From: "R, Vignesh" <vigneshr@ti.com>
To: Marek Vasut <marex@denx.de>,
"linux-mtd@lists.infradead.org" <linux-mtd@lists.infradead.org>
Cc: Graham Moore <grmoore@opensource.altera.com>,
Alan Tull <atull@opensource.altera.com>,
Brian Norris <computersforpeace@gmail.com>,
David Woodhouse <dwmw2@infradead.org>,
Dinh Nguyen <dinguyen@opensource.altera.com>,
Yves Vandervennet <yvanderv@opensource.altera.com>,
"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>
Subject: Re: [PATCH V10 2/2] mtd: spi-nor: Add driver for Cadence Quad SPI Flash Controller.
Date: Thu, 14 Apr 2016 22:11:39 +0530 [thread overview]
Message-ID: <570FC843.9010403@ti.com> (raw)
In-Reply-To: <570E608C.1030901@denx.de>
On 04/13/2016 08:36 PM, Marek Vasut wrote:
> On 04/07/2016 06:55 AM, Vignesh R wrote:
>>
>>
>> On 04/07/2016 01:00 AM, Marek Vasut wrote:
>>> On 04/06/2016 06:55 PM, R, Vignesh wrote:
>>>> Hi Marek,
>>>
>>> Hi!
>>>
>>>> I encountered a issue with this driver while testing.
>>>
>>> Try with the attached patches, I am planning to use them for V11
>>> submission. I think you're hitting the problem with missing buslock.
>>>
>>
>> Thanks for the patches.
>> But I am pretty sure that's not the problem at my end, because I have
>> only one flash device on QSPI bus.
>>
>> The problem is cqspi_switch_cs() is called only once ie when JEDEC ID is
>> being read(during autodetect of chip), but at that instance,
>> nor->page_size and nor->mtd.erasesize are not yet initialized (They are
>> initialized only after JEDEC ID is looked up in the table and page_size
>> and erasesize are known).
>> Therefore if nor->page_size is printed during cqspi_switch_cs() then its
>> zero. But nor->page_size reports 256 when printed in cqspi_flash_setup()
>> after spi_nor_scan(). Therefore CQSPI_REG_SIZE register has to be
>> configured only after spi_nor struct is fully populated (i.e after
>> spi_nor_scan() has recognized the slave after JEDEC ID read).
>
> Got it and I have a patch for this. Nice find, thanks! It gave me 60%
> read performance boost on my machine :-)
>
Ah, hope I will see similar improvement at my end :)
> I am now caching the page_size, erasesize, addr_width values, so I can
> avoid reconfiguring the controller if there is no need for it, but
> reconfigure it if there is a need. The patch is attached, but it's quite
> big, so I also pushed a git branch with this driver for your convenience
> (based on linux-next, expect rebases):
>
> https://git.kernel.org/cgit/linux/kernel/git/marex/linux-2.6.git/log/?h=next/cadence-qspi
>
Ok, I will test this on my board sometime soon, thanks.
--
Regards
Vignesh
next prev parent reply other threads:[~2016-04-14 16:42 UTC|newest]
Thread overview: 40+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-11 4:34 [PATCH V8 1/2] mtd: spi-nor: Bindings for Cadence Quad SPI Flash Controller driver Marek Vasut
2016-01-11 4:34 ` [PATCH V10 2/2] mtd: spi-nor: Add driver for Cadence Quad SPI Flash Controller Marek Vasut
2016-01-11 16:09 ` Dinh Nguyen
2016-01-11 16:32 ` Marek Vasut
2016-01-12 4:41 ` Vignesh R
2016-01-12 13:49 ` Marek Vasut
2016-04-06 16:55 ` R, Vignesh
2016-04-06 19:30 ` Marek Vasut
2016-04-07 4:55 ` Vignesh R
2016-04-13 10:27 ` Marek Vasut
2016-04-13 15:06 ` Marek Vasut
2016-04-14 16:41 ` R, Vignesh [this message]
2016-04-14 17:46 ` Marek Vasut
2016-05-13 0:00 ` Trent Piepho
2016-05-13 0:24 ` Marek Vasut
2016-05-13 20:43 ` Trent Piepho
2016-05-25 23:08 ` Marek Vasut
2016-05-25 23:02 ` Marek Vasut
2016-01-11 16:06 ` [PATCH V8 1/2] mtd: spi-nor: Bindings for Cadence Quad SPI Flash Controller driver Dinh Nguyen
2016-01-11 16:32 ` Marek Vasut
2016-01-11 17:03 ` Dinh Nguyen
2016-01-11 17:27 ` Marek Vasut
2016-01-13 2:26 ` Rob Herring
2016-01-13 2:39 ` Marek Vasut
2016-02-01 21:03 ` Brian Norris
2016-02-01 21:13 ` Marek Vasut
2016-02-04 7:38 ` Vignesh R
2016-02-04 11:25 ` Marek Vasut
2016-02-04 17:04 ` Dinh Nguyen
2016-02-06 7:42 ` Marek Vasut
2016-02-04 17:30 ` R, Vignesh
2016-02-06 7:42 ` Marek Vasut
2016-02-08 11:19 ` Vignesh R
2016-02-08 15:27 ` Marek Vasut
2016-02-10 16:10 ` Graham Moore
2016-02-10 16:17 ` Marek Vasut
2016-03-10 20:55 ` Graham Moore
2016-03-10 21:10 ` Marek Vasut
2016-03-14 18:17 ` Graham Moore
2016-03-14 22:47 ` Marek Vasut
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