[PATCH 3/3] mtd/nand : workaround for Freescale FCM to support large-page Nand chip

Scott Wood scottwood at freescale.com
Tue Nov 29 08:49:33 EST 2011


On 11/28/2011 03:48 PM, Scott Wood wrote:
> On 11/23/2011 06:41 PM, b35362 at freescale.com wrote:
>> From: Liu Shuo <b35362 at freescale.com>
>>
>> Freescale FCM controller has a 2K size limitation of buffer RAM. In order
>> to support the Nand flash chip whose page size is larger than 2K bytes,
>> we read/write 2k data repeatedly by issuing FIR_OP_RB/FIR_OP_WB and save
>> them to a large buffer.
>>
>> Signed-off-by: Liu Shuo <b35362 at freescale.com>
>> Signed-off-by: Li Yang <leoli at freescale.com>
>> ---
>>  drivers/mtd/nand/fsl_elbc_nand.c |  211 +++++++++++++++++++++++++++++++++++---
>>  1 files changed, 194 insertions(+), 17 deletions(-)
>>
>> diff --git a/drivers/mtd/nand/fsl_elbc_nand.c b/drivers/mtd/nand/fsl_elbc_nand.c
>> index d634c5f..c96e714 100644
>> --- a/drivers/mtd/nand/fsl_elbc_nand.c
>> +++ b/drivers/mtd/nand/fsl_elbc_nand.c
>> @@ -55,7 +55,9 @@ struct fsl_elbc_mtd {
>>  	struct device *dev;
>>  	int bank;               /* Chip select bank number           */
>>  	u8 __iomem *vbase;      /* Chip select base virtual address  */
>> -	int page_size;          /* NAND page size (0=512, 1=2048)    */
>> +	int page_size;          /* NAND page size, the mutiple of 2048.
>> +				 * (0=512, 1=2048, 2=4096, 4=8192....)
>> +				 */
> 
> Again, please remove this.  It was sort-of reasonable when it was a
> boolean that selected between slightly different programming models.  It
> doesn't make sense as "mtd->writesize == 512 ? 0 : mtd->writesize / 512".

Sorry, I meant "mtd->writesize == 512 ? 0 : mtd->writesize / 2048".

-Scott



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