• Robin Murphy's avatar
    iommu/io-pgtable-arm: Rationalise TTBRn handling · d1e5f26f
    Robin Murphy authored
    TTBR1 values have so far been redundant since no users implement any
    support for split address spaces. Crucially, though, one of the main
    reasons for wanting to do so is to be able to manage each half entirely
    independently, e.g. context-switching one set of mappings without
    disturbing the other. Thus it seems unlikely that tying two tables
    together in a single io_pgtable_cfg would ever be particularly desirable
    or useful.
    
    Streamline the configs to just a single conceptual TTBR value
    representing the allocated table. This paves the way for future users to
    support split address spaces by simply allocating a table and dealing
    with the detailed TTBRn logistics themselves.
    Tested-by: default avatarJordan Crouse <jcrouse@codeaurora.org>
    Signed-off-by: default avatarRobin Murphy <robin.murphy@arm.com>
    [will: Drop change to ttbr value]
    Signed-off-by: default avatarWill Deacon <will@kernel.org>
    d1e5f26f
msm_iommu.c 20.2 KB