On 07.05.2024 11:05, Miquel Raynal wrote: > Hi Arseniy, > > avkrasnov@xxxxxxxxxxxxxxxxx wrote on Tue, 7 May 2024 10:35:51 +0300: > >> On 07.05.2024 10:27, Miquel Raynal wrote: >>> Hi Arseniy, >>> >>> avkrasnov@xxxxxxxxxxxxxxxxx wrote on Tue, 7 May 2024 09:53:06 +0300: >>> >>>> On 06.05.2024 16:48, Miquel Raynal wrote: >>>>> Hi Arseniy, >>>>> >>>>> avkrasnov@xxxxxxxxxxxxxxxxx wrote on Tue, 16 Apr 2024 11:51:00 +0300: >>>>> >>>>>> Boot ROM code on Meson requires that some pages on NAND must be written >>>>>> in special mode: "short" ECC mode where each block is 384 bytes and >>>>>> scrambling mode is on. >>>>> >>>>> Ok >>>>> >>>>>> Such pages located with the specified interval within specified offset. >>>>> >>>>> I'm sorry I don't get that sentence. >>>> >>>> Sorry, I mean this (let me draw :) ) : >>>> >>>> [ page 0 ][ page 1 ][ page 2 ][ page 3 ][ page 4 ][ page 5 ][ page 6 ][ page 7 ][ page 8 ][ page 9 ] >>>> >>>> For example, we have 10 pages starting from the beginning of the chip - this is "within specified offset", >>>> e.g. offset is 10. BootROM on axg needs that (for example) every third page must be written in "special" >>>> mode: scrambling is on and ECC is 384 bytes. Such pages are 0, 2, 4, 6, 8. E.g. "specified interval" will >>>> be 3. >>> >>> Shall be 2, no? >> >> yes, starting from 0 - then 2. e.g. >> if (!(page_num % 2)) >> boot ROM need this page >> >>> >>>> >>>> So: >>>> >>>> amlogic,boot-pages: 10 >>>> amlogic,boot-page-step: 3 >>> >>> Ok I get it. Thanks for the explanation. I don't really understand the >>> logic behind it though. Do you know why the bootROM would access only >>> one page over 2 or 3? Is there a default value? Is this configurable? >> >> No, boot rom source is closed, I don't have access to it. I get this logic >> from old version of vendor's uboot - in practice they use non 2 or 3, they >> use hardcoded 128 step value. And amlogic,boot-pages is 1024 > > Feels like they are trying to use only the first page of each block, no? > > That's very weird but I understand better. A little bit no, they use every 128 page in range [0, 1024] pages. E.g. there will be 8 such pages: 0 128 256 512 640 768 896 1024 They write some metadata about SoC to such pages. Thanks, Arseniy > > Thanks, > Miquèl
