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rtl8139: remove muldiv64()
Originally, timers were ticks based, and it made sense to
add ticks to current time to know when to trigger an alarm.
But since commit:
7447545
change all other clock references to use nanosecond resolution accessors
All timers use nanoseconds and we need to convert ticks to nanoseconds, by
doing something like:
y = muldiv64(x, get_ticks_per_sec(), PCI_FREQUENCY)
where x is the number of device ticks and y the number of system ticks.
y is used as nanoseconds in timer functions,
it works because 1 tick is 1 nanosecond.
(get_ticks_per_sec() is 10^9)
But as PCI frequency is 33 MHz, we can also do:
y = x * 30; /* 33 MHz PCI period is 30 ns */
Which is much more simple.
This implies a 33.333333 MHz PCI frequency,
but this is correct.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
parent
9491e9bc01
commit
37b9ab92f7
2 changed files with 7 additions and 9 deletions
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@ -20,7 +20,7 @@ static void nop(void)
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{
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}
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#define CLK 33000000
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#define CLK 33333333
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static QPCIBus *pcibus;
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static QPCIDevice *dev;
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