[S390] dasd: Add ipldev parameter.

Specifying 'ipldev' in the dasd= kernel parameter will automatically
activate the boot device for use by the dasd driver.

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

1 files changed, 17 insertions, 0 deletions

diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c
index 66958b8d7c4..6a89cefe99b 100644
--- a/drivers/s390/block/dasd_devmap.c
+++ b/drivers/s390/block/dasd_devmap.c
@@ -19,6 +19,7 @@
 
 #include <asm/debug.h>
 #include <asm/uaccess.h>
+#include <asm/ipl.h>
 
 /* This is ugly... */
 #define PRINTK_HEADER "dasd_devmap:"
@@ -133,6 +134,8 @@ dasd_call_setup(char *str)
 __setup ("dasd=", dasd_call_setup);
 #endif  /* #ifndef MODULE */
 
+#define DASD_IPLDEV     "ipldev"
+
 /*
  * Read a device busid/devno from a string.
  */
@@ -141,6 +144,20 @@ dasd_busid(char **str, int *id0, int *id1, int *devno)
 {
         int val, old_style;
 
+        /* Interpret ipldev busid */
+        if (strncmp(DASD_IPLDEV, *str, strlen(DASD_IPLDEV)) == 0) {
+                if (ipl_info.type != IPL_TYPE_CCW) {
+                        MESSAGE(KERN_ERR, "%s", "ipl device is not a ccw "
+                                "device");
+                        return -EINVAL;
+                }
+                *id0 = 0;
+                *id1 = ipl_info.data.ccw.dev_id.ssid;
+                *devno = ipl_info.data.ccw.dev_id.devno;
+                *str += strlen(DASD_IPLDEV);
+
+                return 0;
+        }
         /* check for leading '0x' */
         old_style = 0;
         if ((*str)[0] == '0' && (*str)[1] == 'x') {