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

Add support to the imx watchdog for the FDT "timeout-sec" property, by

Browse Source 
automatically initializing the watchdog using the given value.  Also,
attach at BUS_PASS_TIMER to extend watchdog protection to more of the
kernel init process.
This commit is contained in:
Ian Lepore 2018-07-07 19:10:00 +00:00
parent a4db01f7c6
commit 31ff8defe3
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=336073
1 changed files with 47 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

69
sys/arm/freescale/imx/imx_wdog.c
View File

@ -98,42 +98,52 @@ WR2(struct imx_wdog_softc *sc, bus_size_t offs, uint16_t val)
bus_write_2(sc->sc_res[MEMRES], offs, val);
}
static int
imx_wdog_enable(struct imx_wdog_softc *sc, u_int timeout)
{
uint16_t reg;
if (timeout < 1 || timeout > 128)
return (EINVAL);
mtx_lock(&sc->sc_mtx);
if (timeout != sc->sc_timeout) {
sc->sc_timeout = timeout;
reg = RD2(sc, WDOG_CR_REG);
reg &= ~WDOG_CR_WT_MASK;
reg |= ((2 * timeout - 1) << WDOG_CR_WT_SHIFT);
WR2(sc, WDOG_CR_REG, reg | WDOG_CR_WDE);
}
/* Refresh counter */
WR2(sc, WDOG_SR_REG, WDOG_SR_STEP1);
WR2(sc, WDOG_SR_REG, WDOG_SR_STEP2);
/* Watchdog active, can disable rom-boot watchdog. */
if (sc->sc_pde_enabled) {
sc->sc_pde_enabled = false;
reg = RD2(sc, WDOG_MCR_REG);
WR2(sc, WDOG_MCR_REG, reg & ~WDOG_MCR_PDE);
}
mtx_unlock(&sc->sc_mtx);
return (0);
}
static void
imx_watchdog(void *arg, u_int cmd, int *error)
{
struct imx_wdog_softc *sc;
uint16_t reg;
u_int timeout;
sc = arg;
mtx_lock(&sc->sc_mtx);
if (cmd == 0) {
if (bootverbose)
device_printf(sc->sc_dev, "Can not be disabled.\n");
*error = EOPNOTSUPP;
} else {
timeout = (u_int)((1ULL << (cmd & WD_INTERVAL)) / 1000000000U);
if (timeout > 1 && timeout < 128) {
if (timeout != sc->sc_timeout) {
sc->sc_timeout = timeout;
reg = RD2(sc, WDOG_CR_REG);
reg &= ~WDOG_CR_WT_MASK;
reg |= ((2 * timeout - 1) << WDOG_CR_WT_SHIFT);
WR2(sc, WDOG_CR_REG, reg | WDOG_CR_WDE);
}
/* Refresh counter */
WR2(sc, WDOG_SR_REG, WDOG_SR_STEP1);
WR2(sc, WDOG_SR_REG, WDOG_SR_STEP2);
/* Watchdog active, can disable rom-boot watchdog. */
if (sc->sc_pde_enabled) {
sc->sc_pde_enabled = false;
reg = RD2(sc, WDOG_MCR_REG);
WR2(sc, WDOG_MCR_REG, reg & ~WDOG_MCR_PDE);
}
if (imx_wdog_enable(sc, timeout) == 0)
*error = 0;
}
}
mtx_unlock(&sc->sc_mtx);
}
static int
@ -175,6 +185,7 @@ static int
imx_wdog_attach(device_t dev)
{
struct imx_wdog_softc *sc;
pcell_t timeout;
sc = device_get_softc(dev);
sc->sc_dev = dev;
@ -209,6 +220,19 @@ imx_wdog_attach(device_t dev)
EVENTHANDLER_REGISTER(watchdog_list, imx_watchdog, sc, 0);
/* If there is a timeout-sec property, activate the watchdog. */
if (OF_getencprop(ofw_bus_get_node(sc->sc_dev), "timeout-sec",
&timeout, sizeof(timeout)) == sizeof(timeout)) {
if (timeout < 1 || timeout > 128) {
device_printf(sc->sc_dev, "ERROR: bad timeout-sec "
"property value %u, using 128\n", timeout);
timeout = 128;
}
imx_wdog_enable(sc, timeout);
device_printf(sc->sc_dev, "watchdog enabled using "
"timeout-sec property value %u\n", timeout);
}
/*
* The watchdog hardware cannot be disabled, so there's little point in
* coding up a detach() routine to carefully tear everything down, just
@ -232,5 +256,6 @@ static driver_t imx_wdog_driver = {
static devclass_t imx_wdog_devclass;
DRIVER_MODULE(imx_wdog, simplebus, imx_wdog_driver, imx_wdog_devclass, 0, 0);
EARLY_DRIVER_MODULE(imx_wdog, simplebus, imx_wdog_driver,
imx_wdog_devclass, 0, 0, BUS_PASS_TIMER);
SIMPLEBUS_PNP_INFO(compat_data);