1 /* 2 * linux/lib/raid6/neon.c - RAID6 syndrome calculation using ARM NEON intrinsics 3 * 4 * Copyright (C) 2013 Linaro Ltd <ard.biesheuvel@linaro.org> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 */ 10 11 #include <linux/raid/pq.h> 12 13 #ifdef __KERNEL__ 14 #include <asm/neon.h> 15 #else 16 #define kernel_neon_begin() 17 #define kernel_neon_end() 18 #define cpu_has_neon() (1) 19 #endif 20 21 /* 22 * There are 2 reasons these wrappers are kept in a separate compilation unit 23 * from the actual implementations in neonN.c (generated from neon.uc by 24 * unroll.awk): 25 * - the actual implementations use NEON intrinsics, and the GCC support header 26 * (arm_neon.h) is not fully compatible (type wise) with the kernel; 27 * - the neonN.c files are compiled with -mfpu=neon and optimization enabled, 28 * and we have to make sure that we never use *any* NEON/VFP instructions 29 * outside a kernel_neon_begin()/kernel_neon_end() pair. 30 */ 31 32 #define RAID6_NEON_WRAPPER(_n) \ 33 static void raid6_neon ## _n ## _gen_syndrome(int disks, \ 34 size_t bytes, void **ptrs) \ 35 { \ 36 void raid6_neon ## _n ## _gen_syndrome_real(int, \ 37 unsigned long, void**); \ 38 kernel_neon_begin(); \ 39 raid6_neon ## _n ## _gen_syndrome_real(disks, \ 40 (unsigned long)bytes, ptrs); \ 41 kernel_neon_end(); \ 42 } \ 43 struct raid6_calls const raid6_neonx ## _n = { \ 44 raid6_neon ## _n ## _gen_syndrome, \ 45 NULL, /* XOR not yet implemented */ \ 46 raid6_have_neon, \ 47 "neonx" #_n, \ 48 0 \ 49 } 50 51 static int raid6_have_neon(void) 52 { 53 return cpu_has_neon(); 54 } 55 56 RAID6_NEON_WRAPPER(1); 57 RAID6_NEON_WRAPPER(2); 58 RAID6_NEON_WRAPPER(4); 59 RAID6_NEON_WRAPPER(8); 60