Only use the i8254 delay code if we are specifically using the i8254 as

delay func.  Otherwise simply delay for a second to calibrate the LAPIC.
Install the lapic delay func only if we were using the i8254 before as
delay func.

Discussed with the hackroom
ok kettenis@

diff --git a/sys/arch/amd64/amd64/lapic.c b/sys/arch/amd64/amd64/lapic.c
index 7232d62..a94689b 100644 (file)
--- a/sys/arch/amd64/amd64/lapic.c
+++ b/sys/arch/amd64/amd64/lapic.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: lapic.c,v 1.58 2021/06/11 05:33:16 jsg Exp $  */
+/*     $OpenBSD: lapic.c,v 1.59 2021/08/31 15:53:36 patrick Exp $      */
 /* $NetBSD: lapic.c,v 1.2 2003/05/08 01:04:35 fvdl Exp $ */
 
 /*-
@@ -521,31 +521,40 @@ lapic_calibrate_timer(struct cpu_info *ci)
         */
        lapic_timer_oneshot(LAPIC_LVTT_M, 0x80000000);
 
-       s = intr_disable();
+       if (delay_func == i8254_delay) {
+               s = intr_disable();
 
-       /* wait for current cycle to finish */
-       wait_next_cycle();
+               /* wait for current cycle to finish */
+               wait_next_cycle();
 
-       startapic = lapic_gettick();
+               startapic = lapic_gettick();
 
-       /* wait the next hz cycles */
-       for (i = 0; i < hz; i++)
-               wait_next_cycle();
+               /* wait the next hz cycles */
+               for (i = 0; i < hz; i++)
+                       wait_next_cycle();
 
-       endapic = lapic_gettick();
+               endapic = lapic_gettick();
 
-       intr_restore(s);
+               intr_restore(s);
 
-       dtick = hz * rtclock_tval;
-       dapic = startapic-endapic;
+               dtick = hz * rtclock_tval;
+               dapic = startapic-endapic;
 
-       /*
-        * there are TIMER_FREQ ticks per second.
-        * in dtick ticks, there are dapic bus clocks.
-        */
-       tmp = (TIMER_FREQ * dapic) / dtick;
+               /*
+                * there are TIMER_FREQ ticks per second.
+                * in dtick ticks, there are dapic bus clocks.
+                */
+               tmp = (TIMER_FREQ * dapic) / dtick;
 
-       lapic_per_second = tmp;
+               lapic_per_second = tmp;
+       } else {
+               s = intr_disable();
+               startapic = lapic_gettick();
+               delay(1 * 1000 * 1000);
+               endapic = lapic_gettick();
+               intr_restore(s);
+               lapic_per_second = startapic - endapic;
+       }
 
 skip_calibration:
        printf("%s: apic clock running at %dMHz\n",
@@ -585,7 +594,7 @@ skip_calibration:
                 * Now that the timer's calibrated, use the apic timer routines
                 * for all our timing needs..
                 */
-               if (delay_func != tsc_delay)
+               if (delay_func == i8254_delay)
                        delay_func = lapic_delay;
                initclock_func = lapic_initclocks;
        }
@@ -658,7 +667,7 @@ i82489_ipi_init(int target)
 
        i82489_icr_wait();
 
-       i8254_delay(10000);
+       delay(10000);
 
        i82489_writereg(LAPIC_ICRLO, (target & LAPIC_DEST_MASK) |
             LAPIC_DLMODE_INIT | LAPIC_LVL_TRIG | LAPIC_LVL_DEASSERT);
@@ -697,7 +706,7 @@ x2apic_ipi_init(int target)
        x2apic_writeicr(hi, (target & LAPIC_DEST_MASK) | LAPIC_DLMODE_INIT |
            LAPIC_LVL_ASSERT );
 
-       i8254_delay(10000);
+       delay(10000);
 
        x2apic_writeicr(0, (target & LAPIC_DEST_MASK) | LAPIC_DLMODE_INIT |
            LAPIC_LVL_TRIG | LAPIC_LVL_DEASSERT);