From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1754146AbbCECwx (ORCPT <rfc822;w@1wt.eu>);
	Wed, 4 Mar 2015 21:52:53 -0500
Received: from mail1.windriver.com ([147.11.146.13]:35436 "EHLO
	mail1.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1753924AbbCECwv (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Wed, 4 Mar 2015 21:52:51 -0500
Message-ID: <54F7C4F5.1040204@windriver.com>
Date: Thu, 5 Mar 2015 10:52:37 +0800
From: yjin <yanjiang.jin@windriver.com>
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0
MIME-Version: 1.0
To: Kim Phillips <kim.phillips@freescale.com>
CC: <horia.geanta@freescale.com>, <herbert@gondor.apana.org.au>,
        <davem@davemloft.net>, <ruchika.gupta@freescale.com>,
        <cristian.stoica@freescale.com>, <NiteshNarayanLal@freescale.com>,
        <linux-crypto@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <jinyanjiang@gmail.com>
Subject: Re: [PATCH 2/3] crypto: caam_rng: fix rng_unmap_ctx's DMA_UNMAP size
 problem
References: <1425365453-19358-1-git-send-email-yanjiang.jin@windriver.com>	<1425365453-19358-3-git-send-email-yanjiang.jin@windriver.com>	<20150303133120.6706da49d0f7188a8213fe36@freescale.com>	<54F69922.6080404@windriver.com> <20150304123623.324ab9594f04dd95c587b628@freescale.com>
In-Reply-To: <20150304123623.324ab9594f04dd95c587b628@freescale.com>
Content-Type: text/plain; charset="UTF-8"; format=flowed
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org


On 2015年03月05日 02:36, Kim Phillips wrote:
> On Wed, 4 Mar 2015 13:33:22 +0800
> yjin <yanjiang.jin@windriver.com> wrote:
>
>> On 2015年03月04日 03:31, Kim Phillips wrote:
>>> On Tue, 3 Mar 2015 14:50:52 +0800
>>> <yanjiang.jin@windriver.com> wrote:
>>>
>>>> -		dma_unmap_single(jrdev, ctx->sh_desc_dma, DESC_RNG_LEN,
>>>> -				 DMA_TO_DEVICE);
>>>> +		dma_unmap_single(jrdev, ctx->sh_desc_dma,
>>>> +				desc_bytes(ctx->sh_desc), DMA_TO_DEVICE);
>>> alignment: the 'd' in desc_bytes should fall directly under the 'j'
>>> in jrdev.
>>>
>>> Also, DESC_RNG_LEN should be corrected to (4 * CAAM_CMD_SZ).
>> Hi Kim,
>>
>> I can't find the obvious limitation for the RNG descriptor length in
>> Freescale documents, could you point out it?
> ?  rng_create_sh_desc() creates a fixed descriptor of exactly 4
> command-lengths.

Hi Kim,

Do you mean that the code itself limits the descriptor length? Not a 
hardware limitation.
If so, I prefer to dma_unmap with desc_bytes(ctx->sh_desc) as my 
previous patch, and correct DESC_RNG_LEN to (4 * CAAM_CMD_SZ).

Thanks!
Yanjiang

>
> Kim