xref: /illumos-gate/usr/src/uts/sun4/io/cbe.c (revision 1a2d662a91cee3bf82f41cd47c7ae6f3825d9db2)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/param.h>
27 #include <sys/time.h>
28 #include <sys/systm.h>
29 #include <sys/cmn_err.h>
30 #include <sys/debug.h>
31 #include <sys/clock.h>
32 #include <sys/x_call.h>
33 #include <sys/cpuvar.h>
34 #include <sys/promif.h>
35 #include <sys/kmem.h>
36 #include <sys/machsystm.h>
37 #include <sys/ivintr.h>
38 #include <sys/cyclic.h>
39 #include <sys/cyclic_impl.h>
40 
41 uint64_t cbe_level14_inum;
42 cyclic_id_t cbe_hres_cyclic;
43 
44 static hrtime_t cbe_hrtime_max;
45 static hrtime_t cbe_suspend_delta = 0;
46 static hrtime_t cbe_suspend_time = 0;
47 
48 static uint64_t
49 hrtime2tick(hrtime_t ts)
50 {
51 	hrtime_t q = ts / NANOSEC;
52 	hrtime_t r = ts - (q * NANOSEC);
53 
54 	return (q * sys_tick_freq + ((r * sys_tick_freq) / NANOSEC));
55 }
56 
57 uint64_t
58 unscalehrtime(hrtime_t ts)
59 {
60 	uint64_t unscale = 0;
61 	hrtime_t rescale;
62 	hrtime_t diff = ts;
63 
64 	while (diff > nsec_per_sys_tick) {
65 		unscale += hrtime2tick(diff);
66 		rescale = unscale;
67 		scalehrtime(&rescale);
68 		diff = ts - rescale;
69 	}
70 
71 	return (unscale);
72 }
73 
74 static int
75 cbe_level1()
76 {
77 	cyclic_softint(CPU, CY_LOW_LEVEL);
78 	return (1);
79 }
80 
81 static int
82 cbe_level10()
83 {
84 	cyclic_softint(CPU, CY_LOCK_LEVEL);
85 	return (1);
86 }
87 
88 /*ARGSUSED*/
89 static void
90 cbe_enable(cyb_arg_t arg)
91 {
92 	int pstate_save = disable_vec_intr();
93 
94 	intr_enqueue_req(PIL_14, cbe_level14_inum);
95 	enable_vec_intr(pstate_save);
96 }
97 
98 /*ARGSUSED*/
99 static void
100 cbe_disable(cyb_arg_t arg)
101 {
102 	int pstate_save = disable_vec_intr();
103 
104 	tickcmpr_disable();
105 	intr_dequeue_req(PIL_14, cbe_level14_inum);
106 	enable_vec_intr(pstate_save);
107 }
108 
109 /*ARGSUSED*/
110 static void
111 cbe_reprogram(cyb_arg_t arg, hrtime_t time)
112 {
113 	if (time >= cbe_hrtime_max)
114 		time = cbe_hrtime_max;
115 
116 	tickcmpr_set(unscalehrtime(time));
117 }
118 
119 static void
120 cbe_softint(cyb_arg_t arg, cyc_level_t level)
121 {
122 	cbe_data_t *data = (cbe_data_t *)arg;
123 
124 	switch (level) {
125 	case CY_LOW_LEVEL:
126 		setsoftint(data->cbe_level1_inum);
127 		break;
128 	case CY_LOCK_LEVEL:
129 		setsoftint(data->cbe_level10_inum);
130 		break;
131 	default:
132 		panic("cbe_softint: unexpected soft level %d", level);
133 	}
134 }
135 
136 /*ARGSUSED*/
137 static cyc_cookie_t
138 cbe_set_level(cyb_arg_t arg, cyc_level_t level)
139 {
140 	int ipl;
141 
142 	switch (level) {
143 	case CY_LOW_LEVEL:
144 		ipl = CBE_LOW_PIL;
145 		break;
146 	case CY_LOCK_LEVEL:
147 		ipl = CBE_LOCK_PIL;
148 		break;
149 	case CY_HIGH_LEVEL:
150 		ipl = CBE_HIGH_PIL;
151 		break;
152 	default:
153 		panic("cbe_set_level: unexpected level %d", level);
154 	}
155 
156 	return (splr(ipl));
157 }
158 
159 /*ARGSUSED*/
160 static void
161 cbe_restore_level(cyb_arg_t arg, cyc_cookie_t cookie)
162 {
163 	splx(cookie);
164 }
165 
166 static void
167 cbe_xcall_handler(uint64_t arg1, uint64_t arg2)
168 {
169 	cyc_func_t func = (cyc_func_t)arg1;
170 	void *arg = (void *)arg2;
171 
172 	(*func)(arg);
173 }
174 
175 /*ARGSUSED*/
176 static void
177 cbe_xcall(cyb_arg_t arg, cpu_t *dest, cyc_func_t func, void *farg)
178 {
179 	kpreempt_disable();
180 	xc_one(dest->cpu_id, cbe_xcall_handler, (uint64_t)func, (uint64_t)farg);
181 	kpreempt_enable();
182 }
183 
184 /*ARGSUSED*/
185 static cyb_arg_t
186 cbe_configure(cpu_t *cpu)
187 {
188 	cbe_data_t *new_data = kmem_alloc(sizeof (cbe_data_t), KM_SLEEP);
189 
190 	/*
191 	 * The setsoftint() code will refuse to post a soft interrupt if
192 	 * one is already pending for the specified inum.  Given that we
193 	 * may have disjoint soft interrupts on different CPUs posted
194 	 * simultaneously, we allocate a new set of inums for each CPU.
195 	 */
196 	new_data->cbe_level10_inum = add_softintr(PIL_10,
197 	    (softintrfunc)cbe_level10, 0, SOFTINT_ST);
198 
199 	new_data->cbe_level1_inum = add_softintr(PIL_1,
200 	    (softintrfunc)cbe_level1, 0, SOFTINT_ST);
201 
202 	return (new_data);
203 }
204 
205 static void
206 cbe_unconfigure(cyb_arg_t arg)
207 {
208 	cbe_data_t *data = (cbe_data_t *)arg;
209 
210 	(void) rem_softintr(data->cbe_level10_inum);
211 	(void) rem_softintr(data->cbe_level1_inum);
212 
213 	kmem_free(data, sizeof (cbe_data_t));
214 }
215 
216 /*ARGSUSED*/
217 static void
218 cbe_suspend(cyb_arg_t arg)
219 {
220 	cbe_suspend_time = gethrtime_unscaled();
221 	cbe_suspend_delta = 0;
222 }
223 
224 /*ARGSUSED*/
225 static void
226 cbe_resume(cyb_arg_t arg)
227 {
228 	hrtime_t now;
229 
230 	/*
231 	 * If we're actually on a CPU which has apparently had %tick zeroed,
232 	 * we want to add cbe_suspend_delta to %tick.
233 	 */
234 	if ((now = gethrtime_unscaled()) < cbe_suspend_time) {
235 
236 		if (cbe_suspend_delta == 0) {
237 			/*
238 			 * We're the first CPU to be resumed.  We want %tick
239 			 * to be close to %tick when we suspended the system,
240 			 * so we'll figure out the delta which needs to be
241 			 * written to the register.  All subsequent resumed
242 			 * CPUs will write the same delta.
243 			 */
244 			cbe_suspend_delta = cbe_suspend_time - now;
245 		}
246 
247 		tick_write_delta(cbe_suspend_delta);
248 	}
249 }
250 
251 void
252 cbe_hres_tick(void)
253 {
254 	dtrace_hres_tick();
255 	hres_tick();
256 }
257 
258 void
259 cbe_init_pre(void)
260 {
261 	/* Nothing to do on sparc */
262 }
263 
264 void
265 cbe_init(void)
266 {
267 	cyc_handler_t hdlr;
268 	cyc_time_t when;
269 	hrtime_t resolution = NANOSEC / sys_tick_freq;
270 
271 	cyc_backend_t cbe = {
272 		cbe_configure,		/* cyb_configure */
273 		cbe_unconfigure,	/* cyb_unconfigure */
274 		cbe_enable,		/* cyb_enable */
275 		cbe_disable,		/* cyb_disable */
276 		cbe_reprogram,		/* cyb_reprogram */
277 		cbe_softint,		/* cyb_softint */
278 		cbe_set_level,		/* cyb_set_level */
279 		cbe_restore_level,	/* cyb_restore_level */
280 		cbe_xcall,		/* cyb_xcall */
281 		cbe_suspend,		/* cyb_suspend */
282 		cbe_resume		/* cyb_resume */
283 	};
284 
285 	cbe_level14_inum = add_softintr(CBE_HIGH_PIL,
286 	    (softintrfunc)cbe_level14, 0, SOFTINT_MT);
287 	cbe_hrtime_max = gethrtime_max();
288 
289 	/*
290 	 * If sys_tick_freq > NANOSEC (i.e. we're on a CPU with a clock rate
291 	 * which exceeds 1 GHz), we'll specify the minimum resolution,
292 	 * 1 nanosecond.
293 	 */
294 	if (resolution == 0)
295 		resolution = 1;
296 
297 	mutex_enter(&cpu_lock);
298 	cyclic_init(&cbe, resolution);
299 
300 	/*
301 	 * Initialize hrtime_base and hres_last_tick to reasonable starting
302 	 * values.
303 	 */
304 	hrtime_base = gethrtime();
305 	hres_last_tick = gethrtime_unscaled();
306 
307 	hdlr.cyh_level = CY_HIGH_LEVEL;
308 	hdlr.cyh_func = (cyc_func_t)cbe_hres_tick;
309 	hdlr.cyh_arg = NULL;
310 
311 	when.cyt_when = 0;
312 	when.cyt_interval = nsec_per_tick;
313 
314 	cbe_hres_cyclic = cyclic_add(&hdlr, &when);
315 
316 	mutex_exit(&cpu_lock);
317 
318 	clkstart();
319 }
320