xref: /openbmc/linux/arch/arm64/include/asm/assembler.h (revision a9d85efb)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Based on arch/arm/include/asm/assembler.h, arch/arm/mm/proc-macros.S
4  *
5  * Copyright (C) 1996-2000 Russell King
6  * Copyright (C) 2012 ARM Ltd.
7  */
8 #ifndef __ASSEMBLY__
9 #error "Only include this from assembly code"
10 #endif
11 
12 #ifndef __ASM_ASSEMBLER_H
13 #define __ASM_ASSEMBLER_H
14 
15 #include <asm-generic/export.h>
16 
17 #include <asm/asm-offsets.h>
18 #include <asm/alternative.h>
19 #include <asm/asm-bug.h>
20 #include <asm/cpufeature.h>
21 #include <asm/cputype.h>
22 #include <asm/debug-monitors.h>
23 #include <asm/page.h>
24 #include <asm/pgtable-hwdef.h>
25 #include <asm/ptrace.h>
26 #include <asm/thread_info.h>
27 
28 	/*
29 	 * Provide a wxN alias for each wN register so what we can paste a xN
30 	 * reference after a 'w' to obtain the 32-bit version.
31 	 */
32 	.irp	n,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30
33 	wx\n	.req	w\n
34 	.endr
35 
36 	.macro save_and_disable_daif, flags
37 	mrs	\flags, daif
38 	msr	daifset, #0xf
39 	.endm
40 
41 	.macro disable_daif
42 	msr	daifset, #0xf
43 	.endm
44 
45 	.macro enable_daif
46 	msr	daifclr, #0xf
47 	.endm
48 
49 	.macro	restore_daif, flags:req
50 	msr	daif, \flags
51 	.endm
52 
53 	/* IRQ/FIQ are the lowest priority flags, unconditionally unmask the rest. */
54 	.macro enable_da
55 	msr	daifclr, #(8 | 4)
56 	.endm
57 
58 /*
59  * Save/restore interrupts.
60  */
61 	.macro	save_and_disable_irq, flags
62 	mrs	\flags, daif
63 	msr	daifset, #3
64 	.endm
65 
66 	.macro	restore_irq, flags
67 	msr	daif, \flags
68 	.endm
69 
70 	.macro	enable_dbg
71 	msr	daifclr, #8
72 	.endm
73 
74 	.macro	disable_step_tsk, flgs, tmp
75 	tbz	\flgs, #TIF_SINGLESTEP, 9990f
76 	mrs	\tmp, mdscr_el1
77 	bic	\tmp, \tmp, #DBG_MDSCR_SS
78 	msr	mdscr_el1, \tmp
79 	isb	// Synchronise with enable_dbg
80 9990:
81 	.endm
82 
83 	/* call with daif masked */
84 	.macro	enable_step_tsk, flgs, tmp
85 	tbz	\flgs, #TIF_SINGLESTEP, 9990f
86 	mrs	\tmp, mdscr_el1
87 	orr	\tmp, \tmp, #DBG_MDSCR_SS
88 	msr	mdscr_el1, \tmp
89 9990:
90 	.endm
91 
92 /*
93  * RAS Error Synchronization barrier
94  */
95 	.macro  esb
96 #ifdef CONFIG_ARM64_RAS_EXTN
97 	hint    #16
98 #else
99 	nop
100 #endif
101 	.endm
102 
103 /*
104  * Value prediction barrier
105  */
106 	.macro	csdb
107 	hint	#20
108 	.endm
109 
110 /*
111  * Speculation barrier
112  */
113 	.macro	sb
114 alternative_if_not ARM64_HAS_SB
115 	dsb	nsh
116 	isb
117 alternative_else
118 	SB_BARRIER_INSN
119 	nop
120 alternative_endif
121 	.endm
122 
123 /*
124  * NOP sequence
125  */
126 	.macro	nops, num
127 	.rept	\num
128 	nop
129 	.endr
130 	.endm
131 
132 /*
133  * Create an exception table entry for `insn`, which will branch to `fixup`
134  * when an unhandled fault is taken.
135  */
136 	.macro		_asm_extable, insn, fixup
137 	.pushsection	__ex_table, "a"
138 	.align		3
139 	.long		(\insn - .), (\fixup - .)
140 	.popsection
141 	.endm
142 
143 /*
144  * Create an exception table entry for `insn` if `fixup` is provided. Otherwise
145  * do nothing.
146  */
147 	.macro		_cond_extable, insn, fixup
148 	.ifnc		\fixup,
149 	_asm_extable	\insn, \fixup
150 	.endif
151 	.endm
152 
153 
154 #define USER(l, x...)				\
155 9999:	x;					\
156 	_asm_extable	9999b, l
157 
158 /*
159  * Register aliases.
160  */
161 lr	.req	x30		// link register
162 
163 /*
164  * Vector entry
165  */
166 	 .macro	ventry	label
167 	.align	7
168 	b	\label
169 	.endm
170 
171 /*
172  * Select code when configured for BE.
173  */
174 #ifdef CONFIG_CPU_BIG_ENDIAN
175 #define CPU_BE(code...) code
176 #else
177 #define CPU_BE(code...)
178 #endif
179 
180 /*
181  * Select code when configured for LE.
182  */
183 #ifdef CONFIG_CPU_BIG_ENDIAN
184 #define CPU_LE(code...)
185 #else
186 #define CPU_LE(code...) code
187 #endif
188 
189 /*
190  * Define a macro that constructs a 64-bit value by concatenating two
191  * 32-bit registers. Note that on big endian systems the order of the
192  * registers is swapped.
193  */
194 #ifndef CONFIG_CPU_BIG_ENDIAN
195 	.macro	regs_to_64, rd, lbits, hbits
196 #else
197 	.macro	regs_to_64, rd, hbits, lbits
198 #endif
199 	orr	\rd, \lbits, \hbits, lsl #32
200 	.endm
201 
202 /*
203  * Pseudo-ops for PC-relative adr/ldr/str <reg>, <symbol> where
204  * <symbol> is within the range +/- 4 GB of the PC.
205  */
206 	/*
207 	 * @dst: destination register (64 bit wide)
208 	 * @sym: name of the symbol
209 	 */
210 	.macro	adr_l, dst, sym
211 	adrp	\dst, \sym
212 	add	\dst, \dst, :lo12:\sym
213 	.endm
214 
215 	/*
216 	 * @dst: destination register (32 or 64 bit wide)
217 	 * @sym: name of the symbol
218 	 * @tmp: optional 64-bit scratch register to be used if <dst> is a
219 	 *       32-bit wide register, in which case it cannot be used to hold
220 	 *       the address
221 	 */
222 	.macro	ldr_l, dst, sym, tmp=
223 	.ifb	\tmp
224 	adrp	\dst, \sym
225 	ldr	\dst, [\dst, :lo12:\sym]
226 	.else
227 	adrp	\tmp, \sym
228 	ldr	\dst, [\tmp, :lo12:\sym]
229 	.endif
230 	.endm
231 
232 	/*
233 	 * @src: source register (32 or 64 bit wide)
234 	 * @sym: name of the symbol
235 	 * @tmp: mandatory 64-bit scratch register to calculate the address
236 	 *       while <src> needs to be preserved.
237 	 */
238 	.macro	str_l, src, sym, tmp
239 	adrp	\tmp, \sym
240 	str	\src, [\tmp, :lo12:\sym]
241 	.endm
242 
243 	/*
244 	 * @dst: destination register
245 	 */
246 #if defined(__KVM_NVHE_HYPERVISOR__) || defined(__KVM_VHE_HYPERVISOR__)
247 	.macro	get_this_cpu_offset, dst
248 	mrs	\dst, tpidr_el2
249 	.endm
250 #else
251 	.macro	get_this_cpu_offset, dst
252 alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
253 	mrs	\dst, tpidr_el1
254 alternative_else
255 	mrs	\dst, tpidr_el2
256 alternative_endif
257 	.endm
258 
259 	.macro	set_this_cpu_offset, src
260 alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
261 	msr	tpidr_el1, \src
262 alternative_else
263 	msr	tpidr_el2, \src
264 alternative_endif
265 	.endm
266 #endif
267 
268 	/*
269 	 * @dst: Result of per_cpu(sym, smp_processor_id()) (can be SP)
270 	 * @sym: The name of the per-cpu variable
271 	 * @tmp: scratch register
272 	 */
273 	.macro adr_this_cpu, dst, sym, tmp
274 	adrp	\tmp, \sym
275 	add	\dst, \tmp, #:lo12:\sym
276 	get_this_cpu_offset \tmp
277 	add	\dst, \dst, \tmp
278 	.endm
279 
280 	/*
281 	 * @dst: Result of READ_ONCE(per_cpu(sym, smp_processor_id()))
282 	 * @sym: The name of the per-cpu variable
283 	 * @tmp: scratch register
284 	 */
285 	.macro ldr_this_cpu dst, sym, tmp
286 	adr_l	\dst, \sym
287 	get_this_cpu_offset \tmp
288 	ldr	\dst, [\dst, \tmp]
289 	.endm
290 
291 /*
292  * vma_vm_mm - get mm pointer from vma pointer (vma->vm_mm)
293  */
294 	.macro	vma_vm_mm, rd, rn
295 	ldr	\rd, [\rn, #VMA_VM_MM]
296 	.endm
297 
298 /*
299  * read_ctr - read CTR_EL0. If the system has mismatched register fields,
300  * provide the system wide safe value from arm64_ftr_reg_ctrel0.sys_val
301  */
302 	.macro	read_ctr, reg
303 #ifndef __KVM_NVHE_HYPERVISOR__
304 alternative_if_not ARM64_MISMATCHED_CACHE_TYPE
305 	mrs	\reg, ctr_el0			// read CTR
306 	nop
307 alternative_else
308 	ldr_l	\reg, arm64_ftr_reg_ctrel0 + ARM64_FTR_SYSVAL
309 alternative_endif
310 #else
311 alternative_if_not ARM64_KVM_PROTECTED_MODE
312 	ASM_BUG()
313 alternative_else_nop_endif
314 alternative_cb kvm_compute_final_ctr_el0
315 	movz	\reg, #0
316 	movk	\reg, #0, lsl #16
317 	movk	\reg, #0, lsl #32
318 	movk	\reg, #0, lsl #48
319 alternative_cb_end
320 #endif
321 	.endm
322 
323 
324 /*
325  * raw_dcache_line_size - get the minimum D-cache line size on this CPU
326  * from the CTR register.
327  */
328 	.macro	raw_dcache_line_size, reg, tmp
329 	mrs	\tmp, ctr_el0			// read CTR
330 	ubfm	\tmp, \tmp, #16, #19		// cache line size encoding
331 	mov	\reg, #4			// bytes per word
332 	lsl	\reg, \reg, \tmp		// actual cache line size
333 	.endm
334 
335 /*
336  * dcache_line_size - get the safe D-cache line size across all CPUs
337  */
338 	.macro	dcache_line_size, reg, tmp
339 	read_ctr	\tmp
340 	ubfm		\tmp, \tmp, #16, #19	// cache line size encoding
341 	mov		\reg, #4		// bytes per word
342 	lsl		\reg, \reg, \tmp	// actual cache line size
343 	.endm
344 
345 /*
346  * raw_icache_line_size - get the minimum I-cache line size on this CPU
347  * from the CTR register.
348  */
349 	.macro	raw_icache_line_size, reg, tmp
350 	mrs	\tmp, ctr_el0			// read CTR
351 	and	\tmp, \tmp, #0xf		// cache line size encoding
352 	mov	\reg, #4			// bytes per word
353 	lsl	\reg, \reg, \tmp		// actual cache line size
354 	.endm
355 
356 /*
357  * icache_line_size - get the safe I-cache line size across all CPUs
358  */
359 	.macro	icache_line_size, reg, tmp
360 	read_ctr	\tmp
361 	and		\tmp, \tmp, #0xf	// cache line size encoding
362 	mov		\reg, #4		// bytes per word
363 	lsl		\reg, \reg, \tmp	// actual cache line size
364 	.endm
365 
366 /*
367  * tcr_set_t0sz - update TCR.T0SZ so that we can load the ID map
368  */
369 	.macro	tcr_set_t0sz, valreg, t0sz
370 	bfi	\valreg, \t0sz, #TCR_T0SZ_OFFSET, #TCR_TxSZ_WIDTH
371 	.endm
372 
373 /*
374  * tcr_set_t1sz - update TCR.T1SZ
375  */
376 	.macro	tcr_set_t1sz, valreg, t1sz
377 	bfi	\valreg, \t1sz, #TCR_T1SZ_OFFSET, #TCR_TxSZ_WIDTH
378 	.endm
379 
380 /*
381  * tcr_compute_pa_size - set TCR.(I)PS to the highest supported
382  * ID_AA64MMFR0_EL1.PARange value
383  *
384  *	tcr:		register with the TCR_ELx value to be updated
385  *	pos:		IPS or PS bitfield position
386  *	tmp{0,1}:	temporary registers
387  */
388 	.macro	tcr_compute_pa_size, tcr, pos, tmp0, tmp1
389 	mrs	\tmp0, ID_AA64MMFR0_EL1
390 	// Narrow PARange to fit the PS field in TCR_ELx
391 	ubfx	\tmp0, \tmp0, #ID_AA64MMFR0_PARANGE_SHIFT, #3
392 	mov	\tmp1, #ID_AA64MMFR0_PARANGE_MAX
393 	cmp	\tmp0, \tmp1
394 	csel	\tmp0, \tmp1, \tmp0, hi
395 	bfi	\tcr, \tmp0, \pos, #3
396 	.endm
397 
398 	.macro __dcache_op_workaround_clean_cache, op, addr
399 alternative_if_not ARM64_WORKAROUND_CLEAN_CACHE
400 	dc	\op, \addr
401 alternative_else
402 	dc	civac, \addr
403 alternative_endif
404 	.endm
405 
406 /*
407  * Macro to perform a data cache maintenance for the interval
408  * [start, end)
409  *
410  * 	op:		operation passed to dc instruction
411  * 	domain:		domain used in dsb instruciton
412  * 	start:          starting virtual address of the region
413  * 	end:            end virtual address of the region
414  * 	fixup:		optional label to branch to on user fault
415  * 	Corrupts:       start, end, tmp1, tmp2
416  */
417 	.macro dcache_by_line_op op, domain, start, end, tmp1, tmp2, fixup
418 	dcache_line_size \tmp1, \tmp2
419 	sub	\tmp2, \tmp1, #1
420 	bic	\start, \start, \tmp2
421 .Ldcache_op\@:
422 	.ifc	\op, cvau
423 	__dcache_op_workaround_clean_cache \op, \start
424 	.else
425 	.ifc	\op, cvac
426 	__dcache_op_workaround_clean_cache \op, \start
427 	.else
428 	.ifc	\op, cvap
429 	sys	3, c7, c12, 1, \start	// dc cvap
430 	.else
431 	.ifc	\op, cvadp
432 	sys	3, c7, c13, 1, \start	// dc cvadp
433 	.else
434 	dc	\op, \start
435 	.endif
436 	.endif
437 	.endif
438 	.endif
439 	add	\start, \start, \tmp1
440 	cmp	\start, \end
441 	b.lo	.Ldcache_op\@
442 	dsb	\domain
443 
444 	_cond_extable .Ldcache_op\@, \fixup
445 	.endm
446 
447 /*
448  * Macro to perform an instruction cache maintenance for the interval
449  * [start, end)
450  *
451  * 	start, end:	virtual addresses describing the region
452  *	fixup:		optional label to branch to on user fault
453  * 	Corrupts:	tmp1, tmp2
454  */
455 	.macro invalidate_icache_by_line start, end, tmp1, tmp2, fixup
456 	icache_line_size \tmp1, \tmp2
457 	sub	\tmp2, \tmp1, #1
458 	bic	\tmp2, \start, \tmp2
459 .Licache_op\@:
460 	ic	ivau, \tmp2			// invalidate I line PoU
461 	add	\tmp2, \tmp2, \tmp1
462 	cmp	\tmp2, \end
463 	b.lo	.Licache_op\@
464 	dsb	ish
465 	isb
466 
467 	_cond_extable .Licache_op\@, \fixup
468 	.endm
469 
470 /*
471  * reset_pmuserenr_el0 - reset PMUSERENR_EL0 if PMUv3 present
472  */
473 	.macro	reset_pmuserenr_el0, tmpreg
474 	mrs	\tmpreg, id_aa64dfr0_el1
475 	sbfx	\tmpreg, \tmpreg, #ID_AA64DFR0_PMUVER_SHIFT, #4
476 	cmp	\tmpreg, #1			// Skip if no PMU present
477 	b.lt	9000f
478 	msr	pmuserenr_el0, xzr		// Disable PMU access from EL0
479 9000:
480 	.endm
481 
482 /*
483  * reset_amuserenr_el0 - reset AMUSERENR_EL0 if AMUv1 present
484  */
485 	.macro	reset_amuserenr_el0, tmpreg
486 	mrs	\tmpreg, id_aa64pfr0_el1	// Check ID_AA64PFR0_EL1
487 	ubfx	\tmpreg, \tmpreg, #ID_AA64PFR0_AMU_SHIFT, #4
488 	cbz	\tmpreg, .Lskip_\@		// Skip if no AMU present
489 	msr_s	SYS_AMUSERENR_EL0, xzr		// Disable AMU access from EL0
490 .Lskip_\@:
491 	.endm
492 /*
493  * copy_page - copy src to dest using temp registers t1-t8
494  */
495 	.macro copy_page dest:req src:req t1:req t2:req t3:req t4:req t5:req t6:req t7:req t8:req
496 9998:	ldp	\t1, \t2, [\src]
497 	ldp	\t3, \t4, [\src, #16]
498 	ldp	\t5, \t6, [\src, #32]
499 	ldp	\t7, \t8, [\src, #48]
500 	add	\src, \src, #64
501 	stnp	\t1, \t2, [\dest]
502 	stnp	\t3, \t4, [\dest, #16]
503 	stnp	\t5, \t6, [\dest, #32]
504 	stnp	\t7, \t8, [\dest, #48]
505 	add	\dest, \dest, #64
506 	tst	\src, #(PAGE_SIZE - 1)
507 	b.ne	9998b
508 	.endm
509 
510 /*
511  * Annotate a function as being unsuitable for kprobes.
512  */
513 #ifdef CONFIG_KPROBES
514 #define NOKPROBE(x)				\
515 	.pushsection "_kprobe_blacklist", "aw";	\
516 	.quad	x;				\
517 	.popsection;
518 #else
519 #define NOKPROBE(x)
520 #endif
521 
522 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
523 #define EXPORT_SYMBOL_NOKASAN(name)
524 #else
525 #define EXPORT_SYMBOL_NOKASAN(name)	EXPORT_SYMBOL(name)
526 #endif
527 
528 #ifdef CONFIG_KASAN_HW_TAGS
529 #define EXPORT_SYMBOL_NOHWKASAN(name)
530 #else
531 #define EXPORT_SYMBOL_NOHWKASAN(name)	EXPORT_SYMBOL_NOKASAN(name)
532 #endif
533 	/*
534 	 * Emit a 64-bit absolute little endian symbol reference in a way that
535 	 * ensures that it will be resolved at build time, even when building a
536 	 * PIE binary. This requires cooperation from the linker script, which
537 	 * must emit the lo32/hi32 halves individually.
538 	 */
539 	.macro	le64sym, sym
540 	.long	\sym\()_lo32
541 	.long	\sym\()_hi32
542 	.endm
543 
544 	/*
545 	 * mov_q - move an immediate constant into a 64-bit register using
546 	 *         between 2 and 4 movz/movk instructions (depending on the
547 	 *         magnitude and sign of the operand)
548 	 */
549 	.macro	mov_q, reg, val
550 	.if (((\val) >> 31) == 0 || ((\val) >> 31) == 0x1ffffffff)
551 	movz	\reg, :abs_g1_s:\val
552 	.else
553 	.if (((\val) >> 47) == 0 || ((\val) >> 47) == 0x1ffff)
554 	movz	\reg, :abs_g2_s:\val
555 	.else
556 	movz	\reg, :abs_g3:\val
557 	movk	\reg, :abs_g2_nc:\val
558 	.endif
559 	movk	\reg, :abs_g1_nc:\val
560 	.endif
561 	movk	\reg, :abs_g0_nc:\val
562 	.endm
563 
564 /*
565  * Return the current task_struct.
566  */
567 	.macro	get_current_task, rd
568 	mrs	\rd, sp_el0
569 	.endm
570 
571 /*
572  * Offset ttbr1 to allow for 48-bit kernel VAs set with 52-bit PTRS_PER_PGD.
573  * orr is used as it can cover the immediate value (and is idempotent).
574  * In future this may be nop'ed out when dealing with 52-bit kernel VAs.
575  * 	ttbr: Value of ttbr to set, modified.
576  */
577 	.macro	offset_ttbr1, ttbr, tmp
578 #ifdef CONFIG_ARM64_VA_BITS_52
579 	mrs_s	\tmp, SYS_ID_AA64MMFR2_EL1
580 	and	\tmp, \tmp, #(0xf << ID_AA64MMFR2_LVA_SHIFT)
581 	cbnz	\tmp, .Lskipoffs_\@
582 	orr	\ttbr, \ttbr, #TTBR1_BADDR_4852_OFFSET
583 .Lskipoffs_\@ :
584 #endif
585 	.endm
586 
587 /*
588  * Perform the reverse of offset_ttbr1.
589  * bic is used as it can cover the immediate value and, in future, won't need
590  * to be nop'ed out when dealing with 52-bit kernel VAs.
591  */
592 	.macro	restore_ttbr1, ttbr
593 #ifdef CONFIG_ARM64_VA_BITS_52
594 	bic	\ttbr, \ttbr, #TTBR1_BADDR_4852_OFFSET
595 #endif
596 	.endm
597 
598 /*
599  * Arrange a physical address in a TTBR register, taking care of 52-bit
600  * addresses.
601  *
602  * 	phys:	physical address, preserved
603  * 	ttbr:	returns the TTBR value
604  */
605 	.macro	phys_to_ttbr, ttbr, phys
606 #ifdef CONFIG_ARM64_PA_BITS_52
607 	orr	\ttbr, \phys, \phys, lsr #46
608 	and	\ttbr, \ttbr, #TTBR_BADDR_MASK_52
609 #else
610 	mov	\ttbr, \phys
611 #endif
612 	.endm
613 
614 	.macro	phys_to_pte, pte, phys
615 #ifdef CONFIG_ARM64_PA_BITS_52
616 	/*
617 	 * We assume \phys is 64K aligned and this is guaranteed by only
618 	 * supporting this configuration with 64K pages.
619 	 */
620 	orr	\pte, \phys, \phys, lsr #36
621 	and	\pte, \pte, #PTE_ADDR_MASK
622 #else
623 	mov	\pte, \phys
624 #endif
625 	.endm
626 
627 	.macro	pte_to_phys, phys, pte
628 #ifdef CONFIG_ARM64_PA_BITS_52
629 	ubfiz	\phys, \pte, #(48 - 16 - 12), #16
630 	bfxil	\phys, \pte, #16, #32
631 	lsl	\phys, \phys, #16
632 #else
633 	and	\phys, \pte, #PTE_ADDR_MASK
634 #endif
635 	.endm
636 
637 /*
638  * tcr_clear_errata_bits - Clear TCR bits that trigger an errata on this CPU.
639  */
640 	.macro	tcr_clear_errata_bits, tcr, tmp1, tmp2
641 #ifdef CONFIG_FUJITSU_ERRATUM_010001
642 	mrs	\tmp1, midr_el1
643 
644 	mov_q	\tmp2, MIDR_FUJITSU_ERRATUM_010001_MASK
645 	and	\tmp1, \tmp1, \tmp2
646 	mov_q	\tmp2, MIDR_FUJITSU_ERRATUM_010001
647 	cmp	\tmp1, \tmp2
648 	b.ne	10f
649 
650 	mov_q	\tmp2, TCR_CLEAR_FUJITSU_ERRATUM_010001
651 	bic	\tcr, \tcr, \tmp2
652 10:
653 #endif /* CONFIG_FUJITSU_ERRATUM_010001 */
654 	.endm
655 
656 /**
657  * Errata workaround prior to disable MMU. Insert an ISB immediately prior
658  * to executing the MSR that will change SCTLR_ELn[M] from a value of 1 to 0.
659  */
660 	.macro pre_disable_mmu_workaround
661 #ifdef CONFIG_QCOM_FALKOR_ERRATUM_E1041
662 	isb
663 #endif
664 	.endm
665 
666 	/*
667 	 * frame_push - Push @regcount callee saved registers to the stack,
668 	 *              starting at x19, as well as x29/x30, and set x29 to
669 	 *              the new value of sp. Add @extra bytes of stack space
670 	 *              for locals.
671 	 */
672 	.macro		frame_push, regcount:req, extra
673 	__frame		st, \regcount, \extra
674 	.endm
675 
676 	/*
677 	 * frame_pop  - Pop the callee saved registers from the stack that were
678 	 *              pushed in the most recent call to frame_push, as well
679 	 *              as x29/x30 and any extra stack space that may have been
680 	 *              allocated.
681 	 */
682 	.macro		frame_pop
683 	__frame		ld
684 	.endm
685 
686 	.macro		__frame_regs, reg1, reg2, op, num
687 	.if		.Lframe_regcount == \num
688 	\op\()r		\reg1, [sp, #(\num + 1) * 8]
689 	.elseif		.Lframe_regcount > \num
690 	\op\()p		\reg1, \reg2, [sp, #(\num + 1) * 8]
691 	.endif
692 	.endm
693 
694 	.macro		__frame, op, regcount, extra=0
695 	.ifc		\op, st
696 	.if		(\regcount) < 0 || (\regcount) > 10
697 	.error		"regcount should be in the range [0 ... 10]"
698 	.endif
699 	.if		((\extra) % 16) != 0
700 	.error		"extra should be a multiple of 16 bytes"
701 	.endif
702 	.ifdef		.Lframe_regcount
703 	.if		.Lframe_regcount != -1
704 	.error		"frame_push/frame_pop may not be nested"
705 	.endif
706 	.endif
707 	.set		.Lframe_regcount, \regcount
708 	.set		.Lframe_extra, \extra
709 	.set		.Lframe_local_offset, ((\regcount + 3) / 2) * 16
710 	stp		x29, x30, [sp, #-.Lframe_local_offset - .Lframe_extra]!
711 	mov		x29, sp
712 	.endif
713 
714 	__frame_regs	x19, x20, \op, 1
715 	__frame_regs	x21, x22, \op, 3
716 	__frame_regs	x23, x24, \op, 5
717 	__frame_regs	x25, x26, \op, 7
718 	__frame_regs	x27, x28, \op, 9
719 
720 	.ifc		\op, ld
721 	.if		.Lframe_regcount == -1
722 	.error		"frame_push/frame_pop may not be nested"
723 	.endif
724 	ldp		x29, x30, [sp], #.Lframe_local_offset + .Lframe_extra
725 	.set		.Lframe_regcount, -1
726 	.endif
727 	.endm
728 
729 /*
730  * Set SCTLR_ELx to the @reg value, and invalidate the local icache
731  * in the process. This is called when setting the MMU on.
732  */
733 .macro set_sctlr, sreg, reg
734 	msr	\sreg, \reg
735 	isb
736 	/*
737 	 * Invalidate the local I-cache so that any instructions fetched
738 	 * speculatively from the PoC are discarded, since they may have
739 	 * been dynamically patched at the PoU.
740 	 */
741 	ic	iallu
742 	dsb	nsh
743 	isb
744 .endm
745 
746 .macro set_sctlr_el1, reg
747 	set_sctlr sctlr_el1, \reg
748 .endm
749 
750 .macro set_sctlr_el2, reg
751 	set_sctlr sctlr_el2, \reg
752 .endm
753 
754 	/*
755 	 * Check whether preempt/bh-disabled asm code should yield as soon as
756 	 * it is able. This is the case if we are currently running in task
757 	 * context, and either a softirq is pending, or the TIF_NEED_RESCHED
758 	 * flag is set and re-enabling preemption a single time would result in
759 	 * a preempt count of zero. (Note that the TIF_NEED_RESCHED flag is
760 	 * stored negated in the top word of the thread_info::preempt_count
761 	 * field)
762 	 */
763 	.macro		cond_yield, lbl:req, tmp:req, tmp2:req
764 	get_current_task \tmp
765 	ldr		\tmp, [\tmp, #TSK_TI_PREEMPT]
766 	/*
767 	 * If we are serving a softirq, there is no point in yielding: the
768 	 * softirq will not be preempted no matter what we do, so we should
769 	 * run to completion as quickly as we can.
770 	 */
771 	tbnz		\tmp, #SOFTIRQ_SHIFT, .Lnoyield_\@
772 #ifdef CONFIG_PREEMPTION
773 	sub		\tmp, \tmp, #PREEMPT_DISABLE_OFFSET
774 	cbz		\tmp, \lbl
775 #endif
776 	adr_l		\tmp, irq_stat + IRQ_CPUSTAT_SOFTIRQ_PENDING
777 	get_this_cpu_offset	\tmp2
778 	ldr		w\tmp, [\tmp, \tmp2]
779 	cbnz		w\tmp, \lbl	// yield on pending softirq in task context
780 .Lnoyield_\@:
781 	.endm
782 
783 /*
784  * This macro emits a program property note section identifying
785  * architecture features which require special handling, mainly for
786  * use in assembly files included in the VDSO.
787  */
788 
789 #define NT_GNU_PROPERTY_TYPE_0  5
790 #define GNU_PROPERTY_AARCH64_FEATURE_1_AND      0xc0000000
791 
792 #define GNU_PROPERTY_AARCH64_FEATURE_1_BTI      (1U << 0)
793 #define GNU_PROPERTY_AARCH64_FEATURE_1_PAC      (1U << 1)
794 
795 #ifdef CONFIG_ARM64_BTI_KERNEL
796 #define GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT		\
797 		((GNU_PROPERTY_AARCH64_FEATURE_1_BTI |	\
798 		  GNU_PROPERTY_AARCH64_FEATURE_1_PAC))
799 #endif
800 
801 #ifdef GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT
802 .macro emit_aarch64_feature_1_and, feat=GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT
803 	.pushsection .note.gnu.property, "a"
804 	.align  3
805 	.long   2f - 1f
806 	.long   6f - 3f
807 	.long   NT_GNU_PROPERTY_TYPE_0
808 1:      .string "GNU"
809 2:
810 	.align  3
811 3:      .long   GNU_PROPERTY_AARCH64_FEATURE_1_AND
812 	.long   5f - 4f
813 4:
814 	/*
815 	 * This is described with an array of char in the Linux API
816 	 * spec but the text and all other usage (including binutils,
817 	 * clang and GCC) treat this as a 32 bit value so no swizzling
818 	 * is required for big endian.
819 	 */
820 	.long   \feat
821 5:
822 	.align  3
823 6:
824 	.popsection
825 .endm
826 
827 #else
828 .macro emit_aarch64_feature_1_and, feat=0
829 .endm
830 
831 #endif /* GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT */
832 
833 #endif	/* __ASM_ASSEMBLER_H */
834