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Diffstat (limited to 'arch/mips/kernel/csrc-powertv.c')
-rw-r--r--arch/mips/kernel/csrc-powertv.c35
1 files changed, 3 insertions, 32 deletions
diff --git a/arch/mips/kernel/csrc-powertv.c b/arch/mips/kernel/csrc-powertv.c
index a27c16c8690e..2e7c5232da8d 100644
--- a/arch/mips/kernel/csrc-powertv.c
+++ b/arch/mips/kernel/csrc-powertv.c
@@ -78,9 +78,7 @@ static void __init powertv_c0_hpt_clocksource_init(void)
clocksource_mips.rating = 200 + mips_hpt_frequency / 10000000;
- clocksource_set_clock(&clocksource_mips, mips_hpt_frequency);
-
- clocksource_register(&clocksource_mips);
+ clocksource_register_hz(&clocksource_mips, mips_hpt_frequency);
}
/**
@@ -130,43 +128,16 @@ static struct clocksource clocksource_tim_c = {
/**
* powertv_tim_c_clocksource_init - set up a clock source for the TIM_C clock
*
- * The hard part here is coming up with a constant k and shift s such that
- * the 48-bit TIM_C value multiplied by k doesn't overflow and that value,
- * when shifted right by s, yields the corresponding number of nanoseconds.
* We know that TIM_C counts at 27 MHz/8, so each cycle corresponds to
- * 1 / (27,000,000/8) seconds. Multiply that by a billion and you get the
- * number of nanoseconds. Since the TIM_C value has 48 bits and the math is
- * done in 64 bits, avoiding an overflow means that k must be less than
- * 64 - 48 = 16 bits.
+ * 1 / (27,000,000/8) seconds.
*/
static void __init powertv_tim_c_clocksource_init(void)
{
- int prescale;
- unsigned long dividend;
- unsigned long k;
- int s;
- const int max_k_bits = (64 - 48) - 1;
- const unsigned long billion = 1000000000;
const unsigned long counts_per_second = 27000000 / 8;
- prescale = BITS_PER_LONG - ilog2(billion) - 1;
- dividend = billion << prescale;
- k = dividend / counts_per_second;
- s = ilog2(k) - max_k_bits;
-
- if (s < 0)
- s = prescale;
-
- else {
- k >>= s;
- s += prescale;
- }
-
- clocksource_tim_c.mult = k;
- clocksource_tim_c.shift = s;
clocksource_tim_c.rating = 200;
- clocksource_register(&clocksource_tim_c);
+ clocksource_register_hz(&clocksource_tim_c, counts_per_second);
tim_c = (struct tim_c *) asic_reg_addr(tim_ch);
}