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diff --git a/arch/arm/mach-imx/smp_wfe.S b/arch/arm/mach-imx/smp_wfe.S
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+/*
+ * Copyright (C) 2015 Freescale Semiconductor, Inc. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that 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.
+ */
+
+#include <linux/linkage.h>
+#include <asm/smp_scu.h>
+#include "hardware.h"
+
+ .macro disable_l1_dcache
+
+ /*
+ * Flush all data from the L1 data cache before disabling
+ * SCTLR.C bit.
+ */
+ push {r0 - r10, lr}
+ ldr r7, =v7_flush_dcache_all
+ mov lr, pc
+ mov pc, r7
+ pop {r0 - r10, lr}
+
+ /* disable d-cache */
+ mrc p15, 0, r7, c1, c0, 0
+ bic r7, r7, #(1 << 2)
+ mcr p15, 0, r7, c1, c0, 0
+ dsb
+ isb
+
+ push {r0 - r10, lr}
+ ldr r7, =v7_flush_dcache_all
+ mov lr, pc
+ mov pc, r7
+ pop {r0 - r10, lr}
+
+ .endm
+
+#ifdef CONFIG_SMP
+ .align 3
+
+ENTRY(imx7_smp_wfe)
+ push {r4 - r11, lr}
+
+ dsb
+ isb
+
+ disable_l1_dcache
+
+ isb
+
+ /* Turn off SMP bit. */
+ mrc p15, 0, r8, c1, c0, 1
+ bic r8, r8, #0x40
+ mcr p15, 0, r8, c1, c0, 1
+
+ isb
+ /* Set flag of entering WFE. */
+ mov r7, #0xff
+ lsl r7, r7, r0
+ mov r6, #SCU_PM_DORMANT
+ lsl r6, r6, r0
+ ldr r8, [r1, #0x4]
+ bic r8, r8, r7
+ orr r6, r6, r8
+ str r6, [r1, #0x4]
+
+go_back_wfe:
+ wfe
+
+ /* Offset 0x0 stores busfeq done flag */
+ ldr r6, [r1]
+ cmp r6, #1
+ beq go_back_wfe
+
+ /* Turn ON SMP bit. */
+ mrc p15, 0, r8, c1, c0, 1
+ orr r8, r8, #0x40
+ mcr p15, 0, r8, c1, c0, 1
+
+ isb
+ /* Enable L1 data cache. */
+ mrc p15, 0, r8, c1, c0, 0
+ orr r8, r8, #0x4
+ mcr p15, 0, r8, c1, c0, 0
+ isb
+
+ /* Set flag of exiting WFE. */
+ mov r7, #0xff
+ lsl r7, r7, r0
+ mov r6, #SCU_PM_NORMAL
+ lsl r6, r6, r0
+ ldr r8, [r1, #0x4]
+ bic r8, r8, r7
+ orr r6, r6, r8
+ str r6, [r1, #0x4]
+
+ /* Pop all saved registers. */
+ pop {r4 - r11, lr}
+ mov pc, lr
+ .ltorg
+ENDPROC(imx7_smp_wfe)
+#endif