1 /* $Id: at91pmc.c,v 1.8 2020/02/24 12:38:57 rin Exp $ */
2 /* $NetBSD: at91pmc.c,v 1.8 2020/02/24 12:38:57 rin Exp $ */
3
4 /*
5 * Copyright (c) 2007 Embedtronics Oy
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
19 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
21 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27 * POSSIBILITY OF SUCH DAMAGE.
28 */
29
30 #include <sys/cdefs.h>
31 __KERNEL_RCSID(0, "$NetBSD: at91pmc.c,v 1.8 2020/02/24 12:38:57 rin Exp $");
32
33 #include <sys/types.h>
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 #include <sys/time.h>
38 #include <sys/device.h>
39
40 #include <sys/bus.h>
41 #include <machine/intr.h>
42
43 #include <arm/cpufunc.h>
44
45 #include <arm/at91/at91reg.h>
46 #include <arm/at91/at91var.h>
47 #include <arm/at91/at91pmcreg.h>
48 #include <arm/at91/at91pmcvar.h>
49
50 #define SLOW_CLOCK 32768LU
51
52 void
at91pmc_get_clocks(struct at91bus_clocks * clocks)53 at91pmc_get_clocks(struct at91bus_clocks *clocks)
54 {
55 uint64_t mclk, pllaclk, pllbclk, pclk, mstclk;
56 uint32_t reg;
57
58 if (!((reg = PMCREG(PMC_MOR)) & PMC_MOR_MOSCEN))
59 panic("%s: main oscillator not enabled (MOR=%#X)", __FUNCTION__, reg);
60
61 if (!((reg = PMCREG(PMC_MCFR)) & PMC_MCFR_MAINRDY))
62 panic("%s: main oscillator not ready (MCFR=%#X)", __FUNCTION__, reg);
63
64 mclk = ((reg & PMC_MCFR_MAINF) * SLOW_CLOCK) / 16U;
65
66 // try to guess some nice MHz value
67 if (((mclk / 1000) % 1000) >= 990) {
68 mclk += 1000000U - (mclk % 1000000U);
69 } else if (((mclk / 1000) % 1000) <= 10) {
70 mclk -= (mclk % 1000000U);
71 }
72
73 PMCREG(PMC_PLLICPR) = PMC_PLLICPR_ICPPLLA | PMC_PLLICPR_ICPPLLB;
74
75 reg = PMCREG(PMC_PLLAR); pllaclk = 0;
76 if (reg & PMC_PLL_DIV) {
77 pllaclk = mclk * (((reg & PMC_PLL_MUL) >> PMC_PLL_MUL_SHIFT) + 1);
78 pllaclk /= (reg & PMC_PLL_DIV) >> PMC_PLL_DIV_SHIFT;
79 }
80
81 reg = PMCREG(PMC_PLLBR); pllbclk = 0;
82 if (reg & PMC_PLL_DIV) {
83 pllbclk = mclk * (((reg & PMC_PLL_MUL) >> PMC_PLL_MUL_SHIFT) + 1);
84 pllbclk /= (reg & PMC_PLL_DIV) >> PMC_PLL_DIV_SHIFT;
85 if (reg & PMC_PLLBR_USB_96M) {
86 pllbclk /= 2;
87 }
88 }
89
90 reg = PMCREG(PMC_MCKR);
91 switch ((reg & PMC_MCKR_CSS)) {
92 case PMC_MCKR_CSS_SLOW_CLK:
93 pclk = SLOW_CLOCK;
94 break;
95 default:
96 case PMC_MCKR_CSS_MAIN_CLK:
97 pclk = mclk;
98 break;
99 case PMC_MCKR_CSS_PLLA:
100 pclk = pllaclk;
101 break;
102 case PMC_MCKR_CSS_PLLB:
103 pclk = pllbclk;
104 break;
105 }
106 pclk >>= (reg & PMC_MCKR_PRES) >> PMC_MCKR_PRES_SHIFT;
107 mstclk = pclk / (((reg & PMC_MCKR_MDIV) >> PMC_MCKR_MDIV_SHIFT) + 1);
108
109 clocks->slow = SLOW_CLOCK;
110 clocks->main = mclk;
111 clocks->cpu = pclk;
112 clocks->master = mstclk;
113 clocks->plla = pllaclk;
114 clocks->pllb = pllbclk;
115 }
116
117
118 #define PID_COUNT 32
119 static int pid_enable_count[PID_COUNT] = {0};
120
121 void
at91pmc_peripheral_clock(int pid,int enable)122 at91pmc_peripheral_clock(int pid, int enable)
123 {
124 int s;
125
126 if (pid < 0 || pid >= PID_COUNT)
127 panic("%s: pid %d out of range", __FUNCTION__, pid);
128
129 s = splhigh();
130
131 if (enable) {
132 pid_enable_count[pid]++;
133 PMCREG(PMC_PCER) = (1U << pid);
134 } else {
135 if (--pid_enable_count[pid] < 0)
136 panic("%s: pid %d enable count got negative (%d)",
137 __FUNCTION__, pid, pid_enable_count[pid]);
138 if (pid_enable_count[pid] == 0)
139 PMCREG(PMC_PCDR) = (1U << pid);
140 }
141
142 splx(s);
143
144 if (enable) {
145 int c;
146 for (c = 0; c < 10000; c++) {
147 __insn_barrier();
148 }
149 }
150 }
151