s390/boot: move sclp early buffer from fixed address in asm to C

To make the decompressor relocatable, the early SCLP buffer with a fixed
address must be replaced with a relocatable C buffer of the according size
and alignment as required by SCLP.

Introduce a new function sclp_early_set_buffer() into the SCLP driver
which enables the decompressor to change the SCLP early buffer at any time.
This will be useful when the decompressor becomes fully relocatable and
might need to change the SCLP early buffer to one with an address < 2G
as required by SCLP because it was loaded at an address >= 2G.

Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/arch/s390/boot/boot.h b/arch/s390/boot/boot.h
index 3d7d5ef4d169..716c35c1d78f 100644
--- a/arch/s390/boot/boot.h
+++ b/arch/s390/boot/boot.h
@@ -13,6 +13,7 @@ void setup_boot_command_line(void);
 void parse_boot_command_line(void);
 void verify_facilities(void);
 void print_missing_facilities(void);
+void sclp_early_setup_buffer(void);
 void print_pgm_check_info(void);
 unsigned long get_random_base(unsigned long safe_addr);
 void __printf(1, 2) decompressor_printk(const char *fmt, ...);