65c816: multiple fixes - pre-empt support

diff --git a/Kernel/lib/65c816.s b/Kernel/lib/65c816.s
index 4ee0721..de81c20 100644 (file)
--- a/Kernel/lib/65c816.s
+++ b/Kernel/lib/65c816.s
@@ -56,11 +56,11 @@ idling:
        rep #$10
        .i16
        ldx     U_DATA__U_PTAB
-       lda     0,x
+       lda     a:0,x
        cmp     #P_READY
        bne     slow_path
        lda     #P_RUNNING
-       sta     P_TAB__P_STATUS_OFFSET,x
+       sta     a:P_TAB__P_STATUS_OFFSET,x
        plx
        stx     sp
        plx                             ; discard 0
@@ -140,10 +140,10 @@ switch_patch_2:
        sep     #$20
        .a8
        lda     #P_RUNNING
-       sta     P_TAB__P_STATUS_OFFSET,x
+       sta     a:P_TAB__P_STATUS_OFFSET,x
        ;       This will only be needed once we swap, and we will need to
        ;       do a few other fixups too
-       lda     P_TAB__P_PAGE_OFFSET,x
+       lda     a:P_TAB__P_PAGE_OFFSET,x
        sta     U_DATA__U_PAGE
        plx     ; stacked kernel space C sp
        stx     sp

diff --git a/Kernel/lowlevel-65c816.s b/Kernel/lowlevel-65c816.s
index 72d0e4a..29478c3 100644 (file)
--- a/Kernel/lowlevel-65c816.s
+++ b/Kernel/lowlevel-65c816.s
@@ -211,10 +211,12 @@ noargs:
 
        lda     #1
        sta     _kernel_flag            ; In kernel mode
+       sta     U_DATA__U_INSYS
        cli                             ; Interrupts now ok
        jsr     _unix_syscall           ; Enter C space
        sei                             ; Interrupts back off
        stz     _kernel_flag
+       stz     U_DATA__U_INSYS
 
        rep     #$10
        .i16
@@ -235,8 +237,7 @@ noargs:
        .i16
 
        lda     U_DATA__U_PAGE
-       tsx
-       sta     3,x
+       sta     3,s
 
        sep     #$10
        .i8
@@ -369,6 +370,7 @@ _doexec:
        stx     ptr1+1          ;       address to execute from
        sei
        stz     _kernel_flag
+       stz     U_DATA__U_INSYS
 
        rep     #$30
        .i16
@@ -537,7 +539,7 @@ join_interrupt_path:
        ldx     istack_switched_sp
        txs
 
-       lda     _kernel_flag
+       lda     U_DATA__U_INSYS
        beq     ret_to_user
 
        ;       Kernel interrupt path may change B and D itself so we must
@@ -559,11 +561,10 @@ join_interrupt_path:
 
 ret_to_user:
        lda     _need_resched
-       jmp     no_preempt
        beq     no_preempt
 
-       lda     #0
-       sta     _need_resched
+
+       stz     _need_resched
 
        ldx     istack_switched_sp
        stx     U_DATA__U_SYSCALL_SP
@@ -582,6 +583,12 @@ ret_to_user:
        lda     #1
        sta     U_DATA__U_INSYS
        ;
+       ;       Mark outselves as idle
+       ;
+       ldx     U_DATA__U_PTAB
+       lda     #P_READY
+       sta     a:P_TAB__P_STATUS_OFFSET,x
+       ;
        ;       Drop back to a8i8 and schedule ourself out
        ;
        sep     #$30
@@ -594,15 +601,19 @@ ret_to_user:
        ;       We will (one day maybe) pop back out here. It's not
        ;       guaranteed (we might be killed off)
        ;
+       rep     #$10
+       .a8
+       .i16
+
        lda     #0
        sta     U_DATA__U_INSYS
+
+       ldx     U_DATA__U_SYSCALL_SP
+       txs
+
        ;
        ;       And exit the handler
        ;
-       rep     #$10
-
-       .a8
-       .i16
 no_preempt:
        ; Discard saved B and D - for user we will compute the correct
        ; one (we could optimize this a shade and only throw on a
@@ -624,11 +635,8 @@ no_preempt:
        ;       process
        ;
 
-       lda     U_DATA__U_PAGE
-
-       tsx
        lda     U_DATA__U_PAGE  ;+1 for split ID
-       sta     9,x             ; Might have moved bank if swapping
+       sta     10,s            ; Might have moved bank if swapping
 
        sep     #$30
        .a8
@@ -965,73 +973,3 @@ sigret_irq:
 syscall_vector:
        jsl     KERNEL_FAR+syscall_entry
        rts
-
-;
-;      Relocation stub (as it's easier to do relocation when in the user
-;      bank than bouncing around and we have no common!). Called with i16
-;      and X holding the binary start, tmp1 the shift and Y the code to
-;      process
-;
-;      Returns with X pointing to end zero (so we can run it twice to do
-;      ZP). We wipe the data as we go since it will become BSS.
-;
-;      Our relocation table lives in BSS start and is a byte table in the
-;      format
-;      0,0     end
-;      0,n     skip n bytes and read next table entry
-;      1-255   skip 1-255 bytes and relocate the byte now pointed at
-;              then read next table entry
-;
-;      Our first table is high bytes of 16bit addresses to relocate (we
-;      keep page alignment). Our second is ZP addresses to relocate.
-;
-;      Call with interrupts off until sure our irq code will get odd
-;      code banks right.
-;
-;      FIXME: move out of stubs - run with code = normal dp = kernel
-;      b = user and it'll work better
-;
-;      FIXME: consider checking if run off end with either X or Y
-;
-relocate:
-       .i16
-       .a8
-       stz tmp2+1      ; FIXME
-reloc_loop:
-       lda 0,x
-       stz 0,x
-       beq multi
-       sta tmp2
-       ; skip 1-255 bytes and then relocate one byte
-       rep #$20
-       .a16
-       tya
-       adc tmp2
-       tay
-       sep #$20
-       .a8
-       ; now relocate
-       lda 0,y
-       clc
-       adc tmp1
-       sta 0,y
-       bra reloc_loop
-multi:
-       .i16
-       .a8
-       inx
-       lda 0,x
-       stz 0,x
-       beq endofreloc          ;       (0,0 -> end)
-       sta tmp2
-       rep #$20
-       .a16
-       tya
-       adc tmp2
-       tay
-       sep #$20
-       .a8
-       bra reloc_loop
-endofreloc:
-       rtl                     ; as called from bank KERNEL
-