Encode FDT properties as string when they contain a valid ASCII string.

There are a lot of properties in the FDT that contain a string, but commands
like ".properties" only displayed them as byte array since all properties
were encoded with "encode-bytes". Now the code tries to detect valid ASCII
strings and encodes such properties with "encode-string" instead.

Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>

3 files changed, 29 insertions, 12 deletions

diff --git a/board-qemu/slof/fdt.fs b/board-qemu/slof/fdt.fs
index a6de122..850a687 100644
--- a/board-qemu/slof/fdt.fs
+++ b/board-qemu/slof/fdt.fs
@@ -119,6 +119,23 @@ fdt-check-header
 : fdt-create-dec  s" decode-unit" $CREATE , DOES> @ hex-decode-unit ;
 : fdt-create-enc  s" encode-unit" $CREATE , DOES> @ hex-encode-unit ;
 
+\ Check whether array contains an zero-terminated ASCII string:
+: fdt-prop-is-string?  ( addr len -- string? )
+   dup 1 < IF 2drop FALSE EXIT THEN                \ Check for valid length
+   1-
+   2dup + c@ 0<> IF 2drop FALSE EXIT THEN          \ Check zero-termination
+   test-string
+;
+
+\ Encode fdt property to OF property
+: fdt-encode-prop  ( addr len -- )
+   2dup fdt-prop-is-string? IF
+      1- encode-string
+   ELSE
+      encode-bytes
+   THEN
+;
+
 \ Method to unflatten a node
 : fdt-unflatten-node ( start -- end )
   \ this can and will recurse
@@ -159,8 +176,8 @@ fdt-check-header
       drop dup			( drop tag, dup addr     : a1 a1 )
       dup l@ dup rot 4 +	( fetch size, stack is   : a1 s s a2)
       dup l@ swap 4 +		( fetch nameid, stack is : a1 s s i a3 )
-      rot                       ( we now have: a1 s i a3 s )
-      encode-bytes rot		( a1 s pa ps i)
+      rot			( we now have: a1 s i a3 s )
+      fdt-encode-prop rot	( a1 s pa ps i)
       fdt-fetch-string		( a1 s pa ps na ns )
       2dup s" reg" str= IF
           2swap 2dup fdt-reg-unit 2swap
diff --git a/slof/fs/base.fs b/slof/fs/base.fs
index 4fc8ad4..bb95b2d 100644
--- a/slof/fs/base.fs
+++ b/slof/fs/base.fs
@@ -121,6 +121,16 @@ CONSTANT <2constant>
 : str= ( str1 len1 str2 len2 -- equal? )
   rot over <> IF 3drop false ELSE comp 0= THEN ;
 
+: test-string ( param len -- true | false )
+   0 ?DO
+      dup i + c@                     \ Get character / byte at current index
+      dup 20 <  swap 7e >  OR IF     \ Is it out of range 32 to 126 (=ASCII)
+         drop FALSE UNLOOP EXIT      \ FALSE means: No ASCII string
+      THEN
+   LOOP
+   drop TRUE    \ Only ASCII found --> it is a string
+;
+
 : #aligned ( adr alignment -- adr' ) negate swap negate and negate ;
 : #join  ( lo hi #bits -- x )  lshift or ;
 : #split ( x #bits -- lo hi )  2dup rshift dup >r swap lshift xor r> ;
diff --git a/slof/fs/envvar.fs b/slof/fs/envvar.fs
index cdf9226..70223cc 100644
--- a/slof/fs/envvar.fs
+++ b/slof/fs/envvar.fs
@@ -73,16 +73,6 @@ wordlist CONSTANT envvars
 : test-int ( param len -- true | false )
   drop c@ isdigit if true else false then ;
 
-: test-string ( param len -- true | false )
-   0 ?DO
-      dup i + c@                     \ Get character / byte at current index
-      dup 20 <  swap 7e >  OR IF     \ Is it out of range 32 to 126 (=ASCII)
-         drop FALSE UNLOOP EXIT      \ FALSE means: No ASCII string
-      THEN
-   LOOP
-   drop TRUE    \ Only ASCII found --> it is a string
-;
-
 : findtype ( param len name len -- param len name len type )
    2dup findenv dup 0= \ try to find type of envvar
    IF             \ no type found