Merge pull request #1 from rkurbatov/adaptec-284x-patch-2.00

Adaptec 284xA BIOS v2.0 patch

Author: karcherm

.github/workflows/main.yml

@@ -20,13 +20,15 @@ jobs:
         run: |
           jwasm -Zm -Fo274x-211.obj 274x-211.asm
           jwasm -Zm -Fo284x-101.obj 284x-101.asm
+          jwasm -Zm -Fo284x-200.obj 284x-200.asm
           jwasm -Zm -Foa7-142.obj a7-142.asm
       - uses: actions/upload-artifact@v2
         with:
           name: scsi_edd
           path: |
             274x-211.obj
             284x-101.obj
+            284x-200.obj
             a7-142.obj
             bios16k.map
             bios1632.map

.gitignore

@@ -1,3 +1,4 @@
+.idea
 *.obj
 *.lst
 *.bin 

284x-200.asm

@@ -0,0 +1,21 @@
+ResetLocalStateOfs  = 0CA8h
+SetTargetOfs        = 0CDCh
+ExecuteCommandOfs   = 0E94h
+SetDataAddressOfs   = 0F52h
+Int13_DispatchOfs   = 12D8h
+I13_DispatcherOfs   = 147Bh
+Func_UnsupportedOfs = 14ABh
+Func09_AlwaysOKOfs  = 17BAh
+MyInt15Ofs          = 1910h
+MyInt15InstallOfs   = 2D74h  ; Not really. This function is missing, but there
+                             ; is a lot of empty space in the 284x BIOS
+VersionOfs          = 4068h
+
+PATCH_VERSION   MACRO
+        ;db     "/2842VL BIOS v1.01 "
+        db      " BIOS v2.0/EDD 1.0 "
+                ENDM
+
+INCLUDE aic7770.asm
+
+END

README.md

@@ -12,10 +12,11 @@ To apply an object file as patch, my tool [omfpatch](https://github.com/karcherm
 
 Patches for following SCSI BIOSes is included
 
-Controller | Version | patch object | map file     | ROM chip size
------------|---------|--------------|--------------|---------------
-AHA-274x   |  2.11   | 274x-211.obj | bios16k.map  | 32KB (256kBit)
-AHA-284x   |  1.01   | 284x-101.obj | bios1632.map | 64KB (512kBit)
+Controller | Version | patch object  | map file     | ROM chip size
+-----------|---------|---------------|--------------|---------------
+AHA-274x   | 2.11    | 274x-211.obj  | bios16k.map  | 32KB (256kBit)
+AHA-284x   | 1.01    | 284x-101.obj  | bios1632.map | 64KB (512kBit)
+AHA-284x   | 2.0     | 284x-20.obj   | bios1632.map | 64KB (512kBit)
 
 Furthermore, a patch for the following ASPI driver is included
 
@@ -24,12 +25,28 @@ Driver       | Version | patch object | map file   | file size
 ASPI7DOS.SYS | 1.42    | a7-142.obj   | a7-142.map | 36160 bytes
 
 Note that the latest 274x BIOS (2.11) seems to not be available for download from the Adaptec / MicroSemi. Their page has version 2.10. This patch *does not apply to version 2.10*. You can obtain the ROM image by reading it from an controller that has the latest version. The ROM chip is an OTP chip labelled `549306-00 D BIOS 7D00 (c) 1993`.
+The same applies to 284x - only BIOS version 1.01 is available on Adaptec site while controller may have version 2.0. Please note that BIOS version "downgrade" (even non-patched one) can cause problems in controller behavior and use the same or newer BIOS versions than you currently have.
 
 You can run `omfpatch 274x-211.bin bios16k.map 274x-211.obj` to create a patched BIOS image for the 2740.
-You can run `omfpatch 284x-101.bin bios1632.map 284x-101.obj` to create a patched BIOS image for the 2840.
+You can run `omfpatch 284x-101.bin bios1632.map 284x-101.obj` to create a patched BIOS image for the 2840 BIOS v1.01.
+You can run `omfpatch 284x-20.bin bios1632.map 284x-20.obj` to create a patched BIOS image for the 2840 BIOS v2.0.
 
 The patched BIOS identifies itself as "2.11 EDD 1.0" instead of just "2.11 Release" to indicate the *extended disk drive* specification.
 
+Patches for new BIOS versions
+-----------------------------
+
+If your BIOS version doesn't match any of the provided patches you can try creating your own patch by finding the corresponding offsets in your BIOS image. That's an example how 284x 2.00 patch was created:
+1. Create copy of asm file for similar controller model (for example 284x-201.asm).
+2. Get the data located within offset variable in known BIOS version, 4 bytes is enough.
+   `ResetLocalStateOfs  = 0C80h` - in version 1.01 of the BIOS you can find such values: `06 51 8A 46`
+3. Find the offset of these 4 bytes in your BIOS version - they should be not far from the original offset.
+   In BIOS v2.0 these files are located within offset `0CA8h` - 28h or 40dec bytes later.
+4. Replace the offset in your asm file with the value you just found.
+5. Repeat steps 2-4 for every variable, usually if you find the first offset "delta" every other will be the same or similar.
+
+To compile your new patch file use the command `jwasm -Zm 284x-201.asm`.
+
 Disclaimer
 ----------