diff options
Diffstat (limited to 'Marlin/src/HAL/shared/backtrace/unwarm.cpp')
| -rw-r--r-- | Marlin/src/HAL/shared/backtrace/unwarm.cpp | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/Marlin/src/HAL/shared/backtrace/unwarm.cpp b/Marlin/src/HAL/shared/backtrace/unwarm.cpp new file mode 100644 index 0000000..adbcca6 --- /dev/null +++ b/Marlin/src/HAL/shared/backtrace/unwarm.cpp @@ -0,0 +1,175 @@ +/*************************************************************************** + * ARM Stack Unwinder, Michael.McTernan.2001@cs.bris.ac.uk + * Updated, adapted and several bug fixes on 2018 by Eduardo José Tagle + * + * This program is PUBLIC DOMAIN. + * This means that there is no copyright and anyone is able to take a copy + * for free and use it as they wish, with or without modifications, and in + * any context, commercially or otherwise. The only limitation is that I + * don't guarantee that the software is fit for any purpose or accept any + * liability for its use or misuse - this software is without warranty. + *************************************************************************** + * File Description: Utility functions and glue for ARM unwinding sub-modules. + **************************************************************************/ + +#if defined(__arm__) || defined(__thumb__) + +#define MODULE_NAME "UNWARM" + +#include <stdint.h> +#include <stdio.h> +#include <stdarg.h> +#include <string.h> +#include "unwarm.h" +#include "unwarmmem.h" + +#ifdef UNW_DEBUG + +/** + * Printf wrapper. + * This is used such that alternative outputs for any output can be selected + * by modification of this wrapper function. + */ +void UnwPrintf(const char *format, ...) { + va_list args; + + va_start( args, format ); + vprintf(format, args ); +} +#endif + +/** + * Invalidate all general purpose registers. + */ +void UnwInvalidateRegisterFile(RegData *regFile) { + uint8_t t = 0; + do { + regFile[t].o = REG_VAL_INVALID; + t++; + } while (t < 13); +} + + +/** + * Initialize the data used for unwinding. + */ +void UnwInitState(UnwState * const state, /**< Pointer to structure to fill. */ + const UnwindCallbacks *cb, /**< Callbacks. */ + void *rptData, /**< Data to pass to report function. */ + uint32_t pcValue, /**< PC at which to start unwinding. */ + uint32_t spValue) { /**< SP at which to start unwinding. */ + + UnwInvalidateRegisterFile(state->regData); + + /* Store the pointer to the callbacks */ + state->cb = cb; + state->reportData = rptData; + + /* Setup the SP and PC */ + state->regData[13].v = spValue; + state->regData[13].o = REG_VAL_FROM_CONST; + state->regData[15].v = pcValue; + state->regData[15].o = REG_VAL_FROM_CONST; + + UnwPrintd3("\nInitial: PC=0x%08x SP=0x%08x\n", pcValue, spValue); + + /* Invalidate all memory addresses */ + memset(state->memData.used, 0, sizeof(state->memData.used)); +} + +// Detect if function names are available +static int __attribute__ ((noinline)) has_function_names() { + uint32_t flag_word = ((uint32_t*)(((uint32_t)(&has_function_names)) & (-4))) [-1]; + return ((flag_word & 0xFF000000) == 0xFF000000) ? 1 : 0; +} + +/** + * Call the report function to indicate some return address. + * This returns the value of the report function, which if true + * indicates that unwinding may continue. + */ +bool UnwReportRetAddr(UnwState * const state, uint32_t addr) { + + UnwReport entry; + + // We found two acceptable values. + entry.name = nullptr; + entry.address = addr & 0xFFFFFFFE; // Remove Thumb bit + entry.function = 0; + + // If there are function names, try to solve name + if (has_function_names()) { + + // Lets find the function name, if possible + + // Align address to 4 bytes + uint32_t pf = addr & (-4); + + // Scan backwards until we find the function name + uint32_t v; + while (state->cb->readW(pf-4,&v)) { + + // Check if name descriptor is valid + if ((v & 0xFFFFFF00) == 0xFF000000 && (v & 0xFF) > 1) { + // Assume the name was found! + entry.name = ((const char*)pf) - 4 - (v & 0xFF); + entry.function = pf; + break; + } + + // Go backwards to the previous word + pf -= 4; + } + } + + /* Cast away const from reportData. + * The const is only to prevent the unw module modifying the data. + */ + return state->cb->report((void *)state->reportData, &entry); +} + + +/** + * Write some register to memory. + * This will store some register and meta data onto the virtual stack. + * The address for the write + * \param state [in/out] The unwinding state. + * \param wAddr [in] The address at which to write the data. + * \param reg [in] The register to store. + * \return true if the write was successful, false otherwise. + */ +bool UnwMemWriteRegister(UnwState * const state, const uint32_t addr, const RegData * const reg) { + return UnwMemHashWrite(&state->memData, addr, reg->v, M_IsOriginValid(reg->o)); +} + +/** + * Read a register from memory. + * This will read a register from memory, and setup the meta data. + * If the register has been previously written to memory using + * UnwMemWriteRegister, the local hash will be used to return the + * value while respecting whether the data was valid or not. If the + * register was previously written and was invalid at that point, + * REG_VAL_INVALID will be returned in *reg. + * \param state [in] The unwinding state. + * \param addr [in] The address to read. + * \param reg [out] The result, containing the data value and the origin + * which will be REG_VAL_FROM_MEMORY, or REG_VAL_INVALID. + * \return true if the address could be read and *reg has been filled in. + * false is the data could not be read. + */ +bool UnwMemReadRegister(UnwState * const state, const uint32_t addr, RegData * const reg) { + bool tracked; + + // Check if the value can be found in the hash + if (UnwMemHashRead(&state->memData, addr, ®->v, &tracked)) { + reg->o = tracked ? REG_VAL_FROM_MEMORY : REG_VAL_INVALID; + return true; + } + else if (state->cb->readW(addr, ®->v)) { // Not in the hash, so read from real memory + reg->o = REG_VAL_FROM_MEMORY; + return true; + } + else return false; // Not in the hash, and failed to read from memory +} + +#endif // __arm__ || __thumb__ |