Re: [PATCH 07/17] 53c700: improve non-coherent DMA handling

From: James Bottomley <James.Bottomley@HansenPartnership.com>
To: Christoph Hellwig <hch@lst.de>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	 Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
	Joonyoung Shim <jy0922.shim@samsung.com>,
	Seung-Woo Kim <sw0312.kim@samsung.com>,
	Ben Skeggs <bskeggs@redhat.com>,
	Marek Szyprowski <m.szyprowski@samsung.com>,
	Tomasz Figa <tfiga@chromium.org>,
	Matt Porter <mporter@kernel.crashing.org>,
	iommu@lists.linux-foundation.org
Cc: alsa-devel@alsa-project.org, linux-samsung-soc@vger.kernel.org,
	linux-scsi@vger.kernel.org, linux-parisc@vger.kernel.org,
	linux-doc@vger.kernel.org, nouveau@lists.freedesktop.org,
	linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org,
	linux-mm@kvack.org, Stefan Richter <stefanr@s5r6.in-berlin.de>,
	netdev@vger.kernel.org, linux1394-devel@lists.sourceforge.net,
	linux-arm-kernel@lists.infradead.org,
	linux-media@vger.kernel.org
Subject: Re: [PATCH 07/17] 53c700: improve non-coherent DMA handling
Date: Mon, 14 Sep 2020 08:20:18 -0700	[thread overview]
Message-ID: <1600096818.4061.7.camel@HansenPartnership.com> (raw)
In-Reply-To: <20200914144433.1622958-8-hch@lst.de>

On Mon, 2020-09-14 at 16:44 +0200, Christoph Hellwig wrote:
> @@ -429,7 +430,7 @@ struct NCR_700_Host_Parameters {
>  	for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32));
> i++) { \
>  		__u32 val =
> bS_to_cpu((script)[A_##symbol##_used[i]]) + da; \
>  		(script)[A_##symbol##_used[i]] = bS_to_host(val); \
> -		dma_cache_sync((dev),
> &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
> +		dma_sync_to_dev((dev),
> &(script)[A_##symbol##_used[i]], 4); \
>  		DEBUG((" script, patching %s at %d to %pad\n", \
>  		       #symbol, A_##symbol##_used[i], &da)); \
>  	} \
> @@ -441,7 +442,7 @@ struct NCR_700_Host_Parameters {
>  	dma_addr_t da = value; \
>  	for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32));
> i++) { \
>  		(script)[A_##symbol##_used[i]] = bS_to_host(da); \
> -		dma_cache_sync((dev),
> &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
> +		dma_sync_to_dev((dev),
> &(script)[A_##symbol##_used[i]], 4); \
>  		DEBUG((" script, patching %s at %d to %pad\n", \
>  		       #symbol, A_##symbol##_used[i], &da)); \
>  	} \
> @@ -456,7 +457,7 @@ struct NCR_700_Host_Parameters {
>  		val &= 0xff00ffff; \
>  		val |= ((value) & 0xff) << 16; \
>  		(script)[A_##symbol##_used[i]] = bS_to_host(val); \
> -		dma_cache_sync((dev),
> &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
> +		dma_sync_to_dev((dev),
> &(script)[A_##symbol##_used[i]], 4); \
>  		DEBUG((" script, patching ID field %s at %d to
> 0x%x\n", \
>  		       #symbol, A_##symbol##_used[i], val)); \
>  	} \
> @@ -470,7 +471,7 @@ struct NCR_700_Host_Parameters {
>  		val &= 0xffff0000; \
>  		val |= ((value) & 0xffff); \
>  		(script)[A_##symbol##_used[i]] = bS_to_host(val); \
> -		dma_cache_sync((dev),
> &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
> +		dma_sync_to_dev((dev),
> &(script)[A_##symbol##_used[i]], 4); \
>  		DEBUG((" script, patching short field %s at %d to
> 0x%x\n", \
>  		       #symbol, A_##symbol##_used[i], val)); \
>  	} \

If you're going to change the macros from taking a device to taking a
hostdata structure then the descriptive argument name needs to change
... it can't be dev anymore.  I'm happy with it simply becoming 'h' if
hostdata is too long.

I already asked for this on the first go around:

https://lore.kernel.org/alsa-devel/1598971960.4238.5.camel@HansenPartnership.com/

James

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