Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) /* SPDX-License-Identifier: GPL-2.0 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  * arch/alpha/lib/clear_user.S
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  * Contributed by Richard Henderson <rth@tamu.edu>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  * Zero user space, handling exceptions as we go.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8)  * We have to make sure that $0 is always up-to-date and contains the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9)  * right "bytes left to zero" value (and that it is updated only _after_
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10)  * a successful copy).  There is also some rather minor exception setup
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11)  * stuff.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include <asm/export.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) /* Allow an exception for an insn; exit if we get one.  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) #define EX(x,y...)			\
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) 	99: x,##y;			\
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) 	.section __ex_table,"a";	\
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) 	.long 99b - .;			\
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) 	lda $31, $exception-99b($31); 	\
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) 	.previous
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) 	.set noat
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) 	.set noreorder
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) 	.align 4
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) 	.globl __clear_user
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) 	.ent __clear_user
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) 	.frame	$30, 0, $26
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) 	.prologue 0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) $loop:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 	and	$1, 3, $4	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 	beq	$4, 1f		# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 0:	EX( stq_u $31, 0($16) )	# e0    : zero one word
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 	subq	$0, 8, $0	# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 	subq	$4, 1, $4	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 	addq	$16, 8, $16	# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 	bne	$4, 0b		# e1    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 	unop			#       :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 1:	bic	$1, 3, $1	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 	beq	$1, $tail	# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 2:	EX( stq_u $31, 0($16) )	# e0    : zero four words
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 	subq	$0, 8, $0	# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 	EX( stq_u $31, 8($16) )	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 	subq	$0, 8, $0	# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 	EX( stq_u $31, 16($16) )	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 	subq	$0, 8, $0	# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 	EX( stq_u $31, 24($16) )	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 	subq	$0, 8, $0	# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 	subq	$1, 4, $1	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 	addq	$16, 32, $16	# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 	bne	$1, 2b		# e1    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) $tail:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 	bne	$2, 1f		# e1    : is there a tail to do?
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 	ret	$31, ($26), 1	# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 1:	EX( ldq_u $5, 0($16) )	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 	clr	$0		# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 	nop			# e1    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 	mskqh	$5, $0, $5	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 	EX( stq_u $5, 0($16) )	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 	ret	$31, ($26), 1	# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) __clear_user:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 	and	$17, $17, $0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 	and	$16, 7, $4	# e0    : find dest misalignment
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 	beq	$0, $zerolength # .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 	addq	$0, $4, $1	# e0    : bias counter
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 	and	$1, 7, $2	# e1    : number of bytes in tail
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 	srl	$1, 3, $1	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 	beq	$4, $loop	# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 	EX( ldq_u $5, 0($16) )	# e0    : load dst word to mask back in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 	beq	$1, $oneword	# .. e1 : sub-word store?
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 	mskql	$5, $16, $5	# e0    : take care of misaligned head
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 	addq	$16, 8, $16	# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 	EX( stq_u $5, -8($16) )	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 	addq	$0, $4, $0	# .. e1 : bytes left -= 8 - misalignment
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 	subq	$1, 1, $1	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 	subq	$0, 8, $0	# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 	br	$loop		# e1    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 	unop			#       :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) $oneword:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 	mskql	$5, $16, $4	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 	mskqh	$5, $2, $5	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 	or	$5, $4, $5	# e1    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 	EX( stq_u $5, 0($16) )	# e0    :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 	clr	$0		# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) $zerolength:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) $exception:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 	ret	$31, ($26), 1	# .. e1 :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 	.end __clear_user
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 	EXPORT_SYMBOL(__clear_user)