From 06b3e35cc964d4735bd62d293b9d51f689545f97 Mon Sep 17 00:00:00 2001 From: "Suren A. Chilingaryan" Date: Sun, 17 Jul 2011 14:22:32 +0200 Subject: Handle correctly reference counting in the driver --- NOTES | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'NOTES') diff --git a/NOTES b/NOTES index 4efca52..3f1eadb 100644 --- a/NOTES +++ b/NOTES @@ -1,3 +1,12 @@ +Memory Addressing +================= + There is 3 types of addresses: virtual, physical, and bus. For DMA a bus + address is used. However, on x86 physical and bus addresses are the same (on + other architectures it is not guaranteed). Anyway, this assumption is still + used by xdma driver, it uses phiscal address for DMA access. I have ported + in the same way. Now, we need to provide additionaly bus-addresses in kmem + abstraction and use it in NWL DMA implementation. + DMA Access Synchronization ========================== - At driver level, few types of buffers are supported: -- cgit v1.2.3