1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Cell Broadband Engine OProfile Support
4 *
5 * (C) Copyright IBM Corporation 2006
6 *
7 * Author: David Erb (djerb@us.ibm.com)
8 * Modifications:
9 *	   Carl Love <carll@us.ibm.com>
10 *	   Maynard Johnson <maynardj@us.ibm.com>
11 */
12
13#include <linux/cpufreq.h>
14#include <linux/delay.h>
15#include <linux/jiffies.h>
16#include <linux/kthread.h>
17#include <linux/oprofile.h>
18#include <linux/percpu.h>
19#include <linux/smp.h>
20#include <linux/spinlock.h>
21#include <linux/timer.h>
22#include <asm/cell-pmu.h>
23#include <asm/cputable.h>
24#include <asm/firmware.h>
25#include <asm/io.h>
26#include <asm/oprofile_impl.h>
27#include <asm/processor.h>
28#include <asm/prom.h>
29#include <asm/ptrace.h>
30#include <asm/reg.h>
31#include <asm/rtas.h>
32#include <asm/cell-regs.h>
33
34#include "../platforms/cell/interrupt.h"
35#include "cell/pr_util.h"
36
37#define PPU_PROFILING            0
38#define SPU_PROFILING_CYCLES     1
39#define SPU_PROFILING_EVENTS     2
40
41#define SPU_EVENT_NUM_START      4100
42#define SPU_EVENT_NUM_STOP       4399
43#define SPU_PROFILE_EVENT_ADDR          4363  /* spu, address trace, decimal */
44#define SPU_PROFILE_EVENT_ADDR_MASK_A   0x146 /* sub unit set to zero */
45#define SPU_PROFILE_EVENT_ADDR_MASK_B   0x186 /* sub unit set to zero */
46
47#define NUM_SPUS_PER_NODE    8
48#define SPU_CYCLES_EVENT_NUM 2	/*  event number for SPU_CYCLES */
49
50#define PPU_CYCLES_EVENT_NUM 1	/*  event number for CYCLES */
51#define PPU_CYCLES_GRP_NUM   1	/* special group number for identifying
52				 * PPU_CYCLES event
53				 */
54#define CBE_COUNT_ALL_CYCLES 0x42800000 /* PPU cycle event specifier */
55
56#define NUM_THREADS 2         /* number of physical threads in
57			       * physical processor
58			       */
59#define NUM_DEBUG_BUS_WORDS 4
60#define NUM_INPUT_BUS_WORDS 2
61
62#define MAX_SPU_COUNT 0xFFFFFF	/* maximum 24 bit LFSR value */
63
64/* Minimum HW interval timer setting to send value to trace buffer is 10 cycle.
65 * To configure counter to send value every N cycles set counter to
66 * 2^32 - 1 - N.
67 */
68#define NUM_INTERVAL_CYC  0xFFFFFFFF - 10
69
70/*
71 * spu_cycle_reset is the number of cycles between samples.
72 * This variable is used for SPU profiling and should ONLY be set
73 * at the beginning of cell_reg_setup; otherwise, it's read-only.
74 */
75static unsigned int spu_cycle_reset;
76static unsigned int profiling_mode;
77static int spu_evnt_phys_spu_indx;
78
79struct pmc_cntrl_data {
80	unsigned long vcntr;
81	unsigned long evnts;
82	unsigned long masks;
83	unsigned long enabled;
84};
85
86/*
87 * ibm,cbe-perftools rtas parameters
88 */
89struct pm_signal {
90	u16 cpu;		/* Processor to modify */
91	u16 sub_unit;		/* hw subunit this applies to (if applicable)*/
92	short int signal_group; /* Signal Group to Enable/Disable */
93	u8 bus_word;		/* Enable/Disable on this Trace/Trigger/Event
94				 * Bus Word(s) (bitmask)
95				 */
96	u8 bit;			/* Trigger/Event bit (if applicable) */
97};
98
99/*
100 * rtas call arguments
101 */
102enum {
103	SUBFUNC_RESET = 1,
104	SUBFUNC_ACTIVATE = 2,
105	SUBFUNC_DEACTIVATE = 3,
106
107	PASSTHRU_IGNORE = 0,
108	PASSTHRU_ENABLE = 1,
109	PASSTHRU_DISABLE = 2,
110};
111
112struct pm_cntrl {
113	u16 enable;
114	u16 stop_at_max;
115	u16 trace_mode;
116	u16 freeze;
117	u16 count_mode;
118	u16 spu_addr_trace;
119	u8  trace_buf_ovflw;
120};
121
122static struct {
123	u32 group_control;
124	u32 debug_bus_control;
125	struct pm_cntrl pm_cntrl;
126	u32 pm07_cntrl[NR_PHYS_CTRS];
127} pm_regs;
128
129#define GET_SUB_UNIT(x) ((x & 0x0000f000) >> 12)
130#define GET_BUS_WORD(x) ((x & 0x000000f0) >> 4)
131#define GET_BUS_TYPE(x) ((x & 0x00000300) >> 8)
132#define GET_POLARITY(x) ((x & 0x00000002) >> 1)
133#define GET_COUNT_CYCLES(x) (x & 0x00000001)
134#define GET_INPUT_CONTROL(x) ((x & 0x00000004) >> 2)
135
136static DEFINE_PER_CPU(unsigned long[NR_PHYS_CTRS], pmc_values);
137static unsigned long spu_pm_cnt[MAX_NUMNODES * NUM_SPUS_PER_NODE];
138static struct pmc_cntrl_data pmc_cntrl[NUM_THREADS][NR_PHYS_CTRS];
139
140/*
141 * The CELL profiling code makes rtas calls to setup the debug bus to
142 * route the performance signals.  Additionally, SPU profiling requires
143 * a second rtas call to setup the hardware to capture the SPU PCs.
144 * The EIO error value is returned if the token lookups or the rtas
145 * call fail.  The EIO error number is the best choice of the existing
146 * error numbers.  The probability of rtas related error is very low.  But
147 * by returning EIO and printing additional information to dmsg the user
148 * will know that OProfile did not start and dmesg will tell them why.
149 * OProfile does not support returning errors on Stop.	Not a huge issue
150 * since failure to reset the debug bus or stop the SPU PC collection is
151 * not a fatel issue.  Chances are if the Stop failed, Start doesn't work
152 * either.
153 */
154
155/*
156 * Interpetation of hdw_thread:
157 * 0 - even virtual cpus 0, 2, 4,...
158 * 1 - odd virtual cpus 1, 3, 5, ...
159 *
160 * FIXME: this is strictly wrong, we need to clean this up in a number
161 * of places. It works for now. -arnd
162 */
163static u32 hdw_thread;
164
165static u32 virt_cntr_inter_mask;
166static struct timer_list timer_virt_cntr;
167static struct timer_list timer_spu_event_swap;
168
169/*
170 * pm_signal needs to be global since it is initialized in
171 * cell_reg_setup at the time when the necessary information
172 * is available.
173 */
174static struct pm_signal pm_signal[NR_PHYS_CTRS];
175static int pm_rtas_token;    /* token for debug bus setup call */
176static int spu_rtas_token;   /* token for SPU cycle profiling */
177
178static u32 reset_value[NR_PHYS_CTRS];
179static int num_counters;
180static int oprofile_running;
181static DEFINE_SPINLOCK(cntr_lock);
182
183static u32 ctr_enabled;
184
185static unsigned char input_bus[NUM_INPUT_BUS_WORDS];
186
187/*
188 * Firmware interface functions
189 */
190static int
191rtas_ibm_cbe_perftools(int subfunc, int passthru,
192		       void *address, unsigned long length)
193{
194	u64 paddr = __pa(address);
195
196	return rtas_call(pm_rtas_token, 5, 1, NULL, subfunc,
197			 passthru, paddr >> 32, paddr & 0xffffffff, length);
198}
199
200static void pm_rtas_reset_signals(u32 node)
201{
202	int ret;
203	struct pm_signal pm_signal_local;
204
205	/*
206	 * The debug bus is being set to the passthru disable state.
207	 * However, the FW still expects at least one legal signal routing
208	 * entry or it will return an error on the arguments.	If we don't
209	 * supply a valid entry, we must ignore all return values.  Ignoring
210	 * all return values means we might miss an error we should be
211	 * concerned about.
212	 */
213
214	/*  fw expects physical cpu #. */
215	pm_signal_local.cpu = node;
216	pm_signal_local.signal_group = 21;
217	pm_signal_local.bus_word = 1;
218	pm_signal_local.sub_unit = 0;
219	pm_signal_local.bit = 0;
220
221	ret = rtas_ibm_cbe_perftools(SUBFUNC_RESET, PASSTHRU_DISABLE,
222				     &pm_signal_local,
223				     sizeof(struct pm_signal));
224
225	if (unlikely(ret))
226		/*
227		 * Not a fatal error. For Oprofile stop, the oprofile
228		 * functions do not support returning an error for
229		 * failure to stop OProfile.
230		 */
231		printk(KERN_WARNING "%s: rtas returned: %d\n",
232		       __func__, ret);
233}
234
235static int pm_rtas_activate_signals(u32 node, u32 count)
236{
237	int ret;
238	int i, j;
239	struct pm_signal pm_signal_local[NR_PHYS_CTRS];
240
241	/*
242	 * There is no debug setup required for the cycles event.
243	 * Note that only events in the same group can be used.
244	 * Otherwise, there will be conflicts in correctly routing
245	 * the signals on the debug bus.  It is the responsibility
246	 * of the OProfile user tool to check the events are in
247	 * the same group.
248	 */
249	i = 0;
250	for (j = 0; j < count; j++) {
251		if (pm_signal[j].signal_group != PPU_CYCLES_GRP_NUM) {
252
253			/* fw expects physical cpu # */
254			pm_signal_local[i].cpu = node;
255			pm_signal_local[i].signal_group
256				= pm_signal[j].signal_group;
257			pm_signal_local[i].bus_word = pm_signal[j].bus_word;
258			pm_signal_local[i].sub_unit = pm_signal[j].sub_unit;
259			pm_signal_local[i].bit = pm_signal[j].bit;
260			i++;
261		}
262	}
263
264	if (i != 0) {
265		ret = rtas_ibm_cbe_perftools(SUBFUNC_ACTIVATE, PASSTHRU_ENABLE,
266					     pm_signal_local,
267					     i * sizeof(struct pm_signal));
268
269		if (unlikely(ret)) {
270			printk(KERN_WARNING "%s: rtas returned: %d\n",
271			       __func__, ret);
272			return -EIO;
273		}
274	}
275
276	return 0;
277}
278
279/*
280 * PM Signal functions
281 */
282static void set_pm_event(u32 ctr, int event, u32 unit_mask)
283{
284	struct pm_signal *p;
285	u32 signal_bit;
286	u32 bus_word, bus_type, count_cycles, polarity, input_control;
287	int j, i;
288
289	if (event == PPU_CYCLES_EVENT_NUM) {
290		/* Special Event: Count all cpu cycles */
291		pm_regs.pm07_cntrl[ctr] = CBE_COUNT_ALL_CYCLES;
292		p = &(pm_signal[ctr]);
293		p->signal_group = PPU_CYCLES_GRP_NUM;
294		p->bus_word = 1;
295		p->sub_unit = 0;
296		p->bit = 0;
297		goto out;
298	} else {
299		pm_regs.pm07_cntrl[ctr] = 0;
300	}
301
302	bus_word = GET_BUS_WORD(unit_mask);
303	bus_type = GET_BUS_TYPE(unit_mask);
304	count_cycles = GET_COUNT_CYCLES(unit_mask);
305	polarity = GET_POLARITY(unit_mask);
306	input_control = GET_INPUT_CONTROL(unit_mask);
307	signal_bit = (event % 100);
308
309	p = &(pm_signal[ctr]);
310
311	p->signal_group = event / 100;
312	p->bus_word = bus_word;
313	p->sub_unit = GET_SUB_UNIT(unit_mask);
314
315	pm_regs.pm07_cntrl[ctr] = 0;
316	pm_regs.pm07_cntrl[ctr] |= PM07_CTR_COUNT_CYCLES(count_cycles);
317	pm_regs.pm07_cntrl[ctr] |= PM07_CTR_POLARITY(polarity);
318	pm_regs.pm07_cntrl[ctr] |= PM07_CTR_INPUT_CONTROL(input_control);
319
320	/*
321	 * Some of the islands signal selection is based on 64 bit words.
322	 * The debug bus words are 32 bits, the input words to the performance
323	 * counters are defined as 32 bits.  Need to convert the 64 bit island
324	 * specification to the appropriate 32 input bit and bus word for the
325	 * performance counter event selection.	 See the CELL Performance
326	 * monitoring signals manual and the Perf cntr hardware descriptions
327	 * for the details.
328	 */
329	if (input_control == 0) {
330		if (signal_bit > 31) {
331			signal_bit -= 32;
332			if (bus_word == 0x3)
333				bus_word = 0x2;
334			else if (bus_word == 0xc)
335				bus_word = 0x8;
336		}
337
338		if ((bus_type == 0) && p->signal_group >= 60)
339			bus_type = 2;
340		if ((bus_type == 1) && p->signal_group >= 50)
341			bus_type = 0;
342
343		pm_regs.pm07_cntrl[ctr] |= PM07_CTR_INPUT_MUX(signal_bit);
344	} else {
345		pm_regs.pm07_cntrl[ctr] = 0;
346		p->bit = signal_bit;
347	}
348
349	for (i = 0; i < NUM_DEBUG_BUS_WORDS; i++) {
350		if (bus_word & (1 << i)) {
351			pm_regs.debug_bus_control |=
352				(bus_type << (30 - (2 * i)));
353
354			for (j = 0; j < NUM_INPUT_BUS_WORDS; j++) {
355				if (input_bus[j] == 0xff) {
356					input_bus[j] = i;
357					pm_regs.group_control |=
358						(i << (30 - (2 * j)));
359
360					break;
361				}
362			}
363		}
364	}
365out:
366	;
367}
368
369static void write_pm_cntrl(int cpu)
370{
371	/*
372	 * Oprofile will use 32 bit counters, set bits 7:10 to 0
373	 * pmregs.pm_cntrl is a global
374	 */
375
376	u32 val = 0;
377	if (pm_regs.pm_cntrl.enable == 1)
378		val |= CBE_PM_ENABLE_PERF_MON;
379
380	if (pm_regs.pm_cntrl.stop_at_max == 1)
381		val |= CBE_PM_STOP_AT_MAX;
382
383	if (pm_regs.pm_cntrl.trace_mode != 0)
384		val |= CBE_PM_TRACE_MODE_SET(pm_regs.pm_cntrl.trace_mode);
385
386	if (pm_regs.pm_cntrl.trace_buf_ovflw == 1)
387		val |= CBE_PM_TRACE_BUF_OVFLW(pm_regs.pm_cntrl.trace_buf_ovflw);
388	if (pm_regs.pm_cntrl.freeze == 1)
389		val |= CBE_PM_FREEZE_ALL_CTRS;
390
391	val |= CBE_PM_SPU_ADDR_TRACE_SET(pm_regs.pm_cntrl.spu_addr_trace);
392
393	/*
394	 * Routine set_count_mode must be called previously to set
395	 * the count mode based on the user selection of user and kernel.
396	 */
397	val |= CBE_PM_COUNT_MODE_SET(pm_regs.pm_cntrl.count_mode);
398	cbe_write_pm(cpu, pm_control, val);
399}
400
401static inline void
402set_count_mode(u32 kernel, u32 user)
403{
404	/*
405	 * The user must specify user and kernel if they want them. If
406	 *  neither is specified, OProfile will count in hypervisor mode.
407	 *  pm_regs.pm_cntrl is a global
408	 */
409	if (kernel) {
410		if (user)
411			pm_regs.pm_cntrl.count_mode = CBE_COUNT_ALL_MODES;
412		else
413			pm_regs.pm_cntrl.count_mode =
414				CBE_COUNT_SUPERVISOR_MODE;
415	} else {
416		if (user)
417			pm_regs.pm_cntrl.count_mode = CBE_COUNT_PROBLEM_MODE;
418		else
419			pm_regs.pm_cntrl.count_mode =
420				CBE_COUNT_HYPERVISOR_MODE;
421	}
422}
423
424static inline void enable_ctr(u32 cpu, u32 ctr, u32 *pm07_cntrl)
425{
426
427	pm07_cntrl[ctr] |= CBE_PM_CTR_ENABLE;
428	cbe_write_pm07_control(cpu, ctr, pm07_cntrl[ctr]);
429}
430
431/*
432 * Oprofile is expected to collect data on all CPUs simultaneously.
433 * However, there is one set of performance counters per node.	There are
434 * two hardware threads or virtual CPUs on each node.  Hence, OProfile must
435 * multiplex in time the performance counter collection on the two virtual
436 * CPUs.  The multiplexing of the performance counters is done by this
437 * virtual counter routine.
438 *
439 * The pmc_values used below is defined as 'per-cpu' but its use is
440 * more akin to 'per-node'.  We need to store two sets of counter
441 * values per node -- one for the previous run and one for the next.
442 * The per-cpu[NR_PHYS_CTRS] gives us the storage we need.  Each odd/even
443 * pair of per-cpu arrays is used for storing the previous and next
444 * pmc values for a given node.
445 * NOTE: We use the per-cpu variable to improve cache performance.
446 *
447 * This routine will alternate loading the virtual counters for
448 * virtual CPUs
449 */
450static void cell_virtual_cntr(struct timer_list *unused)
451{
452	int i, prev_hdw_thread, next_hdw_thread;
453	u32 cpu;
454	unsigned long flags;
455
456	/*
457	 * Make sure that the interrupt_hander and the virt counter are
458	 * not both playing with the counters on the same node.
459	 */
460
461	spin_lock_irqsave(&cntr_lock, flags);
462
463	prev_hdw_thread = hdw_thread;
464
465	/* switch the cpu handling the interrupts */
466	hdw_thread = 1 ^ hdw_thread;
467	next_hdw_thread = hdw_thread;
468
469	pm_regs.group_control = 0;
470	pm_regs.debug_bus_control = 0;
471
472	for (i = 0; i < NUM_INPUT_BUS_WORDS; i++)
473		input_bus[i] = 0xff;
474
475	/*
476	 * There are some per thread events.  Must do the
477	 * set event, for the thread that is being started
478	 */
479	for (i = 0; i < num_counters; i++)
480		set_pm_event(i,
481			pmc_cntrl[next_hdw_thread][i].evnts,
482			pmc_cntrl[next_hdw_thread][i].masks);
483
484	/*
485	 * The following is done only once per each node, but
486	 * we need cpu #, not node #, to pass to the cbe_xxx functions.
487	 */
488	for_each_online_cpu(cpu) {
489		if (cbe_get_hw_thread_id(cpu))
490			continue;
491
492		/*
493		 * stop counters, save counter values, restore counts
494		 * for previous thread
495		 */
496		cbe_disable_pm(cpu);
497		cbe_disable_pm_interrupts(cpu);
498		for (i = 0; i < num_counters; i++) {
499			per_cpu(pmc_values, cpu + prev_hdw_thread)[i]
500				= cbe_read_ctr(cpu, i);
501
502			if (per_cpu(pmc_values, cpu + next_hdw_thread)[i]
503			    == 0xFFFFFFFF)
504				/* If the cntr value is 0xffffffff, we must
505				 * reset that to 0xfffffff0 when the current
506				 * thread is restarted.	 This will generate a
507				 * new interrupt and make sure that we never
508				 * restore the counters to the max value.  If
509				 * the counters were restored to the max value,
510				 * they do not increment and no interrupts are
511				 * generated.  Hence no more samples will be
512				 * collected on that cpu.
513				 */
514				cbe_write_ctr(cpu, i, 0xFFFFFFF0);
515			else
516				cbe_write_ctr(cpu, i,
517					      per_cpu(pmc_values,
518						      cpu +
519						      next_hdw_thread)[i]);
520		}
521
522		/*
523		 * Switch to the other thread. Change the interrupt
524		 * and control regs to be scheduled on the CPU
525		 * corresponding to the thread to execute.
526		 */
527		for (i = 0; i < num_counters; i++) {
528			if (pmc_cntrl[next_hdw_thread][i].enabled) {
529				/*
530				 * There are some per thread events.
531				 * Must do the set event, enable_cntr
532				 * for each cpu.
533				 */
534				enable_ctr(cpu, i,
535					   pm_regs.pm07_cntrl);
536			} else {
537				cbe_write_pm07_control(cpu, i, 0);
538			}
539		}
540
541		/* Enable interrupts on the CPU thread that is starting */
542		cbe_enable_pm_interrupts(cpu, next_hdw_thread,
543					 virt_cntr_inter_mask);
544		cbe_enable_pm(cpu);
545	}
546
547	spin_unlock_irqrestore(&cntr_lock, flags);
548
549	mod_timer(&timer_virt_cntr, jiffies + HZ / 10);
550}
551
552static void start_virt_cntrs(void)
553{
554	timer_setup(&timer_virt_cntr, cell_virtual_cntr, 0);
555	timer_virt_cntr.expires = jiffies + HZ / 10;
556	add_timer(&timer_virt_cntr);
557}
558
559static int cell_reg_setup_spu_cycles(struct op_counter_config *ctr,
560			struct op_system_config *sys, int num_ctrs)
561{
562	spu_cycle_reset = ctr[0].count;
563
564	/*
565	 * Each node will need to make the rtas call to start
566	 * and stop SPU profiling.  Get the token once and store it.
567	 */
568	spu_rtas_token = rtas_token("ibm,cbe-spu-perftools");
569
570	if (unlikely(spu_rtas_token == RTAS_UNKNOWN_SERVICE)) {
571		printk(KERN_ERR
572		       "%s: rtas token ibm,cbe-spu-perftools unknown\n",
573		       __func__);
574		return -EIO;
575	}
576	return 0;
577}
578
579/* Unfortunately, the hardware will only support event profiling
580 * on one SPU per node at a time.  Therefore, we must time slice
581 * the profiling across all SPUs in the node.  Note, we do this
582 * in parallel for each node.  The following routine is called
583 * periodically based on kernel timer to switch which SPU is
584 * being monitored in a round robbin fashion.
585 */
586static void spu_evnt_swap(struct timer_list *unused)
587{
588	int node;
589	int cur_phys_spu, nxt_phys_spu, cur_spu_evnt_phys_spu_indx;
590	unsigned long flags;
591	int cpu;
592	int ret;
593	u32 interrupt_mask;
594
595
596	/* enable interrupts on cntr 0 */
597	interrupt_mask = CBE_PM_CTR_OVERFLOW_INTR(0);
598
599	hdw_thread = 0;
600
601	/* Make sure spu event interrupt handler and spu event swap
602	 * don't access the counters simultaneously.
603	 */
604	spin_lock_irqsave(&cntr_lock, flags);
605
606	cur_spu_evnt_phys_spu_indx = spu_evnt_phys_spu_indx;
607
608	if (++(spu_evnt_phys_spu_indx) == NUM_SPUS_PER_NODE)
609		spu_evnt_phys_spu_indx = 0;
610
611	pm_signal[0].sub_unit = spu_evnt_phys_spu_indx;
612	pm_signal[1].sub_unit = spu_evnt_phys_spu_indx;
613	pm_signal[2].sub_unit = spu_evnt_phys_spu_indx;
614
615	/* switch the SPU being profiled on each node */
616	for_each_online_cpu(cpu) {
617		if (cbe_get_hw_thread_id(cpu))
618			continue;
619
620		node = cbe_cpu_to_node(cpu);
621		cur_phys_spu = (node * NUM_SPUS_PER_NODE)
622			+ cur_spu_evnt_phys_spu_indx;
623		nxt_phys_spu = (node * NUM_SPUS_PER_NODE)
624			+ spu_evnt_phys_spu_indx;
625
626		/*
627		 * stop counters, save counter values, restore counts
628		 * for previous physical SPU
629		 */
630		cbe_disable_pm(cpu);
631		cbe_disable_pm_interrupts(cpu);
632
633		spu_pm_cnt[cur_phys_spu]
634			= cbe_read_ctr(cpu, 0);
635
636		/* restore previous count for the next spu to sample */
637		/* NOTE, hardware issue, counter will not start if the
638		 * counter value is at max (0xFFFFFFFF).
639		 */
640		if (spu_pm_cnt[nxt_phys_spu] >= 0xFFFFFFFF)
641			cbe_write_ctr(cpu, 0, 0xFFFFFFF0);
642		 else
643			 cbe_write_ctr(cpu, 0, spu_pm_cnt[nxt_phys_spu]);
644
645		pm_rtas_reset_signals(cbe_cpu_to_node(cpu));
646
647		/* setup the debug bus measure the one event and
648		 * the two events to route the next SPU's PC on
649		 * the debug bus
650		 */
651		ret = pm_rtas_activate_signals(cbe_cpu_to_node(cpu), 3);
652		if (ret)
653			printk(KERN_ERR "%s: pm_rtas_activate_signals failed, "
654			       "SPU event swap\n", __func__);
655
656		/* clear the trace buffer, don't want to take PC for
657		 * previous SPU*/
658		cbe_write_pm(cpu, trace_address, 0);
659
660		enable_ctr(cpu, 0, pm_regs.pm07_cntrl);
661
662		/* Enable interrupts on the CPU thread that is starting */
663		cbe_enable_pm_interrupts(cpu, hdw_thread,
664					 interrupt_mask);
665		cbe_enable_pm(cpu);
666	}
667
668	spin_unlock_irqrestore(&cntr_lock, flags);
669
670	/* swap approximately every 0.1 seconds */
671	mod_timer(&timer_spu_event_swap, jiffies + HZ / 25);
672}
673
674static void start_spu_event_swap(void)
675{
676	timer_setup(&timer_spu_event_swap, spu_evnt_swap, 0);
677	timer_spu_event_swap.expires = jiffies + HZ / 25;
678	add_timer(&timer_spu_event_swap);
679}
680
681static int cell_reg_setup_spu_events(struct op_counter_config *ctr,
682			struct op_system_config *sys, int num_ctrs)
683{
684	int i;
685
686	/* routine is called once for all nodes */
687
688	spu_evnt_phys_spu_indx = 0;
689	/*
690	 * For all events except PPU CYCLEs, each node will need to make
691	 * the rtas cbe-perftools call to setup and reset the debug bus.
692	 * Make the token lookup call once and store it in the global
693	 * variable pm_rtas_token.
694	 */
695	pm_rtas_token = rtas_token("ibm,cbe-perftools");
696
697	if (unlikely(pm_rtas_token == RTAS_UNKNOWN_SERVICE)) {
698		printk(KERN_ERR
699		       "%s: rtas token ibm,cbe-perftools unknown\n",
700		       __func__);
701		return -EIO;
702	}
703
704	/* setup the pm_control register settings,
705	 * settings will be written per node by the
706	 * cell_cpu_setup() function.
707	 */
708	pm_regs.pm_cntrl.trace_buf_ovflw = 1;
709
710	/* Use the occurrence trace mode to have SPU PC saved
711	 * to the trace buffer.  Occurrence data in trace buffer
712	 * is not used.  Bit 2 must be set to store SPU addresses.
713	 */
714	pm_regs.pm_cntrl.trace_mode = 2;
715
716	pm_regs.pm_cntrl.spu_addr_trace = 0x1;  /* using debug bus
717						   event 2 & 3 */
718
719	/* setup the debug bus event array with the SPU PC routing events.
720	*  Note, pm_signal[0] will be filled in by set_pm_event() call below.
721	*/
722	pm_signal[1].signal_group = SPU_PROFILE_EVENT_ADDR / 100;
723	pm_signal[1].bus_word = GET_BUS_WORD(SPU_PROFILE_EVENT_ADDR_MASK_A);
724	pm_signal[1].bit = SPU_PROFILE_EVENT_ADDR % 100;
725	pm_signal[1].sub_unit = spu_evnt_phys_spu_indx;
726
727	pm_signal[2].signal_group = SPU_PROFILE_EVENT_ADDR / 100;
728	pm_signal[2].bus_word = GET_BUS_WORD(SPU_PROFILE_EVENT_ADDR_MASK_B);
729	pm_signal[2].bit = SPU_PROFILE_EVENT_ADDR % 100;
730	pm_signal[2].sub_unit = spu_evnt_phys_spu_indx;
731
732	/* Set the user selected spu event to profile on,
733	 * note, only one SPU profiling event is supported
734	 */
735	num_counters = 1;  /* Only support one SPU event at a time */
736	set_pm_event(0, ctr[0].event, ctr[0].unit_mask);
737
738	reset_value[0] = 0xFFFFFFFF - ctr[0].count;
739
740	/* global, used by cell_cpu_setup */
741	ctr_enabled |= 1;
742
743	/* Initialize the count for each SPU to the reset value */
744	for (i=0; i < MAX_NUMNODES * NUM_SPUS_PER_NODE; i++)
745		spu_pm_cnt[i] = reset_value[0];
746
747	return 0;
748}
749
750static int cell_reg_setup_ppu(struct op_counter_config *ctr,
751			struct op_system_config *sys, int num_ctrs)
752{
753	/* routine is called once for all nodes */
754	int i, j, cpu;
755
756	num_counters = num_ctrs;
757
758	if (unlikely(num_ctrs > NR_PHYS_CTRS)) {
759		printk(KERN_ERR
760		       "%s: Oprofile, number of specified events " \
761		       "exceeds number of physical counters\n",
762		       __func__);
763		return -EIO;
764	}
765
766	set_count_mode(sys->enable_kernel, sys->enable_user);
767
768	/* Setup the thread 0 events */
769	for (i = 0; i < num_ctrs; ++i) {
770
771		pmc_cntrl[0][i].evnts = ctr[i].event;
772		pmc_cntrl[0][i].masks = ctr[i].unit_mask;
773		pmc_cntrl[0][i].enabled = ctr[i].enabled;
774		pmc_cntrl[0][i].vcntr = i;
775
776		for_each_possible_cpu(j)
777			per_cpu(pmc_values, j)[i] = 0;
778	}
779
780	/*
781	 * Setup the thread 1 events, map the thread 0 event to the
782	 * equivalent thread 1 event.
783	 */
784	for (i = 0; i < num_ctrs; ++i) {
785		if ((ctr[i].event >= 2100) && (ctr[i].event <= 2111))
786			pmc_cntrl[1][i].evnts = ctr[i].event + 19;
787		else if (ctr[i].event == 2203)
788			pmc_cntrl[1][i].evnts = ctr[i].event;
789		else if ((ctr[i].event >= 2200) && (ctr[i].event <= 2215))
790			pmc_cntrl[1][i].evnts = ctr[i].event + 16;
791		else
792			pmc_cntrl[1][i].evnts = ctr[i].event;
793
794		pmc_cntrl[1][i].masks = ctr[i].unit_mask;
795		pmc_cntrl[1][i].enabled = ctr[i].enabled;
796		pmc_cntrl[1][i].vcntr = i;
797	}
798
799	for (i = 0; i < NUM_INPUT_BUS_WORDS; i++)
800		input_bus[i] = 0xff;
801
802	/*
803	 * Our counters count up, and "count" refers to
804	 * how much before the next interrupt, and we interrupt
805	 * on overflow.	 So we calculate the starting value
806	 * which will give us "count" until overflow.
807	 * Then we set the events on the enabled counters.
808	 */
809	for (i = 0; i < num_counters; ++i) {
810		/* start with virtual counter set 0 */
811		if (pmc_cntrl[0][i].enabled) {
812			/* Using 32bit counters, reset max - count */
813			reset_value[i] = 0xFFFFFFFF - ctr[i].count;
814			set_pm_event(i,
815				     pmc_cntrl[0][i].evnts,
816				     pmc_cntrl[0][i].masks);
817
818			/* global, used by cell_cpu_setup */
819			ctr_enabled |= (1 << i);
820		}
821	}
822
823	/* initialize the previous counts for the virtual cntrs */
824	for_each_online_cpu(cpu)
825		for (i = 0; i < num_counters; ++i) {
826			per_cpu(pmc_values, cpu)[i] = reset_value[i];
827		}
828
829	return 0;
830}
831
832
833/* This function is called once for all cpus combined */
834static int cell_reg_setup(struct op_counter_config *ctr,
835			struct op_system_config *sys, int num_ctrs)
836{
837	int ret=0;
838	spu_cycle_reset = 0;
839
840	/* initialize the spu_arr_trace value, will be reset if
841	 * doing spu event profiling.
842	 */
843	pm_regs.group_control = 0;
844	pm_regs.debug_bus_control = 0;
845	pm_regs.pm_cntrl.stop_at_max = 1;
846	pm_regs.pm_cntrl.trace_mode = 0;
847	pm_regs.pm_cntrl.freeze = 1;
848	pm_regs.pm_cntrl.trace_buf_ovflw = 0;
849	pm_regs.pm_cntrl.spu_addr_trace = 0;
850
851	/*
852	 * For all events except PPU CYCLEs, each node will need to make
853	 * the rtas cbe-perftools call to setup and reset the debug bus.
854	 * Make the token lookup call once and store it in the global
855	 * variable pm_rtas_token.
856	 */
857	pm_rtas_token = rtas_token("ibm,cbe-perftools");
858
859	if (unlikely(pm_rtas_token == RTAS_UNKNOWN_SERVICE)) {
860		printk(KERN_ERR
861		       "%s: rtas token ibm,cbe-perftools unknown\n",
862		       __func__);
863		return -EIO;
864	}
865
866	if (ctr[0].event == SPU_CYCLES_EVENT_NUM) {
867		profiling_mode = SPU_PROFILING_CYCLES;
868		ret = cell_reg_setup_spu_cycles(ctr, sys, num_ctrs);
869	} else if ((ctr[0].event >= SPU_EVENT_NUM_START) &&
870		   (ctr[0].event <= SPU_EVENT_NUM_STOP)) {
871		profiling_mode = SPU_PROFILING_EVENTS;
872		spu_cycle_reset = ctr[0].count;
873
874		/* for SPU event profiling, need to setup the
875		 * pm_signal array with the events to route the
876		 * SPU PC before making the FW call.  Note, only
877		 * one SPU event for profiling can be specified
878		 * at a time.
879		 */
880		cell_reg_setup_spu_events(ctr, sys, num_ctrs);
881	} else {
882		profiling_mode = PPU_PROFILING;
883		ret = cell_reg_setup_ppu(ctr, sys, num_ctrs);
884	}
885
886	return ret;
887}
888
889
890
891/* This function is called once for each cpu */
892static int cell_cpu_setup(struct op_counter_config *cntr)
893{
894	u32 cpu = smp_processor_id();
895	u32 num_enabled = 0;
896	int i;
897	int ret;
898
899	/* Cycle based SPU profiling does not use the performance
900	 * counters.  The trace array is configured to collect
901	 * the data.
902	 */
903	if (profiling_mode == SPU_PROFILING_CYCLES)
904		return 0;
905
906	/* There is one performance monitor per processor chip (i.e. node),
907	 * so we only need to perform this function once per node.
908	 */
909	if (cbe_get_hw_thread_id(cpu))
910		return 0;
911
912	/* Stop all counters */
913	cbe_disable_pm(cpu);
914	cbe_disable_pm_interrupts(cpu);
915
916	cbe_write_pm(cpu, pm_start_stop, 0);
917	cbe_write_pm(cpu, group_control, pm_regs.group_control);
918	cbe_write_pm(cpu, debug_bus_control, pm_regs.debug_bus_control);
919	write_pm_cntrl(cpu);
920
921	for (i = 0; i < num_counters; ++i) {
922		if (ctr_enabled & (1 << i)) {
923			pm_signal[num_enabled].cpu = cbe_cpu_to_node(cpu);
924			num_enabled++;
925		}
926	}
927
928	/*
929	 * The pm_rtas_activate_signals will return -EIO if the FW
930	 * call failed.
931	 */
932	if (profiling_mode == SPU_PROFILING_EVENTS) {
933		/* For SPU event profiling also need to setup the
934		 * pm interval timer
935		 */
936		ret = pm_rtas_activate_signals(cbe_cpu_to_node(cpu),
937					       num_enabled+2);
938		/* store PC from debug bus to Trace buffer as often
939		 * as possible (every 10 cycles)
940		 */
941		cbe_write_pm(cpu, pm_interval, NUM_INTERVAL_CYC);
942		return ret;
943	} else
944		return pm_rtas_activate_signals(cbe_cpu_to_node(cpu),
945						num_enabled);
946}
947
948#define ENTRIES	 303
949#define MAXLFSR	 0xFFFFFF
950
951/* precomputed table of 24 bit LFSR values */
952static int initial_lfsr[] = {
953 8221349, 12579195, 5379618, 10097839, 7512963, 7519310, 3955098, 10753424,
954 15507573, 7458917, 285419, 2641121, 9780088, 3915503, 6668768, 1548716,
955 4885000, 8774424, 9650099, 2044357, 2304411, 9326253, 10332526, 4421547,
956 3440748, 10179459, 13332843, 10375561, 1313462, 8375100, 5198480, 6071392,
957 9341783, 1526887, 3985002, 1439429, 13923762, 7010104, 11969769, 4547026,
958 2040072, 4025602, 3437678, 7939992, 11444177, 4496094, 9803157, 10745556,
959 3671780, 4257846, 5662259, 13196905, 3237343, 12077182, 16222879, 7587769,
960 14706824, 2184640, 12591135, 10420257, 7406075, 3648978, 11042541, 15906893,
961 11914928, 4732944, 10695697, 12928164, 11980531, 4430912, 11939291, 2917017,
962 6119256, 4172004, 9373765, 8410071, 14788383, 5047459, 5474428, 1737756,
963 15967514, 13351758, 6691285, 8034329, 2856544, 14394753, 11310160, 12149558,
964 7487528, 7542781, 15668898, 12525138, 12790975, 3707933, 9106617, 1965401,
965 16219109, 12801644, 2443203, 4909502, 8762329, 3120803, 6360315, 9309720,
966 15164599, 10844842, 4456529, 6667610, 14924259, 884312, 6234963, 3326042,
967 15973422, 13919464, 5272099, 6414643, 3909029, 2764324, 5237926, 4774955,
968 10445906, 4955302, 5203726, 10798229, 11443419, 2303395, 333836, 9646934,
969 3464726, 4159182, 568492, 995747, 10318756, 13299332, 4836017, 8237783,
970 3878992, 2581665, 11394667, 5672745, 14412947, 3159169, 9094251, 16467278,
971 8671392, 15230076, 4843545, 7009238, 15504095, 1494895, 9627886, 14485051,
972 8304291, 252817, 12421642, 16085736, 4774072, 2456177, 4160695, 15409741,
973 4902868, 5793091, 13162925, 16039714, 782255, 11347835, 14884586, 366972,
974 16308990, 11913488, 13390465, 2958444, 10340278, 1177858, 1319431, 10426302,
975 2868597, 126119, 5784857, 5245324, 10903900, 16436004, 3389013, 1742384,
976 14674502, 10279218, 8536112, 10364279, 6877778, 14051163, 1025130, 6072469,
977 1988305, 8354440, 8216060, 16342977, 13112639, 3976679, 5913576, 8816697,
978 6879995, 14043764, 3339515, 9364420, 15808858, 12261651, 2141560, 5636398,
979 10345425, 10414756, 781725, 6155650, 4746914, 5078683, 7469001, 6799140,
980 10156444, 9667150, 10116470, 4133858, 2121972, 1124204, 1003577, 1611214,
981 14304602, 16221850, 13878465, 13577744, 3629235, 8772583, 10881308, 2410386,
982 7300044, 5378855, 9301235, 12755149, 4977682, 8083074, 10327581, 6395087,
983 9155434, 15501696, 7514362, 14520507, 15808945, 3244584, 4741962, 9658130,
984 14336147, 8654727, 7969093, 15759799, 14029445, 5038459, 9894848, 8659300,
985 13699287, 8834306, 10712885, 14753895, 10410465, 3373251, 309501, 9561475,
986 5526688, 14647426, 14209836, 5339224, 207299, 14069911, 8722990, 2290950,
987 3258216, 12505185, 6007317, 9218111, 14661019, 10537428, 11731949, 9027003,
988 6641507, 9490160, 200241, 9720425, 16277895, 10816638, 1554761, 10431375,
989 7467528, 6790302, 3429078, 14633753, 14428997, 11463204, 3576212, 2003426,
990 6123687, 820520, 9992513, 15784513, 5778891, 6428165, 8388607
991};
992
993/*
994 * The hardware uses an LFSR counting sequence to determine when to capture
995 * the SPU PCs.	 An LFSR sequence is like a puesdo random number sequence
996 * where each number occurs once in the sequence but the sequence is not in
997 * numerical order. The SPU PC capture is done when the LFSR sequence reaches
998 * the last value in the sequence.  Hence the user specified value N
999 * corresponds to the LFSR number that is N from the end of the sequence.
1000 *
1001 * To avoid the time to compute the LFSR, a lookup table is used.  The 24 bit
1002 * LFSR sequence is broken into four ranges.  The spacing of the precomputed
1003 * values is adjusted in each range so the error between the user specified
1004 * number (N) of events between samples and the actual number of events based
1005 * on the precomputed value will be les then about 6.2%.  Note, if the user
1006 * specifies N < 2^16, the LFSR value that is 2^16 from the end will be used.
1007 * This is to prevent the loss of samples because the trace buffer is full.
1008 *
1009 *	   User specified N		     Step between	   Index in
1010 *					 precomputed values	 precomputed
1011 *								    table
1012 * 0		    to	2^16-1			----		      0
1013 * 2^16	    to	2^16+2^19-1		2^12		    1 to 128
1014 * 2^16+2^19	    to	2^16+2^19+2^22-1	2^15		  129 to 256
1015 * 2^16+2^19+2^22  to	2^24-1			2^18		  257 to 302
1016 *
1017 *
1018 * For example, the LFSR values in the second range are computed for 2^16,
1019 * 2^16+2^12, ... , 2^19-2^16, 2^19 and stored in the table at indicies
1020 * 1, 2,..., 127, 128.
1021 *
1022 * The 24 bit LFSR value for the nth number in the sequence can be
1023 * calculated using the following code:
1024 *
1025 * #define size 24
1026 * int calculate_lfsr(int n)
1027 * {
1028 *	int i;
1029 *	unsigned int newlfsr0;
1030 *	unsigned int lfsr = 0xFFFFFF;
1031 *	unsigned int howmany = n;
1032 *
1033 *	for (i = 2; i < howmany + 2; i++) {
1034 *		newlfsr0 = (((lfsr >> (size - 1 - 0)) & 1) ^
1035 *		((lfsr >> (size - 1 - 1)) & 1) ^
1036 *		(((lfsr >> (size - 1 - 6)) & 1) ^
1037 *		((lfsr >> (size - 1 - 23)) & 1)));
1038 *
1039 *		lfsr >>= 1;
1040 *		lfsr = lfsr | (newlfsr0 << (size - 1));
1041 *	}
1042 *	return lfsr;
1043 * }
1044 */
1045
1046#define V2_16  (0x1 << 16)
1047#define V2_19  (0x1 << 19)
1048#define V2_22  (0x1 << 22)
1049
1050static int calculate_lfsr(int n)
1051{
1052	/*
1053	 * The ranges and steps are in powers of 2 so the calculations
1054	 * can be done using shifts rather then divide.
1055	 */
1056	int index;
1057
1058	if ((n >> 16) == 0)
1059		index = 0;
1060	else if (((n - V2_16) >> 19) == 0)
1061		index = ((n - V2_16) >> 12) + 1;
1062	else if (((n - V2_16 - V2_19) >> 22) == 0)
1063		index = ((n - V2_16 - V2_19) >> 15 ) + 1 + 128;
1064	else if (((n - V2_16 - V2_19 - V2_22) >> 24) == 0)
1065		index = ((n - V2_16 - V2_19 - V2_22) >> 18 ) + 1 + 256;
1066	else
1067		index = ENTRIES-1;
1068
1069	/* make sure index is valid */
1070	if ((index >= ENTRIES) || (index < 0))
1071		index = ENTRIES-1;
1072
1073	return initial_lfsr[index];
1074}
1075
1076static int pm_rtas_activate_spu_profiling(u32 node)
1077{
1078	int ret, i;
1079	struct pm_signal pm_signal_local[NUM_SPUS_PER_NODE];
1080
1081	/*
1082	 * Set up the rtas call to configure the debug bus to
1083	 * route the SPU PCs.  Setup the pm_signal for each SPU
1084	 */
1085	for (i = 0; i < ARRAY_SIZE(pm_signal_local); i++) {
1086		pm_signal_local[i].cpu = node;
1087		pm_signal_local[i].signal_group = 41;
1088		/* spu i on word (i/2) */
1089		pm_signal_local[i].bus_word = 1 << i / 2;
1090		/* spu i */
1091		pm_signal_local[i].sub_unit = i;
1092		pm_signal_local[i].bit = 63;
1093	}
1094
1095	ret = rtas_ibm_cbe_perftools(SUBFUNC_ACTIVATE,
1096				     PASSTHRU_ENABLE, pm_signal_local,
1097				     (ARRAY_SIZE(pm_signal_local)
1098				      * sizeof(struct pm_signal)));
1099
1100	if (unlikely(ret)) {
1101		printk(KERN_WARNING "%s: rtas returned: %d\n",
1102		       __func__, ret);
1103		return -EIO;
1104	}
1105
1106	return 0;
1107}
1108
1109#ifdef CONFIG_CPU_FREQ
1110static int
1111oprof_cpufreq_notify(struct notifier_block *nb, unsigned long val, void *data)
1112{
1113	int ret = 0;
1114	struct cpufreq_freqs *frq = data;
1115	if ((val == CPUFREQ_PRECHANGE && frq->old < frq->new) ||
1116	    (val == CPUFREQ_POSTCHANGE && frq->old > frq->new))
1117		set_spu_profiling_frequency(frq->new, spu_cycle_reset);
1118	return ret;
1119}
1120
1121static struct notifier_block cpu_freq_notifier_block = {
1122	.notifier_call	= oprof_cpufreq_notify
1123};
1124#endif
1125
1126/*
1127 * Note the generic OProfile stop calls do not support returning
1128 * an error on stop.  Hence, will not return an error if the FW
1129 * calls fail on stop.	Failure to reset the debug bus is not an issue.
1130 * Failure to disable the SPU profiling is not an issue.  The FW calls
1131 * to enable the performance counters and debug bus will work even if
1132 * the hardware was not cleanly reset.
1133 */
1134static void cell_global_stop_spu_cycles(void)
1135{
1136	int subfunc, rtn_value;
1137	unsigned int lfsr_value;
1138	int cpu;
1139
1140	oprofile_running = 0;
1141	smp_wmb();
1142
1143#ifdef CONFIG_CPU_FREQ
1144	cpufreq_unregister_notifier(&cpu_freq_notifier_block,
1145				    CPUFREQ_TRANSITION_NOTIFIER);
1146#endif
1147
1148	for_each_online_cpu(cpu) {
1149		if (cbe_get_hw_thread_id(cpu))
1150			continue;
1151
1152		subfunc = 3;	/*
1153				 * 2 - activate SPU tracing,
1154				 * 3 - deactivate
1155				 */
1156		lfsr_value = 0x8f100000;
1157
1158		rtn_value = rtas_call(spu_rtas_token, 3, 1, NULL,
1159				      subfunc, cbe_cpu_to_node(cpu),
1160				      lfsr_value);
1161
1162		if (unlikely(rtn_value != 0)) {
1163			printk(KERN_ERR
1164			       "%s: rtas call ibm,cbe-spu-perftools " \
1165			       "failed, return = %d\n",
1166			       __func__, rtn_value);
1167		}
1168
1169		/* Deactivate the signals */
1170		pm_rtas_reset_signals(cbe_cpu_to_node(cpu));
1171	}
1172
1173	stop_spu_profiling_cycles();
1174}
1175
1176static void cell_global_stop_spu_events(void)
1177{
1178	int cpu;
1179	oprofile_running = 0;
1180
1181	stop_spu_profiling_events();
1182	smp_wmb();
1183
1184	for_each_online_cpu(cpu) {
1185		if (cbe_get_hw_thread_id(cpu))
1186			continue;
1187
1188		cbe_sync_irq(cbe_cpu_to_node(cpu));
1189		/* Stop the counters */
1190		cbe_disable_pm(cpu);
1191		cbe_write_pm07_control(cpu, 0, 0);
1192
1193		/* Deactivate the signals */
1194		pm_rtas_reset_signals(cbe_cpu_to_node(cpu));
1195
1196		/* Deactivate interrupts */
1197		cbe_disable_pm_interrupts(cpu);
1198	}
1199	del_timer_sync(&timer_spu_event_swap);
1200}
1201
1202static void cell_global_stop_ppu(void)
1203{
1204	int cpu;
1205
1206	/*
1207	 * This routine will be called once for the system.
1208	 * There is one performance monitor per node, so we
1209	 * only need to perform this function once per node.
1210	 */
1211	del_timer_sync(&timer_virt_cntr);
1212	oprofile_running = 0;
1213	smp_wmb();
1214
1215	for_each_online_cpu(cpu) {
1216		if (cbe_get_hw_thread_id(cpu))
1217			continue;
1218
1219		cbe_sync_irq(cbe_cpu_to_node(cpu));
1220		/* Stop the counters */
1221		cbe_disable_pm(cpu);
1222
1223		/* Deactivate the signals */
1224		pm_rtas_reset_signals(cbe_cpu_to_node(cpu));
1225
1226		/* Deactivate interrupts */
1227		cbe_disable_pm_interrupts(cpu);
1228	}
1229}
1230
1231static void cell_global_stop(void)
1232{
1233	if (profiling_mode == PPU_PROFILING)
1234		cell_global_stop_ppu();
1235	else if (profiling_mode == SPU_PROFILING_EVENTS)
1236		cell_global_stop_spu_events();
1237	else
1238		cell_global_stop_spu_cycles();
1239}
1240
1241static int cell_global_start_spu_cycles(struct op_counter_config *ctr)
1242{
1243	int subfunc;
1244	unsigned int lfsr_value;
1245	int cpu;
1246	int ret;
1247	int rtas_error;
1248	unsigned int cpu_khzfreq = 0;
1249
1250	/* The SPU profiling uses time-based profiling based on
1251	 * cpu frequency, so if configured with the CPU_FREQ
1252	 * option, we should detect frequency changes and react
1253	 * accordingly.
1254	 */
1255#ifdef CONFIG_CPU_FREQ
1256	ret = cpufreq_register_notifier(&cpu_freq_notifier_block,
1257					CPUFREQ_TRANSITION_NOTIFIER);
1258	if (ret < 0)
1259		/* this is not a fatal error */
1260		printk(KERN_ERR "CPU freq change registration failed: %d\n",
1261		       ret);
1262
1263	else
1264		cpu_khzfreq = cpufreq_quick_get(smp_processor_id());
1265#endif
1266
1267	set_spu_profiling_frequency(cpu_khzfreq, spu_cycle_reset);
1268
1269	for_each_online_cpu(cpu) {
1270		if (cbe_get_hw_thread_id(cpu))
1271			continue;
1272
1273		/*
1274		 * Setup SPU cycle-based profiling.
1275		 * Set perf_mon_control bit 0 to a zero before
1276		 * enabling spu collection hardware.
1277		 */
1278		cbe_write_pm(cpu, pm_control, 0);
1279
1280		if (spu_cycle_reset > MAX_SPU_COUNT)
1281			/* use largest possible value */
1282			lfsr_value = calculate_lfsr(MAX_SPU_COUNT-1);
1283		else
1284			lfsr_value = calculate_lfsr(spu_cycle_reset);
1285
1286		/* must use a non zero value. Zero disables data collection. */
1287		if (lfsr_value == 0)
1288			lfsr_value = calculate_lfsr(1);
1289
1290		lfsr_value = lfsr_value << 8; /* shift lfsr to correct
1291						* register location
1292						*/
1293
1294		/* debug bus setup */
1295		ret = pm_rtas_activate_spu_profiling(cbe_cpu_to_node(cpu));
1296
1297		if (unlikely(ret)) {
1298			rtas_error = ret;
1299			goto out;
1300		}
1301
1302
1303		subfunc = 2;	/* 2 - activate SPU tracing, 3 - deactivate */
1304
1305		/* start profiling */
1306		ret = rtas_call(spu_rtas_token, 3, 1, NULL, subfunc,
1307				cbe_cpu_to_node(cpu), lfsr_value);
1308
1309		if (unlikely(ret != 0)) {
1310			printk(KERN_ERR
1311			       "%s: rtas call ibm,cbe-spu-perftools failed, " \
1312			       "return = %d\n", __func__, ret);
1313			rtas_error = -EIO;
1314			goto out;
1315		}
1316	}
1317
1318	rtas_error = start_spu_profiling_cycles(spu_cycle_reset);
1319	if (rtas_error)
1320		goto out_stop;
1321
1322	oprofile_running = 1;
1323	return 0;
1324
1325out_stop:
1326	cell_global_stop_spu_cycles();	/* clean up the PMU/debug bus */
1327out:
1328	return rtas_error;
1329}
1330
1331static int cell_global_start_spu_events(struct op_counter_config *ctr)
1332{
1333	int cpu;
1334	u32 interrupt_mask = 0;
1335	int rtn = 0;
1336
1337	hdw_thread = 0;
1338
1339	/* spu event profiling, uses the performance counters to generate
1340	 * an interrupt.  The hardware is setup to store the SPU program
1341	 * counter into the trace array.  The occurrence mode is used to
1342	 * enable storing data to the trace buffer.  The bits are set
1343	 * to send/store the SPU address in the trace buffer.  The debug
1344	 * bus must be setup to route the SPU program counter onto the
1345	 * debug bus.  The occurrence data in the trace buffer is not used.
1346	 */
1347
1348	/* This routine gets called once for the system.
1349	 * There is one performance monitor per node, so we
1350	 * only need to perform this function once per node.
1351	 */
1352
1353	for_each_online_cpu(cpu) {
1354		if (cbe_get_hw_thread_id(cpu))
1355			continue;
1356
1357		/*
1358		 * Setup SPU event-based profiling.
1359		 * Set perf_mon_control bit 0 to a zero before
1360		 * enabling spu collection hardware.
1361		 *
1362		 * Only support one SPU event on one SPU per node.
1363		 */
1364		if (ctr_enabled & 1) {
1365			cbe_write_ctr(cpu, 0, reset_value[0]);
1366			enable_ctr(cpu, 0, pm_regs.pm07_cntrl);
1367			interrupt_mask |=
1368				CBE_PM_CTR_OVERFLOW_INTR(0);
1369		} else {
1370			/* Disable counter */
1371			cbe_write_pm07_control(cpu, 0, 0);
1372		}
1373
1374		cbe_get_and_clear_pm_interrupts(cpu);
1375		cbe_enable_pm_interrupts(cpu, hdw_thread, interrupt_mask);
1376		cbe_enable_pm(cpu);
1377
1378		/* clear the trace buffer */
1379		cbe_write_pm(cpu, trace_address, 0);
1380	}
1381
1382	/* Start the timer to time slice collecting the event profile
1383	 * on each of the SPUs.  Note, can collect profile on one SPU
1384	 * per node at a time.
1385	 */
1386	start_spu_event_swap();
1387	start_spu_profiling_events();
1388	oprofile_running = 1;
1389	smp_wmb();
1390
1391	return rtn;
1392}
1393
1394static int cell_global_start_ppu(struct op_counter_config *ctr)
1395{
1396	u32 cpu, i;
1397	u32 interrupt_mask = 0;
1398
1399	/* This routine gets called once for the system.
1400	 * There is one performance monitor per node, so we
1401	 * only need to perform this function once per node.
1402	 */
1403	for_each_online_cpu(cpu) {
1404		if (cbe_get_hw_thread_id(cpu))
1405			continue;
1406
1407		interrupt_mask = 0;
1408
1409		for (i = 0; i < num_counters; ++i) {
1410			if (ctr_enabled & (1 << i)) {
1411				cbe_write_ctr(cpu, i, reset_value[i]);
1412				enable_ctr(cpu, i, pm_regs.pm07_cntrl);
1413				interrupt_mask |= CBE_PM_CTR_OVERFLOW_INTR(i);
1414			} else {
1415				/* Disable counter */
1416				cbe_write_pm07_control(cpu, i, 0);
1417			}
1418		}
1419
1420		cbe_get_and_clear_pm_interrupts(cpu);
1421		cbe_enable_pm_interrupts(cpu, hdw_thread, interrupt_mask);
1422		cbe_enable_pm(cpu);
1423	}
1424
1425	virt_cntr_inter_mask = interrupt_mask;
1426	oprofile_running = 1;
1427	smp_wmb();
1428
1429	/*
1430	 * NOTE: start_virt_cntrs will result in cell_virtual_cntr() being
1431	 * executed which manipulates the PMU.	We start the "virtual counter"
1432	 * here so that we do not need to synchronize access to the PMU in
1433	 * the above for-loop.
1434	 */
1435	start_virt_cntrs();
1436
1437	return 0;
1438}
1439
1440static int cell_global_start(struct op_counter_config *ctr)
1441{
1442	if (profiling_mode == SPU_PROFILING_CYCLES)
1443		return cell_global_start_spu_cycles(ctr);
1444	else if (profiling_mode == SPU_PROFILING_EVENTS)
1445		return cell_global_start_spu_events(ctr);
1446	else
1447		return cell_global_start_ppu(ctr);
1448}
1449
1450
1451/* The SPU interrupt handler
1452 *
1453 * SPU event profiling works as follows:
1454 * The pm_signal[0] holds the one SPU event to be measured.  It is routed on
1455 * the debug bus using word 0 or 1.  The value of pm_signal[1] and
1456 * pm_signal[2] contain the necessary events to route the SPU program
1457 * counter for the selected SPU onto the debug bus using words 2 and 3.
1458 * The pm_interval register is setup to write the SPU PC value into the
1459 * trace buffer at the maximum rate possible.  The trace buffer is configured
1460 * to store the PCs, wrapping when it is full.  The performance counter is
1461 * initialized to the max hardware count minus the number of events, N, between
1462 * samples.  Once the N events have occurred, a HW counter overflow occurs
1463 * causing the generation of a HW counter interrupt which also stops the
1464 * writing of the SPU PC values to the trace buffer.  Hence the last PC
1465 * written to the trace buffer is the SPU PC that we want.  Unfortunately,
1466 * we have to read from the beginning of the trace buffer to get to the
1467 * last value written.  We just hope the PPU has nothing better to do then
1468 * service this interrupt. The PC for the specific SPU being profiled is
1469 * extracted from the trace buffer processed and stored.  The trace buffer
1470 * is cleared, interrupts are cleared, the counter is reset to max - N.
1471 * A kernel timer is used to periodically call the routine spu_evnt_swap()
1472 * to switch to the next physical SPU in the node to profile in round robbin
1473 * order.  This way data is collected for all SPUs on the node. It does mean
1474 * that we need to use a relatively small value of N to ensure enough samples
1475 * on each SPU are collected each SPU is being profiled 1/8 of the time.
1476 * It may also be necessary to use a longer sample collection period.
1477 */
1478static void cell_handle_interrupt_spu(struct pt_regs *regs,
1479				      struct op_counter_config *ctr)
1480{
1481	u32 cpu, cpu_tmp;
1482	u64 trace_entry;
1483	u32 interrupt_mask;
1484	u64 trace_buffer[2];
1485	u64 last_trace_buffer;
1486	u32 sample;
1487	u32 trace_addr;
1488	unsigned long sample_array_lock_flags;
1489	int spu_num;
1490	unsigned long flags;
1491
1492	/* Make sure spu event interrupt handler and spu event swap
1493	 * don't access the counters simultaneously.
1494	 */
1495	cpu = smp_processor_id();
1496	spin_lock_irqsave(&cntr_lock, flags);
1497
1498	cpu_tmp = cpu;
1499	cbe_disable_pm(cpu);
1500
1501	interrupt_mask = cbe_get_and_clear_pm_interrupts(cpu);
1502
1503	sample = 0xABCDEF;
1504	trace_entry = 0xfedcba;
1505	last_trace_buffer = 0xdeadbeaf;
1506
1507	if ((oprofile_running == 1) && (interrupt_mask != 0)) {
1508		/* disable writes to trace buff */
1509		cbe_write_pm(cpu, pm_interval, 0);
1510
1511		/* only have one perf cntr being used, cntr 0 */
1512		if ((interrupt_mask & CBE_PM_CTR_OVERFLOW_INTR(0))
1513		    && ctr[0].enabled)
1514			/* The SPU PC values will be read
1515			 * from the trace buffer, reset counter
1516			 */
1517
1518			cbe_write_ctr(cpu, 0, reset_value[0]);
1519
1520		trace_addr = cbe_read_pm(cpu, trace_address);
1521
1522		while (!(trace_addr & CBE_PM_TRACE_BUF_EMPTY)) {
1523			/* There is data in the trace buffer to process
1524			 * Read the buffer until you get to the last
1525			 * entry.  This is the value we want.
1526			 */
1527
1528			cbe_read_trace_buffer(cpu, trace_buffer);
1529			trace_addr = cbe_read_pm(cpu, trace_address);
1530		}
1531
1532		/* SPU Address 16 bit count format for 128 bit
1533		 * HW trace buffer is used for the SPU PC storage
1534		 *    HDR bits          0:15
1535		 *    SPU Addr 0 bits   16:31
1536		 *    SPU Addr 1 bits   32:47
1537		 *    unused bits       48:127
1538		 *
1539		 * HDR: bit4 = 1 SPU Address 0 valid
1540		 * HDR: bit5 = 1 SPU Address 1 valid
1541		 *  - unfortunately, the valid bits don't seem to work
1542		 *
1543		 * Note trace_buffer[0] holds bits 0:63 of the HW
1544		 * trace buffer, trace_buffer[1] holds bits 64:127
1545		 */
1546
1547		trace_entry = trace_buffer[0]
1548			& 0x00000000FFFF0000;
1549
1550		/* only top 16 of the 18 bit SPU PC address
1551		 * is stored in trace buffer, hence shift right
1552		 * by 16 -2 bits */
1553		sample = trace_entry >> 14;
1554		last_trace_buffer = trace_buffer[0];
1555
1556		spu_num = spu_evnt_phys_spu_indx
1557			+ (cbe_cpu_to_node(cpu) * NUM_SPUS_PER_NODE);
1558
1559		/* make sure only one process at a time is calling
1560		 * spu_sync_buffer()
1561		 */
1562		spin_lock_irqsave(&oprof_spu_smpl_arry_lck,
1563				  sample_array_lock_flags);
1564		spu_sync_buffer(spu_num, &sample, 1);
1565		spin_unlock_irqrestore(&oprof_spu_smpl_arry_lck,
1566				       sample_array_lock_flags);
1567
1568		smp_wmb();    /* insure spu event buffer updates are written
1569			       * don't want events intermingled... */
1570
1571		/* The counters were frozen by the interrupt.
1572		 * Reenable the interrupt and restart the counters.
1573		 */
1574		cbe_write_pm(cpu, pm_interval, NUM_INTERVAL_CYC);
1575		cbe_enable_pm_interrupts(cpu, hdw_thread,
1576					 virt_cntr_inter_mask);
1577
1578		/* clear the trace buffer, re-enable writes to trace buff */
1579		cbe_write_pm(cpu, trace_address, 0);
1580		cbe_write_pm(cpu, pm_interval, NUM_INTERVAL_CYC);
1581
1582		/* The writes to the various performance counters only writes
1583		 * to a latch.  The new values (interrupt setting bits, reset
1584		 * counter value etc.) are not copied to the actual registers
1585		 * until the performance monitor is enabled.  In order to get
1586		 * this to work as desired, the performance monitor needs to
1587		 * be disabled while writing to the latches.  This is a
1588		 * HW design issue.
1589		 */
1590		write_pm_cntrl(cpu);
1591		cbe_enable_pm(cpu);
1592	}
1593	spin_unlock_irqrestore(&cntr_lock, flags);
1594}
1595
1596static void cell_handle_interrupt_ppu(struct pt_regs *regs,
1597				      struct op_counter_config *ctr)
1598{
1599	u32 cpu;
1600	u64 pc;
1601	int is_kernel;
1602	unsigned long flags = 0;
1603	u32 interrupt_mask;
1604	int i;
1605
1606	cpu = smp_processor_id();
1607
1608	/*
1609	 * Need to make sure the interrupt handler and the virt counter
1610	 * routine are not running at the same time. See the
1611	 * cell_virtual_cntr() routine for additional comments.
1612	 */
1613	spin_lock_irqsave(&cntr_lock, flags);
1614
1615	/*
1616	 * Need to disable and reenable the performance counters
1617	 * to get the desired behavior from the hardware.  This
1618	 * is hardware specific.
1619	 */
1620
1621	cbe_disable_pm(cpu);
1622
1623	interrupt_mask = cbe_get_and_clear_pm_interrupts(cpu);
1624
1625	/*
1626	 * If the interrupt mask has been cleared, then the virt cntr
1627	 * has cleared the interrupt.  When the thread that generated
1628	 * the interrupt is restored, the data count will be restored to
1629	 * 0xffffff0 to cause the interrupt to be regenerated.
1630	 */
1631
1632	if ((oprofile_running == 1) && (interrupt_mask != 0)) {
1633		pc = regs->nip;
1634		is_kernel = is_kernel_addr(pc);
1635
1636		for (i = 0; i < num_counters; ++i) {
1637			if ((interrupt_mask & CBE_PM_CTR_OVERFLOW_INTR(i))
1638			    && ctr[i].enabled) {
1639				oprofile_add_ext_sample(pc, regs, i, is_kernel);
1640				cbe_write_ctr(cpu, i, reset_value[i]);
1641			}
1642		}
1643
1644		/*
1645		 * The counters were frozen by the interrupt.
1646		 * Reenable the interrupt and restart the counters.
1647		 * If there was a race between the interrupt handler and
1648		 * the virtual counter routine.	 The virtual counter
1649		 * routine may have cleared the interrupts.  Hence must
1650		 * use the virt_cntr_inter_mask to re-enable the interrupts.
1651		 */
1652		cbe_enable_pm_interrupts(cpu, hdw_thread,
1653					 virt_cntr_inter_mask);
1654
1655		/*
1656		 * The writes to the various performance counters only writes
1657		 * to a latch.	The new values (interrupt setting bits, reset
1658		 * counter value etc.) are not copied to the actual registers
1659		 * until the performance monitor is enabled.  In order to get
1660		 * this to work as desired, the performance monitor needs to
1661		 * be disabled while writing to the latches.  This is a
1662		 * HW design issue.
1663		 */
1664		cbe_enable_pm(cpu);
1665	}
1666	spin_unlock_irqrestore(&cntr_lock, flags);
1667}
1668
1669static void cell_handle_interrupt(struct pt_regs *regs,
1670				  struct op_counter_config *ctr)
1671{
1672	if (profiling_mode == PPU_PROFILING)
1673		cell_handle_interrupt_ppu(regs, ctr);
1674	else
1675		cell_handle_interrupt_spu(regs, ctr);
1676}
1677
1678/*
1679 * This function is called from the generic OProfile
1680 * driver.  When profiling PPUs, we need to do the
1681 * generic sync start; otherwise, do spu_sync_start.
1682 */
1683static int cell_sync_start(void)
1684{
1685	if ((profiling_mode == SPU_PROFILING_CYCLES) ||
1686	    (profiling_mode == SPU_PROFILING_EVENTS))
1687		return spu_sync_start();
1688	else
1689		return DO_GENERIC_SYNC;
1690}
1691
1692static int cell_sync_stop(void)
1693{
1694	if ((profiling_mode == SPU_PROFILING_CYCLES) ||
1695	    (profiling_mode == SPU_PROFILING_EVENTS))
1696		return spu_sync_stop();
1697	else
1698		return 1;
1699}
1700
1701struct op_powerpc_model op_model_cell = {
1702	.reg_setup = cell_reg_setup,
1703	.cpu_setup = cell_cpu_setup,
1704	.global_start = cell_global_start,
1705	.global_stop = cell_global_stop,
1706	.sync_start = cell_sync_start,
1707	.sync_stop = cell_sync_stop,
1708	.handle_interrupt = cell_handle_interrupt,
1709};
1710