/** * Marlin 3D Printer Firmware * Copyright (C) 2016 MarlinFirmware [https://github.com/MarlinFirmware/Marlin] * * Based on Sprinter and grbl. * Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . * */ /** * M100 Free Memory Watcher * * This code watches the free memory block between the bottom of the heap and the top of the stack. * This memory block is initialized and watched via the M100 command. * * M100 I Initializes the free memory block and prints vitals statistics about the area * M100 F Identifies how much of the free memory block remains free and unused. It also * detects and reports any corruption within the free memory block that may have * happened due to errant firmware. * M100 D Does a hex display of the free memory block along with a flag for any errant * data that does not match the expected value. * M100 C x Corrupts x locations within the free memory block. This is useful to check the * correctness of the M100 F and M100 D commands. * * Initial version by Roxy-3D */ #define M100_FREE_MEMORY_DUMPER // Comment out to remove Dump sub-command #define M100_FREE_MEMORY_CORRUPTOR // Comment out to remove Corrupt sub-command #include "Marlin.h" #if ENABLED(M100_FREE_MEMORY_WATCHER) extern char* __brkval; extern size_t __heap_start, __heap_end, __flp; extern char __bss_end; // // Utility functions used by M100 to get its work done. // #include "hex_print_routines.h" char* top_of_stack(); int how_many_E5s_are_here(char*); int free_memory_is_corrupted(); // int not bool!!!! it will tell us how many blocks of // free memory it found. void gcode_M100() { static bool m100_not_initialized = true; char* sp, *ptr; int i, j, n; // // M100 D dumps the free memory block from __brkval to the stack pointer. // malloc() eats memory from the start of the block and the stack grows // up from the bottom of the block. Solid 0xE5's indicate nothing has // used that memory yet. There should not be anything but 0xE5's within // the block of 0xE5's. If there is, that would indicate memory corruption // probably caused by bad pointers. Any unexpected values will be flagged in // the right hand column to help spotting them. // SERIAL_ECHOPAIR("\n__brkval : 0x", hex_word((uint16_t)__brkval) ); SERIAL_ECHOPAIR("\n__bss_end : 0x", hex_word((uint16_t)&__bss_end)); // // With out malloc() we need to be smart and use &__bss_end // ptr = __brkval ? __brkval : &__bss_end; SERIAL_ECHOPAIR("\nstart of free space : 0x", hex_word((uint16_t)ptr)); sp = top_of_stack(); SERIAL_ECHOLNPAIR("\nStack Pointer : 0x", hex_word((uint16_t)sp)); #if ENABLED(M100_FREE_MEMORY_DUMPER) // Disable to remove Dump sub-command if (code_seen('D')) { // // We want to start and end the dump on a nice 16 byte boundry even though // the values we are using are not 16 byte aligned. // ptr = (char*) ((uint16_t) ptr & 0xfff0); sp = (char*) ((uint16_t) sp | 0x000f); n = sp - ptr; // // This is the main loop of the Dump command. // while (ptr < sp) { print_hex_word((uint16_t)ptr); // Print the address SERIAL_CHAR(':'); for (i = 0; i < 16; i++) { // and 16 data bytes if (i==8) SERIAL_CHAR('-'); print_hex_byte(*(ptr + i)); SERIAL_CHAR(' '); } SERIAL_CHAR('|'); // now show where non 0xE5's are for (i = 0; i < 16; i++) SERIAL_CHAR((*(ptr + i) == (char)0xe5) ? ' ' : '?'); SERIAL_EOL; ptr += 16; idle(); } return; } #endif // // M100 F requests the code to return the number of free bytes in the memory pool along with // other vital statistics that define the memory pool. // if (code_seen('F')) { int max_cnt = -1, block_cnt = 0; uint16_t max_addr=0; ptr = __brkval ? __brkval : &__bss_end; sp = top_of_stack(); n = sp - ptr; // Scan through the range looking for the biggest block of 0xE5's we can find for (i = 0; i < n; i++) { if (*(ptr + i) == (char)0xe5) { j = how_many_E5s_are_here(ptr + i); if (j > 8) { SERIAL_ECHOPAIR("Found ", j); SERIAL_ECHOLNPAIR(" bytes free at 0x", hex_word((uint16_t)(ptr + i))); if (j > max_cnt) { max_cnt = j; max_addr = (uint16_t) ptr + i; } i += j; block_cnt++; } } } if (block_cnt > 1) { SERIAL_ECHOLNPGM("\nMemory Corruption detected in free memory area."); SERIAL_ECHOPAIR("\nLargest free block is ", max_cnt); SERIAL_ECHOLNPAIR(" bytes big at 0x", hex_word(max_addr)); } SERIAL_ECHOLNPAIR("free_memory_is_corrupted() = ", free_memory_is_corrupted()); return; } // // M100 C x Corrupts x locations in the free memory pool and reports the locations of the corruption. // This is useful to check the correctness of the M100 D and the M100 F commands. // #if ENABLED(M100_FREE_MEMORY_CORRUPTOR) if (code_seen('C')) { int x = code_value_int(); // x gets the # of locations to corrupt within the memory pool SERIAL_ECHOLNPGM("Corrupting free memory block.\n"); ptr += 8; sp = top_of_stack(); n = sp - ptr - 250; // -250 just to keep us from finding interrupt activity that // has altered the stack. j = n / (x + 1); for (i = 1; i <= x; i++) { *(ptr + (i * j)) = i; SERIAL_ECHOPAIR("\nCorrupting address: 0x", hex_word((uint16_t)(ptr + i * j))); } SERIAL_ECHOLNPGM("\n"); return; } #endif // // M100 I Initializes the free memory pool so it can be watched and prints vital // statistics that define the free memory pool. // if (m100_not_initialized || code_seen('I')) { // If no sub-command is specified, the first time SERIAL_ECHOLNPGM("Initializing free memory block.\n"); // this happens, it will Initialize. // Repeated M100 with no sub-command will not destroy the // state of the initialized free memory pool. ptr += 8; SERIAL_ECHOLNPGM("\n"); n = sp - ptr - 250; // -250 just to keep us from finding interrupt activity that // has altered the stack. SERIAL_ECHO(n); SERIAL_ECHOLNPGM(" bytes of memory initialized.\n"); for (i = 0; i < n; i++) *(ptr + i) = (char)0xe5; for (i = 0; i < n; i++) { if (*(ptr + i) != (char)0xe5) { SERIAL_ECHOPAIR("? address : ", hex_word(ptr+i) ); SERIAL_ECHOPAIR("=", hex_byte(*(ptr + i)) ); SERIAL_ECHOLNPGM("\n"); } } m100_not_initialized = false; return; } return; } // top_of_stack() returns the location of a variable on its stack frame. The value returned is above // the stack once the function returns to the caller. char* top_of_stack() { char x; return &x + 1; // x is pulled on return; } // how_many_E5s_are_here() is a utility function to easily find out how many 0xE5's are // at the specified location. Having this logic as a function simplifies the search code. // int how_many_E5s_are_here(char* p) { int n; for (n = 0; n < 32000; n++) { if (*(p + n) != (char)0xe5) return n - 1; } return -1; } int free_memory_is_corrupted() { char *sp, *ptr; int block_cnt = 0, i, j, n; ptr = __brkval ? __brkval : &__bss_end; sp = top_of_stack(); n = sp - ptr; // Scan through the range looking for the biggest block of 0xE5's we can find for (i = 0; i < n; i++) { if (*(ptr + i) == (char)0xe5) { j = how_many_E5s_are_here(ptr + i); if (j > 8) { // SERIAL_ECHOPAIR("Found ", j); // SERIAL_ECHOLNPAIR(" bytes free at 0x", hex_word((uint16_t)(ptr + i))); i += j; block_cnt++; } } } // if (block_cnt > 1) { // SERIAL_ECHOLNPGM("\nMemory Corruption detected in free memory area."); // SERIAL_ECHOLNPAIR("\nLargest free block is ", max_cnt); // } return block_cnt; } #endif