1 /*
2 * linux/arch/arm/kernel/fiqasm.S
3 *
4 * Derived from code originally in linux/arch/arm/kernel/fiq.c:
5 *
6 * Copyright (C) 1998 Russell King
7 * Copyright (C) 1998, 1999 Phil Blundell
8 * Copyright (C) 2011, Linaro Limited
9 *
10 * FIQ support written by Philip Blundell <philb@gnu.org>, 1998.
11 *
12 * FIQ support re-written by Russell King to be more generic
13 *
14 * v7/Thumb-2 compatibility modifications by Linaro Limited, 2011.
15 */
16
17 #include <linux/linkage.h>
18 #include <asm/assembler.h>
19
20 /*
21 * Taking an interrupt in FIQ mode is death, so both these functions
22 * disable irqs for the duration.
23 */
24
25 ENTRY(__set_fiq_regs)
26 mov r2, #PSR_I_BIT | PSR_F_BIT | FIQ_MODE
27 mrs r1, cpsr
28 msr cpsr_c, r2 @ select FIQ mode
29 mov r0, r0 @ avoid hazard prior to ARMv4
30 ldmia r0!, {r8 - r12}
31 ldr sp, [r0], #4
32 ldr lr, [r0]
33 msr cpsr_c, r1 @ return to SVC mode
34 mov r0, r0 @ avoid hazard prior to ARMv4
35 ret lr
36 ENDPROC(__set_fiq_regs)
37
38 ENTRY(__get_fiq_regs)
39 mov r2, #PSR_I_BIT | PSR_F_BIT | FIQ_MODE
40 mrs r1, cpsr
41 msr cpsr_c, r2 @ select FIQ mode
42 mov r0, r0 @ avoid hazard prior to ARMv4
43 stmia r0!, {r8 - r12}
44 str sp, [r0], #4
45 str lr, [r0]
46 msr cpsr_c, r1 @ return to SVC mode
47 mov r0, r0 @ avoid hazard prior to ARMv4
48 ret lr
49 ENDPROC(__get_fiq_regs)