 7acf71d1a2
			
		
	
	
	7acf71d1a2
	
	
	
		
			
			Some of the KGDB macros used for generating the BRK instructions had the wrong spelling for DBG and KGDB abbreviations. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
		
			
				
	
	
		
			336 lines
		
	
	
	
		
			8.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			336 lines
		
	
	
	
		
			8.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * AArch64 KGDB support
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|  *
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|  * Based on arch/arm/kernel/kgdb.c
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|  *
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|  * Copyright (C) 2013 Cavium Inc.
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|  * Author: Vijaya Kumar K <vijaya.kumar@caviumnetworks.com>
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|  *
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|  * This program is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License version 2 as
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|  * published by the Free Software Foundation.
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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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|  * You should have received a copy of the GNU General Public License
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|  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
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|  */
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| 
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| #include <linux/irq.h>
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| #include <linux/kdebug.h>
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| #include <linux/kgdb.h>
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| #include <asm/traps.h>
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| 
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| struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = {
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| 	{ "x0", 8, offsetof(struct pt_regs, regs[0])},
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| 	{ "x1", 8, offsetof(struct pt_regs, regs[1])},
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| 	{ "x2", 8, offsetof(struct pt_regs, regs[2])},
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| 	{ "x3", 8, offsetof(struct pt_regs, regs[3])},
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| 	{ "x4", 8, offsetof(struct pt_regs, regs[4])},
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| 	{ "x5", 8, offsetof(struct pt_regs, regs[5])},
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| 	{ "x6", 8, offsetof(struct pt_regs, regs[6])},
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| 	{ "x7", 8, offsetof(struct pt_regs, regs[7])},
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| 	{ "x8", 8, offsetof(struct pt_regs, regs[8])},
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| 	{ "x9", 8, offsetof(struct pt_regs, regs[9])},
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| 	{ "x10", 8, offsetof(struct pt_regs, regs[10])},
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| 	{ "x11", 8, offsetof(struct pt_regs, regs[11])},
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| 	{ "x12", 8, offsetof(struct pt_regs, regs[12])},
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| 	{ "x13", 8, offsetof(struct pt_regs, regs[13])},
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| 	{ "x14", 8, offsetof(struct pt_regs, regs[14])},
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| 	{ "x15", 8, offsetof(struct pt_regs, regs[15])},
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| 	{ "x16", 8, offsetof(struct pt_regs, regs[16])},
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| 	{ "x17", 8, offsetof(struct pt_regs, regs[17])},
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| 	{ "x18", 8, offsetof(struct pt_regs, regs[18])},
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| 	{ "x19", 8, offsetof(struct pt_regs, regs[19])},
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| 	{ "x20", 8, offsetof(struct pt_regs, regs[20])},
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| 	{ "x21", 8, offsetof(struct pt_regs, regs[21])},
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| 	{ "x22", 8, offsetof(struct pt_regs, regs[22])},
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| 	{ "x23", 8, offsetof(struct pt_regs, regs[23])},
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| 	{ "x24", 8, offsetof(struct pt_regs, regs[24])},
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| 	{ "x25", 8, offsetof(struct pt_regs, regs[25])},
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| 	{ "x26", 8, offsetof(struct pt_regs, regs[26])},
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| 	{ "x27", 8, offsetof(struct pt_regs, regs[27])},
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| 	{ "x28", 8, offsetof(struct pt_regs, regs[28])},
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| 	{ "x29", 8, offsetof(struct pt_regs, regs[29])},
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| 	{ "x30", 8, offsetof(struct pt_regs, regs[30])},
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| 	{ "sp", 8, offsetof(struct pt_regs, sp)},
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| 	{ "pc", 8, offsetof(struct pt_regs, pc)},
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| 	{ "pstate", 8, offsetof(struct pt_regs, pstate)},
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| 	{ "v0", 16, -1 },
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| 	{ "v1", 16, -1 },
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| 	{ "v2", 16, -1 },
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| 	{ "v3", 16, -1 },
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| 	{ "v4", 16, -1 },
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| 	{ "v5", 16, -1 },
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| 	{ "v6", 16, -1 },
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| 	{ "v7", 16, -1 },
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| 	{ "v8", 16, -1 },
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| 	{ "v9", 16, -1 },
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| 	{ "v10", 16, -1 },
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| 	{ "v11", 16, -1 },
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| 	{ "v12", 16, -1 },
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| 	{ "v13", 16, -1 },
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| 	{ "v14", 16, -1 },
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| 	{ "v15", 16, -1 },
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| 	{ "v16", 16, -1 },
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| 	{ "v17", 16, -1 },
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| 	{ "v18", 16, -1 },
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| 	{ "v19", 16, -1 },
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| 	{ "v20", 16, -1 },
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| 	{ "v21", 16, -1 },
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| 	{ "v22", 16, -1 },
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| 	{ "v23", 16, -1 },
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| 	{ "v24", 16, -1 },
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| 	{ "v25", 16, -1 },
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| 	{ "v26", 16, -1 },
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| 	{ "v27", 16, -1 },
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| 	{ "v28", 16, -1 },
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| 	{ "v29", 16, -1 },
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| 	{ "v30", 16, -1 },
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| 	{ "v31", 16, -1 },
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| 	{ "fpsr", 4, -1 },
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| 	{ "fpcr", 4, -1 },
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| };
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| 
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| char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs)
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| {
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| 	if (regno >= DBG_MAX_REG_NUM || regno < 0)
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| 		return NULL;
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| 
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| 	if (dbg_reg_def[regno].offset != -1)
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| 		memcpy(mem, (void *)regs + dbg_reg_def[regno].offset,
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| 		       dbg_reg_def[regno].size);
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| 	else
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| 		memset(mem, 0, dbg_reg_def[regno].size);
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| 	return dbg_reg_def[regno].name;
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| }
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| 
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| int dbg_set_reg(int regno, void *mem, struct pt_regs *regs)
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| {
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| 	if (regno >= DBG_MAX_REG_NUM || regno < 0)
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| 		return -EINVAL;
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| 
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| 	if (dbg_reg_def[regno].offset != -1)
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| 		memcpy((void *)regs + dbg_reg_def[regno].offset, mem,
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| 		       dbg_reg_def[regno].size);
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| 	return 0;
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| }
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| 
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| void
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| sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *task)
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| {
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| 	struct pt_regs *thread_regs;
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| 
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| 	/* Initialize to zero */
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| 	memset((char *)gdb_regs, 0, NUMREGBYTES);
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| 	thread_regs = task_pt_regs(task);
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| 	memcpy((void *)gdb_regs, (void *)thread_regs->regs, GP_REG_BYTES);
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| }
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| 
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| void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc)
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| {
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| 	regs->pc = pc;
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| }
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| 
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| static int compiled_break;
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| 
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| static void kgdb_arch_update_addr(struct pt_regs *regs,
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| 				char *remcom_in_buffer)
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| {
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| 	unsigned long addr;
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| 	char *ptr;
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| 
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| 	ptr = &remcom_in_buffer[1];
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| 	if (kgdb_hex2long(&ptr, &addr))
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| 		kgdb_arch_set_pc(regs, addr);
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| 	else if (compiled_break == 1)
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| 		kgdb_arch_set_pc(regs, regs->pc + 4);
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| 
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| 	compiled_break = 0;
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| }
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| 
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| int kgdb_arch_handle_exception(int exception_vector, int signo,
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| 			       int err_code, char *remcom_in_buffer,
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| 			       char *remcom_out_buffer,
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| 			       struct pt_regs *linux_regs)
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| {
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| 	int err;
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| 
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| 	switch (remcom_in_buffer[0]) {
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| 	case 'D':
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| 	case 'k':
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| 		/*
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| 		 * Packet D (Detach), k (kill). No special handling
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| 		 * is required here. Handle same as c packet.
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| 		 */
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| 	case 'c':
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| 		/*
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| 		 * Packet c (Continue) to continue executing.
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| 		 * Set pc to required address.
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| 		 * Try to read optional parameter and set pc.
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| 		 * If this was a compiled breakpoint, we need to move
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| 		 * to the next instruction else we will just breakpoint
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| 		 * over and over again.
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| 		 */
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| 		kgdb_arch_update_addr(linux_regs, remcom_in_buffer);
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| 		atomic_set(&kgdb_cpu_doing_single_step, -1);
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| 		kgdb_single_step =  0;
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| 
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| 		/*
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| 		 * Received continue command, disable single step
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| 		 */
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| 		if (kernel_active_single_step())
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| 			kernel_disable_single_step();
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| 
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| 		err = 0;
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| 		break;
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| 	case 's':
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| 		/*
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| 		 * Update step address value with address passed
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| 		 * with step packet.
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| 		 * On debug exception return PC is copied to ELR
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| 		 * So just update PC.
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| 		 * If no step address is passed, resume from the address
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| 		 * pointed by PC. Do not update PC
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| 		 */
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| 		kgdb_arch_update_addr(linux_regs, remcom_in_buffer);
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| 		atomic_set(&kgdb_cpu_doing_single_step, raw_smp_processor_id());
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| 		kgdb_single_step =  1;
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| 
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| 		/*
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| 		 * Enable single step handling
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| 		 */
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| 		if (!kernel_active_single_step())
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| 			kernel_enable_single_step(linux_regs);
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| 		err = 0;
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| 		break;
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| 	default:
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| 		err = -1;
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| 	}
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| 	return err;
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| }
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| 
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| static int kgdb_brk_fn(struct pt_regs *regs, unsigned int esr)
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| {
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| 	kgdb_handle_exception(1, SIGTRAP, 0, regs);
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| 	return 0;
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| }
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| 
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| static int kgdb_compiled_brk_fn(struct pt_regs *regs, unsigned int esr)
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| {
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| 	compiled_break = 1;
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| 	kgdb_handle_exception(1, SIGTRAP, 0, regs);
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| 
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| 	return 0;
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| }
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| 
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| static int kgdb_step_brk_fn(struct pt_regs *regs, unsigned int esr)
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| {
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| 	kgdb_handle_exception(1, SIGTRAP, 0, regs);
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| 	return 0;
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| }
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| 
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| static struct break_hook kgdb_brkpt_hook = {
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| 	.esr_mask	= 0xffffffff,
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| 	.esr_val	= DBG_ESR_VAL_BRK(KGDB_DYN_DBG_BRK_IMM),
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| 	.fn		= kgdb_brk_fn
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| };
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| 
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| static struct break_hook kgdb_compiled_brkpt_hook = {
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| 	.esr_mask	= 0xffffffff,
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| 	.esr_val	= DBG_ESR_VAL_BRK(KGDB_COMPILED_DBG_BRK_IMM),
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| 	.fn		= kgdb_compiled_brk_fn
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| };
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| 
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| static struct step_hook kgdb_step_hook = {
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| 	.fn		= kgdb_step_brk_fn
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| };
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| 
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| static void kgdb_call_nmi_hook(void *ignored)
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| {
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| 	kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs());
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| }
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| 
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| void kgdb_roundup_cpus(unsigned long flags)
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| {
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| 	local_irq_enable();
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| 	smp_call_function(kgdb_call_nmi_hook, NULL, 0);
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| 	local_irq_disable();
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| }
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| 
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| static int __kgdb_notify(struct die_args *args, unsigned long cmd)
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| {
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| 	struct pt_regs *regs = args->regs;
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| 
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| 	if (kgdb_handle_exception(1, args->signr, cmd, regs))
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| 		return NOTIFY_DONE;
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| 	return NOTIFY_STOP;
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| }
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| 
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| static int
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| kgdb_notify(struct notifier_block *self, unsigned long cmd, void *ptr)
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| {
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| 	unsigned long flags;
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| 	int ret;
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| 
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| 	local_irq_save(flags);
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| 	ret = __kgdb_notify(ptr, cmd);
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| 	local_irq_restore(flags);
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| 
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| 	return ret;
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| }
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| 
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| static struct notifier_block kgdb_notifier = {
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| 	.notifier_call	= kgdb_notify,
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| 	/*
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| 	 * Want to be lowest priority
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| 	 */
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| 	.priority	= -INT_MAX,
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| };
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| 
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| /*
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|  * kgdb_arch_init - Perform any architecture specific initalization.
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|  * This function will handle the initalization of any architecture
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|  * specific callbacks.
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|  */
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| int kgdb_arch_init(void)
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| {
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| 	int ret = register_die_notifier(&kgdb_notifier);
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| 
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| 	if (ret != 0)
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| 		return ret;
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| 
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| 	register_break_hook(&kgdb_brkpt_hook);
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| 	register_break_hook(&kgdb_compiled_brkpt_hook);
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| 	register_step_hook(&kgdb_step_hook);
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| 	return 0;
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| }
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| 
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| /*
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|  * kgdb_arch_exit - Perform any architecture specific uninitalization.
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|  * This function will handle the uninitalization of any architecture
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|  * specific callbacks, for dynamic registration and unregistration.
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|  */
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| void kgdb_arch_exit(void)
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| {
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| 	unregister_break_hook(&kgdb_brkpt_hook);
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| 	unregister_break_hook(&kgdb_compiled_brkpt_hook);
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| 	unregister_step_hook(&kgdb_step_hook);
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| 	unregister_die_notifier(&kgdb_notifier);
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| }
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| 
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| /*
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|  * ARM instructions are always in LE.
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|  * Break instruction is encoded in LE format
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|  */
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| struct kgdb_arch arch_kgdb_ops = {
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| 	.gdb_bpt_instr = {
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| 		KGDB_DYN_BRK_INS_BYTE0,
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| 		KGDB_DYN_BRK_INS_BYTE1,
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| 		KGDB_DYN_BRK_INS_BYTE2,
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| 		KGDB_DYN_BRK_INS_BYTE3,
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| 	}
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| };
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