|  | /* | 
|  | * Copyright 2011 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) | 
|  | { beqz r1, 2f; or r2, r0, r1 } | 
|  | andi r2, r2, 7 | 
|  | beqzt r2, .Lclear_aligned_user_asm | 
|  | 1:      { st1 r0, zero; addi r0, r0, 1; addi r1, r1, -1 } | 
|  | bnezt r1, 1b | 
|  | 2:      { move r0, r1; jrp lr } | 
|  | .pushsection __ex_table,"a" | 
|  | .align 8 | 
|  | .quad 1b, 2b | 
|  | .popsection | 
|  |  | 
|  | .Lclear_aligned_user_asm: | 
|  | 1:      { st r0, zero; addi r0, r0, 8; addi r1, r1, -8 } | 
|  | bnezt r1, 1b | 
|  | 2:      { move r0, r1; jrp lr } | 
|  | STD_ENDPROC(clear_user_asm) | 
|  | .pushsection __ex_table,"a" | 
|  | .align 8 | 
|  | .quad 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) | 
|  | beqz 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(); bnezt r1, 1b } | 
|  | 2:      { move r0, r1; jrp lr } | 
|  | STD_ENDPROC(flush_user_asm) | 
|  | .pushsection __ex_table,"a" | 
|  | .align 8 | 
|  | .quad 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) | 
|  | beqz 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(); bnezt r1, 1b } | 
|  | 2:      { move r0, r1; jrp lr } | 
|  | STD_ENDPROC(finv_user_asm) | 
|  | .pushsection __ex_table,"a" | 
|  | .align 8 | 
|  | .quad 1b, 2b | 
|  | .popsection |