bmips: backport b53 legacy tags support
These patches have been accepted upstream for linux 5.13. Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
This commit is contained in:
		| @@ -0,0 +1,104 @@ | ||||
| From a3b0b6479700a5b0af2c631cb2ec0fb7a0d978f2 Mon Sep 17 00:00:00 2001 | ||||
| From: Vladimir Oltean <vladimir.oltean@nxp.com> | ||||
| Date: Sun, 1 Nov 2020 21:16:09 +0200 | ||||
| Subject: [PATCH] net: dsa: implement a central TX reallocation procedure | ||||
|  | ||||
| At the moment, taggers are left with the task of ensuring that the skb | ||||
| headers are writable (which they aren't, if the frames were cloned for | ||||
| TX timestamping, for flooding by the bridge, etc), and that there is | ||||
| enough space in the skb data area for the DSA tag to be pushed. | ||||
|  | ||||
| Moreover, the life of tail taggers is even harder, because they need to | ||||
| ensure that short frames have enough padding, a problem that normal | ||||
| taggers don't have. | ||||
|  | ||||
| The principle of the DSA framework is that everything except for the | ||||
| most intimate hardware specifics (like in this case, the actual packing | ||||
| of the DSA tag bits) should be done inside the core, to avoid having | ||||
| code paths that are very rarely tested. | ||||
|  | ||||
| So provide a TX reallocation procedure that should cover the known needs | ||||
| of DSA today. | ||||
|  | ||||
| Note that this patch also gives the network stack a good hint about the | ||||
| headroom/tailroom it's going to need. Up till now it wasn't doing that. | ||||
| So the reallocation procedure should really be there only for the | ||||
| exceptional cases, and for cloned packets which need to be unshared. | ||||
|  | ||||
| Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> | ||||
| Tested-by: Christian Eggers <ceggers@arri.de> # For tail taggers only | ||||
| Tested-by: Kurt Kanzenbach <kurt@linutronix.de> | ||||
| Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> | ||||
| Signed-off-by: Jakub Kicinski <kuba@kernel.org> | ||||
| --- | ||||
|  net/dsa/slave.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ | ||||
|  1 file changed, 45 insertions(+) | ||||
|  | ||||
| --- a/net/dsa/slave.c | ||||
| +++ b/net/dsa/slave.c | ||||
| @@ -548,6 +548,30 @@ netdev_tx_t dsa_enqueue_skb(struct sk_bu | ||||
|  } | ||||
|  EXPORT_SYMBOL_GPL(dsa_enqueue_skb); | ||||
|   | ||||
| +static int dsa_realloc_skb(struct sk_buff *skb, struct net_device *dev) | ||||
| +{ | ||||
| +	int needed_headroom = dev->needed_headroom; | ||||
| +	int needed_tailroom = dev->needed_tailroom; | ||||
| + | ||||
| +	/* For tail taggers, we need to pad short frames ourselves, to ensure | ||||
| +	 * that the tail tag does not fail at its role of being at the end of | ||||
| +	 * the packet, once the master interface pads the frame. Account for | ||||
| +	 * that pad length here, and pad later. | ||||
| +	 */ | ||||
| +	if (unlikely(needed_tailroom && skb->len < ETH_ZLEN)) | ||||
| +		needed_tailroom += ETH_ZLEN - skb->len; | ||||
| +	/* skb_headroom() returns unsigned int... */ | ||||
| +	needed_headroom = max_t(int, needed_headroom - skb_headroom(skb), 0); | ||||
| +	needed_tailroom = max_t(int, needed_tailroom - skb_tailroom(skb), 0); | ||||
| + | ||||
| +	if (likely(!needed_headroom && !needed_tailroom && !skb_cloned(skb))) | ||||
| +		/* No reallocation needed, yay! */ | ||||
| +		return 0; | ||||
| + | ||||
| +	return pskb_expand_head(skb, needed_headroom, needed_tailroom, | ||||
| +				GFP_ATOMIC); | ||||
| +} | ||||
| + | ||||
|  static netdev_tx_t dsa_slave_xmit(struct sk_buff *skb, struct net_device *dev) | ||||
|  { | ||||
|  	struct dsa_slave_priv *p = netdev_priv(dev); | ||||
| @@ -567,6 +591,17 @@ static netdev_tx_t dsa_slave_xmit(struct | ||||
|  	 */ | ||||
|  	dsa_skb_tx_timestamp(p, skb); | ||||
|   | ||||
| +	if (dsa_realloc_skb(skb, dev)) { | ||||
| +		dev_kfree_skb_any(skb); | ||||
| +		return NETDEV_TX_OK; | ||||
| +	} | ||||
| + | ||||
| +	/* needed_tailroom should still be 'warm' in the cache line from | ||||
| +	 * dsa_realloc_skb(), which has also ensured that padding is safe. | ||||
| +	 */ | ||||
| +	if (dev->needed_tailroom) | ||||
| +		eth_skb_pad(skb); | ||||
| + | ||||
|  	/* Transmit function may have to reallocate the original SKB, | ||||
|  	 * in which case it must have freed it. Only free it here on error. | ||||
|  	 */ | ||||
| @@ -1825,6 +1860,16 @@ int dsa_slave_create(struct dsa_port *po | ||||
|  	slave_dev->netdev_ops = &dsa_slave_netdev_ops; | ||||
|  	if (ds->ops->port_max_mtu) | ||||
|  		slave_dev->max_mtu = ds->ops->port_max_mtu(ds, port->index); | ||||
| +	if (cpu_dp->tag_ops->tail_tag) | ||||
| +		slave_dev->needed_tailroom = cpu_dp->tag_ops->overhead; | ||||
| +	else | ||||
| +		slave_dev->needed_headroom = cpu_dp->tag_ops->overhead; | ||||
| +	/* Try to save one extra realloc later in the TX path (in the master) | ||||
| +	 * by also inheriting the master's needed headroom and tailroom. | ||||
| +	 * The 8021q driver also does this. | ||||
| +	 */ | ||||
| +	slave_dev->needed_headroom += master->needed_headroom; | ||||
| +	slave_dev->needed_tailroom += master->needed_tailroom; | ||||
|  	SET_NETDEV_DEVTYPE(slave_dev, &dsa_type); | ||||
|   | ||||
|  	netdev_for_each_tx_queue(slave_dev, dsa_slave_set_lockdep_class_one, | ||||
| @@ -1,59 +1,22 @@ | ||||
| From 3bc3d79efdff6e29b80bf35f7a56baaa36e4d8fe Mon Sep 17 00:00:00 2001 | ||||
| From 964dbf186eaa84d409c359ddf09c827a3fbe8228 Mon Sep 17 00:00:00 2001 | ||||
| From: =?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= <noltari@gmail.com> | ||||
| Date: Fri, 12 Mar 2021 12:35:39 +0100 | ||||
| Subject: [PATCH] net: dsa: b53: support tags for legacy switches | ||||
| Date: Wed, 17 Mar 2021 11:29:26 +0100 | ||||
| Subject: [PATCH 1/2] net: dsa: tag_brcm: add support for legacy tags | ||||
| MIME-Version: 1.0 | ||||
| Content-Type: text/plain; charset=UTF-8 | ||||
| Content-Transfer-Encoding: 8bit | ||||
| 
 | ||||
| Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com> | ||||
| ---
 | ||||
|  drivers/net/dsa/b53/Kconfig      |  1 + | ||||
|  drivers/net/dsa/b53/b53_common.c |  6 +++ | ||||
|  include/net/dsa.h                |  2 + | ||||
|  net/dsa/Kconfig                  |  7 +++ | ||||
|  net/dsa/tag_brcm.c               | 93 ++++++++++++++++++++++++++++++++ | ||||
|  5 files changed, 109 insertions(+) | ||||
| Add support for legacy Broadcom tags, which are similar to DSA_TAG_PROTO_BRCM. | ||||
| These tags are used on BCM5325, BCM5365 and BCM63xx switches. | ||||
| 
 | ||||
| Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com> | ||||
| Signed-off-by: David S. Miller <davem@davemloft.net> | ||||
| ---
 | ||||
|  include/net/dsa.h  |   2 + | ||||
|  net/dsa/Kconfig    |   7 +++ | ||||
|  net/dsa/tag_brcm.c | 107 +++++++++++++++++++++++++++++++++++++++++++-- | ||||
|  3 files changed, 113 insertions(+), 3 deletions(-) | ||||
| 
 | ||||
| --- a/drivers/net/dsa/b53/Kconfig
 | ||||
| +++ b/drivers/net/dsa/b53/Kconfig
 | ||||
| @@ -3,6 +3,7 @@ menuconfig B53
 | ||||
|  	tristate "Broadcom BCM53xx managed switch support" | ||||
|  	depends on NET_DSA | ||||
|  	select NET_DSA_TAG_BRCM | ||||
| +	select NET_DSA_TAG_BRCM_LEGACY
 | ||||
|  	select NET_DSA_TAG_BRCM_PREPEND | ||||
|  	help | ||||
|  	  This driver adds support for Broadcom managed switch chips. It supports | ||||
| --- a/drivers/net/dsa/b53/b53_common.c
 | ||||
| +++ b/drivers/net/dsa/b53/b53_common.c
 | ||||
| @@ -1992,6 +1992,7 @@ static bool b53_can_enable_brcm_tags(str
 | ||||
|   | ||||
|  	switch (tag_protocol) { | ||||
|  	case DSA_TAG_PROTO_BRCM: | ||||
| +	case DSA_TAG_PROTO_BRCM_LEGACY:
 | ||||
|  	case DSA_TAG_PROTO_BRCM_PREPEND: | ||||
|  		dev_warn(ds->dev, | ||||
|  			 "Port %d is stacked to Broadcom tag switch\n", port); | ||||
| @@ -2013,12 +2014,16 @@ enum dsa_tag_protocol b53_get_tag_protoc
 | ||||
|  	/* Older models (5325, 5365) support a different tag format that we do | ||||
|  	 * not support in net/dsa/tag_brcm.c yet. | ||||
|  	 */ | ||||
| -	if (is5325(dev) || is5365(dev) ||
 | ||||
| -	    !b53_can_enable_brcm_tags(ds, port, mprot)) {
 | ||||
| +	if (!b53_can_enable_brcm_tags(ds, port, mprot)) {
 | ||||
|  		dev->tag_protocol = DSA_TAG_PROTO_NONE; | ||||
|  		goto out; | ||||
|  	} | ||||
|   | ||||
| +	if (is5325(dev) || is5365(dev) || is63xx(dev)) {
 | ||||
| +		dev->tag_protocol = DSA_TAG_PROTO_BRCM_LEGACY;
 | ||||
| +		goto out;
 | ||||
| +	}
 | ||||
| +
 | ||||
|  	/* Broadcom BCM58xx chips have a flow accelerator on Port 8 | ||||
|  	 * which requires us to use the prepended Broadcom tag type | ||||
|  	 */ | ||||
| --- a/include/net/dsa.h
 | ||||
| +++ b/include/net/dsa.h
 | ||||
| @@ -45,10 +45,12 @@ struct phylink_link_state;
 | ||||
| @@ -87,31 +50,37 @@ Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com> | ||||
|  	tristate "Tag driver for Broadcom switches using prepended headers" | ||||
| --- a/net/dsa/tag_brcm.c
 | ||||
| +++ b/net/dsa/tag_brcm.c
 | ||||
| @@ -8,9 +8,23 @@
 | ||||
|  #include <linux/etherdevice.h> | ||||
|  #include <linux/list.h> | ||||
|  #include <linux/slab.h> | ||||
| +#include <linux/types.h>
 | ||||
| @@ -11,9 +11,26 @@
 | ||||
|   | ||||
|  #include "dsa_priv.h" | ||||
|   | ||||
| +struct bcm_legacy_tag {
 | ||||
| +	uint16_t type;
 | ||||
| +#define BRCM_LEG_TYPE	0x8874
 | ||||
| -/* This tag length is 4 bytes, older ones were 6 bytes, we do not
 | ||||
| - * handle them
 | ||||
| - */
 | ||||
| +/* Legacy Broadcom tag (6 bytes) */
 | ||||
| +#define BRCM_LEG_TAG_LEN	6
 | ||||
| +
 | ||||
| +	uint32_t tag;
 | ||||
| +#define BRCM_LEG_TAG_PORT_ID	(0xf)
 | ||||
| +#define BRCM_LEG_TAG_MULTICAST	(1 << 29)
 | ||||
| +#define BRCM_LEG_TAG_EGRESS	(2 << 29)
 | ||||
| +#define BRCM_LEG_TAG_INGRESS	(3 << 29)
 | ||||
| +} __attribute__((packed));
 | ||||
| +/* Type fields */
 | ||||
| +/* 1st byte in the tag */
 | ||||
| +#define BRCM_LEG_TYPE_HI	0x88
 | ||||
| +/* 2nd byte in the tag */
 | ||||
| +#define BRCM_LEG_TYPE_LO	0x74
 | ||||
| +
 | ||||
| +#define BRCM_LEG_TAG_LEN	sizeof(struct bcm_legacy_tag)
 | ||||
| +/* Tag fields */
 | ||||
| +/* 3rd byte in the tag */
 | ||||
| +#define BRCM_LEG_UNICAST	(0 << 5)
 | ||||
| +#define BRCM_LEG_MULTICAST	(1 << 5)
 | ||||
| +#define BRCM_LEG_EGRESS		(2 << 5)
 | ||||
| +#define BRCM_LEG_INGRESS	(3 << 5)
 | ||||
| +
 | ||||
|  /* This tag length is 4 bytes, older ones were 6 bytes, we do not | ||||
|   * handle them | ||||
|   */ | ||||
| @@ -197,6 +211,85 @@ DSA_TAG_DRIVER(brcm_netdev_ops);
 | ||||
| +/* 6th byte in the tag */
 | ||||
| +#define BRCM_LEG_PORT_ID	(0xf)
 | ||||
| +
 | ||||
| +/* Newer Broadcom tag (4 bytes) */
 | ||||
|  #define BRCM_TAG_LEN	4 | ||||
|   | ||||
|  /* Tag is constructed and desconstructed using byte by byte access | ||||
| @@ -197,6 +214,87 @@ DSA_TAG_DRIVER(brcm_netdev_ops);
 | ||||
|  MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM); | ||||
|  #endif | ||||
|   | ||||
| @@ -120,10 +89,7 @@ Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com> | ||||
| +					 struct net_device *dev)
 | ||||
| +{
 | ||||
| +	struct dsa_port *dp = dsa_slave_to_port(dev);
 | ||||
| +	struct bcm_legacy_tag *brcm_tag;
 | ||||
| +
 | ||||
| +	if (skb_cow_head(skb, BRCM_LEG_TAG_LEN) < 0)
 | ||||
| +		return NULL;
 | ||||
| +	u8 *brcm_tag;
 | ||||
| +
 | ||||
| +	/* The Ethernet switch we are interfaced with needs packets to be at
 | ||||
| +	 * least 64 bytes (including FCS) otherwise they will be discarded when
 | ||||
| @@ -141,29 +107,34 @@ Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com> | ||||
| +
 | ||||
| +	memmove(skb->data, skb->data + BRCM_LEG_TAG_LEN, 2 * ETH_ALEN);
 | ||||
| +
 | ||||
| +	brcm_tag = (struct bcm_legacy_tag *) (skb->data + 2 * ETH_ALEN);
 | ||||
| +	brcm_tag = skb->data + 2 * ETH_ALEN;
 | ||||
| +
 | ||||
| +	brcm_tag->type = BRCM_LEG_TYPE;
 | ||||
| +	brcm_tag->tag = BRCM_LEG_TAG_EGRESS;
 | ||||
| +	brcm_tag->tag |= dp->index & BRCM_LEG_TAG_PORT_ID;
 | ||||
| +	/* Broadcom tag type */
 | ||||
| +	brcm_tag[0] = BRCM_LEG_TYPE_HI;
 | ||||
| +	brcm_tag[1] = BRCM_LEG_TYPE_LO;
 | ||||
| +
 | ||||
| +	/* Broadcom tag value */
 | ||||
| +	brcm_tag[2] = BRCM_LEG_EGRESS;
 | ||||
| +	brcm_tag[3] = 0;
 | ||||
| +	brcm_tag[4] = 0;
 | ||||
| +	brcm_tag[5] = dp->index & BRCM_LEG_PORT_ID;
 | ||||
| +
 | ||||
| +	return skb;
 | ||||
| +}
 | ||||
| +
 | ||||
| +
 | ||||
| +static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb,
 | ||||
| +					struct net_device *dev,
 | ||||
| +					struct packet_type *pt)
 | ||||
| +{
 | ||||
| +	int source_port;
 | ||||
| +	struct bcm_legacy_tag *brcm_tag;
 | ||||
| +	u8 *brcm_tag;
 | ||||
| +
 | ||||
| +	if (unlikely(!pskb_may_pull(skb, BRCM_LEG_TAG_LEN)))
 | ||||
| +	if (unlikely(!pskb_may_pull(skb, BRCM_LEG_PORT_ID)))
 | ||||
| +		return NULL;
 | ||||
| +
 | ||||
| +	brcm_tag = (struct bcm_legacy_tag *) (skb->data - 2);
 | ||||
| +	brcm_tag = skb->data - 2;
 | ||||
| +
 | ||||
| +	source_port = brcm_tag->tag & BRCM_LEG_TAG_PORT_ID;
 | ||||
| +	source_port = brcm_tag[5] & BRCM_LEG_PORT_ID;
 | ||||
| +
 | ||||
| +	skb->dev = dsa_master_find_slave(dev, 0, source_port);
 | ||||
| +	if (!skb->dev)
 | ||||
| @@ -183,10 +154,10 @@ Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com> | ||||
| +}
 | ||||
| +
 | ||||
| +static const struct dsa_device_ops brcm_legacy_netdev_ops = {
 | ||||
| +	.name	= "brcm-legacy",
 | ||||
| +	.proto	= DSA_TAG_PROTO_BRCM_LEGACY,
 | ||||
| +	.xmit	= brcm_leg_tag_xmit,
 | ||||
| +	.rcv	= brcm_leg_tag_rcv,
 | ||||
| +	.name = "brcm-legacy",
 | ||||
| +	.proto = DSA_TAG_PROTO_BRCM_LEGACY,
 | ||||
| +	.xmit = brcm_leg_tag_xmit,
 | ||||
| +	.rcv = brcm_leg_tag_rcv,
 | ||||
| +	.overhead = BRCM_LEG_TAG_LEN,
 | ||||
| +};
 | ||||
| +
 | ||||
| @@ -197,7 +168,7 @@ Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com> | ||||
|  #if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_PREPEND) | ||||
|  static struct sk_buff *brcm_tag_xmit_prepend(struct sk_buff *skb, | ||||
|  					     struct net_device *dev) | ||||
| @@ -229,6 +322,9 @@ static struct dsa_tag_driver *dsa_tag_dr
 | ||||
| @@ -229,6 +327,9 @@ static struct dsa_tag_driver *dsa_tag_dr
 | ||||
|  #if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM) | ||||
|  	&DSA_TAG_DRIVER_NAME(brcm_netdev_ops), | ||||
|  #endif | ||||
| @@ -0,0 +1,53 @@ | ||||
| From 46c5176c586c81306bf9e7024c13b95da775490f Mon Sep 17 00:00:00 2001 | ||||
| From: =?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= <noltari@gmail.com> | ||||
| Date: Wed, 17 Mar 2021 11:29:27 +0100 | ||||
| Subject: [PATCH 2/2] net: dsa: b53: support legacy tags | ||||
| MIME-Version: 1.0 | ||||
| Content-Type: text/plain; charset=UTF-8 | ||||
| Content-Transfer-Encoding: 8bit | ||||
|  | ||||
| These tags are used on BCM5325, BCM5365 and BCM63xx switches. | ||||
|  | ||||
| Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com> | ||||
| Acked-by: Florian Fainelli <f.fainelli@gmail.com> | ||||
| Signed-off-by: David S. Miller <davem@davemloft.net> | ||||
| --- | ||||
|  drivers/net/dsa/b53/Kconfig      |  1 + | ||||
|  drivers/net/dsa/b53/b53_common.c | 12 +++++++----- | ||||
|  2 files changed, 8 insertions(+), 5 deletions(-) | ||||
|  | ||||
| --- a/drivers/net/dsa/b53/Kconfig | ||||
| +++ b/drivers/net/dsa/b53/Kconfig | ||||
| @@ -3,6 +3,7 @@ menuconfig B53 | ||||
|  	tristate "Broadcom BCM53xx managed switch support" | ||||
|  	depends on NET_DSA | ||||
|  	select NET_DSA_TAG_BRCM | ||||
| +	select NET_DSA_TAG_BRCM_LEGACY | ||||
|  	select NET_DSA_TAG_BRCM_PREPEND | ||||
|  	help | ||||
|  	  This driver adds support for Broadcom managed switch chips. It supports | ||||
| --- a/drivers/net/dsa/b53/b53_common.c | ||||
| +++ b/drivers/net/dsa/b53/b53_common.c | ||||
| @@ -2010,15 +2010,17 @@ enum dsa_tag_protocol b53_get_tag_protoc | ||||
|  { | ||||
|  	struct b53_device *dev = ds->priv; | ||||
|   | ||||
| -	/* Older models (5325, 5365) support a different tag format that we do | ||||
| -	 * not support in net/dsa/tag_brcm.c yet. | ||||
| -	 */ | ||||
| -	if (is5325(dev) || is5365(dev) || | ||||
| -	    !b53_can_enable_brcm_tags(ds, port, mprot)) { | ||||
| +	if (!b53_can_enable_brcm_tags(ds, port, mprot)) { | ||||
|  		dev->tag_protocol = DSA_TAG_PROTO_NONE; | ||||
|  		goto out; | ||||
|  	} | ||||
|   | ||||
| +	/* Older models require a different 6 byte tag */ | ||||
| +	if (is5325(dev) || is5365(dev) || is63xx(dev)) { | ||||
| +		dev->tag_protocol = DSA_TAG_PROTO_BRCM_LEGACY; | ||||
| +		goto out; | ||||
| +	} | ||||
| + | ||||
|  	/* Broadcom BCM58xx chips have a flow accelerator on Port 8 | ||||
|  	 * which requires us to use the prepended Broadcom tag type | ||||
|  	 */ | ||||
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