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 15 char stack[PAGE_SIZE * 8] __attribute__((__aligned__(PAGE_SIZE))); 16 static SubChannelId blk_schid = { .one = 1 }; 17 IplParameterBlock iplb __attribute__((__aligned__(PAGE_SIZE))); 18 static char loadparm_str[LOADPARM_LEN + 1] = { 0, 0, 0, 0, 0, 0, 0, 0, 0 }; 19 QemuIplParameters 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 */ 30 void 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 39 void panic(const char *string) 40 { 41 sclp_print(string); 42 disabled_wait(); 43 while (1) { } 44 } 45 46 unsigned int get_loadparm_index(void) 47 { 48 return atoui(loadparm_str); 49 } 50 51 static 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 81 static 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 } 101 102 static 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 } 167 168 int 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