Hi,
On 24-03-15 00:12, Rob Herring wrote:
On Mon, Mar 23, 2015 at 6:30 AM, Hans de Goede hdegoede@redhat.com wrote:
Hi,
On 22-03-15 22:01, Rob Herring wrote:
<snip>
There is already "serial-number" (a string) which exists for OpenFirmware. Also, "copyright" corresponds to vendor/manufacturer string. Both of these are supported by lshw already.
Ok, so if I understand you correctly then you're saying that we should set a "serial-number" string property at the dt root level and that this may contain pretty much anything, e.g. in the sunxi case the full 128 bit SID in hex.
Right.
Is the use of the "serial-number" string property already documented somewhere? If not I'll submit a kernel patch to document it.
Not that I'm aware of. It is something that predates our documentation requirements. It could be in OpenFirmware specs. Documenting it in the DT bindings does not hurt.
Ok.
And for older kernels we should not set any serial atag (u-boot always sets it, so this leaves it at 0) and old kernel users are out of luck wrt getting to the serial ?
If there is sufficient reason to support this on old kernels you could.
One problem with supporting this for older kernels is that if a non 0 serial gets shown in /proc/cpuinfo with older atag booted kernels, we should really show the same number in /proc/cpuinfo which means adding code to the kernel to get the devicetree "serial-number" string property and somehow put that into the 64 bits which we have in /proc/cpuinfo, but given that the "serial-number" string could be hex or decimal or what ever and > 64 bits that will likely require a platform specific solution. All doable, but the question then becomes is this worth the effort ?
Regards,
Hans