diff options
Diffstat (limited to 'arch/x86/include/uapi/asm/debugreg.h')
| -rw-r--r-- | arch/x86/include/uapi/asm/debugreg.h | 80 | 
1 files changed, 80 insertions, 0 deletions
diff --git a/arch/x86/include/uapi/asm/debugreg.h b/arch/x86/include/uapi/asm/debugreg.h new file mode 100644 index 00000000000..3c0874dd986 --- /dev/null +++ b/arch/x86/include/uapi/asm/debugreg.h @@ -0,0 +1,80 @@ +#ifndef _UAPI_ASM_X86_DEBUGREG_H +#define _UAPI_ASM_X86_DEBUGREG_H + + +/* Indicate the register numbers for a number of the specific +   debug registers.  Registers 0-3 contain the addresses we wish to trap on */ +#define DR_FIRSTADDR 0        /* u_debugreg[DR_FIRSTADDR] */ +#define DR_LASTADDR 3         /* u_debugreg[DR_LASTADDR]  */ + +#define DR_STATUS 6           /* u_debugreg[DR_STATUS]     */ +#define DR_CONTROL 7          /* u_debugreg[DR_CONTROL] */ + +/* Define a few things for the status register.  We can use this to determine +   which debugging register was responsible for the trap.  The other bits +   are either reserved or not of interest to us. */ + +/* Define reserved bits in DR6 which are always set to 1 */ +#define DR6_RESERVED	(0xFFFF0FF0) + +#define DR_TRAP0	(0x1)		/* db0 */ +#define DR_TRAP1	(0x2)		/* db1 */ +#define DR_TRAP2	(0x4)		/* db2 */ +#define DR_TRAP3	(0x8)		/* db3 */ +#define DR_TRAP_BITS	(DR_TRAP0|DR_TRAP1|DR_TRAP2|DR_TRAP3) + +#define DR_STEP		(0x4000)	/* single-step */ +#define DR_SWITCH	(0x8000)	/* task switch */ + +/* Now define a bunch of things for manipulating the control register. +   The top two bytes of the control register consist of 4 fields of 4 +   bits - each field corresponds to one of the four debug registers, +   and indicates what types of access we trap on, and how large the data +   field is that we are looking at */ + +#define DR_CONTROL_SHIFT 16 /* Skip this many bits in ctl register */ +#define DR_CONTROL_SIZE 4   /* 4 control bits per register */ + +#define DR_RW_EXECUTE (0x0)   /* Settings for the access types to trap on */ +#define DR_RW_WRITE (0x1) +#define DR_RW_READ (0x3) + +#define DR_LEN_1 (0x0) /* Settings for data length to trap on */ +#define DR_LEN_2 (0x4) +#define DR_LEN_4 (0xC) +#define DR_LEN_8 (0x8) + +/* The low byte to the control register determine which registers are +   enabled.  There are 4 fields of two bits.  One bit is "local", meaning +   that the processor will reset the bit after a task switch and the other +   is global meaning that we have to explicitly reset the bit.  With linux, +   you can use either one, since we explicitly zero the register when we enter +   kernel mode. */ + +#define DR_LOCAL_ENABLE_SHIFT 0    /* Extra shift to the local enable bit */ +#define DR_GLOBAL_ENABLE_SHIFT 1   /* Extra shift to the global enable bit */ +#define DR_LOCAL_ENABLE (0x1)      /* Local enable for reg 0 */ +#define DR_GLOBAL_ENABLE (0x2)     /* Global enable for reg 0 */ +#define DR_ENABLE_SIZE 2           /* 2 enable bits per register */ + +#define DR_LOCAL_ENABLE_MASK (0x55)  /* Set  local bits for all 4 regs */ +#define DR_GLOBAL_ENABLE_MASK (0xAA) /* Set global bits for all 4 regs */ + +/* The second byte to the control register has a few special things. +   We can slow the instruction pipeline for instructions coming via the +   gdt or the ldt if we want to.  I am not sure why this is an advantage */ + +#ifdef __i386__ +#define DR_CONTROL_RESERVED (0xFC00) /* Reserved by Intel */ +#else +#define DR_CONTROL_RESERVED (0xFFFFFFFF0000FC00UL) /* Reserved */ +#endif + +#define DR_LOCAL_SLOWDOWN (0x100)   /* Local slow the pipeline */ +#define DR_GLOBAL_SLOWDOWN (0x200)  /* Global slow the pipeline */ + +/* + * HW breakpoint additions + */ + +#endif /* _UAPI_ASM_X86_DEBUGREG_H */  | 
