[PATCHv2] net: uclass: Save ethernet MAC address when generated

[PATCHv2] net: uclass: Save ethernet MAC address when generated

[Tom Rini]

From: Michal Simek <michal.simek@xilinx.com>

When MAC address is randomly generated it should be also saved to
variables. This step is there when MAC address is passed via pdata but not
when it is randomly generated.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>
[trini: Update Kconfig, handle legacy networking case as well]
Signed-off-by: Tom Rini <trini@konsulko.com>
---
Changes in v2:
- Update Kconfig help text to reflect this change.
- Update the legacy path to match.
---
 net/Kconfig      | 6 +++---
 net/eth-uclass.c | 2 ++
 net/eth_legacy.c | 2 ++
 3 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/net/Kconfig b/net/Kconfig
index 7a2d14501881..20a36156a01f 100644
--- a/net/Kconfig
+++ b/net/Kconfig
@@ -28,9 +28,9 @@ config NET_RANDOM_ETHADDR
 	bool "Random ethaddr if unset"
 	help
 	  Selecting this will allow the Ethernet interface to function
-	  even when the ethaddr variable for that interface is unset.
-	  A new MAC address will be generated on every boot and it will
-	  not be added to the environment.
+	  even when the ethaddr variable for that interface is unset by
+	  generating a new MAC address in the locally administered address
+	  space and setting the appropriate environment variable.
 
 config NETCONSOLE
 	bool "NetConsole support"
diff --git a/net/eth-uclass.c b/net/eth-uclass.c
index 0da0e85be031..58c308f33276 100644
--- a/net/eth-uclass.c
+++ b/net/eth-uclass.c
@@ -583,6 +583,8 @@ static int eth_post_probe(struct udevice *dev)
 		net_random_ethaddr(pdata->enetaddr);
 		printf("\nWarning: %s (eth%d) using random MAC address - %pM\n",
 		       dev->name, dev_seq(dev), pdata->enetaddr);
+		eth_env_set_enetaddr_by_index("eth", dev_seq(dev),
+					      pdata->enetaddr);
 #else
 		printf("\nError: %s address not set.\n",
 		       dev->name);
diff --git a/net/eth_legacy.c b/net/eth_legacy.c
index f383ccce0b92..e7f53b958b2e 100644
--- a/net/eth_legacy.c
+++ b/net/eth_legacy.c
@@ -164,6 +164,8 @@ int eth_write_hwaddr(struct eth_device *dev, const char *base_name,
 		net_random_ethaddr(dev->enetaddr);
 		printf("\nWarning: %s (eth%d) using random MAC address - %pM\n",
 		       dev->name, eth_number, dev->enetaddr);
+		eth_env_set_enetaddr_by_index("eth", dev_seq(dev),
+					      pdata->enetaddr);
 #else
 		printf("\nError: %s address not set.\n",
 		       dev->name);
-- 
2.25.1

Re: [PATCHv2] net: uclass: Save ethernet MAC address when generated

[Wolfgang Denk]

Dear Tom,

In message <20211120155358.376540-1-trini@konsulko.com> you wrote:
>
> When MAC address is randomly generated it should be also saved to
> variables. This step is there when MAC address is passed via pdata but not
> when it is randomly generated.

"saved to variables" ? Which variables? In C code?  In the
environment?

This is not clear here.

>  	  Selecting this will allow the Ethernet interface to function
> -	  even when the ethaddr variable for that interface is unset.
> -	  A new MAC address will be generated on every boot and it will
> -	  not be added to the environment.
> +	  even when the ethaddr variable for that interface is unset by
> +	  generating a new MAC address in the locally administered address
> +	  space and setting the appropriate environment variable.

Same here: "ethaddr variable" - I guess this refers to the
environment variable?  Then we should write that.

Hmmm: "when the ethaddr variable ... is unset by generating ... and
setting the appropriate environment variable."  this is misleading,
as the "ethaddr variable" is not unset by setting the env var.

Suggestion:

	Selecting this will allow the Ethernet interface to function
	even when the ethaddr variable for that interface is unset.
	In this case, a random MAC address in the locally
	administered address space is generated. It will be saved to
	the appropriate environment variable, too.

Best regards,

Wolfgang Denk

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