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Diffstat (limited to 'sos-code-article6.5/hwcore/exception.c')
| -rw-r--r-- | sos-code-article6.5/hwcore/exception.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/sos-code-article6.5/hwcore/exception.c b/sos-code-article6.5/hwcore/exception.c new file mode 100644 index 0000000..ffad632 --- /dev/null +++ b/sos-code-article6.5/hwcore/exception.c @@ -0,0 +1,167 @@ +/* Copyright (C) 2004 David Decotigny + + 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 2 + 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, write to the Free Software + Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, + USA. +*/ +#include "idt.h" +#include "irq.h" + +#include <sos/assert.h> +#include "exception.h" + +/* array of exception wrappers, defined in exception_wrappers.S */ +extern sos_vaddr_t sos_exception_wrapper_array[SOS_EXCEPT_NUM]; + +/* arrays of exception handlers, shared with exception_wrappers.S */ +sos_exception_handler_t sos_exception_handler_array[SOS_EXCEPT_NUM] = + { NULL, }; + +/* List of exception names for the x86 architecture */ +static const char * sos_x86_exnames[] = { + [SOS_EXCEPT_DIVIDE_ERROR] = "Division by zero", + [SOS_EXCEPT_DEBUG] = "Debug", + [SOS_EXCEPT_NMI_INTERRUPT] = "Non Maskable Interrupt", + [SOS_EXCEPT_BREAKPOINT] = "Breakpoint", + [SOS_EXCEPT_OVERFLOW] = "Overflow", + [SOS_EXCEPT_BOUND_RANGE_EXCEDEED] = "Bound Range Exceeded", + [SOS_EXCEPT_INVALID_OPCODE] = "Invalid Opcode", + [SOS_EXCEPT_DEVICE_NOT_AVAILABLE] = "Device Unavailable", + [SOS_EXCEPT_DOUBLE_FAULT] = "Double Fault", + [SOS_EXCEPT_COPROCESSOR_SEGMENT_OVERRUN] = "Coprocessor Segment Overrun", + [SOS_EXCEPT_INVALID_TSS] = "Invalid TSS", + [SOS_EXCEPT_SEGMENT_NOT_PRESENT] = "Segment Not Present", + [SOS_EXCEPT_STACK_SEGMENT_FAULT] = "Stack Segfault", + [SOS_EXCEPT_GENERAL_PROTECTION] = "General Protection", + [SOS_EXCEPT_PAGE_FAULT] = "Page Fault", + [SOS_EXCEPT_INTEL_RESERVED_1] = "INTEL1", + [SOS_EXCEPT_FLOATING_POINT_ERROR] = "FP Error", + [SOS_EXCEPT_ALIGNEMENT_CHECK] = "Alignment Check", + [SOS_EXCEPT_MACHINE_CHECK] = "Machine Check", + [SOS_EXCEPT_INTEL_RESERVED_2] = "INTEL2", + [SOS_EXCEPT_INTEL_RESERVED_3] = "INTEL3", + [SOS_EXCEPT_INTEL_RESERVED_4] = "INTEL4", + [SOS_EXCEPT_INTEL_RESERVED_5] = "INTEL5", + [SOS_EXCEPT_INTEL_RESERVED_6] = "INTEL6", + [SOS_EXCEPT_INTEL_RESERVED_7] = "INTEL7", + [SOS_EXCEPT_INTEL_RESERVED_8] = "INTEL8", + [SOS_EXCEPT_INTEL_RESERVED_9] = "INTEL9", + [SOS_EXCEPT_INTEL_RESERVED_10] = "INTEL10", + [SOS_EXCEPT_INTEL_RESERVED_11] = "INTEL11", + [SOS_EXCEPT_INTEL_RESERVED_12] = "INTEL12", + [SOS_EXCEPT_INTEL_RESERVED_13] = "INTEL13", + [SOS_EXCEPT_INTEL_RESERVED_14] = "INTEL14" +}; + + +/* Catch-all exception handler */ +static void sos_generic_ex(int exid, const struct sos_cpu_state *ctxt) +{ + const char *exname = sos_exception_get_name(exid); + + sos_display_fatal_error("Exception %s in Kernel at instruction 0x%x (info=%x)!\n", + exname, + sos_cpu_context_get_PC(ctxt), + (unsigned)sos_cpu_context_get_EX_info(ctxt)); +} + + +sos_ret_t sos_exception_subsystem_setup(void) +{ + sos_ret_t retval; + int exid; + + /* Setup the generic exception handler by default for everybody + except for the double fault exception */ + for (exid = 0 ; exid < SOS_EXCEPT_NUM ; exid ++) + { + /* Skip double fault (see below) */ + if (exid == SOS_EXCEPT_DOUBLE_FAULT) + continue; + + retval = sos_exception_set_routine(exid, sos_generic_ex); + if (SOS_OK != retval) + return retval; + } + + + /* We inidicate that the double fault exception handler is defined, + and give its address. this handler is a do-nothing handler (see + exception_wrappers.S), and it can NOT be overriden by the + functions below */ + return sos_idt_set_handler(SOS_EXCEPT_BASE + SOS_EXCEPT_DOUBLE_FAULT, + (sos_vaddr_t) sos_exception_wrapper_array[SOS_EXCEPT_DOUBLE_FAULT], + 0 /* CPL0 routine */); +} + + +sos_ret_t sos_exception_set_routine(int exception_number, + sos_exception_handler_t routine) +{ + sos_ret_t retval; + sos_ui32_t flags; + + if ((exception_number < 0) || (exception_number >= SOS_EXCEPT_NUM)) + return -SOS_EINVAL; + + /* Double fault not supported */ + if (exception_number == SOS_EXCEPT_DOUBLE_FAULT) + return -SOS_ENOSUP; + + sos_disable_IRQs(flags); + + retval = SOS_OK; + + /* Set the exception routine to be called by the exception wrapper */ + sos_exception_handler_array[exception_number] = routine; + + /* If the exception is to be enabled, update the IDT with the exception + wrapper */ + if (routine != NULL) + retval + = sos_idt_set_handler(SOS_EXCEPT_BASE + exception_number, + (sos_vaddr_t) sos_exception_wrapper_array[exception_number], + 0 /* CPL0 routine */); + else /* Disable the IDT entry */ + retval + = sos_idt_set_handler(SOS_EXCEPT_BASE + exception_number, + (sos_vaddr_t)NULL /* No routine => disable IDTE */, + 0 /* don't care */); + + sos_restore_IRQs(flags); + return retval; +} + + +sos_exception_handler_t sos_exception_get_routine(int exception_number) +{ + if ((exception_number < 0) || (exception_number >= SOS_EXCEPT_NUM)) + return NULL; + + /* Double fault not supported */ + if (exception_number == SOS_EXCEPT_DOUBLE_FAULT) + return NULL; + + /* Expected to be atomic */ + return sos_exception_handler_array[exception_number]; +} + + +const char * sos_exception_get_name(int exception_number) +{ + if ((exception_number < 0) || (exception_number >= SOS_EXCEPT_NUM)) + return NULL; + + return sos_x86_exnames[exception_number]; +} |