From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- arch/s390/include/asm/alternative.h | 120 ++++++++++++++++++++++++++++++++++++ 1 file changed, 120 insertions(+) create mode 100644 arch/s390/include/asm/alternative.h (limited to 'arch/s390/include/asm/alternative.h') diff --git a/arch/s390/include/asm/alternative.h b/arch/s390/include/asm/alternative.h new file mode 100644 index 0000000000..904dd049f9 --- /dev/null +++ b/arch/s390/include/asm/alternative.h @@ -0,0 +1,120 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_S390_ALTERNATIVE_H +#define _ASM_S390_ALTERNATIVE_H + +#ifndef __ASSEMBLY__ + +#include +#include +#include + +struct alt_instr { + s32 instr_offset; /* original instruction */ + s32 repl_offset; /* offset to replacement instruction */ + u16 facility; /* facility bit set for replacement */ + u8 instrlen; /* length of original instruction */ +} __packed; + +void apply_alternative_instructions(void); +void apply_alternatives(struct alt_instr *start, struct alt_instr *end); + +/* + * +---------------------------------+ + * |661: |662: + * | oldinstr | + * +---------------------------------+ + * + * .altinstr_replacement section + * +---------------------------------+ + * |6641: |6651: + * | alternative instr 1 | + * +---------------------------------+ + * |6642: |6652: + * | alternative instr 2 | + * +---------------------------------+ + * + * .altinstructions section + * +---------------------------------+ + * | alt_instr entries for each | + * | alternative instr | + * +---------------------------------+ + */ + +#define b_altinstr(num) "664"#num +#define e_altinstr(num) "665"#num +#define oldinstr_len "662b-661b" +#define altinstr_len(num) e_altinstr(num)"b-"b_altinstr(num)"b" + +#define OLDINSTR(oldinstr) \ + "661:\n\t" oldinstr "\n662:\n" + +#define ALTINSTR_ENTRY(facility, num) \ + "\t.long 661b - .\n" /* old instruction */ \ + "\t.long " b_altinstr(num)"b - .\n" /* alt instruction */ \ + "\t.word " __stringify(facility) "\n" /* facility bit */ \ + "\t.byte " oldinstr_len "\n" /* instruction len */ \ + "\t.org . - (" oldinstr_len ") + (" altinstr_len(num) ")\n" \ + "\t.org . - (" altinstr_len(num) ") + (" oldinstr_len ")\n" + +#define ALTINSTR_REPLACEMENT(altinstr, num) /* replacement */ \ + b_altinstr(num)":\n\t" altinstr "\n" e_altinstr(num) ":\n" + +/* alternative assembly primitive: */ +#define ALTERNATIVE(oldinstr, altinstr, facility) \ + ".pushsection .altinstr_replacement, \"ax\"\n" \ + ALTINSTR_REPLACEMENT(altinstr, 1) \ + ".popsection\n" \ + OLDINSTR(oldinstr) \ + ".pushsection .altinstructions,\"a\"\n" \ + ALTINSTR_ENTRY(facility, 1) \ + ".popsection\n" + +#define ALTERNATIVE_2(oldinstr, altinstr1, facility1, altinstr2, facility2)\ + ".pushsection .altinstr_replacement, \"ax\"\n" \ + ALTINSTR_REPLACEMENT(altinstr1, 1) \ + ALTINSTR_REPLACEMENT(altinstr2, 2) \ + ".popsection\n" \ + OLDINSTR(oldinstr) \ + ".pushsection .altinstructions,\"a\"\n" \ + ALTINSTR_ENTRY(facility1, 1) \ + ALTINSTR_ENTRY(facility2, 2) \ + ".popsection\n" + +/* + * Alternative instructions for different CPU types or capabilities. + * + * This allows to use optimized instructions even on generic binary + * kernels. + * + * oldinstr is padded with jump and nops at compile time if altinstr is + * longer. altinstr is padded with jump and nops at run-time during patching. + * + * For non barrier like inlines please define new variants + * without volatile and memory clobber. + */ +#define alternative(oldinstr, altinstr, facility) \ + asm_inline volatile(ALTERNATIVE(oldinstr, altinstr, facility) : : : "memory") + +#define alternative_2(oldinstr, altinstr1, facility1, altinstr2, facility2) \ + asm_inline volatile(ALTERNATIVE_2(oldinstr, altinstr1, facility1, \ + altinstr2, facility2) ::: "memory") + +/* Alternative inline assembly with input. */ +#define alternative_input(oldinstr, newinstr, feature, input...) \ + asm_inline volatile (ALTERNATIVE(oldinstr, newinstr, feature) \ + : : input) + +/* Like alternative_input, but with a single output argument */ +#define alternative_io(oldinstr, altinstr, facility, output, input...) \ + asm_inline volatile(ALTERNATIVE(oldinstr, altinstr, facility) \ + : output : input) + +/* Use this macro if more than one output parameter is needed. */ +#define ASM_OUTPUT2(a...) a + +/* Use this macro if clobbers are needed without inputs. */ +#define ASM_NO_INPUT_CLOBBER(clobber...) : clobber + +#endif /* __ASSEMBLY__ */ + +#endif /* _ASM_S390_ALTERNATIVE_H */ -- cgit v1.2.3