1 files changed, 109 insertions, 0 deletions
diff --git a/arch/alpha/lib/callback_srm.S b/arch/alpha/lib/callback_srm.S
new file mode 100644
index 0000000000..36b63f2951
--- /dev/null
+++ b/arch/alpha/lib/callback_srm.S
@@ -0,0 +1,109 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ *	arch/alpha/lib/callback_srm.S
+ */
+
+#include <linux/export.h>
+#include <asm/console.h>
+
+.text
+#define HWRPB_CRB_OFFSET 0xc0
+
+#if defined(CONFIG_ALPHA_SRM) || defined(CONFIG_ALPHA_GENERIC)
+.align 4
+srm_dispatch:
+#if defined(CONFIG_ALPHA_GENERIC)
+	ldl	$4,alpha_using_srm
+	beq	$4,nosrm
+#endif
+	ldq	$0,hwrpb	# gp is set up by CALLBACK macro.
+	ldl	$25,0($25)	# Pick up the wrapper data.
+	mov	$20,$21		# Shift arguments right.
+	mov	$19,$20
+	ldq	$1,HWRPB_CRB_OFFSET($0)
+	mov	$18,$19
+	mov	$17,$18
+	mov	$16,$17
+	addq	$0,$1,$2	# CRB address
+	ldq	$27,0($2)	# DISPATCH procedure descriptor (VMS call std)
+	extwl	$25,0,$16	# SRM callback function code
+	ldq	$3,8($27)	# call address
+	extwl	$25,2,$25	# argument information (VMS calling std)
+	jmp	($3)		# Return directly to caller of wrapper.
+
+.align 4
+.globl	srm_fixup
+.ent	srm_fixup
+srm_fixup:
+	ldgp	$29,0($27)
+#if defined(CONFIG_ALPHA_GENERIC)
+	ldl	$4,alpha_using_srm
+	beq	$4,nosrm
+#endif
+	ldq	$0,hwrpb
+	ldq	$1,HWRPB_CRB_OFFSET($0)
+	addq	$0,$1,$2	# CRB address
+	ldq	$27,16($2)	# VA of FIXUP procedure descriptor
+	ldq	$3,8($27)	# call address
+	lda	$25,2($31)	# two integer arguments
+	jmp	($3)		# Return directly to caller of srm_fixup.
+.end    srm_fixup
+
+#if defined(CONFIG_ALPHA_GENERIC)
+.align 3
+nosrm:
+	lda	$0,-1($31)
+	ret
+#endif
+
+#define CALLBACK(NAME, CODE, ARG_CNT) \
+.align 4; .globl callback_##NAME; .ent callback_##NAME; callback_##NAME##: \
+ldgp $29,0($27); br $25,srm_dispatch; .word CODE, ARG_CNT; .end callback_##NAME
+
+#else /* defined(CONFIG_ALPHA_SRM) || defined(CONFIG_ALPHA_GENERIC) */
+
+#define CALLBACK(NAME, CODE, ARG_CNT) \
+.align 3; .globl callback_##NAME; .ent callback_##NAME; callback_##NAME##: \
+lda $0,-1($31); ret; .end callback_##NAME
+
+.align 3
+.globl	srm_fixup
+.ent	srm_fixup
+srm_fixup:
+	lda	$0,-1($31)
+	ret
+.end	srm_fixup
+#endif /* defined(CONFIG_ALPHA_SRM) || defined(CONFIG_ALPHA_GENERIC) */
+
+CALLBACK(puts, CCB_PUTS, 4)
+CALLBACK(open, CCB_OPEN, 3)
+CALLBACK(close, CCB_CLOSE, 2)
+CALLBACK(read, CCB_READ, 5)
+CALLBACK(open_console, CCB_OPEN_CONSOLE, 1)
+CALLBACK(close_console, CCB_CLOSE_CONSOLE, 1)
+CALLBACK(getenv, CCB_GET_ENV, 4)
+CALLBACK(setenv, CCB_SET_ENV, 4)
+CALLBACK(getc, CCB_GETC, 2)
+CALLBACK(reset_term, CCB_RESET_TERM, 2)
+CALLBACK(term_int, CCB_SET_TERM_INT, 3)
+CALLBACK(term_ctl, CCB_SET_TERM_CTL, 3)
+CALLBACK(process_keycode, CCB_PROCESS_KEYCODE, 3)
+CALLBACK(ioctl, CCB_IOCTL, 6)
+CALLBACK(write, CCB_WRITE, 5)
+CALLBACK(reset_env, CCB_RESET_ENV, 4)
+CALLBACK(save_env, CCB_SAVE_ENV, 1)
+CALLBACK(pswitch, CCB_PSWITCH, 3)
+CALLBACK(bios_emul, CCB_BIOS_EMUL, 5)
+
+EXPORT_SYMBOL(callback_getenv)
+EXPORT_SYMBOL(callback_setenv)
+EXPORT_SYMBOL(callback_save_env)
+	
+.data
+__alpha_using_srm:		# For use by bootpheader
+	.long 7			# value is not 1 for link debugging
+	.weak alpha_using_srm; alpha_using_srm = __alpha_using_srm
+__callback_init_done:		# For use by bootpheader
+	.long 7			# value is not 1 for link debugging
+	.weak callback_init_done; callback_init_done = __callback_init_done
+