diff mbox series

[net-next,v2,7/7] net: mvpp2: Consider NVMEM cells as possible MAC address source

Message ID 20221124111556.264647-8-miquel.raynal@bootlin.com (mailing list archive)
State Accepted
Commit 7a74c1265ab4340b0fd5223084151003ef4c394a
Delegated to: Netdev Maintainers
Headers show
Series Marvell nvmem mac addresses support | expand

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netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 6 this patch: 6
netdev/cc_maintainers warning 1 maintainers not CCed: linux@armlinux.org.uk
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
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netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 6 this patch: 6
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 13 lines checked
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netdev/source_inline success Was 0 now: 0

Commit Message

Miquel Raynal Nov. 24, 2022, 11:15 a.m. UTC
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
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 7 +++++++
 1 file changed, 7 insertions(+)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
index eb0fb8128096..12f0b5ad8cee 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -6104,6 +6104,13 @@  static void mvpp2_port_copy_mac_addr(struct net_device *dev, struct mvpp2 *priv,
 		}
 	}
 
+	/* Only valid on OF enabled platforms */
+	if (!of_get_mac_address_nvmem(to_of_node(fwnode), fw_mac_addr)) {
+		*mac_from = "nvmem cell";
+		eth_hw_addr_set(dev, fw_mac_addr);
+		return;
+	}
+
 	*mac_from = "random";
 	eth_hw_addr_random(dev);
 }