Aren
/
NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Add a new function, hp300_calibrate_delay(), which sets the delay constant 

based on a model's known CPU speed.  cpuspeed value is now in MHz
instead of (MHz / 8).
This commit is contained in:
thorpej 1996-05-17 15:32:26 +00:00
parent 33e1caaf99
commit d845719070
1 changed files with 57 additions and 33 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

90
sys/arch/hp300/hp300/machdep.c
View File

@ -1,4 +1,4 @@
/* $NetBSD: machdep.c,v 1.63 1996/04/27 00:39:59 thorpej Exp $ */
/* $NetBSD: machdep.c,v 1.64 1996/05/17 15:32:26 thorpej Exp $ */
/*
* Copyright (c) 1988 University of Utah.
@ -133,6 +133,61 @@ caddr_t conaddr; /* for drivers in cn_init() */
int convasize; /* size of mapped console device */
int conforced; /* console has been forced */
/*
* Note that the value of delay_divisor is roughly
* 2048 / cpuspeed (where cpuspeed is in MHz).
*
* XXX At the moment, delay_divisor is based on cpuspeed,
* XXX which is set according to CPU model. Eventually,
* XXX we should calibrate delay_divisor, and calculate
* XXX the actual CPU speed.
*/
int cpuspeed = 0; /* relative cpu speed -- can be patched */
int delay_divisor = 40; /* default to 50MHz CPU */
void hp300_calibrate_delay __P((void));
/*
* Calibrate delay_divisor. Right now, this is just based on CPU
* speeds of known models.
*/
void
hp300_calibrate_delay()
{
/*
* XXX The 16MHz CPUs are actually 16.67 ... should we round
* XXX these up to 17?
*/
if (cpuspeed == 0) {
switch (machineid) {
case HP_320:
case HP_330:
case HP_340:
cpuspeed = 16;
break;
case HP_350:
case HP_360:
case HP_380:
cpuspeed = 25;
break;
case HP_370:
case HP_433:
cpuspeed = 33;
break;
case HP_375:
cpuspeed = 50;
break;
default: /* assume the fastest */
cpuspeed = 50;
break;
}
}
delay_divisor = 2048 / cpuspeed;
}
/*
* Console initialization: called early on from main,
* before vm init or startup. Do enough configuration
@ -151,38 +206,6 @@ consinit()
conforced = 0;
conscode = 1024; /* invalid */
/*
* Set cpuspeed immediately since hp300_cninit() called routines
* might use delay. Note that we only set it if a custom value
* has not already been specified.
*/
if (cpuspeed == 0) {
switch (machineid) {
case HP_320:
case HP_330:
case HP_340:
cpuspeed = MHZ_16;
break;
case HP_350:
case HP_360:
case HP_380:
cpuspeed = MHZ_25;
break;
case HP_370:
case HP_433:
cpuspeed = MHZ_33;
break;
case HP_375:
cpuspeed = MHZ_50;
break;
default: /* assume the fastest */
cpuspeed = MHZ_50;
break;
}
if (mmutype == MMU_68040)
cpuspeed *= 2; /* XXX */
}
/*
* Initialize the DIO resource map.
*/
@ -594,6 +617,7 @@ identifycpu()
}
strcat(cpu_model, ")");
printf("%s\n", cpu_model);
printf("delay constant for %dMHz cpu: %d\n", cpuspeed, delay_divisor);
/*
* Now that we have told the user what they have,
* let them know if that machine type isn't configured.