flash_rom start and size

[Li-Ta Lo]

On Wed, 2004-04-21 at 11:03, YhLu wrote:
> In the PMC pm49fl004, You got eight 64K size blocks.
> 
> You can erase the individual block and write that block only.
> 
> Regards
> 
> YH
> 

The problem is the block size is different for different
flash parts. It requires a lot of code to handle this
difference. It is the reason why MTD got so big.

Ollie

> -----邮件原件-----
> 发件人: Li-Ta Lo [mailto:ollie at lanl.gov] 
> 发送时间: 2004年4月21日 9:49
> 收件人: YhLu
> 抄送: LinuxBIOS
> 主题: Re: 答复: flash_rom start and size
> 
> On Wed, 2004-04-21 at 10:40, YhLu wrote:
> > For example, 
> > 1. I only want to let end user to flash normal part [0-384k), and don't
> let
> > him touch fallback part [384k, 512k).
> 
> there is no way you can really lock the flash.
> 
> > 2. or I only want to update the payload image in the beginning, [0,64k). 
> > 
> 
> you need some kind of flash translation layer to accomplish this. You
> need to back up some part of the erase block you want reserve , erase
> the block and write with updated and reserved data.
> 
> You probably need MTD.
> 
> Ollie
>  
> > Regards
> > 
> > Yinghai Lu
> > -----邮件原件-----
> > 发件人: Li-Ta Lo [mailto:ollie at lanl.gov] 
> > 发送时间: 2004年4月21日 9:09
> > 收件人: YhLu
> > 抄送: LinuxBIOS
> > 主题: Re: flash_rom start and size
> > 
> > On Tue, 2004-04-20 at 20:06, YhLu wrote:
> > > Ollie or David,
> > > 
> > > Can you modify the flash_rom to take start and size command line?
> > > 
> > > I mean 
> > > 
> > > Flash_rom -start=0k -size=384k xxxx.rom
> > > 
> > > And xxxx.rom only to be 384k.
> > > 
> > 
> > Why do you want to do this ? You should prepare the image
> > the same size as your flash chip.
> > 
> > There are techinical difficulty doing this. Most flash
> > parts are block/sector erase and byte program. There is
> > no general way to start from an abitrary address to any
> > size.
> > 
> > Ollie
> > 
> > > Regards
> > > 
> > > YH
> > > 
> > _______________________________________________
> > Linuxbios mailing list
> > Linuxbios at clustermatic.org
> > http://www.clustermatic.org/mailman/listinfo/linuxbios
> > 
>