RE: [PATCH 03/11] spi: Add a driver for the Freescale/NXP QuadSPI controller

[Yogesh Narayan Gaur <yogeshnarayan.gaur@nxp.com>]

Hi Boris,

-----Original Message-----
From: Boris Brezillon [mailto:boris.brezillon@bootlin.com] 
Sent: Monday, June 11, 2018 3:46 PM
To: Yogesh Narayan Gaur <yogeshnarayan.gaur@nxp.com>
Cc: marek.vasut@gmail.com; Frieder Schrempf <frieder.schrempf@exceet.de>; linux-mtd@lists.infradead.org; linux-spi@vger.kernel.org; dwmw2@infradead.org; computersforpeace@gmail.com; richard@nod.at; miquel.raynal@bootlin.com; broonie@kernel.org; David Wolfe <david.wolfe@nxp.com>; Fabio Estevam <fabio.estevam@nxp.com>; Prabhakar Kushwaha <prabhakar.kushwaha@nxp.com>; Han Xu <han.xu@nxp.com>; linux-kernel@vger.kernel.org
Subject: Re: [PATCH 03/11] spi: Add a driver for the Freescale/NXP QuadSPI controller

On Mon, 11 Jun 2018 09:38:14 +0000
Yogesh Narayan Gaur <yogeshnarayan.gaur@nxp.com> wrote:

> > > Observation 3:
> > > As we can support JFFS2 filesystem on NOR flash, so we can expect JFFS2 commands should work fine on NOR flash.
> > > But with this driver change my mount command is not working.
> > > 
> > > In my target there are 2 flash slave devices connected, and I have given argument to create MTD partition like "mtdparts=20c0000.quadspi-1:5M(rcw),10M(test),46M(rootfs) " for 2nd flash.
> > > Below is output for /proc/mtd commands
> > >     root@ls1012ardb:~# cat /proc/mtd
> > >     dev:    size   erasesize  name
> > >     mtd0: 04000000 00040000 "20c0000.quadspi-0"   --> First 64MB flash
> > >     mtd1: 00500000 00040000 "rcw"                               --> Second 64 MB flash device, 3 MTD partition are created for it.
> > >     mtd2: 00a00000 00040000 "test"
> > >     mtd3: 02e00000 00040000 "rootfs"

When I do mtd1 + mtd2 + mtd3, I end up with 0x3d00000 instead of 0x4000000. Is that normal? Do you reserve a bit of space at the end or is it that rcw is not starting at 0?

I have given partition size n bootargs as mtdparts=20c0000.quadspi-1:5M(rcw),10M(test),46M(rootfs)
5 + 10 + 46 ==> 61M i.e. 0x3d00000.
I have just reserve the bit at the end, we can modify these settings also.

> > > 
> > >     root@ls1012ardb:~# mkdir /media/ram ; flash_eraseall /dev/mtd3
> > >     flash_eraseall has been replaced by `flash_erase <mtddev> 0 0`; please use it
> > >     Erasing 256 Kibyte @ 0 --  0 % complete [   18.299929] random: crng init done
> > >     Erasing 256 Kibyte @ 2dc0000 -- 100 % complete
> > >     root@ls1012ardb:~# mount -t jffs2 /dev/mtdblock3 /media/ram/
> > > 
> > > This command didn't finish successfully and there are lot of messages coming on console mentioning failure in jffs2_scan_eraseblock()
> > >     [  187.118677] jffs2: jffs2_scan_eraseblock(): Magic bitmask 
> > > 0x1985 not found at 0x013c0000: 0x2886 instead

Did you try to create a smaller partition? Maybe we have a problem when accessing addresses higher than X with the new driver (X to be determined).

Would try and update you.

--
Regards
Yogesh Gaur

> > >     [  187.128159] jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x013c0004: 0x7a3b instead
> > >     [  187.137641] jffs2: jffs2_scan_eraseblock(): Magic bitmask
> > > 0x1985 not found at 0x013c0008: 0xb10f instead
> > >