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Like to know what the maximum size is I can the current 8.4GB IDE
harddisk with in my Sun Ultra 5.

Marc wrote:

> Like to know what the maximum size is I can the current 8.4GB IDE
> harddisk with in my Sun Ultra 5.

From the hardware side the max. size of an IDE disk on the U5/10 is 128GB.
That's the max. size the OpenFirmware recognises for booting. You can use
bigger disks as secondary disk, though, they'll be useable as soon as the OS
is up and running...

However, there also are disk size limitations within older Solaris
Releases...

Benjamin

"Benjamin Gawert" <bgawert@gmx.de> writes:

>From the hardware side the max. size of an IDE disk on the U5/10 is 128GB.
>That's the max. size the OpenFirmware recognises for booting. You can use
>bigger disks as secondary disk, though, they'll be useable as soon as the OS
>is up and running...

Not quite, the IDE controller is limited to 128GB disks on
the U5/U10.

Casper
--
Expressed in this posting are my opinions. They are in no way related
to opinions held by my employer, Sun Microsystems.
Statements on Sun products included here are not gospel and may
be fiction rather than truth.

Casper H.S. Dik wrote:

> Not quite, the IDE controller is limited to 128GB disks on
> the U5/U10.

IDE controllers are _not_ limited to any disk size, that's BS. This is only
a firmware issue...

If it really would be a firmware issue how comes that the 200GB disk in my
U10 works as a secondary drive with full capacity?

Benjamin

"Benjamin Gawert" <bgawert@gmx.de> writes:

>Casper H.S. Dik wrote:

>> Not quite, the IDE controller is limited to 128GB disks on
>> the U5/U10.

>IDE controllers are _not_ limited to any disk size, that's BS. This is only
>a firmware issue...

No it is not; supposedly, the IDE controllers in the U5/U10
cannot do LBA mode and DMA at the same time *and* supposedly the
SPARC drivers does not support addressing over 128GB either.

>If it really would be a firmware issue how comes that the 200GB disk in my
>U10 works as a secondary drive with full capacity?


That suprises me a lot because for the onboard controller, there are
two reasons why it shouldn't work.

Casper
--
Expressed in this posting are my opinions. They are in no way related
to opinions held by my employer, Sun Microsystems.
Statements on Sun products included here are not gospel and may
be fiction rather than truth.

Casper H.S. Dik wrote:

>> IDE controllers are _not_ limited to any disk size, that's BS. This
>> is only a firmware issue...
>
> No it is not; supposedly, the IDE controllers in the U5/U10
> cannot do LBA mode and DMA at the same time *and* supposedly the
> SPARC drivers does not support addressing over 128GB either.

You obviously have no clue about what LBA and DMA is.

LBA ("Large Block Addressing" or "Lgical Block Addressing") is a adressing
is a addressing scheme to convert the Cylinders, heads and sectors a disk
uses for addressing into a number of available blocks, thus overcoming the
common limitations of a PC BIOS. This has _nothing_ to do with the
controller IC but is solely a firmware (BIOS) issue.

For a closer description of what LBA does have a look here:
<http://www.pcguide.com/ref/hdd/bios/modesLBA-c.html>

The problem with the U6/10 is that the OpenFirmware uses only a 28bit
addressing scheme which limits the addressable disk size to 128GB (or 137GB,
depending on how big a GB is).

DMA ("Direct Memory Access") simply means that the IDE controller can push
the data direct into the computers' memory instead of having to use the cpu
for that (Polling, used with the old PIO modes). This indeed is dependent
from the firmware _and_ from the controller but has absolutely _nothing_ to
do with the disk size. You can use 300GB disk in PIO mode if You want, it
will be slow like hell and cause a lot of CPU load but it will work fine.

>> If it really would be a firmware issue how comes that the 200GB disk
>> in my U10 works as a secondary drive with full capacity?
>
>
> That suprises me a lot because for the onboard controller, there are
> two reasons why it shouldn't work.

No, there aren't. As I said before the 128GB disk size limit is only a
OpenFirmware limitation (28Bit adressing scheme). As soon as the OS is
loaded a driver takes control over the IDE controller, and from this time
for a secondary drive You're limited only to the disk size addressable by
that driver. Sadly, the Solaris drivers take the disk size reports from OFw
when loeading, but long ago I somehwere found a description how to make the
driver requesting the disk size from the disk rather from OFw. I just
followed the description and it worked. The disk now contains two 80Gb /home
and /home2 directories and a 40GB ftp directory.

I can check if I still have the link.

Benjamin

Benjamin Gawert wrote on Sunday 18 July 2004 10:38 :
> Sadly, the Solaris drivers take the disk size reports from
> OFw when loeading, but long ago I somehwere found a description how to
> make the driver requesting the disk size from the disk rather from OFw. I
> just followed the description and it worked. The disk now contains two
> 80Gb /home and /home2 directories and a 40GB ftp directory.
>
> I can check if I still have the link.

Please do. This "I can use very large (i.e. > 137 GB) IDE non-boot disks"
is the most interesting bit in the perpetual "How large can U5/10 IDE
disks be" threads for a long time.

Torsten Kirschner wrote:

>> I can check if I still have the link.
>
> Please do. This "I can use very large (i.e. > 137 GB) IDE non-boot
> disks" is the most interesting bit in the perpetual "How large can
> U5/10 IDE disks be" threads for a long time.

I'll do that when I find some free time. Unfortunately I have to go through
my old backups as the link isn't on my current setup anymore. And since my
U10 is mostly collecting dust I didn't care that much for this issue and
thought that other people already found that out, too.

Benjamin, currently removing the 200GB brick from the U10 to be used in a
different computer

"Benjamin Gawert" <bgawert@gmx.de> writes:

>DMA ("Direct Memory Access") simply means that the IDE controller can push
>the data direct into the computers' memory instead of having to use the cpu
>for that (Polling, used with the old PIO modes). This indeed is dependent
>from the firmware _and_ from the controller but has absolutely _nothing_ to
>do with the disk size. You can use 300GB disk in PIO mode if You want, it
>will be slow like hell and cause a lot of CPU load but it will work fine.

It's not when you take into account how broken hardware can be;
the specific IDE controller chips in the U10/U5 cannot support 48bits
LBA in DMA mode, only 28 bits LBA (they can do 48 bits LBA but only
when using PIO)

The IDE *driver* on SPARC only does 28 bit LBA; it doesn't know
about 48 bit LBA.

>No, there aren't. As I said before the 128GB disk size limit is only a
>OpenFirmware limitation (28Bit adressing scheme). As soon as the OS is
>loaded a driver takes control over the IDE controller, and from this time
>for a secondary drive You're limited only to the disk size addressable by
>that driver. Sadly, the Solaris drivers take the disk size reports from OFw
>when loeading, but long ago I somehwere found a description how to make the
>driver requesting the disk size from the disk rather from OFw. I just
>followed the description and it worked. The disk now contains two 80Gb /home
>and /home2 directories and a 40GB ftp directory.

Well, the bug report about only support 28 bit LBA is still open
and mentions hardware limitations of the SPARC IDE controller chips.

So I'm very curious why it would work for you.

Casper

Benjamin Gawert wrote:

> Torsten Kirschner wrote:
>
>
>>>I can check if I still have the link.
>>
>>Please do. This "I can use very large (i.e. > 137 GB) IDE non-boot
>>disks" is the most interesting bit in the perpetual "How large can
>>U5/10 IDE disks be" threads for a long time.
>
>
> I'll do that when I find some free time. Unfortunately I have to go through
> my old backups as the link isn't on my current setup anymore. And since my
> U10 is mostly collecting dust I didn't care that much for this issue and
> thought that other people already found that out, too.
>
> Benjamin, currently removing the 200GB brick from the U10 to be used in a
> different computer
>
>

On a related note, I'd like to find a way to use IDE disks on an AXi
based machine, which doesn't have the IDE stuff in the OBP at all.
It seems to me the patch you describe that allows a disk driver to
work independently of the OBP ought to also allow what I want to do.

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