raspberrypi inclusion
category: feature
bugzilla: 50432

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Both coherent_dma_mask and dma_mask act as constraints on allocations
and bounce buffer usage, so be sure to set dma_mask to the appropriate
value otherwise the effective mask could be incorrect.
Signed-off-by: NPhil Elwell <phil@raspberrypi.org>
Signed-off-by: NFang Yafen <yafen@iscas.ac.cn>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>