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iommu/mediatek: fix out-of-range warning with clang

PATCH Applied Arnd Bergmann 3 participants 3 messages Sep 27, 2021 – Sep 28, 2021

Subsystems (3)
Arm MediaTek IOMMU MediaTek IOMMU driver
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Arnd Bergmann

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PATCH 1/1 iommu/mediatek: fix out-of-range warning with clang

From: Arnd Bergmann <[email protected]>

clang-14 notices that a comparison is never true when CONFIG_PHYS_ADDR_T_64BIT is disabled:

drivers/iommu/mtk_iommu.c:553:34: error: result of comparison of constant 5368709120 with expression of type 'phys_addr_t' (aka 'unsigned int') is always false [-Werror,-Wtautological-constant-out-of-range-compare]

        if (dom->data->enable_4GB && pa >= MTK_IOMMU_4GB_MODE_REMAP_BASE)
                                     ~~ ^  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Add an explicit check for the type of the variable to skip the check and the warning in that case.

Fixes b4dad40e4f35 ("iommu/mediatek: Adjust the PA for the 4GB Mode")
Signed-off-by Arnd Bergmann <[email protected]>
---
 drivers/iommu/mtk_iommu.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
drivers/iommu/mtk_iommu.c +3 -1
index d837adfd1da5..25b834104790 100644
@@ -550,7 +550,9 @@ static phys_addr_t mtk_iommu_iova_to_phys(struct iommu_domain *domain,
 	phys_addr_t pa;
 
 	pa = dom->iop->iova_to_phys(dom->iop, iova);
-	if (dom->data->enable_4GB && pa >= MTK_IOMMU_4GB_MODE_REMAP_BASE)
+	if (IS_ENABLED(CONFIG_PHYS_ADDR_T_64BIT) &&
+	    dom->data->enable_4GB &&
+	    pa >= MTK_IOMMU_4GB_MODE_REMAP_BASE)
 		pa &= ~BIT_ULL(32);
 
 	return pa;
Signature · 1 line
2.29.2
maintainer Reviewed-by on v1 1/1
#1 lore raw
Quoted 12 lines · Arnd Bergmann

From: Arnd Bergmann <[email protected]>

clang-14 notices that a comparison is never true when CONFIG_PHYS_ADDR_T_64BIT is disabled:

drivers/iommu/mtk_iommu.c:553:34: error: result of comparison of constant 5368709120 with expression of type 'phys_addr_t' (aka 'unsigned int') is always false [-Werror,-Wtautological-constant-out- of-range-compare]

        if (dom->data->enable_4GB && pa >=
MTK_IOMMU_4GB_MODE_REMAP_BASE)
                                     ~~
Quoted 8 lines

^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Add an explicit check for the type of the variable to skip the check and the warning in that case.

Fixes b4dad40e4f35 ("iommu/mediatek: Adjust the PA for the 4GB

Mode")

Signed-off-by Arnd Bergmann <[email protected]>
Reviewed-by Yong Wu <[email protected]>

Thanks.