[S390] cio/ipl: Clean interface between cio and ipl code.

Clean interface between cio and ipl code, so Peter stops complaining.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

4 files changed, 40 insertions, 31 deletions

diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c
index f731185bf2bd..a83cf1fdd8f5 100644
--- a/arch/s390/kernel/ipl.c
+++ b/arch/s390/kernel/ipl.c
@@ -47,7 +47,7 @@ enum ipl_type {
  * Must be in data section since the bss section
  * is not cleared when these are accessed.
  */
-u16 ipl_devno __attribute__((__section__(".data"))) = 0;
+static u16 ipl_devno __attribute__((__section__(".data"))) = 0;
 u32 ipl_flags __attribute__((__section__(".data"))) = 0;
 
 static char *ipl_type_str(enum ipl_type type)
@@ -1038,6 +1038,27 @@ static int __init s390_ipl_init(void)
 
 __initcall(s390_ipl_init);
 
+void __init ipl_save_parameters(void)
+{
+        struct cio_iplinfo iplinfo;
+        unsigned int *ipl_ptr;
+        void *src, *dst;
+
+        if (cio_get_iplinfo(&iplinfo))
+                return;
+
+        ipl_devno = iplinfo.devno;
+        ipl_flags |= IPL_DEVNO_VALID;
+        if (!iplinfo.is_qdio)
+                return;
+        ipl_flags |= IPL_PARMBLOCK_VALID;
+        ipl_ptr = (unsigned int *)__LC_IPL_PARMBLOCK_PTR;
+        src = (void *)(unsigned long)*ipl_ptr;
+        dst = (void *)IPL_PARMBLOCK_ORIGIN;
+        memmove(dst, src, PAGE_SIZE);
+        *ipl_ptr = IPL_PARMBLOCK_ORIGIN;
+}
+
 static LIST_HEAD(rcall);
 static DEFINE_MUTEX(rcall_mutex);
 
diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c
index 9cb129ab5be5..21af446c1f2d 100644
--- a/drivers/s390/cio/cio.c
+++ b/drivers/s390/cio/cio.c
@@ -1048,37 +1048,19 @@ void reipl_ccw_dev(struct ccw_dev_id *devid)
         do_reipl_asm(*((__u32*)&schid));
 }
 
-static struct schib __initdata ipl_schib;
-
-/*
- * ipl_save_parameters gets called very early. It is not allowed to access
- * anything in the bss section at all. The bss section is not cleared yet,
- * but may contain some ipl parameters written by the firmware.
- * These parameters (if present) are copied to 0x2000.
- * To avoid corruption of the ipl parameters, all variables used by this
- * function must reside on the stack or in the data section.
- */
-void ipl_save_parameters(void)
+int __init cio_get_iplinfo(struct cio_iplinfo *iplinfo)
 {
         struct subchannel_id schid;
-        unsigned int *ipl_ptr;
-        void *src, *dst;
+        struct schib schib;
 
         schid = *(struct subchannel_id *)__LC_SUBCHANNEL_ID;
         if (!schid.one)
-                return;
-        if (stsch(schid, &ipl_schib))
-                return;
-        if (!ipl_schib.pmcw.dnv)
-                return;
-        ipl_devno = ipl_schib.pmcw.dev;
-        ipl_flags |= IPL_DEVNO_VALID;
-        if (!ipl_schib.pmcw.qf)
-                return;
-        ipl_flags |= IPL_PARMBLOCK_VALID;
-        ipl_ptr = (unsigned int *)__LC_IPL_PARMBLOCK_PTR;
-        src = (void *)(unsigned long)*ipl_ptr;
-        dst = (void *)IPL_PARMBLOCK_ORIGIN;
-        memmove(dst, src, PAGE_SIZE);
-        *ipl_ptr = IPL_PARMBLOCK_ORIGIN;
+                return -ENODEV;
+        if (stsch(schid, &schib))
+                return -ENODEV;
+        if (!schib.pmcw.dnv)
+                return -ENODEV;
+        iplinfo->devno = schib.pmcw.dev;
+        iplinfo->is_qdio = schib.pmcw.qf;
+        return 0;
 }
diff --git a/include/asm-s390/cio.h b/include/asm-s390/cio.h
index d92785030980..0db017bc7d09 100644
--- a/include/asm-s390/cio.h
+++ b/include/asm-s390/cio.h
@@ -292,6 +292,13 @@ extern void css_schedule_reprobe(void);
 
 extern void reipl_ccw_dev(struct ccw_dev_id *id);
 
+struct cio_iplinfo {
+        u16 devno;
+        int is_qdio;
+};
+
+extern int cio_get_iplinfo(struct cio_iplinfo *iplinfo);
+
 #endif
 
 #endif
diff --git a/include/asm-s390/ipl.h b/include/asm-s390/ipl.h
index 0eb64083480a..15bb0b529551 100644
--- a/include/asm-s390/ipl.h
+++ b/include/asm-s390/ipl.h
@@ -74,10 +74,9 @@ struct ipl_parameter_block {
 } __attribute__((packed));
 
 /*
- * IPL validity flags and parameters as detected in head.S
+ * IPL validity flags
  */
 extern u32 ipl_flags;
-extern u16 ipl_devno;
 
 extern u32 dump_prefix_page;
 extern void do_reipl(void);