[PATCH v1 RFC 7/7] Modify tag_ksz.c so that tail tag code can be used by other KSZ switch drivers

Tristram.Ha
2017-10-06T20:33:19Z

From: Tristram Ha <Tristram.Ha@microchip.com>

Modify tag_ksz.c so that tail tag code can be used by other KSZ switch
drivers.

Signed-off-by: Tristram Ha <Tristram.Ha@microchip.com>
---
drivers/net/dsa/microchip/Kconfig | 2 +-
drivers/net/dsa/microchip/ksz9477.c | 2 +-
include/net/dsa.h | 2 +-
net/dsa/Kconfig | 4 ++
net/dsa/dsa.c | 4 +-
net/dsa/dsa_priv.h | 2 +-
net/dsa/tag_ksz.c | 107 ++++++++++++++++++++++++++----------
7 files changed, 88 insertions(+), 35 deletions(-)

diff --git a/drivers/net/dsa/microchip/Kconfig b/drivers/net/dsa/microchip/Kconfig
index 5a8660d..ab8f9f6 100644
--- a/drivers/net/dsa/microchip/Kconfig
+++ b/drivers/net/dsa/microchip/Kconfig
@@ -1,7 +1,7 @@
menuconfig MICROCHIP_KSZ9477
tristate "Microchip KSZ9477 series switch support"
depends on NET_DSA
- select NET_DSA_TAG_KSZ
+ select NET_DSA_TAG_KSZ9477
help
This driver adds support for Microchip KSZ9477 switch chips.

diff --git a/drivers/net/dsa/microchip/ksz9477.c b/drivers/net/dsa/microchip/ksz9477.c
index 9579d03..e6d2956 100644
--- a/drivers/net/dsa/microchip/ksz9477.c
+++ b/drivers/net/dsa/microchip/ksz9477.c
@@ -342,7 +342,7 @@ static void ksz9477_port_init_cnt(struct ksz_device *dev, int port)

static enum dsa_tag_protocol ksz9477_get_tag_protocol(struct dsa_switch *ds)
{
- return DSA_TAG_PROTO_KSZ;
+ return DSA_TAG_PROTO_KSZ9477;
}

static int ksz9477_phy_read16(struct dsa_switch *ds, int addr, int reg)
diff --git a/include/net/dsa.h b/include/net/dsa.h
index 10dcecc..28cdc5e 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -31,7 +31,7 @@ enum dsa_tag_protocol {
DSA_TAG_PROTO_BRCM,
DSA_TAG_PROTO_DSA,
DSA_TAG_PROTO_EDSA,
- DSA_TAG_PROTO_KSZ,
+ DSA_TAG_PROTO_KSZ9477,
DSA_TAG_PROTO_LAN9303,
DSA_TAG_PROTO_MTK,
DSA_TAG_PROTO_QCA,
diff --git a/net/dsa/Kconfig b/net/dsa/Kconfig
index cc5f8f9..d2bbd21 100644
--- a/net/dsa/Kconfig
+++ b/net/dsa/Kconfig
@@ -28,6 +28,10 @@ config NET_DSA_TAG_EDSA
config NET_DSA_TAG_KSZ
bool

+config NET_DSA_TAG_KSZ9477
+ bool
+ select NET_DSA_TAG_KSZ
+
config NET_DSA_TAG_LAN9303
bool

diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 51ca2a5..cc03a09 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -49,8 +49,8 @@ static struct sk_buff *dsa_slave_notag_xmit(struct sk_buff *skb,
#ifdef CONFIG_NET_DSA_TAG_EDSA
[DSA_TAG_PROTO_EDSA] = &edsa_netdev_ops,
#endif
-#ifdef CONFIG_NET_DSA_TAG_KSZ
- [DSA_TAG_PROTO_KSZ] = &ksz_netdev_ops,
+#ifdef CONFIG_NET_DSA_TAG_KSZ9477
+ [DSA_TAG_PROTO_KSZ9477] = &ksz9477_netdev_ops,
#endif
#ifdef CONFIG_NET_DSA_TAG_LAN9303
[DSA_TAG_PROTO_LAN9303] = &lan9303_netdev_ops,
diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index 2850077c..e0dc2d4 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -183,7 +183,7 @@ int dsa_port_vlan_del(struct dsa_port *dp,
extern const struct dsa_device_ops edsa_netdev_ops;

/* tag_ksz.c */
-extern const struct dsa_device_ops ksz_netdev_ops;
+extern const struct dsa_device_ops ksz9477_netdev_ops;

/* tag_lan9303.c */
extern const struct dsa_device_ops lan9303_netdev_ops;
diff --git a/net/dsa/tag_ksz.c b/net/dsa/tag_ksz.c
index b241c99..1bb5b7d 100644
--- a/net/dsa/tag_ksz.c
+++ b/net/dsa/tag_ksz.c
@@ -14,34 +14,28 @@
#include <net/dsa.h>
#include "dsa_priv.h"

-/* For Ingress (Host -> KSZ), 2 bytes are added before FCS.
- * ---------------------------------------------------------------------------
- * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|tag1(1byte)|FCS(4bytes)
- * ---------------------------------------------------------------------------
- * tag0 : Prioritization (not used now)
- * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
- *
- * For Egress (KSZ -> Host), 1 byte is added before FCS.
- * ---------------------------------------------------------------------------
- * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
- * ---------------------------------------------------------------------------
- * tag0 : zero-based value represents port
- * (eg, 0x00=port1, 0x02=port3, 0x06=port7)
- */
+/* Typically only one byte is used for tail tag. */
+#define KSZ_EGRESS_TAG_LEN 1
+#define KSZ_INGRESS_TAG_LEN 1

-#define KSZ_INGRESS_TAG_LEN 2
-#define KSZ_EGRESS_TAG_LEN 1
+/* Frames with following addresse may need to be sent even when the port is
+ * closed.
+ */
+static const u8 special_mult_addr[] = {
+ 0x01, 0x80, 0xC2, 0x00, 0x00, 0x00
+};

-static struct sk_buff *ksz_xmit(struct sk_buff *skb, struct net_device *dev)
+static struct sk_buff *ksz_xmit(struct sk_buff *skb, struct net_device *dev,
+ int len,
+ void (*set_tag)(void *ptr, u8 *addr, int p))
{
struct dsa_slave_priv *p = netdev_priv(dev);
struct sk_buff *nskb;
int padlen;
- u8 *tag;

padlen = (skb->len >= ETH_ZLEN) ? 0 : ETH_ZLEN - skb->len;

- if (skb_tailroom(skb) >= padlen + KSZ_INGRESS_TAG_LEN) {
+ if (skb_tailroom(skb) >= padlen + len) {
/* Let dsa_slave_xmit() free skb */
if (__skb_put_padto(skb, skb->len + padlen, false))
return NULL;
@@ -49,7 +43,7 @@ static struct sk_buff *ksz_xmit(struct sk_buff *skb, struct net_device *dev)
nskb = skb;
} else {
nskb = alloc_skb(NET_IP_ALIGN + skb->len +
- padlen + KSZ_INGRESS_TAG_LEN, GFP_ATOMIC);
+ padlen + len, GFP_ATOMIC);
if (!nskb)
return NULL;
skb_reserve(nskb, NET_IP_ALIGN);
@@ -70,33 +64,88 @@ static struct sk_buff *ksz_xmit(struct sk_buff *skb, struct net_device *dev)
consume_skb(skb);
}

- tag = skb_put(nskb, KSZ_INGRESS_TAG_LEN);
- tag[0] = 0;
- tag[1] = 1 << p->dp->index; /* destination port */
+ set_tag(skb_put(nskb, len), skb_mac_header(nskb), p->dp->index);

return nskb;
}

static struct sk_buff *ksz_rcv(struct sk_buff *skb, struct net_device *dev,
- struct packet_type *pt)
+ struct packet_type *pt,
+ int (*get_tag)(u8 *tag, int *port))
{
u8 *tag;
+ int len;
int source_port;

tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;

- source_port = tag[0] & 7;
+ len = get_tag(tag, &source_port);

skb->dev = dsa_master_get_slave(dev, 0, source_port);
if (!skb->dev)
return NULL;

- pskb_trim_rcsum(skb, skb->len - KSZ_EGRESS_TAG_LEN);
+ pskb_trim_rcsum(skb, skb->len - len);

return skb;
}

-const struct dsa_device_ops ksz_netdev_ops = {
- .xmit = ksz_xmit,
- .rcv = ksz_rcv,
+/* For Ingress (Host -> KSZ9477), 2 bytes are added before FCS.
+ * ---------------------------------------------------------------------------
+ * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|tag1(1byte)|FCS(4bytes)
+ * ---------------------------------------------------------------------------
+ * tag0 : Prioritization (not used now)
+ * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
+ *
+ * For Egress (KSZ9477 -> Host), 1 byte is added before FCS.
+ * ---------------------------------------------------------------------------
+ * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
+ * ---------------------------------------------------------------------------
+ * tag0 : zero-based value represents port
+ * (eg, 0x00=port1, 0x02=port3, 0x06=port7)
+ */
+
+#define KSZ9477_INGRESS_TAG_LEN 2
+#define KSZ9477_PTP_TAG_LEN 4
+#define KSZ9477_PTP_TAG_INDICATION 0x80
+
+#define KSZ9477_TAIL_TAG_OVERRIDE BIT(9)
+#define KSZ9477_TAIL_TAG_LOOKUP BIT(10)
+
+static int ksz9477_get_tag(u8 *tag, int *port)
+{
+ int len = KSZ_EGRESS_TAG_LEN;
+
+ /* Extra 4-bytes PTP timestamp */
+ if (tag[0] & KSZ9477_PTP_TAG_INDICATION)
+ len += KSZ9477_PTP_TAG_LEN;
+ *port = tag[0] & 7;
+ return len;
+}
+
+static void ksz9477_set_tag(void *ptr, u8 *addr, int p)
+{
+ u16 *tag = (u16 *)ptr;
+
+ *tag = 1 << p;
+ if (!memcmp(addr, special_mult_addr, ETH_ALEN))
+ *tag |= KSZ9477_TAIL_TAG_OVERRIDE;
+ *tag = cpu_to_be16(*tag);
+}
+
+static struct sk_buff *ksz9477_xmit(struct sk_buff *skb,
+ struct net_device *dev)
+{
+ return ksz_xmit(skb, dev, KSZ9477_INGRESS_TAG_LEN, ksz9477_set_tag);
+}
+
+static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt)
+{
+ return ksz_rcv(skb, dev, pt, ksz9477_get_tag);
+}
+
+const struct dsa_device_ops ksz9477_netdev_ops = {
+ .xmit = ksz9477_xmit,
+ .rcv = ksz9477_rcv,
};
--
1.9.1