1 /* 2 * Copyright (c) 2014 Google, Inc. 3 * 4 * SPDX-License-Identifier: GPL-2.0+ 5 */ 6 7 #ifndef __IOTRACE_H 8 #define __IOTRACE_H 9 10 #include <linux/types.h> 11 12 /* 13 * This file is designed to be included in arch/<arch>/include/asm/io.h. 14 * It redirects all IO access through a tracing/checksumming feature for 15 * testing purposes. 16 */ 17 18 #if defined(CONFIG_IO_TRACE) && !defined(IOTRACE_IMPL) && \ 19 !defined(CONFIG_SPL_BUILD) 20 21 #undef readl 22 #define readl(addr) iotrace_readl((const void *)(addr)) 23 24 #undef writel 25 #define writel(val, addr) iotrace_writel(val, (const void *)(addr)) 26 27 #undef readw 28 #define readw(addr) iotrace_readw((const void *)(addr)) 29 30 #undef writew 31 #define writew(val, addr) iotrace_writew(val, (const void *)(addr)) 32 33 #undef readb 34 #define readb(addr) iotrace_readb((const void *)(addr)) 35 36 #undef writeb 37 #define writeb(val, addr) iotrace_writeb(val, (const void *)(addr)) 38 39 #endif 40 41 /* Tracing functions which mirror their io.h counterparts */ 42 u32 iotrace_readl(const void *ptr); 43 void iotrace_writel(ulong value, const void *ptr); 44 u16 iotrace_readw(const void *ptr); 45 void iotrace_writew(ulong value, const void *ptr); 46 u8 iotrace_readb(const void *ptr); 47 void iotrace_writeb(ulong value, const void *ptr); 48 49 /** 50 * iotrace_reset_checksum() - Reset the iotrace checksum 51 */ 52 void iotrace_reset_checksum(void); 53 54 /** 55 * iotrace_get_checksum() - Get the current checksum value 56 * 57 * @return currect checksum value 58 */ 59 u32 iotrace_get_checksum(void); 60 61 /** 62 * iotrace_set_enabled() - Set whether iotracing is enabled or not 63 * 64 * This controls whether the checksum is updated and a trace record added 65 * for each I/O access. 66 * 67 * @enable: true to enable iotracing, false to disable 68 */ 69 void iotrace_set_enabled(int enable); 70 71 /** 72 * iotrace_get_enabled() - Get whether iotracing is enabled or not 73 * 74 * @return true if enabled, false if disabled 75 */ 76 int iotrace_get_enabled(void); 77 78 /** 79 * iotrace_set_buffer() - Set position and size of iotrace buffer 80 * 81 * Defines where the iotrace buffer goes, and resets the output pointer to 82 * the start of the buffer. 83 * 84 * The buffer can be 0 size in which case the checksum is updated but no 85 * trace records are writen. If the buffer is exhausted, the offset will 86 * continue to increase but not new data will be written. 87 * 88 * @start: Start address of buffer 89 * @size: Size of buffer in bytes 90 */ 91 void iotrace_set_buffer(ulong start, ulong size); 92 93 /** 94 * iotrace_get_buffer() - Get buffer information 95 * 96 * @start: Returns start address of buffer 97 * @size: Returns size of buffer in bytes 98 * @offset: Returns the byte offset where the next output trace record will 99 * @count: Returns the number of trace records recorded 100 * be written (or would be if the buffer was large enough) 101 */ 102 void iotrace_get_buffer(ulong *start, ulong *size, ulong *offset, ulong *count); 103 104 #endif /* __IOTRACE_H */ 105