Commit 8eec56b6 authored by Jens Wilke's avatar Jens Wilke
Browse files

added optional write protection for memory regions

parent a28c801a

cross.fs

+39 −10
Original line number Diff line number Diff line
@@ -1235,7 +1235,8 @@ tbits/char bits/byte / Constant tbyte 
\ Variables                                            06oct92py



Variable image

Variable tlast    TNIL tlast !  \ Last name field

Variable (tlast)    

(tlast) Value tlast TNIL tlast !  \ Last name field

Variable tlastcfa \ Last code field

Variable bit$
@@ -1259,11 +1260,11 @@ Variable region-link \ linked list with all regions 
Variable mirrored-link          \ linked list for mirrored regions

0 dup mirrored-link ! region-link !





: >rname 7 cells + ;

: >rbm   4 cells + ;

: >rname 8 cells + ;

: >rbm   4 cells + ; \ bitfield per cell witch indicates relocation

: >rmem  5 cells + ;

: >rtype 6 cells + ;

: >rtype 6 cells + ; \ field per cell witch points to a type struct

: >rrom 7 cells + ;  \ a -1 indicates that this region is rom

: >rlink 3 cells + ;

: >rdp 2 cells + ;

: >rlen cell+ ;
@@ -1283,7 +1284,7 @@ Variable mirrored-link \ linked list for mirrored regions 
	save-input create restore-input throw

	here last-defined-region !

	over ( startaddr ) , ( length ) , ( dp ) ,

	region-link linked 0 , 0 , 0 , bl word count string,

	region-link linked 0 , 0 , 0 , 0 , bl word count string,

  ELSE	\ store new parameters in region

        bl word drop

	>body (region)
@@ -1301,11 +1302,15 @@ Variable mirrored-link \ linked list for mirrored regions 
\G returns the total area

  dup >rstart @ swap >rlen @ ;



: mirrored                              

\G mark a region as mirrored

: mirrored ( -- )                              

\G mark last defined region as mirrored

  mirrored-link

  align linked last-defined-region @ , ;



: writeprotected

\G mark a region as write protected

  -1 last-defined-region @ >rrom ! ;



: .addr ( u -- )

\G prints a 16 or 32 Bit nice hex value

  base @ >r hex
@@ -1561,6 +1566,18 @@ bigendian 
  \ add regions real address in our memory

  r> >rmem @ + ;



: (>regionramimage) ( taddr -- 'taddr )

\G same as (>regionimage) but aborts if the region is rom

  dup

  \ find region we want to address

  taddr>region-abort

  >r

  r@ >rrom @ ABORT" CROSS: region is write-protected!"

  \ calculate offset in region

  r@ >rstart @ -

  \ add regions real address in our memory

  r> >rmem @ + ;



: (>regionbm) ( taddr -- 'taddr bitmaskbaseaddr )

  dup

  \ find region we want to address
@@ -1609,6 +1626,7 @@ CREATE Bittable 80 c, 40 c, 20 c, 10 c, 8 c, 4 c, 2 c, 1 c, 
: (>image) ( taddr -- absaddr ) image @ + ;



DEFER >image

DEFER >ramimage

DEFER relon

DEFER reloff

DEFER correcter
@@ -1618,12 +1636,23 @@ T has? relocate H 
' (relon) IS relon

' (reloff) IS reloff

' (>regionimage) IS >image

' (>regionimage) IS >ramimage

[ELSE]

' drop IS relon

' drop IS reloff

' (>regionimage) IS >image

' (>regionimage) IS >ramimage

[THEN]



: enforce-writeprotection ( -- )

  ['] (>regionramimage) IS >ramimage ;



: relax-writeprotection ( -- )

  ['] (>regionimage) IS >ramimage ;



: writeprotection-relaxed? ( -- )

  ['] >ramimage >body @ ['] (>regionimage) = ;



\ Target memory access                                 06oct92py



: align+  ( taddr -- rest )
@@ -1641,9 +1670,9 @@ T has? relocate H 
    dup cfalign+ + ;



: @  ( taddr -- w )     >image S@ ;

: !  ( w taddr -- )     >image S! ;

: !  ( w taddr -- )     >ramimage S! ;

: c@ ( taddr -- char )  >image Sc@ ;

: c! ( char taddr -- )  >image Sc! ;

: c! ( char taddr -- )  >ramimage Sc! ;

: 2@ ( taddr -- x1 x2 ) T dup cell+ @ swap @ H ;

: 2! ( x1 x2 taddr -- ) T tuck ! cell+ ! H ;