xref: /linux/arch/arm/include/asm/assembler.h (revision d59fec29b131f30b27343d54bdf1071ee98eda8e)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  *  arch/arm/include/asm/assembler.h
4  *
5  *  Copyright (C) 1996-2000 Russell King
6  *
7  *  This file contains arm architecture specific defines
8  *  for the different processors.
9  *
10  *  Do not include any C declarations in this file - it is included by
11  *  assembler source.
12  */
13 #ifndef __ASM_ASSEMBLER_H__
14 #define __ASM_ASSEMBLER_H__
15 
16 #ifndef __ASSEMBLY__
17 #error "Only include this from assembly code"
18 #endif
19 
20 #include <asm/ptrace.h>
21 #include <asm/opcodes-virt.h>
22 #include <asm/asm-offsets.h>
23 #include <asm/page.h>
24 #include <asm/thread_info.h>
25 #include <asm/uaccess-asm.h>
26 
27 #define IOMEM(x)	(x)
28 
29 /*
30  * Endian independent macros for shifting bytes within registers.
31  */
32 #ifndef __ARMEB__
33 #define lspull          lsr
34 #define lspush          lsl
35 #define get_byte_0      lsl #0
36 #define get_byte_1	lsr #8
37 #define get_byte_2	lsr #16
38 #define get_byte_3	lsr #24
39 #define put_byte_0      lsl #0
40 #define put_byte_1	lsl #8
41 #define put_byte_2	lsl #16
42 #define put_byte_3	lsl #24
43 #else
44 #define lspull          lsl
45 #define lspush          lsr
46 #define get_byte_0	lsr #24
47 #define get_byte_1	lsr #16
48 #define get_byte_2	lsr #8
49 #define get_byte_3      lsl #0
50 #define put_byte_0	lsl #24
51 #define put_byte_1	lsl #16
52 #define put_byte_2	lsl #8
53 #define put_byte_3      lsl #0
54 #endif
55 
56 /* Select code for any configuration running in BE8 mode */
57 #ifdef CONFIG_CPU_ENDIAN_BE8
58 #define ARM_BE8(code...) code
59 #else
60 #define ARM_BE8(code...)
61 #endif
62 
63 /*
64  * Data preload for architectures that support it
65  */
66 #if __LINUX_ARM_ARCH__ >= 5
67 #define PLD(code...)	code
68 #else
69 #define PLD(code...)
70 #endif
71 
72 /*
73  * This can be used to enable code to cacheline align the destination
74  * pointer when bulk writing to memory.  Experiments on StrongARM and
75  * XScale didn't show this a worthwhile thing to do when the cache is not
76  * set to write-allocate (this would need further testing on XScale when WA
77  * is used).
78  *
79  * On Feroceon there is much to gain however, regardless of cache mode.
80  */
81 #ifdef CONFIG_CPU_FEROCEON
82 #define CALGN(code...) code
83 #else
84 #define CALGN(code...)
85 #endif
86 
87 #define IMM12_MASK 0xfff
88 
89 /* the frame pointer used for stack unwinding */
90 ARM(	fpreg	.req	r11	)
91 THUMB(	fpreg	.req	r7	)
92 
93 /*
94  * Enable and disable interrupts
95  */
96 #if __LINUX_ARM_ARCH__ >= 6
97 	.macro	disable_irq_notrace
98 	cpsid	i
99 	.endm
100 
101 	.macro	enable_irq_notrace
102 	cpsie	i
103 	.endm
104 #else
105 	.macro	disable_irq_notrace
106 	msr	cpsr_c, #PSR_I_BIT | SVC_MODE
107 	.endm
108 
109 	.macro	enable_irq_notrace
110 	msr	cpsr_c, #SVC_MODE
111 	.endm
112 #endif
113 
114 #if __LINUX_ARM_ARCH__ < 7
115 	.macro	dsb, args
116 	mcr	p15, 0, r0, c7, c10, 4
117 	.endm
118 
119 	.macro	isb, args
120 	mcr	p15, 0, r0, c7, c5, 4
121 	.endm
122 #endif
123 
124 	.macro asm_trace_hardirqs_off, save=1
125 #if defined(CONFIG_TRACE_IRQFLAGS)
126 	.if \save
127 	stmdb   sp!, {r0-r3, ip, lr}
128 	.endif
129 	bl	trace_hardirqs_off
130 	.if \save
131 	ldmia	sp!, {r0-r3, ip, lr}
132 	.endif
133 #endif
134 	.endm
135 
136 	.macro asm_trace_hardirqs_on, cond=al, save=1
137 #if defined(CONFIG_TRACE_IRQFLAGS)
138 	/*
139 	 * actually the registers should be pushed and pop'd conditionally, but
140 	 * after bl the flags are certainly clobbered
141 	 */
142 	.if \save
143 	stmdb   sp!, {r0-r3, ip, lr}
144 	.endif
145 	bl\cond	trace_hardirqs_on
146 	.if \save
147 	ldmia	sp!, {r0-r3, ip, lr}
148 	.endif
149 #endif
150 	.endm
151 
152 	.macro disable_irq, save=1
153 	disable_irq_notrace
154 	asm_trace_hardirqs_off \save
155 	.endm
156 
157 	.macro enable_irq
158 	asm_trace_hardirqs_on
159 	enable_irq_notrace
160 	.endm
161 /*
162  * Save the current IRQ state and disable IRQs.  Note that this macro
163  * assumes FIQs are enabled, and that the processor is in SVC mode.
164  */
165 	.macro	save_and_disable_irqs, oldcpsr
166 #ifdef CONFIG_CPU_V7M
167 	mrs	\oldcpsr, primask
168 #else
169 	mrs	\oldcpsr, cpsr
170 #endif
171 	disable_irq
172 	.endm
173 
174 	.macro	save_and_disable_irqs_notrace, oldcpsr
175 #ifdef CONFIG_CPU_V7M
176 	mrs	\oldcpsr, primask
177 #else
178 	mrs	\oldcpsr, cpsr
179 #endif
180 	disable_irq_notrace
181 	.endm
182 
183 /*
184  * Restore interrupt state previously stored in a register.  We don't
185  * guarantee that this will preserve the flags.
186  */
187 	.macro	restore_irqs_notrace, oldcpsr
188 #ifdef CONFIG_CPU_V7M
189 	msr	primask, \oldcpsr
190 #else
191 	msr	cpsr_c, \oldcpsr
192 #endif
193 	.endm
194 
195 	.macro restore_irqs, oldcpsr
196 	tst	\oldcpsr, #PSR_I_BIT
197 	asm_trace_hardirqs_on cond=eq
198 	restore_irqs_notrace \oldcpsr
199 	.endm
200 
201 /*
202  * Assembly version of "adr rd, BSYM(sym)".  This should only be used to
203  * reference local symbols in the same assembly file which are to be
204  * resolved by the assembler.  Other usage is undefined.
205  */
206 	.irp	c,,eq,ne,cs,cc,mi,pl,vs,vc,hi,ls,ge,lt,gt,le,hs,lo
207 	.macro	badr\c, rd, sym
208 #ifdef CONFIG_THUMB2_KERNEL
209 	adr\c	\rd, \sym + 1
210 #else
211 	adr\c	\rd, \sym
212 #endif
213 	.endm
214 	.endr
215 
216 /*
217  * Get current thread_info.
218  */
219 	.macro	get_thread_info, rd
220 	/* thread_info is the first member of struct task_struct */
221 	get_current \rd
222 	.endm
223 
224 /*
225  * Increment/decrement the preempt count.
226  */
227 #ifdef CONFIG_PREEMPT_COUNT
228 	.macro	inc_preempt_count, ti, tmp
229 	ldr	\tmp, [\ti, #TI_PREEMPT]	@ get preempt count
230 	add	\tmp, \tmp, #1			@ increment it
231 	str	\tmp, [\ti, #TI_PREEMPT]
232 	.endm
233 
234 	.macro	dec_preempt_count, ti, tmp
235 	ldr	\tmp, [\ti, #TI_PREEMPT]	@ get preempt count
236 	sub	\tmp, \tmp, #1			@ decrement it
237 	str	\tmp, [\ti, #TI_PREEMPT]
238 	.endm
239 #else
240 	.macro	inc_preempt_count, ti, tmp
241 	.endm
242 
243 	.macro	dec_preempt_count, ti, tmp
244 	.endm
245 #endif
246 
247 #define USERL(l, x...)				\
248 9999:	x;					\
249 	.pushsection __ex_table,"a";		\
250 	.align	3;				\
251 	.long	9999b,l;			\
252 	.popsection
253 
254 #define USER(x...)	USERL(9001f, x)
255 
256 #ifdef CONFIG_SMP
257 #define ALT_SMP(instr...)					\
258 9998:	instr
259 /*
260  * Note: if you get assembler errors from ALT_UP() when building with
261  * CONFIG_THUMB2_KERNEL, you almost certainly need to use
262  * ALT_SMP( W(instr) ... )
263  */
264 #define ALT_UP(instr...)					\
265 	.pushsection ".alt.smp.init", "a"			;\
266 	.align	2						;\
267 	.long	9998b - .					;\
268 9997:	instr							;\
269 	.if . - 9997b == 2					;\
270 		nop						;\
271 	.endif							;\
272 	.if . - 9997b != 4					;\
273 		.error "ALT_UP() content must assemble to exactly 4 bytes";\
274 	.endif							;\
275 	.popsection
276 #define ALT_UP_B(label)					\
277 	.pushsection ".alt.smp.init", "a"			;\
278 	.align	2						;\
279 	.long	9998b - .					;\
280 	W(b)	. + (label - 9998b)					;\
281 	.popsection
282 #else
283 #define ALT_SMP(instr...)
284 #define ALT_UP(instr...) instr
285 #define ALT_UP_B(label) b label
286 #endif
287 
288 	/*
289 	 * this_cpu_offset - load the per-CPU offset of this CPU into
290 	 * 		     register 'rd'
291 	 */
292 	.macro		this_cpu_offset, rd:req
293 #ifdef CONFIG_SMP
294 ALT_SMP(mrc		p15, 0, \rd, c13, c0, 4)
295 #ifdef CONFIG_CPU_V6
296 ALT_UP_B(.L1_\@)
297 .L0_\@:
298 	.subsection	1
299 .L1_\@: ldr_va		\rd, __per_cpu_offset
300 	b		.L0_\@
301 	.previous
302 #endif
303 #else
304 	mov		\rd, #0
305 #endif
306 	.endm
307 
308 	/*
309 	 * set_current - store the task pointer of this CPU's current task
310 	 */
311 	.macro		set_current, rn:req, tmp:req
312 #if defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP)
313 9998:	mcr		p15, 0, \rn, c13, c0, 3		@ set TPIDRURO register
314 #ifdef CONFIG_CPU_V6
315 ALT_UP_B(.L0_\@)
316 	.subsection	1
317 .L0_\@: str_va		\rn, __current, \tmp
318 	b		.L1_\@
319 	.previous
320 .L1_\@:
321 #endif
322 #else
323 	str_va		\rn, __current, \tmp
324 #endif
325 	.endm
326 
327 	/*
328 	 * get_current - load the task pointer of this CPU's current task
329 	 */
330 	.macro		get_current, rd:req
331 #if defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP)
332 9998:	mrc		p15, 0, \rd, c13, c0, 3		@ get TPIDRURO register
333 #ifdef CONFIG_CPU_V6
334 ALT_UP_B(.L0_\@)
335 	.subsection	1
336 .L0_\@: ldr_va		\rd, __current
337 	b		.L1_\@
338 	.previous
339 .L1_\@:
340 #endif
341 #else
342 	ldr_va		\rd, __current
343 #endif
344 	.endm
345 
346 	/*
347 	 * reload_current - reload the task pointer of this CPU's current task
348 	 *		    into the TLS register
349 	 */
350 	.macro		reload_current, t1:req, t2:req
351 #if defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP)
352 #ifdef CONFIG_CPU_V6
353 ALT_SMP(nop)
354 ALT_UP_B(.L0_\@)
355 #endif
356 	ldr_this_cpu	\t1, __entry_task, \t1, \t2
357 	mcr		p15, 0, \t1, c13, c0, 3		@ store in TPIDRURO
358 .L0_\@:
359 #endif
360 	.endm
361 
362 /*
363  * Instruction barrier
364  */
365 	.macro	instr_sync
366 #if __LINUX_ARM_ARCH__ >= 7
367 	isb
368 #elif __LINUX_ARM_ARCH__ == 6
369 	mcr	p15, 0, r0, c7, c5, 4
370 #endif
371 	.endm
372 
373 /*
374  * SMP data memory barrier
375  */
376 	.macro	smp_dmb mode
377 #ifdef CONFIG_SMP
378 #if __LINUX_ARM_ARCH__ >= 7
379 	.ifeqs "\mode","arm"
380 	ALT_SMP(dmb	ish)
381 	.else
382 	ALT_SMP(W(dmb)	ish)
383 	.endif
384 #elif __LINUX_ARM_ARCH__ == 6
385 	ALT_SMP(mcr	p15, 0, r0, c7, c10, 5)	@ dmb
386 #else
387 #error Incompatible SMP platform
388 #endif
389 	.ifeqs "\mode","arm"
390 	ALT_UP(nop)
391 	.else
392 	ALT_UP(W(nop))
393 	.endif
394 #endif
395 	.endm
396 
397 #if defined(CONFIG_CPU_V7M)
398 	/*
399 	 * setmode is used to assert to be in svc mode during boot. For v7-M
400 	 * this is done in __v7m_setup, so setmode can be empty here.
401 	 */
402 	.macro	setmode, mode, reg
403 	.endm
404 #elif defined(CONFIG_THUMB2_KERNEL)
405 	.macro	setmode, mode, reg
406 	mov	\reg, #\mode
407 	msr	cpsr_c, \reg
408 	.endm
409 #else
410 	.macro	setmode, mode, reg
411 	msr	cpsr_c, #\mode
412 	.endm
413 #endif
414 
415 /*
416  * Helper macro to enter SVC mode cleanly and mask interrupts. reg is
417  * a scratch register for the macro to overwrite.
418  *
419  * This macro is intended for forcing the CPU into SVC mode at boot time.
420  * you cannot return to the original mode.
421  */
422 .macro safe_svcmode_maskall reg:req
423 #if __LINUX_ARM_ARCH__ >= 6 && !defined(CONFIG_CPU_V7M)
424 	mrs	\reg , cpsr
425 	eor	\reg, \reg, #HYP_MODE
426 	tst	\reg, #MODE_MASK
427 	bic	\reg , \reg , #MODE_MASK
428 	orr	\reg , \reg , #PSR_I_BIT | PSR_F_BIT | SVC_MODE
429 THUMB(	orr	\reg , \reg , #PSR_T_BIT	)
430 	bne	1f
431 	orr	\reg, \reg, #PSR_A_BIT
432 	badr	lr, 2f
433 	msr	spsr_cxsf, \reg
434 	__MSR_ELR_HYP(14)
435 	__ERET
436 1:	msr	cpsr_c, \reg
437 2:
438 #else
439 /*
440  * workaround for possibly broken pre-v6 hardware
441  * (akita, Sharp Zaurus C-1000, PXA270-based)
442  */
443 	setmode	PSR_F_BIT | PSR_I_BIT | SVC_MODE, \reg
444 #endif
445 .endm
446 
447 /*
448  * STRT/LDRT access macros with ARM and Thumb-2 variants
449  */
450 #ifdef CONFIG_THUMB2_KERNEL
451 
452 	.macro	usraccoff, instr, reg, ptr, inc, off, cond, abort, t=TUSER()
453 9999:
454 	.if	\inc == 1
455 	\instr\()b\t\cond\().w \reg, [\ptr, #\off]
456 	.elseif	\inc == 4
457 	\instr\t\cond\().w \reg, [\ptr, #\off]
458 	.else
459 	.error	"Unsupported inc macro argument"
460 	.endif
461 
462 	.pushsection __ex_table,"a"
463 	.align	3
464 	.long	9999b, \abort
465 	.popsection
466 	.endm
467 
468 	.macro	usracc, instr, reg, ptr, inc, cond, rept, abort
469 	@ explicit IT instruction needed because of the label
470 	@ introduced by the USER macro
471 	.ifnc	\cond,al
472 	.if	\rept == 1
473 	itt	\cond
474 	.elseif	\rept == 2
475 	ittt	\cond
476 	.else
477 	.error	"Unsupported rept macro argument"
478 	.endif
479 	.endif
480 
481 	@ Slightly optimised to avoid incrementing the pointer twice
482 	usraccoff \instr, \reg, \ptr, \inc, 0, \cond, \abort
483 	.if	\rept == 2
484 	usraccoff \instr, \reg, \ptr, \inc, \inc, \cond, \abort
485 	.endif
486 
487 	add\cond \ptr, #\rept * \inc
488 	.endm
489 
490 #else	/* !CONFIG_THUMB2_KERNEL */
491 
492 	.macro	usracc, instr, reg, ptr, inc, cond, rept, abort, t=TUSER()
493 	.rept	\rept
494 9999:
495 	.if	\inc == 1
496 	\instr\()b\t\cond \reg, [\ptr], #\inc
497 	.elseif	\inc == 4
498 	\instr\t\cond \reg, [\ptr], #\inc
499 	.else
500 	.error	"Unsupported inc macro argument"
501 	.endif
502 
503 	.pushsection __ex_table,"a"
504 	.align	3
505 	.long	9999b, \abort
506 	.popsection
507 	.endr
508 	.endm
509 
510 #endif	/* CONFIG_THUMB2_KERNEL */
511 
512 	.macro	strusr, reg, ptr, inc, cond=al, rept=1, abort=9001f
513 	usracc	str, \reg, \ptr, \inc, \cond, \rept, \abort
514 	.endm
515 
516 	.macro	ldrusr, reg, ptr, inc, cond=al, rept=1, abort=9001f
517 	usracc	ldr, \reg, \ptr, \inc, \cond, \rept, \abort
518 	.endm
519 
520 /* Utility macro for declaring string literals */
521 	.macro	string name:req, string
522 	.type \name , #object
523 \name:
524 	.asciz "\string"
525 	.size \name , . - \name
526 	.endm
527 
528 	.irp	c,,eq,ne,cs,cc,mi,pl,vs,vc,hi,ls,ge,lt,gt,le,hs,lo
529 	.macro	ret\c, reg
530 #if __LINUX_ARM_ARCH__ < 6
531 	mov\c	pc, \reg
532 #else
533 	.ifeqs	"\reg", "lr"
534 	bx\c	\reg
535 	.else
536 	mov\c	pc, \reg
537 	.endif
538 #endif
539 	.endm
540 	.endr
541 
542 	.macro	ret.w, reg
543 	ret	\reg
544 #ifdef CONFIG_THUMB2_KERNEL
545 	nop
546 #endif
547 	.endm
548 
549 	.macro	bug, msg, line
550 #ifdef CONFIG_THUMB2_KERNEL
551 1:	.inst	0xde02
552 #else
553 1:	.inst	0xe7f001f2
554 #endif
555 #ifdef CONFIG_DEBUG_BUGVERBOSE
556 	.pushsection .rodata.str, "aMS", %progbits, 1
557 2:	.asciz	"\msg"
558 	.popsection
559 	.pushsection __bug_table, "aw"
560 	.align	2
561 	.word	1b, 2b
562 	.hword	\line
563 	.popsection
564 #endif
565 	.endm
566 
567 #ifdef CONFIG_KPROBES
568 #define _ASM_NOKPROBE(entry)				\
569 	.pushsection "_kprobe_blacklist", "aw" ;	\
570 	.balign 4 ;					\
571 	.long entry;					\
572 	.popsection
573 #else
574 #define _ASM_NOKPROBE(entry)
575 #endif
576 
577 	.macro		__adldst_l, op, reg, sym, tmp, c
578 	.if		__LINUX_ARM_ARCH__ < 7
579 	ldr\c		\tmp, .La\@
580 	.subsection	1
581 	.align		2
582 .La\@:	.long		\sym - .Lpc\@
583 	.previous
584 	.else
585 	.ifnb		\c
586  THUMB(	ittt		\c			)
587 	.endif
588 	movw\c		\tmp, #:lower16:\sym - .Lpc\@
589 	movt\c		\tmp, #:upper16:\sym - .Lpc\@
590 	.endif
591 
592 #ifndef CONFIG_THUMB2_KERNEL
593 	.set		.Lpc\@, . + 8			// PC bias
594 	.ifc		\op, add
595 	add\c		\reg, \tmp, pc
596 	.else
597 	\op\c		\reg, [pc, \tmp]
598 	.endif
599 #else
600 .Lb\@:	add\c		\tmp, \tmp, pc
601 	/*
602 	 * In Thumb-2 builds, the PC bias depends on whether we are currently
603 	 * emitting into a .arm or a .thumb section. The size of the add opcode
604 	 * above will be 2 bytes when emitting in Thumb mode and 4 bytes when
605 	 * emitting in ARM mode, so let's use this to account for the bias.
606 	 */
607 	.set		.Lpc\@, . + (. - .Lb\@)
608 
609 	.ifnc		\op, add
610 	\op\c		\reg, [\tmp]
611 	.endif
612 #endif
613 	.endm
614 
615 	/*
616 	 * mov_l - move a constant value or [relocated] address into a register
617 	 */
618 	.macro		mov_l, dst:req, imm:req, cond
619 	.if		__LINUX_ARM_ARCH__ < 7
620 	ldr\cond	\dst, =\imm
621 	.else
622 	movw\cond	\dst, #:lower16:\imm
623 	movt\cond	\dst, #:upper16:\imm
624 	.endif
625 	.endm
626 
627 	/*
628 	 * adr_l - adr pseudo-op with unlimited range
629 	 *
630 	 * @dst: destination register
631 	 * @sym: name of the symbol
632 	 * @cond: conditional opcode suffix
633 	 */
634 	.macro		adr_l, dst:req, sym:req, cond
635 	__adldst_l	add, \dst, \sym, \dst, \cond
636 	.endm
637 
638 	/*
639 	 * ldr_l - ldr <literal> pseudo-op with unlimited range
640 	 *
641 	 * @dst: destination register
642 	 * @sym: name of the symbol
643 	 * @cond: conditional opcode suffix
644 	 */
645 	.macro		ldr_l, dst:req, sym:req, cond
646 	__adldst_l	ldr, \dst, \sym, \dst, \cond
647 	.endm
648 
649 	/*
650 	 * str_l - str <literal> pseudo-op with unlimited range
651 	 *
652 	 * @src: source register
653 	 * @sym: name of the symbol
654 	 * @tmp: mandatory scratch register
655 	 * @cond: conditional opcode suffix
656 	 */
657 	.macro		str_l, src:req, sym:req, tmp:req, cond
658 	__adldst_l	str, \src, \sym, \tmp, \cond
659 	.endm
660 
661 	.macro		__ldst_va, op, reg, tmp, sym, cond, offset
662 #if __LINUX_ARM_ARCH__ >= 7 || \
663     !defined(CONFIG_ARM_HAS_GROUP_RELOCS) || \
664     (defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS))
665 	mov_l		\tmp, \sym, \cond
666 #else
667 	/*
668 	 * Avoid a literal load, by emitting a sequence of ADD/LDR instructions
669 	 * with the appropriate relocations. The combined sequence has a range
670 	 * of -/+ 256 MiB, which should be sufficient for the core kernel and
671 	 * for modules loaded into the module region.
672 	 */
673 	.globl		\sym
674 	.reloc		.L0_\@, R_ARM_ALU_PC_G0_NC, \sym
675 	.reloc		.L1_\@, R_ARM_ALU_PC_G1_NC, \sym
676 	.reloc		.L2_\@, R_ARM_LDR_PC_G2, \sym
677 .L0_\@: sub\cond	\tmp, pc, #8 - \offset
678 .L1_\@: sub\cond	\tmp, \tmp, #4 - \offset
679 .L2_\@:
680 #endif
681 	\op\cond	\reg, [\tmp, #\offset]
682 	.endm
683 
684 	/*
685 	 * ldr_va - load a 32-bit word from the virtual address of \sym
686 	 */
687 	.macro		ldr_va, rd:req, sym:req, cond, tmp, offset=0
688 	.ifnb		\tmp
689 	__ldst_va	ldr, \rd, \tmp, \sym, \cond, \offset
690 	.else
691 	__ldst_va	ldr, \rd, \rd, \sym, \cond, \offset
692 	.endif
693 	.endm
694 
695 	/*
696 	 * str_va - store a 32-bit word to the virtual address of \sym
697 	 */
698 	.macro		str_va, rn:req, sym:req, tmp:req, cond
699 	__ldst_va	str, \rn, \tmp, \sym, \cond, 0
700 	.endm
701 
702 	/*
703 	 * ldr_this_cpu_armv6 - Load a 32-bit word from the per-CPU variable 'sym',
704 	 *			without using a temp register. Supported in ARM mode
705 	 *			only.
706 	 */
707 	.macro		ldr_this_cpu_armv6, rd:req, sym:req
708 	this_cpu_offset	\rd
709 	.globl		\sym
710 	.reloc		.L0_\@, R_ARM_ALU_PC_G0_NC, \sym
711 	.reloc		.L1_\@, R_ARM_ALU_PC_G1_NC, \sym
712 	.reloc		.L2_\@, R_ARM_LDR_PC_G2, \sym
713 	add		\rd, \rd, pc
714 .L0_\@: sub		\rd, \rd, #4
715 .L1_\@: sub		\rd, \rd, #0
716 .L2_\@: ldr		\rd, [\rd, #4]
717 	.endm
718 
719 	/*
720 	 * ldr_this_cpu - Load a 32-bit word from the per-CPU variable 'sym'
721 	 *		  into register 'rd', which may be the stack pointer,
722 	 *		  using 't1' and 't2' as general temp registers. These
723 	 *		  are permitted to overlap with 'rd' if != sp
724 	 */
725 	.macro		ldr_this_cpu, rd:req, sym:req, t1:req, t2:req
726 #ifndef CONFIG_SMP
727 	ldr_va		\rd, \sym, tmp=\t1
728 #elif __LINUX_ARM_ARCH__ >= 7 || \
729       !defined(CONFIG_ARM_HAS_GROUP_RELOCS) || \
730       (defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS))
731 	this_cpu_offset	\t1
732 	mov_l		\t2, \sym
733 	ldr		\rd, [\t1, \t2]
734 #else
735 	ldr_this_cpu_armv6 \rd, \sym
736 #endif
737 	.endm
738 
739 	/*
740 	 * rev_l - byte-swap a 32-bit value
741 	 *
742 	 * @val: source/destination register
743 	 * @tmp: scratch register
744 	 */
745 	.macro		rev_l, val:req, tmp:req
746 	.if		__LINUX_ARM_ARCH__ < 6
747 	eor		\tmp, \val, \val, ror #16
748 	bic		\tmp, \tmp, #0x00ff0000
749 	mov		\val, \val, ror #8
750 	eor		\val, \val, \tmp, lsr #8
751 	.else
752 	rev		\val, \val
753 	.endif
754 	.endm
755 
756 	.if		__LINUX_ARM_ARCH__ < 6
757 	.set		.Lrev_l_uses_tmp, 1
758 	.else
759 	.set		.Lrev_l_uses_tmp, 0
760 	.endif
761 
762 	/*
763 	 * bl_r - branch and link to register
764 	 *
765 	 * @dst: target to branch to
766 	 * @c: conditional opcode suffix
767 	 */
768 	.macro		bl_r, dst:req, c
769 	.if		__LINUX_ARM_ARCH__ < 6
770 	mov\c		lr, pc
771 	mov\c		pc, \dst
772 	.else
773 	blx\c		\dst
774 	.endif
775 	.endm
776 
777 #endif /* __ASM_ASSEMBLER_H__ */
778