losp/x86-pc/ata.lisp

   1 ;;;; Movitz ATA Hard Drive Driver
   2 ;;;; --------------------------------------------------------------------------
   3 ;;;; [13 Mar 2008]  Martin Bealby
   4 ;;;;   Moved into muerte.x86-pc.ata package
   5 ;;;;   'ata' prefix removed from function names
   6 ;;;; [23 Feb 2008]  Martin Bealby
   7 ;;;;   Partition reading and parsing functions added
   8 ;;;;   Read / write sector functions converted to work with lists of bytes
   9 ;;;; [25 Oct 2007]  Martin Bealby
  10 ;;;;   Rewritten from scratch based on http://www.osdever.net/tutorials/lba.php
  11 ;;;; --------------------------------------------------------------------------
  12
  13
  14 ;;;; --------------------------------------------------------------------------
  15 ;;;; Package Setup
  16 ;;;; --------------------------------------------------------------------------
  17 (require :x86-pc/package)
  18
  19 (defpackage muerte.x86-pc.ata
  20   (:use muerte.cl muerte.lib muerte)
  21   (:export #:read-partition-table
  22                    #:get-partition-data
  23                    #:partition-active-p
  24                    #:partition-type
  25                    #:partition-start-offset
  26                    #:partition-size
  27                    #:lba-read-sector
  28                    #:lba-write-sector))
  29
  30 (provide :x86-pc/ata)
  31
  32 (in-package muerte.x86-pc.ata)
  33
  34
  35 ;;;; --------------------------------------------------------------------------
  36 ;;;; Constants
  37 ;;;; --------------------------------------------------------------------------
  38 (defconstant +controller0+ #x1F0)
  39 (defconstant +controller1+ #x170)
  40
  41 (defconstant +offset-data+ 0)
  42 (defconstant +offset-error-precomp+ 1)
  43 (defconstant +offset-sector-count+ 2)
  44 (defconstant +offset-lba1+ 3)
  45 (defconstant +offset-lba2+ 4)
  46 (defconstant +offset-lba3+ 5)
  47 (defconstant +offset-drive-head+ 6)
  48 (defconstant +offset-status-command+ 7)
  49
  50
  51 (defconstant +command-read+ #x20)
  52 (defconstant +command-write+ #x30)
  53 (defconstant +bitflag-busy+ 7)
  54
  55
  56 (defparameter *partitions* '((nil nil nil nil) ; controller 1 disc 1
  57                                                                  (nil nil nil nil) ; controller 1 disc 2
  58                                                                  (nil nil nil nil) ; controller 2 disc 1
  59                                                                  (nil nil nil nil))) ; controller 2 disc 2
  60
  61
  62 ;;;; --------------------------------------------------------------------------
  63 ;;;; Drive Functions
  64 ;;;; --------------------------------------------------------------------------
  65 (defun busy-wait (controller)
  66   "ATA Driver busy spin loop."
  67   (loop while (logbitp +bitflag-busy+
  68                                            (io-port (+ controller
  69                                                                    +offset-status-command+)
  70                                                                 :unsigned-byte8))))
  71
  72 (defun send-command (controller command)
  73   "Send a command to an IDE controller."
  74   (setf (io-port (+ controller +offset-status-command+) :unsigned-byte8)
  75                 command))
  76
  77 (defun lba-read-write-common (controller drive-number block-address)
  78   (if (= 0 block-address)
  79           (error "Sector zero is not a valid index for LBA addressing."))
  80   ;; send a null
  81   (setf (io-port (+ controller
  82                                         +offset-error-precomp+) :unsigned-byte8) 0)
  83   ;; send a sector count
  84   (setf (io-port (+ controller
  85                                         +offset-sector-count+):unsigned-byte8) 1)
  86   ;; send the lowest 8 bits of the lba
  87   (setf (io-port (+ controller +offset-lba1+) :unsigned-byte8)
  88                 (logand block-address #xFF))
  89   ;; send the next 8 bits
  90   (setf (io-port (+ controller +offset-lba2+) :unsigned-byte8)
  91                 (ash (logand block-address #xFF00)
  92                          -8))
  93   ;; send the next 8 bits
  94   (setf (io-port (+ controller +offset-lba3+) :unsigned-byte8)
  95                 (ash (logand block-address #xFF0000)
  96                          -16))
  97   ;; send the last 4 bits and some magic bits
  98   (setf (io-port (+ controller +offset-drive-head+) :unsigned-byte8)
  99                 (logand
 100                  (logior (ash (logand block-address #xF000000)
 101                                           -24)
 102                                  #xE0  ;; magic
 103                                  (ash drive-number 4))
 104                  #x0F)))
 105
 106
 107 (defun lba-read-sector (controller drive-number block-address)
 108   "Reads a specified sector of data from the disk."
 109   ;; Call common initialisation
 110   (lba-read-write-common controller drive-number block-address)
 111   ;; send read command
 112   (send-command controller +command-read+)
 113   ;; wait for the drive
 114   (busy-wait controller)
 115   ;; read the data
 116   (loop for position from 0 to 255
 117          for data = (io-port (+ controller +offset-data+)
 118                                                    :unsigned-byte16)
 119      collect (logand #x00FF data)
 120          collect (ash (logand #xFF00 data) -8)))
 121
 122
 123 (defun lba-write-sector (controller drive-number block-address data)
 124   "Writes data to a sector of the disk."
 125   ;; data must be a list of 512 unsigned-byte8's
 126   ;; based upon lba-read-sector-above
 127   (lba-read-write-common controller drive-number block-address)
 128   (send-command controller +command-write+)
 129   (busy-wait controller)
 130   (loop for position from 0 to 511 by 2
 131          do (setf (io-port (+ controller +offset-data+) :unsigned-byte16)
 132                           (+ (ash (nth position data) 8)
 133                                  (nth (+ 1 position) data)))))
 134
 135
 136 ;;;; --------------------------------------------------------------------------
 137 ;;;; Partition Functions
 138 ;;;; --------------------------------------------------------------------------
 139 (defun read-partition-table (controller drive-number)
 140   "Reads and stores the partition table from the specified disk."
 141   (cond ((> controller 1)                       ; assume 2 controllers for now
 142                  (error "Invalid controller number.")))
 143   (cond ((> drive-number 1)                             ; assume 2 drives per controller for now
 144                  (error "Invalid driver number.")))
 145
 146   (let ((sector
 147                   (cond ((= 0 controller)
 148                                  (lba-read-sector +controller0+ drive-number 1))
 149                                 ((= 1 controller)
 150                                  (lba-read-sector +controller1+ drive-number 1)))))
 151         (setf (nth (+ controller drive-number) *partitions*)
 152                   (list (loop for offset from 446 to 461
 153                                    collect (nth offset sector))
 154                                 (loop for offset from 462 to 477
 155                                    collect (nth offset sector))
 156                                 (loop for offset from 478 to 493
 157                                    collect (nth offset sector))
 158                                 (loop for offset from 494 to 509
 159                                    collect (nth offset sector))))))
 160
 161 (defun get-partition-data (controller drive-number partition)
 162   "Returns the partition data for the specified controller and drive from the local cache.
 163    The data can be supplied to:
 164       partition-active-p
 165       partition-type
 166       partition-start-offset
 167       partition-size"
 168   (cond ((> controller 1)                       ; assume 2 controllers for now
 169                  (error "Invalid controller number.")))
 170   (cond ((> drive-number 1)                             ; assume 2 drives per controller for now
 171                  (error "Invalid driver number.")))
 172   (cond ((> partition 3)                                ; max 4 partitions per drive (no extended partitions for now)
 173                  (error "Invalid partition number.")))
 174   (nth partition
 175            (nth (+ controller drive-number) *partitions*)))
 176
 177 (defun partition-active-p (partition-data)
 178   "Returns the state of the active flag for the partition."
 179   (cond ((= #x80 (nth 0 partition-data))
 180                  t)
 181                 (t nil)))
 182
 183 (defun partition-type (partition-data)
 184   "Returns the partition type for the partition."
 185   (let ((id (nth 4 partition-data)))
 186         (cond ((= #x00 id)
 187                    "EMPTY")
 188                   ((= #x06 id)
 189                    "FAT16")
 190                   ((= #x07 id)
 191                    "NTFS")
 192                   ((= #x0b id)
 193                    "FAT32")
 194                   ((= #x0c id)
 195                    "FAT32-LBA")
 196                   ((= #x0e id)
 197                    "FAT16-LBA")
 198                   ((= #x82 id)
 199                    "LINUX-SWAP")
 200                   ((= #x83 id)
 201                    "LINUX")
 202                   ((= #xA5 id)
 203                    "FREEBSD")
 204                   ((= #xA6 id)
 205                    "OPENBSD")
 206                   ((= #xA9 id)
 207                    "NETBSD")
 208                   ((= #xE8 id)
 209                    "LUKS")
 210                   (t
 211                    "UNKNOWN"))))
 212
 213 (defun partition-start-offset (partition-data)
 214   "Returns the starting offset (LBA) for the partition."
 215   (+ (nth 8 partition-data)
 216          (ash (nth 9 partition-data)
 217                   8)
 218          (ash (nth 10 partition-data)
 219                   16)
 220          (ash (nth 11 partition-data)
 221                   24)))
 222
 223 (defun partition-size (partition-data)
 224   "Returns the size of the partition."
 225   (+ (nth 12 partition-data)
 226          (ash (nth 13 partition-data)
 227                   8)
 228          (ash (nth 14 partition-data)
 229                   16)
 230          (ash (nth 15 partition-data)
 231                   24)))
 232