/*
* Wait for about n microseconds (at least!).
*/
void
DELAY(int n)
{
uint32_t cur, last, delta, usecs;
/*
* This works by polling the timer and counting the number of
* microseconds that go by.
*/
last = mips_rd_count();
delta = usecs = 0;
while (n > usecs) {
cur = mips_rd_count();
/* Check to see if the timer has wrapped around. */
if (cur < last)
delta += cur + (0xffffffff - last) + 1;
else
delta += cur - last;
last = cur;
if (delta >= cycles_per_usec) {
usecs += delta / cycles_per_usec;
delta %= cycles_per_usec;
}
}
}
static uint64_t
malta_cpu_freq(void)
{
uint64_t platform_counter_freq = 0;
#if defined(TICK_USE_YAMON_FREQ)
/*
* If we are running on a board which uses YAMON firmware,
* then query CPU pipeline clock from the syscon object.
* If unsuccessful, use hard-coded default.
*/
platform_counter_freq = yamon_getcpufreq();
#elif defined(TICK_USE_MALTA_RTC)
/*
* If we are running on a board with the MC146818 RTC,
* use it to determine CPU pipeline clock frequency.
*/
u_int64_t counterval[2];
/* Set RTC to binary mode. */
writertc(RTC_STATUSB, (rtcin(RTC_STATUSB) | RTCSB_BCD));
/* Busy-wait for falling edge of RTC update. */
while (((rtcin(RTC_STATUSA) & RTCSA_TUP) == 0))
;
while (((rtcin(RTC_STATUSA)& RTCSA_TUP) != 0))
;
counterval[0] = mips_rd_count();
/* Busy-wait for falling edge of RTC update. */
while (((rtcin(RTC_STATUSA) & RTCSA_TUP) == 0))
;
while (((rtcin(RTC_STATUSA)& RTCSA_TUP) != 0))
;
counterval[1] = mips_rd_count();
platform_counter_freq = counterval[1] - counterval[0];
#endif
if (platform_counter_freq == 0)
platform_counter_freq = MIPS_DEFAULT_HZ;
return (platform_counter_freq);
}
int
sysarch(struct thread *td, struct sysarch_args *uap)
{
int error;
void *tlsbase;
switch (uap->op) {
case MIPS_SET_TLS:
td->td_md.md_tls = uap->parms;
/*
* If there is an user local register implementation (ULRI)
* update it as well. Add the TLS and TCB offsets so the
* value in this register is adjusted like in the case of the
* rdhwr trap() instruction handler.
*
* XXXSS For more information why this offset is required see:
* 'git show c6be4f4d2d1b71c04de5d3bbb6933ce2dbcdb317'
*/
if (cpuinfo.userlocal_reg == true) {
#if defined(__mips_n64) && defined(COMPAT_FREEBSD32)
mips_wr_userlocal((unsigned long)(uap->parms +
TLS_TP_OFFSET + TLS_TCB_SIZE32));
#else
mips_wr_userlocal((unsigned long)(uap->parms +
TLS_TP_OFFSET + TLS_TCB_SIZE));
#endif
}
return (0);
case MIPS_GET_TLS:
tlsbase = td->td_md.md_tls;
error = copyout(&tlsbase, uap->parms, sizeof(tlsbase));
return (error);
case MIPS_GET_COUNT:
td->td_retval[0] = mips_rd_count();
return (0);
default:
break;
}
return (EINVAL);
}
static uint64_t
tick_ticker(void)
{
uint64_t ret;
uint32_t ticktock;
uint32_t t_lower_last, t_upper;
/*
* Disable preemption because we are working with cpu specific data.
*/
critical_enter();
/*
* Note that even though preemption is disabled, interrupts are
* still enabled. In particular there is a race with clock_intr()
* reading the values of 'counter_upper' and 'counter_lower_last'.
*
* XXX this depends on clock_intr() being executed periodically
* so that 'counter_upper' and 'counter_lower_last' are not stale.
*/
do {
t_upper = DPCPU_GET(counter_upper);
t_lower_last = DPCPU_GET(counter_lower_last);
} while (t_upper != DPCPU_GET(counter_upper));
ticktock = mips_rd_count();
critical_exit();
/* COUNT register wrapped around */
if (ticktock < t_lower_last)
t_upper++;
ret = ((uint64_t)t_upper << 32) | ticktock;
return (ret);
}
static unsigned
counter_get_timecount(struct timecounter *tc)
{
return (mips_rd_count());
}
void
platform_start(__register_t a0, __register_t a1, __register_t a2,
__register_t a3)
{
vm_offset_t kernend;
uint64_t platform_counter_freq;
int argc = a0;
char **argv = (char **)a1;
char **envp = (char **)a2;
unsigned int memsize = a3;
int i;
/* clear the BSS and SBSS segments */
kernend = round_page((vm_offset_t)&end);
memset(&edata, 0, kernend - (vm_offset_t)(&edata));
cninit();
printf("entry: platform_start()\n");
bootverbose = 1;
if (bootverbose) {
printf("cmd line: ");
for (i = 0; i < argc; i++)
printf("%s ", argv[i]);
printf("\n");
printf("envp:\n");
for (i = 0; envp[i]; i += 2)
printf("\t%s = %s\n", envp[i], envp[i+1]);
printf("memsize = %08x\n", memsize);
}
realmem = btoc(memsize);
mips_init();
do {
#if defined(TICK_USE_YAMON_FREQ)
/*
* If we are running on a board which uses YAMON firmware,
* then query CPU pipeline clock from the syscon object.
* If unsuccessful, use hard-coded default.
*/
platform_counter_freq = yamon_getcpufreq();
if (platform_counter_freq == 0)
platform_counter_freq = MIPS_DEFAULT_HZ;
#elif defined(TICK_USE_MALTA_RTC)
/*
* If we are running on a board with the MC146818 RTC,
* use it to determine CPU pipeline clock frequency.
*/
u_int64_t counterval[2];
/* Set RTC to binary mode. */
writertc(RTC_STATUSB, (rtcin(RTC_STATUSB) | RTCSB_BCD));
/* Busy-wait for falling edge of RTC update. */
while (((rtcin(RTC_STATUSA) & RTCSA_TUP) == 0))
;
while (((rtcin(RTC_STATUSA)& RTCSA_TUP) != 0))
;
counterval[0] = mips_rd_count();
/* Busy-wait for falling edge of RTC update. */
while (((rtcin(RTC_STATUSA) & RTCSA_TUP) == 0))
;
while (((rtcin(RTC_STATUSA)& RTCSA_TUP) != 0))
;
counterval[1] = mips_rd_count();
platform_counter_freq = counterval[1] - counterval[0];
#endif
} while(0);
mips_timer_init_params(platform_counter_freq, 0);
}