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authorLinus Torvalds <torvalds@linux-foundation.org>2013-02-27 12:25:47 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2013-02-27 12:25:47 -0800
commit0ca7ffb356063c5ece847687da457dfe748612a2 (patch)
treef7858236ba482814c8cacf45447a3f96548a1688 /kernel/timeconst.bc
parent30acd906b02470e7eb346401de966a33864d9af4 (diff)
parent423a8155facf23719078ff63911c1e85ba40970b (diff)
Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild changes from Michal Marek: - Alias generation in modpost is cross-compile safe. - kernel/timeconst.h is now generated using a bc script instead of perl. - scripts/link-vmlinux.sh now works with an alternative $KCONFIG_CONFIG. - destination-y for exported headers is supported in Kbuild files again. - depmod is called with -P $CONFIG_SYMBOL_PREFIX on architectures that need it. - CONFIG_DEBUG_INFO_REDUCED disables var-tracking - scripts/setlocalversion works with too much translated locales ;) * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: kbuild: Fix reading of .config in link-vmlinux.sh kbuild: Unset language specific variables in setlocalversion script Kbuild: Disable var tracking with CONFIG_DEBUG_INFO_REDUCED depmod: pass -P $CONFIG_SYMBOL_PREFIX kbuild: Fix destination-y for installed headers scripts/link-vmlinux.sh: source variables from KCONFIG_CONFIG kernel: Replace timeconst.pl with a bc script mod/file2alias: make modalias generation safe for cross compiling
Diffstat (limited to 'kernel/timeconst.bc')
-rw-r--r--kernel/timeconst.bc108
1 files changed, 108 insertions, 0 deletions
diff --git a/kernel/timeconst.bc b/kernel/timeconst.bc
new file mode 100644
index 00000000000..511bdf2cafd
--- /dev/null
+++ b/kernel/timeconst.bc
@@ -0,0 +1,108 @@
+scale=0
+
+define gcd(a,b) {
+ auto t;
+ while (b) {
+ t = b;
+ b = a % b;
+ a = t;
+ }
+ return a;
+}
+
+/* Division by reciprocal multiplication. */
+define fmul(b,n,d) {
+ return (2^b*n+d-1)/d;
+}
+
+/* Adjustment factor when a ceiling value is used. Use as:
+ (imul * n) + (fmulxx * n + fadjxx) >> xx) */
+define fadj(b,n,d) {
+ auto v;
+ d = d/gcd(n,d);
+ v = 2^b*(d-1)/d;
+ return v;
+}
+
+/* Compute the appropriate mul/adj values as well as a shift count,
+ which brings the mul value into the range 2^b-1 <= x < 2^b. Such
+ a shift value will be correct in the signed integer range and off
+ by at most one in the upper half of the unsigned range. */
+define fmuls(b,n,d) {
+ auto s, m;
+ for (s = 0; 1; s++) {
+ m = fmul(s,n,d);
+ if (m >= 2^(b-1))
+ return s;
+ }
+ return 0;
+}
+
+define timeconst(hz) {
+ print "/* Automatically generated by kernel/timeconst.bc */\n"
+ print "/* Time conversion constants for HZ == ", hz, " */\n"
+ print "\n"
+
+ print "#ifndef KERNEL_TIMECONST_H\n"
+ print "#define KERNEL_TIMECONST_H\n\n"
+
+ print "#include <linux/param.h>\n"
+ print "#include <linux/types.h>\n\n"
+
+ print "#if HZ != ", hz, "\n"
+ print "#error \qkernel/timeconst.h has the wrong HZ value!\q\n"
+ print "#endif\n\n"
+
+ if (hz < 2) {
+ print "#error Totally bogus HZ value!\n"
+ } else {
+ s=fmuls(32,1000,hz)
+ obase=16
+ print "#define HZ_TO_MSEC_MUL32\tU64_C(0x", fmul(s,1000,hz), ")\n"
+ print "#define HZ_TO_MSEC_ADJ32\tU64_C(0x", fadj(s,1000,hz), ")\n"
+ obase=10
+ print "#define HZ_TO_MSEC_SHR32\t", s, "\n"
+
+ s=fmuls(32,hz,1000)
+ obase=16
+ print "#define MSEC_TO_HZ_MUL32\tU64_C(0x", fmul(s,hz,1000), ")\n"
+ print "#define MSEC_TO_HZ_ADJ32\tU64_C(0x", fadj(s,hz,1000), ")\n"
+ obase=10
+ print "#define MSEC_TO_HZ_SHR32\t", s, "\n"
+
+ obase=10
+ cd=gcd(hz,1000)
+ print "#define HZ_TO_MSEC_NUM\t\t", 1000/cd, "\n"
+ print "#define HZ_TO_MSEC_DEN\t\t", hz/cd, "\n"
+ print "#define MSEC_TO_HZ_NUM\t\t", hz/cd, "\n"
+ print "#define MSEC_TO_HZ_DEN\t\t", 1000/cd, "\n"
+ print "\n"
+
+ s=fmuls(32,1000000,hz)
+ obase=16
+ print "#define HZ_TO_USEC_MUL32\tU64_C(0x", fmul(s,1000000,hz), ")\n"
+ print "#define HZ_TO_USEC_ADJ32\tU64_C(0x", fadj(s,1000000,hz), ")\n"
+ obase=10
+ print "#define HZ_TO_USEC_SHR32\t", s, "\n"
+
+ s=fmuls(32,hz,1000000)
+ obase=16
+ print "#define USEC_TO_HZ_MUL32\tU64_C(0x", fmul(s,hz,1000000), ")\n"
+ print "#define USEC_TO_HZ_ADJ32\tU64_C(0x", fadj(s,hz,1000000), ")\n"
+ obase=10
+ print "#define USEC_TO_HZ_SHR32\t", s, "\n"
+
+ obase=10
+ cd=gcd(hz,1000000)
+ print "#define HZ_TO_USEC_NUM\t\t", 1000000/cd, "\n"
+ print "#define HZ_TO_USEC_DEN\t\t", hz/cd, "\n"
+ print "#define USEC_TO_HZ_NUM\t\t", hz/cd, "\n"
+ print "#define USEC_TO_HZ_DEN\t\t", 1000000/cd, "\n"
+ print "\n"
+
+ print "#endif /* KERNEL_TIMECONST_H */\n"
+ }
+ halt
+}
+
+timeconst(hz)