[U-Boot-Users] MPC8540 FEC/TSEC -Issues while enabling both controllers

[U-Boot-Users] MPC8540 FEC/TSEC -Issues while enabling both controllers

[Sudhakar]

 Hi all..

I have some issues in Uboot while enabling both the controllers FEC/TSEC in 
MPC8540 based board..

Individually they are working fine..but when enabled together , both  are not 
working.

Now im trying to analyze why they are not working ?

If anyone can provide me details to enable both it would save some time for 
me.

-- 
Thanks and Regards,
Sudhakar V

[U-Boot-Users] What is the most simple ppc405gp board

[Tadas]

What ppc405gp board is cheapest, and have minimum hardware?

Or more excactly, which board DO NOT have real time clock and preferably no
fpga.
and if the ram is integrated with no upgrade support it  would be perfect.

I want to use its code as referense.
if the board have something more then it is hard to remove.


And maybe someone know is it posible tu run linux without RTC?

[U-Boot-Users] What is the most simple ppc405gp board

[Wolfgang Denk]

In message <001a01c496d5$c2873da0$030aa8c0@t> you wrote:
> What ppc405gp board is cheapest, and have minimum hardware?

Strange request.

> I want to use its code as referense.
> if the board have something more then it is hard to remove.

I think you misunderstand. It is MUCH easier to  remove  support  for
things (just disable the config options) than adding something.

> And maybe someone know is it posible tu run linux without RTC?

Sure. Linux does not need any RTC.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at denx.de
Systems programmers are the high priests of a low cult.
                                                       -- R.S. Barton

[U-Boot-Users] What is the most simple ppc405gp board

[Stefan Roese]

Hi Tadas,

> What ppc405gp board is cheapest, and have minimum hardware?

DO you what to by one or only use the U-Boot port as a starting point
for your board?
 
> Or more excactly, which board DO NOT have real time clock and 
> preferably no
> fpga.
> and if the ram is integrated with no upgrade support it  
> would be perfect.
> 
> I want to use its code as referense.
> if the board have something more then it is hard to remove.

Hmmm. I find it pretty easy to remove something from U-Boot. I would
suggest to start with the CPCI4052 and remove all stuff you don't need
(FPGA, RTC, etc.).
 
> And maybe someone know is it posible tu run linux without RTC?

Yes. We do it on some of our boards.

Best regards,
Stefan

[U-Boot-Users] What is the most simple ppc405gp board

[Tadas]

> > What ppc405gp board is cheapest, and have minimum hardware?
>
> DO you what to by one or only use the U-Boot port as a starting point
> for your board?

I have most simple ppc405gp board and need to port bootloader, and linux to
it.
there is no aditional hardware just integrated 8mb ram cpu, ethernet, and
one pci slot.
so I should remove everything from any other board code to port it.

> > Or more excactly, which board DO NOT have real time clock and
> > preferably no
> > fpga.
> > and if the ram is integrated with no upgrade support it
> > would be perfect.
> >
> > I want to use its code as referense.
> > if the board have something more then it is hard to remove.
>
> Hmmm. I find it pretty easy to remove something from U-Boot. I would
> suggest to start with the CPCI4052 and remove all stuff you don't need
> (FPGA, RTC, etc.).

FPGA , RTC is easy to remove from u-boot, but I dont know how remove them
from linux.
and RTC seems to be vital part to run linux. (I found somewhere that it is
nesecary to calculate bogomips)
so probably some special driver is nesecary.

> > And maybe someone know is it posible tu run linux without RTC?
> Yes. We do it on some of our boards.
OK, i will try to use CPCI4052 code.

[U-Boot-Users] What is the most simple ppc405gp board

[Stefan Roese]

Hi Tadas,

> I have most simple ppc405gp board and need to port 
> bootloader, and linux to
> it.
> there is no aditional hardware just integrated 8mb ram cpu, 
> ethernet, and
> one pci slot.
> so I should remove everything from any other board code to port it.

Yes!

> > > Or more excactly, which board DO NOT have real time clock and
> > > preferably no
> > > fpga.
> > > and if the ram is integrated with no upgrade support it
> > > would be perfect.
> > >
> > > I want to use its code as referense.
> > > if the board have something more then it is hard to remove.
> >
> > Hmmm. I find it pretty easy to remove something from U-Boot. I would
> > suggest to start with the CPCI4052 and remove all stuff you 
> don't need
> > (FPGA, RTC, etc.).
> 
> FPGA , RTC is easy to remove from u-boot, but I dont know how 
> remove them
> from linux.
> and RTC seems to be vital part to run linux. (I found 
> somewhere that it is
> nesecary to calculate bogomips)
> so probably some special driver is nesecary.

No, not needed at all! Just configure your kernel without RTC!

Best regards,
Stefan

[U-Boot-Users] ppc405gp cpu problems

[Tadas]

Hello,
I still have lots of problems with my board.
ppc405gp board. 8mb ram, 1mb flash, 1 pci , ethernet.
Mostly with linux, but  also with bootloader.


first problem with bootloader:
(this is default code for all ppc405 boards )
----------------------------------
_start:
addi r4,r0,0x0000  // second command executed after reset
mtspr sgr,r4
mtspr dcwr,r4
mtesr r4 /* clear Exception Syndrome Reg */
mttcr r4 /* clear Timer Control Reg */
mtxer r4 /* clear Fixed-Point Exception Reg */
mtevpr r4 /* clear Exception Vector Prefix Reg */
addi r4,r0,0x1000 /* set ME bit (Machine Exceptions) */
oris r4,r4,0x0002 /* set CE bit (Critical Exceptions) */

// mtmsr r4 /* change MSR */  this command creates exception 0x200
                    (machine check exception)  so I need to comment it out,
                    anyway it still works without it.

addi r4,r0,(0xFFFF-0x10000) /* set r4 to 0xFFFFFFFF (status in the */
/* dbsr is cleared by setting bits to 1) */
mtdbsr r4 /* clear/reset the dbsr */
........---------------------------------------
how that can happen?
Seems everybody else is executing this code without problems

***

Another problem is with MMU on linux.
cpu crashes almost immediately at start.
when linux atempts to initialize MMU

.text:C0000018 turn_on_mmu:
.text:C0000018                 lis     r0, 2 # 0x21232
.text:C000001C                 ori     r0, r0, 0x1232 # 0x21232
.text:C0000020                 mtsrr1  r0
.text:C0000024                 lis     r0, (start_here >> 16) # 0xC0002250
.text:C0000028                 ori     r0, r0, (start_here & 0xFFFF)
.text:C000002C                 mtsrr0  r0
.text:C0000030                 rfi

then it should jump to start_here function

text:C0002250 start_here:
.text:C0002250                 lis     rtoc, (init_task >> 16) # 0xC00D7150
.text:000000200 .......
and and here it crashes, "Machine check exception" hapens.
looks like mmu is initialized incorectly, or it attempts to execute from
nonexsisting  memory,
I can view that virtual memory until first command execution, and then it
disaperars. seems cpu goes into r

I cant understand this, seems no board dependent code is even executed,
averything happerns very early in first attempt to initilaize MMU
(but if mmu is initialized from exeption handler code it works.)
everybody else is also runnig that code without problems,
because it is same on all linux kernels.
I have tested 2 boards and all behave in same way.
What can cause such behavior? Or these cpu have some defect?

[U-Boot-Users] ppc405gp cpu problems

[Wolfgang Denk]

In message <008d01c4986d$8293fb90$030aa8c0@t> you wrote:
>
> first problem with bootloader:
...
> Seems everybody else is executing this code without problems

Indeed. Are you sure your CPU can read  the  flash  contents  without
problems?

> Another problem is with MMU on linux.
> cpu crashes almost immediately at start.
> when linux atempts to initialize MMU

How do you know? Are you using a JTAG debugger? Which  one/  Does  it
understand  to  use virtual addresses, and is it configured correctly
for this?

> What can cause such behavior? Or these cpu have some defect?

I guess you are using an  inappropriate  and/or  misconfigured  tool.
Additionally,  there  might  be the typical RAM problems you can read
about in at least 9 out of 10 postings on tis list.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at denx.de
8 Catfish                                               = 1 Octo-puss

[U-Boot-Users] ppc405gp cpu problems

[Tadas]

Second problem  solved, seems cpu realy behave strangely,
I placed ram initialization at the very begining of bootloader and now it
works.
also there was some incorect timing but it is not likely to cause problem,
(becase fixing that did not helped)
ram just must be initialized before any other peripherials
(dont know why but now it works ok) at first the first thing initilalized
was UART.


>>>
>>> first problem with bootloader:
>>>...
>>> Seems everybody else is executing this code without problems

>Indeed. Are you sure your CPU can read  the  flash  contents  without
>problems?


The reson of this one is till unknown, but it does not matter, anyway.

I also found, that some time ago this instruction  also was removed on
ppcboot so someone
had this problem too.
http://cvs.tuxbox.org/cgi-bin/viewcvs.cgi/tuxbox/boot/ppcboot/ppc4xx/Attic/start.S?rev=1.2&content-type=text/vnd.viewcvs-markup

#if 1  /* test-only */
        addi    r4,r0,0x1000          // set ME bit (Machine Exceptions)
        oris    r4,r4,0x0002          // set CE bit (Critical Exceptions)
        mtmsr   r4                     // change MSR
#else   /* problems in rom2ram (see test-only in rom2ram!!!) */
        addi    r4,r0,0x0000          // dont set (!!!) ME bit (Machine
Exceptions)
        oris    r4,r4,0x0002          // set CE bit (Critical Exceptions)
        mtmsr   r4                     // change MSR
#endif
as you see it is same instruction.

It would be interesting to know why this happens.