jhb ad1ee10f6d Use the local APIC timer to drive the various kernel clocks on SMP machines ... rather than forwarding interrupts from the clock devices around using IPIs: - Add an IDT vector that pushes a clock frame and calls lapic_handle_timer(). - Add functions to program the local APIC timer including setting the divisor, and setting up the timer to either down a periodic countdown or one-shot countdown. - Add a lapic_setup_clock() function that the BSP calls from cpu_init_clocks() to setup the local APIC timer if it is going to be used. The setup uses a one-shot countdown to calibrate the timer. We then program the timer on each CPU to fire at a frequency of hz * 3. stathz is defined as freq / 23 (hz * 3 / 23), and profhz is defined as freq / 2 (hz * 3 / 2). This gives the clocks relatively prime divisors while keeping a low LCM for the frequency of the clock interrupts. Thanks to Peter Jeremy for suggesting this approach. - Remove the hardclock and statclock forwarding code including the two associated IPIs. The bitmap IPI handler has now effectively degenerated to just IPI_AST. - When the local APIC timer is used we don't turn the RTC on at all, but we still enable interrupts on the ISA timer 0 (i8254) for timecounting purposes.		2005-02-08 20:25:07 +00:00
..
atkbd_isa.c
atkbdc_isa.c
atrtc.c	Use the local APIC timer to drive the various kernel clocks on SMP machines	2005-02-08 20:25:07 +00:00
isa_common.c
isa_common.h
isa_if.m
isahint.c
isareg.h
isavar.h	Since we are quite unlikely to ever face another platform which	2005-02-06 13:46:39 +00:00
orm.c
pnp.c
pnpparse.c
pnpreg.h
pnpvar.h
psm.c
rtc.h
syscons_isa.c
vga_isa.c