1/*
2 * Cell Broadband Engine OProfile Support
3 *
4 * (C) Copyright IBM Corporation 2006
5 *
6 * Author: David Erb (djerb@us.ibm.com)
7 * Modifications:
8 *	   Carl Love <carll@us.ibm.com>
9 *	   Maynard Johnson <maynardj@us.ibm.com>
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
15 */
16
17#include <linux/cpufreq.h>
18#include <linux/delay.h>
19#include <linux/jiffies.h>
20#include <linux/kthread.h>
21#include <linux/oprofile.h>
22#include <linux/percpu.h>
23#include <linux/smp.h>
24#include <linux/spinlock.h>
25#include <linux/timer.h>
26#include <asm/cell-pmu.h>
27#include <asm/cputable.h>
28#include <asm/firmware.h>
29#include <asm/io.h>
30#include <asm/oprofile_impl.h>
31#include <asm/processor.h>
32#include <asm/prom.h>
33#include <asm/ptrace.h>
34#include <asm/reg.h>
35#include <asm/rtas.h>
36#include <asm/cell-regs.h>
37
38#include "../platforms/cell/interrupt.h"
39#include "cell/pr_util.h"
40
41#define PPU_PROFILING            0
42#define SPU_PROFILING_CYCLES     1
43#define SPU_PROFILING_EVENTS     2
44
45#define SPU_EVENT_NUM_START      4100
46#define SPU_EVENT_NUM_STOP       4399
47#define SPU_PROFILE_EVENT_ADDR          4363  /* spu, address trace, decimal */
48#define SPU_PROFILE_EVENT_ADDR_MASK_A   0x146 /* sub unit set to zero */
49#define SPU_PROFILE_EVENT_ADDR_MASK_B   0x186 /* sub unit set to zero */
50
51#define NUM_SPUS_PER_NODE    8
52#define SPU_CYCLES_EVENT_NUM 2	/*  event number for SPU_CYCLES */
53
54#define PPU_CYCLES_EVENT_NUM 1	/*  event number for CYCLES */
55#define PPU_CYCLES_GRP_NUM   1	/* special group number for identifying
56				 * PPU_CYCLES event
57				 */
58#define CBE_COUNT_ALL_CYCLES 0x42800000 /* PPU cycle event specifier */
59
60#define NUM_THREADS 2         /* number of physical threads in
61			       * physical processor
62			       */
63#define NUM_DEBUG_BUS_WORDS 4
64#define NUM_INPUT_BUS_WORDS 2
65
66#define MAX_SPU_COUNT 0xFFFFFF	/* maximum 24 bit LFSR value */
67
68/* Minimum HW interval timer setting to send value to trace buffer is 10 cycle.
69 * To configure counter to send value every N cycles set counter to
70 * 2^32 - 1 - N.
71 */
72#define NUM_INTERVAL_CYC  0xFFFFFFFF - 10
73
74/*
75 * spu_cycle_reset is the number of cycles between samples.
76 * This variable is used for SPU profiling and should ONLY be set
77 * at the beginning of cell_reg_setup; otherwise, it's read-only.
78 */
79static unsigned int spu_cycle_reset;
80static unsigned int profiling_mode;
81static int spu_evnt_phys_spu_indx;
82
83struct pmc_cntrl_data {
84	unsigned long vcntr;
85	unsigned long evnts;
86	unsigned long masks;
87	unsigned long enabled;
88};
89
90/*
91 * ibm,cbe-perftools rtas parameters
92 */
93struct pm_signal {
94	u16 cpu;		/* Processor to modify */
95	u16 sub_unit;		/* hw subunit this applies to (if applicable)*/
96	short int signal_group; /* Signal Group to Enable/Disable */
97	u8 bus_word;		/* Enable/Disable on this Trace/Trigger/Event
98				 * Bus Word(s) (bitmask)
99				 */
100	u8 bit;			/* Trigger/Event bit (if applicable) */
101};
102
103/*
104 * rtas call arguments
105 */
106enum {
107	SUBFUNC_RESET = 1,
108	SUBFUNC_ACTIVATE = 2,
109	SUBFUNC_DEACTIVATE = 3,
110
111	PASSTHRU_IGNORE = 0,
112	PASSTHRU_ENABLE = 1,
113	PASSTHRU_DISABLE = 2,
114};
115
116struct pm_cntrl {
117	u16 enable;
118	u16 stop_at_max;
119	u16 trace_mode;
120	u16 freeze;
121	u16 count_mode;
122	u16 spu_addr_trace;
123	u8  trace_buf_ovflw;
124};
125
126static struct {
127	u32 group_control;
128	u32 debug_bus_control;
129	struct pm_cntrl pm_cntrl;
130	u32 pm07_cntrl[NR_PHYS_CTRS];
131} pm_regs;
132
133#define GET_SUB_UNIT(x) ((x & 0x0000f000) >> 12)
134#define GET_BUS_WORD(x) ((x & 0x000000f0) >> 4)
135#define GET_BUS_TYPE(x) ((x & 0x00000300) >> 8)
136#define GET_POLARITY(x) ((x & 0x00000002) >> 1)
137#define GET_COUNT_CYCLES(x) (x & 0x00000001)
138#define GET_INPUT_CONTROL(x) ((x & 0x00000004) >> 2)
139
140static DEFINE_PER_CPU(unsigned long[NR_PHYS_CTRS], pmc_values);
141static unsigned long spu_pm_cnt[MAX_NUMNODES * NUM_SPUS_PER_NODE];
142static struct pmc_cntrl_data pmc_cntrl[NUM_THREADS][NR_PHYS_CTRS];
143
144/*
145 * The CELL profiling code makes rtas calls to setup the debug bus to
146 * route the performance signals.  Additionally, SPU profiling requires
147 * a second rtas call to setup the hardware to capture the SPU PCs.
148 * The EIO error value is returned if the token lookups or the rtas
149 * call fail.  The EIO error number is the best choice of the existing
150 * error numbers.  The probability of rtas related error is very low.  But
151 * by returning EIO and printing additional information to dmsg the user
152 * will know that OProfile did not start and dmesg will tell them why.
153 * OProfile does not support returning errors on Stop.	Not a huge issue
154 * since failure to reset the debug bus or stop the SPU PC collection is
155 * not a fatel issue.  Chances are if the Stop failed, Start doesn't work
156 * either.
157 */
158
159/*
160 * Interpetation of hdw_thread:
161 * 0 - even virtual cpus 0, 2, 4,...
162 * 1 - odd virtual cpus 1, 3, 5, ...
163 *
164 * FIXME: this is strictly wrong, we need to clean this up in a number
165 * of places. It works for now. -arnd
166 */
167static u32 hdw_thread;
168
169static u32 virt_cntr_inter_mask;
170static struct timer_list timer_virt_cntr;
171static struct timer_list timer_spu_event_swap;
172
173/*
174 * pm_signal needs to be global since it is initialized in
175 * cell_reg_setup at the time when the necessary information
176 * is available.
177 */
178static struct pm_signal pm_signal[NR_PHYS_CTRS];
179static int pm_rtas_token;    /* token for debug bus setup call */
180static int spu_rtas_token;   /* token for SPU cycle profiling */
181
182static u32 reset_value[NR_PHYS_CTRS];
183static int num_counters;
184static int oprofile_running;
185static DEFINE_SPINLOCK(cntr_lock);
186
187static u32 ctr_enabled;
188
189static unsigned char input_bus[NUM_INPUT_BUS_WORDS];
190
191/*
192 * Firmware interface functions
193 */
194static int
195rtas_ibm_cbe_perftools(int subfunc, int passthru,
196		       void *address, unsigned long length)
197{
198	u64 paddr = __pa(address);
199
200	return rtas_call(pm_rtas_token, 5, 1, NULL, subfunc,
201			 passthru, paddr >> 32, paddr & 0xffffffff, length);
202}
203
204static void pm_rtas_reset_signals(u32 node)
205{
206	int ret;
207	struct pm_signal pm_signal_local;
208
209	/*
210	 * The debug bus is being set to the passthru disable state.
211	 * However, the FW still expects atleast one legal signal routing
212	 * entry or it will return an error on the arguments.	If we don't
213	 * supply a valid entry, we must ignore all return values.  Ignoring
214	 * all return values means we might miss an error we should be
215	 * concerned about.
216	 */
217
218	/*  fw expects physical cpu #. */
219	pm_signal_local.cpu = node;
220	pm_signal_local.signal_group = 21;
221	pm_signal_local.bus_word = 1;
222	pm_signal_local.sub_unit = 0;
223	pm_signal_local.bit = 0;
224
225	ret = rtas_ibm_cbe_perftools(SUBFUNC_RESET, PASSTHRU_DISABLE,
226				     &pm_signal_local,
227				     sizeof(struct pm_signal));
228
229	if (unlikely(ret))
230		/*
231		 * Not a fatal error. For Oprofile stop, the oprofile
232		 * functions do not support returning an error for
233		 * failure to stop OProfile.
234		 */
235		printk(KERN_WARNING "%s: rtas returned: %d\n",
236		       __func__, ret);
237}
238
239static int pm_rtas_activate_signals(u32 node, u32 count)
240{
241	int ret;
242	int i, j;
243	struct pm_signal pm_signal_local[NR_PHYS_CTRS];
244
245	/*
246	 * There is no debug setup required for the cycles event.
247	 * Note that only events in the same group can be used.
248	 * Otherwise, there will be conflicts in correctly routing
249	 * the signals on the debug bus.  It is the responsibility
250	 * of the OProfile user tool to check the events are in
251	 * the same group.
252	 */
253	i = 0;
254	for (j = 0; j < count; j++) {
255		if (pm_signal[j].signal_group != PPU_CYCLES_GRP_NUM) {
256
257			/* fw expects physical cpu # */
258			pm_signal_local[i].cpu = node;
259			pm_signal_local[i].signal_group
260				= pm_signal[j].signal_group;
261			pm_signal_local[i].bus_word = pm_signal[j].bus_word;
262			pm_signal_local[i].sub_unit = pm_signal[j].sub_unit;
263			pm_signal_local[i].bit = pm_signal[j].bit;
264			i++;
265		}
266	}
267
268	if (i != 0) {
269		ret = rtas_ibm_cbe_perftools(SUBFUNC_ACTIVATE, PASSTHRU_ENABLE,
270					     pm_signal_local,
271					     i * sizeof(struct pm_signal));
272
273		if (unlikely(ret)) {
274			printk(KERN_WARNING "%s: rtas returned: %d\n",
275			       __func__, ret);
276			return -EIO;
277		}
278	}
279
280	return 0;
281}
282
283/*
284 * PM Signal functions
285 */
286static void set_pm_event(u32 ctr, int event, u32 unit_mask)
287{
288	struct pm_signal *p;
289	u32 signal_bit;
290	u32 bus_word, bus_type, count_cycles, polarity, input_control;
291	int j, i;
292
293	if (event == PPU_CYCLES_EVENT_NUM) {
294		/* Special Event: Count all cpu cycles */
295		pm_regs.pm07_cntrl[ctr] = CBE_COUNT_ALL_CYCLES;
296		p = &(pm_signal[ctr]);
297		p->signal_group = PPU_CYCLES_GRP_NUM;
298		p->bus_word = 1;
299		p->sub_unit = 0;
300		p->bit = 0;
301		goto out;
302	} else {
303		pm_regs.pm07_cntrl[ctr] = 0;
304	}
305
306	bus_word = GET_BUS_WORD(unit_mask);
307	bus_type = GET_BUS_TYPE(unit_mask);
308	count_cycles = GET_COUNT_CYCLES(unit_mask);
309	polarity = GET_POLARITY(unit_mask);
310	input_control = GET_INPUT_CONTROL(unit_mask);
311	signal_bit = (event % 100);
312
313	p = &(pm_signal[ctr]);
314
315	p->signal_group = event / 100;
316	p->bus_word = bus_word;
317	p->sub_unit = GET_SUB_UNIT(unit_mask);
318
319	pm_regs.pm07_cntrl[ctr] = 0;
320	pm_regs.pm07_cntrl[ctr] |= PM07_CTR_COUNT_CYCLES(count_cycles);
321	pm_regs.pm07_cntrl[ctr] |= PM07_CTR_POLARITY(polarity);
322	pm_regs.pm07_cntrl[ctr] |= PM07_CTR_INPUT_CONTROL(input_control);
323
324	/*
325	 * Some of the islands signal selection is based on 64 bit words.
326	 * The debug bus words are 32 bits, the input words to the performance
327	 * counters are defined as 32 bits.  Need to convert the 64 bit island
328	 * specification to the appropriate 32 input bit and bus word for the
329	 * performance counter event selection.	 See the CELL Performance
330	 * monitoring signals manual and the Perf cntr hardware descriptions
331	 * for the details.
332	 */
333	if (input_control == 0) {
334		if (signal_bit > 31) {
335			signal_bit -= 32;
336			if (bus_word == 0x3)
337				bus_word = 0x2;
338			else if (bus_word == 0xc)
339				bus_word = 0x8;
340		}
341
342		if ((bus_type == 0) && p->signal_group >= 60)
343			bus_type = 2;
344		if ((bus_type == 1) && p->signal_group >= 50)
345			bus_type = 0;
346
347		pm_regs.pm07_cntrl[ctr] |= PM07_CTR_INPUT_MUX(signal_bit);
348	} else {
349		pm_regs.pm07_cntrl[ctr] = 0;
350		p->bit = signal_bit;
351	}
352
353	for (i = 0; i < NUM_DEBUG_BUS_WORDS; i++) {
354		if (bus_word & (1 << i)) {
355			pm_regs.debug_bus_control |=
356				(bus_type << (30 - (2 * i)));
357
358			for (j = 0; j < NUM_INPUT_BUS_WORDS; j++) {
359				if (input_bus[j] == 0xff) {
360					input_bus[j] = i;
361					pm_regs.group_control |=
362						(i << (30 - (2 * j)));
363
364					break;
365				}
366			}
367		}
368	}
369out:
370	;
371}
372
373static void write_pm_cntrl(int cpu)
374{
375	/*
376	 * Oprofile will use 32 bit counters, set bits 7:10 to 0
377	 * pmregs.pm_cntrl is a global
378	 */
379
380	u32 val = 0;
381	if (pm_regs.pm_cntrl.enable == 1)
382		val |= CBE_PM_ENABLE_PERF_MON;
383
384	if (pm_regs.pm_cntrl.stop_at_max == 1)
385		val |= CBE_PM_STOP_AT_MAX;
386
387	if (pm_regs.pm_cntrl.trace_mode != 0)
388		val |= CBE_PM_TRACE_MODE_SET(pm_regs.pm_cntrl.trace_mode);
389
390	if (pm_regs.pm_cntrl.trace_buf_ovflw == 1)
391		val |= CBE_PM_TRACE_BUF_OVFLW(pm_regs.pm_cntrl.trace_buf_ovflw);
392	if (pm_regs.pm_cntrl.freeze == 1)
393		val |= CBE_PM_FREEZE_ALL_CTRS;
394
395	val |= CBE_PM_SPU_ADDR_TRACE_SET(pm_regs.pm_cntrl.spu_addr_trace);
396
397	/*
398	 * Routine set_count_mode must be called previously to set
399	 * the count mode based on the user selection of user and kernel.
400	 */
401	val |= CBE_PM_COUNT_MODE_SET(pm_regs.pm_cntrl.count_mode);
402	cbe_write_pm(cpu, pm_control, val);
403}
404
405static inline void
406set_count_mode(u32 kernel, u32 user)
407{
408	/*
409	 * The user must specify user and kernel if they want them. If
410	 *  neither is specified, OProfile will count in hypervisor mode.
411	 *  pm_regs.pm_cntrl is a global
412	 */
413	if (kernel) {
414		if (user)
415			pm_regs.pm_cntrl.count_mode = CBE_COUNT_ALL_MODES;
416		else
417			pm_regs.pm_cntrl.count_mode =
418				CBE_COUNT_SUPERVISOR_MODE;
419	} else {
420		if (user)
421			pm_regs.pm_cntrl.count_mode = CBE_COUNT_PROBLEM_MODE;
422		else
423			pm_regs.pm_cntrl.count_mode =
424				CBE_COUNT_HYPERVISOR_MODE;
425	}
426}
427
428static inline void enable_ctr(u32 cpu, u32 ctr, u32 *pm07_cntrl)
429{
430
431	pm07_cntrl[ctr] |= CBE_PM_CTR_ENABLE;
432	cbe_write_pm07_control(cpu, ctr, pm07_cntrl[ctr]);
433}
434
435/*
436 * Oprofile is expected to collect data on all CPUs simultaneously.
437 * However, there is one set of performance counters per node.	There are
438 * two hardware threads or virtual CPUs on each node.  Hence, OProfile must
439 * multiplex in time the performance counter collection on the two virtual
440 * CPUs.  The multiplexing of the performance counters is done by this
441 * virtual counter routine.
442 *
443 * The pmc_values used below is defined as 'per-cpu' but its use is
444 * more akin to 'per-node'.  We need to store two sets of counter
445 * values per node -- one for the previous run and one for the next.
446 * The per-cpu[NR_PHYS_CTRS] gives us the storage we need.  Each odd/even
447 * pair of per-cpu arrays is used for storing the previous and next
448 * pmc values for a given node.
449 * NOTE: We use the per-cpu variable to improve cache performance.
450 *
451 * This routine will alternate loading the virtual counters for
452 * virtual CPUs
453 */
454static void cell_virtual_cntr(unsigned long data)
455{
456	int i, prev_hdw_thread, next_hdw_thread;
457	u32 cpu;
458	unsigned long flags;
459
460	/*
461	 * Make sure that the interrupt_hander and the virt counter are
462	 * not both playing with the counters on the same node.
463	 */
464
465	spin_lock_irqsave(&cntr_lock, flags);
466
467	prev_hdw_thread = hdw_thread;
468
469	/* switch the cpu handling the interrupts */
470	hdw_thread = 1 ^ hdw_thread;
471	next_hdw_thread = hdw_thread;
472
473	pm_regs.group_control = 0;
474	pm_regs.debug_bus_control = 0;
475
476	for (i = 0; i < NUM_INPUT_BUS_WORDS; i++)
477		input_bus[i] = 0xff;
478
479	/*
480	 * There are some per thread events.  Must do the
481	 * set event, for the thread that is being started
482	 */
483	for (i = 0; i < num_counters; i++)
484		set_pm_event(i,
485			pmc_cntrl[next_hdw_thread][i].evnts,
486			pmc_cntrl[next_hdw_thread][i].masks);
487
488	/*
489	 * The following is done only once per each node, but
490	 * we need cpu #, not node #, to pass to the cbe_xxx functions.
491	 */
492	for_each_online_cpu(cpu) {
493		if (cbe_get_hw_thread_id(cpu))
494			continue;
495
496		/*
497		 * stop counters, save counter values, restore counts
498		 * for previous thread
499		 */
500		cbe_disable_pm(cpu);
501		cbe_disable_pm_interrupts(cpu);
502		for (i = 0; i < num_counters; i++) {
503			per_cpu(pmc_values, cpu + prev_hdw_thread)[i]
504				= cbe_read_ctr(cpu, i);
505
506			if (per_cpu(pmc_values, cpu + next_hdw_thread)[i]
507			    == 0xFFFFFFFF)
508				/* If the cntr value is 0xffffffff, we must
509				 * reset that to 0xfffffff0 when the current
510				 * thread is restarted.	 This will generate a
511				 * new interrupt and make sure that we never
512				 * restore the counters to the max value.  If
513				 * the counters were restored to the max value,
514				 * they do not increment and no interrupts are
515				 * generated.  Hence no more samples will be
516				 * collected on that cpu.
517				 */
518				cbe_write_ctr(cpu, i, 0xFFFFFFF0);
519			else
520				cbe_write_ctr(cpu, i,
521					      per_cpu(pmc_values,
522						      cpu +
523						      next_hdw_thread)[i]);
524		}
525
526		/*
527		 * Switch to the other thread. Change the interrupt
528		 * and control regs to be scheduled on the CPU
529		 * corresponding to the thread to execute.
530		 */
531		for (i = 0; i < num_counters; i++) {
532			if (pmc_cntrl[next_hdw_thread][i].enabled) {
533				/*
534				 * There are some per thread events.
535				 * Must do the set event, enable_cntr
536				 * for each cpu.
537				 */
538				enable_ctr(cpu, i,
539					   pm_regs.pm07_cntrl);
540			} else {
541				cbe_write_pm07_control(cpu, i, 0);
542			}
543		}
544
545		/* Enable interrupts on the CPU thread that is starting */
546		cbe_enable_pm_interrupts(cpu, next_hdw_thread,
547					 virt_cntr_inter_mask);
548		cbe_enable_pm(cpu);
549	}
550
551	spin_unlock_irqrestore(&cntr_lock, flags);
552
553	mod_timer(&timer_virt_cntr, jiffies + HZ / 10);
554}
555
556static void start_virt_cntrs(void)
557{
558	init_timer(&timer_virt_cntr);
559	timer_virt_cntr.function = cell_virtual_cntr;
560	timer_virt_cntr.data = 0UL;
561	timer_virt_cntr.expires = jiffies + HZ / 10;
562	add_timer(&timer_virt_cntr);
563}
564
565static int cell_reg_setup_spu_cycles(struct op_counter_config *ctr,
566			struct op_system_config *sys, int num_ctrs)
567{
568	spu_cycle_reset = ctr[0].count;
569
570	/*
571	 * Each node will need to make the rtas call to start
572	 * and stop SPU profiling.  Get the token once and store it.
573	 */
574	spu_rtas_token = rtas_token("ibm,cbe-spu-perftools");
575
576	if (unlikely(spu_rtas_token == RTAS_UNKNOWN_SERVICE)) {
577		printk(KERN_ERR
578		       "%s: rtas token ibm,cbe-spu-perftools unknown\n",
579		       __func__);
580		return -EIO;
581	}
582	return 0;
583}
584
585/* Unfortunately, the hardware will only support event profiling
586 * on one SPU per node at a time.  Therefore, we must time slice
587 * the profiling across all SPUs in the node.  Note, we do this
588 * in parallel for each node.  The following routine is called
589 * periodically based on kernel timer to switch which SPU is
590 * being monitored in a round robbin fashion.
591 */
592static void spu_evnt_swap(unsigned long data)
593{
594	int node;
595	int cur_phys_spu, nxt_phys_spu, cur_spu_evnt_phys_spu_indx;
596	unsigned long flags;
597	int cpu;
598	int ret;
599	u32 interrupt_mask;
600
601
602	/* enable interrupts on cntr 0 */
603	interrupt_mask = CBE_PM_CTR_OVERFLOW_INTR(0);
604
605	hdw_thread = 0;
606
607	/* Make sure spu event interrupt handler and spu event swap
608	 * don't access the counters simultaneously.
609	 */
610	spin_lock_irqsave(&cntr_lock, flags);
611
612	cur_spu_evnt_phys_spu_indx = spu_evnt_phys_spu_indx;
613
614	if (++(spu_evnt_phys_spu_indx) == NUM_SPUS_PER_NODE)
615		spu_evnt_phys_spu_indx = 0;
616
617	pm_signal[0].sub_unit = spu_evnt_phys_spu_indx;
618	pm_signal[1].sub_unit = spu_evnt_phys_spu_indx;
619	pm_signal[2].sub_unit = spu_evnt_phys_spu_indx;
620
621	/* switch the SPU being profiled on each node */
622	for_each_online_cpu(cpu) {
623		if (cbe_get_hw_thread_id(cpu))
624			continue;
625
626		node = cbe_cpu_to_node(cpu);
627		cur_phys_spu = (node * NUM_SPUS_PER_NODE)
628			+ cur_spu_evnt_phys_spu_indx;
629		nxt_phys_spu = (node * NUM_SPUS_PER_NODE)
630			+ spu_evnt_phys_spu_indx;
631
632		/*
633		 * stop counters, save counter values, restore counts
634		 * for previous physical SPU
635		 */
636		cbe_disable_pm(cpu);
637		cbe_disable_pm_interrupts(cpu);
638
639		spu_pm_cnt[cur_phys_spu]
640			= cbe_read_ctr(cpu, 0);
641
642		/* restore previous count for the next spu to sample */
643		/* NOTE, hardware issue, counter will not start if the
644		 * counter value is at max (0xFFFFFFFF).
645		 */
646		if (spu_pm_cnt[nxt_phys_spu] >= 0xFFFFFFFF)
647			cbe_write_ctr(cpu, 0, 0xFFFFFFF0);
648		 else
649			 cbe_write_ctr(cpu, 0, spu_pm_cnt[nxt_phys_spu]);
650
651		pm_rtas_reset_signals(cbe_cpu_to_node(cpu));
652
653		/* setup the debug bus measure the one event and
654		 * the two events to route the next SPU's PC on
655		 * the debug bus
656		 */
657		ret = pm_rtas_activate_signals(cbe_cpu_to_node(cpu), 3);
658		if (ret)
659			printk(KERN_ERR "%s: pm_rtas_activate_signals failed, "
660			       "SPU event swap\n", __func__);
661
662		/* clear the trace buffer, don't want to take PC for
663		 * previous SPU*/
664		cbe_write_pm(cpu, trace_address, 0);
665
666		enable_ctr(cpu, 0, pm_regs.pm07_cntrl);
667
668		/* Enable interrupts on the CPU thread that is starting */
669		cbe_enable_pm_interrupts(cpu, hdw_thread,
670					 interrupt_mask);
671		cbe_enable_pm(cpu);
672	}
673
674	spin_unlock_irqrestore(&cntr_lock, flags);
675
676	/* swap approximately every 0.1 seconds */
677	mod_timer(&timer_spu_event_swap, jiffies + HZ / 25);
678}
679
680static void start_spu_event_swap(void)
681{
682	init_timer(&timer_spu_event_swap);
683	timer_spu_event_swap.function = spu_evnt_swap;
684	timer_spu_event_swap.data = 0UL;
685	timer_spu_event_swap.expires = jiffies + HZ / 25;
686	add_timer(&timer_spu_event_swap);
687}
688
689static int cell_reg_setup_spu_events(struct op_counter_config *ctr,
690			struct op_system_config *sys, int num_ctrs)
691{
692	int i;
693
694	/* routine is called once for all nodes */
695
696	spu_evnt_phys_spu_indx = 0;
697	/*
698	 * For all events except PPU CYCLEs, each node will need to make
699	 * the rtas cbe-perftools call to setup and reset the debug bus.
700	 * Make the token lookup call once and store it in the global
701	 * variable pm_rtas_token.
702	 */
703	pm_rtas_token = rtas_token("ibm,cbe-perftools");
704
705	if (unlikely(pm_rtas_token == RTAS_UNKNOWN_SERVICE)) {
706		printk(KERN_ERR
707		       "%s: rtas token ibm,cbe-perftools unknown\n",
708		       __func__);
709		return -EIO;
710	}
711
712	/* setup the pm_control register settings,
713	 * settings will be written per node by the
714	 * cell_cpu_setup() function.
715	 */
716	pm_regs.pm_cntrl.trace_buf_ovflw = 1;
717
718	/* Use the occurrence trace mode to have SPU PC saved
719	 * to the trace buffer.  Occurrence data in trace buffer
720	 * is not used.  Bit 2 must be set to store SPU addresses.
721	 */
722	pm_regs.pm_cntrl.trace_mode = 2;
723
724	pm_regs.pm_cntrl.spu_addr_trace = 0x1;  /* using debug bus
725						   event 2 & 3 */
726
727	/* setup the debug bus event array with the SPU PC routing events.
728	*  Note, pm_signal[0] will be filled in by set_pm_event() call below.
729	*/
730	pm_signal[1].signal_group = SPU_PROFILE_EVENT_ADDR / 100;
731	pm_signal[1].bus_word = GET_BUS_WORD(SPU_PROFILE_EVENT_ADDR_MASK_A);
732	pm_signal[1].bit = SPU_PROFILE_EVENT_ADDR % 100;
733	pm_signal[1].sub_unit = spu_evnt_phys_spu_indx;
734
735	pm_signal[2].signal_group = SPU_PROFILE_EVENT_ADDR / 100;
736	pm_signal[2].bus_word = GET_BUS_WORD(SPU_PROFILE_EVENT_ADDR_MASK_B);
737	pm_signal[2].bit = SPU_PROFILE_EVENT_ADDR % 100;
738	pm_signal[2].sub_unit = spu_evnt_phys_spu_indx;
739
740	/* Set the user selected spu event to profile on,
741	 * note, only one SPU profiling event is supported
742	 */
743	num_counters = 1;  /* Only support one SPU event at a time */
744	set_pm_event(0, ctr[0].event, ctr[0].unit_mask);
745
746	reset_value[0] = 0xFFFFFFFF - ctr[0].count;
747
748	/* global, used by cell_cpu_setup */
749	ctr_enabled |= 1;
750
751	/* Initialize the count for each SPU to the reset value */
752	for (i=0; i < MAX_NUMNODES * NUM_SPUS_PER_NODE; i++)
753		spu_pm_cnt[i] = reset_value[0];
754
755	return 0;
756}
757
758static int cell_reg_setup_ppu(struct op_counter_config *ctr,
759			struct op_system_config *sys, int num_ctrs)
760{
761	/* routine is called once for all nodes */
762	int i, j, cpu;
763
764	num_counters = num_ctrs;
765
766	if (unlikely(num_ctrs > NR_PHYS_CTRS)) {
767		printk(KERN_ERR
768		       "%s: Oprofile, number of specified events " \
769		       "exceeds number of physical counters\n",
770		       __func__);
771		return -EIO;
772	}
773
774	set_count_mode(sys->enable_kernel, sys->enable_user);
775
776	/* Setup the thread 0 events */
777	for (i = 0; i < num_ctrs; ++i) {
778
779		pmc_cntrl[0][i].evnts = ctr[i].event;
780		pmc_cntrl[0][i].masks = ctr[i].unit_mask;
781		pmc_cntrl[0][i].enabled = ctr[i].enabled;
782		pmc_cntrl[0][i].vcntr = i;
783
784		for_each_possible_cpu(j)
785			per_cpu(pmc_values, j)[i] = 0;
786	}
787
788	/*
789	 * Setup the thread 1 events, map the thread 0 event to the
790	 * equivalent thread 1 event.
791	 */
792	for (i = 0; i < num_ctrs; ++i) {
793		if ((ctr[i].event >= 2100) && (ctr[i].event <= 2111))
794			pmc_cntrl[1][i].evnts = ctr[i].event + 19;
795		else if (ctr[i].event == 2203)
796			pmc_cntrl[1][i].evnts = ctr[i].event;
797		else if ((ctr[i].event >= 2200) && (ctr[i].event <= 2215))
798			pmc_cntrl[1][i].evnts = ctr[i].event + 16;
799		else
800			pmc_cntrl[1][i].evnts = ctr[i].event;
801
802		pmc_cntrl[1][i].masks = ctr[i].unit_mask;
803		pmc_cntrl[1][i].enabled = ctr[i].enabled;
804		pmc_cntrl[1][i].vcntr = i;
805	}
806
807	for (i = 0; i < NUM_INPUT_BUS_WORDS; i++)
808		input_bus[i] = 0xff;
809
810	/*
811	 * Our counters count up, and "count" refers to
812	 * how much before the next interrupt, and we interrupt
813	 * on overflow.	 So we calculate the starting value
814	 * which will give us "count" until overflow.
815	 * Then we set the events on the enabled counters.
816	 */
817	for (i = 0; i < num_counters; ++i) {
818		/* start with virtual counter set 0 */
819		if (pmc_cntrl[0][i].enabled) {
820			/* Using 32bit counters, reset max - count */
821			reset_value[i] = 0xFFFFFFFF - ctr[i].count;
822			set_pm_event(i,
823				     pmc_cntrl[0][i].evnts,
824				     pmc_cntrl[0][i].masks);
825
826			/* global, used by cell_cpu_setup */
827			ctr_enabled |= (1 << i);
828		}
829	}
830
831	/* initialize the previous counts for the virtual cntrs */
832	for_each_online_cpu(cpu)
833		for (i = 0; i < num_counters; ++i) {
834			per_cpu(pmc_values, cpu)[i] = reset_value[i];
835		}
836
837	return 0;
838}
839
840
841/* This function is called once for all cpus combined */
842static int cell_reg_setup(struct op_counter_config *ctr,
843			struct op_system_config *sys, int num_ctrs)
844{
845	int ret=0;
846	spu_cycle_reset = 0;
847
848	/* initialize the spu_arr_trace value, will be reset if
849	 * doing spu event profiling.
850	 */
851	pm_regs.group_control = 0;
852	pm_regs.debug_bus_control = 0;
853	pm_regs.pm_cntrl.stop_at_max = 1;
854	pm_regs.pm_cntrl.trace_mode = 0;
855	pm_regs.pm_cntrl.freeze = 1;
856	pm_regs.pm_cntrl.trace_buf_ovflw = 0;
857	pm_regs.pm_cntrl.spu_addr_trace = 0;
858
859	/*
860	 * For all events except PPU CYCLEs, each node will need to make
861	 * the rtas cbe-perftools call to setup and reset the debug bus.
862	 * Make the token lookup call once and store it in the global
863	 * variable pm_rtas_token.
864	 */
865	pm_rtas_token = rtas_token("ibm,cbe-perftools");
866
867	if (unlikely(pm_rtas_token == RTAS_UNKNOWN_SERVICE)) {
868		printk(KERN_ERR
869		       "%s: rtas token ibm,cbe-perftools unknown\n",
870		       __func__);
871		return -EIO;
872	}
873
874	if (ctr[0].event == SPU_CYCLES_EVENT_NUM) {
875		profiling_mode = SPU_PROFILING_CYCLES;
876		ret = cell_reg_setup_spu_cycles(ctr, sys, num_ctrs);
877	} else if ((ctr[0].event >= SPU_EVENT_NUM_START) &&
878		   (ctr[0].event <= SPU_EVENT_NUM_STOP)) {
879		profiling_mode = SPU_PROFILING_EVENTS;
880		spu_cycle_reset = ctr[0].count;
881
882		/* for SPU event profiling, need to setup the
883		 * pm_signal array with the events to route the
884		 * SPU PC before making the FW call.  Note, only
885		 * one SPU event for profiling can be specified
886		 * at a time.
887		 */
888		cell_reg_setup_spu_events(ctr, sys, num_ctrs);
889	} else {
890		profiling_mode = PPU_PROFILING;
891		ret = cell_reg_setup_ppu(ctr, sys, num_ctrs);
892	}
893
894	return ret;
895}
896
897
898
899/* This function is called once for each cpu */
900static int cell_cpu_setup(struct op_counter_config *cntr)
901{
902	u32 cpu = smp_processor_id();
903	u32 num_enabled = 0;
904	int i;
905	int ret;
906
907	/* Cycle based SPU profiling does not use the performance
908	 * counters.  The trace array is configured to collect
909	 * the data.
910	 */
911	if (profiling_mode == SPU_PROFILING_CYCLES)
912		return 0;
913
914	/* There is one performance monitor per processor chip (i.e. node),
915	 * so we only need to perform this function once per node.
916	 */
917	if (cbe_get_hw_thread_id(cpu))
918		return 0;
919
920	/* Stop all counters */
921	cbe_disable_pm(cpu);
922	cbe_disable_pm_interrupts(cpu);
923
924	cbe_write_pm(cpu, pm_start_stop, 0);
925	cbe_write_pm(cpu, group_control, pm_regs.group_control);
926	cbe_write_pm(cpu, debug_bus_control, pm_regs.debug_bus_control);
927	write_pm_cntrl(cpu);
928
929	for (i = 0; i < num_counters; ++i) {
930		if (ctr_enabled & (1 << i)) {
931			pm_signal[num_enabled].cpu = cbe_cpu_to_node(cpu);
932			num_enabled++;
933		}
934	}
935
936	/*
937	 * The pm_rtas_activate_signals will return -EIO if the FW
938	 * call failed.
939	 */
940	if (profiling_mode == SPU_PROFILING_EVENTS) {
941		/* For SPU event profiling also need to setup the
942		 * pm interval timer
943		 */
944		ret = pm_rtas_activate_signals(cbe_cpu_to_node(cpu),
945					       num_enabled+2);
946		/* store PC from debug bus to Trace buffer as often
947		 * as possible (every 10 cycles)
948		 */
949		cbe_write_pm(cpu, pm_interval, NUM_INTERVAL_CYC);
950		return ret;
951	} else
952		return pm_rtas_activate_signals(cbe_cpu_to_node(cpu),
953						num_enabled);
954}
955
956#define ENTRIES	 303
957#define MAXLFSR	 0xFFFFFF
958
959/* precomputed table of 24 bit LFSR values */
960static int initial_lfsr[] = {
961 8221349, 12579195, 5379618, 10097839, 7512963, 7519310, 3955098, 10753424,
962 15507573, 7458917, 285419, 2641121, 9780088, 3915503, 6668768, 1548716,
963 4885000, 8774424, 9650099, 2044357, 2304411, 9326253, 10332526, 4421547,
964 3440748, 10179459, 13332843, 10375561, 1313462, 8375100, 5198480, 6071392,
965 9341783, 1526887, 3985002, 1439429, 13923762, 7010104, 11969769, 4547026,
966 2040072, 4025602, 3437678, 7939992, 11444177, 4496094, 9803157, 10745556,
967 3671780, 4257846, 5662259, 13196905, 3237343, 12077182, 16222879, 7587769,
968 14706824, 2184640, 12591135, 10420257, 7406075, 3648978, 11042541, 15906893,
969 11914928, 4732944, 10695697, 12928164, 11980531, 4430912, 11939291, 2917017,
970 6119256, 4172004, 9373765, 8410071, 14788383, 5047459, 5474428, 1737756,
971 15967514, 13351758, 6691285, 8034329, 2856544, 14394753, 11310160, 12149558,
972 7487528, 7542781, 15668898, 12525138, 12790975, 3707933, 9106617, 1965401,
973 16219109, 12801644, 2443203, 4909502, 8762329, 3120803, 6360315, 9309720,
974 15164599, 10844842, 4456529, 6667610, 14924259, 884312, 6234963, 3326042,
975 15973422, 13919464, 5272099, 6414643, 3909029, 2764324, 5237926, 4774955,
976 10445906, 4955302, 5203726, 10798229, 11443419, 2303395, 333836, 9646934,
977 3464726, 4159182, 568492, 995747, 10318756, 13299332, 4836017, 8237783,
978 3878992, 2581665, 11394667, 5672745, 14412947, 3159169, 9094251, 16467278,
979 8671392, 15230076, 4843545, 7009238, 15504095, 1494895, 9627886, 14485051,
980 8304291, 252817, 12421642, 16085736, 4774072, 2456177, 4160695, 15409741,
981 4902868, 5793091, 13162925, 16039714, 782255, 11347835, 14884586, 366972,
982 16308990, 11913488, 13390465, 2958444, 10340278, 1177858, 1319431, 10426302,
983 2868597, 126119, 5784857, 5245324, 10903900, 16436004, 3389013, 1742384,
984 14674502, 10279218, 8536112, 10364279, 6877778, 14051163, 1025130, 6072469,
985 1988305, 8354440, 8216060, 16342977, 13112639, 3976679, 5913576, 8816697,
986 6879995, 14043764, 3339515, 9364420, 15808858, 12261651, 2141560, 5636398,
987 10345425, 10414756, 781725, 6155650, 4746914, 5078683, 7469001, 6799140,
988 10156444, 9667150, 10116470, 4133858, 2121972, 1124204, 1003577, 1611214,
989 14304602, 16221850, 13878465, 13577744, 3629235, 8772583, 10881308, 2410386,
990 7300044, 5378855, 9301235, 12755149, 4977682, 8083074, 10327581, 6395087,
991 9155434, 15501696, 7514362, 14520507, 15808945, 3244584, 4741962, 9658130,
992 14336147, 8654727, 7969093, 15759799, 14029445, 5038459, 9894848, 8659300,
993 13699287, 8834306, 10712885, 14753895, 10410465, 3373251, 309501, 9561475,
994 5526688, 14647426, 14209836, 5339224, 207299, 14069911, 8722990, 2290950,
995 3258216, 12505185, 6007317, 9218111, 14661019, 10537428, 11731949, 9027003,
996 6641507, 9490160, 200241, 9720425, 16277895, 10816638, 1554761, 10431375,
997 7467528, 6790302, 3429078, 14633753, 14428997, 11463204, 3576212, 2003426,
998 6123687, 820520, 9992513, 15784513, 5778891, 6428165, 8388607
999};
1000
1001/*
1002 * The hardware uses an LFSR counting sequence to determine when to capture
1003 * the SPU PCs.	 An LFSR sequence is like a puesdo random number sequence
1004 * where each number occurs once in the sequence but the sequence is not in
1005 * numerical order. The SPU PC capture is done when the LFSR sequence reaches
1006 * the last value in the sequence.  Hence the user specified value N
1007 * corresponds to the LFSR number that is N from the end of the sequence.
1008 *
1009 * To avoid the time to compute the LFSR, a lookup table is used.  The 24 bit
1010 * LFSR sequence is broken into four ranges.  The spacing of the precomputed
1011 * values is adjusted in each range so the error between the user specifed
1012 * number (N) of events between samples and the actual number of events based
1013 * on the precomputed value will be les then about 6.2%.  Note, if the user
1014 * specifies N < 2^16, the LFSR value that is 2^16 from the end will be used.
1015 * This is to prevent the loss of samples because the trace buffer is full.
1016 *
1017 *	   User specified N		     Step between	   Index in
1018 *					 precomputed values	 precomputed
1019 *								    table
1020 * 0		    to	2^16-1			----		      0
1021 * 2^16	    to	2^16+2^19-1		2^12		    1 to 128
1022 * 2^16+2^19	    to	2^16+2^19+2^22-1	2^15		  129 to 256
1023 * 2^16+2^19+2^22  to	2^24-1			2^18		  257 to 302
1024 *
1025 *
1026 * For example, the LFSR values in the second range are computed for 2^16,
1027 * 2^16+2^12, ... , 2^19-2^16, 2^19 and stored in the table at indicies
1028 * 1, 2,..., 127, 128.
1029 *
1030 * The 24 bit LFSR value for the nth number in the sequence can be
1031 * calculated using the following code:
1032 *
1033 * #define size 24
1034 * int calculate_lfsr(int n)
1035 * {
1036 *	int i;
1037 *	unsigned int newlfsr0;
1038 *	unsigned int lfsr = 0xFFFFFF;
1039 *	unsigned int howmany = n;
1040 *
1041 *	for (i = 2; i < howmany + 2; i++) {
1042 *		newlfsr0 = (((lfsr >> (size - 1 - 0)) & 1) ^
1043 *		((lfsr >> (size - 1 - 1)) & 1) ^
1044 *		(((lfsr >> (size - 1 - 6)) & 1) ^
1045 *		((lfsr >> (size - 1 - 23)) & 1)));
1046 *
1047 *		lfsr >>= 1;
1048 *		lfsr = lfsr | (newlfsr0 << (size - 1));
1049 *	}
1050 *	return lfsr;
1051 * }
1052 */
1053
1054#define V2_16  (0x1 << 16)
1055#define V2_19  (0x1 << 19)
1056#define V2_22  (0x1 << 22)
1057
1058static int calculate_lfsr(int n)
1059{
1060	/*
1061	 * The ranges and steps are in powers of 2 so the calculations
1062	 * can be done using shifts rather then divide.
1063	 */
1064	int index;
1065
1066	if ((n >> 16) == 0)
1067		index = 0;
1068	else if (((n - V2_16) >> 19) == 0)
1069		index = ((n - V2_16) >> 12) + 1;
1070	else if (((n - V2_16 - V2_19) >> 22) == 0)
1071		index = ((n - V2_16 - V2_19) >> 15 ) + 1 + 128;
1072	else if (((n - V2_16 - V2_19 - V2_22) >> 24) == 0)
1073		index = ((n - V2_16 - V2_19 - V2_22) >> 18 ) + 1 + 256;
1074	else
1075		index = ENTRIES-1;
1076
1077	/* make sure index is valid */
1078	if ((index >= ENTRIES) || (index < 0))
1079		index = ENTRIES-1;
1080
1081	return initial_lfsr[index];
1082}
1083
1084static int pm_rtas_activate_spu_profiling(u32 node)
1085{
1086	int ret, i;
1087	struct pm_signal pm_signal_local[NUM_SPUS_PER_NODE];
1088
1089	/*
1090	 * Set up the rtas call to configure the debug bus to
1091	 * route the SPU PCs.  Setup the pm_signal for each SPU
1092	 */
1093	for (i = 0; i < ARRAY_SIZE(pm_signal_local); i++) {
1094		pm_signal_local[i].cpu = node;
1095		pm_signal_local[i].signal_group = 41;
1096		/* spu i on word (i/2) */
1097		pm_signal_local[i].bus_word = 1 << i / 2;
1098		/* spu i */
1099		pm_signal_local[i].sub_unit = i;
1100		pm_signal_local[i].bit = 63;
1101	}
1102
1103	ret = rtas_ibm_cbe_perftools(SUBFUNC_ACTIVATE,
1104				     PASSTHRU_ENABLE, pm_signal_local,
1105				     (ARRAY_SIZE(pm_signal_local)
1106				      * sizeof(struct pm_signal)));
1107
1108	if (unlikely(ret)) {
1109		printk(KERN_WARNING "%s: rtas returned: %d\n",
1110		       __func__, ret);
1111		return -EIO;
1112	}
1113
1114	return 0;
1115}
1116
1117#ifdef CONFIG_CPU_FREQ
1118static int
1119oprof_cpufreq_notify(struct notifier_block *nb, unsigned long val, void *data)
1120{
1121	int ret = 0;
1122	struct cpufreq_freqs *frq = data;
1123	if ((val == CPUFREQ_PRECHANGE && frq->old < frq->new) ||
1124	    (val == CPUFREQ_POSTCHANGE && frq->old > frq->new))
1125		set_spu_profiling_frequency(frq->new, spu_cycle_reset);
1126	return ret;
1127}
1128
1129static struct notifier_block cpu_freq_notifier_block = {
1130	.notifier_call	= oprof_cpufreq_notify
1131};
1132#endif
1133
1134/*
1135 * Note the generic OProfile stop calls do not support returning
1136 * an error on stop.  Hence, will not return an error if the FW
1137 * calls fail on stop.	Failure to reset the debug bus is not an issue.
1138 * Failure to disable the SPU profiling is not an issue.  The FW calls
1139 * to enable the performance counters and debug bus will work even if
1140 * the hardware was not cleanly reset.
1141 */
1142static void cell_global_stop_spu_cycles(void)
1143{
1144	int subfunc, rtn_value;
1145	unsigned int lfsr_value;
1146	int cpu;
1147
1148	oprofile_running = 0;
1149	smp_wmb();
1150
1151#ifdef CONFIG_CPU_FREQ
1152	cpufreq_unregister_notifier(&cpu_freq_notifier_block,
1153				    CPUFREQ_TRANSITION_NOTIFIER);
1154#endif
1155
1156	for_each_online_cpu(cpu) {
1157		if (cbe_get_hw_thread_id(cpu))
1158			continue;
1159
1160		subfunc = 3;	/*
1161				 * 2 - activate SPU tracing,
1162				 * 3 - deactivate
1163				 */
1164		lfsr_value = 0x8f100000;
1165
1166		rtn_value = rtas_call(spu_rtas_token, 3, 1, NULL,
1167				      subfunc, cbe_cpu_to_node(cpu),
1168				      lfsr_value);
1169
1170		if (unlikely(rtn_value != 0)) {
1171			printk(KERN_ERR
1172			       "%s: rtas call ibm,cbe-spu-perftools " \
1173			       "failed, return = %d\n",
1174			       __func__, rtn_value);
1175		}
1176
1177		/* Deactivate the signals */
1178		pm_rtas_reset_signals(cbe_cpu_to_node(cpu));
1179	}
1180
1181	stop_spu_profiling_cycles();
1182}
1183
1184static void cell_global_stop_spu_events(void)
1185{
1186	int cpu;
1187	oprofile_running = 0;
1188
1189	stop_spu_profiling_events();
1190	smp_wmb();
1191
1192	for_each_online_cpu(cpu) {
1193		if (cbe_get_hw_thread_id(cpu))
1194			continue;
1195
1196		cbe_sync_irq(cbe_cpu_to_node(cpu));
1197		/* Stop the counters */
1198		cbe_disable_pm(cpu);
1199		cbe_write_pm07_control(cpu, 0, 0);
1200
1201		/* Deactivate the signals */
1202		pm_rtas_reset_signals(cbe_cpu_to_node(cpu));
1203
1204		/* Deactivate interrupts */
1205		cbe_disable_pm_interrupts(cpu);
1206	}
1207	del_timer_sync(&timer_spu_event_swap);
1208}
1209
1210static void cell_global_stop_ppu(void)
1211{
1212	int cpu;
1213
1214	/*
1215	 * This routine will be called once for the system.
1216	 * There is one performance monitor per node, so we
1217	 * only need to perform this function once per node.
1218	 */
1219	del_timer_sync(&timer_virt_cntr);
1220	oprofile_running = 0;
1221	smp_wmb();
1222
1223	for_each_online_cpu(cpu) {
1224		if (cbe_get_hw_thread_id(cpu))
1225			continue;
1226
1227		cbe_sync_irq(cbe_cpu_to_node(cpu));
1228		/* Stop the counters */
1229		cbe_disable_pm(cpu);
1230
1231		/* Deactivate the signals */
1232		pm_rtas_reset_signals(cbe_cpu_to_node(cpu));
1233
1234		/* Deactivate interrupts */
1235		cbe_disable_pm_interrupts(cpu);
1236	}
1237}
1238
1239static void cell_global_stop(void)
1240{
1241	if (profiling_mode == PPU_PROFILING)
1242		cell_global_stop_ppu();
1243	else if (profiling_mode == SPU_PROFILING_EVENTS)
1244		cell_global_stop_spu_events();
1245	else
1246		cell_global_stop_spu_cycles();
1247}
1248
1249static int cell_global_start_spu_cycles(struct op_counter_config *ctr)
1250{
1251	int subfunc;
1252	unsigned int lfsr_value;
1253	int cpu;
1254	int ret;
1255	int rtas_error;
1256	unsigned int cpu_khzfreq = 0;
1257
1258	/* The SPU profiling uses time-based profiling based on
1259	 * cpu frequency, so if configured with the CPU_FREQ
1260	 * option, we should detect frequency changes and react
1261	 * accordingly.
1262	 */
1263#ifdef CONFIG_CPU_FREQ
1264	ret = cpufreq_register_notifier(&cpu_freq_notifier_block,
1265					CPUFREQ_TRANSITION_NOTIFIER);
1266	if (ret < 0)
1267		/* this is not a fatal error */
1268		printk(KERN_ERR "CPU freq change registration failed: %d\n",
1269		       ret);
1270
1271	else
1272		cpu_khzfreq = cpufreq_quick_get(smp_processor_id());
1273#endif
1274
1275	set_spu_profiling_frequency(cpu_khzfreq, spu_cycle_reset);
1276
1277	for_each_online_cpu(cpu) {
1278		if (cbe_get_hw_thread_id(cpu))
1279			continue;
1280
1281		/*
1282		 * Setup SPU cycle-based profiling.
1283		 * Set perf_mon_control bit 0 to a zero before
1284		 * enabling spu collection hardware.
1285		 */
1286		cbe_write_pm(cpu, pm_control, 0);
1287
1288		if (spu_cycle_reset > MAX_SPU_COUNT)
1289			/* use largest possible value */
1290			lfsr_value = calculate_lfsr(MAX_SPU_COUNT-1);
1291		else
1292			lfsr_value = calculate_lfsr(spu_cycle_reset);
1293
1294		/* must use a non zero value. Zero disables data collection. */
1295		if (lfsr_value == 0)
1296			lfsr_value = calculate_lfsr(1);
1297
1298		lfsr_value = lfsr_value << 8; /* shift lfsr to correct
1299						* register location
1300						*/
1301
1302		/* debug bus setup */
1303		ret = pm_rtas_activate_spu_profiling(cbe_cpu_to_node(cpu));
1304
1305		if (unlikely(ret)) {
1306			rtas_error = ret;
1307			goto out;
1308		}
1309
1310
1311		subfunc = 2;	/* 2 - activate SPU tracing, 3 - deactivate */
1312
1313		/* start profiling */
1314		ret = rtas_call(spu_rtas_token, 3, 1, NULL, subfunc,
1315				cbe_cpu_to_node(cpu), lfsr_value);
1316
1317		if (unlikely(ret != 0)) {
1318			printk(KERN_ERR
1319			       "%s: rtas call ibm,cbe-spu-perftools failed, " \
1320			       "return = %d\n", __func__, ret);
1321			rtas_error = -EIO;
1322			goto out;
1323		}
1324	}
1325
1326	rtas_error = start_spu_profiling_cycles(spu_cycle_reset);
1327	if (rtas_error)
1328		goto out_stop;
1329
1330	oprofile_running = 1;
1331	return 0;
1332
1333out_stop:
1334	cell_global_stop_spu_cycles();	/* clean up the PMU/debug bus */
1335out:
1336	return rtas_error;
1337}
1338
1339static int cell_global_start_spu_events(struct op_counter_config *ctr)
1340{
1341	int cpu;
1342	u32 interrupt_mask = 0;
1343	int rtn = 0;
1344
1345	hdw_thread = 0;
1346
1347	/* spu event profiling, uses the performance counters to generate
1348	 * an interrupt.  The hardware is setup to store the SPU program
1349	 * counter into the trace array.  The occurrence mode is used to
1350	 * enable storing data to the trace buffer.  The bits are set
1351	 * to send/store the SPU address in the trace buffer.  The debug
1352	 * bus must be setup to route the SPU program counter onto the
1353	 * debug bus.  The occurrence data in the trace buffer is not used.
1354	 */
1355
1356	/* This routine gets called once for the system.
1357	 * There is one performance monitor per node, so we
1358	 * only need to perform this function once per node.
1359	 */
1360
1361	for_each_online_cpu(cpu) {
1362		if (cbe_get_hw_thread_id(cpu))
1363			continue;
1364
1365		/*
1366		 * Setup SPU event-based profiling.
1367		 * Set perf_mon_control bit 0 to a zero before
1368		 * enabling spu collection hardware.
1369		 *
1370		 * Only support one SPU event on one SPU per node.
1371		 */
1372		if (ctr_enabled & 1) {
1373			cbe_write_ctr(cpu, 0, reset_value[0]);
1374			enable_ctr(cpu, 0, pm_regs.pm07_cntrl);
1375			interrupt_mask |=
1376				CBE_PM_CTR_OVERFLOW_INTR(0);
1377		} else {
1378			/* Disable counter */
1379			cbe_write_pm07_control(cpu, 0, 0);
1380		}
1381
1382		cbe_get_and_clear_pm_interrupts(cpu);
1383		cbe_enable_pm_interrupts(cpu, hdw_thread, interrupt_mask);
1384		cbe_enable_pm(cpu);
1385
1386		/* clear the trace buffer */
1387		cbe_write_pm(cpu, trace_address, 0);
1388	}
1389
1390	/* Start the timer to time slice collecting the event profile
1391	 * on each of the SPUs.  Note, can collect profile on one SPU
1392	 * per node at a time.
1393	 */
1394	start_spu_event_swap();
1395	start_spu_profiling_events();
1396	oprofile_running = 1;
1397	smp_wmb();
1398
1399	return rtn;
1400}
1401
1402static int cell_global_start_ppu(struct op_counter_config *ctr)
1403{
1404	u32 cpu, i;
1405	u32 interrupt_mask = 0;
1406
1407	/* This routine gets called once for the system.
1408	 * There is one performance monitor per node, so we
1409	 * only need to perform this function once per node.
1410	 */
1411	for_each_online_cpu(cpu) {
1412		if (cbe_get_hw_thread_id(cpu))
1413			continue;
1414
1415		interrupt_mask = 0;
1416
1417		for (i = 0; i < num_counters; ++i) {
1418			if (ctr_enabled & (1 << i)) {
1419				cbe_write_ctr(cpu, i, reset_value[i]);
1420				enable_ctr(cpu, i, pm_regs.pm07_cntrl);
1421				interrupt_mask |= CBE_PM_CTR_OVERFLOW_INTR(i);
1422			} else {
1423				/* Disable counter */
1424				cbe_write_pm07_control(cpu, i, 0);
1425			}
1426		}
1427
1428		cbe_get_and_clear_pm_interrupts(cpu);
1429		cbe_enable_pm_interrupts(cpu, hdw_thread, interrupt_mask);
1430		cbe_enable_pm(cpu);
1431	}
1432
1433	virt_cntr_inter_mask = interrupt_mask;
1434	oprofile_running = 1;
1435	smp_wmb();
1436
1437	/*
1438	 * NOTE: start_virt_cntrs will result in cell_virtual_cntr() being
1439	 * executed which manipulates the PMU.	We start the "virtual counter"
1440	 * here so that we do not need to synchronize access to the PMU in
1441	 * the above for-loop.
1442	 */
1443	start_virt_cntrs();
1444
1445	return 0;
1446}
1447
1448static int cell_global_start(struct op_counter_config *ctr)
1449{
1450	if (profiling_mode == SPU_PROFILING_CYCLES)
1451		return cell_global_start_spu_cycles(ctr);
1452	else if (profiling_mode == SPU_PROFILING_EVENTS)
1453		return cell_global_start_spu_events(ctr);
1454	else
1455		return cell_global_start_ppu(ctr);
1456}
1457
1458
1459/* The SPU interrupt handler
1460 *
1461 * SPU event profiling works as follows:
1462 * The pm_signal[0] holds the one SPU event to be measured.  It is routed on
1463 * the debug bus using word 0 or 1.  The value of pm_signal[1] and
1464 * pm_signal[2] contain the necessary events to route the SPU program
1465 * counter for the selected SPU onto the debug bus using words 2 and 3.
1466 * The pm_interval register is setup to write the SPU PC value into the
1467 * trace buffer at the maximum rate possible.  The trace buffer is configured
1468 * to store the PCs, wrapping when it is full.  The performance counter is
1469 * initialized to the max hardware count minus the number of events, N, between
1470 * samples.  Once the N events have occurred, a HW counter overflow occurs
1471 * causing the generation of a HW counter interrupt which also stops the
1472 * writing of the SPU PC values to the trace buffer.  Hence the last PC
1473 * written to the trace buffer is the SPU PC that we want.  Unfortunately,
1474 * we have to read from the beginning of the trace buffer to get to the
1475 * last value written.  We just hope the PPU has nothing better to do then
1476 * service this interrupt. The PC for the specific SPU being profiled is
1477 * extracted from the trace buffer processed and stored.  The trace buffer
1478 * is cleared, interrupts are cleared, the counter is reset to max - N.
1479 * A kernel timer is used to periodically call the routine spu_evnt_swap()
1480 * to switch to the next physical SPU in the node to profile in round robbin
1481 * order.  This way data is collected for all SPUs on the node. It does mean
1482 * that we need to use a relatively small value of N to ensure enough samples
1483 * on each SPU are collected each SPU is being profiled 1/8 of the time.
1484 * It may also be necessary to use a longer sample collection period.
1485 */
1486static void cell_handle_interrupt_spu(struct pt_regs *regs,
1487				      struct op_counter_config *ctr)
1488{
1489	u32 cpu, cpu_tmp;
1490	u64 trace_entry;
1491	u32 interrupt_mask;
1492	u64 trace_buffer[2];
1493	u64 last_trace_buffer;
1494	u32 sample;
1495	u32 trace_addr;
1496	unsigned long sample_array_lock_flags;
1497	int spu_num;
1498	unsigned long flags;
1499
1500	/* Make sure spu event interrupt handler and spu event swap
1501	 * don't access the counters simultaneously.
1502	 */
1503	cpu = smp_processor_id();
1504	spin_lock_irqsave(&cntr_lock, flags);
1505
1506	cpu_tmp = cpu;
1507	cbe_disable_pm(cpu);
1508
1509	interrupt_mask = cbe_get_and_clear_pm_interrupts(cpu);
1510
1511	sample = 0xABCDEF;
1512	trace_entry = 0xfedcba;
1513	last_trace_buffer = 0xdeadbeaf;
1514
1515	if ((oprofile_running == 1) && (interrupt_mask != 0)) {
1516		/* disable writes to trace buff */
1517		cbe_write_pm(cpu, pm_interval, 0);
1518
1519		/* only have one perf cntr being used, cntr 0 */
1520		if ((interrupt_mask & CBE_PM_CTR_OVERFLOW_INTR(0))
1521		    && ctr[0].enabled)
1522			/* The SPU PC values will be read
1523			 * from the trace buffer, reset counter
1524			 */
1525
1526			cbe_write_ctr(cpu, 0, reset_value[0]);
1527
1528		trace_addr = cbe_read_pm(cpu, trace_address);
1529
1530		while (!(trace_addr & CBE_PM_TRACE_BUF_EMPTY)) {
1531			/* There is data in the trace buffer to process
1532			 * Read the buffer until you get to the last
1533			 * entry.  This is the value we want.
1534			 */
1535
1536			cbe_read_trace_buffer(cpu, trace_buffer);
1537			trace_addr = cbe_read_pm(cpu, trace_address);
1538		}
1539
1540		/* SPU Address 16 bit count format for 128 bit
1541		 * HW trace buffer is used for the SPU PC storage
1542		 *    HDR bits          0:15
1543		 *    SPU Addr 0 bits   16:31
1544		 *    SPU Addr 1 bits   32:47
1545		 *    unused bits       48:127
1546		 *
1547		 * HDR: bit4 = 1 SPU Address 0 valid
1548		 * HDR: bit5 = 1 SPU Address 1 valid
1549		 *  - unfortunately, the valid bits don't seem to work
1550		 *
1551		 * Note trace_buffer[0] holds bits 0:63 of the HW
1552		 * trace buffer, trace_buffer[1] holds bits 64:127
1553		 */
1554
1555		trace_entry = trace_buffer[0]
1556			& 0x00000000FFFF0000;
1557
1558		/* only top 16 of the 18 bit SPU PC address
1559		 * is stored in trace buffer, hence shift right
1560		 * by 16 -2 bits */
1561		sample = trace_entry >> 14;
1562		last_trace_buffer = trace_buffer[0];
1563
1564		spu_num = spu_evnt_phys_spu_indx
1565			+ (cbe_cpu_to_node(cpu) * NUM_SPUS_PER_NODE);
1566
1567		/* make sure only one process at a time is calling
1568		 * spu_sync_buffer()
1569		 */
1570		spin_lock_irqsave(&oprof_spu_smpl_arry_lck,
1571				  sample_array_lock_flags);
1572		spu_sync_buffer(spu_num, &sample, 1);
1573		spin_unlock_irqrestore(&oprof_spu_smpl_arry_lck,
1574				       sample_array_lock_flags);
1575
1576		smp_wmb();    /* insure spu event buffer updates are written
1577			       * don't want events intermingled... */
1578
1579		/* The counters were frozen by the interrupt.
1580		 * Reenable the interrupt and restart the counters.
1581		 */
1582		cbe_write_pm(cpu, pm_interval, NUM_INTERVAL_CYC);
1583		cbe_enable_pm_interrupts(cpu, hdw_thread,
1584					 virt_cntr_inter_mask);
1585
1586		/* clear the trace buffer, re-enable writes to trace buff */
1587		cbe_write_pm(cpu, trace_address, 0);
1588		cbe_write_pm(cpu, pm_interval, NUM_INTERVAL_CYC);
1589
1590		/* The writes to the various performance counters only writes
1591		 * to a latch.  The new values (interrupt setting bits, reset
1592		 * counter value etc.) are not copied to the actual registers
1593		 * until the performance monitor is enabled.  In order to get
1594		 * this to work as desired, the performance monitor needs to
1595		 * be disabled while writing to the latches.  This is a
1596		 * HW design issue.
1597		 */
1598		write_pm_cntrl(cpu);
1599		cbe_enable_pm(cpu);
1600	}
1601	spin_unlock_irqrestore(&cntr_lock, flags);
1602}
1603
1604static void cell_handle_interrupt_ppu(struct pt_regs *regs,
1605				      struct op_counter_config *ctr)
1606{
1607	u32 cpu;
1608	u64 pc;
1609	int is_kernel;
1610	unsigned long flags = 0;
1611	u32 interrupt_mask;
1612	int i;
1613
1614	cpu = smp_processor_id();
1615
1616	/*
1617	 * Need to make sure the interrupt handler and the virt counter
1618	 * routine are not running at the same time. See the
1619	 * cell_virtual_cntr() routine for additional comments.
1620	 */
1621	spin_lock_irqsave(&cntr_lock, flags);
1622
1623	/*
1624	 * Need to disable and reenable the performance counters
1625	 * to get the desired behavior from the hardware.  This
1626	 * is hardware specific.
1627	 */
1628
1629	cbe_disable_pm(cpu);
1630
1631	interrupt_mask = cbe_get_and_clear_pm_interrupts(cpu);
1632
1633	/*
1634	 * If the interrupt mask has been cleared, then the virt cntr
1635	 * has cleared the interrupt.  When the thread that generated
1636	 * the interrupt is restored, the data count will be restored to
1637	 * 0xffffff0 to cause the interrupt to be regenerated.
1638	 */
1639
1640	if ((oprofile_running == 1) && (interrupt_mask != 0)) {
1641		pc = regs->nip;
1642		is_kernel = is_kernel_addr(pc);
1643
1644		for (i = 0; i < num_counters; ++i) {
1645			if ((interrupt_mask & CBE_PM_CTR_OVERFLOW_INTR(i))
1646			    && ctr[i].enabled) {
1647				oprofile_add_ext_sample(pc, regs, i, is_kernel);
1648				cbe_write_ctr(cpu, i, reset_value[i]);
1649			}
1650		}
1651
1652		/*
1653		 * The counters were frozen by the interrupt.
1654		 * Reenable the interrupt and restart the counters.
1655		 * If there was a race between the interrupt handler and
1656		 * the virtual counter routine.	 The virtual counter
1657		 * routine may have cleared the interrupts.  Hence must
1658		 * use the virt_cntr_inter_mask to re-enable the interrupts.
1659		 */
1660		cbe_enable_pm_interrupts(cpu, hdw_thread,
1661					 virt_cntr_inter_mask);
1662
1663		/*
1664		 * The writes to the various performance counters only writes
1665		 * to a latch.	The new values (interrupt setting bits, reset
1666		 * counter value etc.) are not copied to the actual registers
1667		 * until the performance monitor is enabled.  In order to get
1668		 * this to work as desired, the performance monitor needs to
1669		 * be disabled while writing to the latches.  This is a
1670		 * HW design issue.
1671		 */
1672		cbe_enable_pm(cpu);
1673	}
1674	spin_unlock_irqrestore(&cntr_lock, flags);
1675}
1676
1677static void cell_handle_interrupt(struct pt_regs *regs,
1678				  struct op_counter_config *ctr)
1679{
1680	if (profiling_mode == PPU_PROFILING)
1681		cell_handle_interrupt_ppu(regs, ctr);
1682	else
1683		cell_handle_interrupt_spu(regs, ctr);
1684}
1685
1686/*
1687 * This function is called from the generic OProfile
1688 * driver.  When profiling PPUs, we need to do the
1689 * generic sync start; otherwise, do spu_sync_start.
1690 */
1691static int cell_sync_start(void)
1692{
1693	if ((profiling_mode == SPU_PROFILING_CYCLES) ||
1694	    (profiling_mode == SPU_PROFILING_EVENTS))
1695		return spu_sync_start();
1696	else
1697		return DO_GENERIC_SYNC;
1698}
1699
1700static int cell_sync_stop(void)
1701{
1702	if ((profiling_mode == SPU_PROFILING_CYCLES) ||
1703	    (profiling_mode == SPU_PROFILING_EVENTS))
1704		return spu_sync_stop();
1705	else
1706		return 1;
1707}
1708
1709struct op_powerpc_model op_model_cell = {
1710	.reg_setup = cell_reg_setup,
1711	.cpu_setup = cell_cpu_setup,
1712	.global_start = cell_global_start,
1713	.global_stop = cell_global_stop,
1714	.sync_start = cell_sync_start,
1715	.sync_stop = cell_sync_stop,
1716	.handle_interrupt = cell_handle_interrupt,
1717};
1718