From 83c63a65c3766daaafbcd6a48b7cfb472b2de21e Mon Sep 17 00:00:00 2001
From: Marco van den Heuvel <blackystardust68@yahoo.com>
Date: Wed, 2 Dec 2015 00:14:56 -0800
Subject: [PATCH] optimized the sei/cli pairing a bit.

---
 libsrc/c128/emd/c128-efnram.s | 27 +++++++++++++--------------
 libsrc/c128/emd/c128-ifnram.s | 31 +++++++++++++++----------------
 2 files changed, 28 insertions(+), 30 deletions(-)

diff --git a/libsrc/c128/emd/c128-efnram.s b/libsrc/c128/emd/c128-efnram.s
index 4d179da83..78882fa6e 100755
--- a/libsrc/c128/emd/c128-efnram.s
+++ b/libsrc/c128/emd/c128-efnram.s
@@ -64,7 +64,6 @@ window:         .res    256             ; Memory "window"
 ;
 
 INSTALL:
-        sei
         ldx     #0
         stx     ptr1
         ldx     #$80
@@ -74,20 +73,22 @@ INSTALL:
         stx     STAVEC
         ldy     #0
         ldx     #MMU_CFG_EXT_FROM
+        sei
         jsr     FETCH
         tax
         inx
         txa
         sta     tmp1
         ldx     #MMU_CFG_EXT_FROM
+        sei
         jsr     STASH
         ldx     #MMU_CFG_EXT_FROM
         jsr     FETCH
+        cli
         cmp     tmp1
         beq     @ram_present
         lda     #<EM_ERR_NO_DEVICE
         ldx     #>EM_ERR_NO_DEVICE
-        cli
         rts
 
 @ram_present:
@@ -96,7 +97,6 @@ INSTALL:
         stx     curpage+1               ; Invalidate the current page
         inx
         txa                             ; A = X = EM_ERR_OK
-        cli
 ;       rts                             ; Run into UNINSTALL instead
 
 ; ------------------------------------------------------------------------
@@ -123,8 +123,7 @@ PAGECOUNT:
 ; by the driver.
 ;
 
-MAP:    sei
-        sta     curpage
+MAP:    sta     curpage
         stx     curpage+1               ; Remember the new page
 
         clc
@@ -135,6 +134,7 @@ MAP:    sei
 
         lda     #<ptr1
         sta     FETVEC
+        sei
 
 ; Transfer one page
 
@@ -146,9 +146,9 @@ MAP:    sei
 
 ; Return the memory window
 
+        cli
         lda     #<window
         ldx     #>window                ; Return the window address
-        cli
         rts
 
 ; ------------------------------------------------------------------------
@@ -163,8 +163,7 @@ USE:    sta     curpage
 ; ------------------------------------------------------------------------
 ; COMMIT: Commit changes in the memory window to extended storage.
 
-COMMIT: sei
-        lda     curpage                 ; Get the current page
+COMMIT: lda     curpage                 ; Get the current page
         ldx     curpage+1
         bmi     done                    ; Jump if no page mapped
 
@@ -176,6 +175,7 @@ COMMIT: sei
 
         lda     #<ptr1
         sta     STAVEC
+        sei
 
 ; Transfer one page. Y must be zero on entry
 
@@ -184,11 +184,11 @@ COMMIT: sei
         jsr     STASH
         iny
         bne     @L1
+        cli
 
 ; Done
 
-done:   cli
-        rts
+done:   rts
 
 ; ------------------------------------------------------------------------
 ; COPYFROM: Copy from extended into linear memory. A pointer to a structure
@@ -197,7 +197,6 @@ done:   cli
 ;
 
 COPYFROM:
-        sei
         sta     ptr3
         stx     ptr3+1                  ; Save the passed em_copy pointer
 
@@ -228,6 +227,7 @@ COPYFROM:
 ; Copy full pages
 
         ldy     #$00
+        sei
 @L1:    ldx     #MMU_CFG_EXT_FROM
         jsr     FETCH
         sta     (ptr2),y
@@ -252,7 +252,6 @@ COPYFROM:
         iny
         dec     tmp1
         bne     @L3
-
 ; Done
 
 @L4:    cli
@@ -264,8 +263,7 @@ COPYFROM:
 ; The function must not return anything.
 ;
 
-COPYTO: sei
-        sta     ptr3
+COPYTO: sta     ptr3
         stx     ptr3+1                  ; Save the passed em_copy pointer
 
         ldy     #EM_COPY::OFFS
@@ -294,6 +292,7 @@ COPYTO: sei
 
 ; Copy full pages
 
+        sei
         ldy     #$00
 @L1:    lda     (ptr2),y
         ldx     #MMU_CFG_EXT_FROM
diff --git a/libsrc/c128/emd/c128-ifnram.s b/libsrc/c128/emd/c128-ifnram.s
index e670fe069..ad482e663 100755
--- a/libsrc/c128/emd/c128-ifnram.s
+++ b/libsrc/c128/emd/c128-ifnram.s
@@ -1,5 +1,5 @@
 ;
-; Extended memory driver for the C128 Internal Function RAM. Driver works
+; Extended memory driver for the C128 External Function RAM. Driver works
 ; without problems when statically linked.
 ;
 ; Marco van den Heuvel, 2015-11-30
@@ -18,7 +18,7 @@
 ; ------------------------------------------------------------------------
 ; Header. Includes jump table
 
-        module_header   _c128_ifnram_emd
+        module_header   _c128_efnram_emd
 
 ; Driver signature
 
@@ -64,7 +64,6 @@ window:         .res    256             ; Memory "window"
 ;
 
 INSTALL:
-        sei
         ldx     #0
         stx     ptr1
         ldx     #$80
@@ -74,20 +73,22 @@ INSTALL:
         stx     STAVEC
         ldy     #0
         ldx     #MMU_CFG_INT_FROM
+        sei
         jsr     FETCH
         tax
         inx
         txa
         sta     tmp1
         ldx     #MMU_CFG_INT_FROM
+        sei
         jsr     STASH
         ldx     #MMU_CFG_INT_FROM
         jsr     FETCH
+        cli
         cmp     tmp1
         beq     @ram_present
         lda     #<EM_ERR_NO_DEVICE
         ldx     #>EM_ERR_NO_DEVICE
-        cli
         rts
 
 @ram_present:
@@ -96,7 +97,6 @@ INSTALL:
         stx     curpage+1               ; Invalidate the current page
         inx
         txa                             ; A = X = EM_ERR_OK
-        cli
 ;       rts                             ; Run into UNINSTALL instead
 
 ; ------------------------------------------------------------------------
@@ -123,8 +123,7 @@ PAGECOUNT:
 ; by the driver.
 ;
 
-MAP:    sei
-        sta     curpage
+MAP:    sta     curpage
         stx     curpage+1               ; Remember the new page
 
         clc
@@ -135,6 +134,7 @@ MAP:    sei
 
         lda     #<ptr1
         sta     FETVEC
+        sei
 
 ; Transfer one page
 
@@ -146,9 +146,9 @@ MAP:    sei
 
 ; Return the memory window
 
+        cli
         lda     #<window
         ldx     #>window                ; Return the window address
-        cli
         rts
 
 ; ------------------------------------------------------------------------
@@ -163,8 +163,7 @@ USE:    sta     curpage
 ; ------------------------------------------------------------------------
 ; COMMIT: Commit changes in the memory window to extended storage.
 
-COMMIT: sei
-        lda     curpage                 ; Get the current page
+COMMIT: lda     curpage                 ; Get the current page
         ldx     curpage+1
         bmi     done                    ; Jump if no page mapped
 
@@ -176,6 +175,7 @@ COMMIT: sei
 
         lda     #<ptr1
         sta     STAVEC
+        sei
 
 ; Transfer one page. Y must be zero on entry
 
@@ -184,11 +184,11 @@ COMMIT: sei
         jsr     STASH
         iny
         bne     @L1
+        cli
 
 ; Done
 
-done:   cli
-        rts
+done:   rts
 
 ; ------------------------------------------------------------------------
 ; COPYFROM: Copy from extended into linear memory. A pointer to a structure
@@ -197,7 +197,6 @@ done:   cli
 ;
 
 COPYFROM:
-        sei
         sta     ptr3
         stx     ptr3+1                  ; Save the passed em_copy pointer
 
@@ -228,6 +227,7 @@ COPYFROM:
 ; Copy full pages
 
         ldy     #$00
+        sei
 @L1:    ldx     #MMU_CFG_INT_FROM
         jsr     FETCH
         sta     (ptr2),y
@@ -252,7 +252,6 @@ COPYFROM:
         iny
         dec     tmp1
         bne     @L3
-
 ; Done
 
 @L4:    cli
@@ -264,8 +263,7 @@ COPYFROM:
 ; The function must not return anything.
 ;
 
-COPYTO: sei
-        sta     ptr3
+COPYTO: sta     ptr3
         stx     ptr3+1                  ; Save the passed em_copy pointer
 
         ldy     #EM_COPY::OFFS
@@ -294,6 +292,7 @@ COPYTO: sei
 
 ; Copy full pages
 
+        sei
         ldy     #$00
 @L1:    lda     (ptr2),y
         ldx     #MMU_CFG_INT_FROM
-- 
2.39.5