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+/*
+ * linux/arch/arm/kernel/fiqasm.S
+ *
+ * Derived from code originally in linux/arch/arm/kernel/fiq.c:
+ *
+ * Copyright (C) 1998 Russell King
+ * Copyright (C) 1998, 1999 Phil Blundell
+ * Copyright (C) 2011, Linaro Limited
+ *
+ * FIQ support written by Philip Blundell <philb@gnu.org>, 1998.
+ *
+ * FIQ support re-written by Russell King to be more generic
+ *
+ * v7/Thumb-2 compatibility modifications by Linaro Limited, 2011.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * Taking an interrupt in FIQ mode is death, so both these functions
+ * disable irqs for the duration.
+ */
+
+ENTRY(__set_fiq_regs)
+ mov r2, #PSR_I_BIT | PSR_F_BIT | FIQ_MODE
+ mrs r1, cpsr
+ msr cpsr_c, r2 @ select FIQ mode
+ mov r0, r0 @ avoid hazard prior to ARMv4
+ ldmia r0!, {r8 - r12}
+ ldr sp, [r0], #4
+ ldr lr, [r0]
+ msr cpsr_c, r1 @ return to SVC mode
+ mov r0, r0 @ avoid hazard prior to ARMv4
+ ret lr
+ENDPROC(__set_fiq_regs)
+
+ENTRY(__get_fiq_regs)
+ mov r2, #PSR_I_BIT | PSR_F_BIT | FIQ_MODE
+ mrs r1, cpsr
+ msr cpsr_c, r2 @ select FIQ mode
+ mov r0, r0 @ avoid hazard prior to ARMv4
+ stmia r0!, {r8 - r12}
+ str sp, [r0], #4
+ str lr, [r0]
+ msr cpsr_c, r1 @ return to SVC mode
+ mov r0, r0 @ avoid hazard prior to ARMv4
+ ret lr
+ENDPROC(__get_fiq_regs)