xref: /openbmc/linux/arch/powerpc/include/asm/probes.h (revision 3213486f)
1 #ifndef _ASM_POWERPC_PROBES_H
2 #define _ASM_POWERPC_PROBES_H
3 #ifdef __KERNEL__
4 /*
5  * Definitions common to probes files
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20  *
21  * Copyright IBM Corporation, 2012
22  */
23 #include <linux/types.h>
24 
25 typedef u32 ppc_opcode_t;
26 #define BREAKPOINT_INSTRUCTION	0x7fe00008	/* trap */
27 
28 /* Trap definitions per ISA */
29 #define IS_TW(instr)		(((instr) & 0xfc0007fe) == 0x7c000008)
30 #define IS_TD(instr)		(((instr) & 0xfc0007fe) == 0x7c000088)
31 #define IS_TDI(instr)		(((instr) & 0xfc000000) == 0x08000000)
32 #define IS_TWI(instr)		(((instr) & 0xfc000000) == 0x0c000000)
33 
34 #ifdef CONFIG_PPC64
35 #define is_trap(instr)		(IS_TW(instr) || IS_TD(instr) || \
36 				IS_TWI(instr) || IS_TDI(instr))
37 #else
38 #define is_trap(instr)		(IS_TW(instr) || IS_TWI(instr))
39 #endif /* CONFIG_PPC64 */
40 
41 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
42 #define MSR_SINGLESTEP	(MSR_DE)
43 #else
44 #define MSR_SINGLESTEP	(MSR_SE)
45 #endif
46 
47 /* Enable single stepping for the current task */
48 static inline void enable_single_step(struct pt_regs *regs)
49 {
50 	regs->msr |= MSR_SINGLESTEP;
51 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
52 	/*
53 	 * We turn off Critical Input Exception(CE) to ensure that the single
54 	 * step will be for the instruction we have the probe on; if we don't,
55 	 * it is possible we'd get the single step reported for CE.
56 	 */
57 	regs->msr &= ~MSR_CE;
58 	mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) | DBCR0_IC | DBCR0_IDM);
59 #ifdef CONFIG_PPC_47x
60 	isync();
61 #endif
62 #endif
63 }
64 
65 
66 #endif /* __KERNEL__ */
67 #endif	/* _ASM_POWERPC_PROBES_H */
68