mbed library sources. Supersedes mbed-src.
Fork of mbed by
Diff: targets/cmsis/TARGET_NORDIC/TARGET_MCU_NRF51822/cmsis_nvic.c
- Revision:
- 0:9b334a45a8ff
- Child:
- 144:ef7eb2e8f9f7
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/cmsis/TARGET_NORDIC/TARGET_MCU_NRF51822/cmsis_nvic.c Thu Oct 01 15:25:22 2015 +0300 @@ -0,0 +1,103 @@ +/* mbed Microcontroller Library + * CMSIS-style functionality to support dynamic vectors + ******************************************************************************* + * Copyright (c) 2011 ARM Limited. All rights reserved. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * 3. Neither the name of ARM Limited nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + ******************************************************************************* + */ +#include "cmsis_nvic.h" + +/* In the M0, there is no VTOR. In the LPC range such as the LPC11U, + * whilst the vector table may only be something like 48 entries (192 bytes, 0xC0), + * the SYSMEMREMAP register actually remaps the memory from 0x10000000-0x100001FF + * to adress 0x0-0x1FF. In this case, RAM can be addressed at both 0x10000000 and 0x0 + * + * If we just copy the vectors to RAM and switch the SYSMEMMAP, any accesses to FLASH + * above the vector table before 0x200 will actually go to RAM. So we need to provide + * a solution where the compiler gets the right results based on the memory map + * + * Option 1 - We allocate and copy 0x200 of RAM rather than just the table + * - const data and instructions before 0x200 will be copied to and fetched/exec from RAM + * - RAM overhead: 0x200 - 0xC0 = 320 bytes, FLASH overhead: 0 + * + * Option 2 - We pad the flash to 0x200 to ensure the compiler doesn't allocate anything there + * - No flash accesses will go to ram, as there will be nothing there + * - RAM only needs to be allocated for the vectors, as all other ram addresses are normal + * - RAM overhead: 0, FLASH overhead: 320 bytes + * + * Option 2 is the one to go for, as RAM is the most valuable resource + */ + + +#define NVIC_RAM_VECTOR_ADDRESS (0x10000000) // Location of vectors in RAM +#define NVIC_FLASH_VECTOR_ADDRESS (0x0) // Initial vector position in flash +/* +void NVIC_SetVector(IRQn_Type IRQn, uint32_t vector) { + uint32_t *vectors = (uint32_t*)SCB->VTOR; + uint32_t i; + + // Copy and switch to dynamic vectors if the first time called + if (SCB->VTOR == NVIC_FLASH_VECTOR_ADDRESS) { + uint32_t *old_vectors = vectors; + vectors = (uint32_t*)NVIC_RAM_VECTOR_ADDRESS; + for (i=0; i<NVIC_NUM_VECTORS; i++) { + vectors[i] = old_vectors[i]; + } + SCB->VTOR = (uint32_t)NVIC_RAM_VECTOR_ADDRESS; + } + vectors[IRQn + 16] = vector; +} + +uint32_t NVIC_GetVector(IRQn_Type IRQn) { + uint32_t *vectors = (uint32_t*)SCB->VTOR; + return vectors[IRQn + 16]; +}*/ + +void NVIC_SetVector(IRQn_Type IRQn, uint32_t vector) { + // int i; + // Space for dynamic vectors, initialised to allocate in R/W + static volatile uint32_t* vectors = (uint32_t*)NVIC_RAM_VECTOR_ADDRESS; + /* + // Copy and switch to dynamic vectors if first time called + if((LPC_SYSCON->SYSMEMREMAP & 0x3) != 0x1) { + uint32_t *old_vectors = (uint32_t *)0; // FLASH vectors are at 0x0 + for(i = 0; i < NVIC_NUM_VECTORS; i++) { + vectors[i] = old_vectors[i]; + } + LPC_SYSCON->SYSMEMREMAP = 0x1; // Remaps 0x0-0x1FF FLASH block to RAM block + }*/ + + // Set the vector + vectors[IRQn + 16] = vector; +} + +uint32_t NVIC_GetVector(IRQn_Type IRQn) { + // We can always read vectors at 0x0, as the addresses are remapped + uint32_t *vectors = (uint32_t*)0; + + // Return the vector + return vectors[IRQn + 16]; +}