Marlin/Marlin/M100_Free_Mem_Chk.cpp
2017-03-31 02:20:20 -05:00

217 lines
7.7 KiB
C++

/**
* 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 <http://www.gnu.org/licenses/>.
*
*/
/**
* 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*);
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.
//
#if ENABLED(M100_FREE_MEMORY_DUMPER) // Disable to remove Dump sub-command
if (code_seen('D')) {
ptr = __brkval ? __brkval : &__bss_end;
//
// 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.
//
SERIAL_ECHOPAIR("\nbss_end : 0x", hex_word((uint16_t)ptr));
ptr = (char*)((uint32_t)ptr & 0xfff0);
sp = top_of_stack();
SERIAL_ECHOLNPAIR("\nStack Pointer : 0x", hex_word((uint16_t)sp));
sp = (char*)((uint32_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
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;
}
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')) {
#if 0
int max_addr = (int) __brkval ? __brkval : &__bss_end;
int max_cnt = 0;
#endif
int block_cnt = 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)));
i += j;
block_cnt++;
}
#if 0
if (j > max_cnt) { // We don't do anything with this information yet
max_cnt = j; // but we do know where the biggest free memory block is.
max_addr = (int) ptr + i;
}
#endif
}
}
if (block_cnt > 1)
SERIAL_ECHOLNPGM("\nMemory Corruption detected in free memory area.");
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 = __brkval ? __brkval : &__bss_end;
SERIAL_ECHOPAIR("\nbss_end : ", ptr);
ptr += 8;
sp = top_of_stack();
SERIAL_ECHOPAIR("\nStack Pointer : ", sp);
SERIAL_ECHOLNPGM("\n");
n = sp - ptr - 64; // -64 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.
ptr = __brkval ? __brkval : &__bss_end; // Repeated M100 with no sub-command will not destroy the
SERIAL_ECHOPAIR("\nbss_end : ", ptr); // state of the initialized free memory pool.
ptr += 8;
sp = top_of_stack();
SERIAL_ECHOPAIR("\nStack Pointer : ", sp);
SERIAL_ECHOLNPGM("\n");
n = sp - ptr - 64; // -64 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 : ", ptr + i);
SERIAL_ECHOPAIR("=", *(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;
}
#endif