[U-Boot] OMAP DIE_ID

[U-Boot] OMAP DIE_ID

[Frederik Kriewitz]

I'm a bit confused about the u-boot code which reads the OMAP die id.

[U-Boot] OMAP DIE_ID

[Dirk Behme]

Frederik Kriewitz wrote:
> I'm a bit confused about the u-boot code which reads the OMAP die id.
> 
>>From the OMAP TRM:
> CONTROL.CONTROL_DIE_ID[127:0]
> Address: 0x4830A218
> Size: 128
> 
> u-boot code: http://gitorious.org/u-boot-omap3/mainline/blobs/master/cpu/arm_cortexa8/omap3/sys_info.c#line44
> 
> result: Die ID #: 04ba0054 00000020 0401463b 0401c214
> Memory Dump: 4830a218: 0401c214 0401463b 00000020 04ba0054
> 
> Shouldn't u-boot read/show the die id the other way around (just as in
> the memory dump)?
> 
> Please just tell me that I'm wrong :)

I wouldn't talk about right or wrong here ;) Most probably this is 
just personal taste.

First, short summary about what we are talking:

u32 die_id_0;		/* 0x18 */
u32 die_id_1;		/* 0x1C */
u32 die_id_2;		/* 0x20 */
u32 die_id_3;		/* 0x24 */

id[3] = readl(&id_base->die_id_0);
id[2] = readl(&id_base->die_id_1);
id[1] = readl(&id_base->die_id_2);
id[0] = readl(&id_base->die_id_3);
sprintf(die_id, "%08x%08x%08x%08x", id[0], id[1], id[2], id[3]);

 From memory dump point of view, using above example, this is

4830a218: 0401c214  CONTROL_DIE_ID[31:0]
4830a21C: 0401463b  CONTROL_DIE_ID[63:32]
4830a220: 00000020 CONTROL_DIE_ID[95:64]
4830a224: 04ba0054  CONTROL_DIE_ID[127:96]

So we are printing

Die ID #: DIE_ID[127:96] DIE_ID[95:64] DIE_ID[63:32] DIE_ID[31:0]

as a 128 bit value with lowest value right and highest value left.

Is this correct?

At least, this is what I think was intended ;)

Best regards

Dirk

[U-Boot] OMAP DIE_ID

[Jean-Christophe PLAGNIOL-VILLARD]

On 16:24 Fri 14 Aug     , Frederik Kriewitz wrote:
> I'm a bit confused about the u-boot code which reads the OMAP die id.
> 
> >From the OMAP TRM:
> CONTROL.CONTROL_DIE_ID[127:0]
> Address: 0x4830A218
> Size: 128
> 
> u-boot code: http://gitorious.org/u-boot-omap3/mainline/blobs/master/cpu/arm_cortexa8/omap3/sys_info.c#line44
> 
> result: Die ID #: 04ba0054 00000020 0401463b 0401c214
> Memory Dump: 4830a218: 0401c214 0401463b 00000020 04ba0054
> 
> Shouldn't u-boot read/show the die id the other way around (just as in
> the memory dump)?
> 
> Please just tell me that I'm wrong :)
Honnesty it's not really important the order except you have a special need
it's really a personnal preference

NB: until someone give us a good reason to change we will keep it this way

Best Regards,
J.

[U-Boot] OMAP DIE_ID

[Frederik Kriewitz]

On Sat, Aug 15, 2009 at 4:35 PM, Jean-Christophe
PLAGNIOL-VILLARD<plagnioj@jcrosoft.com> wrote:
> Honnesty it's not really important the order except you have a special need
> it's really a personnal preference

I intent to use some bytes of the die id as MAC address. So I'm
interested in the bytes which change often.

[U-Boot] OMAP DIE_ID

[Jean-Christophe PLAGNIOL-VILLARD]

On 17:02 Sat 15 Aug     , Frederik Kriewitz wrote:
> On Sat, Aug 15, 2009 at 4:35 PM, Jean-Christophe
> PLAGNIOL-VILLARD<plagnioj@jcrosoft.com> wrote:
> > Honnesty it's not really important the order except you have a special need
> > it's really a personnal preference
> 
> I intent to use some bytes of the die id as MAC address. So I'm
> interested in the bytes which change often.
for private mac address or public?

for public you may need to remember that you are supposed to trac all of them
and do not loose any of them if you want to be able to buy a new lot of mac
address

IIRC the term of sell

Best Regards,
J.

[U-Boot] OMAP DIE_ID

[Frederik Kriewitz]

On Sat, Aug 15, 2009 at 6:12 PM, Jean-Christophe
PLAGNIOL-VILLARD<plagnioj@jcrosoft.com> wrote:
>> I intent to use some bytes of the die id as MAC address. So I'm
>> interested in the bytes which change often.
> for private mac address or public?
>
> for public you may need to remember that you are supposed to trac all of them
> and do not loose any of them if you want to be able to buy a new lot of mac
> address

private of course. I didn't develop the hardware.