diff --git a/README b/README index 7129df822c..d0723701c8 100644 --- a/README +++ b/README @@ -1000,6 +1000,7 @@ The following options need to be configured: CONFIG_CMD_IMLS List all images found in NOR flash CONFIG_CMD_IMLS_NAND * List all images found in NAND flash CONFIG_CMD_IMMAP * IMMR dump support + CONFIG_CMD_IOTRACE * I/O tracing for debugging CONFIG_CMD_IMPORTENV * import an environment CONFIG_CMD_INI * import data from an ini file into the env CONFIG_CMD_IRQ * irqinfo @@ -1171,6 +1172,28 @@ The following options need to be configured: Note that if the GPIO device uses I2C, then the I2C interface must also be configured. See I2C Support, below. +- I/O tracing: + When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O + accesses and can checksum them or write a list of them out + to memory. See the 'iotrace' command for details. This is + useful for testing device drivers since it can confirm that + the driver behaves the same way before and after a code + change. Currently this is supported on sandbox and arm. To + add support for your architecture, add '#include ' + to the bottom of arch//include/asm/io.h and test. + + Example output from the 'iotrace stats' command is below. + Note that if the trace buffer is exhausted, the checksum will + still continue to operate. + + iotrace is enabled + Start: 10000000 (buffer start address) + Size: 00010000 (buffer size) + Offset: 00000120 (current buffer offset) + Output: 10000120 (start + offset) + Count: 00000018 (number of trace records) + CRC32: 9526fb66 (CRC32 of all trace records) + - Timestamp Support: When CONFIG_TIMESTAMP is selected, the timestamp diff --git a/common/Makefile b/common/Makefile index f6cd98012a..de5cce86cc 100644 --- a/common/Makefile +++ b/common/Makefile @@ -114,6 +114,7 @@ obj-$(CONFIG_CMD_FUSE) += cmd_fuse.o obj-$(CONFIG_CMD_GETTIME) += cmd_gettime.o obj-$(CONFIG_CMD_GPIO) += cmd_gpio.o obj-$(CONFIG_CMD_I2C) += cmd_i2c.o +obj-$(CONFIG_CMD_IOTRACE) += cmd_iotrace.o obj-$(CONFIG_CMD_HASH) += cmd_hash.o obj-$(CONFIG_CMD_IDE) += cmd_ide.o obj-$(CONFIG_CMD_IMMAP) += cmd_immap.o @@ -261,6 +262,7 @@ obj-$(CONFIG_ANDROID_BOOT_IMAGE) += image-android.o obj-$(CONFIG_OF_LIBFDT) += image-fdt.o obj-$(CONFIG_FIT) += image-fit.o obj-$(CONFIG_FIT_SIGNATURE) += image-sig.o +obj-$(CONFIG_IO_TRACE) += iotrace.o obj-y += memsize.o obj-y += stdio.o diff --git a/common/cmd_iotrace.c b/common/cmd_iotrace.c new file mode 100644 index 0000000000..f54276d2f5 --- /dev/null +++ b/common/cmd_iotrace.c @@ -0,0 +1,73 @@ +/* + * Copyright (c) 2014 Google, Inc + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include +#include +#include + +static void do_print_stats(void) +{ + ulong start, size, offset, count; + + printf("iotrace is %sabled\n", iotrace_get_enabled() ? "en" : "dis"); + iotrace_get_buffer(&start, &size, &offset, &count); + printf("Start: %08lx\n", start); + printf("Size: %08lx\n", size); + printf("Offset: %08lx\n", offset); + printf("Output: %08lx\n", start + offset); + printf("Count: %08lx\n", count); + printf("CRC32: %08lx\n", (ulong)iotrace_get_checksum()); +} + +static int do_set_buffer(int argc, char * const argv[]) +{ + ulong addr = 0, size = 0; + + if (argc == 2) { + addr = simple_strtoul(*argv++, NULL, 16); + size = simple_strtoul(*argv++, NULL, 16); + } else if (argc != 0) { + return CMD_RET_USAGE; + } + + iotrace_set_buffer(addr, size); + + return 0; +} + +int do_iotrace(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) +{ + const char *cmd = argc < 2 ? NULL : argv[1]; + + if (!cmd) + return cmd_usage(cmdtp); + switch (*cmd) { + case 'b': + return do_set_buffer(argc - 2, argv + 2); + case 'p': + iotrace_set_enabled(0); + break; + case 'r': + iotrace_set_enabled(1); + break; + case 's': + do_print_stats(); + break; + default: + return CMD_RET_USAGE; + } + + return 0; +} + +U_BOOT_CMD( + iotrace, 4, 1, do_iotrace, + "iotrace utility commands", + "stats - display iotrace stats\n" + "iotrace buffer
- set iotrace buffer\n" + "iotrace pause - pause tracing\n" + "iotrace resume - resume tracing" +); diff --git a/common/iotrace.c b/common/iotrace.c new file mode 100644 index 0000000000..ced426ea5c --- /dev/null +++ b/common/iotrace.c @@ -0,0 +1,169 @@ +/* + * Copyright (c) 2014 Google, Inc. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#define IOTRACE_IMPL + +#include +#include + +DECLARE_GLOBAL_DATA_PTR; + +/* Support up to the machine word length for now */ +typedef ulong iovalue_t; + +enum iotrace_flags { + IOT_8 = 0, + IOT_16, + IOT_32, + + IOT_READ = 0 << 3, + IOT_WRITE = 1 << 3, +}; + +/** + * struct iotrace_record - Holds a single I/O trace record + * + * @flags: I/O access type + * @addr: Address of access + * @value: Value written or read + */ +struct iotrace_record { + enum iotrace_flags flags; + phys_addr_t addr; + iovalue_t value; +}; + +/** + * struct iotrace - current trace status and checksum + * + * @start: Start address of iotrace buffer + * @size: Size of iotrace buffer in bytes + * @offset: Current write offset into iotrace buffer + * @crc32: Current value of CRC chceksum of trace records + * @enabled: true if enabled, false if disabled + */ +static struct iotrace { + ulong start; + ulong size; + ulong offset; + u32 crc32; + bool enabled; +} iotrace; + +static void add_record(int flags, const void *ptr, ulong value) +{ + struct iotrace_record srec, *rec = &srec; + + /* + * We don't support iotrace before relocation. Since the trace buffer + * is set up by a command, it can't be enabled at present. To change + * this we would need to set the iotrace buffer at build-time. See + * lib/trace.c for how this might be done if you are interested. + */ + if (!(gd->flags & GD_FLG_RELOC) || !iotrace.enabled) + return; + + /* Store it if there is room */ + if (iotrace.offset + sizeof(*rec) < iotrace.size) { + rec = (struct iotrace_record *)map_sysmem( + iotrace.start + iotrace.offset, + sizeof(value)); + } + + rec->flags = flags; + rec->addr = map_to_sysmem(ptr); + rec->value = value; + + /* Update our checksum */ + iotrace.crc32 = crc32(iotrace.crc32, (unsigned char *)rec, + sizeof(*rec)); + + iotrace.offset += sizeof(struct iotrace_record); +} + +u32 iotrace_readl(const void *ptr) +{ + u32 v; + + v = readl(ptr); + add_record(IOT_32 | IOT_READ, ptr, v); + + return v; +} + +void iotrace_writel(ulong value, const void *ptr) +{ + add_record(IOT_32 | IOT_WRITE, ptr, value); + writel(value, ptr); +} + +u16 iotrace_readw(const void *ptr) +{ + u32 v; + + v = readw(ptr); + add_record(IOT_16 | IOT_READ, ptr, v); + + return v; +} + +void iotrace_writew(ulong value, const void *ptr) +{ + add_record(IOT_16 | IOT_WRITE, ptr, value); + writew(value, ptr); +} + +u8 iotrace_readb(const void *ptr) +{ + u32 v; + + v = readb(ptr); + add_record(IOT_8 | IOT_READ, ptr, v); + + return v; +} + +void iotrace_writeb(ulong value, const void *ptr) +{ + add_record(IOT_8 | IOT_WRITE, ptr, value); + writeb(value, ptr); +} + +void iotrace_reset_checksum(void) +{ + iotrace.crc32 = 0; +} + +u32 iotrace_get_checksum(void) +{ + return iotrace.crc32; +} + +void iotrace_set_enabled(int enable) +{ + iotrace.enabled = enable; +} + +int iotrace_get_enabled(void) +{ + return iotrace.enabled; +} + +void iotrace_set_buffer(ulong start, ulong size) +{ + iotrace.start = start; + iotrace.size = size; + iotrace.offset = 0; + iotrace.crc32 = 0; +} + +void iotrace_get_buffer(ulong *start, ulong *size, ulong *offset, ulong *count) +{ + *start = iotrace.start; + *size = iotrace.size; + *offset = iotrace.offset; + *count = iotrace.offset / sizeof(struct iotrace_record); +} diff --git a/include/iotrace.h b/include/iotrace.h new file mode 100644 index 0000000000..9bd1f167ab --- /dev/null +++ b/include/iotrace.h @@ -0,0 +1,104 @@ +/* + * Copyright (c) 2014 Google, Inc. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef __IOTRACE_H +#define __IOTRACE_H + +#include + +/* + * This file is designed to be included in arch//include/asm/io.h. + * It redirects all IO access through a tracing/checksumming feature for + * testing purposes. + */ + +#if defined(CONFIG_IO_TRACE) && !defined(IOTRACE_IMPL) && \ + !defined(CONFIG_SPL_BUILD) + +#undef readl +#define readl(addr) iotrace_readl((const void *)(addr)) + +#undef writel +#define writel(val, addr) iotrace_writel(val, (const void *)(addr)) + +#undef readw +#define readw(addr) iotrace_readw((const void *)(addr)) + +#undef writew +#define writew(val, addr) iotrace_writew(val, (const void *)(addr)) + +#undef readb +#define readb(addr) iotrace_readb((const void *)(addr)) + +#undef writeb +#define writeb(val, addr) iotrace_writeb(val, (const void *)(addr)) + +#endif + +/* Tracing functions which mirror their io.h counterparts */ +u32 iotrace_readl(const void *ptr); +void iotrace_writel(ulong value, const void *ptr); +u16 iotrace_readw(const void *ptr); +void iotrace_writew(ulong value, const void *ptr); +u8 iotrace_readb(const void *ptr); +void iotrace_writeb(ulong value, const void *ptr); + +/** + * iotrace_reset_checksum() - Reset the iotrace checksum + */ +void iotrace_reset_checksum(void); + +/** + * iotrace_get_checksum() - Get the current checksum value + * + * @return currect checksum value + */ +u32 iotrace_get_checksum(void); + +/** + * iotrace_set_enabled() - Set whether iotracing is enabled or not + * + * This controls whether the checksum is updated and a trace record added + * for each I/O access. + * + * @enable: true to enable iotracing, false to disable + */ +void iotrace_set_enabled(int enable); + +/** + * iotrace_get_enabled() - Get whether iotracing is enabled or not + * + * @return true if enabled, false if disabled + */ +int iotrace_get_enabled(void); + +/** + * iotrace_set_buffer() - Set position and size of iotrace buffer + * + * Defines where the iotrace buffer goes, and resets the output pointer to + * the start of the buffer. + * + * The buffer can be 0 size in which case the checksum is updated but no + * trace records are writen. If the buffer is exhausted, the offset will + * continue to increase but not new data will be written. + * + * @start: Start address of buffer + * @size: Size of buffer in bytes + */ +void iotrace_set_buffer(ulong start, ulong size); + +/** + * iotrace_get_buffer() - Get buffer information + * + * @start: Returns start address of buffer + * @size: Returns size of buffer in bytes + * @offset: Returns the byte offset where the next output trace record will + * @count: Returns the number of trace records recorded + * be written (or would be if the buffer was large enough) + */ +void iotrace_get_buffer(ulong *start, ulong *size, ulong *offset, ulong *count); + +#endif /* __IOTRACE_H */