From 29e208d56d6901e33a4952d39155f3bafc98ed08 Mon Sep 17 00:00:00 2001
From: Tormod Volden <debian.tormod@gmail.com>
Date: Wed, 3 Jun 2015 22:28:22 +0200
Subject: [PATCH] dragon-nx32: Small bank copy optimization

Use direct page addressing for the bank switching. Speeds
up forking a tiny bit.

Signed-off-by: Tormod Volden <debian.tormod@gmail.com>
---
 Kernel/platform-dragon-nx32/mem-nx32.s | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/Kernel/platform-dragon-nx32/mem-nx32.s b/Kernel/platform-dragon-nx32/mem-nx32.s
index 2a1ebf58..73ee7a4a 100644
--- a/Kernel/platform-dragon-nx32/mem-nx32.s
+++ b/Kernel/platform-dragon-nx32/mem-nx32.s
@@ -100,15 +100,19 @@ map_restore
 ; optimized bank copy for fork
 ; src bank in A, dst bank in B, start in X, end in U
 copybank
+	pshs dp,a
+	lda #0xff
+	tfr a,dp
+	puls a
 	stu cmpend+1	; self-modiying code FTW
-copyf	sta banksel
+copyf	sta <banksel
 	ldu ,x
-	stb banksel
+	stb <banksel
 	stu ,x++
 cmpend	cmpx #0
 	blo copyf
 	stb map_copy
-	rts
+	puls dp,pc
 
 map_store	.db 0
 map_copy	.db 0
-- 
2.34.1