Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH v9 6/9] i3c: master: Add driver for Cadence IP
To:     Boris Brezillon <boris.brezillon@bootlin.com>
CC:     Wolfram Sang <wsa@the-dreams.de>, <linux-i2c@vger.kernel.org>,
        Jonathan Corbet <corbet@lwn.net>, <linux-doc@vger.kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Arnd Bergmann <arnd@arndb.de>,
        Przemyslaw Sroka <psroka@cadence.com>,
        Arkadiusz Golec <agolec@cadence.com>,
        Alan Douglas <adouglas@cadence.com>,
        Bartosz Folta <bfolta@cadence.com>,
        Damian Kos <dkos@cadence.com>,
        Alicja Jurasik-Urbaniak <alicja@cadence.com>,
        Cyprian Wronka <cwronka@cadence.com>,
        Suresh Punnoose <sureshp@cadence.com>,
        Rafal Ciepiela <rafalc@cadence.com>,
        Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
        Nishanth Menon <nm@ti.com>, Rob Herring <robh+dt@kernel.org>,
        Pawel Moll <pawel.moll@arm.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Ian Campbell <ijc+devicetree@hellion.org.uk>,
        Kumar Gala <galak@codeaurora.org>,
        <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        Vitor Soares <Vitor.Soares@synopsys.com>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Linus Walleij <linus.walleij@linaro.org>,
        Xiang Lin <Xiang.Lin@synaptics.com>,
        <linux-gpio@vger.kernel.org>, Sekhar Nori <nsekhar@ti.com>,
        Przemyslaw Gaj <pgaj@cadence.com>,
        Peter Rosin <peda@axentia.se>,
        Mike Shettel <mshettel@codeaurora.org>,
        Stephen Boyd <swboyd@chromium.org>,
        Joe Perches <joe@perches.com>
References: <20181022133404.2061-1-boris.brezillon@bootlin.com>
 <20181022133404.2061-7-boris.brezillon@bootlin.com>
 <20181024202048.7e3534f7@bbrezillon>
 <99a506e3-d9d5-0d3e-26e1-031447c14857@ti.com>
 <20181024230432.66dd71df@bbrezillon>
From:   Grygorii Strashko <grygorii.strashko@ti.com>
Message-ID: <380d73a8-2e54-3cee-2fdd-c6e891df93f7@ti.com>
Date:   Wed, 24 Oct 2018 17:43:00 -0500
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101
 Thunderbird/60.2.1
MIME-Version: 1.0
In-Reply-To: <20181024230432.66dd71df@bbrezillon>
Content-Type: text/plain; charset="utf-8"; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk


On 10/24/18 4:04 PM, Boris Brezillon wrote:
> On Wed, 24 Oct 2018 15:25:17 -0500
> Grygorii Strashko <grygorii.strashko@ti.com> wrote:
> 
>> On 10/24/18 1:20 PM, Boris Brezillon wrote:
>>> Hi Arnd,
>>>
>>> On Mon, 22 Oct 2018 15:34:01 +0200
>>> Boris Brezillon <boris.brezillon@bootlin.com> wrote:
>>>
>>>    
>>>> +
>>>> +static void cdns_i3c_master_rd_from_rx_fifo(struct cdns_i3c_master *master,
>>>> +					    u8 *bytes, int nbytes)
>>>> +{
>>>> +	readsl(master->regs + RX_FIFO, bytes, nbytes / 4);
>>>
>>> Vitor reported a problem with readsl(): this function expects the 2nd
>>> argument to be aligned on 32-bit, which is not guaranteed here. Unless
>>> you see a better solution, I'll switch back to a loop doing:
>>>
>>> 	for (i = 0; i < nbytes; i += 4) {
>>> 		u32 tmp = __raw_readl(...);
>>
>> Pls, do not use __raw io.
> 
> Except this is exactly what I want here, unless you have a
> replacement for "readl() without a mem-barrier and without endianness
> conversion"
> 

Not sure why endianness is the problem. readl_relaxed?
Sry, I've missed that this is part of the driver not i3c core,
so minor/ignore.

-- 
regards,
-grygorii