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-rw-r--r--src/arch/i386/include/arch/smp/atomic.h69
-rw-r--r--src/arch/i386/include/arch/smp/spinlock.h57
-rw-r--r--src/arch/i386/lib/c_start.S4
3 files changed, 128 insertions, 2 deletions
diff --git a/src/arch/i386/include/arch/smp/atomic.h b/src/arch/i386/include/arch/smp/atomic.h
new file mode 100644
index 0000000000..7b68377c22
--- /dev/null
+++ b/src/arch/i386/include/arch/smp/atomic.h
@@ -0,0 +1,69 @@
+#ifndef ARCH_SMP_ATOMIC_H
+#define ARCH_SMP_ATOMIC_H
+
+/*
+ * Make sure gcc doesn't try to be clever and move things around
+ * on us. We need to use _exactly_ the address the user gave us,
+ * not some alias that contains the same information.
+ */
+typedef struct { volatile int counter; } atomic_t;
+
+#define ATOMIC_INIT(i) { (i) }
+
+/*
+ * Atomic operations that C can't guarantee us. Useful for
+ * resource counting etc..
+ */
+
+/**
+ * atomic_read - read atomic variable
+ * @v: pointer of type atomic_t
+ *
+ * Atomically reads the value of @v. Note that the guaranteed
+ * useful range of an atomic_t is only 24 bits.
+ */
+#define atomic_read(v) ((v)->counter)
+
+/**
+ * atomic_set - set atomic variable
+ * @v: pointer of type atomic_t
+ * @i: required value
+ *
+ * Atomically sets the value of @v to @i. Note that the guaranteed
+ * useful range of an atomic_t is only 24 bits.
+ */
+#define atomic_set(v,i) (((v)->counter) = (i))
+
+/**
+ * atomic_inc - increment atomic variable
+ * @v: pointer of type atomic_t
+ *
+ * Atomically increments @v by 1. Note that the guaranteed
+ * useful range of an atomic_t is only 24 bits.
+ */
+static __inline__ void atomic_inc(atomic_t *v)
+{
+ __asm__ __volatile__(
+ "lock ; incl %0"
+ :"=m" (v->counter)
+ :"m" (v->counter));
+}
+
+/**
+ * atomic_dec - decrement atomic variable
+ * @v: pointer of type atomic_t
+ *
+ * Atomically decrements @v by 1. Note that the guaranteed
+ * useful range of an atomic_t is only 24 bits.
+ */
+static __inline__ void atomic_dec(atomic_t *v)
+{
+ __asm__ __volatile__(
+ "lock ; decl %0"
+ :"=m" (v->counter)
+ :"m" (v->counter));
+}
+
+
+
+#endif /* ARCH_SMP_ATOMIC_H */
diff --git a/src/arch/i386/include/arch/smp/spinlock.h b/src/arch/i386/include/arch/smp/spinlock.h
new file mode 100644
index 0000000000..d0cc11c6a7
--- /dev/null
+++ b/src/arch/i386/include/arch/smp/spinlock.h
@@ -0,0 +1,57 @@
+#ifndef ARCH_SMP_SPINLOCK_H
+#define ARCH_SMP_SPINLOCK_H
+
+/*
+ * Your basic SMP spinlocks, allowing only a single CPU anywhere
+ */
+
+typedef struct {
+ volatile unsigned int lock;
+} spinlock_t;
+
+
+#define SPIN_LOCK_UNLOCKED (spinlock_t) { 1 }
+
+/*
+ * Simple spin lock operations. There are two variants, one clears IRQ's
+ * on the local processor, one does not.
+ *
+ * We make no fairness assumptions. They have a cost.
+ */
+#define barrier() __asm__ __volatile__("": : :"memory")
+#define spin_is_locked(x) (*(volatile char *)(&(x)->lock) <= 0)
+#define spin_unlock_wait(x) do { barrier(); } while(spin_is_locked(x))
+
+#define spin_lock_string \
+ "\n1:\t" \
+ "lock ; decb %0\n\t" \
+ "js 2f\n" \
+ ".section .text.lock,\"ax\"\n" \
+ "2:\t" \
+ "cmpb $0,%0\n\t" \
+ "rep;nop\n\t" \
+ "jle 2b\n\t" \
+ "jmp 1b\n" \
+ ".previous"
+
+/*
+ * This works. Despite all the confusion.
+ */
+#define spin_unlock_string \
+ "movb $1,%0"
+
+static inline void spin_lock(spinlock_t *lock)
+{
+ __asm__ __volatile__(
+ spin_lock_string
+ :"=m" (lock->lock) : : "memory");
+}
+
+static inline void spin_unlock(spinlock_t *lock)
+{
+ __asm__ __volatile__(
+ spin_unlock_string
+ :"=m" (lock->lock) : : "memory");
+}
+
+#endif /* ARCH_SMP_SPINLOCK_H */
diff --git a/src/arch/i386/lib/c_start.S b/src/arch/i386/lib/c_start.S
index 48c1514a1e..dfe57dd7f0 100644
--- a/src/arch/i386/lib/c_start.S
+++ b/src/arch/i386/lib/c_start.S
@@ -1,6 +1,6 @@
#include <arch/asm.h>
#include <arch/intel.h>
-#ifdef SMP
+#ifdef CONFIG_SMP
#include <cpu/p6/apic.h>
#endif
.section ".text"
@@ -39,7 +39,7 @@ _start:
/* set new stack */
movl $_estack, %esp
-#ifdef SMP
+#ifdef CONFIG_SMP
/* Get the cpu id */
movl $APIC_DEFAULT_BASE, %edi
movl APIC_ID(%edi), %eax