• peter fuerst's avatar
    [SCSI] wd33c93: Fast SCSI with WD33C93B · a5d8421b
    peter fuerst authored
    Attached are patches, which help to utilize more of the WD33C93B SCSI
    controller's capabilities.
    
    1) Added/changed all the necessary code to enable Burst Mode DMA. Only
       Single Byte DMA was used before.
    
    2) Added/changed all the necessary code to enable Fast-10 SCSI transfers.
    
    3) The original driver inadvertently used a transfer period of 1000-800ns
       (the lowest possible transfer rate) for asynchronous data transfers,
       instead of the (configurable) default period intended for this purpose,
       if the target responded to a SDTR not with a Reject-message, but with
       a zero-SDTR. This issue was fixed.
       Moreover, in case of a Reject the driver used the default-period's
       initialization-value instead of its (maybe smaller) current value. The
       missing assignment was added.
    
    4) The driver's commandline- and proc-file-interface was augmented to
       handle the new options properly.
    
    The WD33C93 manual, found at
    http://www.datasheet.in/datasheet-html/W/D/3/WD33C93B_WesternDigital.pdf.html,
    was very helpful.
    Signed-off-by: default avatarpeter fuerst <post@pfrst.de>
    Signed-off-by: default avatarJames Bottomley <James.Bottomley@SteelEye.com>
    a5d8421b
wd33c93.h 11 KB