From 8b00636f6687bf9e8d524322b496ca03797db4c9 Mon Sep 17 00:00:00 2001
From: Aaron Culliney <asc_at_bitr0t_com>
Date: Sat, 10 May 2014 11:56:54 -0700
Subject: [PATCH] refactor PAGE2 switch to C

---
 src/asm386/memory.S | 57 ---------------------------------------------
 src/vm.c            | 52 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 52 insertions(+), 57 deletions(-)

diff --git a/src/asm386/memory.S b/src/asm386/memory.S
index 7cfabd49..a3a862ee 100644
--- a/src/asm386/memory.S
+++ b/src/asm386/memory.S
@@ -149,63 +149,6 @@
 	  			enabled.
 	   ----------------------------------------------------------------- */
 
-/* PAGE2 off. if 80STORE on then we use main text page1, and if HIRES
-	on we also use main hires page1, regardless of RAMRD and
-	RAMWRT. */
-E(iie_page2_off)
-		testl	$SS_PAGE2, SN(softswitches)	# already off?
-		jz	ram_nop
-		andl	$~(SS_PAGE2|SS_SCREEN), SN(softswitches)
-		testl	$SS_80STORE, SN(softswitches)
-		jz	_iie_page2_off_hires_off	# no 80STORE
-		andl	$~(SS_TEXTRD|SS_TEXTWRT), SN(softswitches)
-		movl	$SN(apple_ii_64k), SN(base_textrd)
-		movl	$SN(apple_ii_64k), SN(base_textwrt)
-		testl	$SS_HIRES, SN(softswitches)
-		jz	_iie_page2_off_hires_off	# no HIRES
-		andl	$~(SS_HGRRD|SS_HGRWRT), SN(softswitches)
-		movl	$SN(apple_ii_64k), SN(base_hgrrd)
-		movl	$SN(apple_ii_64k), SN(base_hgrwrt)
-_iie_page2_off_hires_off:
-		pushal
-		pushl	$0				# page 1 main
-		call	SN(video_setpage)
-		addl	$4, %esp
-		popal
-/* 		call	SN(video_redraw)# redraw */
-		ret
-
-
-/* PAGE2 on.  if 80STORE on then we use aux text page 1, and if HIRES
-	on we also use aux hires page 1, regardless of RAMRD and
-	RAMWRT. */
-E(iie_page2_on)
-		testl	$SS_PAGE2, SN(softswitches)	# already on?
-		jnz	ram_nop
-		orl	$SS_PAGE2, SN(softswitches)
-		testl	$SS_80STORE, SN(softswitches)
-		jz	_iie_page2_on_80store_off	# no 80STORE
-		orl	$(SS_TEXTRD|SS_TEXTWRT), SN(softswitches)
-		movl	$SN(apple_ii_64k)+BANK2, SN(base_textrd)
-		movl	$SN(apple_ii_64k)+BANK2, SN(base_textwrt)
-		testl	$(SS_HIRES), SN(softswitches)
-		jz	_iie_page2_on_cont
-		orl	$(SS_HGRRD|SS_HGRWRT), SN(softswitches)
-		movl	$SN(apple_ii_64k)+BANK2, SN(base_hgrrd)
-		movl	$SN(apple_ii_64k)+BANK2, SN(base_hgrwrt)
-_iie_page2_on_cont:
-		ret
-
-_iie_page2_on_80store_off:				# no 80STORE
-		orl	$SS_SCREEN, SN(softswitches)
-		pushal
-		pushl	$1				# page 2 main
-		call	SN(video_setpage)
-		addl	$4, %esp
-		popal
-/* 		call	SN(video_redraw)# redraw */
-		ret
-
 E(read_switch_graphics)
 		testl	$SS_TEXT, SN(softswitches)
 		jz	ram_nop
diff --git a/src/vm.c b/src/vm.c
index d3f5e70f..3ac415c2 100644
--- a/src/vm.c
+++ b/src/vm.c
@@ -61,3 +61,55 @@ GLUE_C_READ(speaker_toggle)
     return 0;
 }
 
+// ----------------------------------------------------------------------------
+// Softswitches
+
+GLUE_C_READ(iie_page2_off)
+{
+    if (!(softswitches & SS_PAGE2)) {
+        return 0x0; // TODO: no early return?
+    }
+
+    softswitches &= ~(SS_PAGE2|SS_SCREEN);
+
+    if (softswitches & SS_80STORE) {
+        softswitches &= ~(SS_TEXTRD|SS_TEXTWRT);
+        base_textrd  = apple_ii_64k[0];
+        base_textwrt = apple_ii_64k[0];
+        if (softswitches & SS_HIRES) {
+            softswitches &= ~(SS_HGRRD|SS_HGRWRT);
+            base_hgrrd  = apple_ii_64k[0];
+            base_hgrwrt = apple_ii_64k[0];
+        }
+    }
+
+    video_setpage(0);
+
+    return 0x0;
+}
+
+GLUE_C_READ(iie_page2_on)
+{
+    if (softswitches & SS_PAGE2) {
+        return 0x0; // TODO: no early return?
+    }
+
+    softswitches |= SS_PAGE2;
+
+    if (softswitches & SS_80STORE) {
+        softswitches |= (SS_TEXTRD|SS_TEXTWRT);
+        base_textrd  = apple_ii_64k[1];
+        base_textwrt = apple_ii_64k[1];
+        if (softswitches & SS_HIRES) {
+            softswitches |= (SS_HGRRD|SS_HGRWRT);
+            base_hgrrd  = apple_ii_64k[1];
+            base_hgrwrt = apple_ii_64k[1];
+        }
+    } else {
+        softswitches |= SS_SCREEN;
+        video_setpage(1);
+    }
+
+    return 0x0;
+}
+