Re: [PATCH] SATA: OCTEON: support SATA on OCTEON platform

From: Rob Herring <robherring2@gmail.com>
To: David Daney <ddaney.cavm@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>,
	Aleksey Makarov <aleksey.makarov@auriga.com>,
	"linux-ide@vger.kernel.org" <linux-ide@vger.kernel.org>,
	"linux-mips@linux-mips.org" <linux-mips@linux-mips.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	David Daney <david.daney@cavium.com>,
	Anton Vorontsov <avorontsov@ru.mvista.com>,
	Vinita Gupta <vgupta@caviumnetworks.com>,
	Rob Herring <robh+dt@kernel.org>, Pawel Moll <Pawel.Moll@arm.com>,
	Ian Campbell <ijc+devicetree@hellion.org.uk>,
	Kumar Gala <galak@codeaurora.org>,
	Ralf Baechle <ralf@linux-mips.org>, Tejun Heo <tj@kernel.org>,
	Hans de Goede <hdegoede@redhat.com>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>
Subject: Re: [PATCH] SATA: OCTEON: support SATA on OCTEON platform
Date: Mon, 19 Jan 2015 14:30:22 -0600	[thread overview]
Message-ID: <CAL_JsqKq22K3kk7m09J1GZn9xXB+0tCUe75u3x+S3oWC0kyDcw@mail.gmail.com> (raw)
In-Reply-To: <54BD580C.6030701@gmail.com>

On Mon, Jan 19, 2015 at 1:16 PM, David Daney <ddaney.cavm@gmail.com> wrote:
> On 01/19/2015 07:43 AM, Mark Rutland wrote:
>>
>> On Mon, Jan 19, 2015 at 03:23:58PM +0000, Aleksey Makarov wrote:
>>>
>>> The OCTEON SATA controller is currently found on cn71XX devices.

[...]

>>> +
>>> +       /* Set a good dma_mask */
>>> +       pdev->dev.coherent_dma_mask = DMA_BIT_MASK(64);
>>> +       pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
>>
>>
>> I thought a dma-ranges property in the DT could be used to set up the
>> DMA mask appropriately?
>
>
> The DT contains no dma-ranges property, and we know a priori, that it should
> be 64-bits.

Neither this code nor dma-ranges should be necessary. The AHCI core
code will set the mask to 32 or 64 bits based on the AHCI Capabilities
register.

Rob