blob: 76fcada788a44be50cd6d6f0cc1181dbd2f37596 [file] [log] [blame]
Bo Shen3225f342013-05-12 22:40:54 +00001/*
2 * [origin: Linux kernel linux/arch/arm/mach-at91/clock.c]
3 *
4 * Copyright (C) 2005 David Brownell
5 * Copyright (C) 2005 Ivan Kokshaysky
6 * Copyright (C) 2009 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
7 * Copyright (C) 2013 Bo Shen <voice.shen@atmel.com>
Wenyou Yangc1900052015-10-30 09:47:02 +08008 * Copyright (C) 2015 Wenyou Yang <wenyou.yang@atmel.com>
Bo Shen3225f342013-05-12 22:40:54 +00009 *
Wolfgang Denk1a459662013-07-08 09:37:19 +020010 * SPDX-License-Identifier: GPL-2.0+
Bo Shen3225f342013-05-12 22:40:54 +000011 */
12
13#include <common.h>
Wenyou Yangc1900052015-10-30 09:47:02 +080014#include <asm/errno.h>
Bo Shen3225f342013-05-12 22:40:54 +000015#include <asm/io.h>
16#include <asm/arch/hardware.h>
17#include <asm/arch/at91_pmc.h>
18#include <asm/arch/clk.h>
19
20#if !defined(CONFIG_AT91FAMILY)
21# error You need to define CONFIG_AT91FAMILY in your board config!
22#endif
23
24DECLARE_GLOBAL_DATA_PTR;
25
26static unsigned long at91_css_to_rate(unsigned long css)
27{
28 switch (css) {
29 case AT91_PMC_MCKR_CSS_SLOW:
30 return CONFIG_SYS_AT91_SLOW_CLOCK;
31 case AT91_PMC_MCKR_CSS_MAIN:
32 return gd->arch.main_clk_rate_hz;
33 case AT91_PMC_MCKR_CSS_PLLA:
34 return gd->arch.plla_rate_hz;
35 }
36
37 return 0;
38}
39
40static u32 at91_pll_rate(u32 freq, u32 reg)
41{
42 unsigned mul, div;
43
44 div = reg & 0xff;
45 mul = (reg >> 18) & 0x7f;
46 if (div && mul) {
47 freq /= div;
48 freq *= mul + 1;
49 } else {
50 freq = 0;
51 }
52
53 return freq;
54}
55
56int at91_clock_init(unsigned long main_clock)
57{
58 unsigned freq, mckr;
59 struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
60#ifndef CONFIG_SYS_AT91_MAIN_CLOCK
61 unsigned tmp;
62 /*
63 * When the bootloader initialized the main oscillator correctly,
64 * there's no problem using the cycle counter. But if it didn't,
65 * or when using oscillator bypass mode, we must be told the speed
66 * of the main clock.
67 */
68 if (!main_clock) {
69 do {
70 tmp = readl(&pmc->mcfr);
71 } while (!(tmp & AT91_PMC_MCFR_MAINRDY));
72 tmp &= AT91_PMC_MCFR_MAINF_MASK;
73 main_clock = tmp * (CONFIG_SYS_AT91_SLOW_CLOCK / 16);
74 }
75#endif
76 gd->arch.main_clk_rate_hz = main_clock;
77
78 /* report if PLLA is more than mildly overclocked */
79 gd->arch.plla_rate_hz = at91_pll_rate(main_clock, readl(&pmc->pllar));
80
81 /*
82 * MCK and CPU derive from one of those primary clocks.
83 * For now, assume this parentage won't change.
84 */
85 mckr = readl(&pmc->mckr);
86
87 /* plla divisor by 2 */
88 if (mckr & (1 << 12))
89 gd->arch.plla_rate_hz >>= 1;
90
91 gd->arch.mck_rate_hz = at91_css_to_rate(mckr & AT91_PMC_MCKR_CSS_MASK);
92 freq = gd->arch.mck_rate_hz;
93
94 /* prescale */
95 freq >>= mckr & AT91_PMC_MCKR_PRES_MASK;
96
97 switch (mckr & AT91_PMC_MCKR_MDIV_MASK) {
98 case AT91_PMC_MCKR_MDIV_2:
99 gd->arch.mck_rate_hz = freq / 2;
100 break;
101 case AT91_PMC_MCKR_MDIV_3:
102 gd->arch.mck_rate_hz = freq / 3;
103 break;
104 case AT91_PMC_MCKR_MDIV_4:
105 gd->arch.mck_rate_hz = freq / 4;
106 break;
107 default:
108 break;
109 }
110
111 gd->arch.cpu_clk_rate_hz = freq;
112
113 return 0;
114}
115
Heiko Schocher5abc00d2014-10-31 08:31:04 +0100116void at91_plla_init(u32 pllar)
117{
118 struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
119
120 writel(pllar, &pmc->pllar);
121 while (!(readl(&pmc->sr) & (AT91_PMC_LOCKA | AT91_PMC_MCKRDY)))
122 ;
123}
124
125void at91_mck_init(u32 mckr)
126{
127 struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
128 u32 tmp;
129
130 tmp = readl(&pmc->mckr);
131 tmp &= ~(AT91_PMC_MCKR_CSS_MASK |
132 AT91_PMC_MCKR_PRES_MASK |
133 AT91_PMC_MCKR_MDIV_MASK |
134 AT91_PMC_MCKR_PLLADIV_2);
Bo Shen05084442014-12-15 13:24:27 +0800135#ifdef CPU_HAS_H32MXDIV
136 tmp &= ~AT91_PMC_MCKR_H32MXDIV;
137#endif
138
Heiko Schocher5abc00d2014-10-31 08:31:04 +0100139 tmp |= mckr & (AT91_PMC_MCKR_CSS_MASK |
140 AT91_PMC_MCKR_PRES_MASK |
141 AT91_PMC_MCKR_MDIV_MASK |
142 AT91_PMC_MCKR_PLLADIV_2);
Bo Shen05084442014-12-15 13:24:27 +0800143#ifdef CPU_HAS_H32MXDIV
144 tmp |= mckr & AT91_PMC_MCKR_H32MXDIV;
145#endif
146
Heiko Schocher5abc00d2014-10-31 08:31:04 +0100147 writel(tmp, &pmc->mckr);
148
149 while (!(readl(&pmc->sr) & AT91_PMC_MCKRDY))
150 ;
151}
152
Wenyou Yangc1900052015-10-30 09:47:02 +0800153int at91_enable_periph_generated_clk(u32 id, u32 clk_source, u32 div)
154{
155 struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
156 u32 regval, status;
157 u32 timeout = 1000;
158
159 if (id > AT91_PMC_PCR_PID_MASK)
160 return -EINVAL;
161
162 if (div > 0xff)
163 return -EINVAL;
164
Wenyou Yang4adf6a72016-04-11 16:41:31 +0800165 if (clk_source == GCK_CSS_UPLL_CLK) {
166 if (at91_upll_clk_enable())
167 return -ENODEV;
168 }
169
Wenyou Yangc1900052015-10-30 09:47:02 +0800170 writel(id, &pmc->pcr);
171 regval = readl(&pmc->pcr);
172 regval &= ~AT91_PMC_PCR_GCKCSS;
173 regval &= ~AT91_PMC_PCR_GCKDIV;
174
175 switch (clk_source) {
176 case GCK_CSS_SLOW_CLK:
177 regval |= AT91_PMC_PCR_GCKCSS_SLOW_CLK;
178 break;
179 case GCK_CSS_MAIN_CLK:
180 regval |= AT91_PMC_PCR_GCKCSS_MAIN_CLK;
181 break;
182 case GCK_CSS_PLLA_CLK:
183 regval |= AT91_PMC_PCR_GCKCSS_PLLA_CLK;
184 break;
185 case GCK_CSS_UPLL_CLK:
186 regval |= AT91_PMC_PCR_GCKCSS_UPLL_CLK;
187 break;
188 case GCK_CSS_MCK_CLK:
189 regval |= AT91_PMC_PCR_GCKCSS_MCK_CLK;
190 break;
191 case GCK_CSS_AUDIO_CLK:
192 regval |= AT91_PMC_PCR_GCKCSS_AUDIO_CLK;
193 break;
194 default:
195 printf("Error GCK clock source selection!\n");
196 return -EINVAL;
197 }
198
199 regval |= AT91_PMC_PCR_CMD_WRITE |
200 AT91_PMC_PCR_GCKDIV_(div) |
201 AT91_PMC_PCR_GCKEN;
202
203 writel(regval, &pmc->pcr);
204
205 do {
206 udelay(1);
207 status = readl(&pmc->sr);
208 } while ((!!(--timeout)) && (!(status & AT91_PMC_GCKRDY)));
209
210 if (!timeout)
211 printf("Timeout waiting for GCK ready!\n");
212
213 return 0;
214}
215
216u32 at91_get_periph_generated_clk(u32 id)
217{
218 struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
219 u32 regval, clk_source, div;
220 u32 freq;
221
222 if (id > AT91_PMC_PCR_PID_MASK)
223 return 0;
224
225 writel(id, &pmc->pcr);
226 regval = readl(&pmc->pcr);
227
228 clk_source = regval & AT91_PMC_PCR_GCKCSS;
229 switch (clk_source) {
230 case AT91_PMC_PCR_GCKCSS_SLOW_CLK:
231 freq = CONFIG_SYS_AT91_SLOW_CLOCK;
232 break;
233 case AT91_PMC_PCR_GCKCSS_MAIN_CLK:
234 freq = gd->arch.main_clk_rate_hz;
235 break;
236 case AT91_PMC_PCR_GCKCSS_PLLA_CLK:
237 freq = gd->arch.plla_rate_hz;
238 break;
Wenyou Yang7a91e1a2016-04-11 16:41:32 +0800239 case AT91_PMC_PCR_GCKCSS_UPLL_CLK:
240 freq = AT91_UTMI_PLL_CLK_FREQ;
241 break;
242 case AT91_PMC_PCR_GCKCSS_MCK_CLK:
243 freq = gd->arch.mck_rate_hz;
244 break;
Wenyou Yangc1900052015-10-30 09:47:02 +0800245 default:
246 printf("Improper GCK clock source selection!\n");
247 freq = 0;
248 break;
249 }
250
251 div = ((regval & AT91_PMC_PCR_GCKDIV) >> AT91_PMC_PCR_GCKDIV_OFFSET);
252 div += 1;
253
254 return freq / div;
255}