pc-bios/s390-ccw: Get device address via diag 308/6

To IPL from a device, pc-bios receives from qemu a device address via
general register 7. The better way to do it is to use diag308/6
instruction which returns so called
"IplParameterBlock". IplParameterBlock contains the device address for
IPL and additional parameters that can be used by pc-bios.

This patch allows pc-bios to get device address via diag308/6 and
doesn't use gr7 passed boot information anymore.

Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

1 files changed, 79 insertions, 0 deletions

diff --git a/pc-bios/s390-ccw/iplb.h b/pc-bios/s390-ccw/iplb.h
new file mode 100644
index 0000000000..1cf509f497
--- /dev/null
+++ b/pc-bios/s390-ccw/iplb.h
@@ -0,0 +1,79 @@
+/*
+ * QEMU S390 IPL Block
+ *
+ * Copyright 2015 IBM Corp.
+ * Author(s): Alexander Yarygin <yarygin@linux.vnet.ibm.com>
+ *
+ * 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.
+ */
+
+#ifndef IPLB_H
+#define IPLB_H
+
+struct IplBlockCcw {
+    uint8_t  reserved0[85];
+    uint8_t  ssid;
+    uint16_t devno;
+    uint8_t  vm_flags;
+    uint8_t  reserved3[3];
+    uint32_t vm_parm_len;
+    uint8_t  nss_name[8];
+    uint8_t  vm_parm[64];
+    uint8_t  reserved4[8];
+} __attribute__ ((packed));
+typedef struct IplBlockCcw IplBlockCcw;
+
+struct IplBlockFcp {
+    uint8_t  reserved1[305 - 1];
+    uint8_t  opt;
+    uint8_t  reserved2[3];
+    uint16_t reserved3;
+    uint16_t devno;
+    uint8_t  reserved4[4];
+    uint64_t wwpn;
+    uint64_t lun;
+    uint32_t bootprog;
+    uint8_t  reserved5[12];
+    uint64_t br_lba;
+    uint32_t scp_data_len;
+    uint8_t  reserved6[260];
+    uint8_t  scp_data[];
+} __attribute__ ((packed));
+typedef struct IplBlockFcp IplBlockFcp;
+
+struct IplParameterBlock {
+    uint32_t len;
+    uint8_t  reserved0[3];
+    uint8_t  version;
+    uint32_t blk0_len;
+    uint8_t  pbt;
+    uint8_t  flags;
+    uint16_t reserved01;
+    uint8_t  loadparm[8];
+    union {
+        IplBlockCcw ccw;
+        IplBlockFcp fcp;
+    };
+} __attribute__ ((packed));
+typedef struct IplParameterBlock IplParameterBlock;
+
+extern IplParameterBlock iplb __attribute__((__aligned__(PAGE_SIZE)));
+
+#define S390_IPL_TYPE_FCP 0x00
+#define S390_IPL_TYPE_CCW 0x02
+
+static inline bool store_iplb(IplParameterBlock *iplb)
+{
+    register unsigned long addr asm("0") = (unsigned long) iplb;
+    register unsigned long rc asm("1") = 0;
+
+    asm volatile ("diag %0,%2,0x308\n"
+                  : "+d" (addr), "+d" (rc)
+                  : "d" (6)
+                  : "memory", "cc");
+    return rc == 0x01;
+}
+
+#endif /* IPLB_H */