From 723ec731de880a76a004a304b62bf8d0f96435d8 Mon Sep 17 00:00:00 2001 From: Dave Jiang Date: Fri, 2 Mar 2007 13:36:21 -0700 Subject: [PATCH] [POWERPC] EDAC ECC software scrubber Implements the per arch atomic_scrub() that EDAC uses for software ECC scrubbing. It reads memory and then writes back the original value, allowing the hardware to detect and correct memory errors. Signed-off-by: Dave Jiang Signed-off-by: Paul Mackerras --- include/asm-powerpc/edac.h | 40 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100644 include/asm-powerpc/edac.h diff --git a/include/asm-powerpc/edac.h b/include/asm-powerpc/edac.h new file mode 100644 index 000000000000..6ead88bbfbb8 --- /dev/null +++ b/include/asm-powerpc/edac.h @@ -0,0 +1,40 @@ +/* + * PPC EDAC common defs + * + * Author: Dave Jiang + * + * 2007 (c) MontaVista Software, Inc. This file is licensed under + * the terms of the GNU General Public License version 2. This program + * is licensed "as is" without any warranty of any kind, whether express + * or implied. + */ +#ifndef ASM_EDAC_H +#define ASM_EDAC_H +/* + * ECC atomic, DMA, SMP and interrupt safe scrub function. + * Implements the per arch atomic_scrub() that EDAC use for software + * ECC scrubbing. It reads memory and then writes back the original + * value, allowing the hardware to detect and correct memory errors. + */ +static __inline__ void atomic_scrub(void *va, u32 size) +{ + unsigned int *virt_addr = va; + unsigned int temp; + unsigned int i; + + for (i = 0; i < size / sizeof(*virt_addr); i++, virt_addr++) { + /* Very carefully read and write to memory atomically + * so we are interrupt, DMA and SMP safe. + */ + __asm__ __volatile__ ("\n\ + 1: lwarx %0,0,%1\n\ + stwcx. %0,0,%1\n\ + bne- 1b\n\ + isync" + : "=&r"(temp) + : "r"(virt_addr) + : "cr0", "memory"); + } +} + +#endif