unicore32 additional architecture files: low-level lib: uaccess
This patch implements low-level uaccess libraries. Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn> Acked-by: Arnd Bergmann <arnd@arndb.de>
This commit is contained in:
GuanXuetao
parent
28bab059a2
commit
77c93b2f23
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@ -0,0 +1,47 @@
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/*
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* linux/arch/unicore32/include/asm/uaccess.h
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*
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* Code specific to PKUnity SoC and UniCore ISA
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*
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* Copyright (C) 2001-2010 GUAN Xue-tao
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#ifndef __UNICORE_UACCESS_H__
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#define __UNICORE_UACCESS_H__
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#include <linux/thread_info.h>
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#include <linux/errno.h>
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#include <asm/memory.h>
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#include <asm/system.h>
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#define __copy_from_user __copy_from_user
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#define __copy_to_user __copy_to_user
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#define __strncpy_from_user __strncpy_from_user
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#define __strnlen_user __strnlen_user
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#define __clear_user __clear_user
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#define __kernel_ok (segment_eq(get_fs(), KERNEL_DS))
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#define __user_ok(addr, size) (((size) <= TASK_SIZE) \
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&& ((addr) <= TASK_SIZE - (size)))
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#define __access_ok(addr, size) (__kernel_ok || __user_ok((addr), (size)))
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extern unsigned long __must_check
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__copy_from_user(void *to, const void __user *from, unsigned long n);
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extern unsigned long __must_check
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__copy_to_user(void __user *to, const void *from, unsigned long n);
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extern unsigned long __must_check
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__clear_user(void __user *addr, unsigned long n);
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extern unsigned long __must_check
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__strncpy_from_user(char *to, const char __user *from, unsigned long count);
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extern unsigned long
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__strnlen_user(const char __user *s, long n);
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#include <asm-generic/uaccess.h>
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extern int fixup_exception(struct pt_regs *regs);
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#endif /* __UNICORE_UACCESS_H__ */
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@ -0,0 +1,57 @@
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/*
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* linux/arch/unicore32/lib/clear_user.S
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*
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* Code specific to PKUnity SoC and UniCore ISA
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*
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* Copyright (C) 2001-2010 GUAN Xue-tao
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/linkage.h>
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#include <asm/assembler.h>
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.text
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/* Prototype: int __clear_user(void *addr, size_t sz)
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* Purpose : clear some user memory
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* Params : addr - user memory address to clear
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* : sz - number of bytes to clear
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* Returns : number of bytes NOT cleared
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*/
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WEAK(__clear_user)
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stm.w (lr), [sp-]
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stm.w (r1), [sp-]
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mov r2, #0
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csub.a r1, #4
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bsl 2f
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and.a ip, r0, #3
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beq 1f
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csub.a ip, #2
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strusr r2, r0, 1
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strusr r2, r0, 1, el
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strusr r2, r0, 1, sl
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rsub ip, ip, #4
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sub r1, r1, ip @ 7 6 5 4 3 2 1
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1: sub.a r1, r1, #8 @ -1 -2 -3 -4 -5 -6 -7
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strusr r2, r0, 4, ns, rept=2
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bns 1b
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add.a r1, r1, #4 @ 3 2 1 0 -1 -2 -3
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strusr r2, r0, 4, ns
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2: cand.a r1, #2 @ 1x 1x 0x 0x 1x 1x 0x
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strusr r2, r0, 1, ne, rept=2
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cand.a r1, #1 @ x1 x0 x1 x0 x1 x0 x1
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beq 3f
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USER( stb.u r2, [r0])
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3: mov r0, #0
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ldm.w (r1), [sp]+
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ldm.w (pc), [sp]+
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ENDPROC(__clear_user)
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.pushsection .fixup,"ax"
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.align 0
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9001: ldm.w (r0), [sp]+
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ldm.w (pc), [sp]+
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.popsection
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@ -0,0 +1,108 @@
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/*
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* linux/arch/unicore32/lib/copy_from_user.S
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*
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* Code specific to PKUnity SoC and UniCore ISA
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*
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* Copyright (C) 2001-2010 GUAN Xue-tao
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/linkage.h>
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#include <asm/assembler.h>
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/*
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* Prototype:
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*
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* size_t __copy_from_user(void *to, const void *from, size_t n)
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*
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* Purpose:
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*
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* copy a block to kernel memory from user memory
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*
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* Params:
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*
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* to = kernel memory
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* from = user memory
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* n = number of bytes to copy
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*
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* Return value:
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*
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* Number of bytes NOT copied.
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*/
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.macro ldr1w ptr reg abort
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ldrusr \reg, \ptr, 4, abort=\abort
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.endm
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.macro ldr4w ptr reg1 reg2 reg3 reg4 abort
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100: ldm.w (\reg1, \reg2, \reg3, \reg4), [\ptr]+
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.pushsection __ex_table, "a"
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.align 3
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.long 100b, \abort
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.popsection
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.endm
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.macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
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100: ldm.w (\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8), [\ptr]+
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.pushsection __ex_table, "a"
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.align 3
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.long 100b, \abort
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.popsection
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.endm
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.macro ldr1b ptr reg cond=al abort
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ldrusr \reg, \ptr, 1, \cond, abort=\abort
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.endm
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.macro str1w ptr reg abort
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stw.w \reg, [\ptr]+, #4
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.endm
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.macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
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stm.w (\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8), [\ptr]+
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.endm
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.macro str1b ptr reg cond=al abort
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.ifnc \cond, al
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b\cond 201f
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b 202f
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.endif
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201: stb.w \reg, [\ptr]+, #1
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202:
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.endm
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.macro enter
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mov r3, #0
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stm.w (r0, r2, r3), [sp-]
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.endm
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.macro exit
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add sp, sp, #8
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ldm.w (r0), [sp]+
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mov pc, lr
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.endm
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.text
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ENTRY(__copy_from_user)
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#include "copy_template.S"
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ENDPROC(__copy_from_user)
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.pushsection .fixup,"ax"
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.align 0
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copy_abort_preamble
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ldm.w (r1, r2), [sp]+
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sub r3, r0, r1
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rsub r2, r3, r2
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stw r2, [sp]
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mov r1, #0
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b.l memset
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ldw.w r0, [sp]+, #4
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copy_abort_end
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.popsection
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@ -0,0 +1,39 @@
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/*
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* linux/arch/unicore32/lib/copy_page.S
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*
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* Code specific to PKUnity SoC and UniCore ISA
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*
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* Copyright (C) 2001-2010 GUAN Xue-tao
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* ASM optimised string functions
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*/
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#include <linux/linkage.h>
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#include <asm/assembler.h>
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#include <generated/asm-offsets.h>
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#include <asm/cache.h>
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#define COPY_COUNT (PAGE_SZ/256)
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.text
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.align 5
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/*
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* UniCore optimised copy_page routine
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*/
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ENTRY(copy_page)
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stm.w (r17 - r19, lr), [sp-]
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mov r17, r0
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mov r18, r1
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mov r19, #COPY_COUNT
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1:
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.rept 4
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ldm.w (r0 - r15), [r18]+
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stm.w (r0 - r15), [r17]+
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.endr
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sub.a r19, r19, #1
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bne 1b
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ldm.w (r17 - r19, pc), [sp]+
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ENDPROC(copy_page)
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/*
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* linux/arch/unicore32/lib/copy_template.S
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*
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* Code specific to PKUnity SoC and UniCore ISA
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*
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* Copyright (C) 2001-2010 GUAN Xue-tao
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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/*
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* Theory of operation
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* -------------------
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*
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* This file provides the core code for a forward memory copy used in
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* the implementation of memcopy(), copy_to_user() and copy_from_user().
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*
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* The including file must define the following accessor macros
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* according to the need of the given function:
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*
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* ldr1w ptr reg abort
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*
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* This loads one word from 'ptr', stores it in 'reg' and increments
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* 'ptr' to the next word. The 'abort' argument is used for fixup tables.
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*
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* ldr4w ptr reg1 reg2 reg3 reg4 abort
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* ldr8w ptr, reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
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*
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* This loads four or eight words starting from 'ptr', stores them
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* in provided registers and increments 'ptr' past those words.
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* The'abort' argument is used for fixup tables.
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*
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* ldr1b ptr reg cond abort
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*
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* Similar to ldr1w, but it loads a byte and increments 'ptr' one byte.
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* It also must apply the condition code if provided, otherwise the
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* "al" condition is assumed by default.
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*
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* str1w ptr reg abort
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* str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
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* str1b ptr reg cond abort
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*
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* Same as their ldr* counterparts, but data is stored to 'ptr' location
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* rather than being loaded.
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*
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* enter
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*
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* Preserve the provided registers on the stack plus any additional
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* data as needed by the implementation including this code. Called
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* upon code entry.
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*
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* exit
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*
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* Restore registers with the values previously saved with the
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* 'preserv' macro. Called upon code termination.
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*/
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enter
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sub.a r2, r2, #4
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bsl 8f
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and.a ip, r0, #3
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bne 9f
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and.a ip, r1, #3
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bne 10f
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1: sub.a r2, r2, #(28)
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stm.w (r5 - r8), [sp-]
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bsl 5f
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3:
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4: ldr8w r1, r3, r4, r5, r6, r7, r8, r10, r11, abort=20f
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sub.a r2, r2, #32
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str8w r0, r3, r4, r5, r6, r7, r8, r10, r11, abort=20f
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beg 3b
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5: and.a ip, r2, #28
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rsub ip, ip, #32
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beq 7f
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add pc, pc, ip @ C is always clear here
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nop
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ldr1w r1, r3, abort=20f
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ldr1w r1, r4, abort=20f
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ldr1w r1, r5, abort=20f
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ldr1w r1, r6, abort=20f
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ldr1w r1, r7, abort=20f
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ldr1w r1, r8, abort=20f
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ldr1w r1, r11, abort=20f
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add pc, pc, ip
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nop
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str1w r0, r3, abort=20f
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str1w r0, r4, abort=20f
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str1w r0, r5, abort=20f
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str1w r0, r6, abort=20f
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str1w r0, r7, abort=20f
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str1w r0, r8, abort=20f
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str1w r0, r11, abort=20f
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7: ldm.w (r5 - r8), [sp]+
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8: mov.a r2, r2 << #31
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ldr1b r1, r3, ne, abort=21f
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ldr1b r1, r4, ea, abort=21f
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ldr1b r1, r10, ea, abort=21f
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str1b r0, r3, ne, abort=21f
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str1b r0, r4, ea, abort=21f
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str1b r0, r10, ea, abort=21f
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exit
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9: rsub ip, ip, #4
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csub.a ip, #2
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ldr1b r1, r3, sg, abort=21f
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ldr1b r1, r4, eg, abort=21f
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ldr1b r1, r11, abort=21f
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str1b r0, r3, sg, abort=21f
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str1b r0, r4, eg, abort=21f
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sub.a r2, r2, ip
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str1b r0, r11, abort=21f
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bsl 8b
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and.a ip, r1, #3
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beq 1b
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10: andn r1, r1, #3
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csub.a ip, #2
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ldr1w r1, r11, abort=21f
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beq 17f
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bsg 18f
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.macro forward_copy_shift a b
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sub.a r2, r2, #28
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bsl 14f
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11: stm.w (r5 - r9), [sp-]
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12:
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ldr4w r1, r4, r5, r6, r7, abort=19f
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mov r3, r11 pull #\a
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sub.a r2, r2, #32
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ldr4w r1, r8, r9, r10, r11, abort=19f
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or r3, r3, r4 push #\b
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mov r4, r4 pull #\a
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or r4, r4, r5 push #\b
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mov r5, r5 pull #\a
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or r5, r5, r6 push #\b
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mov r6, r6 pull #\a
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or r6, r6, r7 push #\b
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mov r7, r7 pull #\a
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or r7, r7, r8 push #\b
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mov r8, r8 pull #\a
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or r8, r8, r9 push #\b
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mov r9, r9 pull #\a
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or r9, r9, r10 push #\b
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mov r10, r10 pull #\a
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or r10, r10, r11 push #\b
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str8w r0, r3, r4, r5, r6, r7, r8, r9, r10, , abort=19f
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beg 12b
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ldm.w (r5 - r9), [sp]+
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14: and.a ip, r2, #28
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beq 16f
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15: mov r3, r11 pull #\a
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ldr1w r1, r11, abort=21f
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sub.a ip, ip, #4
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or r3, r3, r11 push #\b
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str1w r0, r3, abort=21f
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bsg 15b
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16: sub r1, r1, #(\b / 8)
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b 8b
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.endm
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forward_copy_shift a=8 b=24
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17: forward_copy_shift a=16 b=16
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18: forward_copy_shift a=24 b=8
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/*
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* Abort preamble and completion macros.
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* If a fixup handler is required then those macros must surround it.
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* It is assumed that the fixup code will handle the private part of
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* the exit macro.
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*/
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.macro copy_abort_preamble
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19: ldm.w (r5 - r9), [sp]+
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b 21f
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299: .word 0 @ store lr
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@ to avoid function call in fixup
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20: ldm.w (r5 - r8), [sp]+
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21:
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adr r1, 299b
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stw lr, [r1]
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.endm
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.macro copy_abort_end
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adr lr, 299b
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ldw pc, [lr]
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.endm
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@ -0,0 +1,96 @@
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/*
|
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* linux/arch/unicore32/lib/copy_to_user.S
|
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*
|
||||
* Code specific to PKUnity SoC and UniCore ISA
|
||||
*
|
||||
* Copyright (C) 2001-2010 GUAN Xue-tao
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License version 2 as
|
||||
* published by the Free Software Foundation.
|
||||
*/
|
||||
|
||||
#include <linux/linkage.h>
|
||||
#include <asm/assembler.h>
|
||||
|
||||
/*
|
||||
* Prototype:
|
||||
*
|
||||
* size_t __copy_to_user(void *to, const void *from, size_t n)
|
||||
*
|
||||
* Purpose:
|
||||
*
|
||||
* copy a block to user memory from kernel memory
|
||||
*
|
||||
* Params:
|
||||
*
|
||||
* to = user memory
|
||||
* from = kernel memory
|
||||
* n = number of bytes to copy
|
||||
*
|
||||
* Return value:
|
||||
*
|
||||
* Number of bytes NOT copied.
|
||||
*/
|
||||
|
||||
.macro ldr1w ptr reg abort
|
||||
ldw.w \reg, [\ptr]+, #4
|
||||
.endm
|
||||
|
||||
.macro ldr4w ptr reg1 reg2 reg3 reg4 abort
|
||||
ldm.w (\reg1, \reg2, \reg3, \reg4), [\ptr]+
|
||||
.endm
|
||||
|
||||
.macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
|
||||
ldm.w (\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8), [\ptr]+
|
||||
.endm
|
||||
|
||||
.macro ldr1b ptr reg cond=al abort
|
||||
notcond \cond, .+8
|
||||
ldb.w \reg, [\ptr]+, #1
|
||||
.endm
|
||||
|
||||
.macro str1w ptr reg abort
|
||||
strusr \reg, \ptr, 4, abort=\abort
|
||||
.endm
|
||||
|
||||
.macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
|
||||
100: stm.w (\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8), [\ptr]+
|
||||
|
||||
.pushsection __ex_table, "a"
|
||||
.long 100b, \abort
|
||||
.popsection
|
||||
.endm
|
||||
|
||||
.macro str1b ptr reg cond=al abort
|
||||
strusr \reg, \ptr, 1, \cond, abort=\abort
|
||||
.endm
|
||||
|
||||
.macro enter
|
||||
mov r3, #0
|
||||
stm.w (r0, r2, r3), [sp-]
|
||||
.endm
|
||||
|
||||
.macro exit
|
||||
add sp, sp, #8
|
||||
ldm.w (r0), [sp]+
|
||||
mov pc, lr
|
||||
.endm
|
||||
|
||||
.text
|
||||
|
||||
WEAK(__copy_to_user)
|
||||
|
||||
#include "copy_template.S"
|
||||
|
||||
ENDPROC(__copy_to_user)
|
||||
|
||||
.pushsection .fixup,"ax"
|
||||
.align 0
|
||||
copy_abort_preamble
|
||||
ldm.w (r1, r2, r3), [sp]+
|
||||
sub r0, r0, r1
|
||||
rsub r0, r0, r2
|
||||
copy_abort_end
|
||||
.popsection
|
||||
|
||||
|
|
@ -0,0 +1,45 @@
|
|||
/*
|
||||
* linux/arch/unicore32/lib/strncpy_from_user.S
|
||||
*
|
||||
* Code specific to PKUnity SoC and UniCore ISA
|
||||
*
|
||||
* Copyright (C) 2001-2010 GUAN Xue-tao
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License version 2 as
|
||||
* published by the Free Software Foundation.
|
||||
*/
|
||||
#include <linux/linkage.h>
|
||||
#include <asm/assembler.h>
|
||||
#include <asm/errno.h>
|
||||
|
||||
.text
|
||||
.align 5
|
||||
|
||||
/*
|
||||
* Copy a string from user space to kernel space.
|
||||
* r0 = dst, r1 = src, r2 = byte length
|
||||
* returns the number of characters copied (strlen of copied string),
|
||||
* -EFAULT on exception, or "len" if we fill the whole buffer
|
||||
*/
|
||||
ENTRY(__strncpy_from_user)
|
||||
mov ip, r1
|
||||
1: sub.a r2, r2, #1
|
||||
ldrusr r3, r1, 1, ns
|
||||
bfs 2f
|
||||
stb.w r3, [r0]+, #1
|
||||
cxor.a r3, #0
|
||||
bne 1b
|
||||
sub r1, r1, #1 @ take NUL character out of count
|
||||
2: sub r0, r1, ip
|
||||
mov pc, lr
|
||||
ENDPROC(__strncpy_from_user)
|
||||
|
||||
.pushsection .fixup,"ax"
|
||||
.align 0
|
||||
9001: mov r3, #0
|
||||
stb r3, [r0+], #0 @ null terminate
|
||||
mov r0, #-EFAULT
|
||||
mov pc, lr
|
||||
.popsection
|
||||
|
||||
|
|
@ -0,0 +1,42 @@
|
|||
/*
|
||||
* linux/arch/unicore32/lib/strnlen_user.S
|
||||
*
|
||||
* Code specific to PKUnity SoC and UniCore ISA
|
||||
*
|
||||
* Copyright (C) 2001-2010 GUAN Xue-tao
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License version 2 as
|
||||
* published by the Free Software Foundation.
|
||||
*/
|
||||
#include <linux/linkage.h>
|
||||
#include <asm/assembler.h>
|
||||
#include <asm/errno.h>
|
||||
|
||||
.text
|
||||
.align 5
|
||||
|
||||
/* Prototype: unsigned long __strnlen_user(const char *str, long n)
|
||||
* Purpose : get length of a string in user memory
|
||||
* Params : str - address of string in user memory
|
||||
* Returns : length of string *including terminator*
|
||||
* or zero on exception, or n + 1 if too long
|
||||
*/
|
||||
ENTRY(__strnlen_user)
|
||||
mov r2, r0
|
||||
1:
|
||||
ldrusr r3, r0, 1
|
||||
cxor.a r3, #0
|
||||
beq 2f
|
||||
sub.a r1, r1, #1
|
||||
bne 1b
|
||||
add r0, r0, #1
|
||||
2: sub r0, r0, r2
|
||||
mov pc, lr
|
||||
ENDPROC(__strnlen_user)
|
||||
|
||||
.pushsection .fixup,"ax"
|
||||
.align 0
|
||||
9001: mov r0, #0
|
||||
mov pc, lr
|
||||
.popsection
|
||||
Loading…
Reference in New Issue