diff options
| -rw-r--r-- | chip/mt_scp/clock.c | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/chip/mt_scp/clock.c b/chip/mt_scp/clock.c index 14ea5ea67a..311346eb8f 100644 --- a/chip/mt_scp/clock.c +++ b/chip/mt_scp/clock.c @@ -96,6 +96,19 @@ static void scp_ulposc_config(int osc) AP_ULPOSC_CON13(osc) |= OSC_DIV2_EN; } +static inline void busy_udelay(int usec) +{ + /* + * Delaying by busy-looping, for place that can't use udelay because of + * the clock not configured yet. The value 28 is chosen approximately + * from experiment. + */ + volatile int i = usec * 28; + + while (i--) + ; +} + void scp_clock_high_enable(int osc) { /* Enable high speed clock */ @@ -104,14 +117,14 @@ void scp_clock_high_enable(int osc) switch (osc) { case 0: /* After 25ms, enable ULPOSC */ - udelay(25 * MSEC); + busy_udelay(25 * MSEC); SCP_CLK_EN |= CG_CLK_HIGH; break; case 1: /* Turn off ULPOSC2 high-core-disable switch */ SCP_CLK_ON_CTRL &= ~HIGH_CORE_DIS_SUB; /* After 25ms, turn on ULPOSC2 high core clock gate */ - udelay(25 * MSEC); + busy_udelay(25 * MSEC); SCP_CLK_HIGH_CORE |= CLK_HIGH_CORE_CG; break; default: |