freebsd-skq/sys/dev/ath/if_ath_ahb.c
Adrian Chadd 1b5c5f5ad0 I give up - introduce a TX lock to serialise TX operations.
I've tried serialising TX using queues and such but unfortunately
due to how this interacts with the locking going on elsewhere in the
networking stack, the TX task gets delayed, resulting in quite a
noticable throughput loss:

* baseline TCP for 2x2 11n HT40 is ~ 170mbit/sec;
* TCP for TX task in the ath taskq, with the RX also going on - 80mbit/sec;
* TCP for TX task in a separate, second taskq - 100mbit/sec.

So for now I'm going with the Linux wireless stack approach - lock tx
early.  The linux code does in the wireless stack, before the 802.11
state stuff happens and before it's punted to the driver.
But TX locking needs to also occur at the driver layer as the TX
completion code _also_ begins to drain the ifnet TX queue.

Whilst I'm here, add some KTR traces for the TX path.

Note:

* This really should be done at the net80211 layer (as well, at least.)
  But that'll have to wait for a little more thought to happen.
2012-10-31 06:27:58 +00:00

306 lines
8.2 KiB
C

/*-
* Copyright (c) 2002-2008 Sam Leffler, Errno Consulting
* Copyright (c) 2010-2011 Adrian Chadd, Xenion Pty Ltd
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
* redistribution must be conditioned upon including a substantially
* similar Disclaimer requirement for further binary redistribution.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
* OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
* IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGES.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* AHB bus front-end for the Atheros Wireless LAN controller driver.
*/
#include "opt_ath.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/module.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/errno.h>
#include <machine/bus.h>
#include <machine/resource.h>
#include <sys/bus.h>
#include <sys/rman.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/if_media.h>
#include <net/if_arp.h>
#include <net80211/ieee80211_var.h>
#include <dev/ath/if_athvar.h>
#include <mips/atheros/ar71xxreg.h>
#include <mips/atheros/ar91xxreg.h>
#include <mips/atheros/ar71xx_cpudef.h>
/*
* bus glue.
*/
/* number of 16 bit words */
#define ATH_EEPROM_DATA_SIZE 2048
struct ath_ahb_softc {
struct ath_softc sc_sc;
struct resource *sc_sr; /* memory resource */
struct resource *sc_irq; /* irq resource */
struct resource *sc_eeprom; /* eeprom location */
void *sc_ih; /* interrupt handler */
};
#define VENDOR_ATHEROS 0x168c
#define AR9130_DEVID 0x000b
static int
ath_ahb_probe(device_t dev)
{
const char* devname;
/* Atheros / ar9130 */
devname = ath_hal_probe(VENDOR_ATHEROS, AR9130_DEVID);
if (devname != NULL) {
device_set_desc(dev, devname);
return BUS_PROBE_DEFAULT;
}
return ENXIO;
}
static int
ath_ahb_attach(device_t dev)
{
struct ath_ahb_softc *psc = device_get_softc(dev);
struct ath_softc *sc = &psc->sc_sc;
int error = ENXIO;
int rid;
long eepromaddr;
uint8_t *p;
sc->sc_dev = dev;
rid = 0;
psc->sc_sr = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
if (psc->sc_sr == NULL) {
device_printf(dev, "cannot map register space\n");
goto bad;
}
if (resource_long_value(device_get_name(dev), device_get_unit(dev),
"eepromaddr", &eepromaddr) != 0) {
device_printf(dev, "cannot fetch 'eepromaddr' from hints\n");
goto bad0;
}
rid = 0;
device_printf(sc->sc_dev, "eeprom @ %p\n", (void *) eepromaddr);
psc->sc_eeprom = bus_alloc_resource(dev, SYS_RES_MEMORY, &rid, (uintptr_t) eepromaddr,
(uintptr_t) eepromaddr + (uintptr_t) ((ATH_EEPROM_DATA_SIZE * 2) - 1), 0, RF_ACTIVE);
if (psc->sc_eeprom == NULL) {
device_printf(dev, "cannot map eeprom space\n");
goto bad0;
}
/* XXX uintptr_t is a bandaid for ia64; to be fixed */
sc->sc_st = (HAL_BUS_TAG)(uintptr_t) rman_get_bustag(psc->sc_sr);
sc->sc_sh = (HAL_BUS_HANDLE) rman_get_bushandle(psc->sc_sr);
/*
* Mark device invalid so any interrupts (shared or otherwise)
* that arrive before the HAL is setup are discarded.
*/
sc->sc_invalid = 1;
/* Copy the EEPROM data out */
sc->sc_eepromdata = malloc(ATH_EEPROM_DATA_SIZE * 2, M_TEMP, M_NOWAIT | M_ZERO);
if (sc->sc_eepromdata == NULL) {
device_printf(dev, "cannot allocate memory for eeprom data\n");
goto bad1;
}
device_printf(sc->sc_dev, "eeprom data @ %p\n", (void *) rman_get_bushandle(psc->sc_eeprom));
/* XXX why doesn't this work? -adrian */
#if 0
bus_space_read_multi_1(
rman_get_bustag(psc->sc_eeprom),
rman_get_bushandle(psc->sc_eeprom),
0, (u_int8_t *) sc->sc_eepromdata, ATH_EEPROM_DATA_SIZE * 2);
#endif
p = (void *) rman_get_bushandle(psc->sc_eeprom);
memcpy(sc->sc_eepromdata, p, ATH_EEPROM_DATA_SIZE * 2);
/*
* Arrange interrupt line.
*/
rid = 0;
psc->sc_irq = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, RF_SHAREABLE|RF_ACTIVE);
if (psc->sc_irq == NULL) {
device_printf(dev, "could not map interrupt\n");
goto bad1;
}
if (bus_setup_intr(dev, psc->sc_irq,
INTR_TYPE_NET | INTR_MPSAFE,
NULL, ath_intr, sc, &psc->sc_ih)) {
device_printf(dev, "could not establish interrupt\n");
goto bad2;
}
/*
* Setup DMA descriptor area.
*/
if (bus_dma_tag_create(bus_get_dma_tag(dev), /* parent */
1, 0, /* alignment, bounds */
BUS_SPACE_MAXADDR_32BIT, /* lowaddr */
BUS_SPACE_MAXADDR, /* highaddr */
NULL, NULL, /* filter, filterarg */
0x3ffff, /* maxsize XXX */
ATH_MAX_SCATTER, /* nsegments */
0x3ffff, /* maxsegsize XXX */
BUS_DMA_ALLOCNOW, /* flags */
NULL, /* lockfunc */
NULL, /* lockarg */
&sc->sc_dmat)) {
device_printf(dev, "cannot allocate DMA tag\n");
goto bad3;
}
ATH_LOCK_INIT(sc);
ATH_PCU_LOCK_INIT(sc);
ATH_RX_LOCK_INIT(sc);
ATH_TX_LOCK_INIT(sc);
ATH_TXSTATUS_LOCK_INIT(sc);
error = ath_attach(AR9130_DEVID, sc);
if (error == 0) /* success */
return 0;
ATH_TXSTATUS_LOCK_DESTROY(sc);
ATH_RX_LOCK_DESTROY(sc);
ATH_TX_LOCK_DESTROY(sc);
ATH_PCU_LOCK_DESTROY(sc);
ATH_LOCK_DESTROY(sc);
bus_dma_tag_destroy(sc->sc_dmat);
bad3:
bus_teardown_intr(dev, psc->sc_irq, psc->sc_ih);
bad2:
bus_release_resource(dev, SYS_RES_IRQ, 0, psc->sc_irq);
bad1:
bus_release_resource(dev, SYS_RES_MEMORY, 0, psc->sc_eeprom);
bad0:
bus_release_resource(dev, SYS_RES_MEMORY, 0, psc->sc_sr);
bad:
/* XXX?! */
if (sc->sc_eepromdata)
free(sc->sc_eepromdata, M_TEMP);
return (error);
}
static int
ath_ahb_detach(device_t dev)
{
struct ath_ahb_softc *psc = device_get_softc(dev);
struct ath_softc *sc = &psc->sc_sc;
/* check if device was removed */
sc->sc_invalid = !bus_child_present(dev);
ath_detach(sc);
bus_generic_detach(dev);
bus_teardown_intr(dev, psc->sc_irq, psc->sc_ih);
bus_release_resource(dev, SYS_RES_IRQ, 0, psc->sc_irq);
bus_dma_tag_destroy(sc->sc_dmat);
bus_release_resource(dev, SYS_RES_MEMORY, 0, psc->sc_sr);
bus_release_resource(dev, SYS_RES_MEMORY, 0, psc->sc_eeprom);
/* XXX?! */
if (sc->sc_eepromdata)
free(sc->sc_eepromdata, M_TEMP);
ATH_TXSTATUS_LOCK_DESTROY(sc);
ATH_RX_LOCK_DESTROY(sc);
ATH_TX_LOCK_DESTROY(sc);
ATH_PCU_LOCK_DESTROY(sc);
ATH_LOCK_DESTROY(sc);
return (0);
}
static int
ath_ahb_shutdown(device_t dev)
{
struct ath_ahb_softc *psc = device_get_softc(dev);
ath_shutdown(&psc->sc_sc);
return (0);
}
static int
ath_ahb_suspend(device_t dev)
{
struct ath_ahb_softc *psc = device_get_softc(dev);
ath_suspend(&psc->sc_sc);
return (0);
}
static int
ath_ahb_resume(device_t dev)
{
struct ath_ahb_softc *psc = device_get_softc(dev);
ath_resume(&psc->sc_sc);
return (0);
}
static device_method_t ath_ahb_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, ath_ahb_probe),
DEVMETHOD(device_attach, ath_ahb_attach),
DEVMETHOD(device_detach, ath_ahb_detach),
DEVMETHOD(device_shutdown, ath_ahb_shutdown),
DEVMETHOD(device_suspend, ath_ahb_suspend),
DEVMETHOD(device_resume, ath_ahb_resume),
{ 0,0 }
};
static driver_t ath_ahb_driver = {
"ath",
ath_ahb_methods,
sizeof (struct ath_ahb_softc)
};
static devclass_t ath_devclass;
DRIVER_MODULE(ath, nexus, ath_ahb_driver, ath_devclass, 0, 0);
MODULE_VERSION(ath, 1);
MODULE_DEPEND(ath, wlan, 1, 1, 1); /* 802.11 media layer */
MODULE_DEPEND(ath, if_ath, 1, 1, 1); /* if_ath driver */