diff mbox

[4/4] drivers/net/fec: Don't mess with configured MAC addresses.

Message ID a6ba75577552abe8d5045434030c276d5f45779a.1300724245.git.LW@KARO-electronics.de
State Changes Requested, archived
Delegated to: David Miller
Headers show

Commit Message

Lothar Waßmann March 21, 2011, 4:37 p.m. UTC
The FEC driver currently uses the MAC address assigned to the first
interface incremented by one for the second interface.

Change this to be able to configure distinct MAC addresses via
platform_data.

Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
---
 drivers/net/fec.c |    9 ++-------
 1 files changed, 2 insertions(+), 7 deletions(-)

Comments

Shawn Guo March 22, 2011, 7:43 a.m. UTC | #1
On Mon, Mar 21, 2011 at 05:37:36PM +0100, Lothar Waßmann wrote:
> The FEC driver currently uses the MAC address assigned to the first
> interface incremented by one for the second interface.
> 
> Change this to be able to configure distinct MAC addresses via
> platform_data.
> 
> Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
> ---
>  drivers/net/fec.c |    9 ++-------
>  1 files changed, 2 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/net/fec.c b/drivers/net/fec.c
> index 3666524..9d89e99 100644
> --- a/drivers/net/fec.c
> +++ b/drivers/net/fec.c
> @@ -750,13 +750,12 @@ static void __inline__ fec_get_mac(struct net_device *ndev)
>  	/*
>  	 * 2) from flash or fuse (via platform data)
>  	 */
> +	if (pdata)
> +		memcpy(iap, pdata->mac, ETH_ALEN);
>  	if (!is_valid_ether_addr(iap)) {
>  #ifdef CONFIG_M5272
>  		if (FEC_FLASHMAC)
>  			iap = (unsigned char *)FEC_FLASHMAC;
> -#else
> -		if (pdata)
> -			memcpy(iap, pdata->mac, ETH_ALEN);
>  #endif
>  	}
>  
> @@ -772,10 +771,6 @@ static void __inline__ fec_get_mac(struct net_device *ndev)
>  	}
>  
>  	memcpy(ndev->dev_addr, iap, ETH_ALEN);
> -
> -	/* Adjust MAC if using macaddr */
> -	if (iap == macaddr)
> -		 ndev->dev_addr[ETH_ALEN-1] = macaddr[ETH_ALEN-1] + fep->pdev->id;
>  }
>  
>  /* ------------------------------------------------------------------------- */
> -- 
> 1.5.6.5
> 
> 
NAK.

The 'mac' was designed as an optional member of fec
platform_data, as some platforms may not be able to provide it. This
patch breaks the order of getting mac, and will not work on the
platform that does not provide an valid mac with either platform_data
or controller mac registers, even there may be one in the kernel
command line.

The existing code takes mac address from kernel command line as the
first choice, and only falls through on other options when it's
invalid/unavailable.  So an valid mac from  kernel command line will
always get fec work anyway.
Lothar Waßmann March 22, 2011, 7:49 a.m. UTC | #2
Hi,

Shawn Guo writes:
> On Mon, Mar 21, 2011 at 05:37:36PM +0100, Lothar Waßmann wrote:
> > The FEC driver currently uses the MAC address assigned to the first
> > interface incremented by one for the second interface.
> > 
> > Change this to be able to configure distinct MAC addresses via
> > platform_data.
> > 
> > Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
> > ---
> >  drivers/net/fec.c |    9 ++-------
> >  1 files changed, 2 insertions(+), 7 deletions(-)
> > 
> > diff --git a/drivers/net/fec.c b/drivers/net/fec.c
> > index 3666524..9d89e99 100644
> > --- a/drivers/net/fec.c
> > +++ b/drivers/net/fec.c
> > @@ -750,13 +750,12 @@ static void __inline__ fec_get_mac(struct net_device *ndev)
> >  	/*
> >  	 * 2) from flash or fuse (via platform data)
> >  	 */
> > +	if (pdata)
> > +		memcpy(iap, pdata->mac, ETH_ALEN);
> >  	if (!is_valid_ether_addr(iap)) {
> >  #ifdef CONFIG_M5272
> >  		if (FEC_FLASHMAC)
> >  			iap = (unsigned char *)FEC_FLASHMAC;
> > -#else
> > -		if (pdata)
> > -			memcpy(iap, pdata->mac, ETH_ALEN);
> >  #endif
> >  	}
> >  
> > @@ -772,10 +771,6 @@ static void __inline__ fec_get_mac(struct net_device *ndev)
> >  	}
> >  
> >  	memcpy(ndev->dev_addr, iap, ETH_ALEN);
> > -
> > -	/* Adjust MAC if using macaddr */
> > -	if (iap == macaddr)
> > -		 ndev->dev_addr[ETH_ALEN-1] = macaddr[ETH_ALEN-1] + fep->pdev->id;
> >  }
> >  
> >  /* ------------------------------------------------------------------------- */
> > -- 
> > 1.5.6.5
> > 
> > 
> NAK.
> 
> The 'mac' was designed as an optional member of fec
> platform_data, as some platforms may not be able to provide it. This
> patch breaks the order of getting mac, and will not work on the
> platform that does not provide an valid mac with either platform_data
> or controller mac registers, even there may be one in the kernel
> command line.
> 
> The existing code takes mac address from kernel command line as the
> first choice, and only falls through on other options when it's
> invalid/unavailable.  So an valid mac from  kernel command line will
> always get fec work anyway.
> 
The problem is that you can only assign one mac address on the kernel
cmdline and the second one will be derived from the first one.
And even if the MAC address is set via platform_data it will not be
used for the second interface.

IMO an ethernet driver has no business in inventing arbitrary MAC
addresses. Either the MAC address is supplied by the boot loader or
the platform code or it has to be assigned from userspace via
ifconfig.



Lothar Waßmann
Shawn Guo March 22, 2011, 8:55 a.m. UTC | #3
On Tue, Mar 22, 2011 at 08:49:41AM +0100, Lothar Waßmann wrote:
> Hi,
> 
> Shawn Guo writes:
> > On Mon, Mar 21, 2011 at 05:37:36PM +0100, Lothar Waßmann wrote:
> > > The FEC driver currently uses the MAC address assigned to the first
> > > interface incremented by one for the second interface.
> > > 
> > > Change this to be able to configure distinct MAC addresses via
> > > platform_data.
> > > 
> > > Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
> > > ---
> > >  drivers/net/fec.c |    9 ++-------
> > >  1 files changed, 2 insertions(+), 7 deletions(-)
> > > 
> > > diff --git a/drivers/net/fec.c b/drivers/net/fec.c
> > > index 3666524..9d89e99 100644
> > > --- a/drivers/net/fec.c
> > > +++ b/drivers/net/fec.c
> > > @@ -750,13 +750,12 @@ static void __inline__ fec_get_mac(struct net_device *ndev)
> > >  	/*
> > >  	 * 2) from flash or fuse (via platform data)
> > >  	 */
> > > +	if (pdata)
> > > +		memcpy(iap, pdata->mac, ETH_ALEN);
> > >  	if (!is_valid_ether_addr(iap)) {
> > >  #ifdef CONFIG_M5272
> > >  		if (FEC_FLASHMAC)
> > >  			iap = (unsigned char *)FEC_FLASHMAC;
> > > -#else
> > > -		if (pdata)
> > > -			memcpy(iap, pdata->mac, ETH_ALEN);
> > >  #endif
> > >  	}
> > >  
> > > @@ -772,10 +771,6 @@ static void __inline__ fec_get_mac(struct net_device *ndev)
> > >  	}
> > >  
> > >  	memcpy(ndev->dev_addr, iap, ETH_ALEN);
> > > -
> > > -	/* Adjust MAC if using macaddr */
> > > -	if (iap == macaddr)
> > > -		 ndev->dev_addr[ETH_ALEN-1] = macaddr[ETH_ALEN-1] + fep->pdev->id;
> > >  }
> > >  
> > >  /* ------------------------------------------------------------------------- */
> > > -- 
> > > 1.5.6.5
> > > 
> > > 
> > NAK.
> > 
> > The 'mac' was designed as an optional member of fec
> > platform_data, as some platforms may not be able to provide it. This
> > patch breaks the order of getting mac, and will not work on the
> > platform that does not provide an valid mac with either platform_data
> > or controller mac registers, even there may be one in the kernel
> > command line.
> > 
> > The existing code takes mac address from kernel command line as the
> > first choice, and only falls through on other options when it's
> > invalid/unavailable.  So an valid mac from  kernel command line will
> > always get fec work anyway.
> > 
> The problem is that you can only assign one mac address on the kernel
> cmdline and the second one will be derived from the first one.
> And even if the MAC address is set via platform_data it will not be
> used for the second interface.
> 
Yes, these are problems.  But we can fix them like the following while
still make fec0 work with fec.macaddr.  This is useful on the platform
that neither platform code nor boot loader gives an valid mac address.

@@ -721,7 +721,7 @@ static void __inline__ fec_get_mac(struct net_device *ndev)
 {
        struct fec_enet_private *fep = netdev_priv(ndev);
        struct fec_platform_data *pdata = fep->pdev->dev.platform_data;
-       unsigned char *iap, tmpaddr[ETH_ALEN];
+       unsigned char iap[ETH_ALEN], tmpaddr[ETH_ALEN];

        /*
         * try to get mac address in following order:
@@ -729,7 +729,10 @@ static void __inline__ fec_get_mac(struct net_device *ndev)
         * 1) module parameter via kernel command line in form
         *    fec.macaddr=0x00,0x04,0x9f,0x01,0x30,0xe0
         */
-       iap = macaddr;
+       if (fep->pdev->id == 0)
+               memcpy(iap, macaddr, ETH_ALEN);
+       else
+               memset(iap, 0, ETH_ALEN);

        /*
         * 2) from flash or fuse (via platform data)
@@ -752,14 +755,10 @@ static void __inline__ fec_get_mac(struct net_device *ndev)
                        be32_to_cpu(readl(fep->hwp + FEC_ADDR_LOW));
                *((unsigned short *) &tmpaddr[4]) =
                        be16_to_cpu(readl(fep->hwp + FEC_ADDR_HIGH) >> 16);
-               iap = &tmpaddr[0];
+               memcpy(iap, tmpaddr, ETH_ALEN);
        }

        memcpy(ndev->dev_addr, iap, ETH_ALEN);
-
-       /* Adjust MAC if using macaddr */
-       if (iap == macaddr)
-                ndev->dev_addr[ETH_ALEN-1] = macaddr[ETH_ALEN-1] + fep->pdev->id;
 }

> IMO an ethernet driver has no business in inventing arbitrary MAC
> addresses. Either the MAC address is supplied by the boot loader or
> the platform code or it has to be assigned from userspace via
> ifconfig.
> 
ifconfig will not be an option if we need to mount nfs as rootfs.
So we at lease need to have kernel command line for fec0 mac address
for the last chance, if neither platform data nor boot loader provides
mac address.  And let ifconfig provide mac for fec1 from user space.
diff mbox

Patch

diff --git a/drivers/net/fec.c b/drivers/net/fec.c
index 3666524..9d89e99 100644
--- a/drivers/net/fec.c
+++ b/drivers/net/fec.c
@@ -750,13 +750,12 @@  static void __inline__ fec_get_mac(struct net_device *ndev)
 	/*
 	 * 2) from flash or fuse (via platform data)
 	 */
+	if (pdata)
+		memcpy(iap, pdata->mac, ETH_ALEN);
 	if (!is_valid_ether_addr(iap)) {
 #ifdef CONFIG_M5272
 		if (FEC_FLASHMAC)
 			iap = (unsigned char *)FEC_FLASHMAC;
-#else
-		if (pdata)
-			memcpy(iap, pdata->mac, ETH_ALEN);
 #endif
 	}
 
@@ -772,10 +771,6 @@  static void __inline__ fec_get_mac(struct net_device *ndev)
 	}
 
 	memcpy(ndev->dev_addr, iap, ETH_ALEN);
-
-	/* Adjust MAC if using macaddr */
-	if (iap == macaddr)
-		 ndev->dev_addr[ETH_ALEN-1] = macaddr[ETH_ALEN-1] + fep->pdev->id;
 }
 
 /* ------------------------------------------------------------------------- */