About cache enabling in LWIP port of BBB in RTEMS

Joel Sherrill joel.sherrill at oarcorp.com
Thu Sep 17 20:02:25 UTC 2015


Can of of you guys start a table/spreadsheet about board
and SoC revisions and when we think it is broken and when
it works?

I emailed the BB project lead and he didn't know anything
off hand but suggested subscribing to beagleboard at googlegroups.com
and asking there. Someone there may actually have an answer.

--joel

On 9/17/2015 2:05 PM, Marcos Díaz wrote:
> Ragu,
> I would like you to confirm which revision you have, for this I printed the following registers in the BBB:
>
> 0x44E10600 and 0x44E10604
>
> The first will print something like:
> 1b94402e for BBB rev A5C (XAM3359AZCZ100) ( 1b means rev.A of the microcontroller)
> 2b94402e for BBB rev C  (AM3358BZCZ100) (2b means rev B of the microcontroller)
>
> The second register will print something like:
>
> 20ff0383 for A5c (this means that this is AM3359)
> 20fd0383 for C (this means it is an AM3358).
>
> Please let me know which are this values in your Board.
>
> Thanks!
>
>
>
> On Thu, Sep 17, 2015 at 11:44 AM, Marcos Díaz <marcos.diaz at tallertechnologies.com <mailto:marcos.diaz at tallertechnologies.com>> wrote:
>
>     Yes, sorry about that, There are two registers we can check to see the different revision numbers. I will check it myself once i confirm that the different revisions are the problem (i'm not sure because of what Ragu said). Thanks!
>
>     On Thu, Sep 17, 2015 at 11:12 AM, Joel Sherrill <joel.sherrill at oarcorp.com <mailto:joel.sherrill at oarcorp.com>> wrote:
>
>
>
>         On 9/17/2015 8:43 AM, Marcos Díaz wrote:
>
>             Yes, in my case the older (that doesn't work) revision is a
>             XAM3359AZCZ100
>
>             And the rev C (that works well with cache) is
>             AM3358BZCZ100
>
>
>         Can we determine that in software?
>
>             On Thu, Sep 17, 2015 at 10:32 AM, Joel Sherrill <joel.sherrill at oarcorp.com <mailto:joel.sherrill at oarcorp.com> <mailto:joel.sherrill at oarcorp.com <mailto:joel.sherrill at oarcorp.com>>> wrote:
>
>
>
>                  On September 17, 2015 8:26:41 AM CDT, "Marcos Díaz" <marcos.diaz at tallertechnologies.com <mailto:marcos.diaz at tallertechnologies.com> <mailto:marcos.diaz at tallertechnologies.com <mailto:marcos.diaz at tallertechnologies.com>>> wrote:
>                  >Hi,
>                  >
>                  >How did you see the revision number? if you are using u-boot you can
>                  >pause the start and write printenv and enter to see that:
>                  >
>                  >
>                  >board=am335x
>                  >board_name=A335BNLT
>                  >board_rev=00C0
>                  >
>                  >
>                  >This is in my version.
>                  >
>                  >Please tell me so I can check if is the revision, or perhaps is
>                  >something else in u-boot initialization.
>                  >
>                  >
>                  >For the question Joel asked there is a way:
>                  >
>                  >http://dumb-looks-free.blogspot.com.ar/2014/05/beaglebone-black-bbb-revision-serial.html
>                  >
>                  >apparently, in the eeprom thorugh i2c it is recorded. But first we must
>                  >confirm that is a problem from the revisions, since Ragu has the
>                  >problem in a rev C.
>
>                  Does the SoC itself have a revision number we can read? It may be that newer boards have a newer CPU.
>
>                   >Greetings
>                   >
>                   >
>                   >On Wed, Sep 16, 2015 at 7:22 PM, Joel Sherrill
>                   ><joel.sherrill at oarcorp.com <mailto:joel.sherrill at oarcorp.com> <mailto:joel.sherrill at oarcorp.com <mailto:joel.sherrill at oarcorp.com>>> wrote:
>                   >
>                   >
>                   >
>                   >On 9/16/2015 2:41 PM, ragu nath wrote:
>                   >
>                   >Hi Marcos,
>                   >
>                   >Great news! I did not  find any solution to the issue. I have a REV C
>                   >board from element14. Is this the same board you are using?  In my
>                   >board I saw the issue.
>                   >
>                   >Does this have anything to do with the patch you submitted [PATCH]
>                   >Beaglebone: fix missing clobber in inline assembly.
>                   >https://lists.rtems.org/pipermail/devel/2015-September/012531.html
>                   >I have not yet tested with this patch.
>                   >
>                   >The freebsd driver is working with cache disabled.  If possible pls
>                   >check if it is working with cache enabled in your board.
>                   >
>                   >
>                   >If this is a board revision related issue, is there a way
>                   >programmatically to
>                   >know which revision the board is? That way the BSP could auto-detect
>                   >the right
>                   >thing to do. Otherwise, we may be looking at a BSP variant or a build
>                   >option.
>                   >I would rather avoid those if we can auto-detect.
>                   >
>                   >--joel
>                   >
>                   >
>                   >Thanks,
>                   >Ragunath
>                   >
>                   >
>                   >On Mon, Sep 14, 2015 at 7:22 PM, Marcos Díaz
>                   ><marcos.diaz at tallertechnologies.com <mailto:marcos.diaz at tallertechnologies.com> <mailto:marcos.diaz at tallertechnologies.com <mailto:marcos.diaz at tallertechnologies.com>>
>                   ><mailto:marcos.diaz at tallertechnologies.com <mailto:marcos.diaz at tallertechnologies.com> <mailto:marcos.diaz at tallertechnologies.com <mailto:marcos.diaz at tallertechnologies.com>>>> wrote:
>                   >
>                   >    Hi Ragu,
>                   >I wanted to know if you were able to see something else about the
>                   >problem we had in the BBB when using LWIP and enabling cache ( the
>                   >program freezes).
>                   >I can tell you that here we were using BBB rev. A5C and had this
>                   >problem, but now we could test this with a BBB Rev C, and it
>                   >successfully works with cache enabled (using the same sdcard in both
>                   >boards, one works and the other doesn't).
>                   >    Greetings
>                   >
>                   >    --
>                   >
>                   >    ______________________________
>                   >
>                   >    <http://www.tallertechnologies.com>
>                   >
>                   >    *
>                   >    *
>                   >
>                   >    Marcos Díaz
>                   >
>                   >    Software Engineer
>                   >
>                   >    *
>                   >    *
>                   >
>                   >    San Lorenzo 47, 3rd Floor, Office 5
>                   >
>                   >    Córdoba, Argentina
>                   >
>                   >    *
>                   >    *
>                   >
>                   >    Phone:+54 351 4217888 / +54 351 4218211/ +54 351 7617452
>                   >
>                   >    Skype:markdiaz22
>                   >
>                   >
>                   >
>                   >
>                   >
>                   >--
>                   >ragu
>                   >
>                   >
>                   >--
>                   >Joel Sherrill, Ph.D.             Director of Research & Development
>                   >joel.sherrill at OARcorp.com        On-Line Applications Research
>                   >Ask me about RTEMS: a free RTOS  Huntsville AL 35805
>                   >Support Available                (256) 722-9985
>                   >
>                   >
>                   >
>                   >
>                   >--
>                   >
>                   >______________________________
>                   >
>                   >
>                   >
>                   >
>                   >Marcos Díaz
>                   >
>                   >Software Engineer
>                   >
>                   >
>                   >San Lorenzo 47, 3rd Floor, Office 5
>                   >
>                   >Córdoba, Argentina
>                   >
>                   >
>                   >Phone: +54 351 4217888 / +54 351 4218211/ +54 351 7617452
>                   >
>                   >Skype: markdiaz22
>
>                  --joel
>
>
>
>
>             --
>
>             ______________________________
>
>             <http://www.tallertechnologies.com>
>
>             *
>             *
>
>             Marcos Díaz
>
>             Software Engineer
>
>             *
>             *
>
>             San Lorenzo 47, 3rd Floor, Office 5
>
>             Córdoba, Argentina
>
>             *
>             *
>
>             Phone:+54 351 4217888 / +54 351 4218211/ +54 351 7617452
>
>             Skype:markdiaz22
>
>
>
>         --
>         Joel Sherrill, Ph.D.             Director of Research & Development
>         joel.sherrill at OARcorp.com        On-Line Applications Research
>         Ask me about RTEMS: a free RTOS  Huntsville AL 35805
>         Support Available                (256) 722-9985
>
>
>
>
>     --
>
>     ______________________________
>
>     <http://www.tallertechnologies.com>
>
>     *
>     *
>
>     Marcos Díaz
>
>     Software Engineer
>
>     *
>     *
>
>     San Lorenzo 47, 3rd Floor, Office 5
>
>     Córdoba, Argentina
>
>     *
>     *
>
>     Phone:+54 351 4217888 / +54 351 4218211/ +54 351 7617452
>
>     Skype:markdiaz22
>
>
>
>
>
> --
>
> ______________________________
>
> <http://www.tallertechnologies.com>
>
> *
> *
>
> Marcos Díaz
>
> Software Engineer
>
> *
> *
>
> San Lorenzo 47, 3rd Floor, Office 5
>
> Córdoba, Argentina
>
> *
> *
>
> Phone:+54 351 4217888 / +54 351 4218211/ +54 351 7617452
>
> Skype:markdiaz22
>
>

-- 
Joel Sherrill, Ph.D.             Director of Research & Development
joel.sherrill at OARcorp.com        On-Line Applications Research
Ask me about RTEMS: a free RTOS  Huntsville AL 35805
Support Available                (256) 722-9985



More information about the devel mailing list