diff options
Diffstat (limited to 'arch/s390/include/asm/alternative-asm.h')
| -rw-r--r-- | arch/s390/include/asm/alternative-asm.h | 76 |
1 files changed, 9 insertions, 67 deletions
diff --git a/arch/s390/include/asm/alternative-asm.h b/arch/s390/include/asm/alternative-asm.h index bb3837d7387c..7db046596b93 100644 --- a/arch/s390/include/asm/alternative-asm.h +++ b/arch/s390/include/asm/alternative-asm.h @@ -5,19 +5,6 @@ #ifdef __ASSEMBLY__ /* - * Check the length of an instruction sequence. The length may not be larger - * than 254 bytes and it has to be divisible by 2. - */ -.macro alt_len_check start,end - .if ( \end - \start ) > 254 - .error "cpu alternatives does not support instructions blocks > 254 bytes\n" - .endif - .if ( \end - \start ) % 2 - .error "cpu alternatives instructions length is odd\n" - .endif -.endm - -/* * Issue one struct alt_instr descriptor entry (need to put it into * the section .altinstructions, see below). This entry contains * enough information for the alternatives patching code to patch an @@ -28,66 +15,29 @@ .long \alt_start - . .word \feature .byte \orig_end - \orig_start - .byte \alt_end - \alt_start -.endm - -/* - * Fill up @bytes with nops. The macro emits 6-byte nop instructions - * for the bulk of the area, possibly followed by a 4-byte and/or - * a 2-byte nop if the size of the area is not divisible by 6. - */ -.macro alt_pad_fill bytes - .rept ( \bytes ) / 6 - brcl 0,0 - .endr - .rept ( \bytes ) % 6 / 4 - nop - .endr - .rept ( \bytes ) % 6 % 4 / 2 - nopr - .endr -.endm - -/* - * Fill up @bytes with nops. If the number of bytes is larger - * than 6, emit a jg instruction to branch over all nops, then - * fill an area of size (@bytes - 6) with nop instructions. - */ -.macro alt_pad bytes - .if ( \bytes > 0 ) - .if ( \bytes > 6 ) - jg . + \bytes - alt_pad_fill \bytes - 6 - .else - alt_pad_fill \bytes - .endif - .endif + .org . - ( \orig_end - \orig_start ) + ( \alt_end - \alt_start ) + .org . - ( \alt_end - \alt_start ) + ( \orig_end - \orig_start ) .endm /* * Define an alternative between two instructions. If @feature is * present, early code in apply_alternatives() replaces @oldinstr with - * @newinstr. ".skip" directive takes care of proper instruction padding - * in case @newinstr is longer than @oldinstr. + * @newinstr. */ .macro ALTERNATIVE oldinstr, newinstr, feature .pushsection .altinstr_replacement,"ax" 770: \newinstr 771: .popsection 772: \oldinstr -773: alt_len_check 770b, 771b - alt_len_check 772b, 773b - alt_pad ( ( 771b - 770b ) - ( 773b - 772b ) ) -774: .pushsection .altinstructions,"a" - alt_entry 772b, 774b, 770b, 771b, \feature +773: .pushsection .altinstructions,"a" + alt_entry 772b, 773b, 770b, 771b, \feature .popsection .endm /* * Define an alternative between two instructions. If @feature is * present, early code in apply_alternatives() replaces @oldinstr with - * @newinstr. ".skip" directive takes care of proper instruction padding - * in case @newinstr is longer than @oldinstr. + * @newinstr. */ .macro ALTERNATIVE_2 oldinstr, newinstr1, feature1, newinstr2, feature2 .pushsection .altinstr_replacement,"ax" @@ -95,17 +45,9 @@ 771: \newinstr2 772: .popsection 773: \oldinstr -774: alt_len_check 770b, 771b - alt_len_check 771b, 772b - alt_len_check 773b, 774b - .if ( 771b - 770b > 772b - 771b ) - alt_pad ( ( 771b - 770b ) - ( 774b - 773b ) ) - .else - alt_pad ( ( 772b - 771b ) - ( 774b - 773b ) ) - .endif -775: .pushsection .altinstructions,"a" - alt_entry 773b, 775b, 770b, 771b,\feature1 - alt_entry 773b, 775b, 771b, 772b,\feature2 +774: .pushsection .altinstructions,"a" + alt_entry 773b, 774b, 770b, 771b,\feature1 + alt_entry 773b, 774b, 771b, 772b,\feature2 .popsection .endm |