alpha/kernel/entry.S

1 /* SPDX-License-Identifier: GPL-2.0 */
5  * Kernel entry-points.
8 #include <asm/asm-offsets.h>
26 	.cfi_rel_offset	64, 8
35 	.size	\func, . - \func
39  * This defines the normal kernel pt-regs layout.
41  * regs 9-15 preserved by C code
42  * regs 16-18 saved by PAL-code
43  * regs 29-30 saved and set up by PAL-code
44  * JRP - Save regs 16-18 in a special area of the stack, so that
45  * the palcode-provided values are available to the signal handler.
52 	stq	$1, 8($sp)
58 	.cfi_rel_offset $1, 8
67 	stq	$8, 64($sp)
85 	.cfi_rel_offset	$8, 64
100 	ldq	$1, 8($sp)
110 	ldq	$8, 64($sp)
127 	.cfi_restore	$1
134 	.cfi_restore	$8
145 	.cfi_adjust_cfa_offset	-SP_OFF
149 	bsr	$1, do_switch_stack
152 	.cfi_rel_offset	$10, 8
161 	bsr	$1, undo_switch_stack
169 	.cfi_adjust_cfa_offset	-SWITCH_STACK_SIZE
173  * Non-syscall kernel entry points.
178 	lda	$8, 0x3fff
180 	bic	$sp, $8, $8
187 	lda	$8, 0x3fff
189 	bic	$sp, $8, $8
196 /* save $9 - $15 so the inline exception code can manipulate them.  */
200 	stq	$10, 8($sp)
207 	.cfi_rel_offset	$10, 8
215 	lda	$8, 0x3fff
216 	bic	$sp, $8, $8
220 	ldq	$10, 8($sp)
234 	.cfi_adjust_cfa_offset	-64
241 	lda	$8, 0x3fff
243 	bic	$sp, $8, $8
249 	lda	$sp, -256($sp)
255 	stq	$1, 8($sp)
258 	and	$0, 8, $0		/* user mode? */
260 	bne	$0, entUnaUser	/* yup -> do user-level unaligned fault */
264 	stq	$8, 64($sp)
272 	/* 16-18 PAL-saved */
285 	.cfi_rel_offset	$1, 1*8
286 	.cfi_rel_offset	$2, 2*8
287 	.cfi_rel_offset	$3, 3*8
288 	.cfi_rel_offset	$4, 4*8
289 	.cfi_rel_offset	$5, 5*8
290 	.cfi_rel_offset	$6, 6*8
291 	.cfi_rel_offset	$7, 7*8
292 	.cfi_rel_offset	$8, 8*8
293 	.cfi_rel_offset	$9, 9*8
294 	.cfi_rel_offset	$10, 10*8
295 	.cfi_rel_offset	$11, 11*8
296 	.cfi_rel_offset	$12, 12*8
297 	.cfi_rel_offset	$13, 13*8
298 	.cfi_rel_offset	$14, 14*8
299 	.cfi_rel_offset	$15, 15*8
300 	.cfi_rel_offset	$19, 19*8
301 	.cfi_rel_offset	$20, 20*8
302 	.cfi_rel_offset	$21, 21*8
303 	.cfi_rel_offset	$22, 22*8
304 	.cfi_rel_offset	$23, 23*8
305 	.cfi_rel_offset	$24, 24*8
306 	.cfi_rel_offset	$25, 25*8
307 	.cfi_rel_offset	$26, 26*8
308 	.cfi_rel_offset	$27, 27*8
309 	.cfi_rel_offset	$28, 28*8
310 	.cfi_rel_offset	$29, 29*8
311 	lda	$8, 0x3fff
313 	bic	$sp, $8, $8
316 	ldq	$1, 8($sp)
323 	ldq	$8, 64($sp)
331 	/* 16-18 PAL-saved */
344 	.cfi_restore	$1
351 	.cfi_restore	$8
370 	.cfi_adjust_cfa_offset	-256
379 	.cfi_adjust_cfa_offset	-256
381 	lda	$sp, -64($sp)
384 	stq	$10, 8($sp)
391 	.cfi_rel_offset	$10, 8
397 	lda	$8, 0x3fff
399 	bic	$sp, $8, $8
402 	ldq	$10, 8($sp)
416 	.cfi_adjust_cfa_offset	-64
422 	lda	$8, 0x3fff
424 	bic	$sp, $8, $8
437  * Note that a0-a2 are not saved by PALcode as with the other entry points.
446 	.cfi_rel_offset	64, 8
450 	lda	$8, 0x3fff
451 	bic	$sp, $8, $8
457 	ldl	$3, TI_FLAGS($8)
471 	beq	$4, 1f
473 1:	jsr	$26, ($27), sys_ni_syscall
478 	stq	$31, 72($sp)		/* a3=0 => no error */
483 	cmovne	$26, 0, $18		/* $18 = 0 => non-restartable */
485 	and	$0, 8, $0
492 	ldl	$17, TI_FLAGS($8)
496 	ldl	$2, TI_STATUS($8)
524 	addq	$31, 1, $1	/* set a3 for errno return */
527 	stq	$1, 72($sp)	/* a3 for return */
534  *       $8: current.
550 	 * or got through work_notifysig already.  Either case means no syscall
573 	ldl	$1, TI_STATUS($8)
574 	and	$1, TS_SAVED_FP, $3
575 	or	$1, TS_SAVED_FP, $2
576 	bne	$3, 1f
577 	stl	$2, TI_STATUS($8)
579 1:
593 	lda	$1, NR_syscalls($31)
596 	cmpult	$0, $1, $1
598 	beq	$1, 1f
600 1:	jsr	$26, ($27), sys_gettimeofday
607 	stq	$31, 72($sp)		/* a3=0 => no error */
622 	addq	$31, 1, $1	/* set a3 for errno return */
624 	stq	$1, 72($sp)	/* a3 for return */
639  * Save and restore the switch stack -- aka the balance of the user context.
647 	.cfi_register 64, $1
649 	lda	$sp, -SWITCH_STACK_SIZE($sp)
652 	stq	$10, 8($sp)
659 	ret	$31, ($1), 1
661 	.size	do_switch_stack, .-do_switch_stack
667 	.cfi_register 64, $1
670 	ldq	$10, 8($sp)
678 	ret	$31, ($1), 1
680 	.size	undo_switch_stack, .-undo_switch_stack
682 #define FR(n) n * 8 + TI_FP($8)
687 #define V(n) stt	$f##n, FR(n)  macro
688 	V( 0); V( 1); V( 2); V( 3)
689 	V( 4); V( 5); V( 6); V( 7)
690 	V( 8); V( 9); V(10); V(11)
691 	V(12); V(13); V(14); V(15)
692 	V(16); V(17); V(18); V(19)
693 	V(20); V(21); V(22); V(23)
694 	V(24); V(25); V(26); V(27)
696 	V(28); V(29); V(30)
700 #undef V
701 	.size	__save_fpu, .-__save_fpu
707 	beq	$3, 1f
708 #define V(n) ldt	$f##n, FR(n)  macro
710 	V( 0); V( 1); V( 2); V( 3)
712 	V( 4); V( 5); V( 6); V( 7)
713 	V( 8); V( 9); V(10); V(11)
714 	V(12); V(13); V(14); V(15)
715 	V(16); V(17); V(18); V(19)
716 	V(20); V(21); V(22); V(23)
717 	V(24); V(25); V(26); V(27)
718 	V(28); V(29); V(30)
719 1:	stl $2, TI_STATUS($8)
721 #undef V
733 	ldl	$1, TI_STATUS($8)
734 	and	$1, TS_RESTORE_FP, $3
735 	bne	$3, 1f
736 	or	$1, TS_RESTORE_FP | TS_SAVED_FP, $2
737 	and	$1, TS_SAVED_FP, $3
738 	stl	$2, TI_STATUS($8)
739 	bne	$3, 1f
741 1:
743 	lda	$8, 0x3fff
745 	bic	$sp, $8, $8
749 	.size	alpha_switch_to, .-alpha_switch_to
765  * ... and new kernel threads - here
791 	bsr	$1, do_switch_stack
793 	ldl	$1, TI_STATUS($8)
794 	and	$1, TS_SAVED_FP, $3
795 	or	$1, TS_SAVED_FP, $2
796 	bne	$3, 1f
797 	stl	$2, TI_STATUS($8)
799 1:
819 	lda	$sp, -SWITCH_STACK_SIZE($sp)
821 	bne	$9, 1f
823 1:	br	$1, undo_switch_stack
841 	   Store a non-zero there - -ENOSYS we need in register
844 	lda	$0, -ENOSYS