freebsd-skq/sys/dev/ppbus/ppb_base.c
jhb 879505d4df Add locking to ppc and ppbus and mark the whole lot MPSAFE:
- To avoid having a bunch of locks that end up always getting acquired as
  a group, give each ppc(4) device a mutex which it shares with all the
  child devices including ppbus(4), lpt(4), plip(4), etc.  This mutex
  is then used for all the locking.
- Rework the interrupt handling stuff yet again.  Now ppbus drivers setup
  their interrupt handler during attach and tear it down during detach
  like most other drivers.  ppbus(4) only invokes the interrupt handler
  of the device that currently owns the bus (if any) when an interrupt
  occurs, however.  Also, interrupt handlers in general now accept their
  softc pointers as their argument rather than the device_t.  Another
  feature of the ppbus interrupt handlers is that they are called with
  the parent ppc device's lock already held.  This minimizes the number
  of lock operations during an interrupt.
- Mark plip(4), lpt(4), pcfclock(4), ppi(4), vpo(4) MPSAFE.
- lpbb(4) uses the ppc lock instead of Giant.
- Other plip(4) changes:
  - Add a mutex to protect the global tables in plip(4) and free them on
    module unload.
  - Add a detach routine.
  - Split out the init/stop code from the ioctl routine into separate
    functions.
- Other lpt(4) changes:
  - Use device_printf().
  - Use a dedicated callout for the lptout timer.
  - Allocate the I/O buffers at attach and detach rather than during
    open and close as this simplifies the locking at the cost of
    1024+32 bytes when the driver is attached.
- Other ppi(4) changes:
  - Use an sx lock to serialize open and close.
  - Remove unused HADBUS flag.
  - Add a detach routine.
  - Use a malloc'd buffer for each read and write to avoid races with
    concurrent read/write.
- Other pps(4) changes:
  - Use a callout rather than a callout handle with timeout().
  - Conform to the new ppbus requirements (regular mutex, non-filter
    interrupt handler).  pps(4) is probably going to have to become a
    standalone driver that doesn't use ppbus(4) to satisfy it's
    requirements for low latency as a result.
  - Use an sx lock to serialize open and close.
- Other vpo(4) changes:
  - Use the parent ppc device's lock to create the CAM sim instead of
    Giant.
- Other ppc(4) changes:
  - Fix ppc_isa's detach method to detach instead of calling attach.

Tested by:	  no one :-(
2009-01-21 23:10:06 +00:00

261 lines
5.5 KiB
C

/*-
* Copyright (c) 1997, 1998, 1999 Nicolas Souchu
* 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.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, 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 DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <dev/ppbus/ppbconf.h>
#include "ppbus_if.h"
#include <dev/ppbus/ppbio.h>
MODULE_VERSION(ppbus, 1);
#define DEVTOSOFTC(dev) ((struct ppb_data *)device_get_softc(dev))
/*
* ppb_poll_bus()
*
* Polls the bus
*
* max is a delay in 10-milliseconds
*/
int
ppb_poll_bus(device_t bus, int max,
char mask, char status, int how)
{
struct ppb_data *ppb = DEVTOSOFTC(bus);
int i, j, error;
char r;
mtx_assert(ppb->ppc_lock, MA_OWNED);
/* try at least up to 10ms */
for (j = 0; j < ((how & PPB_POLL) ? max : 1); j++) {
for (i = 0; i < 10000; i++) {
r = ppb_rstr(bus);
DELAY(1);
if ((r & mask) == status)
return (0);
}
}
if (!(how & PPB_POLL)) {
for (i = 0; max == PPB_FOREVER || i < max-1; i++) {
if ((ppb_rstr(bus) & mask) == status)
return (0);
/* wait 10 ms */
error = mtx_sleep((caddr_t)bus, ppb->ppc_lock, PPBPRI |
(how == PPB_NOINTR ? 0 : PCATCH), "ppbpoll", hz/100);
if (error != EWOULDBLOCK)
return (error);
}
}
return (EWOULDBLOCK);
}
/*
* ppb_get_epp_protocol()
*
* Return the chipset EPP protocol
*/
int
ppb_get_epp_protocol(device_t bus)
{
#ifdef INVARIANTS
struct ppb_data *ppb = DEVTOSOFTC(bus);
#endif
uintptr_t protocol;
mtx_assert(ppb->ppc_lock, MA_OWNED);
BUS_READ_IVAR(device_get_parent(bus), bus, PPC_IVAR_EPP_PROTO, &protocol);
return (protocol);
}
/*
* ppb_get_mode()
*
*/
int
ppb_get_mode(device_t bus)
{
struct ppb_data *ppb = DEVTOSOFTC(bus);
/* XXX yet device mode = ppbus mode = chipset mode */
mtx_assert(ppb->ppc_lock, MA_OWNED);
return (ppb->mode);
}
/*
* ppb_set_mode()
*
* Set the operating mode of the chipset, return the previous mode
*/
int
ppb_set_mode(device_t bus, int mode)
{
struct ppb_data *ppb = DEVTOSOFTC(bus);
int old_mode = ppb_get_mode(bus);
mtx_assert(ppb->ppc_lock, MA_OWNED);
if (PPBUS_SETMODE(device_get_parent(bus), mode))
return (-1);
/* XXX yet device mode = ppbus mode = chipset mode */
ppb->mode = (mode & PPB_MASK);
return (old_mode);
}
/*
* ppb_write()
*
* Write charaters to the port
*/
int
ppb_write(device_t bus, char *buf, int len, int how)
{
#ifdef INVARIANTS
struct ppb_data *ppb = DEVTOSOFTC(bus);
#endif
mtx_assert(ppb->ppc_lock, MA_OWNED);
return (PPBUS_WRITE(device_get_parent(bus), buf, len, how));
}
/*
* ppb_reset_epp_timeout()
*
* Reset the EPP timeout bit in the status register
*/
int
ppb_reset_epp_timeout(device_t bus)
{
#ifdef INVARIANTS
struct ppb_data *ppb = DEVTOSOFTC(bus);
#endif
mtx_assert(ppb->ppc_lock, MA_OWNED);
return(PPBUS_RESET_EPP(device_get_parent(bus)));
}
/*
* ppb_ecp_sync()
*
* Wait for the ECP FIFO to be empty
*/
int
ppb_ecp_sync(device_t bus)
{
#ifdef INVARIANTS
struct ppb_data *ppb = DEVTOSOFTC(bus);
#endif
mtx_assert(ppb->ppc_lock, MA_OWNED);
return (PPBUS_ECP_SYNC(device_get_parent(bus)));
}
/*
* ppb_get_status()
*
* Read the status register and update the status info
*/
int
ppb_get_status(device_t bus, struct ppb_status *status)
{
#ifdef INVARIANTS
struct ppb_data *ppb = DEVTOSOFTC(bus);
#endif
register char r;
mtx_assert(ppb->ppc_lock, MA_OWNED);
r = status->status = ppb_rstr(bus);
status->timeout = r & TIMEOUT;
status->error = !(r & nFAULT);
status->select = r & SELECT;
status->paper_end = r & PERROR;
status->ack = !(r & nACK);
status->busy = !(r & nBUSY);
return (0);
}
void
ppb_lock(device_t bus)
{
struct ppb_data *ppb = DEVTOSOFTC(bus);
mtx_lock(ppb->ppc_lock);
}
void
ppb_unlock(device_t bus)
{
struct ppb_data *ppb = DEVTOSOFTC(bus);
mtx_unlock(ppb->ppc_lock);
}
void
_ppb_assert_locked(device_t bus, const char *file, int line)
{
#ifdef INVARIANTS
struct ppb_data *ppb = DEVTOSOFTC(bus);
_mtx_assert(ppb->ppc_lock, MA_OWNED, file, line);
#endif
}
void
ppb_init_callout(device_t bus, struct callout *c, int flags)
{
struct ppb_data *ppb = DEVTOSOFTC(bus);
callout_init_mtx(c, ppb->ppc_lock, flags);
}
int
ppb_sleep(device_t bus, void *wchan, int priority, const char *wmesg, int timo)
{
struct ppb_data *ppb = DEVTOSOFTC(bus);
return (mtx_sleep(wchan, ppb->ppc_lock, priority, wmesg, timo));
}