
61 not using a streaming DMA mapping, so it's good for small transfers on
64 "streaming" DMA mappings.)
73 lines to prevent DMA conflicts.
75 - Devices on some EHCI controllers could handle DMA to/from high memory.
77 Unfortunately, the current Linux DMA infrastructure doesn't have a sane
84 high memory to "normal" DMA memory. If you can come up with a good way
91 Existing buffers aren't usable for DMA without first being mapped into the
92 DMA address space of the device. However, most buffers passed to your
93 driver can safely be used with such DMA mapping. (See the first section
94 of Documentation/core-api/dma-api-howto.rst, titled "What memory is DMA-able?")
108 When the USB controller doesn't support DMA, the ``usb_sg_init()`` would try