aboutsummaryrefslogtreecommitdiff
path: root/include/asm-i386
diff options
context:
space:
mode:
Diffstat (limited to 'include/asm-i386')
-rw-r--r--include/asm-i386/processor-cyrix.h30
-rw-r--r--include/asm-i386/processor.h11
2 files changed, 30 insertions, 11 deletions
diff --git a/include/asm-i386/processor-cyrix.h b/include/asm-i386/processor-cyrix.h
new file mode 100644
index 00000000000..97568ada1f9
--- /dev/null
+++ b/include/asm-i386/processor-cyrix.h
@@ -0,0 +1,30 @@
+/*
+ * NSC/Cyrix CPU indexed register access. Must be inlined instead of
+ * macros to ensure correct access ordering
+ * Access order is always 0x22 (=offset), 0x23 (=value)
+ *
+ * When using the old macros a line like
+ * setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88);
+ * gets expanded to:
+ * do {
+ * outb((CX86_CCR2), 0x22);
+ * outb((({
+ * outb((CX86_CCR2), 0x22);
+ * inb(0x23);
+ * }) | 0x88), 0x23);
+ * } while (0);
+ *
+ * which in fact violates the access order (= 0x22, 0x22, 0x23, 0x23).
+ */
+
+static inline u8 getCx86(u8 reg)
+{
+ outb(reg, 0x22);
+ return inb(0x23);
+}
+
+static inline void setCx86(u8 reg, u8 data)
+{
+ outb(reg, 0x22);
+ outb(data, 0x23);
+}
diff --git a/include/asm-i386/processor.h b/include/asm-i386/processor.h
index 48a7f69bb76..3845fe72383 100644
--- a/include/asm-i386/processor.h
+++ b/include/asm-i386/processor.h
@@ -168,17 +168,6 @@ static inline void clear_in_cr4 (unsigned long mask)
write_cr4(cr4);
}
-/*
- * NSC/Cyrix CPU indexed register access macros
- */
-
-#define getCx86(reg) ({ outb((reg), 0x22); inb(0x23); })
-
-#define setCx86(reg, data) do { \
- outb((reg), 0x22); \
- outb((data), 0x23); \
-} while (0)
-
/* Stop speculative execution */
static inline void sync_core(void)
{