Re: [PATCH v4 08/12] device core: Introduce multiple dma pfn offsets

From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Jim Quinlan <james.quinlan@broadcom.com>
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Subject: Re: [PATCH v4 08/12] device core: Introduce multiple dma pfn offsets
Date: Sun, 7 Jun 2020 19:49:50 +0300	[thread overview]
Message-ID: <20200607164950.GX2428291@smile.fi.intel.com> (raw)
In-Reply-To: <20200605212706.7361-9-james.quinlan@broadcom.com>

On Fri, Jun 05, 2020 at 05:26:48PM -0400, Jim Quinlan wrote:
> The new field in struct device 'dma_pfn_offset_map' is used to facilitate
> the use of single or multiple pfn offsets between cpu addrs and dma addrs.
> It subsumes the role of dev->dma_pfn_offset -- a uniform offset.
> 
> The function of_dma_get_range() has been modified to take two additional
> arguments: the "map", which is an array that holds the information
> regarding the pfn offset regions, and map_size, which is the size in bytes
> of the map array.
> 
> of_dma_configure() is the typical manner to set pfn offsets but there are a
> number of ad hoc assignments to dev->dma_pfn_offset in the kernel driver
> code.  These cases now invoke the function
> dma_attach_uniform_pfn_offset(dev, pfn_offset).

...

> +		int ret = dma_attach_uniform_pfn_offset
> +				(dev, keystone_dma_pfn_offset);

It's strange indentation. Have you configured your editor correctly?
Seems to me as fit on one line.

> +		dev_err(dev, "set dma_pfn_offset%08lx%s\n",
> +			dev->dma_pfn_offset, ret ? " failed" : "");

...

> +	*map_size = (num_ranges + 1) * sizeof(**map);
> +	r = kzalloc(*map_size, GFP_KERNEL);

kcalloc()

> +	if (!r)
> +		return -ENOMEM;

...

> +		r->pfn_offset = PFN_DOWN(range.cpu_addr)
> +			- PFN_DOWN(range.bus_addr);

Ditto (indentation).

...

> +		unsigned long dma_pfn_offset
> +			= dma_pfn_offset_from_phys_addr(dev, paddr);

Ditto.

...

> +		unsigned long dma_pfn_offset
> +			= dma_pfn_offset_from_dma_addr(dev, dev_addr);

Ditto.

Check entire your series for a such, please!

-- 
With Best Regards,
Andy Shevchenko

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