Help! AMD Config Advice

Help! AMD Config Advice

[Frank R Callaghan]

Is there no solution to this question ?
am I asking the wronge group ?
is it so stupid it does not deserve a responce ?

----------  Forwarded Message  ----------

Subject: AMD Config Advice
Date: Thu, 19 Dec 2002 15:31:19 -0500
From: Frank R Callaghan <f.callaghan@ieee.org>
To: LinuxMTD <linux-mtd@lists.infradead.org>

Hi,

I undrstand this may be a very basic question, but here go's

I am looking to use an AMD flash chip on my pc104 card
to store some non-volatile data, the chip is a 2MB part  AMD29F016,
the BIOS is in the top 128KB of the first mega-byte(do not want to
 overwrite).

After setting up the kernel with MDT I get
cat /proc/mtd
dev:    size   erasesize  name
mtd0: 00200000 00010000 "Physically mapped flash"

ok but I only need the second 1MB - is there some way to 
prevent the first meg being mapped/used ?

Kernal Version 2.4.19 with:
#
# Memory Technology Devices (MTD)
#
CONFIG_MTD=y
CONFIG_MTD_DEBUG=y
CONFIG_MTD_DEBUG_VERBOSE=3
# CONFIG_MTD_PARTITIONS is not set
# CONFIG_MTD_CONCAT is not set
# CONFIG_MTD_REDBOOT_PARTS is not set
# CONFIG_MTD_CHAR is not set
CONFIG_MTD_BLOCK=y
CONFIG_FTL=y
# CONFIG_NFTL is not set
#
# RAM/ROM/Flash chip drivers
#
CONFIG_MTD_CFI=y
CONFIG_MTD_JEDECPROBE=y
CONFIG_MTD_GEN_PROBE=y
# CONFIG_MTD_CFI_ADV_OPTIONS is not set
# CONFIG_MTD_CFI_INTELEXT is not set
CONFIG_MTD_CFI_AMDSTD=y
# CONFIG_MTD_RAM is not set
# CONFIG_MTD_ROM is not set
# CONFIG_MTD_ABSENT is not set
# CONFIG_MTD_OBSOLETE_CHIPS is not set
# CONFIG_MTD_AMDSTD is not set
# CONFIG_MTD_SHARP is not set
# CONFIG_MTD_JEDEC is not set
#
# Mapping drivers for chip access
#
CONFIG_MTD_PHYSMAP=y
CONFIG_MTD_PHYSMAP_START=9500000		<- My phy addr of second MB
CONFIG_MTD_PHYSMAP_LEN=100000		<-- 1MB
CONFIG_MTD_PHYSMAP_BUSWIDTH=1
# CONFIG_MTD_PNC2000 is not set
# CONFIG_MTD_SC520CDP is not set
# CONFIG_MTD_NETSC520 is not set
# CONFIG_MTD_SBC_GXX is not set
# CONFIG_MTD_ELAN_104NC is not set
# CONFIG_MTD_DILNETPC is not set
# CONFIG_MTD_MIXMEM is not set
# CONFIG_MTD_OCTAGON is not set
# CONFIG_MTD_VMAX is not set
# CONFIG_MTD_L440GX is not set
# CONFIG_MTD_AMD766ROM is not set
# CONFIG_MTD_ICH2ROM is not set
# CONFIG_MTD_PCI is not set
#
# Self-contained MTD device drivers
#
# CONFIG_MTD_PMC551 is not set
# CONFIG_MTD_SLRAM is not set
# CONFIG_MTD_MTDRAM is not set
# CONFIG_MTD_BLKMTD is not set
# CONFIG_MTD_DOC1000 is not set
# CONFIG_MTD_DOC2000 is not set
# CONFIG_MTD_DOC2001 is not set
# CONFIG_MTD_DOCPROBE is not set

also I'm looking to use jffs2 as the file system - maybe I can partion it
to only use the second meg ???

TIA,
        Frank.







______________________________________________________
Linux MTD discussion mailing list
http://lists.infradead.org/mailman/listinfo/linux-mtd/

-------------------------------------------------------

Re: Help! AMD Config Advice

[Eli Carter]

Frank R Callaghan wrote:
> Is there no solution to this question ?
> am I asking the wronge group ?
> is it so stupid it does not deserve a responce ?
> 
> ----------  Forwarded Message  ----------
> 
> Subject: AMD Config Advice
> Date: Thu, 19 Dec 2002 15:31:19 -0500
> From: Frank R Callaghan <f.callaghan@ieee.org>
> To: LinuxMTD <linux-mtd@lists.infradead.org>
> 
> Hi,
> 
> I undrstand this may be a very basic question, but here go's
> 
> I am looking to use an AMD flash chip on my pc104 card
> to store some non-volatile data, the chip is a 2MB part  AMD29F016,
> the BIOS is in the top 128KB of the first mega-byte(do not want to
>  overwrite).
> 
> After setting up the kernel with MDT I get
> cat /proc/mtd
> dev:    size   erasesize  name
> mtd0: 00200000 00010000 "Physically mapped flash"
> 
> ok but I only need the second 1MB - is there some way to 
> prevent the first meg being mapped/used ?
> 
> Kernal Version 2.4.19 with:
[snip config]
> also I'm looking to use jffs2 as the file system - maybe I can partion it
> to only use the second meg ???

You should be able to partition the MTD device by the commandline or a 
redboot table.
I believe jffs2 requires at least 5 'sectors' on the chip, though I've 
not used it.  You would need to check the layout of your device has 
enough for it.
That's about the extent of my knowledge at the moment... I hope it gives 
you enough to google on...

HTH,

Eli
--------------------. "If it ain't broke now,
Eli Carter           \                  it will be soon." -- crypto-gram
eli.carter(a)inet.com `-------------------------------------------------

Re: Help! AMD Config Advice

[Jörn Engel]

On Thu, 9 January 2003 11:46:13 -0500, Frank R Callaghan wrote:
> Subject: Help! AMD Config Advice
> 
> Is there no solution to this question ?
> am I asking the wronge group ?
> is it so stupid it does not deserve a responce ?

It had the correct subject to be ignored. ;)

> I am looking to use an AMD flash chip on my pc104 card
> to store some non-volatile data, the chip is a 2MB part  AMD29F016,
> the BIOS is in the top 128KB of the first mega-byte(do not want to
>  overwrite).
> 
> After setting up the kernel with MDT I get
> cat /proc/mtd
> dev:    size   erasesize  name
> mtd0: 00200000 00010000 "Physically mapped flash"
> 
> ok but I only need the second 1MB - is there some way to 
> prevent the first meg being mapped/used ?

Maybe, but you have already tried the obvious. And it is a very odd
request, that you have too _much_ storage. 

My first guess is that physmap calls up the cfi probing. cfi tells the
kernel about a 2MiB-Chip and that is what the kernel uses. Whether
this is correct behaviour or not, I don't want to decide.

> also I'm looking to use jffs2 as the file system - maybe I can partion it
> to only use the second meg ???

This would be the easiest. Easiest is to copy physmap.c and hardcode
the partitioning, as is already done dozens of time. Not pretty, but
simple.


Jörn

-- 
"Security vulnerabilities are here to stay."
-- Scott Culp, Manager of the Microsoft Security Response Center, 2001