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-rw-r--r--qemu/pc-bios/s390-ccw/main.c100
1 files changed, 100 insertions, 0 deletions
diff --git a/qemu/pc-bios/s390-ccw/main.c b/qemu/pc-bios/s390-ccw/main.c
new file mode 100644
index 000000000..584d4a276
--- /dev/null
+++ b/qemu/pc-bios/s390-ccw/main.c
@@ -0,0 +1,100 @@
+/*
+ * S390 virtio-ccw loading program
+ *
+ * Copyright (c) 2013 Alexander Graf <agraf@suse.de>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or (at
+ * your option) any later version. See the COPYING file in the top-level
+ * directory.
+ */
+
+#include "s390-ccw.h"
+#include "virtio.h"
+
+char stack[PAGE_SIZE * 8] __attribute__((__aligned__(PAGE_SIZE)));
+char ring_area[PAGE_SIZE * 8] __attribute__((__aligned__(PAGE_SIZE)));
+uint64_t boot_value;
+static struct subchannel_id blk_schid = { .one = 1 };
+
+/*
+ * Priniciples of Operations (SA22-7832-09) chapter 17 requires that
+ * a subsystem-identification is at 184-187 and bytes 188-191 are zero
+ * after list-directed-IPL and ccw-IPL.
+ */
+void write_subsystem_identification(void)
+{
+ struct subchannel_id *schid = (struct subchannel_id *) 184;
+ uint32_t *zeroes = (uint32_t *) 188;
+
+ *schid = blk_schid;
+ *zeroes = 0;
+}
+
+
+void virtio_panic(const char *string)
+{
+ sclp_print(string);
+ disabled_wait();
+ while (1) { }
+}
+
+static void virtio_setup(uint64_t dev_info)
+{
+ struct schib schib;
+ int i;
+ int r;
+ bool found = false;
+ bool check_devno = false;
+ uint16_t dev_no = -1;
+
+ if (dev_info != -1) {
+ check_devno = true;
+ dev_no = dev_info & 0xffff;
+ debug_print_int("device no. ", dev_no);
+ blk_schid.ssid = (dev_info >> 16) & 0x3;
+ if (blk_schid.ssid != 0) {
+ debug_print_int("ssid ", blk_schid.ssid);
+ if (enable_mss_facility() != 0) {
+ virtio_panic("Failed to enable mss facility\n");
+ }
+ }
+ }
+
+ for (i = 0; i < 0x10000; i++) {
+ blk_schid.sch_no = i;
+ r = stsch_err(blk_schid, &schib);
+ if (r == 3) {
+ break;
+ }
+ if (schib.pmcw.dnv) {
+ if (!check_devno || (schib.pmcw.dev == dev_no)) {
+ if (virtio_is_blk(blk_schid)) {
+ found = true;
+ break;
+ }
+ }
+ }
+ }
+
+ if (!found) {
+ virtio_panic("No virtio-blk device found!\n");
+ }
+
+ virtio_setup_block(blk_schid);
+
+ if (!virtio_ipl_disk_is_valid()) {
+ virtio_panic("No valid hard disk detected.\n");
+ }
+}
+
+int main(void)
+{
+ sclp_setup();
+ debug_print_int("boot reg[7] ", boot_value);
+ virtio_setup(boot_value);
+
+ zipl_load(); /* no return */
+
+ virtio_panic("Failed to load OS from hard disk\n");
+ return 0; /* make compiler happy */
+}