[U-Boot] [U-boot] [Patch v2 3/3] k2hk: change default nand ecc layout

[Ivan Khoronzhuk]

On 06/25/2014 02:25 AM, Scott Wood wrote:
> On Mon, 2014-06-23 at 18:26 +0300, Ivan Khoronzhuk wrote:
>> On 06/21/2014 02:40 AM, Scott Wood wrote:
>>> On Sat, 2014-06-21 at 02:28 +0300, Ivan Khoronzhuk wrote:
>>>> For keystyone k2hk board the default nand layout is different
>>>> from davinci. So swich ecc layout at init in board file.
>>>>
>>>> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk at ti.com>
>>>> ---
>>>>    board/ti/k2hk_evm/board.c | 11 +++++++++++
>>>>    1 file changed, 11 insertions(+)
>>>>
>>>> diff --git a/board/ti/k2hk_evm/board.c b/board/ti/k2hk_evm/board.c
>>>> index ef90f9d..baa6ab7 100644
>>>> --- a/board/ti/k2hk_evm/board.c
>>>> +++ b/board/ti/k2hk_evm/board.c
>>>> @@ -11,6 +11,7 @@
>>>>    #include <exports.h>
>>>>    #include <fdt_support.h>
>>>>    #include <libfdt.h>
>>>> +#include <nand.h>
>>>>    
>>>>    #include <asm/arch/hardware.h>
>>>>    #include <asm/arch/clock.h>
>>>> @@ -19,6 +20,7 @@
>>>>    #include <asm/arch/emac_defs.h>
>>>>    #include <asm/arch/psc_defs.h>
>>>>    #include <asm/ti-common/ti-aemif.h>
>>>> +#include <asm/ti-common/davinci_nand.h>
>>>>    
>>>>    DECLARE_GLOBAL_DATA_PTR;
>>>>    
>>>> @@ -147,6 +149,15 @@ int cpu_to_bus(u32 *ptr, u32 length)
>>>>    	return 0;
>>>>    }
>>>>    
>>>> +int board_nand_init(struct nand_chip *chip)
>>>> +{
>>>> +	davinci_nand_init(chip);
>>>> +	chip->ecc.layout =
>>>> +		board_nand_get_ecclayout(NAND_KEYSTONE_RBL_4BIT_LAYOUT);
>>>> +
>>>> +	return 0;
>>>> +}
>>> Shouldn't you be calling board_nand_set_ecclayout()?  How will oobavail
>>> get set?
>> There is no reason to set oobavail here, I suppose that's done while int
>> nand_scan_tail().
> But nand_scan_tail() has already run at this point.  oobavail would be
> set based on the wrong layout.

Where did you get.. I've checked it again. It was called after 
board_nand_init().

nand_init_chip
         -> board_nand_init
                 -> nand_scan
                         -> nand_scan_tail

>
>>> Is it really OK to start with the wrong ECC layout and switch later?
>> It can be used to boot from nand.
> That doesn't answer my question.

Seems It can be started with default ecc layout.
So I'm going to remove subj patch.

>
>>> Are you depending on lazy scanning of the BBT?
>> No, define CONFIG_SYS_NAND_USE_FLASH_BBT
> My point is, if the scanning of the BBT happens before you set the
> layout, it will be read using the wrong ECC layout.
>
>>> For that matter, you also seem to be assuming that markbad will never be
>>> called when the ECC is set to something other than what the BBT uses.
>>>
>>> -Scott
>>>
>>>
>> I suppose that only ECC layout is different.
> "only"?  That's a big deal.
>
> -Scott
>
>

If I correctly understand you, what if while we are writing data a new 
bad block is found?
Then we try to update BBT wich was written using a different layout....

Well probably I should rewrite BBT when layout is switched..
Will see if it can be done correctly.
Thanks.

-- 
Regards,
Ivan Khoronzhuk