xref: /openbmc/linux/arch/sparc/kernel/pcr.c (revision 63705da3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* pcr.c: Generic sparc64 performance counter infrastructure.
3  *
4  * Copyright (C) 2009 David S. Miller (davem@davemloft.net)
5  */
6 #include <linux/kernel.h>
7 #include <linux/export.h>
8 #include <linux/init.h>
9 #include <linux/irq.h>
10 
11 #include <linux/irq_work.h>
12 #include <linux/ftrace.h>
13 
14 #include <asm/pil.h>
15 #include <asm/pcr.h>
16 #include <asm/nmi.h>
17 #include <asm/asi.h>
18 #include <asm/spitfire.h>
19 
20 /* This code is shared between various users of the performance
21  * counters.  Users will be oprofile, pseudo-NMI watchdog, and the
22  * perf_event support layer.
23  */
24 
25 /* Performance counter interrupts run unmasked at PIL level 15.
26  * Therefore we can't do things like wakeups and other work
27  * that expects IRQ disabling to be adhered to in locking etc.
28  *
29  * Therefore in such situations we defer the work by signalling
30  * a lower level cpu IRQ.
31  */
32 void __irq_entry deferred_pcr_work_irq(int irq, struct pt_regs *regs)
33 {
34 	struct pt_regs *old_regs;
35 
36 	clear_softint(1 << PIL_DEFERRED_PCR_WORK);
37 
38 	old_regs = set_irq_regs(regs);
39 	irq_enter();
40 #ifdef CONFIG_IRQ_WORK
41 	irq_work_run();
42 #endif
43 	irq_exit();
44 	set_irq_regs(old_regs);
45 }
46 
47 void arch_irq_work_raise(void)
48 {
49 	set_softint(1 << PIL_DEFERRED_PCR_WORK);
50 }
51 
52 const struct pcr_ops *pcr_ops;
53 EXPORT_SYMBOL_GPL(pcr_ops);
54 
55 static u64 direct_pcr_read(unsigned long reg_num)
56 {
57 	u64 val;
58 
59 	WARN_ON_ONCE(reg_num != 0);
60 	__asm__ __volatile__("rd %%pcr, %0" : "=r" (val));
61 	return val;
62 }
63 
64 static void direct_pcr_write(unsigned long reg_num, u64 val)
65 {
66 	WARN_ON_ONCE(reg_num != 0);
67 	__asm__ __volatile__("wr %0, 0x0, %%pcr" : : "r" (val));
68 }
69 
70 static u64 direct_pic_read(unsigned long reg_num)
71 {
72 	u64 val;
73 
74 	WARN_ON_ONCE(reg_num != 0);
75 	__asm__ __volatile__("rd %%pic, %0" : "=r" (val));
76 	return val;
77 }
78 
79 static void direct_pic_write(unsigned long reg_num, u64 val)
80 {
81 	WARN_ON_ONCE(reg_num != 0);
82 
83 	/* Blackbird errata workaround.  See commentary in
84 	 * arch/sparc64/kernel/smp.c:smp_percpu_timer_interrupt()
85 	 * for more information.
86 	 */
87 	__asm__ __volatile__("ba,pt	%%xcc, 99f\n\t"
88 			     " nop\n\t"
89 			     ".align	64\n"
90 			  "99:wr	%0, 0x0, %%pic\n\t"
91 			     "rd	%%pic, %%g0" : : "r" (val));
92 }
93 
94 static u64 direct_picl_value(unsigned int nmi_hz)
95 {
96 	u32 delta = local_cpu_data().clock_tick / nmi_hz;
97 
98 	return ((u64)((0 - delta) & 0xffffffff)) << 32;
99 }
100 
101 static const struct pcr_ops direct_pcr_ops = {
102 	.read_pcr		= direct_pcr_read,
103 	.write_pcr		= direct_pcr_write,
104 	.read_pic		= direct_pic_read,
105 	.write_pic		= direct_pic_write,
106 	.nmi_picl_value		= direct_picl_value,
107 	.pcr_nmi_enable		= (PCR_PIC_PRIV | PCR_STRACE | PCR_UTRACE),
108 	.pcr_nmi_disable	= PCR_PIC_PRIV,
109 };
110 
111 static void n2_pcr_write(unsigned long reg_num, u64 val)
112 {
113 	unsigned long ret;
114 
115 	WARN_ON_ONCE(reg_num != 0);
116 	if (val & PCR_N2_HTRACE) {
117 		ret = sun4v_niagara2_setperf(HV_N2_PERF_SPARC_CTL, val);
118 		if (ret != HV_EOK)
119 			direct_pcr_write(reg_num, val);
120 	} else
121 		direct_pcr_write(reg_num, val);
122 }
123 
124 static u64 n2_picl_value(unsigned int nmi_hz)
125 {
126 	u32 delta = local_cpu_data().clock_tick / (nmi_hz << 2);
127 
128 	return ((u64)((0 - delta) & 0xffffffff)) << 32;
129 }
130 
131 static const struct pcr_ops n2_pcr_ops = {
132 	.read_pcr		= direct_pcr_read,
133 	.write_pcr		= n2_pcr_write,
134 	.read_pic		= direct_pic_read,
135 	.write_pic		= direct_pic_write,
136 	.nmi_picl_value		= n2_picl_value,
137 	.pcr_nmi_enable		= (PCR_PIC_PRIV | PCR_STRACE | PCR_UTRACE |
138 				   PCR_N2_TOE_OV1 |
139 				   (2 << PCR_N2_SL1_SHIFT) |
140 				   (0xff << PCR_N2_MASK1_SHIFT)),
141 	.pcr_nmi_disable	= PCR_PIC_PRIV,
142 };
143 
144 static u64 n4_pcr_read(unsigned long reg_num)
145 {
146 	unsigned long val;
147 
148 	(void) sun4v_vt_get_perfreg(reg_num, &val);
149 
150 	return val;
151 }
152 
153 static void n4_pcr_write(unsigned long reg_num, u64 val)
154 {
155 	(void) sun4v_vt_set_perfreg(reg_num, val);
156 }
157 
158 static u64 n4_pic_read(unsigned long reg_num)
159 {
160 	unsigned long val;
161 
162 	__asm__ __volatile__("ldxa [%1] %2, %0"
163 			     : "=r" (val)
164 			     : "r" (reg_num * 0x8UL), "i" (ASI_PIC));
165 
166 	return val;
167 }
168 
169 static void n4_pic_write(unsigned long reg_num, u64 val)
170 {
171 	__asm__ __volatile__("stxa %0, [%1] %2"
172 			     : /* no outputs */
173 			     : "r" (val), "r" (reg_num * 0x8UL), "i" (ASI_PIC));
174 }
175 
176 static u64 n4_picl_value(unsigned int nmi_hz)
177 {
178 	u32 delta = local_cpu_data().clock_tick / (nmi_hz << 2);
179 
180 	return ((u64)((0 - delta) & 0xffffffff));
181 }
182 
183 static const struct pcr_ops n4_pcr_ops = {
184 	.read_pcr		= n4_pcr_read,
185 	.write_pcr		= n4_pcr_write,
186 	.read_pic		= n4_pic_read,
187 	.write_pic		= n4_pic_write,
188 	.nmi_picl_value		= n4_picl_value,
189 	.pcr_nmi_enable		= (PCR_N4_PICNPT | PCR_N4_STRACE |
190 				   PCR_N4_UTRACE | PCR_N4_TOE |
191 				   (26 << PCR_N4_SL_SHIFT)),
192 	.pcr_nmi_disable	= PCR_N4_PICNPT,
193 };
194 
195 static u64 n5_pcr_read(unsigned long reg_num)
196 {
197 	unsigned long val;
198 
199 	(void) sun4v_t5_get_perfreg(reg_num, &val);
200 
201 	return val;
202 }
203 
204 static void n5_pcr_write(unsigned long reg_num, u64 val)
205 {
206 	(void) sun4v_t5_set_perfreg(reg_num, val);
207 }
208 
209 static const struct pcr_ops n5_pcr_ops = {
210 	.read_pcr		= n5_pcr_read,
211 	.write_pcr		= n5_pcr_write,
212 	.read_pic		= n4_pic_read,
213 	.write_pic		= n4_pic_write,
214 	.nmi_picl_value		= n4_picl_value,
215 	.pcr_nmi_enable		= (PCR_N4_PICNPT | PCR_N4_STRACE |
216 				   PCR_N4_UTRACE | PCR_N4_TOE |
217 				   (26 << PCR_N4_SL_SHIFT)),
218 	.pcr_nmi_disable	= PCR_N4_PICNPT,
219 };
220 
221 static u64 m7_pcr_read(unsigned long reg_num)
222 {
223 	unsigned long val;
224 
225 	(void) sun4v_m7_get_perfreg(reg_num, &val);
226 
227 	return val;
228 }
229 
230 static void m7_pcr_write(unsigned long reg_num, u64 val)
231 {
232 	(void) sun4v_m7_set_perfreg(reg_num, val);
233 }
234 
235 static const struct pcr_ops m7_pcr_ops = {
236 	.read_pcr		= m7_pcr_read,
237 	.write_pcr		= m7_pcr_write,
238 	.read_pic		= n4_pic_read,
239 	.write_pic		= n4_pic_write,
240 	.nmi_picl_value		= n4_picl_value,
241 	.pcr_nmi_enable		= (PCR_N4_PICNPT | PCR_N4_STRACE |
242 				   PCR_N4_UTRACE | PCR_N4_TOE |
243 				   (26 << PCR_N4_SL_SHIFT)),
244 	.pcr_nmi_disable	= PCR_N4_PICNPT,
245 };
246 
247 static unsigned long perf_hsvc_group;
248 static unsigned long perf_hsvc_major;
249 static unsigned long perf_hsvc_minor;
250 
251 static int __init register_perf_hsvc(void)
252 {
253 	unsigned long hverror;
254 
255 	if (tlb_type == hypervisor) {
256 		switch (sun4v_chip_type) {
257 		case SUN4V_CHIP_NIAGARA1:
258 			perf_hsvc_group = HV_GRP_NIAG_PERF;
259 			break;
260 
261 		case SUN4V_CHIP_NIAGARA2:
262 			perf_hsvc_group = HV_GRP_N2_CPU;
263 			break;
264 
265 		case SUN4V_CHIP_NIAGARA3:
266 			perf_hsvc_group = HV_GRP_KT_CPU;
267 			break;
268 
269 		case SUN4V_CHIP_NIAGARA4:
270 			perf_hsvc_group = HV_GRP_VT_CPU;
271 			break;
272 
273 		case SUN4V_CHIP_NIAGARA5:
274 			perf_hsvc_group = HV_GRP_T5_CPU;
275 			break;
276 
277 		case SUN4V_CHIP_SPARC_M7:
278 			perf_hsvc_group = HV_GRP_M7_PERF;
279 			break;
280 
281 		default:
282 			return -ENODEV;
283 		}
284 
285 
286 		perf_hsvc_major = 1;
287 		perf_hsvc_minor = 0;
288 		hverror = sun4v_hvapi_register(perf_hsvc_group,
289 					       perf_hsvc_major,
290 					       &perf_hsvc_minor);
291 		if (hverror) {
292 			pr_err("perfmon: Could not register hvapi(0x%lx).\n",
293 			       hverror);
294 			return -ENODEV;
295 		}
296 	}
297 	return 0;
298 }
299 
300 static void __init unregister_perf_hsvc(void)
301 {
302 	if (tlb_type != hypervisor)
303 		return;
304 	sun4v_hvapi_unregister(perf_hsvc_group);
305 }
306 
307 static int __init setup_sun4v_pcr_ops(void)
308 {
309 	int ret = 0;
310 
311 	switch (sun4v_chip_type) {
312 	case SUN4V_CHIP_NIAGARA1:
313 	case SUN4V_CHIP_NIAGARA2:
314 	case SUN4V_CHIP_NIAGARA3:
315 		pcr_ops = &n2_pcr_ops;
316 		break;
317 
318 	case SUN4V_CHIP_NIAGARA4:
319 		pcr_ops = &n4_pcr_ops;
320 		break;
321 
322 	case SUN4V_CHIP_NIAGARA5:
323 		pcr_ops = &n5_pcr_ops;
324 		break;
325 
326 	case SUN4V_CHIP_SPARC_M7:
327 		pcr_ops = &m7_pcr_ops;
328 		break;
329 
330 	default:
331 		ret = -ENODEV;
332 		break;
333 	}
334 
335 	return ret;
336 }
337 
338 int __init pcr_arch_init(void)
339 {
340 	int err = register_perf_hsvc();
341 
342 	if (err)
343 		return err;
344 
345 	switch (tlb_type) {
346 	case hypervisor:
347 		err = setup_sun4v_pcr_ops();
348 		if (err)
349 			goto out_unregister;
350 		break;
351 
352 	case cheetah:
353 	case cheetah_plus:
354 		pcr_ops = &direct_pcr_ops;
355 		break;
356 
357 	case spitfire:
358 		/* UltraSPARC-I/II and derivatives lack a profile
359 		 * counter overflow interrupt so we can't make use of
360 		 * their hardware currently.
361 		 */
362 		fallthrough;
363 	default:
364 		err = -ENODEV;
365 		goto out_unregister;
366 	}
367 
368 	return nmi_init();
369 
370 out_unregister:
371 	unregister_perf_hsvc();
372 	return err;
373 }
374