Changeset 612 in xtideuniversalbios for trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs/AtaGeometry.asm

Timestamp:

May 26, 2021, 1:42:14 PM (3 years ago)

Author:

krille_n_

Message:

Changes:

• BIOSDRVS builds again (broken since r609). Also removed the last remnants of RESERVE_DIAGNOSTIC_CYLINDER from BIOSDRVS that I missed in r606.
• Put in a limit on the P-CHS cylinder count in an attempt to improve compatibility with some CF cards that violates the ATA specification. The limit applies only to the BIOS. BIOSDRVS will continue to show the true cylinder count since we might want to add code later to warn the user when encountering incompatible drives like these.
• Optimized the bug fix in r611.
• Updated the copyright notices in XTIDECFG and BIOSDRVS.

File:

• trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs/AtaGeometry.asm (modified) (3 diffs)

trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs/AtaGeometry.asm

@@ -84 +84 @@
     dec     dx                      ; Set ZF if TRANSLATEMODE_LARGE, SF if TRANSLATEMODE_NORMAL
     jns     SHORT .CheckIfLargeTranslationWanted
-    call    AH8h_LimitAXtoMaximumLCylinders ; TRANSLATEMODE_NORMAL maximum cylinders
+    call    AtaGeometry_LimitAXtoMaximumLCylinders  ; TRANSLATEMODE_NORMAL maximum cylinders
     inc     dx
 .CheckIfLargeTranslationWanted:
@@ -239 +239 @@
     mov     bl, [es:si+ATA1.wHeadCnt]   ; Heads (1...16)
     mov     bh, [es:si+ATA1.wSPT]       ; Sectors per Track (1...63)
+%ifndef EXCLUDE_FROM_BIOSDRVS   ; We want the true value in BIOSDRVS
+    ; Some CF cards (for example Sandisk Ultra 16/32 GB) violates
+    ; the ATA specification by reporting more than 16383 cylinders.
+    MIN_U   ax, MAX_PCHS_CYLINDERS      ; Limit the count to avoid problems.
+%endif
     ret
 
@@ -360 +365 @@
     ret
 
+
+;--------------------------------------------------------------------
+; AtaGeometry_LimitAXtoMaximumLCylinders
+;   Parameters:
+;       AX:     Number of total L-CHS cylinders (1...1027)
+;   Returns:
+;       AX:     Number of usable L-CHS cylinders (1...1024)
+;   Corrupts registers:
+;       Nothing
+;--------------------------------------------------------------------
+AtaGeometry_LimitAXtoMaximumLCylinders:
+    MIN_U   ax, MAX_LCHS_CYLINDERS
+    ret
+