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-rw-r--r--src/arch/i386/include/div64.h48
-rw-r--r--src/arch/i386/smp/mpspec.c2
2 files changed, 49 insertions, 1 deletions
diff --git a/src/arch/i386/include/div64.h b/src/arch/i386/include/div64.h
new file mode 100644
index 0000000000..28ed8b296a
--- /dev/null
+++ b/src/arch/i386/include/div64.h
@@ -0,0 +1,48 @@
+#ifndef __I386_DIV64
+#define __I386_DIV64
+
+/*
+ * do_div() is NOT a C function. It wants to return
+ * two values (the quotient and the remainder), but
+ * since that doesn't work very well in C, what it
+ * does is:
+ *
+ * - modifies the 64-bit dividend _in_place_
+ * - returns the 32-bit remainder
+ *
+ * This ends up being the most efficient "calling
+ * convention" on x86.
+ */
+#define do_div(n,base) ({ \
+ unsigned long __upper, __low, __high, __mod, __base; \
+ __base = (base); \
+ asm("":"=a" (__low), "=d" (__high):"A" (n)); \
+ __upper = __high; \
+ if (__high) { \
+ __upper = __high % (__base); \
+ __high = __high / (__base); \
+ } \
+ asm("divl %2":"=a" (__low), "=d" (__mod):"rm" (__base), "0" (__low), "1" (__upper)); \
+ asm("":"=A" (n):"a" (__low),"d" (__high)); \
+ __mod; \
+})
+
+/*
+ * (long)X = ((long long)divs) / (long)div
+ * (long)rem = ((long long)divs) % (long)div
+ *
+ * Warning, this will do an exception if X overflows.
+ */
+#define div_long_long_rem(a,b,c) div_ll_X_l_rem(a,b,c)
+
+extern inline long
+div_ll_X_l_rem(long long divs, long div, long *rem)
+{
+ long dum2;
+ __asm__("divl %2":"=a"(dum2), "=d"(*rem)
+ : "rm"(div), "A"(divs));
+
+ return dum2;
+
+}
+#endif
diff --git a/src/arch/i386/smp/mpspec.c b/src/arch/i386/smp/mpspec.c
index c674cf58f5..daeb78435d 100644
--- a/src/arch/i386/smp/mpspec.c
+++ b/src/arch/i386/smp/mpspec.c
@@ -121,7 +121,7 @@ void smp_write_processors(struct mp_config_table *mc)
}
cpu_flag = MPC_CPU_ENABLED;
if (boot_apic_id == cpu->path.u.apic.apic_id) {
- cpu_flag = MPC_CPU_ENABLED;
+ cpu_flag = MPC_CPU_ENABLED | MPC_CPU_BOOTPROCESSOR;
}
smp_write_processor(mc,
cpu->path.u.apic.apic_id, apic_version,