source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/Initialization/AdvAtaInit.asm@ 385

; Project name  :   XTIDE Universal BIOS
; Description   :   Common functions for initializing different
;                   VLB and PCI IDE Controllers.

;
; XTIDE Universal BIOS and Associated Tools 
; Copyright (C) 2009-2010 by Tomi Tilli, 2011-2012 by XTIDE Universal BIOS Team.
;
; This program is free software; you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation; either version 2 of the License, or
; (at your option) any later version.
; 
; This program is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
; GNU General Public License for more details.      
; Visit http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
;       

; Section containing code
SECTION .text

;--------------------------------------------------------------------
; AdvAtaInit_DetectControllerForIdeBaseInBX
;   Parameters:
;       BX:     IDE Controller base port
;   Returns:
;       AX:     ID WORD specific for detected controller
;               Zero if no controller detected
;       DX:     Controller base port (not IDE)
;       CF:     Set if controller detected
;               Cleared if no controller
;   Corrupts registers:
;       BX
;--------------------------------------------------------------------
AdvAtaInit_DetectControllerForIdeBaseInBX:
    call    Vision_DetectAndReturnIDinAXandPortInDXifControllerPresent
    jne     SHORT .NoAdvancedControllerForPortBX
    call    Vision_DoesIdePortInBXbelongToControllerWithIDinAX
    jne     SHORT .NoAdvancedControllerForPortBX

    stc     ; Advanced Controller found for port BX
    ret

.NoAdvancedControllerForPortBX:
    xor     ax, ax
    ret


;--------------------------------------------------------------------
; AdvAtaInit_GetControllerMaxPioModeToAL
;   Parameters:
;       AX:     ID WORD specific for detected controller
;   Returns:
;       AL:     Max supported PIO mode
;       AH:     FLGH_DPT_IORDY if IORDY supported, zero otherwise
;       CF:     Set if PIO limit necessary
;               Cleared if no need to limit timings
;   Corrupts registers:
;       (AX if CF cleared)
;--------------------------------------------------------------------
AdvAtaInit_GetControllerMaxPioModeToAL  equ Vision_GetMaxPioModeToAL


;--------------------------------------------------------------------
; AdvAtaInit_InitializeControllerForDPTinDSDI
;   Parameters:
;       DS:DI:  Ptr to DPT for Single or Slave Drive
;   Returns:
;       CF:     Cleared if success or no controller to initialize
;               Set if error
;   Corrupts registers:
;       AX, BX, CX, DX
;--------------------------------------------------------------------
AdvAtaInit_InitializeControllerForDPTinDSDI:
    push    bp
    push    si

    ; Call Controller Specific initialization function
    mov     ax, [di+DPT_ADVANCED_ATA.wControllerID]
    test    ax, ax
    jz      SHORT .NoAdvancedController ; Return with CF cleared

    ; We only support Vision at the moment so no need to identify ID
    call    AdvAtaInit_LoadMasterDPTtoDSSIifSlaveInDSDI
    call    Vision_InitializeWithIDinAHandConfigInAL

.NoAdvancedController:
    pop     si
    pop     bp
    ret


;--------------------------------------------------------------------
; AdvAtaInit_LoadMasterDPTtoDSSIifSlaveInDSDI
;   Parameters:
;       DS:DI:  Ptr to DPT for Single or Slave Drive
;   Returns:
;       DS:DI:  Ptr to DPT for Single or Slave Drive
;       SI:     Offset to Master DPT if Slave Drive present
;               Zero if Slave Drive not present
;   Corrupts registers:
;       AX
;--------------------------------------------------------------------
AdvAtaInit_LoadMasterDPTtoDSSIifSlaveInDSDI:
    ; Must be Slave Drive if previous DPT has same IDEVARS offset
    lea     si, [di-LARGEST_DPT_SIZE]   ; DS:SI points to previous DPT
    mov     al, [di+DPT.bIdevarsOffset]
    cmp     al, [si+DPT.bIdevarsOffset]
    je      SHORT .MasterAndSlaveDrivePresent

    ; We only have single drive so zero SI
    xor     si, si
.MasterAndSlaveDrivePresent:
    ret


;--------------------------------------------------------------------
; AdvAtaInit_SelectSlowestCommonPioTimingsToBXandCXfromDSSIandDSDI
;   Parameters:
;       DS:DI:  Ptr to DPT for Single or Slave Drive
;       SI:     Offset to Master DPT if Slave Drive present
;               Zero if Slave Drive not present
;   Returns:
;       BX:     Best common PIO mode
;       CX:     Slowest common PIO Cycle Time in nanosecs
;   Corrupts registers:
;       Nothing
;--------------------------------------------------------------------
AdvAtaInit_SelectSlowestCommonPioTimingsToBXandCXfromDSSIandDSDI:
    eMOVZX  bx, [di+DPT_ADVANCED_ATA.bPioMode]
    mov     cx, [di+DPT_ADVANCED_ATA.wMinPioCycleTime]
    test    si, si
    jz      SHORT .PioTimingsLoadedToAXandCX
    MIN_U   bl, [si+DPT_ADVANCED_ATA.bPioMode]
    MAX_U   cx, [si+DPT_ADVANCED_ATA.wMinPioCycleTime]
.PioTimingsLoadedToAXandCX:
    ret