[PATCH v2 2/4] iommu: dart: Add flag to override bypass support
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STALE1316d
SUPERSEDED: 1 (0M)
From: Sven Peter <hidden>
Date: 2023-02-28 20:22:02
Also in:
asahi, linux-devicetree, linux-iommu, lkml
Subsystem:
arm/apple machine support, iommu subsystem, the rest · Maintainers:
Sven Peter, Janne Grunau, Joerg Roedel, Will Deacon, Linus Torvalds
Revision v2 of 4 in this series; 1 review trailer.
Revisions (4)
- v1 [diff vs current]
- v2 current
- v3 [diff vs current]
- v4 [diff vs current]
The USB4 PCIe DARTs claim to support bypass but we never want to allow that on externally facing ports. Acked-by: Hector Martin <redacted> Signed-off-by: Sven Peter <redacted> --- drivers/iommu/apple-dart.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/iommu/apple-dart.c b/drivers/iommu/apple-dart.c
index 42666617803d..7d8b2b90cdb6 100644
--- a/drivers/iommu/apple-dart.c
+++ b/drivers/iommu/apple-dart.c@@ -182,6 +182,8 @@ struct apple_dart_hw { u64 ttbr_addr_field_shift; u64 ttbr_shift; int ttbr_count; + + bool disable_bypass; }; /*
@@ -1075,6 +1077,9 @@ static int apple_dart_probe(struct platform_device *pdev) dart->pgsize = 1 << FIELD_GET(DART_PARAMS1_PAGE_SHIFT, dart_params[0]); dart->supports_bypass = dart_params[1] & DART_PARAMS2_BYPASS_SUPPORT; + if (dart->hw->disable_bypass) + dart->supports_bypass = 0; + switch (dart->hw->type) { case DART_T8020: case DART_T6000:
--
2.25.1
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