[PATCH 3/4] include asm-mips add missing edac h file

dougthompson
2007-07-25T20:47:47Z

From: Doug Thompson <dougthompson@xmission.h>

EDAC has a foundation to perform software memory scrubbing, but it
requires a per architecture (atomic_scrub) function for performing an atomic
update operation. Under X86, this is done with a

lock: add [addr],0

in the file asm-x86/edac.h

This patch provides the MIPS arch with that atomic function, atomic_scrub() in

asm-mips/edac.h

Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Doug Thompson <dougthompson@xmission.com>
---
edac.h | 35 +++++++++++++++++++++++++++++++++++
1 file changed, 35 insertions(+)

Index: linux-2.6.23-rc1/include/asm-mips/edac.h
===================================================================
--- /dev/null
+++ linux-2.6.23-rc1/include/asm-mips/edac.h
@@ -0,0 +1,35 @@
+#ifndef ASM_EDAC_H
+#define ASM_EDAC_H
+
+/* ECC atomic, DMA, SMP and interrupt safe scrub function */
+
+static __inline__ void atomic_scrub(void *va, u32 size)
+{
+ unsigned long *virt_addr = va;
+ unsigned long temp;
+ u32 i;
+
+ for (i = 0; i < size / sizeof(unsigned long); i++, virt_addr++) {
+
+ /*
+ * Very carefully read and write to memory atomically
+ * so we are interrupt, DMA and SMP safe.
+ *
+ * Intel: asm("lock; addl $0, %0"::"m"(*virt_addr));
+ */
+
+ __asm__ __volatile__ (
+ " .set mips3 \n"
+ "1: ll %0, %1 # atomic_add \n"
+ " ll %0, %1 # atomic_add \n"
+ " addu %0, $0 \n"
+ " sc %0, %1 \n"
+ " beqz %0, 1b \n"
+ " .set mips0 \n"
+ : "=&r" (temp), "=m" (*virt_addr)
+ : "m" (*virt_addr));
+
+ }
+}
+
+#endif