loader/eckd-ipl-rec/eckd.s

   1 /*
   2  * Copyright (c) 2009-2011 Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a copy
   5  * of this software and associated documentation files (the "Software"), to deal
   6  * in the Software without restriction, including without limitation the rights
   7  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   8  * copies of the Software, and to permit persons to whom the Software is
   9  * furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  17  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  19  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  20  * SOFTWARE.
  21  */
  22
  23 # During the system IPL, 24 bytes are read from the device.
  24 #
  25 # NOTE: zArch IPLs in ESA/390 mode.
  26 #
  27
  28 .org 0
  29 .globl START
  30 START:
  31
  32 #
  33 # Bytes 0-7 contain PSW to be loaded after IO operation completes
  34 #
  35         .byte   0x00
  36                 #   bits  value   name                        desc
  37                 #      0      0   <zero>
  38                 #      1      0   PER Mask (R)                disabled
  39                 #    2-4      0   <zero>
  40                 #      5      0   DAT Mode (T)                disabled
  41                 #      6      0   I/O Mask (IO)               disabled
  42                 #      7      0   External Mask (EX)          disabled
  43
  44         .byte   0x08
  45                 #   bits  value   name                        desc
  46                 #   8-11      0   Key
  47                 #     12      1   <one>
  48                 #     13      0   Machine-Check Mask (M)      disabled
  49                 #     14      0   Wait State (W)              executing
  50                 #     15      0   Problem State (P)           supervisor state
  51
  52         .byte   0x00
  53                 #   bits  value   name                        desc
  54                 #  16-17      0   Address-Space Control (AS)  disabled
  55                 #  18-19      0   Condition Code (CC)
  56                 #  20-23      0   Program Mask                exceptions disabled
  57
  58         .byte   0x00
  59                 #   bits  value   name                        desc
  60                 #  24-30      0   <zero>
  61                 #     31      0   Extended Addressing (EA)    ! 64 mode
  62
  63         .byte   0x80    # bits 32-39
  64         .byte   0x80    # bits 40-47
  65         .byte   0x00    # bits 48-55
  66         .byte   0x00    # bits 56-63
  67                 #   bits  value   name                        desc
  68                 #     32      1   Basic Addressing (BA)       BA = 31, !BA = 24
  69                 #  33-63   addr   Instruction Address         Address to exec
  70
  71 #
  72 # The remaining 16 bytes should contain CCW to read data from device
  73 #
  74
  75 # CCW format-0:
  76 #   bits  name
  77 #    0-7  Cmd Code
  78 #   8-31  Data Address
  79 #     32  Chain-Data (CD)
  80 #     33  Chain-Command (CC)
  81 #     34  Sup.-Len.-Inditcation (SLI)
  82 #     35  Skip (SKP)
  83 #     36  Prog.-Contr.-Inter. (PCI)
  84 #     37  Indir.-Data-Addr. (IDA)
  85 #     38  Suspend (S)
  86 #     39  Modified I.D.A. (MIDA)
  87 #  40-47  <ignored>
  88 #  48-63  number of bytes to read
  89
  90 #
  91 # CCW 1 (bytes 8-15): format-0
  92 #
  93         # READ DATA 4 kB to 0x800000
  94         .byte   0x86, 0x80, 0x00, 0x00
  95         .byte   0x00, 0x00, 0x10, 0x00
  96
  97 #
  98 # CCW 2 (bytes 16-23): format-0
  99 #
 100         # invalid (unused)
 101         .byte   0x00, 0x00, 0x00, 0x00
 102         .byte   0x00, 0x00, 0x00, 0x00