diff options
Diffstat (limited to 'drivers/s390/cio/cio.c')
| -rw-r--r-- | drivers/s390/cio/cio.c | 38 |
1 files changed, 36 insertions, 2 deletions
diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c index 050963f15802..61eb7caa1567 100644 --- a/drivers/s390/cio/cio.c +++ b/drivers/s390/cio/cio.c @@ -16,11 +16,10 @@ #include <linux/device.h> #include <linux/kernel_stat.h> #include <linux/interrupt.h> - #include <asm/cio.h> #include <asm/delay.h> #include <asm/irq.h> - +#include <asm/setup.h> #include "airq.h" #include "cio.h" #include "css.h" @@ -909,3 +908,38 @@ void reipl_ccw_dev(struct ccw_dev_id *devid) cio_reset_channel_paths(); do_reipl_asm(*((__u32*)&schid)); } + +extern struct schib 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) +{ + struct subchannel_id schid; + unsigned int *ipl_ptr; + void *src, *dst; + + 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; +} |