Add GPT support
Add support for booting from a GPT partitioned disk.
Signed-off-by: Avik Sil <aviksil@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
diff --git a/slof/fs/packages/disk-label.fs b/slof/fs/packages/disk-label.fs
index 364e67e..c625edf 100644
--- a/slof/fs/packages/disk-label.fs
+++ b/slof/fs/packages/disk-label.fs
@@ -37,6 +37,9 @@
0 INSTANCE VALUE args
0 INSTANCE VALUE args-len
+0 INSTANCE VALUE gpt-part-size
+0 INSTANCE VALUE seek-pos
+
INSTANCE VARIABLE block# \ variable to store logical sector#
INSTANCE VARIABLE hit# \ partition counter
@@ -73,6 +76,34 @@
CONSTANT /partition-entry
+STRUCT
+ 8 field gpt>signature
+ 4 field gpt>revision
+ 4 field gpt>header-size
+ 4 field gpt>header-crc32
+ 4 field gpt>reserved
+ 8 field gpt>current-lba
+ 8 field gpt>backup-lba
+ 8 field gpt>first-lba
+ 8 field gpt>last-lba
+ 10 field gpt>disk-guid
+ 8 field gpt>part-entry-lba
+ 4 field gpt>num-part-entry
+ 4 field gpt>part-entry-size
+ 4 field gpt>part-array-crc32
+ 1a4 field gpt>reserved
+
+CONSTANT /gpt-header
+
+STRUCT
+ 10 field gpt-part-entry>part-type-guid
+ 10 field gpt-part-entry>part-guid
+ 8 field gpt-part-entry>first-lba
+ 8 field gpt-part-entry>last-lba
+ 8 field gpt-part-entry>attribute
+ 48 field gpt-part-entry>part-name
+
+CONSTANT /gpt-part-entry
\ Defined by IEEE 1275-1994 (3.8.1)
@@ -128,10 +159,25 @@
THEN
;
+: partition>part-entry ( partition -- part-entry )
+ 1- /partition-entry * block mbr>partition-table +
+;
+
+: partition>start-sector ( partition -- sector-offset )
+ partition>part-entry part-entry>sector-offset l@-le
+;
\ This word returns true if the currently loaded block has _NO_ MBR magic
: no-mbr? ( -- true|false )
- 0 read-sector block mbr>magic w@-le aa55 <>
+ 0 read-sector
+ 1 partition>part-entry part-entry>id c@ ee = IF TRUE EXIT THEN \ GPT partition found
+ block mbr>magic w@-le aa55 <>
+;
+
+\ This word returns true if the currently loaded block has _NO_ GPT partition id
+: no-gpt? ( -- true|false )
+ 0 read-sector
+ 1 partition>part-entry part-entry>id c@ ee <>
;
: pc-extended-partition? ( part-entry-addr -- true|false )
@@ -142,14 +188,6 @@
or or ( true|false )
;
-: partition>part-entry ( partition -- part-entry )
- 1- /partition-entry * block mbr>partition-table +
-;
-
-: partition>start-sector ( partition -- sector-offset )
- partition>part-entry part-entry>sector-offset l@-le
-;
-
: count-dos-logical-partitions ( -- #logical-partitions )
no-mbr? IF 0 EXIT THEN
0 5 1 DO ( current )
@@ -313,11 +351,69 @@
drop 0
;
+\ Check for GPT PReP partition GUID
+9E1A2D38 CONSTANT GPT-PREP-PARTITION-1
+C612 CONSTANT GPT-PREP-PARTITION-2
+4316 CONSTANT GPT-PREP-PARTITION-3
+AA26 CONSTANT GPT-PREP-PARTITION-4
+8B49521E5A8B CONSTANT GPT-PREP-PARTITION-5
+
+: gpt-prep-partition? ( -- true|false )
+ block gpt-part-entry>part-type-guid l@-le GPT-PREP-PARTITION-1 = IF
+ block gpt-part-entry>part-type-guid 4 + w@-le
+ GPT-PREP-PARTITION-2 = IF
+ block gpt-part-entry>part-type-guid 6 + w@-le
+ GPT-PREP-PARTITION-3 = IF
+ block gpt-part-entry>part-type-guid 8 + w@
+ GPT-PREP-PARTITION-4 = IF
+ block gpt-part-entry>part-type-guid a + w@
+ block gpt-part-entry>part-type-guid c + l@ swap lxjoin
+ GPT-PREP-PARTITION-5 = IF
+ TRUE EXIT
+ THEN
+ THEN
+ THEN
+ THEN
+ THEN
+ FALSE
+;
+
+: load-from-gpt-prep-partition ( addr -- size )
+ no-gpt? IF FALSE EXIT THEN
+ debug-disk-label? IF
+ cr ." GPT partition found " cr
+ THEN
+
+ 1 read-sector block gpt>part-entry-lba l@-le
+ block-size * to seek-pos
+ block gpt>part-entry-size l@-le to gpt-part-size
+ block gpt>num-part-entry l@-le dup 0= IF FALSE EXIT THEN
+ 1+ 1 ?DO
+ seek-pos 0 seek drop
+ block gpt-part-size read drop gpt-prep-partition? IF
+ debug-disk-label? IF
+ ." GPT PReP partition found " cr
+ THEN
+ block gpt-part-entry>first-lba x@ xbflip
+ block gpt-part-entry>last-lba x@ xbflip
+ over - 1+ ( addr offset len )
+ swap ( addr len offset )
+ block-size * to part-offset
+ 0 0 seek drop ( addr len )
+ block-size * read ( size )
+ UNLOOP EXIT
+ THEN
+ seek-pos gpt-part-size i * + to seek-pos
+ LOOP
+ FALSE
+;
\ load from a bootable partition
: load-from-boot-partition ( addr -- size )
- load-from-dos-boot-partition
+ load-from-dos-boot-partition dup 0= IF
+ drop load-from-gpt-prep-partition
+ THEN
\ More boot partition formats ...
;
