1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 #include <unistd.h> 29 #include <sys/cachectl.h> 30 31 #ifdef DEBUG 32 #include <private/libc_logging.h> 33 #define XLOG(...) __libc_format_log(ANDROID_LOG_DEBUG,"libc-cacheflush",__VA_ARGS__) 34 #endif 35 36 /* 37 * Linux historically defines a cacheflush(3) routine for MIPS 38 * with this signature: 39 * int cacheflush(char *addr, int nbytes, int cache); 40 * 41 * Android defines an alternate cacheflush routine which exposes the 42 * ARM system call interface: 43 * int cacheflush (long start, long end, long flags) 44 * 45 * This is an attempt to maintain compatibility between the historical MIPS 46 * usage for software previously ported to MIPS and Android specific 47 * uses of cacheflush() 48 * 49 * Use the gcc __clear_cache builtin if possible. This will generate inline synci 50 * instructions if available or call _flush_cache(start, len, BCACHE) directly 51 */ 52 53 #if defined (__GNUC__) 54 #define GCC_VERSION ((__GNUC__*10000) + __GNUC_MINOR__*100 + __GNUC_PATCHLEVEL__) 55 #endif 56 57 /* This is the Android signature */ 58 int cacheflush (long start, long end, long flags) 59 { 60 if (end < start) { 61 /* 62 * It looks like this is really MIPS style cacheflush call 63 * start => addr 64 * end => nbytes 65 */ 66 #ifdef DEBUG 67 static int warned = 0; 68 if (!warned) { 69 XLOG("called with (start,len) instead of (start,end)"); 70 warned = 1; 71 } 72 #endif 73 end += start; 74 } 75 76 #if !defined(ARCH_MIPS_USE_FLUSHCACHE_SYSCALL) && \ 77 defined(GCC_VERSION) && (GCC_VERSION >= 40300) 78 79 #if (__mips_isa_rev >= 2) && (GCC_VERSION < 40403) 80 /* 81 * Modify "start" and "end" to avoid GCC 4.3.0-4.4.2 bug in 82 * mips_expand_synci_loop that may execute synci one more time. 83 * "start" points to the first byte of the cache line. 84 * "end" points to the last byte of the line before the last cache line. 85 * Because size is always a multiple of 4, this is safe to set 86 * "end" to the last byte. 87 */ 88 { 89 int lineSize; 90 asm("rdhwr %0, $1" : "=r" (lineSize)); 91 start = start & (-lineSize); 92 end = (end & (-lineSize)) - 1; 93 } 94 #endif 95 __builtin___clear_cache((char *)start, (char *)end); 96 #else 97 _flush_cache((char *)start, end-start, BCACHE); 98 #endif 99 return 0; 100 } 101
