Re: [PATCH v1] iommu/riscv: Support 32-bit register accesses
From: Andreas Schwab
Date: Mon Jun 15 2026 - 04:21:26 EST
On Jun 15 2026, Zhanpeng Zhang wrote:
> +config RISCV_IOMMU_32BIT_ACCESS
> + bool "Use 32-bit accesses for RISC-V IOMMU registers"
> + depends on RISCV_IOMMU
> + help
> + Say Y when the RISC-V IOMMU MMIO window cannot be accessed
> + using naturally aligned 64-bit loads and stores.
> +
> + When enabled, 64-bit IOMMU registers are accessed as paired
> + 32-bit MMIO operations. This option does not describe an RV32
> + kernel or a 32-bit IOMMU architecture.
What is the expected setting in a generic kernel?
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Andreas Schwab, SUSE Labs, schwab@xxxxxxx
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