[U-Boot-Users] [ANNOUNCE] u-boot-ptx-20030213-1

[U-Boot-Users] [ANNOUNCE] u-boot-ptx-20030213-1

[Robert Schwebel]

Hi, 

on http://www.pengutronix.de/software/u-boot_en.html you'll find our
latest u-boot patch, mostly for PXA250 and Cogent CSB226. It was made
against current CVS, so be quick if you want to apply it ;-) 

Most of the patch was already sent to Wolfgang in a more documented way,
so this is mostly meant as something for people who actively develop for
the PXA plattform.

Comments are welcome...  

Robert
-- 
 Dipl.-Ing. Robert Schwebel | http://www.pengutronix.de
 Pengutronix - Linux Solutions for Science and Industry
   Braunschweiger Str. 79,  31134 Hildesheim, Germany
   Handelsregister:  Amtsgericht Hildesheim, HRA 2686
    Phone: +49-5121-28619-0 |  Fax: +49-5121-28619-4

[U-Boot-Users] [ANNOUNCE] u-boot-ptx-20030213-1

[Geir Thomassen]

Any chance of getting this into CVS ?

[U-Boot-Users] [ANNOUNCE] u-boot-ptx-20030213-1

[Geir Thomassen]

 From your patch (memsetup.S, various versions ..)

/* Step 4f: Trigger a number (usually 8) refresh cycles by     */
/*          attempting non-burst read or write accesses to disabled */
/*          SDRAM, as commonly specified in the power up sequence   */
/*          documented in SDRAM data sheets. The address(es) used   */
/*          for this purpose must not be cacheable.                 */

        ldr     r3,     =CFG_DRAM_BASE
        str     r2,     [r3]
        str     r2,     [r3]
        str     r2,     [r3]
        str     r2,     [r3]
        str     r2,     [r3]
        str     r2,     [r3]
        str     r2,     [r3]
        str     r2,     [r3]


There should 9 writes, since the first write doesn't trigger a refresh 
cycle on PXA250. See Intel? PXA250 and PXA210 Processors Specification 
Update, Jan 2003, Errata #116, page 30.


.rept 9
    str     r2, [r2]
.endr


-- 
Geir

[U-Boot-Users] [ANNOUNCE] u-boot-ptx-20030213-1

[Robert Schwebel]

On Thu, Feb 13, 2003 at 10:20:42AM +0100, Geir Thomassen wrote:
> Any chance of getting this into CVS ?

You should be a little bit patient, Wolfgang has just moved office. 

Robert
-- 
 Dipl.-Ing. Robert Schwebel | http://www.pengutronix.de
 Pengutronix - Linux Solutions for Science and Industry
   Braunschweiger Str. 79,  31134 Hildesheim, Germany
   Handelsregister:  Amtsgericht Hildesheim, HRA 2686
    Phone: +49-5121-28619-0 |  Fax: +49-5121-28619-4

[U-Boot-Users] [ANNOUNCE] u-boot-ptx-20030213-1

[Robert Schwebel]

On Thu, Feb 13, 2003 at 10:28:23AM +0100, Geir Thomassen wrote:
> There should 9 writes, since the first write doesn't trigger a refresh
> cycle on PXA250. See Intel? PXA250 and PXA210 Processors Specification
> Update, Jan 2003, Errata #116, page 30.

Thanks, will be in the next patch. 

Robert 
-- 
 Dipl.-Ing. Robert Schwebel | http://www.pengutronix.de
 Pengutronix - Linux Solutions for Science and Industry
   Braunschweiger Str. 79,  31134 Hildesheim, Germany
   Handelsregister:  Amtsgericht Hildesheim, HRA 2686
    Phone: +49-5121-28619-0 |  Fax: +49-5121-28619-4

[U-Boot-Users] [ANNOUNCE] u-boot-ptx-20030213-1

[Wolfgang Denk]

In message <3E4B636A.9030202@in.fer.no> you wrote:
> Any chance of getting this into CVS ?

Yes, of course: it's in my queue, but it seems I won't find time  for
it for another week (until after the Embedded World).

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
See us @ Embedded World, Nuremberg, Feb 18-20, Hall 12.0 Booth 12-442

[U-Boot-Users] [ANNOUNCE] u-boot-ptx-20030213-1

[Geir Thomassen]

Robert Schwebel wrote:
> 
> Comments are welcome...  
> 

in cpu/xscale/start.S you do:

/* test if we run from flash or RAM - RAM/BDI: don't set cpuspeed   */
/* FIXME: is the criterium used here only valid for PXA25X?         */
    mov     r0, pc
    and     r0, r0, #0xF0000000 /* RAM is at 0xa0000000-0xafffffff */
    subs    r0, r0, #0xa0000000
    beq     setspeed_done

    mov     r0, #2
    mcr     p14, 0, r0, c6, c0, 0
setspeed_done:


Why? I can trace trough the CPU speed setting code without any trouble 
with a BDI, and I don't understand why there should be any problems 
doing so. Disabeling the CPU speed setting code without skipping the 
SDRAM init code at the same time might actually get you into other 
problems since the refresh periode of the SDRAM might be too long. 
Jumping over the SDRAM init is a very good idea, since the code is 
running from the SDRAM that the code is initializing. One important step 
of the init sequence is to disable the SDRAM.

-- 
Geir

[U-Boot-Users] [ANNOUNCE] u-boot-ptx-20030213-1

[Robert Schwebel]

On Thu, Feb 13, 2003 at 09:42:51PM +0100, Geir Thomassen wrote:
> in cpu/xscale/start.S you do:
> 
> /* test if we run from flash or RAM - RAM/BDI: don't set cpuspeed   */
> /* FIXME: is the criterium used here only valid for PXA25X?         */
>    mov     r0, pc
>    and     r0, r0, #0xF0000000 /* RAM is at 0xa0000000-0xafffffff */
>    subs    r0, r0, #0xa0000000
>    beq     setspeed_done
> 
>    mov     r0, #2
>    mcr     p14, 0, r0, c6, c0, 0
> setspeed_done:
> 
> 
> Why? I can trace trough the CPU speed setting code without any trouble 
> with a BDI, and I don't understand why there should be any problems 
> doing so. Disabeling the CPU speed setting code without skipping the 
> SDRAM init code at the same time might actually get you into other 
> problems since the refresh periode of the SDRAM might be too long. 
> Jumping over the SDRAM init is a very good idea, since the code is 
> running from the SDRAM that the code is initializing. One important step 
> of the init sequence is to disable the SDRAM.

The code in question was added last week and I removed it today from my
local tree :-) 

The problem is that there is a bug in at least some hardware revisions
of the PXA which in my case lets the debug handler disappear from the
mini instruction cache once you access CP14 to switch the frequency.
I've discussed this with the Abatron guys for some weeks now and they
today have sent me a new firmware which works around the bug. It will be
available officially in some days. However, as I'm now able to run the
code in the debugger again the above code can be forgotten - I will not
send it to Wolfgang officially. 

Robert
-- 
 Dipl.-Ing. Robert Schwebel | http://www.pengutronix.de
 Pengutronix - Linux Solutions for Science and Industry
   Braunschweiger Str. 79,  31134 Hildesheim, Germany
   Handelsregister:  Amtsgericht Hildesheim, HRA 2686
    Phone: +49-5121-28619-0 |  Fax: +49-5121-28619-4