Hi Marcin, mw@xxxxxxxxxxxx wrote on Mon, 21 Nov 2022 15:46:44 +0100: > pon., 21 lis 2022 o 10:29 Miquel Raynal <miquel.raynal@xxxxxxxxxxx> napisał(a): > > > > Hi Marcin, > > > > mw@xxxxxxxxxxxx wrote on Sat, 19 Nov 2022 09:18:34 +0100: > > > > > Hi Miquel, > > > > > > > > > czw., 17 lis 2022 o 22:56 Miquel Raynal <miquel.raynal@xxxxxxxxxxx> napisał(a): > > > > > > > > The ONIE standard describes the organization of tlv (type-length-value) > > > > arrays commonly stored within NVMEM devices on common networking > > > > hardware. > > > > > > > > Several drivers already make use of NVMEM cells for purposes like > > > > retrieving a default MAC address provided by the manufacturer. > > > > > > > > What made ONIE tables unusable so far was the fact that the information > > > > where "dynamically" located within the table depending on the > > > > manufacturer wishes, while Linux NVMEM support only allowed statically > > > > defined NVMEM cells. Fortunately, this limitation was eventually tackled > > > > with the introduction of discoverable cells through the use of NVMEM > > > > layouts, making it possible to extract and consistently use the content > > > > of tables like ONIE's tlv arrays. > > > > > > > > Parsing this table at runtime in order to get various information is now > > > > possible. So, because many Marvell networking switches already follow > > > > this standard, let's consider using NVMEM cells as a new valid source of > > > > information when looking for a base MAC address, which is one of the > > > > primary uses of these new fields. Indeed, manufacturers following the > > > > ONIE standard are encouraged to provide a default MAC address there, so > > > > let's eventually use it if no other MAC address has been found using the > > > > existing methods. > > > > > > > > Link: https://opencomputeproject.github.io/onie/design-spec/hw_requirements.html > > > > > > Thanks for the patch. Did you manage to test in on a real HW? I am curious about > > > > Yes, I have a Replica switch on which the commercial ports use the > > replica PCI IP while the config "OOB" port is running with mvpp2: > > [ 16.737759] mvpp2 f2000000.ethernet eth52: Using nvmem cell mac address 18:be:92:13:9a:00 > > > > Nice. Do you have a DT snippet that can possibly be shared? I'd like > to recreate this locally and eventually leverage EDK2 firmware to > expose that. Yes of course, the DT is public on Sartura's Github, but here is the exact file I used showing the diff cleaning the Armada 7040 TN48M DT eeprom description and its use as an nvmem-cell provider): https://github.com/miquelraynal/linux/commit/230ee68728799454e2f07f61792e11724e731d6d > > > > > Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx> > > > > --- > > > > drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 6 ++++++ > > > > 1 file changed, 6 insertions(+) > > > > > > > > diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c > > > > index eb0fb8128096..7c8c323f4411 100644 > > > > --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c > > > > +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c > > > > @@ -6104,6 +6104,12 @@ static void mvpp2_port_copy_mac_addr(struct net_device *dev, struct mvpp2 *priv, > > > > } > > > > } > > > > > > > > + if (!of_get_mac_address(to_of_node(fwnode), hw_mac_addr)) { > > > > > > Unfortunately, nvmem cells seem to be not supported with ACPI yet, so > > > we cannot extend fwnode_get_mac_address - I think it should be, > > > however, an end solution. > > > > Agreed. > > > > > As of now, I'd prefer to use of_get_mac_addr_nvmem directly, to avoid > > > parsing the DT again (after fwnode_get_mac_address) and relying > > > implicitly on falling back to nvmem stuff (currently, without any > > > comment it is not obvious). > > > > I did not do that in the first place because of_get_mac_addr_nvmem() > > was not exported, but I agree it would be the cleanest (and quickest) > > approach, so I'll attempt to export the function first, and then use it > > directly from the driver. > > > > That would be great, thank you. Please add one-comment in the > mvpp2_main.c, that this is valid for now only in DT world. Ack. Thanks, Miquèl
