[U-Boot] [PATCH] arm: socfpga: Fix cache configuration

[Marek Vasut <marex@denx.de>]

On Monday, December 07, 2015 at 03:37:17 PM, Chin Liang See wrote:
> On Thu, 2015-12-03 at 17:22 +0100, Marek Vasut wrote:
> > On Thursday, December 03, 2015 at 05:11:23 PM, Chin Liang See wrote:
> > 
> > [...]
> > 
> > > > I have another board where I cannot use UBI on QSPI NOR and
> > > > reverting
> > > > this
> > > > patch magically fixes things.
> > > 
> > > I was testing this too as enabling the UBIFS on NOR and here are my
> > > output. Wonder how to simulate your errors as I can help to take a
> > > look?
> > > 
> > > 
> > > => icache
> > > Instruction Cache is ON
> > > => dcache
> > > Data (writethrough) Cache is ON
> > > => sf probe
> > > SF: Detected N25Q512 with page size 256 Bytes, erase size 4 KiB,
> > > total
> > > 64 MiB
> > > => mtdparts default
> > > => mtdparts
> > > 
> > > device nor0 <ff705000.spi>, # parts = 4
> > > #: name                size            offset          mask_flags
> > > 0: u-boot              0x00100000      0x00000000      0
> > > 1: uboot-env           0x00010000      0x00100000      0
> > > 2: rootfs              0x01000000      0x00110000      0
> > > 3: UBI                 0x02ef0000      0x01110000      0
> > > 
> > > active partition: nor0,0 - (u-boot) 0x00100000 @ 0x00000000
> > > 
> > > defaults:
> > > mtdids  : nor0=ff705000.spi
> > > mtdparts: mtdparts=ff705000.spi:1m(u-boot),64k(uboot
> > > -env),16m(rootfs),
> > > -(UBI)
> > > => sf erase u-boot 100000
> > > SF: 1048576 bytes @ 0x0 Erased: OK
> > > => ubi part u-boot
> > > ubi0: attaching mtd1
> > > ubi0: scanning is finished
> > > ubi0: empty MTD device detected
> > > ubi0: attached mtd1 (name "mtd=0", size 1 MiB)
> > > ubi0: PEB size: 4096 bytes (4 KiB), LEB size: 3968 bytes
> > > ubi0: min./max. I/O unit sizes: 1/256, sub-page size 1
> > > ubi0: VID header offset: 64 (aligned 64), data offset: 128
> > > ubi0: good PEBs: 256, bad PEBs: 0, corrupted PEBs: 0
> > > ubi0: user volume: 0, internal volumes: 1, max. volumes count: 23
> > > ubi0: max/mean erase counter: 1/0, WL threshold: 4096, image
> > > sequence
> > > number: 0
> > > ubi0: available PEBs: 252, total reserved PEBs: 4, PEBs reserved
> > > for
> > > bad PEB handling: 0
> > > => ubi createvol testvol c0000
> > > Creating dynamic volume testvol of size 786432
> > > => ubi write 0 testvol 100
> > > 256 bytes written to volume testvol
> > > => ubi read 200 testvol 100
> > > Read 256 bytes from volume testvol to 200
> > > => cmp.b 0 200 100
> > > Total of 256 byte(s) were the same
> > > => ubifsmount testvol
> > > Error reading superblock on volume 'testvol' errno=-22!
> > > ubifsmount - mount UBIFS volume
> > > 
> > > Usage:
> > > ubifsmount <volume-name>
> > > 
> > >     - mount 'volume-name' volume
> > > 
> > > => ubifsmount ubi0:testvol
> > > Error reading superblock on volume 'ubi0:testvol' errno=-22!
> > > ubifsmount - mount UBIFS volume
> > > 
> > > Usage:
> > > ubifsmount <volume-name>
> > > 
> > >     - mount 'volume-name' volume
> > > 
> > > In the mean time, I was not able to get ubifsmount works.
> > > Appreciate
> > > for any quick advise? Else will look into the code tomorrow as my
> > > bed
> > > is calling me :)
> > 
> > I usually write ubinized image into the "rootfs" partition (sf erase
> > and
> > then sf write) and then do 'ubi part rootfs' , which fails with error
> > 22
> > unless I revert this patch. If I dump the SPI NOR area after writing
> > the
> > data, I see that the last 2 bytes of some pages are corrupted.
> > 
> > I am using these parameters to generate my ~11MiB large ubinized
> > image:
> > MKFS_UBIFS_OPTS="-m 1 -e 65408 -c 200"
> > UBINIZE_OPTS="-m 1 -p 64KiB -s 1"
> > 
> > Here is the content of my ubinize.cfg:
> > [rootfs]
> > mode=ubi
> > image=root.ubifs
> > vol_id=0
> > vol_type=dynamic
> > vol_name=rootfs
> > vol_flags=autoresize
> 
> Thanks for the pointers.
> 
> I checked the source and enabled the debug message. Noticed my failure
> is due to small LEB and PEB size. It was set to 4k which is the sub
> -sector erase size of NOR flash. I suspect you didn't hit this as you
> generate ubinized image which is 64kB erase size.
> 
> I will continue to dig more. Need to ensure it works when user create
> UBI part in U-Boot on top of serial NOR flash (which is commonly 4kB
> erase size). Hopefully existing U-Boot already have source taking care
> this :)

I am tempted to revert this patch, since it breaks USB and UBI for me
on two different boards though.