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[v6,03/15] swiotlb: Add DMA_RESTRICTED_POOL

Message ID 20210510095026.3477496-4-tientzu@chromium.org
State Not Applicable
Headers show
Series Restricted DMA | expand

Checks

Context Check Description
snowpatch_ozlabs/apply_patch success Successfully applied on branch powerpc/merge (fcc98c6d0289241dded10b74f8198fc4ecb22bd1)
snowpatch_ozlabs/checkpatch success total: 0 errors, 0 warnings, 0 checks, 20 lines checked
snowpatch_ozlabs/needsstable success Patch has no Fixes tags

Commit Message

Claire Chang May 10, 2021, 9:50 a.m. UTC
Add a new kconfig symbol, DMA_RESTRICTED_POOL, for restricted DMA pool.

Signed-off-by: Claire Chang <tientzu@chromium.org>
---
 kernel/dma/Kconfig | 14 ++++++++++++++
 1 file changed, 14 insertions(+)
diff mbox series

Patch

diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
index 77b405508743..3e961dc39634 100644
--- a/kernel/dma/Kconfig
+++ b/kernel/dma/Kconfig
@@ -80,6 +80,20 @@  config SWIOTLB
 	bool
 	select NEED_DMA_MAP_STATE
 
+config DMA_RESTRICTED_POOL
+	bool "DMA Restricted Pool"
+	depends on OF && OF_RESERVED_MEM
+	select SWIOTLB
+	help
+	  This enables support for restricted DMA pools which provide a level of
+	  DMA memory protection on systems with limited hardware protection
+	  capabilities, such as those lacking an IOMMU.
+
+	  For more information see
+	  <Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt>
+	  and <kernel/dma/swiotlb.c>.
+	  If unsure, say "n".
+
 #
 # Should be selected if we can mmap non-coherent mappings to userspace.
 # The only thing that is really required is a way to set an uncached bit