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* [PATCH] iommu: Add Kconfig help text for IOMMU_SVA
@ 2023-05-06 13:31 Jacob Pan
  2023-05-06 15:19 ` kernel test robot
                   ` (3 more replies)
  0 siblings, 4 replies; 16+ messages in thread
From: Jacob Pan @ 2023-05-06 13:31 UTC (permalink / raw)
  To: LKML, iommu, Jason Gunthorpe, Lu Baolu, Joerg Roedel,
	Jean-Philippe Brucker, Robin Murphy
  Cc: Will Deacon, Raj Ashok, Tian, Kevin, Yi Liu, Yu, Fenghua,
	torvalds, Jacob Pan

Shared Virtual Addressing (SVA) is not immediately intuitive to people
who work outside IOMMU subsystem, add some explanation to make it less
opaque.
Link: https://lore.kernel.org/lkml/ZE70doFi8X3KgfrV@ziepe.ca/t/#meaa938c91857665b376db59e16b532ba9d4ea013
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
---
 drivers/iommu/Kconfig | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index db98c3f86e8c..0f7181007dc1 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: GPL-2.0-only
+# PDX-License-Identifier: GPL-2.0-only
 # The IOVA library may also be used by non-IOMMU_API users
 config IOMMU_IOVA
 	tristate
@@ -155,7 +155,14 @@ config IOMMU_DMA
 
 # Shared Virtual Addressing
 config IOMMU_SVA
-	bool
+	bool "Shared Virtual Addressing"
+	help
+	  IOMMU and CPU share page tables for user processes thus DMA can use
+	  CPU virtual address. Under intel architecture, it is also called
+	  Shared Virtual Memory (SVM).
+	  With SVA, DMA requests are tagged with PCIe Process Address Space ID
+	  (PASID) or Substream ID (ARM SMMU term) with which page tables are
+	  associated.
 
 config FSL_PAMU
 	bool "Freescale IOMMU support"
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 16+ messages in thread

end of thread, other threads:[~2023-05-09 23:06 UTC | newest]

Thread overview: 16+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2023-05-06 13:31 [PATCH] iommu: Add Kconfig help text for IOMMU_SVA Jacob Pan
2023-05-06 15:19 ` kernel test robot
2023-05-06 15:39 ` kernel test robot
2023-05-06 15:39 ` kernel test robot
2023-05-06 15:43 ` Linus Torvalds
2023-05-06 22:07   ` Jacob Pan
2023-05-07 18:52     ` Linus Torvalds
2023-05-08 16:40       ` Jacob Pan
2023-05-08 16:42         ` Linus Torvalds
2023-05-08 16:55           ` Jason Gunthorpe
2023-05-08 17:17             ` Linus Torvalds
2023-05-08 20:21               ` Jacob Pan
2023-05-09  0:13                 ` Tian, Kevin
2023-05-09  1:55                 ` Baolu Lu
2023-05-09  0:10               ` Tian, Kevin
2023-05-09 23:06               ` Jason Gunthorpe

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