static int cpg_mstp_clock_endisable(struct clk_hw *hw, bool enable)
{
struct mstp_clock *clock = to_mstp_clock(hw);
struct mstp_clock_group *group = clock->group;
u32 bitmask = BIT(clock->bit_index);
unsigned long flags;
unsigned int i;
u32 value;
spin_lock_irqsave(&group->lock, flags);
value = cpg_mstp_read(group, group->smstpcr);
if (enable)
value &= ~bitmask;
else
value |= bitmask;
cpg_mstp_write(group, value, group->smstpcr);
if (!group->mstpsr) {
/* dummy read to ensure write has completed */
cpg_mstp_read(group, group->smstpcr);
barrier_data(group->smstpcr);
}
spin_unlock_irqrestore(&group->lock, flags);
if (!enable || !group->mstpsr)
return 0;
for (i = 1000; i > 0; --i) {
if (!(cpg_mstp_read(group, group->mstpsr) & bitmask))
break;
cpu_relax();
}
if (!i) {
pr_err("%s: failed to enable %p[%d]\n", __func__,
group->smstpcr, clock->bit_index);
return -ETIMEDOUT;
}
return 0;
}
/**
* memzero_explicit - Fill a region of memory (e.g. sensitive
* keying data) with 0s.
* @s: Pointer to the start of the area.
* @count: The size of the area.
*
* Note: usually using memset() is just fine (!), but in cases
* where clearing out _local_ data at the end of a scope is
* necessary, memzero_explicit() should be used instead in
* order to prevent the compiler from optimising away zeroing.
*
* memzero_explicit() doesn't need an arch-specific version as
* it just invokes the one of memset() implicitly.
*/
void memzero_explicit(void *s, size_t count)
{
memset(s, 0, count);
barrier_data(s);
}