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

[Chin Liang See <clsee@altera.com>]

On Thu, 2015-12-03 at 01:10 +0100, Marek Vasut wrote:
> On Thursday, November 12, 2015 at 03:33:42 AM, Chin Liang See wrote:
> > On Thu, 2015-11-12 at 01:53 +0100, Marek Vasut wrote:
> > > On Thursday, November 12, 2015 at 01:49:09 AM, Chin Liang See
> > > wrote:
> > > > Hi Marek,
> > > > 
> > > > On Mon, 2015-11-09 at 17:02 +0100, Marek Vasut wrote:
> > > > > On Monday, November 09, 2015 at 04:46:54 PM, Stefan Roese
> > > > > wrote:
> > > > > > Hi Marek,
> > > > > 
> > > > > Hi!
> > > > > 
> > > > > > On 09.11.2015 14:49, Marek Vasut wrote:
> > > > > > 
> > > > > > <snip>
> > > > > > 
> > > > > > > > > > --- a/include/configs/socfpga_common.h
> > > > > > > > > > +++ b/include/configs/socfpga_common.h
> > > > > > > > > > @@ -73,7 +73,6 @@
> > > > > > > > > > 
> > > > > > > > > >    /*
> > > > > > > > > >    
> > > > > > > > > >     * Cache
> > > > > > > > > >     */
> > > > > > > > > > 
> > > > > > > > > > -#define CONFIG_SYS_ARM_CACHE_WRITEALLOC
> > > > > > > > > > 
> > > > > > > > > >    #define CONFIG_SYS_CACHELINE_SIZE 32
> > > > > > > > > >    #define CONFIG_SYS_L2_PL310
> > > > > > > > > >    #define CONFIG_SYS_PL310_BASE		
> SOCFPGA_MPUL2_ADDRESS
> > > > > > > > > 
> > > > > > > > > I hate to say it, but I am running into issues with
> > > > > > > > > this patch
> > > > > > > > > :-(
> > > > > > > > 
> > > > > > > > I'm sorry to hear this.
> > > > > > > > 
> > > > > > > > > I use a standard USB stick here and with this patch,
> > > > > > > > > I am
> > > > > > > > > getting the following failure (with enabled and
> > > > > > > > > disabled
> > > > > > > > > cache):
> > > > > > > > > 
> > > > > > > > > => usb reset
> > > > > > > > > resetting USB...
> > > > > > > > > USB0:   Core Release: 2.93a
> > > > > > > > > scanning bus 0 for devices... unable to get
> > > > > > > > > descriptor, error 0
> > > > > > > > > usb_new_device: Cannot read configuration, skipping
> > > > > > > > > device
> > > > > > > > > 058f:6387 1 USB Device(s) found
> > > > > > > > > 
> > > > > > > > >          scanning usb for storage devices... 0
> > > > > > > > > Storage
> > > > > > > > >          Device(s) found
> > > > > > > > > 
> > > > > > > > > => dcache off
> > > > > > > > > => usb reset
> > > > > > > > > resetting USB...
> > > > > > > > > USB0:   Core Release: 2.93a
> > > > > > > > > scanning bus 0 for devices... 2 USB Device(s) found
> > > > > > > > > 
> > > > > > > > >          scanning usb for storage devices... 1
> > > > > > > > > Storage
> > > > > > > > >          Device(s) found
> > > > > > > > > 
> > > > > > > > > If I revert this patch, my USB stick works as well.
> > > > > > > > > 
> > > > > > > > > I am also aware that Stefan mentions that without
> > > > > > > > > this patch,
> > > > > > > > > cache is not enabled at all. On the other hand, I
> > > > > > > > > cannot find
> > > > > > > > > any obviously faulty behavior in the dwc2 driver, it
> > > > > > > > > does
> > > > > > > > > flush_dcache_range()/invalidate_dcache_range() in the
> > > > > > > > > right
> > > > > > > > > places.
> > > > > > > > > 
> > > > > > > > > Any ideas please ?
> > > > > > > > 
> > > > > > > > Perhaps its a timing related issue? As the code is
> > > > > > > > executed
> > > > > > > > faster with cache enabled. Just an idea - perhaps there
> > > > > > > > is
> > > > > > > > still some ugly code that doesn't do proper timer based
> > > > > > > > loops /
> > > > > > > > delays.
> > > > > > > 
> > > > > > > I doubt that's not the case. If I disable cache just
> > > > > > > around the
> > > > > > > hcdma bit in the driver (disable before the
> > > > > > > flush_dcache_range()
> > > > > > > and enable after invalidate_dcache_range() in the
> > > > > > > driver), it
> > > > > > > still fails.
> > > > > > 
> > > > > > Did you check if this problem is perhaps also related to
> > > > > > Dinh's L2
> > > > > > cache patch:
> > > > > > 
> > > > > > 8d8e13e1 arm: socfpga: enable data/inst prefetch and shared
> > > > > > override in the L2
> > > > > > 
> > > > > > ?
> > > > > 
> > > > > Yes I did, but reverting this patch had no impact.
> > > > > 
> > > > > > I just noticed, that here the L2 cache gets disabled and is
> > > > > > not
> > > > > > enabled again in function v7_outer_cache_enable(). This
> > > > > > looks a
> > > > > > bit suspicious.
> > > > > > 
> > > > > > Dinh, did you perhaps miss to re-enable the L2 cache after
> > > > > > the
> > > > > > aux_ctrl register setup again?
> > > > > 
> > > > > I guess we should pester Dinh now :-)
> > > > 
> > > > I recompiled the latest source and it works for me.
> > > > Here is the printout message.
> > > > Wonder any modification against commit a55f28624e97e1e43ac?
> > > > 
> > > > 
> > > > U-Boot 2015.10-08073-ga55f286 (Nov 11 2015 - 23:19:06 +0800)
> > > > 
> > > > CPU:   Altera SoCFPGA Platform
> > > > FPGA:  Altera Cyclone V, SE/A6 or SX/C6 or ST/D6, version 0x0
> > > > BOOT:  SD/MMC External Transceiver (1.8V)
> > > > 
> > > >        Watchdog enabled
> > > > 
> > > > I2C:   ready
> > > > DRAM:  1 GiB
> > > > MMC:   SOCFPGA DWMMC: 0
> > > > *** Warning - bad CRC, using default environment
> > > > 
> > > > In:    serial
> > > > Out:   serial
> > > > Err:   serial
> > > > Model: Altera SOCFPGA Cyclone V SoC Development Kit
> > > > Net:
> > > > Error: ethernet at ff702000 address not set.
> > > > No ethernet found.
> > > > Hit any key to stop autoboot:  0
> > > > => dcache
> > > > Data (writethrough) Cache is ON
> > > > => icache
> > > > Instruction Cache is ON
> > > > => usb start
> > > > starting USB...
> > > > USB0:   Core Release: 2.93a
> > > > scanning bus 0 for devices... 2 USB Device(s) found
> > > > 
> > > >        scanning usb for storage devices... 1 Storage Device(s)
> > > > found
> > > > 
> > > > => usb info
> > > > 1: Hub,  USB Revision 1.10
> > > > 
> > > >  -  U-Boot Root Hub
> > > >  - Class: Hub
> > > >  - PacketSize: 8  Configurations: 1
> > > >  - Vendor: 0x0000  Product 0x0000 Version 0.0
> > > >  
> > > >    Configuration: 1
> > > >    - Interfaces: 1 Self Powered 0mA
> > > >    
> > > >      Interface: 0
> > > >      - Alternate Setting 0, Endpoints: 1
> > > >      - Class Hub
> > > >      - Endpoint 1 In Interrupt MaxPacket 2 Interval 255ms
> > > > 
> > > > 2: Mass Storage,  USB Revision 2.0
> > > > 
> > > >  - SanDisk  SDDR-113 000000009412
> > > >  - Class: (from Interface) Mass Storage
> > > >  - PacketSize: 64  Configurations: 1
> > > >  - Vendor: 0x0781  Product 0xa7c1 Version 148.18
> > > >  
> > > >    Configuration: 1
> > > >    - Interfaces: 1 Bus Powered 500mA
> > > >    
> > > >      Interface: 0
> > > >      - Alternate Setting 0, Endpoints: 2
> > > >      - Class Mass Storage, Transp. SCSI, Bulk only
> > > >      - Endpoint 1 In Bulk MaxPacket 512
> > > >      - Endpoint 2 Out Bulk MaxPacket 512
> > > 
> > > Yeah, that's because you're using high-quality USB sticks which
> > > leave
> > > skid marks on the USB port. Now try with some dirt cheap USB 2.0
> > > stick.
> > > 
> > > 058f:6387 Alcor Micro Corp. Flash Drive
> > > 
> > > The thing above is my absolute fav when it comes to testing
> > > corner cases:
> > > http://www.intenso.de/produkte.php?kategorie=23&&produkt=12557234
> > > 75
> > 
> > It takes some amount of time for digging out a USB 2.0 stick :)
> > But it still work for me as below.
> > Let me check out the code and see any clue.
> > 
> > 
> > 2: Mass Storage,  USB Revision 2.0
> >  -          USB DISK 2.0     0781076602A6
> >  - Class: (from Interface) Mass Storage
> >  - PacketSize: 64  Configurations: 1
> >  - Vendor: 0x13fe  Product 0x1e00 Version 1.16
> >    Configuration: 1
> >    - Interfaces: 1 Bus Powered 200mA
> >      Interface: 0
> >      - Alternate Setting 0, Endpoints: 2
> >      - Class Mass Storage, Transp. SCSI, Bulk only
> >      - Endpoint 1 In Bulk MaxPacket 512
> >      - Endpoint 2 Out Bulk MaxPacket 512
> 
> 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 :)

Thanks
Chin Liang