mirror of
https://github.com/torvalds/linux.git
synced 2024-11-22 12:11:40 +00:00
c98aa86df3
The USEC_TO_HZ and HZ_TO_USEC constant sets were mislabelled, with seriously incorrect results. This among other things manifested itself as cpufreq not working when a tickless kernel was configured. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Tested-by: Carlos R. Mafra <crmafra@ift.unesp.br> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
403 lines
9.4 KiB
Perl
403 lines
9.4 KiB
Perl
#!/usr/bin/perl
|
|
# -----------------------------------------------------------------------
|
|
#
|
|
# Copyright 2007 rPath, Inc. - All Rights Reserved
|
|
#
|
|
# This file is part of the Linux kernel, and is made available under
|
|
# the terms of the GNU General Public License version 2 or (at your
|
|
# option) any later version; incorporated herein by reference.
|
|
#
|
|
# -----------------------------------------------------------------------
|
|
#
|
|
|
|
#
|
|
# Usage: timeconst.pl HZ > timeconst.h
|
|
#
|
|
|
|
# Precomputed values for systems without Math::BigInt
|
|
# Generated by:
|
|
# timeconst.pl --can 24 32 48 64 100 122 128 200 250 256 300 512 1000 1024 1200
|
|
%canned_values = (
|
|
24 => [
|
|
'0xa6aaaaab','0x2aaaaaa',26,
|
|
'0xa6aaaaaaaaaaaaab','0x2aaaaaaaaaaaaaa',58,
|
|
125,3,
|
|
'0xc49ba5e4','0x1fbe76c8b4',37,
|
|
'0xc49ba5e353f7ceda','0x1fbe76c8b439581062',69,
|
|
3,125,
|
|
'0xa2c2aaab','0xaaaa',16,
|
|
'0xa2c2aaaaaaaaaaab','0xaaaaaaaaaaaa',48,
|
|
125000,3,
|
|
'0xc9539b89','0x7fffbce4217d',47,
|
|
'0xc9539b8887229e91','0x7fffbce4217d2849cb25',79,
|
|
3,125000,
|
|
], 32 => [
|
|
'0xfa000000','0x6000000',27,
|
|
'0xfa00000000000000','0x600000000000000',59,
|
|
125,4,
|
|
'0x83126e98','0xfdf3b645a',36,
|
|
'0x83126e978d4fdf3c','0xfdf3b645a1cac0831',68,
|
|
4,125,
|
|
'0xf4240000','0x0',17,
|
|
'0xf424000000000000','0x0',49,
|
|
31250,1,
|
|
'0x8637bd06','0x3fff79c842fa',46,
|
|
'0x8637bd05af6c69b6','0x3fff79c842fa5093964a',78,
|
|
1,31250,
|
|
], 48 => [
|
|
'0xa6aaaaab','0x6aaaaaa',27,
|
|
'0xa6aaaaaaaaaaaaab','0x6aaaaaaaaaaaaaa',59,
|
|
125,6,
|
|
'0xc49ba5e4','0xfdf3b645a',36,
|
|
'0xc49ba5e353f7ceda','0xfdf3b645a1cac0831',68,
|
|
6,125,
|
|
'0xa2c2aaab','0x15555',17,
|
|
'0xa2c2aaaaaaaaaaab','0x1555555555555',49,
|
|
62500,3,
|
|
'0xc9539b89','0x3fffbce4217d',46,
|
|
'0xc9539b8887229e91','0x3fffbce4217d2849cb25',78,
|
|
3,62500,
|
|
], 64 => [
|
|
'0xfa000000','0xe000000',28,
|
|
'0xfa00000000000000','0xe00000000000000',60,
|
|
125,8,
|
|
'0x83126e98','0x7ef9db22d',35,
|
|
'0x83126e978d4fdf3c','0x7ef9db22d0e560418',67,
|
|
8,125,
|
|
'0xf4240000','0x0',18,
|
|
'0xf424000000000000','0x0',50,
|
|
15625,1,
|
|
'0x8637bd06','0x1fff79c842fa',45,
|
|
'0x8637bd05af6c69b6','0x1fff79c842fa5093964a',77,
|
|
1,15625,
|
|
], 100 => [
|
|
'0xa0000000','0x0',28,
|
|
'0xa000000000000000','0x0',60,
|
|
10,1,
|
|
'0xcccccccd','0x733333333',35,
|
|
'0xcccccccccccccccd','0x73333333333333333',67,
|
|
1,10,
|
|
'0x9c400000','0x0',18,
|
|
'0x9c40000000000000','0x0',50,
|
|
10000,1,
|
|
'0xd1b71759','0x1fff2e48e8a7',45,
|
|
'0xd1b71758e219652c','0x1fff2e48e8a71de69ad4',77,
|
|
1,10000,
|
|
], 122 => [
|
|
'0x8325c53f','0xfbcda3a',28,
|
|
'0x8325c53ef368eb05','0xfbcda3ac10c9714',60,
|
|
500,61,
|
|
'0xf9db22d1','0x7fbe76c8b',35,
|
|
'0xf9db22d0e560418a','0x7fbe76c8b43958106',67,
|
|
61,500,
|
|
'0x8012e2a0','0x3ef36',18,
|
|
'0x8012e29f79b47583','0x3ef368eb04325',50,
|
|
500000,61,
|
|
'0xffda4053','0x1ffffbce4217',45,
|
|
'0xffda4052d666a983','0x1ffffbce4217d2849cb2',77,
|
|
61,500000,
|
|
], 128 => [
|
|
'0xfa000000','0x1e000000',29,
|
|
'0xfa00000000000000','0x1e00000000000000',61,
|
|
125,16,
|
|
'0x83126e98','0x3f7ced916',34,
|
|
'0x83126e978d4fdf3c','0x3f7ced916872b020c',66,
|
|
16,125,
|
|
'0xf4240000','0x40000',19,
|
|
'0xf424000000000000','0x4000000000000',51,
|
|
15625,2,
|
|
'0x8637bd06','0xfffbce4217d',44,
|
|
'0x8637bd05af6c69b6','0xfffbce4217d2849cb25',76,
|
|
2,15625,
|
|
], 200 => [
|
|
'0xa0000000','0x0',29,
|
|
'0xa000000000000000','0x0',61,
|
|
5,1,
|
|
'0xcccccccd','0x333333333',34,
|
|
'0xcccccccccccccccd','0x33333333333333333',66,
|
|
1,5,
|
|
'0x9c400000','0x0',19,
|
|
'0x9c40000000000000','0x0',51,
|
|
5000,1,
|
|
'0xd1b71759','0xfff2e48e8a7',44,
|
|
'0xd1b71758e219652c','0xfff2e48e8a71de69ad4',76,
|
|
1,5000,
|
|
], 250 => [
|
|
'0x80000000','0x0',29,
|
|
'0x8000000000000000','0x0',61,
|
|
4,1,
|
|
'0x80000000','0x180000000',33,
|
|
'0x8000000000000000','0x18000000000000000',65,
|
|
1,4,
|
|
'0xfa000000','0x0',20,
|
|
'0xfa00000000000000','0x0',52,
|
|
4000,1,
|
|
'0x83126e98','0x7ff7ced9168',43,
|
|
'0x83126e978d4fdf3c','0x7ff7ced916872b020c4',75,
|
|
1,4000,
|
|
], 256 => [
|
|
'0xfa000000','0x3e000000',30,
|
|
'0xfa00000000000000','0x3e00000000000000',62,
|
|
125,32,
|
|
'0x83126e98','0x1fbe76c8b',33,
|
|
'0x83126e978d4fdf3c','0x1fbe76c8b43958106',65,
|
|
32,125,
|
|
'0xf4240000','0xc0000',20,
|
|
'0xf424000000000000','0xc000000000000',52,
|
|
15625,4,
|
|
'0x8637bd06','0x7ffde7210be',43,
|
|
'0x8637bd05af6c69b6','0x7ffde7210be9424e592',75,
|
|
4,15625,
|
|
], 300 => [
|
|
'0xd5555556','0x2aaaaaaa',30,
|
|
'0xd555555555555556','0x2aaaaaaaaaaaaaaa',62,
|
|
10,3,
|
|
'0x9999999a','0x1cccccccc',33,
|
|
'0x999999999999999a','0x1cccccccccccccccc',65,
|
|
3,10,
|
|
'0xd0555556','0xaaaaa',20,
|
|
'0xd055555555555556','0xaaaaaaaaaaaaa',52,
|
|
10000,3,
|
|
'0x9d495183','0x7ffcb923a29',43,
|
|
'0x9d495182a9930be1','0x7ffcb923a29c779a6b5',75,
|
|
3,10000,
|
|
], 512 => [
|
|
'0xfa000000','0x7e000000',31,
|
|
'0xfa00000000000000','0x7e00000000000000',63,
|
|
125,64,
|
|
'0x83126e98','0xfdf3b645',32,
|
|
'0x83126e978d4fdf3c','0xfdf3b645a1cac083',64,
|
|
64,125,
|
|
'0xf4240000','0x1c0000',21,
|
|
'0xf424000000000000','0x1c000000000000',53,
|
|
15625,8,
|
|
'0x8637bd06','0x3ffef39085f',42,
|
|
'0x8637bd05af6c69b6','0x3ffef39085f4a1272c9',74,
|
|
8,15625,
|
|
], 1000 => [
|
|
'0x80000000','0x0',31,
|
|
'0x8000000000000000','0x0',63,
|
|
1,1,
|
|
'0x80000000','0x0',31,
|
|
'0x8000000000000000','0x0',63,
|
|
1,1,
|
|
'0xfa000000','0x0',22,
|
|
'0xfa00000000000000','0x0',54,
|
|
1000,1,
|
|
'0x83126e98','0x1ff7ced9168',41,
|
|
'0x83126e978d4fdf3c','0x1ff7ced916872b020c4',73,
|
|
1,1000,
|
|
], 1024 => [
|
|
'0xfa000000','0xfe000000',32,
|
|
'0xfa00000000000000','0xfe00000000000000',64,
|
|
125,128,
|
|
'0x83126e98','0x7ef9db22',31,
|
|
'0x83126e978d4fdf3c','0x7ef9db22d0e56041',63,
|
|
128,125,
|
|
'0xf4240000','0x3c0000',22,
|
|
'0xf424000000000000','0x3c000000000000',54,
|
|
15625,16,
|
|
'0x8637bd06','0x1fff79c842f',41,
|
|
'0x8637bd05af6c69b6','0x1fff79c842fa5093964',73,
|
|
16,15625,
|
|
], 1200 => [
|
|
'0xd5555556','0xd5555555',32,
|
|
'0xd555555555555556','0xd555555555555555',64,
|
|
5,6,
|
|
'0x9999999a','0x66666666',31,
|
|
'0x999999999999999a','0x6666666666666666',63,
|
|
6,5,
|
|
'0xd0555556','0x2aaaaa',22,
|
|
'0xd055555555555556','0x2aaaaaaaaaaaaa',54,
|
|
2500,3,
|
|
'0x9d495183','0x1ffcb923a29',41,
|
|
'0x9d495182a9930be1','0x1ffcb923a29c779a6b5',73,
|
|
3,2500,
|
|
]
|
|
);
|
|
|
|
$has_bigint = eval 'use Math::BigInt qw(bgcd); 1;';
|
|
|
|
sub bint($)
|
|
{
|
|
my($x) = @_;
|
|
return Math::BigInt->new($x);
|
|
}
|
|
|
|
#
|
|
# Constants for division by reciprocal multiplication.
|
|
# (bits, numerator, denominator)
|
|
#
|
|
sub fmul($$$)
|
|
{
|
|
my ($b,$n,$d) = @_;
|
|
|
|
$n = bint($n);
|
|
$d = bint($d);
|
|
|
|
return scalar (($n << $b)+$d-bint(1))/$d;
|
|
}
|
|
|
|
sub fadj($$$)
|
|
{
|
|
my($b,$n,$d) = @_;
|
|
|
|
$n = bint($n);
|
|
$d = bint($d);
|
|
|
|
$d = $d/bgcd($n, $d);
|
|
return scalar (($d-bint(1)) << $b)/$d;
|
|
}
|
|
|
|
sub fmuls($$$) {
|
|
my($b,$n,$d) = @_;
|
|
my($s,$m);
|
|
my($thres) = bint(1) << ($b-1);
|
|
|
|
$n = bint($n);
|
|
$d = bint($d);
|
|
|
|
for ($s = 0; 1; $s++) {
|
|
$m = fmul($s,$n,$d);
|
|
return $s if ($m >= $thres);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
# Provides mul, adj, and shr factors for a specific
|
|
# (bit, time, hz) combination
|
|
sub muladj($$$) {
|
|
my($b, $t, $hz) = @_;
|
|
my $s = fmuls($b, $t, $hz);
|
|
my $m = fmul($s, $t, $hz);
|
|
my $a = fadj($s, $t, $hz);
|
|
return ($m->as_hex(), $a->as_hex(), $s);
|
|
}
|
|
|
|
# Provides numerator, denominator values
|
|
sub numden($$) {
|
|
my($n, $d) = @_;
|
|
my $g = bgcd($n, $d);
|
|
return ($n/$g, $d/$g);
|
|
}
|
|
|
|
# All values for a specific (time, hz) combo
|
|
sub conversions($$) {
|
|
my ($t, $hz) = @_;
|
|
my @val = ();
|
|
|
|
# HZ_TO_xx
|
|
push(@val, muladj(32, $t, $hz));
|
|
push(@val, muladj(64, $t, $hz));
|
|
push(@val, numden($t, $hz));
|
|
|
|
# xx_TO_HZ
|
|
push(@val, muladj(32, $hz, $t));
|
|
push(@val, muladj(64, $hz, $t));
|
|
push(@val, numden($hz, $t));
|
|
|
|
return @val;
|
|
}
|
|
|
|
sub compute_values($) {
|
|
my($hz) = @_;
|
|
my @val = ();
|
|
my $s, $m, $a, $g;
|
|
|
|
if (!$has_bigint) {
|
|
die "$0: HZ == $hz not canned and ".
|
|
"Math::BigInt not available\n";
|
|
}
|
|
|
|
# MSEC conversions
|
|
push(@val, conversions(1000, $hz));
|
|
|
|
# USEC conversions
|
|
push(@val, conversions(1000000, $hz));
|
|
|
|
return @val;
|
|
}
|
|
|
|
sub output($@)
|
|
{
|
|
my($hz, @val) = @_;
|
|
my $pfx, $bit, $suf, $s, $m, $a;
|
|
|
|
print "/* Automatically generated by kernel/timeconst.pl */\n";
|
|
print "/* Conversion constants for HZ == $hz */\n";
|
|
print "\n";
|
|
print "#ifndef KERNEL_TIMECONST_H\n";
|
|
print "#define KERNEL_TIMECONST_H\n";
|
|
print "\n";
|
|
|
|
print "#include <linux/param.h>\n";
|
|
|
|
print "\n";
|
|
print "#if HZ != $hz\n";
|
|
print "#error \"kernel/timeconst.h has the wrong HZ value!\"\n";
|
|
print "#endif\n";
|
|
print "\n";
|
|
|
|
foreach $pfx ('HZ_TO_MSEC','MSEC_TO_HZ',
|
|
'HZ_TO_USEC','USEC_TO_HZ') {
|
|
foreach $bit (32, 64) {
|
|
foreach $suf ('MUL', 'ADJ', 'SHR') {
|
|
printf "#define %-23s %s\n",
|
|
"${pfx}_$suf$bit", shift(@val);
|
|
}
|
|
}
|
|
foreach $suf ('NUM', 'DEN') {
|
|
printf "#define %-23s %s\n",
|
|
"${pfx}_$suf", shift(@val);
|
|
}
|
|
}
|
|
|
|
print "\n";
|
|
print "#endif /* KERNEL_TIMECONST_H */\n";
|
|
}
|
|
|
|
($hz) = @ARGV;
|
|
|
|
# Use this to generate the %canned_values structure
|
|
if ($hz eq '--can') {
|
|
shift(@ARGV);
|
|
@hzlist = sort {$a <=> $b} (@ARGV);
|
|
|
|
print "# Precomputed values for systems without Math::BigInt\n";
|
|
print "# Generated by:\n";
|
|
print "# timeconst.pl --can ", join(' ', @hzlist), "\n";
|
|
print "\%canned_values = (\n";
|
|
my $pf = "\t";
|
|
foreach $hz (@hzlist) {
|
|
my @values = compute_values($hz);
|
|
print "$pf$hz => [\n";
|
|
while (scalar(@values)) {
|
|
my $bit;
|
|
foreach $bit (32, 64) {
|
|
my $m = shift(@values);
|
|
my $a = shift(@values);
|
|
my $s = shift(@values);
|
|
print "\t\t\'",$m,"\',\'",$a,"\',",$s,",\n";
|
|
}
|
|
my $n = shift(@values);
|
|
my $d = shift(@values);
|
|
print "\t\t",$n,',',$d,",\n";
|
|
}
|
|
print "\t]";
|
|
$pf = ', ';
|
|
}
|
|
print "\n);\n";
|
|
} else {
|
|
$hz += 0; # Force to number
|
|
if ($hz < 1) {
|
|
die "Usage: $0 HZ\n";
|
|
}
|
|
|
|
@val = @{$canned_values{$hz}};
|
|
if (!defined(@val)) {
|
|
@val = compute_values($hz);
|
|
}
|
|
output($hz, @val);
|
|
}
|
|
exit 0;
|