Re: [PATCH v5] spi: spi-ti-qspi: Add DMA support for QSPI mmap read

From	Vignesh R <vigneshr@ti.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v5] spi: spi-ti-qspi: Add DMA support for QSPI mmap read
Date	2016-08-17 07:20 +0200
Message-ID	<s71qG-4Z2-13@gated-at.bofh.it> (permalink)
References	<s4d4Z-6KH-7@gated-at.bofh.it> <s4dy2-6VH-37@gated-at.bofh.it> <s4eNr-7FJ-9@gated-at.bofh.it> <s6RAZ-6EN-3@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Wednesday 17 August 2016 12:12 AM, Mark Brown wrote:
> On Tue, Aug 09, 2016 at 06:20:01PM +0530, Vignesh R wrote:
>>
>>
> 
>> According to this thread[1], converting virtual address
>> pointer into scatterlist which is then DMA mapped is unsafe on systems
>> with certain cache architecture. Hence, I added code to handle kmap
>> buffers inside the driver rather than updating generic spi-core code.
> 
> That's saying that things that aren't covered aren't DMAable safely at
> all which is a more general issue...
> 
>> If its okay to update the spi_map_buf() to handle kmap buffers as above
>> then I can submit the patch accordingly.
> 
> Yes, the whole point is that this is all in generic code so drivers
> don't need to worry about it.

Ok, I will send another version updating spi_map_buf() to handle kmap
buffers. Thanks!

-- 
Regards
Vignesh

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Re: [PATCH v5] spi: spi-ti-qspi: Add DMA support for QSPI mmap read Mark Brown <broonie@kernel.org> - 2016-08-16 20:50 +0200
  Re: [PATCH v5] spi: spi-ti-qspi: Add DMA support for QSPI mmap read Vignesh R <vigneshr@ti.com> - 2016-08-17 07:20 +0200

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