diff --git a/Marlin/src/HAL/HAL_DUE/InterruptVectors_Due.cpp b/Marlin/src/HAL/HAL_DUE/InterruptVectors_Due.cpp new file mode 100644 index 0000000000..0a46776110 --- /dev/null +++ b/Marlin/src/HAL/HAL_DUE/InterruptVectors_Due.cpp @@ -0,0 +1,95 @@ +/** + * 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 . + * + */ + +/** + * InterruptVectors_Due.cpp - This module relocates the Interrupt vector table to SRAM, + * allowing to register new interrupt handlers at runtime. Specially valuable and needed + * because Arduino runtime allocates some interrupt handlers that we NEED to override to + * properly support extended functionality, as for example, USB host or USB device (MSD, MTP) + * and custom serial port handlers, and we don't actually want to modify and/or recompile the + * Arduino runtime. We just want to run as much as possible on Stock Arduino + * + * Copyright (c) 2017 Eduardo José Tagle. All right reserved + */ +#ifdef ARDUINO_ARCH_SAM + +#include "HAL_Due.h" +#include "InterruptVectors_Due.h" + +/* The relocated Exception/Interrupt Table - Must be aligned to 128bytes, + as bits 0-6 on VTOR register are reserved and must be set to 0 */ +__attribute__ ((aligned(128))) +static DeviceVectors ram_tab = { NULL }; + +/** + * This function checks if the exception/interrupt table is already in SRAM or not. + * If it is not, then it copies the ROM table to the SRAM and relocates the table + * by reprogramming the NVIC registers + */ +static pfnISR_Handler* get_relocated_table_addr(void) { + // Get the address of the interrupt/exception table + uint32_t isrtab = SCB->VTOR; + + // If already relocated, we are done! + if (isrtab >= IRAM0_ADDR) + return (pfnISR_Handler*)isrtab; + + // Get the address of the table stored in FLASH + const pfnISR_Handler* romtab = (const pfnISR_Handler*)isrtab; + + // Copy it to SRAM + memcpy(&ram_tab, romtab, sizeof(ram_tab)); + + // Disable global interrupts + CRITICAL_SECTION_START; + + // Set the vector table base address to the SRAM copy + SCB->VTOR = (uint32_t)(&ram_tab); + + // Reenable interrupts + CRITICAL_SECTION_END; + + // Return the address of the table + return (pfnISR_Handler*)(&ram_tab); +} + +pfnISR_Handler install_isr(IRQn_Type irq, pfnISR_Handler newHandler) { + // Get the address of the relocated table + const pfnISR_Handler *isrtab = get_relocated_table_addr(); + + // Disable global interrupts + CRITICAL_SECTION_START; + + // Get the original handler + pfnISR_Handler oldHandler = isrtab[irq + 16]; + + // Install the new one + isrtab[irq + 16] = newHandler; + + // Reenable interrupts + CRITICAL_SECTION_END; + + // Return the original one + return oldHandler; +} + +#endif diff --git a/Marlin/src/HAL/HAL_DUE/InterruptVectors_Due.h b/Marlin/src/HAL/HAL_DUE/InterruptVectors_Due.h new file mode 100644 index 0000000000..efc63de25d --- /dev/null +++ b/Marlin/src/HAL/HAL_DUE/InterruptVectors_Due.h @@ -0,0 +1,52 @@ +/** + * 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 . + * + */ + +/** + * InterruptVectors_Due.h + * + * Copyright (c) 2017 Eduardo José Tagle. All right reserved + * + * This module relocates the Interrupt vector table to SRAM, allowing new + * interrupt handlers to be added at runtime. This is required because the + * Arduino runtime steals interrupt handlers that Marlin MUST use to support + * extended functionality such as USB hosts and USB devices (MSD, MTP) and + * custom serial port handlers. Rather than modifying and/or recompiling the + * Arduino runtime, We just want to run as much as possible on Stock Arduino. + * + * Copyright (c) 2017 Eduardo José Tagle. All right reserved + */ + +#ifndef INTERRUPTVECTORS_DUE_H +#define INTERRUPTVECTORS_DUE_H + +#include "../../inc/MarlinConfig.h" + +#ifdef ARDUINO_ARCH_SAM + +// ISR handler type +typedef void (*pfnISR_Handler)(void); + +// Install a new interrupt vector handler for the given irq, returning the old one +pfnISR_Handler install_isr(IRQn_Type irq, pfnISR_Handler newHandler); + +#endif // ARDUINO_ARCH_SAM +#endif // INTERRUPTVECTORS_DUE_H