s390/sclp: make early sclp code readable

This patch

 - unifies the old sclp early code and the sclp early printk code, so
   they can use common functions

 - makes sure all sclp early functions and variables have the same
   "sclp_early" prefix

 - converts the sclp early printk code into readable code by using
   existing data structures instead of hard coded magic arrays

 - splits the early sclp code into two files: sclp_early.c and
   sclp_early_core.c. The core file contains everything that is
   required by the kernel decompressor and may not call functions not
   contained within the core file. Otherwise the result would be a
   link error.

 - changes interrupt handling to be completely synchronous. The old
   early sclp code had a small window which allowed to receive several
   interrupts instead of exactly the single expected interrupt. This
   did hide a subtle potential bug, which is fixed with this large
   rework.

 - contains a couple of small cleanups.

Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 7 insertions, 6 deletions

diff --git a/arch/s390/include/asm/sclp.h b/arch/s390/include/asm/sclp.h
index 415eaace3f1b..ace3bd315438 100644
--- a/arch/s390/include/asm/sclp.h
+++ b/arch/s390/include/asm/sclp.h
@@ -101,7 +101,12 @@ struct zpci_report_error_header {
 	u8 data[0];	/* Subsequent Data passed verbatim to SCLP ET 24 */
 } __packed;
 
-int _sclp_get_core_info_early(struct sclp_core_info *info);
+int sclp_early_get_core_info(struct sclp_core_info *info);
+void sclp_early_get_ipl_info(struct sclp_ipl_info *info);
+void sclp_early_detect(void);
+void sclp_early_printk(const char *s);
+void __sclp_early_printk(const char *s, unsigned int len);
+
 int _sclp_get_core_info(struct sclp_core_info *info);
 int sclp_core_configure(u8 core);
 int sclp_core_deconfigure(u8 core);
@@ -110,21 +115,17 @@ int sclp_sdias_copy(void *dest, int blk_num, int nr_blks);
 int sclp_chp_configure(struct chp_id chpid);
 int sclp_chp_deconfigure(struct chp_id chpid);
 int sclp_chp_read_info(struct sclp_chp_info *info);
-void sclp_get_ipl_info(struct sclp_ipl_info *info);
 int sclp_pci_configure(u32 fid);
 int sclp_pci_deconfigure(u32 fid);
 int sclp_pci_report(struct zpci_report_error_header *report, u32 fh, u32 fid);
 int memcpy_hsa_kernel(void *dest, unsigned long src, size_t count);
 int memcpy_hsa_user(void __user *dest, unsigned long src, size_t count);
-void sclp_early_detect(void);
-void _sclp_print_early(const char *);
-void __sclp_print_early(const char *s, unsigned int len);
 void sclp_ocf_cpc_name_copy(char *dst);
 
 static inline int sclp_get_core_info(struct sclp_core_info *info, int early)
 {
 	if (early)
-		return _sclp_get_core_info_early(info);
+		return sclp_early_get_core_info(info);
 	return _sclp_get_core_info(info);
 }