[PATCH 2/8] iommu/io-pgtable-arm: Support non-coherent stage-2 page tables

Will Deacon will at kernel.org
Fri Jan 10 07:28:46 PST 2020


Commit 9e6ea59f3ff3 ("iommu/io-pgtable: Support non-coherent page tables")
added support for non-coherent page-table walks to the Arm IOMMU page-table
backends. Unfortunately, it left the stage-2 allocator unchanged, so let's
hook that up in the same way.

Cc: Bjorn Andersson <bjorn.andersson at linaro.org>
Cc: Robin Murphy <robin.murphy at arm.com>
Signed-off-by: Will Deacon <will at kernel.org>
---
 drivers/iommu/io-pgtable-arm.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index 7b422b9fe05b..ab440b52a5f4 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -910,10 +910,16 @@ arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
 	}
 
 	/* VTCR */
-	reg = ARM_64_LPAE_S2_TCR_RES1 |
-	     (ARM_LPAE_TCR_SH_IS << ARM_LPAE_TCR_SH0_SHIFT) |
-	     (ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_IRGN0_SHIFT) |
-	     (ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_ORGN0_SHIFT);
+	reg = ARM_64_LPAE_S2_TCR_RES1;
+	if (cfg->coherent_walk) {
+		reg |= (ARM_LPAE_TCR_SH_IS << ARM_LPAE_TCR_SH0_SHIFT) |
+		       (ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_IRGN0_SHIFT) |
+		       (ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_ORGN0_SHIFT);
+	} else {
+		reg |= (ARM_LPAE_TCR_SH_OS << ARM_LPAE_TCR_SH0_SHIFT) |
+		       (ARM_LPAE_TCR_RGN_NC << ARM_LPAE_TCR_IRGN0_SHIFT) |
+		       (ARM_LPAE_TCR_RGN_NC << ARM_LPAE_TCR_ORGN0_SHIFT);
+	}
 
 	sl = data->start_level;
 
-- 
2.25.0.rc1.283.g88dfdc4193-goog




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