d/freebsd-nq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Rename two functions to make their purpose clearer. Add tons of comments.

Browse Source 
Generated code is identical after stripping .comment section.

Suggested by:	Andriy Gapon <avg@icyb.net.ua>
MFC after:	2 weeks
This commit is contained in:
Dag-Erling Smørgrav 2009-03-19 12:39:13 +00:00
parent 1214222676
commit 5f9672e15d
1 changed files with 56 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

63
sys/dev/ichwd/ichwd.c
View File

@ -141,26 +141,55 @@ static devclass_t ichwd_devclass;
device_printf(dev, __VA_ARGS__);\
} while (0)
/*
* Disable the watchdog timeout SMI handler.
*
* Apparently, some BIOSes install handlers that reset or disable the
* watchdog timer instead of resetting the system, so we disable the SMI
* (by clearing the SMI_TCO_EN bit of the SMI_EN register) to prevent this
* from happening.
*/
static __inline void
ichwd_intr_enable(struct ichwd_softc *sc)
ichwd_smi_disable(struct ichwd_softc *sc)
{
ichwd_write_smi_4(sc, SMI_EN, ichwd_read_smi_4(sc, SMI_EN) & ~SMI_TCO_EN);
}
/*
* Enable the watchdog timeout SMI handler. See above for details.
*/
static __inline void
ichwd_intr_disable(struct ichwd_softc *sc)
ichwd_smi_enable(struct ichwd_softc *sc)
{
ichwd_write_smi_4(sc, SMI_EN, ichwd_read_smi_4(sc, SMI_EN) | SMI_TCO_EN);
}
/*
* Reset the watchdog status bits.
*/
static __inline void
ichwd_sts_reset(struct ichwd_softc *sc)
{
/*
* The watchdog status bits are set to 1 by the hardware to
* indicate various conditions. They can be cleared by software
* by writing a 1, not a 0.
*/
ichwd_write_tco_2(sc, TCO1_STS, TCO_TIMEOUT);
/*
* XXX The datasheet says that TCO_SECOND_TO_STS must be cleared
* before TCO_BOOT_STS, not the other way around.
*/
ichwd_write_tco_2(sc, TCO2_STS, TCO_BOOT_STS);
ichwd_write_tco_2(sc, TCO2_STS, TCO_SECOND_TO_STS);
}
/*
* Enable the watchdog timer by clearing the TCO_TMR_HALT bit in the
* TCO1_CNT register. This is complicated by the need to preserve bit 9
* of that same register, and the requirement that all other bits must be
* written back as zero.
*/
static __inline void
ichwd_tmr_enable(struct ichwd_softc *sc)
{
@ -172,6 +201,9 @@ ichwd_tmr_enable(struct ichwd_softc *sc)
ichwd_verbose_printf(sc->device, "timer enabled\n");
}
/*
* Disable the watchdog timer. See above for details.
*/
static __inline void
ichwd_tmr_disable(struct ichwd_softc *sc)
{
@ -183,6 +215,11 @@ ichwd_tmr_disable(struct ichwd_softc *sc)
ichwd_verbose_printf(sc->device, "timer disabled\n");
}
/*
* Reload the watchdog timer: writing anything to any of the lower five
* bits of the TCO_RLD register reloads the timer from the last value
* written to TCO_TMR.
*/
static __inline void
ichwd_tmr_reload(struct ichwd_softc *sc)
{
@ -194,6 +231,10 @@ ichwd_tmr_reload(struct ichwd_softc *sc)
ichwd_verbose_printf(sc->device, "timer reloaded\n");
}
/*
* Set the initial timeout value. Note that this must always be followed
* by a reload.
*/
static __inline void
ichwd_tmr_set(struct ichwd_softc *sc, unsigned int timeout)
{
@ -262,7 +303,8 @@ ichwd_clear_noreboot(struct ichwd_softc *sc)
}
/*
* Watchdog event handler.
* Watchdog event handler - called by the framework to enable or disable
* the watchdog or change the initial timeout value.
*/
static void
ichwd_event(void *arg, unsigned int cmd, int *error)
@ -426,6 +468,13 @@ ichwd_attach(device_t dev)
device_printf(dev, "%s (ICH%d or equivalent)\n",
device_get_desc(dev), sc->ich_version);
/*
* XXX we should check the status registers (specifically, the
* TCO_SECOND_TO_STS bit in the TCO2_STS register) to see if we
* just came back from a watchdog-induced reset, and let the user
* know.
*/
/* reset the watchdog status registers */
ichwd_sts_reset(sc);
@ -435,8 +484,8 @@ ichwd_attach(device_t dev)
/* register the watchdog event handler */
sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, ichwd_event, sc, 0);
/* enable watchdog timeout interrupts */
ichwd_intr_enable(sc);
/* disable the SMI handler */
ichwd_smi_disable(sc);
return (0);
fail:
@ -466,8 +515,8 @@ ichwd_detach(device_t dev)
if (sc->active)
ichwd_tmr_disable(sc);
/* disable watchdog timeout interrupts */
ichwd_intr_disable(sc);
/* enable the SMI handler */
ichwd_smi_enable(sc);
/* deregister event handler */
if (sc->ev_tag != NULL)