linux/drivers/net/ixp2000/ixpdev.h

30 lines
762 B
C
Raw Normal View History

[PATCH] intel ixp2000 network driver The way the hardware and firmware work is that there is one shared RX queue and IRQ for a number of different network interfaces. Due to this, we would like to process received packets for every interface in the same NAPI poll handler, so we need a pseudo-device to schedule polling on. What the driver currently does is that it always schedules polling for the first network interface in the list, and processes packets for every interface in the poll handler for that first interface -- however, this scheme breaks down if the first network interface happens to not be up, since netif_rx_schedule_prep() checks netif_running(). sky2 apparently has the same issue, and Stephen Hemminger suggested a way to work around this: create a variant of netif_rx_schedule_prep() that does not check netif_running(). I implemented this locally and called it netif_rx_schedule_prep_notup(), and it seems to work well, but it's something that probably not everyone would be happy with. The ixp2000 is an ARM CPU with a high-speed network interface in the CPU itself (full duplex 4Gb/s or 10Gb/s depending on the IXP model.) The CPU package also contains 8 or 16 (again depending on the IXP model) 'microengines', which are somewhat primitive but very fast and efficient processor cores which can be used to offload various things from the main CPU. This driver makes the high-speed network interface in the CPU visible and usable as a regular linux network device. Currently, it only supports the Radisys ENP2611 IXP board, but adding support for other board types should be fairly easy. Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2005-11-12 01:23:13 +08:00
/*
* IXP2000 MSF network device driver
* Copyright (C) 2004, 2005 Lennert Buytenhek <buytenh@wantstofly.org>
* Dedicated to Marija Kulikova.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#ifndef __IXPDEV_H
#define __IXPDEV_H
struct ixpdev_priv
{
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-04 07:41:36 +08:00
struct net_device *dev;
struct napi_struct napi;
[PATCH] intel ixp2000 network driver The way the hardware and firmware work is that there is one shared RX queue and IRQ for a number of different network interfaces. Due to this, we would like to process received packets for every interface in the same NAPI poll handler, so we need a pseudo-device to schedule polling on. What the driver currently does is that it always schedules polling for the first network interface in the list, and processes packets for every interface in the poll handler for that first interface -- however, this scheme breaks down if the first network interface happens to not be up, since netif_rx_schedule_prep() checks netif_running(). sky2 apparently has the same issue, and Stephen Hemminger suggested a way to work around this: create a variant of netif_rx_schedule_prep() that does not check netif_running(). I implemented this locally and called it netif_rx_schedule_prep_notup(), and it seems to work well, but it's something that probably not everyone would be happy with. The ixp2000 is an ARM CPU with a high-speed network interface in the CPU itself (full duplex 4Gb/s or 10Gb/s depending on the IXP model.) The CPU package also contains 8 or 16 (again depending on the IXP model) 'microengines', which are somewhat primitive but very fast and efficient processor cores which can be used to offload various things from the main CPU. This driver makes the high-speed network interface in the CPU visible and usable as a regular linux network device. Currently, it only supports the Radisys ENP2611 IXP board, but adding support for other board types should be fairly easy. Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2005-11-12 01:23:13 +08:00
int channel;
int tx_queue_entries;
};
struct net_device *ixpdev_alloc(int channel, int sizeof_priv);
int ixpdev_init(int num_ports, struct net_device **nds,
void (*set_port_admin_status)(int port, int up));
void ixpdev_deinit(void);
#endif