[linux-2.6-block.git] / arch / alpha / oprofile / op_model_ev67.c

/**
 * @file arch/alpha/oprofile/op_model_ev67.c
 *
 * @remark Copyright 2002 OProfile authors
 * @remark Read the file COPYING
 *
 * @author Richard Henderson <rth@twiddle.net>
 * @author Falk Hueffner <falk@debian.org>
 */

#include <linux/oprofile.h>
#include <linux/init.h>
#include <linux/smp.h>
#include <asm/ptrace.h>

#include "op_impl.h"


/* Compute all of the registers in preparation for enabling profiling.  */

static void
ev67_reg_setup(struct op_register_config *reg,
	       struct op_counter_config *ctr,
	       struct op_system_config *sys)
{
	unsigned long ctl, reset, need_reset, i;

	/* Select desired events.  */
	ctl = 1UL << 4;		/* Enable ProfileMe mode. */

	/* The event numbers are chosen so we can use them directly if
	   PCTR1 is enabled.  */
	if (ctr[1].enabled) {
		ctl |= (ctr[1].event & 3) << 2;
	} else {
		if (ctr[0].event == 0) /* cycles */
			ctl |= 1UL << 2;
	}
	reg->mux_select = ctl;

	/* Select logging options.  */
	/* ??? Need to come up with some mechanism to trace only
	   selected processes.  EV67 does not have a mechanism to
	   select kernel or user mode only.  For now, enable always.  */
	reg->proc_mode = 0;

	/* EV67 cannot change the width of the counters as with the
	   other implementations.  But fortunately, we can write to
	   the counters and set the value such that it will overflow
	   at the right time.  */
	reset = need_reset = 0;
	for (i = 0; i < 2; ++i) {
		unsigned long count = ctr[i].count;
		if (!ctr[i].enabled)
			continue;

		if (count > 0x100000)
			count = 0x100000;
		ctr[i].count = count;
		reset |= (0x100000 - count) << (i ? 6 : 28);
		if (count != 0x100000)
			need_reset |= 1 << i;
	}
	reg->reset_values = reset;
	reg->need_reset = need_reset;
}

/* Program all of the registers in preparation for enabling profiling.  */

static void
ev67_cpu_setup (void *x)
{
	struct op_register_config *reg = x;

	wrperfmon(2, reg->mux_select);
	wrperfmon(3, reg->proc_mode);
	wrperfmon(6, reg->reset_values | 3);
}

/* CTR is a counter for which the user has requested an interrupt count
   in between one of the widths selectable in hardware.  Reset the count
   for CTR to the value stored in REG->RESET_VALUES.  */

static void
ev67_reset_ctr(struct op_register_config *reg, unsigned long ctr)
{
	wrperfmon(6, reg->reset_values | (1 << ctr));
}

/* ProfileMe conditions which will show up as counters. We can also
   detect the following, but it seems unlikely that anybody is
   interested in counting them:
    * Reset
    * MT_FPCR (write to floating point control register)
    * Arithmetic trap
    * Dstream Fault
    * Machine Check (ECC fault, etc.)
    * OPCDEC (illegal opcode)
    * Floating point disabled
    * Differentiate between DTB single/double misses and 3 or 4 level
      page tables
    * Istream access violation
    * Interrupt
    * Icache Parity Error.
    * Instruction killed (nop, trapb)

   Unfortunately, there seems to be no way to detect Dcache and Bcache
   misses; the latter could be approximated by making the counter
   count Bcache misses, but that is not precise.

   We model this as 20 counters:
    * PCTR0
    * PCTR1
    * 9 ProfileMe events, induced by PCTR0
    * 9 ProfileMe events, induced by PCTR1
*/

enum profileme_counters {
	PM_STALLED,		/* Stalled for at least one cycle
				   between the fetch and map stages  */
	PM_TAKEN,		/* Conditional branch taken */
	PM_MISPREDICT,		/* Branch caused mispredict trap */
	PM_ITB_MISS,		/* ITB miss */
	PM_DTB_MISS,		/* DTB miss */
	PM_REPLAY,		/* Replay trap */
	PM_LOAD_STORE,		/* Load-store order trap */
	PM_ICACHE_MISS,		/* Icache miss */
	PM_UNALIGNED,		/* Unaligned Load/Store */
	PM_NUM_COUNTERS
};

static inline void
op_add_pm(unsigned long pc, int kern, unsigned long counter,
	  struct op_counter_config *ctr, unsigned long event)
{
	unsigned long fake_counter = 2 + event;
	if (counter == 1)
		fake_counter += PM_NUM_COUNTERS;
	if (ctr[fake_counter].enabled)
		oprofile_add_pc(pc, kern, fake_counter);
}

static void
ev67_handle_interrupt(unsigned long which, struct pt_regs *regs,
		      struct op_counter_config *ctr)
{
	unsigned long pmpc, pctr_ctl;
	int kern = !user_mode(regs);
	int mispredict = 0;
	union {
		unsigned long v;
		struct {
			unsigned reserved:	30; /*  0-29 */
			unsigned overcount:	 3; /* 30-32 */
			unsigned icache_miss:	 1; /*    33 */
			unsigned trap_type:	 4; /* 34-37 */
			unsigned load_store:	 1; /*    38 */
			unsigned trap:		 1; /*    39 */
			unsigned mispredict:	 1; /*    40 */
		} fields;
	} i_stat;

	enum trap_types {
		TRAP_REPLAY,
		TRAP_INVALID0,
		TRAP_DTB_DOUBLE_MISS_3,
		TRAP_DTB_DOUBLE_MISS_4,
		TRAP_FP_DISABLED,
		TRAP_UNALIGNED,
		TRAP_DTB_SINGLE_MISS,
		TRAP_DSTREAM_FAULT,
		TRAP_OPCDEC,
		TRAP_INVALID1,
		TRAP_MACHINE_CHECK,
		TRAP_INVALID2,
		TRAP_ARITHMETIC,
		TRAP_INVALID3,
		TRAP_MT_FPCR,
		TRAP_RESET
	};

	pmpc = wrperfmon(9, 0);
	/* ??? Don't know how to handle physical-mode PALcode address.  */
	if (pmpc & 1)
		return;
	pmpc &= ~2;		/* clear reserved bit */

	i_stat.v = wrperfmon(8, 0);
	if (i_stat.fields.trap) {
		switch (i_stat.fields.trap_type) {
		case TRAP_INVALID1:
		case TRAP_INVALID2:
		case TRAP_INVALID3:
			/* Pipeline redirection occurred. PMPC points
			   to PALcode. Recognize ITB miss by PALcode
			   offset address, and get actual PC from
			   EXC_ADDR.  */
			oprofile_add_pc(regs->pc, kern, which);
			if ((pmpc & ((1 << 15) - 1)) ==  581)
				op_add_pm(regs->pc, kern, which,
					  ctr, PM_ITB_MISS);
			/* Most other bit and counter values will be
			   those for the first instruction in the
			   fault handler, so we're done.  */
			return;
		case TRAP_REPLAY:
			op_add_pm(pmpc, kern, which, ctr,
				  (i_stat.fields.load_store
				   ? PM_LOAD_STORE : PM_REPLAY));
			break;
		case TRAP_DTB_DOUBLE_MISS_3:
		case TRAP_DTB_DOUBLE_MISS_4:
		case TRAP_DTB_SINGLE_MISS:
			op_add_pm(pmpc, kern, which, ctr, PM_DTB_MISS);
			break;
		case TRAP_UNALIGNED:
			op_add_pm(pmpc, kern, which, ctr, PM_UNALIGNED);
			break;
		case TRAP_INVALID0:
		case TRAP_FP_DISABLED:
		case TRAP_DSTREAM_FAULT:
		case TRAP_OPCDEC:
		case TRAP_MACHINE_CHECK:
		case TRAP_ARITHMETIC:
		case TRAP_MT_FPCR:
		case TRAP_RESET:
			break;
		}

		/* ??? JSR/JMP/RET/COR or HW_JSR/HW_JMP/HW_RET/HW_COR
		   mispredicts do not set this bit but can be
		   recognized by the presence of one of these
		   instructions at the PMPC location with bit 39
		   set.  */
		if (i_stat.fields.mispredict) {
			mispredict = 1;
			op_add_pm(pmpc, kern, which, ctr, PM_MISPREDICT);
		}
	}

	oprofile_add_pc(pmpc, kern, which);

	pctr_ctl = wrperfmon(5, 0);
	if (pctr_ctl & (1UL << 27))
		op_add_pm(pmpc, kern, which, ctr, PM_STALLED);

	/* Unfortunately, TAK is undefined on mispredicted branches.
	   ??? It is also undefined for non-cbranch insns, should
	   check that.  */
	if (!mispredict && pctr_ctl & (1UL << 0))
		op_add_pm(pmpc, kern, which, ctr, PM_TAKEN);
}

struct op_axp_model op_model_ev67 = {
	.reg_setup		= ev67_reg_setup,
	.cpu_setup		= ev67_cpu_setup,
	.reset_ctr		= ev67_reset_ctr,
	.handle_interrupt	= ev67_handle_interrupt,
	.cpu_type		= "alpha/ev67",
	.num_counters		= 20,
	.can_set_proc_mode	= 0,
};
Commit	Line	Data
1da177e4 LT	1	/**
	2	* @file arch/alpha/oprofile/op_model_ev67.c
	3	*
	4	* @remark Copyright 2002 OProfile authors
	5	* @remark Read the file COPYING
	6	*
	7	* @author Richard Henderson <rth@twiddle.net>
	8	* @author Falk Hueffner <falk@debian.org>
	9	*/
	10
	11	#include <linux/oprofile.h>
	12	#include <linux/init.h>
	13	#include <linux/smp.h>
	14	#include <asm/ptrace.h>
1da177e4 LT	15
	16	#include "op_impl.h"
	17
	18
	19	/* Compute all of the registers in preparation for enabling profiling. */
	20
	21	static void
	22	ev67_reg_setup(struct op_register_config *reg,
	23	struct op_counter_config *ctr,
	24	struct op_system_config *sys)
	25	{
	26	unsigned long ctl, reset, need_reset, i;
	27
	28	/* Select desired events. */
	29	ctl = 1UL << 4; /* Enable ProfileMe mode. */
	30
	31	/* The event numbers are chosen so we can use them directly if
	32	PCTR1 is enabled. */
	33	if (ctr[1].enabled) {
	34	ctl \|= (ctr[1].event & 3) << 2;
	35	} else {
	36	if (ctr[0].event == 0) /* cycles */
	37	ctl \|= 1UL << 2;
	38	}
	39	reg->mux_select = ctl;
	40
	41	/* Select logging options. */
	42	/* ??? Need to come up with some mechanism to trace only
	43	selected processes. EV67 does not have a mechanism to
	44	select kernel or user mode only. For now, enable always. */
	45	reg->proc_mode = 0;
	46
	47	/* EV67 cannot change the width of the counters as with the
	48	other implementations. But fortunately, we can write to
	49	the counters and set the value such that it will overflow
	50	at the right time. */
	51	reset = need_reset = 0;
	52	for (i = 0; i < 2; ++i) {
	53	unsigned long count = ctr[i].count;
	54	if (!ctr[i].enabled)
	55	continue;
	56
	57	if (count > 0x100000)
	58	count = 0x100000;
	59	ctr[i].count = count;
	60	reset \|= (0x100000 - count) << (i ? 6 : 28);
	61	if (count != 0x100000)
	62	need_reset \|= 1 << i;
	63	}
	64	reg->reset_values = reset;
	65	reg->need_reset = need_reset;
	66	}
	67
	68	/* Program all of the registers in preparation for enabling profiling. */
	69
	70	static void
	71	ev67_cpu_setup (void *x)
	72	{
	73	struct op_register_config *reg = x;
	74
	75	wrperfmon(2, reg->mux_select);
	76	wrperfmon(3, reg->proc_mode);
	77	wrperfmon(6, reg->reset_values \| 3);
	78	}
79
80	/* CTR is a counter for which the user has requested an interrupt count
81	in between one of the widths selectable in hardware. Reset the count
82	for CTR to the value stored in REG->RESET_VALUES. */
83
84	static void
85	ev67_reset_ctr(struct op_register_config *reg, unsigned long ctr)
86	{
87	wrperfmon(6, reg->reset_values \| (1 << ctr));
88	}
89
90	/* ProfileMe conditions which will show up as counters. We can also
91	detect the following, but it seems unlikely that anybody is
92	interested in counting them:
93	* Reset
94	* MT_FPCR (write to floating point control register)
95	* Arithmetic trap
96	* Dstream Fault
97	* Machine Check (ECC fault, etc.)
98	* OPCDEC (illegal opcode)
99	* Floating point disabled
100	* Differentiate between DTB single/double misses and 3 or 4 level
101	page tables
102	* Istream access violation
103	* Interrupt
104	* Icache Parity Error.
105	* Instruction killed (nop, trapb)
106
107	Unfortunately, there seems to be no way to detect Dcache and Bcache
108	misses; the latter could be approximated by making the counter
109	count Bcache misses, but that is not precise.
110
111	We model this as 20 counters:
112	* PCTR0
113	* PCTR1
114	* 9 ProfileMe events, induced by PCTR0
115	* 9 ProfileMe events, induced by PCTR1
116	*/
117
118	enum profileme_counters {
119	PM_STALLED, /* Stalled for at least one cycle
120	between the fetch and map stages */
121	PM_TAKEN, /* Conditional branch taken */
122	PM_MISPREDICT, /* Branch caused mispredict trap */
123	PM_ITB_MISS, /* ITB miss */
124	PM_DTB_MISS, /* DTB miss */
125	PM_REPLAY, /* Replay trap */
126	PM_LOAD_STORE, /* Load-store order trap */
127	PM_ICACHE_MISS, /* Icache miss */
128	PM_UNALIGNED, /* Unaligned Load/Store */
129	PM_NUM_COUNTERS
130	};
131
132	static inline void
133	op_add_pm(unsigned long pc, int kern, unsigned long counter,
134	struct op_counter_config *ctr, unsigned long event)
135	{
136	unsigned long fake_counter = 2 + event;
137	if (counter == 1)
138	fake_counter += PM_NUM_COUNTERS;
139	if (ctr[fake_counter].enabled)
140	oprofile_add_pc(pc, kern, fake_counter);
141	}
142
143	static void
144	ev67_handle_interrupt(unsigned long which, struct pt_regs *regs,
145	struct op_counter_config *ctr)
146	{
147	unsigned long pmpc, pctr_ctl;
148	int kern = !user_mode(regs);
149	int mispredict = 0;
150	union {
151	unsigned long v;
152	struct {
153	unsigned reserved: 30; /* 0-29 */
154	unsigned overcount: 3; /* 30-32 */
155	unsigned icache_miss: 1; /* 33 */
156	unsigned trap_type: 4; /* 34-37 */
157	unsigned load_store: 1; /* 38 */
158	unsigned trap: 1; /* 39 */
159	unsigned mispredict: 1; /* 40 */
160	} fields;
161	} i_stat;
162
163	enum trap_types {
164	TRAP_REPLAY,
165	TRAP_INVALID0,
166	TRAP_DTB_DOUBLE_MISS_3,
167	TRAP_DTB_DOUBLE_MISS_4,
168	TRAP_FP_DISABLED,
169	TRAP_UNALIGNED,
170	TRAP_DTB_SINGLE_MISS,
171	TRAP_DSTREAM_FAULT,
172	TRAP_OPCDEC,
173	TRAP_INVALID1,
174	TRAP_MACHINE_CHECK,
175	TRAP_INVALID2,
176	TRAP_ARITHMETIC,
177	TRAP_INVALID3,
178	TRAP_MT_FPCR,
179	TRAP_RESET
180	};
181
182	pmpc = wrperfmon(9, 0);
183	/* ??? Don't know how to handle physical-mode PALcode address. */
184	if (pmpc & 1)
185	return;
186	pmpc &= ~2; /* clear reserved bit */
187
188	i_stat.v = wrperfmon(8, 0);
189	if (i_stat.fields.trap) {
190	switch (i_stat.fields.trap_type) {
191	case TRAP_INVALID1:
192	case TRAP_INVALID2:
193	case TRAP_INVALID3:
25985edc	194	/* Pipeline redirection occurred. PMPC points
1da177e4 LT	195	to PALcode. Recognize ITB miss by PALcode
	196	offset address, and get actual PC from
	197	EXC_ADDR. */
	198	oprofile_add_pc(regs->pc, kern, which);
	199	if ((pmpc & ((1 << 15) - 1)) == 581)
	200	op_add_pm(regs->pc, kern, which,
	201	ctr, PM_ITB_MISS);
	202	/* Most other bit and counter values will be
	203	those for the first instruction in the
	204	fault handler, so we're done. */
	205	return;
	206	case TRAP_REPLAY:
	207	op_add_pm(pmpc, kern, which, ctr,
	208	(i_stat.fields.load_store
	209	? PM_LOAD_STORE : PM_REPLAY));
	210	break;
	211	case TRAP_DTB_DOUBLE_MISS_3:
	212	case TRAP_DTB_DOUBLE_MISS_4:
	213	case TRAP_DTB_SINGLE_MISS:
	214	op_add_pm(pmpc, kern, which, ctr, PM_DTB_MISS);
	215	break;
	216	case TRAP_UNALIGNED:
	217	op_add_pm(pmpc, kern, which, ctr, PM_UNALIGNED);
	218	break;
	219	case TRAP_INVALID0:
	220	case TRAP_FP_DISABLED:
	221	case TRAP_DSTREAM_FAULT:
	222	case TRAP_OPCDEC:
	223	case TRAP_MACHINE_CHECK:
	224	case TRAP_ARITHMETIC:
	225	case TRAP_MT_FPCR:
	226	case TRAP_RESET:
	227	break;
	228	}
	229
	230	/* ??? JSR/JMP/RET/COR or HW_JSR/HW_JMP/HW_RET/HW_COR
	231	mispredicts do not set this bit but can be
	232	recognized by the presence of one of these
	233	instructions at the PMPC location with bit 39
	234	set. */
	235	if (i_stat.fields.mispredict) {
	236	mispredict = 1;
	237	op_add_pm(pmpc, kern, which, ctr, PM_MISPREDICT);
	238	}
	239	}
	240
	241	oprofile_add_pc(pmpc, kern, which);
	242
	243	pctr_ctl = wrperfmon(5, 0);
	244	if (pctr_ctl & (1UL << 27))
	245	op_add_pm(pmpc, kern, which, ctr, PM_STALLED);
	246
	247	/* Unfortunately, TAK is undefined on mispredicted branches.
	248	??? It is also undefined for non-cbranch insns, should
	249	check that. */
	250	if (!mispredict && pctr_ctl & (1UL << 0))
	251	op_add_pm(pmpc, kern, which, ctr, PM_TAKEN);
	252	}
	253
	254	struct op_axp_model op_model_ev67 = {
	255	.reg_setup = ev67_reg_setup,
	256	.cpu_setup = ev67_cpu_setup,
	257	.reset_ctr = ev67_reset_ctr,
	258	.handle_interrupt = ev67_handle_interrupt,
259	.cpu_type = "alpha/ev67",
260	.num_counters = 20,
261	.can_set_proc_mode = 0,
262	};