Re: [PATCH v2 03/23] ata: sata_dwc_460ex: set dma_boundary to 0x1fff

From	Tejun Heo <tj@kernel.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH v2 03/23] ata: sata_dwc_460ex: set dma_boundary to 0x1fff
Date	2016-05-08 21:50 +0200
Message-ID	<rwCSd-4xB-5@gated-at.bofh.it> (permalink)
References	<rs7aj-4SP-21@gated-at.bofh.it> <rs7k1-4Yn-63@gated-at.bofh.it>
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On Tue, Apr 26, 2016 at 12:03:04PM +0300, Andy Shevchenko wrote:
> diff --git a/drivers/ata/sata_dwc_460ex.c b/drivers/ata/sata_dwc_460ex.c
> index 7f95389..aee8873 100644
> --- a/drivers/ata/sata_dwc_460ex.c
> +++ b/drivers/ata/sata_dwc_460ex.c
> @@ -1151,7 +1151,13 @@ static struct scsi_host_template sata_dwc_sht = {
>  	 */
>  	.sg_tablesize		= LIBATA_MAX_PRD,
>  	/* .can_queue		= ATA_MAX_QUEUE, */
> -	.dma_boundary		= ATA_DMA_BOUNDARY,
> +	/*
> +	 * Make sure a LLI block is not created that will span 8K max FIS
> +	 * boundary. If the block spans such a FIS boundary, there is a chance
> +	 * that a DMA burst will cross that boundary -- this results in an
> +	 * error in the host controller.
> +	 */
> +	.dma_boundary		= 0x1fff /* ATA_DMA_BOUNDARY */,

The host controller can't cross 8k boundary?  Is this for real?

-- 
tejun

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Re: [PATCH v2 03/23] ata: sata_dwc_460ex: set dma_boundary to 0x1fff Tejun Heo <tj@kernel.org> - 2016-05-08 21:50 +0200
  Re: [PATCH v2 03/23] ata: sata_dwc_460ex: set dma_boundary to 0x1fff Måns Rullgård <mans@mansr.com> - 2016-05-08 23:40 +0200

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