diff options
| author | kib <kib@FreeBSD.org> | 2008-09-06 15:21:01 +0000 |
|---|---|---|
| committer | kib <kib@FreeBSD.org> | 2008-09-06 15:21:01 +0000 |
| commit | a38c80b72ef6466f089b0bb0a308e2460c8adf70 (patch) | |
| tree | b5eb66f89db523c1b63977d1899f271cc5d1546f /share | |
| parent | e4b90a03d05abcb1cb539ca3be7a7f39c6790f3b (diff) | |
| download | FreeBSD-src-a38c80b72ef6466f089b0bb0a308e2460c8adf70.zip FreeBSD-src-a38c80b72ef6466f089b0bb0a308e2460c8adf70.tar.gz | |
Document BUS_DMA_NOCACHE.
MFC after: 3 days
Diffstat (limited to 'share')
| -rw-r--r-- | share/man/man9/bus_dma.9 | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/share/man/man9/bus_dma.9 b/share/man/man9/bus_dma.9 index b2ab769..82eefc4 100644 --- a/share/man/man9/bus_dma.9 +++ b/share/man/man9/bus_dma.9 @@ -547,6 +547,13 @@ Are as follows: .It Dv BUS_DMA_NOWAIT The load should not be deferred in case of insufficient mapping resources, and instead should return immediately with an appropriate error. +.It Dv BUS_DMA_NOCACHE +The allocated memory will not be cached in the processor caches. +All memory accesses appear on the bus and are executed +without reordering. +Currently, the flag is implemented for i386 and amd64 architectures +only, where it results in the Strong Uncacheable +PAT to be set for the allocated virtual address range. .El .El .Pp |
