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Date:   Fri, 16 Dec 2022 01:49:38 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Serge Semin <fancer.lancer@gmail.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Serge Semin <Sergey.Semin@baikalelectronics.ru>,
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Subject: Re: [PATCH v7 23/25] PCI: dwc: Restore DMA-mask after MSI-data
 allocation
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References: <20221214235305.31744-1-Sergey.Semin@baikalelectronics.ru>
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On Fri, Dec 16, 2022 at 12:34:23PM +0300, Serge Semin wrote:
> What about instead of save/restore pattern I'll just change the
> dma_set_mask_and_coherent() method with the dma_set_coherent_mask()
> function call? It seems cleaner. Like this:

> Thus the platform-specific streaming DMA mask would be preserved.
> Since it's PCIe then having the streaming DMA-mask less than 32-bits
> wide is very much improbable. Moreover DW PCIe AXI-interface can be
> synthesize only with one out of two address bus widths: 32 and 64.

Where platform-specific means the dwc subdriver?  Yes, that seems
to work.  Alternatively have a flag that says which streaming mask
to set.