/*
* Copyright 2011 Calxeda, Inc.
* Based on PPC version Copyright 2007 MontaVista Software, Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#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)
{
#if __LINUX_ARM_ARCH__ >= 6
unsigned int *virt_addr = va;
unsigned int temp, temp2;
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: ldrex %0, [%2]\n"
" strex %1, %0, [%2]\n"
" teq %1, #0\n"
" bne 1b\n"
: "=&r"(temp), "=&r"(temp2)
: "r"(virt_addr)
: "cc");
}
#endif
}

#endif