/* * Copyright 2010 Tilera Corporation. All Rights Reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation, version 2. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or * NON INFRINGEMENT. See the GNU General Public License for * more details. */ #include <linux/linkage.h> #include <asm/errno.h> #include <asm/cache.h> #include <arch/chip.h> /* Access user memory, but use MMU to avoid propagating kernel exceptions. */ /* * clear_user_asm takes the user target address in r0 and the * number of bytes to zero in r1. * It returns the number of uncopiable bytes (hopefully zero) in r0. * Note that we don't use a separate .fixup section here since we fall * through into the "fixup" code as the last straight-line bundle anyway. */ STD_ENTRY(clear_user_asm) { bz r1, 2f; or r2, r0, r1 } andi r2, r2, 3 bzt r2, .Lclear_aligned_user_asm 1: { sb r0, zero; addi r0, r0, 1; addi r1, r1, -1 } bnzt r1, 1b 2: { move r0, r1; jrp lr } .pushsection __ex_table,"a" .align 4 .word 1b, 2b .popsection .Lclear_aligned_user_asm: 1: { sw r0, zero; addi r0, r0, 4; addi r1, r1, -4 } bnzt r1, 1b 2: { move r0, r1; jrp lr } STD_ENDPROC(clear_user_asm) .pushsection __ex_table,"a" .align 4 .word 1b, 2b .popsection /* * flush_user_asm takes the user target address in r0 and the * number of bytes to flush in r1. * It returns the number of unflushable bytes (hopefully zero) in r0. */ STD_ENTRY(flush_user_asm) bz r1, 2f { movei r2, L2_CACHE_BYTES; add r1, r0, r1 } { sub r2, zero, r2; addi r1, r1, L2_CACHE_BYTES-1 } { and r0, r0, r2; and r1, r1, r2 } { sub r1, r1, r0 } 1: { flush r0; addi r1, r1, -CHIP_FLUSH_STRIDE() } { addi r0, r0, CHIP_FLUSH_STRIDE(); bnzt r1, 1b } 2: { move r0, r1; jrp lr } STD_ENDPROC(flush_user_asm) .pushsection __ex_table,"a" .align 4 .word 1b, 2b .popsection /* * finv_user_asm takes the user target address in r0 and the * number of bytes to flush-invalidate in r1. * It returns the number of not finv'able bytes (hopefully zero) in r0. */ STD_ENTRY(finv_user_asm) bz r1, 2f { movei r2, L2_CACHE_BYTES; add r1, r0, r1 } { sub r2, zero, r2; addi r1, r1, L2_CACHE_BYTES-1 } { and r0, r0, r2; and r1, r1, r2 } { sub r1, r1, r0 } 1: { finv r0; addi r1, r1, -CHIP_FINV_STRIDE() } { addi r0, r0, CHIP_FINV_STRIDE(); bnzt r1, 1b } 2: { move r0, r1; jrp lr } STD_ENDPROC(finv_user_asm) .pushsection __ex_table,"a" .align 4 .word 1b, 2b .popsection