U-Boot OMAP GPMC ECC change

[Roger Quadros]

Hi Colin,

On 19/05/2023 02:19, Colin Foster wrote:
> Hi Roger,
> 
> I really appreciate the help!
> 
> On Thu, May 18, 2023 at 01:55:38PM +0300, Roger Quadros wrote:
>> Hi Colin,
>>
>> On 17/05/2023 22:39, Colin Foster wrote:
>>>
>>> I swapped in just U-Boot (not the SPL) with your patch, and everything
>>> seems to work!
>>>
>>> The issue of Uncorrectable ECC errors spam came from the SPL. Here's a
>>> snippet of the boot log with the "ecc" print as well as your patch:
>>>
>>
>> Thanks for the tests. Glad to hear issue is narrowed down to SPL.
> 
> I can "fix" the issue by just commenting out the "ECC uncorrectable
> errors" print :-)

lol

> 
>>
>>> U-Boot SPL 2023.04-00029-g26a9ce5314-dirty (May 17 2023 - 12:06:49 -0700)
>>> OMAP4460-GP ES1.1
>>> Trying to boot from NAND
>>> ecc: 2420106
>>> ecc: ebd922f6
>>> ecc: 333f844f
>>> ecc: ab812f72
>>
>> This is clearly the issue. They should all have been 0.
> 
> Interesting. With the "ecc" prints in U-Boot I also get some non-zero
> values:
> 
> ecc: 0
> ecc: 6bff997b
> ecc: 6bff997b
> ecc: 6bff997b
> 
> 
> Once I'm booted, I can use nanddump. It seems like everything is correct
> from the Linux side of things:
> 
> # nanddump -f mlo_dump /dev/mtd0
> ECC failed: 0
> ECC corrected: 0
> Number of bad blocks: 0
> Number of bbt blocks: 0
> Block size 131072, page size 2048, OOB size 64
> Dumping data starting at 0x00000000 and ending at 0x00020000...
> 
> # nanddump -f uboot1_dump /dev/mtd1
> ECC failed: 0
> ECC corrected: 0
> Number of bad blocks: 0
> Number of bbt blocks: 0
> Block size 131072, page size 2048, OOB size 64
> Dumping data starting at 0x00000000 and ending at 0x00180000...
> 
> # nanddump -f uboot2_dump /dev/mtd2
> ECC failed: 0
> ECC corrected: 0
> Number of bad blocks: 0
> Number of bbt blocks: 0
> Block size 131072, page size 2048, OOB size 64
> Dumping data starting at 0x00000000 and ending at 0x00180000...
> 
> # nanddump -f /dev/null /dev/mtd3
> ECC failed: 0
> ECC corrected: 6
> Number of bad blocks: 0
> Number of bbt blocks: 0
> Block size 131072, page size 2048, OOB size 64
> Dumping data starting at 0x00000000 and ending at 0x1fce0000...
> ECC: 1 corrected bitflip(s) at offset 0x0ab30800
> ECC: 1 corrected bitflip(s) at offset 0x0b008800
> ECC: 1 corrected bitflip(s) at offset 0x0deaa000
> ECC: 1 corrected bitflip(s) at offset 0x0ea5b000
> ECC: 1 corrected bitflip(s) at offset 0x0ecbc000
> ECC: 1 corrected bitflip(s) at offset 0x0ed61800
> 
> 
>> Can you please share your spl/u-boot.cfg?
> 
> Attached

Couple of questions there

1) CONFIG_MTDPARTS_DEFAULT "mtdparts=nandflash:0x20000(xload_raw),0x180000(u-boot),0x180000(u-boot-2),0x1fce0000(main)"
Is this correct and matches with what kernel sees?
I couldn't see the NAND partition table in the Kernel Device tree patch.

2)
#define CONFIG_SYS_NAND_U_BOOT_OFFS 0x20000
#define CONFIG_SYS_NAND_U_BOOT_OFFS_REDUND 0x1a0000

These don't seem to match what you have defined in MTDPARTS_DEFAULT.
Which one is correct?

How do you flash the MLO and u-boot image to NAND?

I tried on AM335x-EVM and it works fine both before and after commit 04fcd25873.

Once change I had to do was to increase the u-boot partition size
as u-boot image does not fit in original partition size.

-----boot log follows-----

U-Boot SPL 2023.01-rc4-00381-g04fcd25873-dirty (May 19 2023 - 15:10:15 +0300)
Trying to boot from NAND


U-Boot 2023.01-rc4-00381-g04fcd25873-dirty (May 19 2023 - 15:10:15 +0300)

CPU  : AM335X-GP rev 1.0
Model: TI AM335x EVM
DRAM:  512 MiB
Core:  156 devices, 17 uclasses, devicetree: separate
WDT:   Started wdt at 44e35000 with servicing every 1000ms (60s timeout)
NAND:  256 MiB
MMC:   OMAP SD/MMC: 0
Loading Environment from FAT... Unable to read "uboot.env" from mmc0:1... 
<ethaddr> not set. Validating first E-fuse MAC
Net:   eth2: ethernet at 4a100000, eth3: usb_ether
Hit any key to stop autoboot:  0 
=> 

=> mtd

device nand0 <nand.0>, # parts = 10
 #: name                size            offset          mask_flags
 0: NAND.SPL            0x00020000      0x00000000      0
 1: NAND.SPL.backup1    0x00020000      0x00020000      0
 2: NAND.SPL.backup2    0x00020000      0x00040000      0
 3: NAND.SPL.backup3    0x00020000      0x00060000      0
 4: NAND.u-boot-spl-os  0x00040000      0x00080000      0
 5: NAND.u-boot         0x00200000      0x000c0000      0
 6: NAND.u-boot-env     0x00020000      0x002c0000      0
 7: NAND.u-boot-env.backup10x00020000   0x002e0000      0
 8: NAND.kernel         0x00700000      0x00300000      0
 9: NAND.file-system    0x0f600000      0x00a00000      0


-- 
cheers,
-roger