[qemu-s390x] [PATCH v5 03/15] s390-bios: decouple common boot logic from virtio

[Jason J. Herne]

Create a boot_setup function to handle getting boot information from
the machine/hypervisor. This decouples common boot logic from the
virtio code path and allows us to make use of it for the real dasd boot
scenario.

Signed-off-by: Jason J. Herne <address@hidden>
Acked-by: Halil Pasic <address@hidden>
Reviewed-by: Collin Walling <address@hidden
Reviewed-by: Thomas Huth <address@hidden>
Reviewed-by: Farhan Ali <address@hidden>
Reviewed-by: Cornelia Huck <address@hidden>
---
 pc-bios/s390-ccw/main.c | 28 ++++++++++++++++++++--------
 1 file changed, 20 insertions(+), 8 deletions(-)

diff --git a/pc-bios/s390-ccw/main.c b/pc-bios/s390-ccw/main.c
index e82fe2c..67df421 100644
--- a/pc-bios/s390-ccw/main.c
+++ b/pc-bios/s390-ccw/main.c
@@ -14,16 +14,17 @@
 
 char stack[PAGE_SIZE * 8] __attribute__((__aligned__(PAGE_SIZE)));
 static SubChannelId blk_schid = { .one = 1 };
-IplParameterBlock iplb __attribute__((__aligned__(PAGE_SIZE)));
 static char loadparm_str[LOADPARM_LEN + 1] = { 0, 0, 0, 0, 0, 0, 0, 0, 0 };
 QemuIplParameters qipl;
+IplParameterBlock iplb __attribute__((__aligned__(PAGE_SIZE)));
+static bool have_iplb;
 
 #define LOADPARM_PROMPT "PROMPT  "
 #define LOADPARM_EMPTY  "        "
 #define BOOT_MENU_FLAG_MASK (QIPL_FLAG_BM_OPTS_CMD | QIPL_FLAG_BM_OPTS_ZIPL)
 
 /*
- * Priniciples of Operations (SA22-7832-09) chapter 17 requires that
+ * Principles 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.
  */
@@ -111,23 +112,33 @@ static void css_setup(void)
     enable_mss_facility();
 }
 
+/*
+ * Collect various pieces of information from the hypervisor/hardware that
+ * we'll use to determine exactly how we'll boot.
+ */
+static void boot_setup(void)
+{
+    char lpmsg[] = "LOADPARM=[________]\n";
+
+    sclp_get_loadparm_ascii(loadparm_str);
+    memcpy(lpmsg + 10, loadparm_str, 8);
+    sclp_print(lpmsg);
+
+    have_iplb = store_iplb(&iplb);
+}
+
 static void virtio_setup(void)
 {
     Schib schib;
     int ssid;
     bool found = false;
     uint16_t dev_no;
-    char ldp[] = "LOADPARM=[________]\n";
     VDev *vdev = virtio_get_device();
     QemuIplParameters *early_qipl = (QemuIplParameters *)QIPL_ADDRESS;
 
-    sclp_get_loadparm_ascii(loadparm_str);
-    memcpy(ldp + 10, loadparm_str, LOADPARM_LEN);
-    sclp_print(ldp);
-
     memcpy(&qipl, early_qipl, sizeof(QemuIplParameters));
 
-    if (store_iplb(&iplb)) {
+    if (have_iplb) {
         switch (iplb.pbt) {
         case S390_IPL_TYPE_CCW:
             dev_no = iplb.ccw.devno;
@@ -174,6 +185,7 @@ int main(void)
 {
     sclp_setup();
     css_setup();
+    boot_setup();
     virtio_setup();
 
     zipl_load(); /* no return */
-- 
2.7.4