| /* |
| * Copyright (c) 2015 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 dynamic exception handler wrapper |
| */ |
| |
| #define _ASMLANGUAGE |
| |
| #include <toolchain.h> |
| #include <arch/cpu.h> |
| |
| _ASM_FILE_PROLOGUE |
| |
| GDATA(_sw_exc_table) |
| GTEXT(_exc_wrapper) |
| |
| SECTION_FUNC(TEXT, _exc_wrapper) |
| |
| _GDB_STUB_EXC_ENTRY |
| |
| ldr ip, =_SCS_ICSR |
| ldr ip, [ip] |
| ands.w ip, #_SCS_ICSR_RETTOBASE |
| |
| itte eq /* is the RETTOBASE bit zero ? */ |
| mrseq r0, MSP /* if so, we're not returning to thread mode, thus this |
| * is a nested exception: the stack frame is on the MSP */ |
| addeq.w r0, #4 /* ESF returned here is off by 4 because of the push {r2} |
| * in_GDB_STUB_EXC_ENTRY */ |
| mrsne r0, PSP /* if not, we are returning to thread mode, thus this is |
| * not a nested exception: the stack frame is on the PSP */ |
| |
| /* r0 now contains the pointer to the full ESF */ |
| |
| push {lr} /* lr is now the first item on the stack */ |
| |
| ldr r1, =_sw_exc_table |
| |
| mrs r2, IPSR /* get exception number */ |
| |
| /* find and call handler: table is 4-bytes wide, shift index by 2 */ |
| ldr r1, [r1, r2, LSL #2] |
| blx r1 |
| |
| pop {lr} |
| |
| /* exception return is done in _ExcExit(), including _GDB_STUB_EXC_EXIT */ |
| b _ExcExit |
| |
| .end |
