clock.c revision 1.5 1 /* $NetBSD: clock.c,v 1.5 2014/12/31 15:25:08 martin Exp $ */
2
3 /*-
4 * Copyright (c) 2014 Michael Lorenz
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: clock.c,v 1.5 2014/12/31 15:25:08 martin Exp $");
31
32 #include <sys/param.h>
33 #include <sys/cpu.h>
34 #include <sys/device.h>
35 #include <sys/kernel.h>
36 #include <sys/systm.h>
37 #include <sys/timetc.h>
38
39 #include <mips/ingenic/ingenic_regs.h>
40
41 #include "opt_ingenic.h"
42
43 extern void ingenic_puts(const char *);
44
45 void ingenic_clockintr(uint32_t);
46
47 static u_int
48 ingenic_count_read(struct timecounter *tc)
49 {
50 return readreg(JZ_OST_CNT_LO);
51 }
52
53 void
54 cpu_initclocks(void)
55 {
56 struct cpu_info * const ci = curcpu();
57 uint32_t cnt;
58
59 static struct timecounter tc = {
60 ingenic_count_read, /* get_timecount */
61 0, /* no poll_pps */
62 ~0u, /* counter_mask */
63 12000000, /* frequency */
64 "Ingenic OS timer", /* name */
65 100, /* quality */
66 };
67
68 curcpu()->ci_cctr_freq = tc.tc_frequency;
69
70 tc_init(&tc);
71
72 printf("starting timer interrupt...\n");
73 /* start the timer interrupt */
74 cnt = readreg(JZ_OST_CNT_LO);
75 ci->ci_next_cp0_clk_intr = cnt + ci->ci_cycles_per_hz;
76 writereg(JZ_TC_TFCR, TFR_OSTFLAG);
77 writereg(JZ_OST_DATA, ci->ci_next_cp0_clk_intr);
78 /*
79 * XXX
80 * We can use OST or one of the regular timers to generate the 100hz
81 * interrupt. OST interrupts need to be rescheduled every time and by
82 * only one core, the regular timer can be programmed to fire every
83 * 10ms without rescheduling and we'd still use the OST as time base.
84 * OST is supposed to fire on INT2 although I haven't been able to get
85 * that to work yet ( all I get is INT0 which is for hardware interrupts
86 * in general )
87 * So if we can get OST to fire on INT2 we can just block INT0 on core1
88 * and have a timer interrupt on both cores, if not the regular timer
89 * would be more convenient but we'd have to shoot an IPI to core1 on
90 * every tick.
91 * For now, use OST and hope we'll figure out how to make it fire on
92 * INT2.
93 */
94 #ifdef USE_OST
95 writereg(JZ_TC_TMCR, TFR_OSTFLAG);
96 #else
97 writereg(JZ_TC_TECR, TESR_TCST5); /* disable timer 5 */
98 writereg(JZ_TC_TCNT(5), 0);
99 writereg(JZ_TC_TDFR(5), 30000); /* 10ms at 48MHz / 16 */
100 writereg(JZ_TC_TDHR(5), 60000); /* not reached */
101 writereg(JZ_TC_TCSR(5), TCSR_EXT_EN| TCSR_DIV_16);
102 writereg(JZ_TC_TMCR, TFR_FFLAG5);
103 writereg(JZ_TC_TFCR, TFR_FFLAG5);
104 writereg(JZ_TC_TESR, TESR_TCST5); /* enable timer 5 */
105 #endif
106
107 #ifdef INGENIC_CLOCK_DEBUG
108 printf("INTC %08x %08x\n", readreg(JZ_ICSR0), readreg(JZ_ICSR1));
109 printf("ICMR0 %08x\n", readreg(JZ_ICMR0));
110 #endif
111 writereg(JZ_ICMCR0, 0x0c000000); /* TCU2, OST */
112 spl0();
113 #ifdef INGENIC_CLOCK_DEBUG
114 printf("TFR: %08x\n", readreg(JZ_TC_TFR));
115 printf("TMR: %08x\n", readreg(JZ_TC_TMR));
116 printf("cnt5: %08x\n", readreg(JZ_TC_TCNT(5)));
117 printf("CR: %08x\n", MFC0(MIPS_COP_0_CAUSE, 0));
118 printf("SR: %08x\n", MFC0(MIPS_COP_0_STATUS, 0));
119 delay(100000);
120 printf("TFR: %08x\n", readreg(JZ_TC_TFR));
121 printf("TMR: %08x\n", readreg(JZ_TC_TMR));
122 printf("cnt5: %08x\n", readreg(JZ_TC_TCNT(5)));
123 printf("CR: %08x\n", MFC0(MIPS_COP_0_CAUSE, 0));
124 printf("SR: %08x\n", MFC0(MIPS_COP_0_STATUS, 0));
125 printf("TFR: %08x\n", readreg(JZ_TC_TFR));
126 printf("TMR: %08x\n", readreg(JZ_TC_TMR));
127 printf("cnt5: %08x\n", readreg(JZ_TC_TCNT(5)));
128 printf("CR: %08x\n", MFC0(MIPS_COP_0_CAUSE, 0));
129 printf("SR: %08x\n", MFC0(MIPS_COP_0_STATUS, 0));
130
131 printf("INTC %08x %08x\n", readreg(JZ_ICSR0), readreg(JZ_ICSR1));
132 delay(3000000);
133 #endif
134 }
135
136 /* shamelessly stolen from mips3_clock.c */
137 void
138 delay(int n)
139 {
140 u_long divisor_delay;
141 uint32_t cur, last, delta, usecs;
142
143 last = readreg(JZ_OST_CNT_LO);
144 delta = usecs = 0;
145
146 divisor_delay = curcpu()->ci_divisor_delay;
147 if (divisor_delay == 0) {
148 /*
149 * Frequency values in curcpu() are not initialized.
150 * Assume faster frequency since longer delays are harmless.
151 * Note CPU_MIPS_DOUBLE_COUNT is ignored here.
152 */
153 #define FAST_FREQ (300 * 1000 * 1000) /* fast enough? */
154 divisor_delay = FAST_FREQ / (1000 * 1000);
155 }
156 while (n > usecs) {
157 cur = readreg(JZ_OST_CNT_LO);
158
159 /*
160 * We setup the OS timer to always counts upto UINT32_MAX,
161 * so no need to check wrapped around case.
162 */
163 delta += (cur - last);
164
165 last = cur;
166
167 while (delta >= divisor_delay) {
168 /*
169 * delta is not so larger than divisor_delay here,
170 * and using DIV/DIVU ops could be much slower.
171 * (though longer delay may be harmless)
172 */
173 usecs++;
174 delta -= divisor_delay;
175 }
176 }
177 }
178
179 void
180 setstatclockrate(int r)
181 {
182 /* we could just use another timer channel here */
183 }
184
185 #ifdef INGENIC_CLOCK_DEBUG
186 int cnt = 99;
187 #endif
188
189 void
190 ingenic_clockintr(uint32_t id)
191 {
192 extern struct clockframe cf;
193 struct cpu_info * const ci = curcpu();
194 #ifdef USE_OST
195 uint32_t new_cnt;
196 #endif
197 ci->ci_ev_count_compare.ev_count++;
198
199 /* clear flags */
200 writereg(JZ_TC_TFCR, TFR_OSTFLAG);
201
202 KASSERT((ci->ci_cycles_per_hz & ~(0xffffffff)) == 0);
203 ci->ci_next_cp0_clk_intr += (uint32_t)(ci->ci_cycles_per_hz & 0xffffffff);
204 #ifdef USE_OST
205 writereg(JZ_OST_DATA, ci->ci_next_cp0_clk_intr);
206
207 /* Check for lost clock interrupts */
208 new_cnt = readreg(JZ_OST_CNT_LO);
209
210 /*
211 * Missed one or more clock interrupts, so let's start
212 * counting again from the current value.
213 */
214 if ((ci->ci_next_cp0_clk_intr - new_cnt) & 0x80000000) {
215
216 ci->ci_next_cp0_clk_intr = new_cnt + curcpu()->ci_cycles_per_hz;
217 writereg(JZ_OST_DATA, ci->ci_next_cp0_clk_intr);
218 curcpu()->ci_ev_count_compare_missed.ev_count++;
219 }
220 writereg(JZ_TC_TFCR, TFR_OSTFLAG);
221 #else
222 writereg(JZ_TC_TFCR, TFR_FFLAG5);
223 #endif
224
225 #ifdef INGENIC_CLOCK_DEBUG
226 cnt++;
227 if (cnt == 100) {
228 cnt = 0;
229 ingenic_puts("+");
230 }
231 #endif
232 hardclock(&cf);
233 }
234