Kernel: zeta-v2: Faster, smaller map_process_2

diff --git a/Kernel/platform-zeta-v2/zeta-v2.s b/Kernel/platform-zeta-v2/zeta-v2.s
index 644cc53..18bf3d1 100644 (file)
--- a/Kernel/platform-zeta-v2/zeta-v2.s
+++ b/Kernel/platform-zeta-v2/zeta-v2.s
@@ -225,13 +225,6 @@ _program_vectors:
 
        jr map_kernel
 
-;=========================================================================
-; Memory management
-; - kernel pages:     32 - 34
-; - common page:      35
-; - user space pages: 36 - 63
-;=========================================================================
-
 ;=========================================================================
 ; map_process_always - map process pages
 ; Inputs: page table address in #U_DATA__U_PAGE
@@ -263,31 +256,25 @@ map_kernel:
         jr map_process_2_pophl_ret
 
 ;=========================================================================
-; map_process_2 - map process or kernel pages
+; map_process_2 - map process or kernel pages, update mpgsel_cache
 ; Inputs: page table address in HL
 ; Outputs: none, HL destroyed
 ;=========================================================================
 map_process_2:
-       push de
-       push af
-       ld de,#mpgsel_cache             ; paging registers are write only
-                                       ; so cache their content in RAM
-       ld a,(hl)                       ; memory page number for bank #0
-       ld (de),a
-       out (MPGSEL_0),a                ; set bank #0
-       inc hl
-       inc de
-       ld a,(hl)                       ; memory page number for bank #1
-       ld (de),a
-       out (MPGSEL_1),a                ; set bank #1
-       inc hl
-       inc de
-       ld a,(hl)                       ; memory page number for bank #2
-       ld (de),a
-       out (MPGSEL_2),a                ; set bank #2
-       pop af
-       pop de
-       ret
+        push af
+        ld a, (hl)
+        ld (mpgsel_cache+0), a
+        out (MPGSEL_0), a
+        inc hl
+        ld a, (hl)
+        ld (mpgsel_cache+1), a
+        out (MPGSEL_1), a
+        inc hl
+        ld a, (hl)
+        ld (mpgsel_cache+2), a
+        out (MPGSEL_2), a
+        pop af
+        ret
 
 ;=========================================================================
 ; map_restore - restore a saved page mapping