int
tpm_getburst(struct tpm_softc *sc)
{
int burst, to, rv;
to = tpm_tmotohz(TPM_BURST_TMO);
burst = 0;
while (burst == 0 && to--) {
/*
* Burst count has to be read from bits 8 to 23 without
* touching any other bits, eg. the actual status bits 0
* to 7.
*/
burst = bus_space_read_1(sc->sc_bt, sc->sc_bh, TPM_STS + 1);
burst |= bus_space_read_1(sc->sc_bt, sc->sc_bh, TPM_STS + 2)
<< 8;
#ifdef TPM_DEBUG
printf("tpm_getburst: read %d\n", burst);
#endif
if (burst)
return burst;
rv = tsleep(sc, PRIBIO | PCATCH, "tpm_getburst", 1);
if (rv && rv != EWOULDBLOCK) {
return 0;
}
}
return 0;
}
int
tpm_request_locality(struct tpm_softc *sc, int l)
{
uint32_t r;
int to, rv;
if (l != 0)
return EINVAL;
if ((bus_space_read_1(sc->sc_bt, sc->sc_bh, TPM_ACCESS) &
(TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY)) ==
(TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY))
return 0;
bus_space_write_1(sc->sc_bt, sc->sc_bh, TPM_ACCESS,
TPM_ACCESS_REQUEST_USE);
to = tpm_tmotohz(TPM_ACCESS_TMO);
while ((r = bus_space_read_1(sc->sc_bt, sc->sc_bh, TPM_ACCESS) &
(TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY)) !=
(TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY) && to--) {
rv = tsleep(sc->sc_init, PRIBIO | PCATCH, "tpm_locality", 1);
if (rv && rv != EWOULDBLOCK) {
#ifdef TPM_DEBUG
aprint_debug_dev(sc->sc_dev, "%s: interrupted %d\n",
__func__, rv);
#endif
return rv;
}
}
if ((r & (TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY)) !=
(TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY)) {
#ifdef TPM_DEBUG
char buf[128];
snprintb(buf, sizeof(buf), TPM_ACCESS_BITS, r);
aprint_debug_dev(sc->sc_dev, "%s: access %s\n", __func__, buf);
#endif
return EBUSY;
}
return 0;
}
int
tpm_request_locality(struct tpm_softc *sc, int l)
{
u_int32_t r;
int to, rv;
if (l != 0)
return EINVAL;
if ((bus_space_read_1(sc->sc_bt, sc->sc_bh, TPM_ACCESS) &
(TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY)) ==
(TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY))
return 0;
bus_space_write_1(sc->sc_bt, sc->sc_bh, TPM_ACCESS,
TPM_ACCESS_REQUEST_USE);
to = tpm_tmotohz(TPM_ACCESS_TMO);
while ((r = bus_space_read_1(sc->sc_bt, sc->sc_bh, TPM_ACCESS) &
(TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY)) !=
(TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY) && to--) {
rv = tsleep(sc->sc_init, PRIBIO | PCATCH, "tpm_locality", 1);
if (rv && rv != EWOULDBLOCK) {
#ifdef TPM_DEBUG
printf("tpm_request_locality: interrupted %d\n", rv);
#endif
return rv;
}
}
if ((r & (TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY)) !=
(TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY)) {
#ifdef TPM_DEBUG
printf("tpm_request_locality: access %b\n", r, TPM_ACCESS_BITS);
#endif
return EBUSY;
}
return 0;
}
/*
* Wait on given status bits, uses interrupts where possible, otherwise polls.
*/
int
tpm_waitfor(struct tpm_softc *sc, u_int8_t b0, int tmo, void *c)
{
u_int8_t b;
int re, to, rv;
#ifdef TPM_DEBUG
printf("tpm_waitfor: b0 %b\n", b0, TPM_STS_BITS);
#endif
/*
* If possible, use interrupts, otherwise poll.
*
* We use interrupts for TPM_STS_VALID and TPM_STS_DATA_AVAIL (if
* the tpm chips supports them) as waiting for those can take
* really long. The other TPM_STS* are not needed very often
* so we do not support them.
*/
if (sc->sc_vector != IRQUNK) {
b = b0;
/*
* Wait for data ready. This interrupt only occures
* when both TPM_STS_VALID and TPM_STS_DATA_AVAIL are asserted.
* Thus we don't have to bother with TPM_STS_VALID
* separately and can just return.
*
* This only holds for interrupts! When using polling
* both flags have to be waited for, see below.
*/
if ((b & TPM_STS_DATA_AVAIL) && (sc->sc_capabilities &
TPM_INTF_DATA_AVAIL_INT))
return tpm_waitfor_int(sc, b, tmo, c,
TPM_DATA_AVAIL_INT);
/* Wait for status valid bit. */
if ((b & TPM_STS_VALID) && (sc->sc_capabilities &
TPM_INTF_STS_VALID_INT)) {
rv = tpm_waitfor_int(sc, b, tmo, c, TPM_STS_VALID_INT);
if (rv != 0)
return rv;
else
b = b0 & ~TPM_STS_VALID;
}
/*
* When all flags are taken care of, return. Otherwise
* use polling for eg. TPM_STS_CMD_READY.
*/
if (b == 0)
return 0;
}
re = 3;
restart:
/*
* If requested wait for TPM_STS_VALID before dealing with
* any other flag. Eg. when both TPM_STS_DATA_AVAIL and TPM_STS_VALID
* are requested, wait for the latter first.
*/
b = b0;
if (b0 & TPM_STS_VALID)
b = TPM_STS_VALID;
to = tpm_tmotohz(tmo);
again:
if ((rv = tpm_waitfor_poll(sc, b, to, c)) != 0)
return rv;
if ((b & sc->sc_stat) == TPM_STS_VALID) {
/* Now wait for other flags. */
b = b0 & ~TPM_STS_VALID;
to++;
goto again;
}
if ((sc->sc_stat & b) != b) {
#ifdef TPM_DEBUG
printf("tpm_waitfor: timeout: stat=%b b=%b\n",
sc->sc_stat, TPM_STS_BITS, b, TPM_STS_BITS);
#endif
if (re-- && (b0 & TPM_STS_VALID)) {
bus_space_write_1(sc->sc_bt, sc->sc_bh, TPM_STS,
TPM_STS_RESP_RETRY);
goto restart;
}
return EIO;
}
return 0;
}
/* Wait for given status bits using interrupts. */
int
tpm_waitfor_int(struct tpm_softc *sc, u_int8_t mask, int tmo, void *c,
int inttype)
{
int rv, to;
/* Poll and return when condition is already met. */
sc->sc_stat = tpm_status(sc);
if ((sc->sc_stat & mask) == mask)
return 0;
/*
* Enable interrupt on tpm chip. Note that interrupts on our
* level (SPL_TTY) are disabled (see tpm{read,write} et al) and
* will not be delivered to the cpu until we call tsleep(9) below.
*/
bus_space_write_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE,
bus_space_read_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE) |
inttype);
bus_space_write_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE,
bus_space_read_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE) |
TPM_GLOBAL_INT_ENABLE);
/*
* Poll once more to remedy the race between previous polling
* and enabling interrupts on the tpm chip.
*/
sc->sc_stat = tpm_status(sc);
if ((sc->sc_stat & mask) == mask) {
rv = 0;
goto out;
}
to = tpm_tmotohz(tmo);
#ifdef TPM_DEBUG
printf("tpm_waitfor_int: sleeping for %d ticks on %p\n", to, c);
#endif
/*
* tsleep(9) enables interrupts on the cpu and returns after
* wake up with interrupts disabled again. Note that interrupts
* generated by the tpm chip while being at SPL_TTY are not lost
* but held and delivered as soon as the cpu goes below SPL_TTY.
*/
rv = tsleep(c, PRIBIO | PCATCH, "tpm_intr", to);
sc->sc_stat = tpm_status(sc);
#ifdef TPM_DEBUG
printf("tpm_waitfor_int: woke up with rv %d stat %b\n", rv,
sc->sc_stat, TPM_STS_BITS);
#endif
if ((sc->sc_stat & mask) == mask)
rv = 0;
/* Disable interrupts on tpm chip again. */
out: bus_space_write_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE,
bus_space_read_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE) &
~TPM_GLOBAL_INT_ENABLE);
bus_space_write_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE,
bus_space_read_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE) &
~inttype);
return rv;
}
