xref: /openbmc/linux/arch/alpha/lib/callback_srm.S (revision 22b6e7f3) 
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 *	arch/alpha/lib/callback_srm.S
4 */
5
6#include <linux/export.h>
7#include <asm/console.h>
8
9.text
10#define HWRPB_CRB_OFFSET 0xc0
11
12#if defined(CONFIG_ALPHA_SRM) || defined(CONFIG_ALPHA_GENERIC)
13.align 4
14srm_dispatch:
15#if defined(CONFIG_ALPHA_GENERIC)
16	ldl	$4,alpha_using_srm
17	beq	$4,nosrm
18#endif
19	ldq	$0,hwrpb	# gp is set up by CALLBACK macro.
20	ldl	$25,0($25)	# Pick up the wrapper data.
21	mov	$20,$21		# Shift arguments right.
22	mov	$19,$20
23	ldq	$1,HWRPB_CRB_OFFSET($0)
24	mov	$18,$19
25	mov	$17,$18
26	mov	$16,$17
27	addq	$0,$1,$2	# CRB address
28	ldq	$27,0($2)	# DISPATCH procedure descriptor (VMS call std)
29	extwl	$25,0,$16	# SRM callback function code
30	ldq	$3,8($27)	# call address
31	extwl	$25,2,$25	# argument information (VMS calling std)
32	jmp	($3)		# Return directly to caller of wrapper.
33
34.align 4
35.globl	srm_fixup
36.ent	srm_fixup
37srm_fixup:
38	ldgp	$29,0($27)
39#if defined(CONFIG_ALPHA_GENERIC)
40	ldl	$4,alpha_using_srm
41	beq	$4,nosrm
42#endif
43	ldq	$0,hwrpb
44	ldq	$1,HWRPB_CRB_OFFSET($0)
45	addq	$0,$1,$2	# CRB address
46	ldq	$27,16($2)	# VA of FIXUP procedure descriptor
47	ldq	$3,8($27)	# call address
48	lda	$25,2($31)	# two integer arguments
49	jmp	($3)		# Return directly to caller of srm_fixup.
50.end    srm_fixup
51
52#if defined(CONFIG_ALPHA_GENERIC)
53.align 3
54nosrm:
55	lda	$0,-1($31)
56	ret
57#endif
58
59#define CALLBACK(NAME, CODE, ARG_CNT) \
60.align 4; .globl callback_##NAME; .ent callback_##NAME; callback_##NAME##: \
61ldgp $29,0($27); br $25,srm_dispatch; .word CODE, ARG_CNT; .end callback_##NAME
62
63#else /* defined(CONFIG_ALPHA_SRM) || defined(CONFIG_ALPHA_GENERIC) */
64
65#define CALLBACK(NAME, CODE, ARG_CNT) \
66.align 3; .globl callback_##NAME; .ent callback_##NAME; callback_##NAME##: \
67lda $0,-1($31); ret; .end callback_##NAME
68
69.align 3
70.globl	srm_fixup
71.ent	srm_fixup
72srm_fixup:
73	lda	$0,-1($31)
74	ret
75.end	srm_fixup
76#endif /* defined(CONFIG_ALPHA_SRM) || defined(CONFIG_ALPHA_GENERIC) */
77
78CALLBACK(puts, CCB_PUTS, 4)
79CALLBACK(open, CCB_OPEN, 3)
80CALLBACK(close, CCB_CLOSE, 2)
81CALLBACK(read, CCB_READ, 5)
82CALLBACK(open_console, CCB_OPEN_CONSOLE, 1)
83CALLBACK(close_console, CCB_CLOSE_CONSOLE, 1)
84CALLBACK(getenv, CCB_GET_ENV, 4)
85CALLBACK(setenv, CCB_SET_ENV, 4)
86CALLBACK(getc, CCB_GETC, 2)
87CALLBACK(reset_term, CCB_RESET_TERM, 2)
88CALLBACK(term_int, CCB_SET_TERM_INT, 3)
89CALLBACK(term_ctl, CCB_SET_TERM_CTL, 3)
90CALLBACK(process_keycode, CCB_PROCESS_KEYCODE, 3)
91CALLBACK(ioctl, CCB_IOCTL, 6)
92CALLBACK(write, CCB_WRITE, 5)
93CALLBACK(reset_env, CCB_RESET_ENV, 4)
94CALLBACK(save_env, CCB_SAVE_ENV, 1)
95CALLBACK(pswitch, CCB_PSWITCH, 3)
96CALLBACK(bios_emul, CCB_BIOS_EMUL, 5)
97
98EXPORT_SYMBOL(callback_getenv)
99EXPORT_SYMBOL(callback_setenv)
100EXPORT_SYMBOL(callback_save_env)
101
102.data
103__alpha_using_srm:		# For use by bootpheader
104	.long 7			# value is not 1 for link debugging
105	.weak alpha_using_srm; alpha_using_srm = __alpha_using_srm
106__callback_init_done:		# For use by bootpheader
107	.long 7			# value is not 1 for link debugging
108	.weak callback_init_done; callback_init_done = __callback_init_done
109
110