| /* |
| * Copyright (c) 2014 Wind River Systems, Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| /** |
| * @file |
| * @brief Full C support initialization |
| * |
| * |
| * Initialization of full C support: zero the .bss, copy the .data if XIP, |
| * call _Cstart(). |
| * |
| * Stack is available in this module, but not the global data/bss until their |
| * initialization is performed. |
| */ |
| |
| #include <stdint.h> |
| #include <toolchain.h> |
| #include <linker-defs.h> |
| |
| /** |
| * |
| * @brief Clear BSS |
| * |
| * This routine clears the BSS region, so all bytes are 0. |
| * |
| * @return N/A |
| */ |
| |
| static void bssZero(void) |
| { |
| volatile uint32_t *pBSS = (uint32_t *)&__bss_start; |
| unsigned int n; |
| |
| for (n = 0; n < (unsigned int)&__bss_num_words; n++) { |
| pBSS[n] = 0; |
| } |
| } |
| |
| /** |
| * |
| * @brief Copy the data section from ROM to RAM |
| * |
| * This routine copies the data section from ROM to RAM. |
| * |
| * @return N/A |
| */ |
| |
| #ifdef CONFIG_XIP |
| static void dataCopy(void) |
| { |
| volatile uint32_t *pROM = (uint32_t *)&__data_rom_start; |
| volatile uint32_t *pRAM = (uint32_t *)&__data_ram_start; |
| unsigned int n; |
| |
| for (n = 0; n < (unsigned int)&__data_num_words; n++) { |
| pRAM[n] = pROM[n]; |
| } |
| } |
| #else |
| static void dataCopy(void) |
| { |
| } |
| #endif |
| |
| extern FUNC_NORETURN void _Cstart(void); |
| /** |
| * |
| * @brief Prepare to and run C code |
| * |
| * This routine prepares for the execution of and runs C code. |
| * |
| * @return N/A |
| */ |
| |
| void _PrepC(void) |
| { |
| bssZero(); |
| dataCopy(); |
| _Cstart(); |
| CODE_UNREACHABLE; |
| } |