svn commit: r334041 - head/share/man/man9

[Emmanuel Vadot]

Author: manu
Date: Tue May 22 13:45:24 2018
New Revision: 334041
URL: https://svnweb.freebsd.org/changeset/base/334041

Log:
  bus_dma(9): Correct arm64 BUS_DMA_COHERENT implementation note
  
  BUS_DMA_COHERENT isn't supported in bus_dmamap_create but bus_dma_tag_create.
  Document it properly.
  
  Submitted by:	andrew

Modified:
  head/share/man/man9/bus_dma.9

Modified: head/share/man/man9/bus_dma.9
==============================================================================
--- head/share/man/man9/bus_dma.9	Tue May 22 13:30:56 2018	(r334040)
+++ head/share/man/man9/bus_dma.9	Tue May 22 13:45:24 2018	(r334041)
@@ -446,6 +446,15 @@ allocated with
 Also, due to resource sharing with other tags, this flag does not guarantee
 that resources will be allocated or reserved exclusively for this tag.
 It should be treated only as a minor optimization.
+.It Dv BUS_DMA_COHERENT
+Indicate that the DMA engine and CPU are cache-coherent.
+Cached memory may be used to back allocations created by
+.Fn bus_dmamem_alloc .
+For
+.Fn bus_dma_tag_create ,
+the
+.Dv BUS_DMA_COHERENT
+flag is currently implemented on arm64.
 .El
 .It Fa lockfunc
 Optional lock manipulation function (may be
@@ -504,7 +513,7 @@ For
 .Fn bus_dmamap_create ,
 the
 .Dv BUS_DMA_COHERENT
-flag is currently implemented on arm64 and sparc64.
+flag is currently implemented on sparc64.
 .El
 .It Fa mapp
 Pointer to a