CHIPPro NAND issue with 4.12 rc1

[Angus Ainslie]

On 2017-05-20 09:14, Boris Brezillon wrote:
> Le Sat, 20 May 2017 08:49:04 -0600,
> Angus Ainslie <angus at akkea.ca> a écrit :
> 
>> Hi All,
>> 
>> I'm trying to boot a CHIPPro with the stock 4.12 rc1 kernel. If I make
>> no modifications to the sun5i-gr8-chip-pro.dtb the kernel boots but
>> can't find the root partition.
>> 
>> So I added the partitions to the dts file
>> 
>> diff --git a/arch/arm/boot/dts/sun5i-gr8-chip-pro.dts
>> b/arch/arm/boot/dts/sun5i-gr8-chip-pro.dts
>> index c55b11a..0e61e6b 100644
>> --- a/arch/arm/boot/dts/sun5i-gr8-chip-pro.dts
>> +++ b/arch/arm/boot/dts/sun5i-gr8-chip-pro.dts
>> @@ -146,6 +146,32 @@
>>                  reg = <0>;
>>                  allwinner,rb = <0>;
>>                  nand-ecc-mode = "hw";
>> +    nand-on-flash-bbt;
>> +
>> +    spl at 0 {
>> +      label = "SPL";
>> +      reg = /bits/ 64 <0x0 0x400000>;
>> +    };
>> +
>> +    spl-backup at 400000 {
>> +      label = "SPL.backup";
>> +      reg = /bits/ 64 <0x400000 0x400000>;
>> +    };
>> +
>> +    u-boot at 800000 {
>> +      label = "U-Boot";
>> +      reg = /bits/ 64 <0x800000 0x400000>;
>> +    };
>> +
>> +    env at c00000 {
>> +      label = "env";
>> +      reg = /bits/ 64 <0xc00000 0x400000>;
>> +    };
>> +
>> +    rootfs at 1000000 {
>> +      label = "rootfs";
>> +      reg = /bits/ 64 <0x1000000 0x1f000000>;
>> +    };
>>          };
>>   };
>> 
>> and now the kernel finds the partition but it times out trying to 
>> mount
>> it. It seems to be something in the dts files because if I use the
>> ntc-gr8-crumb.dts from the ntc 4.4.30 kernel then the system boots all
>> the way to userland.
> 
> Hm, that's weird. Just changing the dtb makes it work? Did you try to
> dump both dtbs and figure out what else changes?
> 

Yeah I thought it was weird too. I was thinking that maybe the pin muxes 
were getting changed and the rb net or the interrupt net was getting 
changed to a different function.

I did decompile to 2 dtb's and I couldn't find many differences. They 
were mostly around some pull ups and drive strength for some of the NAND 
and i2c pins. I tried adding those changes and it still didn't work so I 
went back to the minimal set of changes to reproduce the bug.

> Also, I wonder how the NAND is correctly detected without this patch
> [1].
> 


That patch seems to be in my 4.12-rc1 kernel, I have a definition for 
the TC58NVG2S0H.

>> 
>> [    7.130000] ubi0: scanning is finished
>> [    7.150000] ubi0: attached mtd4 (name "rootfs", size 496 MiB)
>> [    7.160000] ubi0: PEB size: 262144 bytes (256 KiB), LEB size: 
>> 258048
>> bytes
>> [    7.170000] ubi0: min./max. I/O unit sizes: 4096/4096, sub-page 
>> size
>> 1024
>> [    7.180000] ubi0: VID header offset: 1024 (aligned 1024), data
>> offset: 4096
>> [    7.190000] ubi0: good PEBs: 1977, bad PEBs: 7, corrupted PEBs: 0
>> [    7.200000] ubi0: user volume: 1, internal volumes: 1, max. volumes
>> count: 128
>> [    7.210000] ubi0: max/mean erase counter: 3/1, WL threshold: 4096,
>> image sequence number: 1444477407
>> [    7.220000] ubi0: available PEBs: 1, total reserved PEBs: 1976, 
>> PEBs
>> reserved for bad PEB handling: 33
> 
> UBI attach works...
> 
>> [    7.240000] hctosys: unable to open rtc device (rtc0)
>> [    7.250000] vcc3v0: disabling
>> [    7.250000] ALSA device list:
>> [    7.260000]   #0: sun4i-codec
>> [    7.260000] ubi0: background thread "ubi_bgt0d" started, PID 53
>> [    8.320000] sunxi_nand 1c03000.nand: wait interrupt timedout
>> [    9.320000] sunxi_nand 1c03000.nand: wait interrupt timedout
>> [   10.330000] sunxi_nand 1c03000.nand: wait for empty cmd FIFO 
>> timedout
>> [   11.340000] sunxi_nand 1c03000.nand: wait for empty cmd FIFO 
>> timedout
>> [   12.350000] sunxi_nand 1c03000.nand: wait for empty cmd FIFO 
>> timedout
>> [   13.360000] sunxi_nand 1c03000.nand: wait for empty cmd FIFO 
>> timedout
>> [   14.370000] sunxi_nand 1c03000.nand: wait for empty cmd FIFO 
>> timedout
>> [   14.380000] ubi0 warning: ubi_io_read: error -110 while reading 
>> 4096
>> bytes from PEB 1034:4096, read only 0 bytes, retry
> 
> And suddenly you get timeouts. That's really weird.


Is there anything I can do on this end to help debug ?


> 
> [1]https://github.com/NextThingCo/linux/commit/5ebc35ce1223ef14ace9479d5f97d0fce979e550