/** * Copyright (c) 2016 - 2019, Nordic Semiconductor ASA * * 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, except as embedded into a Nordic * Semiconductor ASA integrated circuit in a product or a software update for * such product, 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 Nordic Semiconductor ASA nor the names of its * contributors may be used to endorse or promote products derived from this * software without specific prior written permission. * * 4. This software, with or without modification, must only be used with a * Nordic Semiconductor ASA integrated circuit. * * 5. Any software provided in binary form under this license must not be reverse * engineered, decompiled, modified and/or disassembled. * * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA 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 #include #include "nrf_svc_function.h" #include "nrf_error.h" //lint -esym(526, svc_dataBase) -esym(526, svc_dataLimit) NRF_SECTION_DEF(svc_data, const nrf_svc_func_t); #define SVC_DATA_SECTION_ITEM_GET(i) NRF_SECTION_ITEM_GET(svc_data, nrf_svc_func_reg_t, (i)) #define SVC_DATA_SECTION_ITEM_COUNT NRF_SECTION_ITEM_COUNT(svc_data, nrf_svc_func_reg_t) #ifdef __GNUC__ // Prevent GCC from removing this function (called from assembly branch) void nrf_svc_handler_c(uint32_t* p_svc_args) __attribute__((used)); #endif /**@brief Function for handling second stage of Supervisor Calls (SVC). * * @details The function will use loop through the registered svc functions stored * in the named section "svc_data" and will call the registered function * if the svn_num corresponds with the registration. * * @param[in] p_svc_args Argument list for the SVC. * * @return This function returns by updating p_svc_arsg[0]. This will be reported back to the caller of SVC * @ref NRF_ERROR_SVC_HANDLER_MISSING is returned if no SVC handler is implemented for the * provided svc_num. */ void nrf_svc_handler_c(uint32_t* p_svc_args) { uint32_t const num_funcs = SVC_DATA_SECTION_ITEM_COUNT; bool handled = false; uint8_t const svc_num = ((uint8_t *)p_svc_args[6])[-2]; uint32_t svci_num = NRF_SVCI_SVC_NUM_INVALID; if (svc_num == NRF_SVCI_SVC_NUM) { // load the stacked R12 as the svci_num svci_num = p_svc_args[4]; } for (uint32_t i = 0; i < num_funcs; i++) { nrf_svc_func_reg_t const * func_reg = SVC_DATA_SECTION_ITEM_GET(i); if (func_reg->svc_num != svc_num) { continue; } if (svci_num != NRF_SVCI_SVC_NUM_INVALID && func_reg->svci_num != svci_num) { continue; } // Return value is placed in R0 p_svc_args[0] = func_reg->func_ptr(p_svc_args[0], p_svc_args[1], p_svc_args[2], p_svc_args[3]); handled = true; break; } if (handled == false) { // Return value is placed in R0 p_svc_args[0] = NRF_ERROR_SVC_HANDLER_MISSING; } } /**@brief Function for handling the first stage of Supervisor Calls (SVC) in assembly. * * @details The function will use the link register (LR) to determine the stack (PSP or MSP) to be * used and then decode the SVC number afterwards. After decoding the SVC number, * @ref C_SVC_Handler is called for further processing of the SVC. */ #if defined ( __CC_ARM ) __ASM void SVC_Handler(void) { tst lr, #4 ; Test bit 2 of EXT_RETURN to see if MSP or PSP is used ite eq ; mrseq r0, MSP ; If equal, copy stack pointer from MSP mrsne r0, PSP ; If not equal, copy stack pointer from PSP B __cpp(nrf_svc_handler_c) ; Call C-implementation of handler. Exception stack frame in R0 ALIGN 4 ; Protect with alignment } #elif defined ( __GNUC__ ) void __attribute__((naked)) SVC_Handler(void) { __ASM volatile ( "tst lr, #4\t\n" // Test bit 2 of EXT_RETURN to see if MSP or PSP is used "ite eq\t\n" // "mrseq r0, MSP\t\n" // Move MSP into R0. "mrsne r0, PSP\t\n" // Move PSP into R0. "b nrf_svc_handler_c\t\n" // Call C-implementation of handler. Exception stack frame in R0 ".align\t\n" // Protect with alignment ); } #elif defined ( __ICCARM__ ) void SVC_Handler(void) { __ASM volatile ( "tst lr, #4\t\n" // Test bit in link register responsible for stack indication. "ite eq\t\n" // Test bit 2 of EXT_RETURN to see if MSP or PSP is used "mrseq r0, MSP\t\n" // Move MSP into R0. "mrsne r0, PSP\t\n" // Move PSP into R0. "b nrf_svc_handler_c\t\n" : // Call C-implementation of handler. Exception stack frame in R0 ); } #else #error Compiler not supported. #endif