LXR qemu/pc-bios/s390-ccw/main.c

   1/*
   2 * S390 virtio-ccw loading program
   3 *
   4 * Copyright (c) 2013 Alexander Graf <agraf@suse.de>
   5 *
   6 * This work is licensed under the terms of the GNU GPL, version 2 or (at
   7 * your option) any later version. See the COPYING file in the top-level
   8 * directory.
   9 */
  10
  11#include "libc.h"
  12#include "s390-ccw.h"
  13#include "virtio.h"
  14
  15char stack[PAGE_SIZE * 8] __attribute__((__aligned__(PAGE_SIZE)));
  16static SubChannelId blk_schid = { .one = 1 };
  17IplParameterBlock iplb __attribute__((__aligned__(PAGE_SIZE)));
  18static char loadparm_str[LOADPARM_LEN + 1] = { 0, 0, 0, 0, 0, 0, 0, 0, 0 };
  19QemuIplParameters qipl;
  20
  21#define LOADPARM_PROMPT "PROMPT  "
  22#define LOADPARM_EMPTY  "        "
  23#define BOOT_MENU_FLAG_MASK (QIPL_FLAG_BM_OPTS_CMD | QIPL_FLAG_BM_OPTS_ZIPL)
  24
  25/*
  26 * Priniciples of Operations (SA22-7832-09) chapter 17 requires that
  27 * a subsystem-identification is at 184-187 and bytes 188-191 are zero
  28 * after list-directed-IPL and ccw-IPL.
  29 */
  30void write_subsystem_identification(void)
  31{
  32    SubChannelId *schid = (SubChannelId *) 184;
  33    uint32_t *zeroes = (uint32_t *) 188;
  34
  35    *schid = blk_schid;
  36    *zeroes = 0;
  37}
  38
  39void panic(const char *string)
  40{
  41    sclp_print(string);
  42    disabled_wait();
  43    while (1) { }
  44}
  45
  46unsigned int get_loadparm_index(void)
  47{
  48    return atoui(loadparm_str);
  49}
  50
  51static bool find_dev(Schib *schib, int dev_no)
  52{
  53    int i, r;
  54
  55    for (i = 0; i < 0x10000; i++) {
  56        blk_schid.sch_no = i;
  57        r = stsch_err(blk_schid, schib);
  58        if ((r == 3) || (r == -EIO)) {
  59            break;
  60        }
  61        if (!schib->pmcw.dnv) {
  62            continue;
  63        }
  64        if (!virtio_is_supported(blk_schid)) {
  65            continue;
  66        }
  67        /* Skip net devices since no IPLB is created and therefore no
  68         * no network bootloader has been loaded
  69         */
  70        if (virtio_get_device_type() == VIRTIO_ID_NET && dev_no < 0) {
  71            continue;
  72        }
  73        if ((dev_no < 0) || (schib->pmcw.dev == dev_no)) {
  74            return true;
  75        }
  76    }
  77
  78    return false;
  79}
  80
  81static void menu_setup(void)
  82{
  83    if (memcmp(loadparm_str, LOADPARM_PROMPT, LOADPARM_LEN) == 0) {
  84        menu_set_parms(QIPL_FLAG_BM_OPTS_CMD, 0);
  85        return;
  86    }
  87
  88    /* If loadparm was set to any other value, then do not enable menu */
  89    if (memcmp(loadparm_str, LOADPARM_EMPTY, LOADPARM_LEN) != 0) {
  90        return;
  91    }
  92
  93    switch (iplb.pbt) {
  94    case S390_IPL_TYPE_CCW:
  95    case S390_IPL_TYPE_QEMU_SCSI:
  96        menu_set_parms(qipl.qipl_flags & BOOT_MENU_FLAG_MASK,
  97                       qipl.boot_menu_timeout);
  98        return;
  99    }
 100}
 101
 102static void virtio_setup(void)
 103{
 104    Schib schib;
 105    int ssid;
 106    bool found = false;
 107    uint16_t dev_no;
 108    char ldp[] = "LOADPARM=[________]\n";
 109    VDev *vdev = virtio_get_device();
 110    QemuIplParameters *early_qipl = (QemuIplParameters *)QIPL_ADDRESS;
 111
 112    /*
 113     * We unconditionally enable mss support. In every sane configuration,
 114     * this will succeed; and even if it doesn't, stsch_err() can deal
 115     * with the consequences.
 116     */
 117    enable_mss_facility();
 118
 119    sclp_get_loadparm_ascii(loadparm_str);
 120    memcpy(ldp + 10, loadparm_str, LOADPARM_LEN);
 121    sclp_print(ldp);
 122
 123    memcpy(&qipl, early_qipl, sizeof(QemuIplParameters));
 124
 125    if (store_iplb(&iplb)) {
 126        switch (iplb.pbt) {
 127        case S390_IPL_TYPE_CCW:
 128            dev_no = iplb.ccw.devno;
 129            debug_print_int("device no. ", dev_no);
 130            blk_schid.ssid = iplb.ccw.ssid & 0x3;
 131            debug_print_int("ssid ", blk_schid.ssid);
 132            found = find_dev(&schib, dev_no);
 133            break;
 134        case S390_IPL_TYPE_QEMU_SCSI:
 135            vdev->scsi_device_selected = true;
 136            vdev->selected_scsi_device.channel = iplb.scsi.channel;
 137            vdev->selected_scsi_device.target = iplb.scsi.target;
 138            vdev->selected_scsi_device.lun = iplb.scsi.lun;
 139            blk_schid.ssid = iplb.scsi.ssid & 0x3;
 140            found = find_dev(&schib, iplb.scsi.devno);
 141            break;
 142        default:
 143            panic("List-directed IPL not supported yet!\n");
 144        }
 145        menu_setup();
 146    } else {
 147        for (ssid = 0; ssid < 0x3; ssid++) {
 148            blk_schid.ssid = ssid;
 149            found = find_dev(&schib, -1);
 150            if (found) {
 151                break;
 152            }
 153        }
 154    }
 155
 156    IPL_assert(found, "No virtio device found");
 157
 158    if (virtio_get_device_type() == VIRTIO_ID_NET) {
 159        sclp_print("Network boot device detected\n");
 160        vdev->netboot_start_addr = qipl.netboot_start_addr;
 161    } else {
 162        virtio_blk_setup_device(blk_schid);
 163
 164        IPL_assert(virtio_ipl_disk_is_valid(), "No valid IPL device detected");
 165    }
 166}
 167
 168int main(void)
 169{
 170    sclp_setup();
 171    virtio_setup();
 172
 173    zipl_load(); /* no return */
 174
 175    panic("Failed to load OS from hard disk\n");
 176    return 0; /* make compiler happy */
 177}
 178