192f2ca38SAlexander Graf /* 292f2ca38SAlexander Graf * S390 virtio-ccw loading program 392f2ca38SAlexander Graf * 492f2ca38SAlexander Graf * Copyright (c) 2013 Alexander Graf <agraf@suse.de> 592f2ca38SAlexander Graf * 692f2ca38SAlexander Graf * This work is licensed under the terms of the GNU GPL, version 2 or (at 792f2ca38SAlexander Graf * your option) any later version. See the COPYING file in the top-level 892f2ca38SAlexander Graf * directory. 992f2ca38SAlexander Graf */ 1092f2ca38SAlexander Graf 1192f2ca38SAlexander Graf #include "s390-ccw.h" 1260612d5cSEugene (jno) Dvurechenski #include "virtio.h" 1392f2ca38SAlexander Graf 1492f2ca38SAlexander Graf char stack[PAGE_SIZE * 8] __attribute__((__aligned__(PAGE_SIZE))); 152be9d292SChristian Borntraeger char ring_area[PAGE_SIZE * 8] __attribute__((__aligned__(PAGE_SIZE))); 16ff151f4eSDominik Dingel uint64_t boot_value; 17f17a8430SChristian Borntraeger static struct subchannel_id blk_schid = { .one = 1 }; 18f2879a5cSChristian Borntraeger 19f2879a5cSChristian Borntraeger /* 20f2879a5cSChristian Borntraeger * Priniciples of Operations (SA22-7832-09) chapter 17 requires that 21f2879a5cSChristian Borntraeger * a subsystem-identification is at 184-187 and bytes 188-191 are zero 22f2879a5cSChristian Borntraeger * after list-directed-IPL and ccw-IPL. 23f2879a5cSChristian Borntraeger */ 24f2879a5cSChristian Borntraeger void write_subsystem_identification(void) 25f2879a5cSChristian Borntraeger { 26f2879a5cSChristian Borntraeger struct subchannel_id *schid = (struct subchannel_id *) 184; 27f2879a5cSChristian Borntraeger uint32_t *zeroes = (uint32_t *) 188; 28f2879a5cSChristian Borntraeger 29f2879a5cSChristian Borntraeger *schid = blk_schid; 30f2879a5cSChristian Borntraeger *zeroes = 0; 31f2879a5cSChristian Borntraeger } 32f2879a5cSChristian Borntraeger 3392f2ca38SAlexander Graf 3492f2ca38SAlexander Graf void virtio_panic(const char *string) 3592f2ca38SAlexander Graf { 3692f2ca38SAlexander Graf sclp_print(string); 377f61cbc1SChristian Borntraeger disabled_wait(); 3892f2ca38SAlexander Graf while (1) { } 3992f2ca38SAlexander Graf } 4092f2ca38SAlexander Graf 41*0f79b89bSAlexander Yarygin static bool find_dev(struct schib *schib, int dev_no) 4292f2ca38SAlexander Graf { 43*0f79b89bSAlexander Yarygin int i, r; 44ff151f4eSDominik Dingel 4592f2ca38SAlexander Graf for (i = 0; i < 0x10000; i++) { 4692f2ca38SAlexander Graf blk_schid.sch_no = i; 47*0f79b89bSAlexander Yarygin r = stsch_err(blk_schid, schib); 48*0f79b89bSAlexander Yarygin if ((r == 3) || (r == -EIO)) { 4922d67ab5SCornelia Huck break; 5022d67ab5SCornelia Huck } 51*0f79b89bSAlexander Yarygin if (!schib->pmcw.dnv) { 52*0f79b89bSAlexander Yarygin continue; 5392f2ca38SAlexander Graf } 54*0f79b89bSAlexander Yarygin if (!virtio_is_blk(blk_schid)) { 55*0f79b89bSAlexander Yarygin continue; 56*0f79b89bSAlexander Yarygin } 57*0f79b89bSAlexander Yarygin if ((dev_no < 0) || (schib->pmcw.dev == dev_no)) { 58*0f79b89bSAlexander Yarygin return true; 59*0f79b89bSAlexander Yarygin } 60*0f79b89bSAlexander Yarygin } 61*0f79b89bSAlexander Yarygin 62*0f79b89bSAlexander Yarygin return false; 63*0f79b89bSAlexander Yarygin } 64*0f79b89bSAlexander Yarygin 65*0f79b89bSAlexander Yarygin static void virtio_setup(uint64_t dev_info) 66*0f79b89bSAlexander Yarygin { 67*0f79b89bSAlexander Yarygin struct schib schib; 68*0f79b89bSAlexander Yarygin int ssid; 69*0f79b89bSAlexander Yarygin bool found = false; 70*0f79b89bSAlexander Yarygin uint16_t dev_no; 71*0f79b89bSAlexander Yarygin 72*0f79b89bSAlexander Yarygin /* 73*0f79b89bSAlexander Yarygin * We unconditionally enable mss support. In every sane configuration, 74*0f79b89bSAlexander Yarygin * this will succeed; and even if it doesn't, stsch_err() can deal 75*0f79b89bSAlexander Yarygin * with the consequences. 76*0f79b89bSAlexander Yarygin */ 77*0f79b89bSAlexander Yarygin enable_mss_facility(); 78*0f79b89bSAlexander Yarygin 79*0f79b89bSAlexander Yarygin if (dev_info != -1) { 80*0f79b89bSAlexander Yarygin dev_no = dev_info & 0xffff; 81*0f79b89bSAlexander Yarygin debug_print_int("device no. ", dev_no); 82*0f79b89bSAlexander Yarygin blk_schid.ssid = (dev_info >> 16) & 0x3; 83*0f79b89bSAlexander Yarygin debug_print_int("ssid ", blk_schid.ssid); 84*0f79b89bSAlexander Yarygin found = find_dev(&schib, dev_no); 85*0f79b89bSAlexander Yarygin } else { 86*0f79b89bSAlexander Yarygin for (ssid = 0; ssid < 0x3; ssid++) { 87*0f79b89bSAlexander Yarygin blk_schid.ssid = ssid; 88*0f79b89bSAlexander Yarygin found = find_dev(&schib, -1); 89*0f79b89bSAlexander Yarygin if (found) { 90*0f79b89bSAlexander Yarygin break; 9192f2ca38SAlexander Graf } 9292f2ca38SAlexander Graf } 93ff151f4eSDominik Dingel } 9492f2ca38SAlexander Graf 9592f2ca38SAlexander Graf if (!found) { 9692f2ca38SAlexander Graf virtio_panic("No virtio-blk device found!\n"); 9792f2ca38SAlexander Graf } 9892f2ca38SAlexander Graf 9992f2ca38SAlexander Graf virtio_setup_block(blk_schid); 10060612d5cSEugene (jno) Dvurechenski 10160612d5cSEugene (jno) Dvurechenski if (!virtio_ipl_disk_is_valid()) { 10260612d5cSEugene (jno) Dvurechenski virtio_panic("No valid hard disk detected.\n"); 10360612d5cSEugene (jno) Dvurechenski } 10492f2ca38SAlexander Graf } 10592f2ca38SAlexander Graf 10692f2ca38SAlexander Graf int main(void) 10792f2ca38SAlexander Graf { 10892f2ca38SAlexander Graf sclp_setup(); 109ff151f4eSDominik Dingel debug_print_int("boot reg[7] ", boot_value); 110ff151f4eSDominik Dingel virtio_setup(boot_value); 111ff151f4eSDominik Dingel 11260612d5cSEugene (jno) Dvurechenski zipl_load(); /* no return */ 11360612d5cSEugene (jno) Dvurechenski 11460612d5cSEugene (jno) Dvurechenski virtio_panic("Failed to load OS from hard disk\n"); 11560612d5cSEugene (jno) Dvurechenski return 0; /* make compiler happy */ 11692f2ca38SAlexander Graf } 117