From: Stefan Reinauer <reina...@chromium.org>
Add functions to enable/disable the data cache.
Signed-off-by: Stefan Reinauer <reina...@chromium.org>
Signed-off-by: Simon Glass <s...@chromium.org>
---
arch/x86/cpu/interrupts.c | 8 +------
arch/x86/include/asm/cache.h | 47 ++++++++++++++++++++++++++++++++++++++++++
2 files changed, 48 insertions(+), 7 deletions(-)
diff --git a/arch/x86/cpu/interrupts.c b/arch/x86/cpu/interrupts.c
index 43ec3f8..710b653 100644
--- a/arch/x86/cpu/interrupts.c
+++ b/arch/x86/cpu/interrupts.c
@@ -28,6 +28,7 @@
*/
#include <common.h>
+#include <asm/cache.h>
#include <asm/interrupt.h>
#include <asm/io.h>
#include <asm/processor-flags.h>
@@ -50,13 +51,6 @@
*/
static unsigned long __force_order;
-static inline unsigned long read_cr0(void)
-{
- unsigned long val;
- asm volatile("mov %%cr0,%0\n\t" : "=r" (val), "=m" (__force_order));
- return val;
-}
-
static inline unsigned long read_cr2(void)
{
unsigned long val;
diff --git a/arch/x86/include/asm/cache.h b/arch/x86/include/asm/cache.h
index 87c9e0b..9836856 100644
--- a/arch/x86/include/asm/cache.h
+++ b/arch/x86/include/asm/cache.h
@@ -32,4 +32,51 @@
#define ARCH_DMA_MINALIGN 64
#endif
+/* The memory clobber prevents the GCC from reordering the read/write order
+ * of CR0
+ */
+static inline unsigned long read_cr0(void)
+{
+ unsigned long cr0;
+
+ asm volatile ("movl %%cr0, %0" : "=r" (cr0) : : "memory");
+ return cr0;
+}
+
+static inline void write_cr0(unsigned long cr0)
+{
+ asm volatile ("movl %0, %%cr0" : : "r" (cr0) : "memory");
+}
+
+static inline void wbinvd(void)
+{
+ asm volatile ("wbinvd" : : : "memory");
+}
+
+static inline void invd(void)
+{
+ asm volatile("invd" : : : "memory");
+}
+
+static inline void enable_cache(void)
+{
+ unsigned long cr0;
+
+ cr0 = read_cr0();
+ cr0 &= 0x9fffffff;
+ write_cr0(cr0);
+}
+
+static inline void disable_cache(void)
+{
+ /* Disable and write back the cache */
+ unsigned long cr0;
+
+ cr0 = read_cr0();
+ cr0 |= 0x40000000;
+ wbinvd();
+ write_cr0(cr0);
+ wbinvd();
+}
+
#endif /* __X86_CACHE_H__ */
--
1.7.7.3
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