BUG=b:109749762 TEST=Verified GDB still functions by hitting Ctrl+G on the developer screen and stepping through some code. Change-Id: I723a8a95f681c500d9d8e35e49fd1d893cb1f133 Signed-off-by: Raul E Rangel <rrangel@chromium.org> Reviewed-on: https://review.coreboot.org/28240 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Martin Roth <martinroth@google.com>
		
			
				
	
	
		
			90 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			90 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright 2014 Google Inc.
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|  *
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|  * This program is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU General Public License as
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|  * published by the Free Software Foundation; either version 2 of
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|  * the License, or (at your option) any later version.
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|  *
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|  * This program is distributed in the hope that it will be useful,
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|  * but without any warranty; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|  * GNU General Public License for more details.
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|  */
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| 
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| #include <exception.h>
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| #include <gdb.h>
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| #include <libpayload.h>
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| 
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| static const u8 type_to_signal[] = {
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| 	[EXC_DE]  = GDB_SIGFPE,
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| 	[EXC_DB]  = GDB_SIGTRAP,
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| 	[EXC_NMI] = GDB_SIGKILL,
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| 	[EXC_BP]  = GDB_SIGTRAP,
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| 	[EXC_OF]  = GDB_SIGFPE,
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| 	[EXC_BR]  = GDB_SIGSEGV,
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| 	[EXC_UD]  = GDB_SIGILL,
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| 	[EXC_NM]  = GDB_SIGEMT,
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| 	[EXC_DF]  = GDB_SIGKILL,
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| 	[EXC_TS]  = GDB_SIGSEGV,
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| 	[EXC_NP]  = GDB_SIGSEGV,
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| 	[EXC_SS]  = GDB_SIGBUS,
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| 	[EXC_GP]  = GDB_SIGSEGV,
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| 	[EXC_PF]  = GDB_SIGSEGV,
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| 	[EXC_MF]  = GDB_SIGEMT,
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| 	[EXC_AC]  = GDB_SIGBUS,
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| 	[EXC_MC]  = GDB_SIGKILL,
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| 	[EXC_XF]  = GDB_SIGFPE,
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| 	[EXC_SX]  = GDB_SIGFPE,
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| };
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| 
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| static void gdb_exception_hook(u8 vector)
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| {
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| 	gdb_command_loop(type_to_signal[vector]);
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| }
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| 
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| void gdb_arch_init(void)
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| {
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| 	for (int vector = 0; vector < ARRAY_SIZE(type_to_signal); ++vector) {
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| 		if (type_to_signal[vector])
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| 			set_interrupt_handler(vector, &gdb_exception_hook);
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| 	}
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| }
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| 
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| void gdb_arch_enter(void)
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| {
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| 	u32 *esp;
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| 
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| 	asm volatile ("mov %%esp, %0" : "=r"(esp) );
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| 
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| 	/* Avoid reentrant exceptions, just call the hook if in one already. */
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| 	if (esp >= exception_stack && esp <= exception_stack_end)
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| 		gdb_exception_hook(EXC_BP);
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| 	else
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| 		asm volatile ("int3");
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| }
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| 
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| int gdb_arch_set_single_step(int on)
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| {
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| 	const u32 tf_bit = 1 << 8;
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| 
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| 	if (on)
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| 		exception_state->regs.eflags |= tf_bit;
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| 	else
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| 		exception_state->regs.eflags &= ~tf_bit;
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| 
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| 	return 0;
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| }
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| 
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| void gdb_arch_encode_regs(struct gdb_message *message)
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| {
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| 	gdb_message_encode_bytes(message, &exception_state->regs,
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| 				 sizeof(exception_state->regs));
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| }
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| 
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| void gdb_arch_decode_regs(int offset, struct gdb_message *message)
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| {
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| 	gdb_message_decode_bytes(message, offset, &exception_state->regs,
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| 				 sizeof(exception_state->regs));
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| }
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