Messages in this thread | | | Subject | Re: [PATCH v7 2/2] mtd: rawnand: meson: add support for Amlogic NAND flash controller | From | Liang Yang <> | Date | Tue, 11 Dec 2018 16:36:47 +0800 |
| |
Hi Miquel,
Thanks for your quickly reply.
On 2018/12/11 15:54, Miquel Raynal wrote: > Hi Liang, > > Liang Yang <liang.yang@amlogic.com> wrote on Tue, 11 Dec 2018 09:56:25 > +0800: > >> Hi Miquel, >> >> On 2018/12/10 22:50, Miquel Raynal wrote: >>> Hi Liang, >>> >>> Liang Yang <liang.yang@amlogic.com> wrote on Mon, 10 Dec 2018 20:12:39 >>> +0800: >>> >>>> On 2018/12/10 19:38, Boris Brezillon wrote: >>>>> On Mon, 10 Dec 2018 19:23:46 +0800 >>>>> Liang Yang <liang.yang@amlogic.com> wrote: >>>>> >>>>>> + mtd->ecc_stats.failed++; >>>>>>>> + continue; >>>>>>>> + } >>>>>>>> + mtd->ecc_stats.corrected += ECC_ERR_CNT(*info); >>>>>>>> + bitflips = max_t(u32, bitflips, ECC_ERR_CNT(*info)); >>>>>>>> + } >>>>>>> >>>>>>> Are you sure you handle correctly empty pages with bf? >>>>>>> >> if scramble is enable, i would say yes here. >>>>>> when scramble is disabled, i am considering how to use the helper >>>>>> nand_check_erased_ecc_chunk, but it seems that i can't get the ecc >>>>>> bytes which is caculated by ecc engine.by the way, nfc dma doesn't send >>>>>> out the ecc parity bytes. >>>>> >>>>> Even if the ECC engine is disabled? >>>>> >> No. >>>> When ECC engine is disabled, it can read the ecc parity bytes ; but there is another problem that i need to consider how code struct looks better when reading error with ecc opened and then try to raw read. >>>> Is there a good idea? >>> >>> When reading with ECC enabled, in case of uncorrectable error you >>> must re-read without ECC, then check if the page is empty or not with >>> the core helpers (nand_check_erased_*()). >>> >>> Is this what you meant? >>> >> yes. when uncorrectable ECC error, i need firstly read out the ECC bytes without ECC engine and then use the helper nand_check_erased_ecc_chunk to check if blank page. >> Of course, the precondition is without scrambler, or the bland page can be detected by meson NFC. > > A suppose you meant "blank page"? If yes, then you don't need the > helper to check for only-0xFF pages. If the controller tells you if the > page was blank, then just check for that bit. >
i think not. we need to return back the previous problem that how i can get the bitflips of one blank page. i think i need the helper.
> > Thanks, > Miquèl > > . >
| |