edac.h

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/*
 * PPC EDAC common defs
 *
 * Author: Dave Jiang <[email protected]>
 *
 * 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