How can I make flash writeable?

[Mark Bishop]

I am still trying to get JFFS2 onto the 8313E-RDB.  The procedure in  
the manual isn't working.  What did you use to put JFFS2 on there?


Quoting Duy-Ky Nguyen <duykynguyen at hotmail.com>:

> Dear Wolfgang Denk,
>
> I totally agree ramdisk filesystem is writable. However, for this  
> particular MPC8313E-RDB with FreeScale BSP Linux via LTIB (Linux  
> Traget Image Builder), based on the BSP document, I did try ramdisk  
> and unable to save change after power recycle. That's why I had to  
> try JFFS2 and it did save my change after power recycle .
>
> It's even more confusing when I tried to recreate ramdisk image  
> using LTIB and found ramdisk is of type EXT2, which is writable  
> filesystem !?!?
>
> Best Regards,
>
> Duy-Ky
>
> ----- Original Message ----- From: <linuxppc-embedded-request at ozlabs.org>
> To: <linuxppc-embedded at ozlabs.org>
> Sent: Saturday, October 18, 2008 6:00 PM
> Subject: Linuxppc-embedded Digest, Vol 50, Issue 31
>
>
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>> When replying, please edit your Subject line so it is more specific
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>>
>> Today's Topics:
>>
>>  1. Re: How can I make flash writeable? (Duy-Ky Nguyen)
>>  2. Re: Cache control (Grant Likely)
>>  3. Re: How can I make flash writeable? (Wolfgang Denk)
>>  4. Related to Keypad Driver .... (Misbah khan)
>>
>>
>> ----------------------------------------------------------------------
>>
>> Message: 1
>> Date: Fri, 17 Oct 2008 18:19:38 -0700
>> From: "Duy-Ky Nguyen" <duykynguyen at hotmail.com>
>> Subject: Re: How can I make flash writeable?
>> To: <linuxppc-embedded at ozlabs.org>
>> Message-ID: <BLU119-DAV13B797B2CC811E90F87406BB2D0 at phx.gbl>
>> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
>> reply-type=original
>>
>> Hi Mark,
>>
>> I guess you want to have RW filesystem for your Linux target.
>> If that's the case you need to have root filesystem as JFFS2.
>>
>> There's a document MPC8313E-RDB BSP User's Guide comes with the MPC8313E-RDB
>> package.
>> It has all info for several filesystems like NFS (network), Ramdisk
>> (Read-Only), and JFFS2 (Read/Write)
>>
>> Regards,
>>
>> Duy-Ky
>>
>> ----- Original Message ----- From: <linuxppc-embedded-request at ozlabs.org>
>> To: <linuxppc-embedded at ozlabs.org>
>> Sent: Friday, October 17, 2008 6:00 PM
>> Subject: Linuxppc-embedded Digest, Vol 50, Issue 30
>>
>>
>>> Send Linuxppc-embedded mailing list submissions to
>>> linuxppc-embedded at ozlabs.org
>>>
>>> To subscribe or unsubscribe via the World Wide Web, visit
>>> https://ozlabs.org/mailman/listinfo/linuxppc-embedded
>>> or, via email, send a message with subject or body 'help' to
>>> linuxppc-embedded-request at ozlabs.org
>>>
>>> You can reach the person managing the list at
>>> linuxppc-embedded-owner at ozlabs.org
>>>
>>> When replying, please edit your Subject line so it is more specific
>>> than "Re: Contents of Linuxppc-embedded digest..."
>>>
>>>
>>> Today's Topics:
>>>
>>>  1. Re: How can I make flash writeable? (Mark Bishop)
>>>  2. Re: How can I make flash writeable? (Marco Stornelli)
>>>  3. Re: Loadable module crashes at kernel stack overflow or
>>>     machine check (Ben Gardiner)
>>>  4. Re: Oops in during system run (Scott Wood)
>>>
>>>
>>> ----------------------------------------------------------------------
>>>
>>> Message: 1
>>> Date: Fri, 17 Oct 2008 08:33:52 -0400
>>> From: Mark Bishop <mark at bish.net>
>>> Subject: Re: How can I make flash writeable?
>>> To: linuxppc-embedded at ozlabs.org
>>> Message-ID: <20081017083352.hvn0g2q1es8skcwg at www.bish.net>
>>> Content-Type: text/plain; charset=ISO-8859-1; DelSp="Yes";
>>> format="flowed"
>>>
>>>
>>>
>>> Ok, so bear with me.  I've read booting-without-of.txt in the
>>> Documentation/powerpc directory and I modified a .dts file but now what?
>>>
>>> I use ltib or u-boot to load that into the device or do I roll a
>>> kernel with that file and flash the device with it?
>>>
>>> Apologies for the less than technical questions.
>>>
>>> Quoting Marco Stornelli <marco.stornelli at coritel.it>:
>>>
>>>> Hi Mark,
>>>>
>>>>> How can I tell which devices are mapped to /proc/mtd devices?
>>>>
>>>> If I well understand the question, you'd like to change the partitions
>>>> layout (?), so you should check out the dts file to see the flash
>>>> layout, then you can specify there the partitions and change the
>>>> dimensions, if they are read-only...and so on.
>>>>
>>>> Regards,
>>>>
>>>> Mark Bishop ha scritto:
>>>>> I am using the MPC8313E-RDB and I am having some problems using the
>>>>> flash that comes on the board.  Let me preface this by saying that I
>>>>> haven't worked in the embedded linux arena in about 10 years so I am
>>>>> trying to catch up with all the new toys.
>>>>>
>>>>> This board uses uBoot and it currently has 128M of DDR2, 8M flash and
>>>>> 32M NAND Flash.  I have a few questions:
>>>>>
>>>>> How can I tell which memory device it uses to boot out of?
>>>>> How can I tell which devices are mapped to /proc/mtd devices?
>>>>>
>>>>>
>>>>> I want to create a writeable flash partition, is there a FAQ out there I
>>>>> could look at.
>>>>>
>>>>> All of this is after a few days of using Google to try and glean some
>>>>> data from the internet.  And the books don't get here from Amazon until
>>>>> Monday.
>>>>>
>>>>> I would appreciate any help.  Even a RTFM - if you could point me to
>>>>> TFM, it would greatly help.
>>>>> _______________________________________________
>>>>> Linuxppc-embedded mailing list
>>>>> Linuxppc-embedded at ozlabs.org
>>>>> https://ozlabs.org/mailman/listinfo/linuxppc-embedded
>>>>>
>>>>
>>>> --
>>>> Marco Stornelli
>>>> Embedded Software Engineer
>>>> CoRiTeL - Consorzio di Ricerca sulle Telecomunicazioni
>>>> http://www.coritel.it
>>>>
>>>> marco.stornelli at coritel.it
>>>> +39 06 72582838
>>>>
>>>>
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 2
>>> Date: Fri, 17 Oct 2008 15:13:58 +0200
>>> From: Marco Stornelli <marco.stornelli at coritel.it>
>>> Subject: Re: How can I make flash writeable?
>>> To: Mark Bishop <mark at bish.net>
>>> Cc: linuxppc-embedded at ozlabs.org
>>> Message-ID: <48F88F96.3000804 at coritel.it>
>>> Content-Type: text/plain; charset=us-ascii
>>>
>>> You have to compile it with the dtc compiler and load it with the uboot
>>> bootm command, indeed, (at least with a recent uboot version) it has
>>> three parameters: kernel, dtb (the name of dts compiled) and initrd. If
>>> you want you can store the dtb in flash.
>>>
>>> Regards,
>>>
>>> Mark Bishop ha scritto:
>>>>
>>>>
>>>> Ok, so bear with me.  I've read booting-without-of.txt in the
>>>> Documentation/powerpc directory and I modified a .dts file but now what?
>>>>
>>>> I use ltib or u-boot to load that into the device or do I roll a kernel
>>>> with that file and flash the device with it?
>>>>
>>>> Apologies for the less than technical questions.
>>>>
>>>> Quoting Marco Stornelli <marco.stornelli at coritel.it>:
>>>>
>>>>> Hi Mark,
>>>>>
>>>>>> How can I tell which devices are mapped to /proc/mtd devices?
>>>>>
>>>>> If I well understand the question, you'd like to change the partitions
>>>>> layout (?), so you should check out the dts file to see the flash
>>>>> layout, then you can specify there the partitions and change the
>>>>> dimensions, if they are read-only...and so on.
>>>>>
>>>>> Regards,
>>>>>
>>>>> Mark Bishop ha scritto:
>>>>>> I am using the MPC8313E-RDB and I am having some problems using the
>>>>>> flash that comes on the board.  Let me preface this by saying that I
>>>>>> haven't worked in the embedded linux arena in about 10 years so I am
>>>>>> trying to catch up with all the new toys.
>>>>>>
>>>>>> This board uses uBoot and it currently has 128M of DDR2, 8M flash and
>>>>>> 32M NAND Flash.  I have a few questions:
>>>>>>
>>>>>> How can I tell which memory device it uses to boot out of?
>>>>>> How can I tell which devices are mapped to /proc/mtd devices?
>>>>>>
>>>>>>
>>>>>> I want to create a writeable flash partition, is there a FAQ out there
>>>>>> I
>>>>>> could look at.
>>>>>>
>>>>>> All of this is after a few days of using Google to try and glean some
>>>>>> data from the internet.  And the books don't get here from Amazon until
>>>>>> Monday.
>>>>>>
>>>>>> I would appreciate any help.  Even a RTFM - if you could point me to
>>>>>> TFM, it would greatly help.
>>>>>> _______________________________________________
>>>>>> Linuxppc-embedded mailing list
>>>>>> Linuxppc-embedded at ozlabs.org
>>>>>> https://ozlabs.org/mailman/listinfo/linuxppc-embedded
>>>>>>
>>>>>
>>>>> -- 
>>>>> Marco Stornelli
>>>>> Embedded Software Engineer
>>>>> CoRiTeL - Consorzio di Ricerca sulle Telecomunicazioni
>>>>> http://www.coritel.it
>>>>>
>>>>> marco.stornelli at coritel.it
>>>>> +39 06 72582838
>>>>>
>>>>>
>>>>
>>>> _______________________________________________
>>>> Linuxppc-embedded mailing list
>>>> Linuxppc-embedded at ozlabs.org
>>>> https://ozlabs.org/mailman/listinfo/linuxppc-embedded
>>>>
>>>
>>> -- 
>>> Marco Stornelli
>>> Embedded Software Engineer
>>> CoRiTeL - Consorzio di Ricerca sulle Telecomunicazioni
>>> http://www.coritel.it
>>>
>>> marco.stornelli at coritel.it
>>> +39 06 72582838
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 3
>>> Date: Fri, 17 Oct 2008 09:12:07 -0400
>>> From: Ben Gardiner <BenGardiner at nanometrics.ca>
>>> Subject: Re: Loadable module crashes at kernel stack overflow or
>>> machine check
>>> To: Ganesh Kumar N M <ganeshkumar at signal-networks.com>
>>> Cc: linuxppc-dev at ozlabs.org, linuxppc-embedded at ozlabs.org
>>> Message-ID: <48F88F27.4040107 at nanometrics.ca>
>>> Content-Type: text/plain; charset="iso-8859-1"; Format="flowed"
>>>
>>> Ganesh Kumar N M wrote:
>>>> *Hi All,*
>>>> **
>>>> *    I'm working on MPC860 with Montavista linux 2.4.18*
>>>> *We have a Linux kernel loadable module which on loading*
>>>> *panicks after some random time say 8 hours, 4 hours or so*
>>>> *the oops outputs say either machine check exception or *
>>>> *kernel stack overflow (randomly both show up) a**re as below:*
>>> I don't know for sure what could be causing your problem. I can only
>>> suggest some patches that have helped us in the past.
>>>
>>> I'm not familiar with Montavista's kernel versions; but I know our
>>> 2.4.24 kernel did not have the 'separate I-TLB error and miss handling'
>>> patch (
>>> http://ozlabs.org/pipermail/linuxppc-embedded/2005-January/016382.html )
>>> which caused our applications to segfault for not apparent reason.
>>>
>>> I also suggest applying the CPU15 fix (
>>> http://git.denx.de/?p=linuxppc_2_4_devel.git;a=commit;h=baf9a6caca75b1f338ae370669e5882809000164
>>> and
>>> http://git.denx.de/?p=linuxppc_2_4_devel.git;a=commit;h=3ad403717f1d9c6a09ec41a5b016ac5245591122
>>> ) and enabling it temporarily to see if the problem could be the unlucky
>>> placement of a branch instruction at the end of a page; but evaluate the
>>> performance of your application carefully if you are considering running
>>> production code with the patch enabled as it introduces significant
>>> overhead.
>>>
>>> Regards,
>>>
>>> Ben Gardiner
>>> Nanometrics Seismological Instruments
>>> 250 Herzberg Rd., Kanata, ON, CA, K2K 2A1
>>> -------------- next part --------------
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>>>
>>> ------------------------------
>>>
>>> Message: 4
>>> Date: Fri, 17 Oct 2008 10:21:32 -0500
>>> From: Scott Wood <scottwood at freescale.com>
>>> Subject: Re: Oops in during system run
>>> To: Sreejith <sreejithmm at tataelxsi.co.in>
>>> Cc: linuxppc-dev at ozlabs.org, linuxppc-embedded at ozlabs.org
>>> Message-ID: <20081017152129.GA19584 at ld0162-tx32.am.freescale.net>
>>> Content-Type: text/plain; charset=us-ascii
>>>
>>> On Fri, Oct 17, 2008 at 03:49:12PM +0530, Sreejith wrote:
>>>> This is a peculiar Oops we are encountering during the running of our
>>>> board
>>>> (sh4) architecture
>>>
>>> So why are you posting to powerpc lists?
>>>
>>>> PC  : 844240f8 SP  : 88d1ff44 SR  : 400080f0 TEA : c0169d64    Tainted: P
>>>
>>> With proprietary modules, too.
>>>
>>>> Give you valuable suggestions!!
>>>
>>> Debug the code?
>>> Switch to powerpc? :-)
>>>
>>> -Scott
>>>
>>>
>>> ------------------------------
>>>
>>> _______________________________________________
>>> Linuxppc-embedded mailing list
>>> Linuxppc-embedded at ozlabs.org
>>> https://ozlabs.org/mailman/listinfo/linuxppc-embedded
>>>
>>> End of Linuxppc-embedded Digest, Vol 50, Issue 30
>>> *************************************************
>>>
>>
>>
>>
>> ------------------------------
>>
>> Message: 2
>> Date: Sat, 18 Oct 2008 00:32:47 -0600
>> From: Grant Likely <grant.likely at secretlab.ca>
>> Subject: Re: Cache control
>> To: Robert Woodworth <rwoodworth at securics.com>
>> Cc: linuxppc-embedded <linuxppc-embedded at ozlabs.org>
>> Message-ID: <20081018063246.GA5594 at secretlab.ca>
>> Content-Type: text/plain; charset=us-ascii
>>
>> On Thu, Oct 16, 2008 at 09:57:27AM -0600, Robert Woodworth wrote:
>>> I have a Virtex4 VF60 device with 256MB DDR2.
>>>
>>> I have told the Linux kernel that the device has only 128MB and its
>>> working fine.  There is an HDL module that is populating the next 16MB
>>> with sensor data (0x08000000 - 0x09000000)  I mapped the area into my
>>> driver via `ioremap()` and also via `mmap / remap_pfn_range()`  It works
>>> fine.
>>>
>>> I know that PPC cache regions work in 128MB blocks.  I assume that the
>>> kernel bootup is turning on cache in the first 128, because it thinks
>>> that its the full RAM range, and not cached in the next 128MB.
>>
>> That's only true when the MMU is off.  Linux runs with the MMU on and
>> the TLB entries specify the caching per mapping.
>>
>>> I know that if I declare the area cached, and invalidate the region
>>> before I read it,  the reads should be much faster than if it's not
>>> cached.
>>
>> Correct.
>>
>>> How can I control if the area is cached? and then invalidate it when new
>>> data arrives?
>>>
>>> Is there a PPC/Linux API call to declare the region cached and
>>> invalidate regions before read?
>>
>> Take a look at dma_alloc_coherent() and related functions.
>>
>> Cheers,
>> g.
>>
>>
>>
>> ------------------------------
>>
>> Message: 3
>> Date: Sat, 18 Oct 2008 09:53:16 +0200
>> From: Wolfgang Denk <wd at denx.de>
>> Subject: Re: How can I make flash writeable?
>> To: "Duy-Ky Nguyen" <duykynguyen at hotmail.com>
>> Cc: linuxppc-embedded at ozlabs.org
>> Message-ID: <20081018075316.11AB0835697A at gemini.denx.de>
>> Content-Type: text/plain; charset=ISO-8859-1
>>
>> Dear "Duy-Ky Nguyen",
>>
>> In message <BLU119-DAV13B797B2CC811E90F87406BB2D0 at phx.gbl> you wrote:
>>>
>>> I guess you want to have RW filesystem for your Linux target.
>>> If that's the case you need to have root filesystem as JFFS2.
>>
>> This is not correct. You can use a read-only root file system combined
>> with additionala ,writable file systems.
>>
>>> There's a document MPC8313E-RDB BSP User's Guide comes with the  
>>> MPC8313E-RDB
>>> package.
>>> It has all info for several filesystems like NFS (network), Ramdisk
>>> (Read-Only), and JFFS2 (Read/Write)
>>
>> That's incorrect, either. A ramdisk is usually writable (unless you
>> mount it read-only, which would be very unusuak).
>>
>> See also
>> http://www.denx.de/wiki/view/DULG/RootFileSystemDesignAndBuilding
>>
>> Best regards,
>>
>> Wolfgang Denk
>>
>> -- 
>> DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
>> HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
>> Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
>> To get something done, a committee should consist  of  no  more  than
>> three men, two of them absent.
>>
>>
>> ------------------------------
>>
>> Message: 4
>> Date: Sat, 18 Oct 2008 08:26:07 -0700 (PDT)
>> From: Misbah khan <misbah_khan at engineer.com>
>> Subject: Related to Keypad Driver ....
>> To: linuxppc-embedded at ozlabs.org
>> Message-ID: <20047836.post at talk.nabble.com>
>> Content-Type: text/plain; charset=us-ascii
>>
>>
>> Hi all ...
>>
>> If any of you have worked on key pad driver could you please guide me how to
>> write the same as in the most standard form ...
>>
>> I have a CPLD from Whre i have to read the key physical status (debouncing
>> logic in CPLD itself) on interrupt this i have to pass to the application
>> which ever is using keys for its operation and control ....
>>
>> The concern is this ...
>>
>>
>> What could the best way of passing the virtual key status to the application
>> and how it is done in linux drivers ???? How should i make the API waiting
>> for Key event and Getting Unblocked ???? Can i make the API as a thread
>> waiting for signal ??? The same API application could use ... How is it done
>> in Standard Keyboard Drivers ???
>>
>> A code snipped or Documentation would really help me ...
>>
>>
>> I am not sure what way i should proceed ...If any one implemented a Keypad
>> driver or can suggest your experience
>>
>>
>> Thanks in Advance ...
>>
>> Misbah <><
>> -- 
>> View this message in context:  
>> http://www.nabble.com/Related-to-Keypad-Driver-....-tp20047836p20047836.html
>> Sent from the linuxppc-embedded mailing list archive at Nabble.com.
>>
>>
>>
>> ------------------------------
>>
>> _______________________________________________
>> Linuxppc-embedded mailing list
>> Linuxppc-embedded at ozlabs.org
>> https://ozlabs.org/mailman/listinfo/linuxppc-embedded
>>
>> End of Linuxppc-embedded Digest, Vol 50, Issue 31
>> *************************************************
>>
>
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