65c816: gets the signal handling path via syscall closer

We now call the signal handler correctly, but the handler return blows up

diff --git a/Kernel/lowlevel-65c816.s b/Kernel/lowlevel-65c816.s
index 7873933..470c25e 100644 (file)
--- a/Kernel/lowlevel-65c816.s
+++ b/Kernel/lowlevel-65c816.s
@@ -197,8 +197,8 @@ noargs:
        .i16
 
        phx                             ; push user sp onto stack so we can
-                                       ; see it (only brk() needs it, nor
-                                       ; is it needed for save/restore)
+                                       ; see it (only brk() needs it but it
+                                       ; is needed for save/restore)
        tsx
        stx     U_DATA__U_SYSCALL_SP
        ldx     #kstack_top-1
@@ -280,27 +280,35 @@ signal_out:
        .a8
        .i8
        stz     U_DATA__U_CURSIG
+
+       ; TRACE FIXME
+       pha
+       lda     #1
+       sta     $FE41                   ; trace on
+       pla
        
        ;
        ;       Fixme stack correct U_DATA in x y a
        ;
 
-       rep     #$10
+       tax                             ; save signal into x
+       rep     #$30
+       .a16
        .i16
        ply                             ; user stack pointer to go to sp
-       tsx
-       dex                             ; move past existing frame P
-       dex                             ; return PC
-       dex                             ; return PC
-                                       ; lose the bank
-       txs
-       sep     #$10
+       lda     1,s                     ; move the return up
+       sta     2,s
+       rep     #$30
        .i8
+       pla                             ; and drop the byte from removing
+                                       ; the bank
+       txa                             ; signal back into a
+
        ; Stack the signal return (the signal itself can cause syscalls)
        ; Be careful here stack ops are currently going to user stack but
        ; data ops to kernel. Don't mix them up!
-       pea     sigret
-       phx                             ; signal number
+       pea     sigret-1                ; RTL incs
+       pha                             ; signal number
        phy                             ; temporarily save C sp value
        asl a                           ; vector offset
        tay
@@ -317,9 +325,13 @@ signal_out:
        ; Needs to change for split I/D
        lda     U_DATA__U_PAGE          ; target code page
        pha
-       pea     PROGLOAD+20             ; trap handler in user app
        pha
        plb                             ; get the right user data bank
+
+       ldx     PROGLOAD+20             ; trap handler in user app
+       dex                             ; rtl incs this
+       phx
+
        jsr     setdp
        sty     sp                      ; and finally restore the user C sp
        sep     #$10                    ; i8a8 on entry to handler
@@ -666,7 +678,7 @@ signal_exit:
 
        sep     #$20
        .a8
-       pea     sigret_irq      ; signal return
+       pea     sigret_irq-1    ; signal return
        sep     #$10
        .i8
        phy                     ; signal code
@@ -689,7 +701,7 @@ signal_exit:
        .i16
        ldx     #0
        txy
-       pea     PROGLOAD+20
+       pea     PROGLOAD+20-1
        sep     #$30
        .i8
        .a8