1/*
2 * arch/alpha/kernel/head.S
3 *
4 * initial boot stuff.. At this point, the bootloader has already
5 * switched into OSF/1 PAL-code, and loaded us at the correct address
6 * (START_ADDR).  So there isn't much left for us to do: just set up
7 * the kernel global pointer and jump to the kernel entry-point.
8 */
9
10#include <linux/init.h>
11#include <asm/system.h>
12#include <asm/asm-offsets.h>
13
14__HEAD
15.globl swapper_pg_dir
16.globl _stext
17swapper_pg_dir=SWAPPER_PGD
18
19	.set noreorder
20	.globl	__start
21	.ent	__start
22_stext:
23__start:
24	.prologue 0
25	br	$27,1f
261:	ldgp	$29,0($27)
27	/* We need to get current_task_info loaded up...  */
28	lda	$8,init_thread_union
29	/* ... and find our stack ... */
30	lda	$30,0x4000 - SIZEOF_PT_REGS($8)
31	/* ... and then we can start the kernel.  */
32	jsr	$26,start_kernel
33	call_pal PAL_halt
34	.end __start
35
36#ifdef CONFIG_SMP
37	.align 3
38	.globl	__smp_callin
39	.ent	__smp_callin
40	/* On entry here from SRM console, the HWPCB of the per-cpu
41	   slot for this processor has been loaded.  We've arranged
42	   for the UNIQUE value for this process to contain the PCBB
43	   of the target idle task.  */
44__smp_callin:
45	.prologue 1
46	ldgp	$29,0($27)	# First order of business, load the GP.
47
48	call_pal PAL_rduniq	# Grab the target PCBB.
49	mov	$0,$16		# Install it.
50	call_pal PAL_swpctx
51
52	lda	$8,0x3fff	# Find "current".
53	bic	$30,$8,$8
54
55	jsr	$26,smp_callin
56	call_pal PAL_halt
57	.end __smp_callin
58#endif /* CONFIG_SMP */
59
60	#
61	# The following two functions are needed for supporting SRM PALcode
62	# on the PC164 (at least), since that PALcode manages the interrupt
63	# masking, and we cannot duplicate the effort without causing problems
64	#
65
66	.align 3
67	.globl	cserve_ena
68	.ent	cserve_ena
69cserve_ena:
70	.prologue 0
71	bis	$16,$16,$17
72	lda	$16,52($31)
73	call_pal PAL_cserve
74	ret	($26)
75	.end	cserve_ena
76
77	.align 3
78	.globl	cserve_dis
79	.ent	cserve_dis
80cserve_dis:
81	.prologue 0
82	bis	$16,$16,$17
83	lda	$16,53($31)
84	call_pal PAL_cserve
85	ret	($26)
86	.end	cserve_dis
87
88	#
89	# It is handy, on occasion, to make halt actually just loop.
90	# Putting it here means we dont have to recompile the whole
91	# kernel.
92	#
93
94	.align 3
95	.globl	halt
96	.ent	halt
97halt:
98	.prologue 0
99	call_pal PAL_halt
100	.end	halt
101