source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/Device/IDE/IdeCommand.asm@ 291

; Project name  :   XTIDE Universal BIOS
; Description   :   IDE Device Command functions.

; Section containing code
SECTION .text

;--------------------------------------------------------------------
; IdeCommand_ResetMasterAndSlaveController
;   Parameters:
;       DS:DI:  Ptr to DPT (in RAMVARS segment)
;   Returns:
;       AH:     INT 13h Error Code
;       CF:     Cleared if success, Set if error
;   Corrupts registers:
;       AL, BX, CX, DX
;--------------------------------------------------------------------
IDEDEVICE%+Command_ResetMasterAndSlaveController:
    ; HSR0: Set_SRST
    call    AccessDPT_GetDeviceControlByteToAL
    or      al, FLG_DEVCONTROL_SRST | FLG_DEVCONTROL_nIEN   ; Set Reset bit
    OUTPUT_AL_TO_IDE_CONTROL_BLOCK_REGISTER     DEVICE_CONTROL_REGISTER_out
    mov     ax, HSR0_RESET_WAIT_US
    call    Timer_DelayMicrosecondsFromAX

    ; HSR1: Clear_wait
    call    AccessDPT_GetDeviceControlByteToAL
    or      al, FLG_DEVCONTROL_nIEN
    and     al, ~FLG_DEVCONTROL_SRST                        ; Clear reset bit
    OUTPUT_AL_TO_IDE_CONTROL_BLOCK_REGISTER     DEVICE_CONTROL_REGISTER_out
    mov     ax, HSR1_RESET_WAIT_US
    call    Timer_DelayMicrosecondsFromAX

    ; HSR2: Check_status
    mov     bx, TIMEOUT_AND_STATUS_TO_WAIT(TIMEOUT_MOTOR_STARTUP, FLG_STATUS_BSY)
    jmp     IDEDEVICE%+Wait_PollStatusFlagInBLwithTimeoutInBH


;--------------------------------------------------------------------
; IdeCommand_IdentifyDeviceToBufferInESSIwithDriveSelectByteInBH
;   Parameters:
;       BH:     Drive Select byte for Drive and Head Select Register
;       DS:     Segment to RAMVARS
;       ES:SI:  Ptr to buffer to receive 512-byte IDE Information
;       CS:BP:  Ptr to IDEVARS
;   Returns:
;       AH:     INT 13h Error Code
;       CF:     Cleared if success, Set if error
;   Corrupts registers:
;       AL, BL, CX, DX, SI, DI, ES
;--------------------------------------------------------------------
IDEDEVICE%+Command_IdentifyDeviceToBufferInESSIwithDriveSelectByteInBH:
    ; Create fake DPT to be able to use Device.asm functions
    call    FindDPT_ForNewDriveToDSDI
    eMOVZX  ax, bh
    mov     [di+DPT.wFlags], ax
    mov     [di+DPT.bIdevarsOffset], bp
    mov     BYTE [di+DPT_ATA.bSetBlock], 1  ; Block = 1 sector
%ifdef ASSEMBLE_SHARED_IDE_DEVICE_FUNCTIONS
    call    IdeDPT_StoreReversedAddressLinesFlagIfNecessary
%endif

    ; Wait until drive motors have reached max speed
    cmp     bp, BYTE ROMVARS.ideVars0
    jne     SHORT .SkipLongWaitSinceDriveIsNotPrimaryMaster
    test    al, FLG_DRVNHEAD_DRV
    jnz     SHORT .SkipLongWaitSinceDriveIsNotPrimaryMaster
    mov     bx, TIMEOUT_AND_STATUS_TO_WAIT(TIMEOUT_MOTOR_STARTUP, FLG_STATUS_BSY)
    call    IDEDEVICE%+Wait_PollStatusFlagInBLwithTimeoutInBH
.SkipLongWaitSinceDriveIsNotPrimaryMaster:

    ; Create IDEPACK without INTPACK
    push    bp
    call    Idepack_FakeToSSBP

    ; Prepare to output Identify Device command
    mov     dl, 1                       ; Sector count (required by IdeTransfer.asm)
    mov     al, COMMAND_IDENTIFY_DEVICE
    mov     bx, TIMEOUT_AND_STATUS_TO_WAIT(TIMEOUT_IDENTIFY_DEVICE, FLG_STATUS_DRQ)
    call    Idepack_StoreNonExtParametersAndIssueCommandFromAL

    ; Clean stack and return
    lea     sp, [bp+EXTRA_BYTES_FOR_INTPACK]    ; This assumes BP hasn't changed between Idepack_FakeToSSBP and here
    pop     bp
    ret


;--------------------------------------------------------------------
; IdeCommand_OutputWithParameters
;   Parameters:
;       BH:     System timer ticks for timeout
;       BL:     IDE Status Register bit to poll after command
;       ES:SI:  Ptr to buffer (for data transfer commands)
;       DS:DI:  Ptr to DPT (in RAMVARS segment)
;       SS:BP:  Ptr to IDEPACK
;   Returns:
;       AH:     INT 13h Error Code
;       CX:     Number of successfully transferred sectors (for transfer commands)
;       CF:     Cleared if success, Set if error
;   Corrupts registers:
;       AL, BX, (CX), DX, (ES:SI for data transfer commands)
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
IDEDEVICE%+Command_OutputWithParameters:
    push    bx                      ; Store status register bits to poll

    ; Select Master or Slave drive and output head number or LBA28 top bits
    call    IDEDEVICE%+Command_SelectDrive
    jc      SHORT .DriveNotReady

    ; Output Device Control Byte to enable or disable interrupts
    mov     al, [bp+IDEPACK.bDeviceControl]
%ifdef ASSEMBLE_SHARED_IDE_DEVICE_FUNCTIONS ; JR-IDE/ISA
    test    al, FLG_DEVCONTROL_nIEN ; Interrupts disabled?
    jnz     SHORT .DoNotSetInterruptInServiceFlag

    ; Clear Task Flag and set Interrupt In-Service Flag
    or      BYTE [di+DPT.bFlagsHigh], FLGH_DPT_INTERRUPT_IN_SERVICE
    push    ds
    LOAD_BDA_SEGMENT_TO ds, dx, !   ; Also zero DX
    mov     [BDA.bHDTaskFlg], dl
    pop     ds
.DoNotSetInterruptInServiceFlag:
%endif
    OUTPUT_AL_TO_IDE_CONTROL_BLOCK_REGISTER     DEVICE_CONTROL_REGISTER_out

    ; Output Feature Number
    mov     al, [bp+IDEPACK.bFeatures]
    OUTPUT_AL_TO_IDE_REGISTER   FEATURES_REGISTER_out

    ; Output Sector Address High (only used by LBA48)
%ifdef MODULE_EBIOS
    eMOVZX  ax, BYTE [bp+IDEPACK.bLbaLowExt]    ; Zero sector count
    mov     cx, [bp+IDEPACK.wLbaMiddleAndHighExt]
    call    IDEDEVICE%+OutputSectorCountAndAddress
%endif

    ; Output Sector Address Low
    mov     ax, [bp+IDEPACK.wSectorCountAndLbaLow]
    mov     cx, [bp+IDEPACK.wLbaMiddleAndHigh]
    call    IDEDEVICE%+OutputSectorCountAndAddress

    ; Output command
    mov     al, [bp+IDEPACK.bCommand]
    OUTPUT_AL_TO_IDE_REGISTER   COMMAND_REGISTER_out

    ; Wait until command completed
    pop     bx                      ; Pop status and timeout for polling
    cmp     bl, FLG_STATUS_DRQ      ; Data transfer started?
    je      SHORT IDEDEVICE%+Transfer_StartWithCommandInAL
    test    BYTE [bp+IDEPACK.bDeviceControl], FLG_DEVCONTROL_nIEN
    jz      SHORT .WaitForIrqOrRdy
    jmp     IDEDEVICE%+Wait_PollStatusFlagInBLwithTimeoutInBH

ALIGN JUMP_ALIGN
.WaitForIrqOrRdy:
    jmp     IDEDEVICE%+Wait_IRQorStatusFlagInBLwithTimeoutInBH

.DriveNotReady:
    pop     bx                          ; Clean stack
    ret


;--------------------------------------------------------------------
; IdeCommand_SelectDrive
;   Parameters:
;       DS:DI:  Ptr to DPT (in RAMVARS segment)
;       SS:BP:  Ptr to IDEPACK
;   Returns:
;       AH:     INT 13h Error Code
;       CF:     Cleared if success, Set if error
;   Corrupts registers:
;       AL, BX, CX, DX
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
IDEDEVICE%+Command_SelectDrive:
    ; Wait until neither Master or Slave Drive is busy.
    ; I don't think this wait is necessary.
    ;mov        bx, TIMEOUT_AND_STATUS_TO_WAIT(TIMEOUT_BSY, FLG_STATUS_BSY)
    ;cmp        BYTE [bp+IDEPACK.bCommand], COMMAND_IDENTIFY_DEVICE
    ;eCMOVE bh, TIMEOUT_IDENTIFY_DEVICE
    ;call   IDEDEVICE%+Wait_PollStatusFlagInBLwithTimeoutInBH

    ; Select Master or Slave Drive
    mov     al, [bp+IDEPACK.bDrvAndHead]
    OUTPUT_AL_TO_IDE_REGISTER   DRIVE_AND_HEAD_SELECT_REGISTER
    mov     bx, TIMEOUT_AND_STATUS_TO_WAIT(TIMEOUT_DRDY, FLG_STATUS_DRDY)
    cmp     BYTE [bp+IDEPACK.bCommand], COMMAND_IDENTIFY_DEVICE
    eCMOVE  bh, TIMEOUT_IDENTIFY_DEVICE
    call    IDEDEVICE%+Wait_PollStatusFlagInBLwithTimeoutInBH

    ; Ignore errors from IDE Error Register (set by previous command)
    cmp     ah, RET_HD_TIMEOUT
    je      SHORT .FailedToSelectDrive
    xor     ax, ax                  ; Always success unless timeout
    ret
.FailedToSelectDrive:
    stc
    ret


;--------------------------------------------------------------------
; OutputSectorCountAndAddress
;   Parameters:
;       AH:     LBA low bits (Sector Number)
;       AL:     Sector Count
;       CL:     LBA middle bits (Cylinder Number low)
;       CH:     LBA high bits (Cylinder Number high)
;       DS:DI:  Ptr to DPT (in RAMVARS segment)
;   Returns:
;       Nothing
;   Corrupts registers:
;       AL, BX, DX
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
IDEDEVICE%+OutputSectorCountAndAddress:
    OUTPUT_AL_TO_IDE_REGISTER   SECTOR_COUNT_REGISTER

    mov     al, ah
    OUTPUT_AL_TO_IDE_REGISTER   LBA_LOW_REGISTER

    mov     al, cl
    OUTPUT_AL_TO_IDE_REGISTER   LBA_MIDDLE_REGISTER

    mov     al, ch
    JUMP_TO_OUTPUT_AL_TO_IDE_REGISTER   LBA_HIGH_REGISTER