Re: [RFC PATCH net-next 6/7] net: sunhme: Consolidate mac address initialization

[Simon Horman]

On Wed, Feb 22, 2023 at 04:03:54PM -0500, Sean Anderson wrote:
> The mac address initialization is braodly the same between PCI and SBUS,
> and one was clearly copied from the other. Consolidate them. We still have
> to have some ifdefs because pci_(un)map_rom is only implemented for PCI,
> and idprom is only implemented for SPARC.
> 
> Signed-off-by: Sean Anderson <seanga2@xxxxxxxxx>

Overall this looks to correctly move code around as suggest.
Some minor nits and questions inline.

> ---
> 
>  drivers/net/ethernet/sun/sunhme.c | 284 ++++++++++++++----------------
>  1 file changed, 135 insertions(+), 149 deletions(-)
> 
> diff --git a/drivers/net/ethernet/sun/sunhme.c b/drivers/net/ethernet/sun/sunhme.c
> index 75993834729a..9b55adbe61df 100644
> --- a/drivers/net/ethernet/sun/sunhme.c
> +++ b/drivers/net/ethernet/sun/sunhme.c
> @@ -34,6 +34,7 @@
>  #include <linux/mm.h>
>  #include <linux/module.h>
>  #include <linux/netdevice.h>
> +#include <linux/of.h>
>  #include <linux/random.h>
>  #include <linux/skbuff.h>
>  #include <linux/slab.h>
> @@ -47,7 +48,6 @@
>  #include <asm/oplib.h>
>  #include <asm/prom.h>
>  #include <linux/of_device.h>
> -#include <linux/of.h>
>  #endif
>  #include <linux/uaccess.h>
>  

nit: The above hunks don't seem related to the rest of this patch.

> @@ -2313,6 +2313,133 @@ static const struct net_device_ops hme_netdev_ops = {
>  	.ndo_validate_addr	= eth_validate_addr,
>  };
>  
> +#ifdef CONFIG_PCI
> +static int is_quattro_p(struct pci_dev *pdev)

nit: I know you are moving code around here,
     and likewise for many of my other comments.
     But I think bool would be a better return type for this function.

> +{
> +	struct pci_dev *busdev = pdev->bus->self;
> +	struct pci_dev *this_pdev;
> +	int n_hmes;
> +
> +	if (!busdev || busdev->vendor != PCI_VENDOR_ID_DEC ||
> +	    busdev->device != PCI_DEVICE_ID_DEC_21153)
> +		return 0;
> +
> +	n_hmes = 0;
> +	list_for_each_entry(this_pdev, &pdev->bus->devices, bus_list) {
> +		if (this_pdev->vendor == PCI_VENDOR_ID_SUN &&
> +		    this_pdev->device == PCI_DEVICE_ID_SUN_HAPPYMEAL)
> +			n_hmes++;
> +	}
> +
> +	if (n_hmes != 4)
> +		return 0;
> +
> +	return 1;
> +}
> +
> +/* Fetch MAC address from vital product data of PCI ROM. */
> +static int find_eth_addr_in_vpd(void __iomem *rom_base, int len, int index, unsigned char *dev_addr)

nit: At some point it might be better
     to update this function to return 0 on success and
     an error otherwise.

> +{
> +	int this_offset;
> +
> +	for (this_offset = 0x20; this_offset < len; this_offset++) {
> +		void __iomem *p = rom_base + this_offset;
> +
> +		if (readb(p + 0) != 0x90 ||
> +		    readb(p + 1) != 0x00 ||
> +		    readb(p + 2) != 0x09 ||
> +		    readb(p + 3) != 0x4e ||
> +		    readb(p + 4) != 0x41 ||
> +		    readb(p + 5) != 0x06)
> +			continue;
> +
> +		this_offset += 6;
> +		p += 6;
> +
> +		if (index == 0) {
> +			int i;
> +
> +			for (i = 0; i < 6; i++)

nit: This could be,

			for (int i = 0; i < 6; i++)

> +				dev_addr[i] = readb(p + i);
> +			return 1;
> +		}
> +		index--;
> +	}

nit: blank line

> +	return 0;
> +}
> +
> +static void __maybe_unused get_hme_mac_nonsparc(struct pci_dev *pdev,
> +						unsigned char *dev_addr)
> +{
> +	size_t size;
> +	void __iomem *p = pci_map_rom(pdev, &size);

nit: reverse xmas tree.

> +
> +	if (p) {
> +		int index = 0;
> +		int found;
> +
> +		if (is_quattro_p(pdev))
> +			index = PCI_SLOT(pdev->devfn);
> +
> +		found = readb(p) == 0x55 &&
> +			readb(p + 1) == 0xaa &&
> +			find_eth_addr_in_vpd(p, (64 * 1024), index, dev_addr);
> +		pci_unmap_rom(pdev, p);
> +		if (found)
> +			return;
> +	}
> +
> +	/* Sun MAC prefix then 3 random bytes. */
> +	dev_addr[0] = 0x08;
> +	dev_addr[1] = 0x00;
> +	dev_addr[2] = 0x20;
> +	get_random_bytes(&dev_addr[3], 3);
> +}
> +#endif /* !(CONFIG_SPARC) */

Should this be CONFIG_PCI ?

...

> @@ -2346,34 +2472,11 @@ static int happy_meal_sbus_probe_one(struct platform_device *op, int is_qfe)
>  		return -ENOMEM;
>  	SET_NETDEV_DEV(dev, &op->dev);
>  
> -	/* If user did not specify a MAC address specifically, use
> -	 * the Quattro local-mac-address property...
> -	 */
> -	for (i = 0; i < 6; i++) {
> -		if (macaddr[i] != 0)
> -			break;
> -	}
> -	if (i < 6) { /* a mac address was given */
> -		for (i = 0; i < 6; i++)
> -			addr[i] = macaddr[i];
> -		eth_hw_addr_set(dev, addr);
> -		macaddr[5]++;
> -	} else {
> -		const unsigned char *addr;
> -		int len;
> -
> -		addr = of_get_property(dp, "local-mac-address", &len);
> -
> -		if (qfe_slot != -1 && addr && len == ETH_ALEN)
> -			eth_hw_addr_set(dev, addr);
> -		else
> -			eth_hw_addr_set(dev, idprom->id_ethaddr);
> -	}
> -
>  	hp = netdev_priv(dev);
> -
> +	hp->dev = dev;

I'm not clear how this change relates to the rest of the patch.

>  	hp->happy_dev = op;
>  	hp->dma_dev = &op->dev;
> +	happy_meal_addr_init(hp, dp, qfe_slot);
>  
>  	spin_lock_init(&hp->happy_lock);
>  
> @@ -2451,7 +2554,6 @@ static int happy_meal_sbus_probe_one(struct platform_device *op, int is_qfe)
>  
>  	timer_setup(&hp->happy_timer, happy_meal_timer, 0);
>  
> -	hp->dev = dev;
>  	dev->netdev_ops = &hme_netdev_ops;
>  	dev->watchdog_timeo = 5*HZ;
>  	dev->ethtool_ops = &hme_ethtool_ops;

...

>  static int happy_meal_pci_probe(struct pci_dev *pdev,
>  				const struct pci_device_id *ent)
>  {
>  	struct quattro *qp = NULL;
> -#ifdef CONFIG_SPARC
> -	struct device_node *dp;

Was dp not being initialised previously a bug?

> -#endif
> +	struct device_node *dp = NULL;

nit: I think it would be good to move towards, rather than away from,
reverse xmas tree here.

>  	struct happy_meal *hp;
>  	struct net_device *dev;
>  	void __iomem *hpreg_base;
>  	struct resource *hpreg_res;
> -	int i, qfe_slot = -1;
> +	int qfe_slot = -1;
>  	char prom_name[64];
> -	u8 addr[ETH_ALEN];
>  	int err;
>  
>  	/* Now make sure pci_dev cookie is there. */

...

> @@ -2680,35 +2695,7 @@ static int happy_meal_pci_probe(struct pci_dev *pdev,
>  		goto err_out_clear_quattro;
>  	}
>  
> -	for (i = 0; i < 6; i++) {
> -		if (macaddr[i] != 0)
> -			break;
> -	}
> -	if (i < 6) { /* a mac address was given */
> -		for (i = 0; i < 6; i++)
> -			addr[i] = macaddr[i];
> -		eth_hw_addr_set(dev, addr);
> -		macaddr[5]++;
> -	} else {
> -#ifdef CONFIG_SPARC
> -		const unsigned char *addr;
> -		int len;
> -
> -		if (qfe_slot != -1 &&
> -		    (addr = of_get_property(dp, "local-mac-address", &len))
> -			!= NULL &&
> -		    len == 6) {
> -			eth_hw_addr_set(dev, addr);
> -		} else {
> -			eth_hw_addr_set(dev, idprom->id_ethaddr);
> -		}
> -#else
> -		u8 addr[ETH_ALEN];
> -
> -		get_hme_mac_nonsparc(pdev, addr);
> -		eth_hw_addr_set(dev, addr);
> -#endif
> -	}
> +	happy_meal_addr_init(hp, dp, qfe_slot);
>  
>  	/* Layout registers. */
>  	hp->gregs      = (hpreg_base + 0x0000UL);
> @@ -2757,7 +2744,6 @@ static int happy_meal_pci_probe(struct pci_dev *pdev,
>  	timer_setup(&hp->happy_timer, happy_meal_timer, 0);
>  
>  	hp->irq = pdev->irq;
> -	hp->dev = dev;
>  	dev->netdev_ops = &hme_netdev_ops;
>  	dev->watchdog_timeo = 5*HZ;
>  	dev->ethtool_ops = &hme_ethtool_ops;
> -- 
> 2.37.1
>