[PATCH v9 1/3] MTD : add the common code for GPMI-NAND controller driver

Huang Shijie b32955 at freescale.com
Tue Aug 23 06:38:04 EDT 2011


Hi,
> On Tuesday, August 23, 2011 12:27:07 PM Huang Shijie wrote:
>> Hi,
>>
>>>>>> +}
>>>>>> +
>>>>>> +int common_nfc_set_geometry(struct gpmi_nand_data *this)
>>>>>> +{
>>>>>> +	struct bch_geometry *geo =&this->bch_geometry;
>>>>>> +	struct mtd_info *mtd =&this->mil.mtd;
>>>>>> +	unsigned int metadata_size;
>>>>>> +	unsigned int status_size;
>>>>>> +	unsigned int chunk_data_size_in_bits;
>>>>>> +	unsigned int chunk_ecc_size_in_bits;
>>>>>> +	unsigned int chunk_total_size_in_bits;
>>>>>> +	unsigned int block_mark_chunk_number;
>>>>>> +	unsigned int block_mark_chunk_bit_offset;
>>>>>> +	unsigned int block_mark_bit_offset;
>>>>>> +	int gf_len = 13;/* use GP13 by default */
>>>>>> +
>>>>>> +	/* We only support BCH now. */
>>>>>> +	geo->ecc_algorithm = "BCH";
>>>>>> +
>>>>>> +	/*
>>>>>> +	 * We always choose a metadata size of 10. Don't try to make sense
>>>>>> of +	 * it -- this is really only for historical compatibility.
>>>>>> +	 */
>>>>> Historical compat or you mean "the chip was designed this way, see
>>>>> datasheet section x.y.z"? ;-)
>>>> Just for historical compatibility.
>>>> it's better to keep it as now, there is no need to change it.
>>> I'm just trying to make sense of it ... from the docs, it seems like a
>>> chip design thing. So this is compat with STMP37xx and 36xx ? Or even
>>> something older and more obscure ?
>> The size of metadata can be changed, though it's set to 10 bytes now.
>>
>> But it can't be too large, because we have to save enough space for BCH.
> I saw the algo in the MX28 manual. Then just sum this up in the comment and it's
> good :)
>
ok, thanks :)

Huang Shijie
> Thanks!
>
> Cheers
>>
>> thanks
>> Huang Shijie





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