From 3ebaf9d7f5ac4ef8a778918bebc0ab553a5ece6d Mon Sep 17 00:00:00 2001
From: Alan Cox <alan@linux.intel.com>
Date: Sun, 17 Feb 2019 23:56:11 +0000
Subject: [PATCH] 8080: add framework for 8085 vectored interrupts and 8214
 interrupts

---
 Kernel/kernel-8080.def | 20 ++++++++++++++++++++
 Kernel/lowlevel-8080.s | 17 ++++++++++-------
 2 files changed, 30 insertions(+), 7 deletions(-)

diff --git a/Kernel/kernel-8080.def b/Kernel/kernel-8080.def
index 6b9c99ac..9ed72d60 100644
--- a/Kernel/kernel-8080.def
+++ b/Kernel/kernel-8080.def
@@ -57,3 +57,23 @@ BUFSIZE                     = 520
 !
 .sect .common			! 4
 .sect .discard			! 5
+
+
+! Currently only used for 8085
+
+#ifndef INT_ENTER
+#define INT_ENTER		! just use the automatic di
+#endif
+
+#ifndef INT_EXIT
+#define INT_EXIT		! nothing needed by default
+#endif
+
+#ifndef EI
+#define EI ei
+#endif
+
+#ifndef DI
+#define DI di
+#endif
+
diff --git a/Kernel/lowlevel-8080.s b/Kernel/lowlevel-8080.s
index cae884a9..1fc5a175 100644
--- a/Kernel/lowlevel-8080.s
+++ b/Kernel/lowlevel-8080.s
@@ -44,10 +44,11 @@ deliver_signals_2:
 	!	FIXME: if we ever have 8080 binaries with different load
 	!	addresses we will need to fix this
 	!
+	EI
 	lhld PROGLOAD+16		! signal vector
 	pchl
 signal_return:
-	di
+	DI
 	lxi h,0
 	dad sp
 	shld U_DATA__U_SYSCALL_SP
@@ -64,7 +65,6 @@ signal_return:
 .define unix_syscall_entry
 
 unix_syscall_entry:
-	di
 	push b		! Must preserve the frame pointer
 	lxi h,6		! Find arguments on stack frame
 
@@ -95,6 +95,7 @@ unix_syscall_entry:
 	inx h
 	mov a,m
 	sta U_DATA__U_ARGN+7
+	DI
 	! We are now in kernel space
 	mvi a,1
 	sta U_DATA__U_INSYS
@@ -108,14 +109,14 @@ unix_syscall_entry:
 	! Now map the kernel and call it
 	!
 	call map_kernel_di
-	ei
+	EI
 	call _unix_syscall
 	xchg
 	!
 	! Remember fork and execve don't necessarily return this way and fork
 	! can do it twice
 	!
-	di
+	DI
 	call map_process_always
 	xra a
 	sta U_DATA__U_INSYS
@@ -144,7 +145,7 @@ not_error:
 unix_pop:
 	pop b
 	! ret must directly follow the ei
-	ei
+	EI
 	ret
 via_signal:
 	!
@@ -171,7 +172,7 @@ via_signal:
 .define _doexec
 
 _doexec:
-	di
+	DI
 	call map_process_always
 	pop b
 	pop d
@@ -181,7 +182,7 @@ _doexec:
 	sta U_DATA__U_INSYS
 	xchg
 	lxi d,PROGLOAD
-	ei
+	EI
 	pchl
 !
 !	NULL trap. Must live in common space 
@@ -242,6 +243,7 @@ nmimsg:
 
 interrupt_handler:
 	push psw
+	INT_ENTER
 	push b
 	push d
 	push h
@@ -321,6 +323,7 @@ interrupt_pop:
 	pop h
 	pop d
 	pop b
+	INT_EXIT
 	pop psw
 	ei
 	ret
-- 
2.34.1