* [RFC 1/3] caif: Add support for flow-control on device's tx-queue
2011-11-30 20:44 [RFC 0/3] caif: Add support for CAIF over CDC NCM USB interface Sjur Br��ndeland
@ 2011-11-30 20:44 ` Sjur Br��ndeland
2011-11-30 20:44 ` [RFC 2/3] if_ether.h: Add IEEE 802.1 Local Experimental Ethertype 1 Sjur Br��ndeland
2011-11-30 20:44 ` [RFC 3/3] caif: Add support for CAIF over CDC NCM USB interface Sjur Br��ndeland
2 siblings, 0 replies; 9+ messages in thread
From: Sjur Br��ndeland @ 2011-11-30 20:44 UTC (permalink / raw)
To: netdev; +Cc: David Miller, Alexey Orishko, Sjur Brændeland
From: Sjur Brændeland <sjur.brandeland@stericsson.com>
Flow control is implemented by inspecting the qdisc queue length
in order to detect potential overflow on the TX queue. When a threshold
is reached flow-off is sent upwards in the CAIF stack. At the same time
the skb->destructor is hi-jacked in order to detect when the last packet
put on queue is consumed. When this "hi-jacked" packet is consumed, flow-on
is sent upwards in the CAIF stack.
Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
---
net/caif/caif_dev.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 48 insertions(+), 0 deletions(-)
diff --git a/net/caif/caif_dev.c b/net/caif/caif_dev.c
index f7e8c70..415353e 100644
--- a/net/caif/caif_dev.c
+++ b/net/caif/caif_dev.c
@@ -34,6 +34,7 @@ struct caif_device_entry {
struct list_head list;
struct net_device *netdev;
int __percpu *pcpu_refcnt;
+ bool xoff;
};
struct caif_device_entry_list {
@@ -48,6 +49,7 @@ struct caif_net {
};
static int caif_net_id;
+static int q_high = 50; /* Percent */
struct cfcnfg *get_cfcnfg(struct net *net)
{
@@ -126,9 +128,28 @@ static struct caif_device_entry *caif_get(struct net_device *dev)
return NULL;
}
+void caif_flow_cb(struct sk_buff *skb)
+{
+ struct caif_device_entry *caifd;
+ WARN_ON(skb->dev == NULL);
+
+ rcu_read_lock();
+ caifd = caif_get(skb->dev);
+ caifd->xoff = 0;
+ caifd_hold(caifd);
+ rcu_read_unlock();
+
+ caifd->layer.up->
+ ctrlcmd(caifd->layer.up,
+ _CAIF_CTRLCMD_PHYIF_FLOW_ON_IND,
+ caifd->layer.id);
+ caifd_put(caifd);
+}
+
static int transmit(struct cflayer *layer, struct cfpkt *pkt)
{
int err;
+ struct caif_dev_common *caifdev;
struct caif_device_entry *caifd =
container_of(layer, struct caif_device_entry, layer);
struct sk_buff *skb;
@@ -137,6 +158,33 @@ static int transmit(struct cflayer *layer, struct cfpkt *pkt)
skb->dev = caifd->netdev;
skb_reset_network_header(skb);
skb->protocol = htons(ETH_P_CAIF);
+ caifdev = netdev_priv(caifd->netdev);
+
+ if (caifdev->flowctrl == NULL && caifd->netdev->tx_queue_len > 0 &&
+ !caifd->xoff) {
+ struct netdev_queue *txq;
+ int high;
+
+ txq = netdev_get_tx_queue(skb->dev, 0);
+ high = (caifd->netdev->tx_queue_len * q_high) / 100;
+
+ /* If we run with a TX queue, check if the queue is too long*/
+ if (netif_queue_stopped(caifd->netdev) ||
+ qdisc_qlen(txq->qdisc) > high) {
+
+ pr_debug("queue stop(%d) or full (%d>%d) - XOFF\n",
+ netif_queue_stopped(caifd->netdev),
+ qdisc_qlen(txq->qdisc), high);
+ caifd->xoff = 1;
+ /* Hijack this skb free callback function. */
+ skb_orphan(skb);
+ skb->destructor = caif_flow_cb;
+ caifd->layer.up->
+ ctrlcmd(caifd->layer.up,
+ _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND,
+ caifd->layer.id);
+ }
+ }
err = dev_queue_xmit(skb);
if (err > 0)
--
1.7.0.4
^ permalink raw reply related [flat|nested] 9+ messages in thread* [RFC 3/3] caif: Add support for CAIF over CDC NCM USB interface
2011-11-30 20:44 [RFC 0/3] caif: Add support for CAIF over CDC NCM USB interface Sjur Br��ndeland
2011-11-30 20:44 ` [RFC 1/3] caif: Add support for flow-control on device's tx-queue Sjur Br��ndeland
2011-11-30 20:44 ` [RFC 2/3] if_ether.h: Add IEEE 802.1 Local Experimental Ethertype 1 Sjur Br��ndeland
@ 2011-11-30 20:44 ` Sjur Br��ndeland
2 siblings, 0 replies; 9+ messages in thread
From: Sjur Br��ndeland @ 2011-11-30 20:44 UTC (permalink / raw)
To: netdev; +Cc: David Miller, Alexey Orishko, Sjur Brændeland
From: Sjur Brændeland <sjur.brandeland@stericsson.com>
NCM 1.0 does not support anything but Ethernet framing, hence
CAIF payload will be put into Ethernet frames.
Discovery is based on fixed USB vendor 0x04cc (ST-Ericsson),
product-id 0x230f (NCM). In this variant only CAIF payload is sent over
the NCM interface.
The CAIF stack (cfusbl.c) will when USB registers first check if
we got a CDC NCM USB interface with the right VID, PID.
It will then read the device's Ethernet address and create a 'template'
Ethernet TX header, using a broadcast address as the destination address,
and EthType 0x88b5 (802.1 Local Experimental - vendor specific).
A protocol handler for 0x88b5 is setup for reception of CAIF frames from
the CDC NCM USB interface.
Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
---
include/net/caif/cfusbl.h | 13 +++
net/caif/Kconfig | 11 +++
net/caif/Makefile | 4 +-
net/caif/caif_dev.c | 7 ++
net/caif/cfusbl.c | 199 +++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 233 insertions(+), 1 deletions(-)
create mode 100644 include/net/caif/cfusbl.h
create mode 100644 net/caif/cfusbl.c
diff --git a/include/net/caif/cfusbl.h b/include/net/caif/cfusbl.h
new file mode 100644
index 0000000..7ef2499
--- /dev/null
+++ b/include/net/caif/cfusbl.h
@@ -0,0 +1,13 @@
+/*
+ * Copyright (C) ST-Ericsson AB 2010
+ * Author: Sjur Brendeland/sjur.brandeland@stericsson.com
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#ifndef CFUSBL_H_
+#define CFUSBL_H_
+
+void cfusbl_init(void);
+void cfusbl_exit(void);
+
+#endif /* CFUSBL_H_ */
diff --git a/net/caif/Kconfig b/net/caif/Kconfig
index 529750d..43cd844 100644
--- a/net/caif/Kconfig
+++ b/net/caif/Kconfig
@@ -40,3 +40,14 @@ config CAIF_NETDEV
If you select to build it as a built-in then the main CAIF device must
also be a built-in.
If unsure say Y.
+
+config CAIF_USB
+ bool "CAIF USB support"
+ depends on CAIF
+ default CAIF
+ ---help---
+ Say Y if you are using CAIF over USB CDC NCM.
+ This can be either built-in or a loadable module,
+ If you select to build it as a built-in then the main CAIF device must
+ also be a built-in.
+ If unsure say N.
diff --git a/net/caif/Makefile b/net/caif/Makefile
index ebcd4e7..3965f73 100644
--- a/net/caif/Makefile
+++ b/net/caif/Makefile
@@ -1,4 +1,5 @@
-ccflags-$(CONFIG_CAIF_DEBUG) := -DDEBUG
+ccflags-$(CONFIG_CAIF_DEBUG) += -DDEBUG
+ccflags-$(CONFIG_CAIF_USB) += -DCAIF_USB
caif-y := caif_dev.o \
cfcnfg.o cfmuxl.o cfctrl.o \
@@ -6,6 +7,7 @@ caif-y := caif_dev.o \
cfserl.o cfdgml.o \
cfrfml.o cfvidl.o cfutill.o \
cfsrvl.o cfpkt_skbuff.o
+caif-$(CONFIG_CAIF_USB) += cfusbl.o
obj-$(CONFIG_CAIF) += caif.o
obj-$(CONFIG_CAIF_NETDEV) += chnl_net.o
diff --git a/net/caif/caif_dev.c b/net/caif/caif_dev.c
index 415353e..6ef0e90 100644
--- a/net/caif/caif_dev.c
+++ b/net/caif/caif_dev.c
@@ -25,6 +25,7 @@
#include <net/caif/cfpkt.h>
#include <net/caif/cfcnfg.h>
#include <net/caif/cfserl.h>
+#include <net/caif/cfusbl.h>
MODULE_LICENSE("GPL");
@@ -506,6 +507,9 @@ static int __init caif_device_init(void)
if (result)
return result;
+#ifdef CAIF_USB
+ cfusbl_init();
+#endif
register_netdevice_notifier(&caif_device_notifier);
dev_add_pack(&caif_packet_type);
@@ -517,6 +521,9 @@ static void __exit caif_device_exit(void)
unregister_pernet_device(&caif_net_ops);
unregister_netdevice_notifier(&caif_device_notifier);
dev_remove_pack(&caif_packet_type);
+#ifdef CAIF_USB
+ cfusbl_exit();
+#endif
}
module_init(caif_device_init);
diff --git a/net/caif/cfusbl.c b/net/caif/cfusbl.c
new file mode 100644
index 0000000..8353a55
--- /dev/null
+++ b/net/caif/cfusbl.c
@@ -0,0 +1,199 @@
+/*
+ * CAIF USB handler
+ * Copyright (C) ST-Ericsson AB 2011
+ * Author: Sjur Brendeland/sjur.brandeland@stericsson.com
+ * License terms: GNU General Public License (GPL) version 2
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
+
+#include <linux/netdevice.h>
+#include <linux/slab.h>
+#include <linux/netdevice.h>
+#include <linux/mii.h>
+#include <linux/usb.h>
+#include <linux/usb/usbnet.h>
+#include <net/netns/generic.h>
+#include <net/caif/caif_dev.h>
+#include <net/caif/caif_layer.h>
+#include <net/caif/cfpkt.h>
+#include <net/caif/cfcnfg.h>
+
+MODULE_LICENSE("GPL");
+
+#define CFUSB_PAD_DESCR_SZ 1 /* Alignment descriptor length */
+#define CFUSB_ALIGNMENT 4 /* Number of bytes to align. */
+#define CFUSB_MAX_HEADLEN (CFUSB_PAD_DESCR_SZ + CFUSB_ALIGNMENT-1)
+#define STE_USB_VID 0x04cc /* USB Product ID for ST-Ericsson */
+#define STE_USB_PID_CAIF 0x2306 /* Product id for CAIF Modems */
+
+struct cfusbl {
+ struct cflayer layer;
+ u8 tx_eth_hdr[ETH_HLEN];
+};
+
+static bool pack_added;
+
+static int cfusbl_receive(struct cflayer *layr, struct cfpkt *pkt)
+{
+ u8 hpad;
+
+ /* Remove padding. */
+ cfpkt_extr_head(pkt, &hpad, 1);
+ cfpkt_extr_head(pkt, NULL, hpad);
+ return layr->up->receive(layr->up, pkt);
+}
+
+static int cfusbl_transmit(struct cflayer *layr, struct cfpkt *pkt)
+{
+ struct caif_payload_info *info;
+ u8 hpad;
+ u8 zeros[CFUSB_ALIGNMENT];
+ struct sk_buff *skb;
+ struct cfusbl *usbl = container_of(layr, struct cfusbl, layer);
+
+ skb = cfpkt_tonative(pkt);
+
+ skb_reset_network_header(skb);
+ skb->protocol = htons(ETH_P_IP);
+
+ info = cfpkt_info(pkt);
+ hpad = (info->hdr_len + CFUSB_PAD_DESCR_SZ) & (CFUSB_ALIGNMENT - 1);
+
+ if (skb_headroom(skb) < ETH_HLEN + CFUSB_PAD_DESCR_SZ + hpad) {
+ pr_warn("Headroom to small\n");
+ kfree_skb(skb);
+ return -EIO;
+ }
+ memset(zeros, 0, hpad);
+
+ cfpkt_add_head(pkt, zeros, hpad);
+ cfpkt_add_head(pkt, &hpad, 1);
+ cfpkt_add_head(pkt, usbl->tx_eth_hdr, sizeof(usbl->tx_eth_hdr));
+ return layr->dn->transmit(layr->dn, pkt);
+}
+
+static void cfusbl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
+ int phyid)
+{
+ if (layr->up && layr->up->ctrlcmd)
+ layr->up->ctrlcmd(layr->up, ctrl, layr->id);
+}
+
+struct cflayer *cfusbl_create(int phyid, u8 ethaddr[ETH_ALEN],
+ u8 braddr[ETH_ALEN])
+{
+ struct cfusbl *this = kmalloc(sizeof(struct cfusbl), GFP_ATOMIC);
+
+ if (!this) {
+ pr_warn("Out of memory\n");
+ return NULL;
+ }
+ caif_assert(offsetof(struct cfusbl, layer) == 0);
+
+ memset(this, 0, sizeof(struct cflayer));
+ this->layer.receive = cfusbl_receive;
+ this->layer.transmit = cfusbl_transmit;
+ this->layer.ctrlcmd = cfusbl_ctrlcmd;
+ snprintf(this->layer.name, CAIF_LAYER_NAME_SZ, "usb%d", phyid);
+ this->layer.id = phyid;
+
+ /*
+ * Construct TX ethernet header:
+ * 0-5 destination address
+ * 5-11 source address
+ * 12-13 protocol type
+ */
+ memcpy(&this->tx_eth_hdr[ETH_ALEN], braddr, ETH_ALEN);
+ memcpy(&this->tx_eth_hdr[ETH_ALEN], ethaddr, ETH_ALEN);
+ this->tx_eth_hdr[12] = cpu_to_be16(ETH_P_802_EX1) & 0xff;
+ this->tx_eth_hdr[13] = (cpu_to_be16(ETH_P_802_EX1) >> 8) & 0xff;
+ pr_debug("caif ethernet TX-header dst:%pM src:%pM type:%02x%02x\n",
+ this->tx_eth_hdr, this->tx_eth_hdr + ETH_ALEN,
+ this->tx_eth_hdr[12], this->tx_eth_hdr[13]);
+
+ return (struct cflayer *) this;
+}
+
+static struct packet_type caif_usb_type __read_mostly = {
+ .type = cpu_to_be16(ETH_P_802_EX1),
+};
+
+static int cfusbl_device_notify(struct notifier_block *me, unsigned long what,
+ void *arg)
+{
+ struct net_device *dev = arg;
+ struct caif_dev_common common;
+ struct cflayer *layer, *link_support;
+ struct usbnet *usbnet = netdev_priv(dev);
+ struct usb_device *usbdev = usbnet->udev;
+ struct ethtool_drvinfo drvinfo;
+
+ if (what != NETDEV_REGISTER)
+ return 0;
+ /*
+ * Quirks: High-jack ethtool to find if we have a NCM device,
+ * and find it's VID/PID.
+ */
+ if (dev->ethtool_ops == NULL || dev->ethtool_ops->get_drvinfo == NULL)
+ return 0;
+
+ dev->ethtool_ops->get_drvinfo(dev, &drvinfo);
+ if (strncmp(drvinfo.driver, "cdc_ncm", 7) != 0)
+ return 0;
+
+ pr_debug("USB CDC NCM device VID:0x%4x PID:0x%4x\n",
+ le16_to_cpu(usbdev->descriptor.idVendor),
+ le16_to_cpu(usbdev->descriptor.idProduct));
+
+ /* Check for VID/PID that supports CAIF */
+ if (!(le16_to_cpu(usbdev->descriptor.idVendor) == STE_USB_VID &&
+ le16_to_cpu(usbdev->descriptor.idProduct) == STE_USB_PID_CAIF))
+ return 0;
+
+ memset(&common, 0, sizeof(common));
+ common.use_frag = false;
+ common.use_fcs = false;
+ common.use_stx = false;
+ common.link_select = CAIF_LINK_HIGH_BANDW;
+ common.flowctrl = NULL;
+
+ link_support = cfusbl_create(dev->ifindex, dev->dev_addr,
+ dev->broadcast);
+ if (!link_support) {
+ pr_warn("Out of memory\n");
+ return -ENOMEM;
+ }
+
+ if (dev->num_tx_queues > 1)
+ pr_warn("USB device uses more than one tx queue\n");
+
+ caif_enroll_dev(dev, &common, link_support, CFUSB_MAX_HEADLEN,
+ &layer, &caif_usb_type.func);
+ if (!pack_added)
+ dev_add_pack(&caif_usb_type);
+ pack_added = 1;
+
+ strncpy(layer->name, dev->name,
+ sizeof(layer->name) - 1);
+ layer->name[sizeof(layer->name) - 1] = 0;
+
+ return 0;
+}
+
+static struct notifier_block caif_device_notifier = {
+ .notifier_call = cfusbl_device_notify,
+ .priority = 0,
+};
+
+void cfusbl_init(void)
+{
+ register_netdevice_notifier(&caif_device_notifier);
+}
+
+void cfusbl_exit(void)
+{
+ unregister_netdevice_notifier(&caif_device_notifier);
+ dev_remove_pack(&caif_usb_type);
+}
--
1.7.0.4
^ permalink raw reply related [flat|nested] 9+ messages in thread