Ignore:
Timestamp:
Jun 23, 2013, 3:52:31 PM (11 years ago)
Author:
krille_n_@…
google:author:
krille_n_@hotmail.com
Message:

Changes:

  • Building the BIOS Drive Information Tool now works again.
  • Moved all XT-CF related code to MODULE_8BIT_IDE_ADVANCED. I don't see how an XT-CF card could work without *_ADVANCED anyway but if I'm wrong, feel free to undo this. Note! The autodetection code in XTIDECFG has NOT been changed to reflect this (still relies on MODULE_8BIT_IDE).
  • Optimizations and fixes in general.
File:
1 edited

Legend:

Unmodified
Added
Removed
  • trunk/XTIDE_Universal_BIOS/Src/Device/IDE/IdeDmaBlock.asm

    r551 r558  
    11; Project name  :   XTIDE Universal BIOS
    2 ; Description   :   IDE Read/Write functions for transferring
    3 ;           block using DMA.
    4 ;           These functions should only be called from IdeTransfer.asm.
     2; Description   :   IDE Read/Write functions for transferring block using DMA.
     3;                   These functions should only be called from IdeTransfer.asm.
     4
    55; Modified JJP 05-Jun-13
     6
    67;
    78; XTIDE Universal BIOS and Associated Tools
     
    8485    shl     cx, 9                                   ; CX = Block size in BYTEs
    8586%else
    86     xchg        cl, ch
     87    xchg    cl, ch
    8788    shl     cx, 1
    8889%endif
     
    9293    neg     ax          ; 2s compliment
    9394
    94     ; if DI was zero carry flag will be cleared (and set otherwise)
     95    ; If DI was zero carry flag will be cleared (and set otherwise)
    9596    ; When DI is zero only one transfer is required since we've limited the
    9697    ; XT-CFv3 block size to 32k
    97     jnc .TransferLastDmaPageWithSizeInCX
     98    jnc     SHORT .TransferLastDmaPageWithSizeInCX
    9899
    99100    ; CF was set, so DI != 0 and we might need one or two transfers
    100101    cmp     cx, ax                                  ; if we won't cross a physical page boundary...
    101     jbe SHORT .TransferLastDmaPageWithSizeInCX  ; ...perform the transfer in one operation
     102    jbe     SHORT .TransferLastDmaPageWithSizeInCX  ; ...perform the transfer in one operation
    102103
    103104    ; Calculate how much we can transfer on first and second rounds
    104     xchg        cx, ax          ; CX = BYTEs for first page
    105     sub     ax, cx          ; AX = BYTEs for second page
    106     push        ax          ; Save bytes for second transfer on stack
     105    xchg    cx, ax      ; CX = BYTEs for first page
     106    sub     ax, cx      ; AX = BYTEs for second page
     107    push    ax          ; Save bytes for second transfer on stack
    107108
    108109    ; Transfer first DMA page
     
    126127;       ES:DI updated (CX is added)
    127128;   Corrupts registers:
    128 ;       AX
     129;       AX, CX
    129130;--------------------------------------------------------------------
    130131ALIGN JUMP_ALIGN
     
    161162    sti                                                         ; Enable interrupts
    162163
     164    ; Update physical address in ES:DI - since IO might need several calls through this function either from here
     165    ; if crossing a physical page boundary, or from IdeTransfer.asm if requested sectors was > PIOVARS.wSectorsInBlock
     166    ; We update the pointer here (before the actual transfer) to avoid having to save the byte count on the stack
     167    mov     ax, es                      ; copy physical page address to ax
     168    add     di, cx                      ; add requested bytes to di
     169    adc     al, 0                       ; and increment physical page address, if required
     170    mov     es, ax                      ; and save it back in es
     171
    163172    ; XT-CF transfers 16 bytes at a time. We need to manually start transfer for every block by writing (anything)
    164173    ; to the XT-CFv3 Control Register, which raises DRQ thereby passing system control to the 8237 DMA controller.
     
    169178
    170179%if 0   ; Slow DMA code - works by checking 8237 status register after each 16-byte transfer, until it reports TC has been raised.
    171 ;ALIGN JUMP_ALIGN
    172 ;.TransferNextBlock:
    173 ;   cli                                 ; We want no ISR to read DMA Status Register before we do
    174 ;   out     dx, al                      ; Transfer up to 16 bytes to/from XT-CF card
    175 ;   in      al, STATUS_REGISTER_DMA8_in
    176 ;   sti
    177 ;   test    al, FLG_CH3_HAS_REACHED_TERMINAL_COUNT
    178 ;   jz      SHORT .TransferNextBlock    ; All bytes transferred?
    179 %endif ; Slow DMA code
    180 
    181 %if 1   ; Fast DMA code - perform computed number of transfers, then check DMA status register to be sure
    182     push    cx                          ; need byte count to update pointer at the end
     180ALIGN JUMP_ALIGN
     181.TransferNextBlock:
     182    cli                                 ; We want no ISR to read DMA Status Register before we do
     183    out     dx, al                      ; Transfer up to 16 bytes to/from XT-CF card
     184    in      al, STATUS_REGISTER_DMA8_in
     185    sti
     186    test    al, FLG_CH3_HAS_REACHED_TERMINAL_COUNT
     187    jz      SHORT .TransferNextBlock    ; All bytes transferred?
     188%else   ; Fast DMA code - perform computed number of transfers, then check DMA status register to be sure
    183189    add     cx, BYTE 15                 ; We'll divide transfers in 16-byte atomic transfers,
    184190    eSHR_IM cx, 4                       ; so include any partial block, which will be terminated
     
    191197    test    al, FLG_CH3_HAS_REACHED_TERMINAL_COUNT  ; ... for channel 3 terminal count
    192198    jz      SHORT .TransferNextDmaBlock ; If not set, get more bytes
    193     pop     cx                          ; get back requested bytes
    194 %endif ; Fast DMA code
    195 
    196     ; Update physical address in ES:DI - since IO might need several calls through this function either from here
    197     ; if crossing a physical page boundary, and from IdeTransfer.asm if requested sectors was > PIOVARS.wSectorsInBlock
    198     mov     ax, es                      ; copy physical page address to ax
    199     add     di, cx                      ; add requested bytes to di
    200     adc     al, 0                       ; and increment physical page address, if required
    201     mov     es, ax                      ; and save it back in es
     199%endif
    202200
    203201    ret
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