This patch switches macppc to clockintr(9).
It has survived two or three parallel release builds on my G4 MDD
(PowerMac7,3) and upgrades from the resulting bsd.rd. The machine
does not have a working IDE drive at the moment, so I booted and built
over USB 1.1 on an external drive.
It needs testing on a beefier Mac. It should probably also be tested
on a Mac with a working graphics card.
I am aware of gkoehler@'s work on suspend/resume. We'll need to
coordinate this to avoid breaking things.
Notes:
- There are no longer separate counters for "clock" and "stat".
Index: sys/arch/macppc/macppc/clock.c
===================================================================
RCS file: /cvs/src/sys/arch/macppc/macppc/clock.c,v
retrieving revision 1.50
diff -u -p -r1.50 clock.c
--- sys/arch/macppc/macppc/clock.c 8 Sep 2022 03:06:33 -0000 1.50
+++ sys/arch/macppc/macppc/clock.c 6 Nov 2022 19:15:15 -0000
@@ -35,7 +35,9 @@
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
+#include <sys/clockintr.h>
#include <sys/evcount.h>
+#include <sys/stdint.h>
#include <sys/timetc.h>
#include <machine/autoconf.h>
@@ -46,6 +48,8 @@
#include <dev/clock_subr.h>
#include <dev/ofw/openfirm.h>
+void dec_rearm(void *, uint64_t);
+void dec_trigger(void *);
void decr_intr(struct clockframe *frame);
u_int tb_get_timecount(struct timecounter *);
@@ -54,7 +58,14 @@ u_int tb_get_timecount(struct timecounte
*/
u_int32_t ticks_per_sec = 3125000;
u_int32_t ns_per_tick = 320;
-static int32_t ticks_per_intr;
+uint64_t dec_nsec_cycle_ratio;
+uint64_t dec_nsec_max;
+static int initialized;
+
+const struct intrclock dec_intrclock = {
+ .ic_rearm = dec_rearm,
+ .ic_trigger = dec_trigger
+};
static struct timecounter tb_timecounter = {
.tc_get_timecount = tb_get_timecount,
@@ -75,15 +86,8 @@ static const char *calibrate_tc_models[]
time_read_t *time_read;
time_write_t *time_write;
-/* vars for stats */
-int statint;
-u_int32_t statvar;
-u_int32_t statmin;
-
static struct evcount clk_count;
-static struct evcount stat_count;
static int clk_irq = PPC_CLK_IRQ;
-static int stat_irq = PPC_STAT_IRQ;
extern todr_chip_handle_t todr_handle;
struct todr_chip_handle rtc_todr;
@@ -115,18 +119,16 @@ rtc_settime(struct todr_chip_handle *han
void
decr_intr(struct clockframe *frame)
{
- u_int64_t tb;
- u_int64_t nextevent;
struct cpu_info *ci = curcpu();
- int nstats;
int s;
- /*
- * Check whether we are initialized.
- */
- if (!ticks_per_intr)
+ if (!initialized)
return;
+ clk_count.ec_count++; /* XXX not atomic */
+
+ ppc_mtdec(UINT32_MAX >> 1); /* clear DEC exception */
+
/*
* We can't actually mask DEC interrupts at or above IPL_CLOCK
* without masking other essential interrupts. To simulate
@@ -135,73 +137,15 @@ decr_intr(struct clockframe *frame)
*/
if (ci->ci_cpl >= IPL_CLOCK) {
ci->ci_dec_deferred = 1;
- ppc_mtdec(UINT32_MAX >> 1); /* clear DEC exception */
return;
}
ci->ci_dec_deferred = 0;
- /*
- * Based on the actual time delay since the last decrementer reload,
- * we arrange for earlier interrupt next time.
- */
-
- tb = ppc_mftb();
- while (ci->ci_nexttimerevent <= tb)
- ci->ci_nexttimerevent += ticks_per_intr;
-
- ci->ci_prevtb = ci->ci_nexttimerevent - ticks_per_intr;
-
- for (nstats = 0; ci->ci_nextstatevent <= tb; nstats++) {
- int r;
- do {
- r = random() & (statvar -1);
- } while (r == 0); /* random == 0 not allowed */
- ci->ci_nextstatevent += statmin + r;
- }
-
- /* only count timer ticks for CLK_IRQ */
- stat_count.ec_count += nstats;
-
- if (ci->ci_nexttimerevent < ci->ci_nextstatevent)
- nextevent = ci->ci_nexttimerevent;
- else
- nextevent = ci->ci_nextstatevent;
-
- /*
- * Need to work about the near constant skew this introduces???
- * reloading tb here could cause a missed tick.
- */
- ppc_mtdec(nextevent - tb);
-
- nstats += ci->ci_statspending;
- ci->ci_statspending = 0;
-
s = splclock();
-
- /*
- * Reenable interrupts
- */
ppc_intr_enable(1);
-
- /*
- * Do standard timer interrupt stuff.
- */
- while (ci->ci_lasttb < ci->ci_prevtb) {
- /* sync lasttb with hardclock */
- ci->ci_lasttb += ticks_per_intr;
- clk_count.ec_count++;
- hardclock(frame);
- }
-
- while (nstats-- > 0)
- statclock(frame);
-
+ clockintr_dispatch(frame);
splx(s);
(void) ppc_intr_disable();
-
- /* if a tick has occurred while dealing with these,
- * dont service it now, delay until the next tick.
- */
}
void cpu_startclock(void);
@@ -210,7 +154,6 @@ void
cpu_initclocks(void)
{
int intrstate;
- int minint;
u_int32_t first_tb, second_tb;
time_t first_sec, sec;
int calibrate = 0, n;
@@ -242,6 +185,7 @@ cpu_initclocks(void)
ticks_per_sec);
#endif
}
+ ns_per_tick = 1000000000 / ticks_per_sec;
tb_timecounter.tc_frequency = ticks_per_sec;
tc_init(&tb_timecounter);
@@ -252,23 +196,16 @@ cpu_initclocks(void)
intrstate = ppc_intr_disable();
- ticks_per_intr = ticks_per_sec / hz;
-
stathz = 100;
profhz = 1000; /* must be a multiple of stathz */
+ clockintr_init(CL_RNDSTAT);
- /* init secondary clock to stathz */
- statint = ticks_per_sec / stathz;
- statvar = 0x40000000; /* really big power of two */
- /* find largest 2^n which is nearly smaller than statint/2 */
- minint = statint / 2 + 100;
- while (statvar > minint)
- statvar >>= 1;
- statmin = statint - (statvar >> 1);
+ dec_nsec_cycle_ratio = ticks_per_sec * (1ULL << 32) / 1000000000;
+ dec_nsec_max = UINT64_MAX / dec_nsec_cycle_ratio;
evcount_attach(&clk_count, "clock", &clk_irq);
- evcount_attach(&stat_count, "stat", &stat_irq);
+ initialized = 1;
cpu_startclock();
ppc_intr_enable(intrstate);
@@ -277,21 +214,8 @@ cpu_initclocks(void)
void
cpu_startclock(void)
{
- struct cpu_info *ci = curcpu();
- u_int64_t nextevent;
-
- ci->ci_lasttb = ppc_mftb();
-
- /*
- * no point in having random on the first tick,
- * it just complicates the code.
- */
- ci->ci_nexttimerevent = ci->ci_lasttb + ticks_per_intr;
- nextevent = ci->ci_nextstatevent = ci->ci_nexttimerevent;
-
- ci->ci_statspending = 0;
-
- ppc_mtdec(nextevent - ci->ci_lasttb);
+ clockintr_cpu_init(&dec_intrclock);
+ clockintr_trigger();
}
/*
@@ -308,35 +232,41 @@ delay(unsigned n)
;
}
-/*
- * Nothing to do.
- */
void
setstatclockrate(int newhz)
{
- int minint;
- int intrstate;
-
- intrstate = ppc_intr_disable();
-
- statint = ticks_per_sec / newhz;
- statvar = 0x40000000; /* really big power of two */
- /* find largest 2^n which is nearly smaller than statint/2 */
- minint = statint / 2 + 100;
- while (statvar > minint)
- statvar >>= 1;
-
- statmin = statint - (statvar >> 1);
- ppc_intr_enable(intrstate);
-
- /*
- * XXX this allows the next stat timer to occur then it switches
- * to the new frequency. Rather than switching instantly.
- */
+ clockintr_setstatclockrate(newhz);
}
u_int
tb_get_timecount(struct timecounter *tc)
{
return ppc_mftbl();
+}
+
+void
+dec_rearm(void *unused, uint64_t nsecs)
+{
+ uint32_t cycles;
+ int s;
+
+ if (nsecs > dec_nsec_max)
+ nsecs = dec_nsec_max;
+ cycles = (nsecs * dec_nsec_cycle_ratio) >> 32;
+ if (cycles > UINT32_MAX >> 1)
+ cycles = UINT32_MAX >> 1;
+ s = ppc_intr_disable();
+ ppc_mtdec(cycles);
+ ppc_intr_enable(s);
+}
+
+void
+dec_trigger(void *unused)
+{
+ int s;
+
+ s = ppc_intr_disable();
+ ppc_mtdec(0);
+ ppc_mtdec(UINT32_MAX);
+ ppc_intr_enable(s);
}
Index: sys/arch/powerpc/include/cpu.h
===================================================================
RCS file: /cvs/src/sys/arch/powerpc/include/cpu.h,v
retrieving revision 1.73
diff -u -p -r1.73 cpu.h
--- sys/arch/powerpc/include/cpu.h 21 Oct 2022 21:26:49 -0000 1.73
+++ sys/arch/powerpc/include/cpu.h 6 Nov 2022 19:15:15 -0000
@@ -36,6 +36,7 @@
#include <machine/frame.h>
+#include <sys/clockintr.h>
#include <sys/device.h>
#include <sys/sched.h>
#include <sys/srp.h>
@@ -72,11 +73,7 @@ struct cpu_info {
#define DISISAVE_LEN 4
register_t ci_disisave[DISISAVE_LEN];
- volatile u_int64_t ci_nexttimerevent;
- volatile u_int64_t ci_prevtb;
- volatile u_int64_t ci_lasttb;
- volatile u_int64_t ci_nextstatevent;
- int ci_statspending;
+ struct clockintr_queue ci_queue;
volatile int ci_ddb_paused;
#define CI_DDB_RUNNING 0
Index: sys/arch/powerpc/include/_types.h
===================================================================
RCS file: /cvs/src/sys/arch/powerpc/include/_types.h,v
retrieving revision 1.23
diff -u -p -r1.23 _types.h
--- sys/arch/powerpc/include/_types.h 5 Mar 2018 01:15:25 -0000 1.23
+++ sys/arch/powerpc/include/_types.h 6 Nov 2022 19:15:15 -0000
@@ -35,6 +35,8 @@
#ifndef _POWERPC__TYPES_H_
#define _POWERPC__TYPES_H_
+#define __HAVE_CLOCKINTR
+
#if defined(_KERNEL)
typedef struct label_t {
long val[25];
