On 04/28/2013 10:28:14 PM, Kuo-Jung Su wrote:
2013/4/27 Scott Wood scottwood@freescale.com:
Shouldn't .eccpos depend on HWECC?
Actually it means nothing here, the ECC function is designed to be some kind of a blackbox to users (i.e softwares), the actual position of ECC codes are not documented in the datasheet, I have to dig it out from RTL which I do not have permission to access.
Maybe get rid of .eccpos altogether, and supply your own (much simpler) hwecc read/write_page functions -- similar to what fsl_elbc_nand, which also has transparent (but not hidden) ECC, does? This would also let you get rid of hwctl/calculate/correct.
Is it really all in one step, regardless of page size?
Theoretical, NO. It uses R-S or BCH for Forwarding Error Correction, which is selected at RTL level. Which means it actually 522 bytes per step at RS and 528 bytes per step at BCH.
However it's all blackbox to software, the FTNANDC021 simply supports only page read, so looks like everything is done at 1 step.
It would matter if you could detect correctable errors, but since you can't, it doesn't.
-Scott