xref: /openbmc/u-boot/arch/arm/mach-at91/clock.c (revision ee943655)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2015 Atmel Corporation
4  *		      Wenyou Yang <wenyou.yang@atmel.com>
5  */
6 
7 #include <common.h>
8 #include <asm/io.h>
9 #include <asm/arch/hardware.h>
10 #include <asm/arch/at91_pmc.h>
11 
12 #define EN_UPLL_TIMEOUT		500
13 
14 void at91_periph_clk_enable(int id)
15 {
16 	struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
17 
18 #ifdef CPU_HAS_PCR
19 	u32 regval;
20 	u32 div_value;
21 
22 	if (id > AT91_PMC_PCR_PID_MASK)
23 		return;
24 
25 	writel(id, &pmc->pcr);
26 
27 	div_value = readl(&pmc->pcr) & AT91_PMC_PCR_DIV;
28 
29 	regval = AT91_PMC_PCR_EN | AT91_PMC_PCR_CMD_WRITE | id | div_value;
30 
31 	writel(regval, &pmc->pcr);
32 #else
33 	writel(0x01 << id, &pmc->pcer);
34 #endif
35 }
36 
37 void at91_periph_clk_disable(int id)
38 {
39 	struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
40 
41 #ifdef CPU_HAS_PCR
42 	u32 regval;
43 
44 	if (id > AT91_PMC_PCR_PID_MASK)
45 		return;
46 
47 	regval = AT91_PMC_PCR_CMD_WRITE | id;
48 
49 	writel(regval, &pmc->pcr);
50 #else
51 	writel(0x01 << id, &pmc->pcdr);
52 #endif
53 }
54 
55 void at91_system_clk_enable(int sys_clk)
56 {
57 	struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
58 
59 	writel(sys_clk, &pmc->scer);
60 }
61 
62 void at91_system_clk_disable(int sys_clk)
63 {
64 	struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
65 
66 	writel(sys_clk, &pmc->scdr);
67 }
68 
69 int at91_upll_clk_enable(void)
70 {
71 	struct at91_pmc *pmc = (at91_pmc_t *)ATMEL_BASE_PMC;
72 	ulong start_time, tmp_time;
73 
74 	if ((readl(&pmc->uckr) & AT91_PMC_UPLLEN) == AT91_PMC_UPLLEN)
75 		return 0;
76 
77 	start_time = get_timer(0);
78 	writel(AT91_PMC_UPLLEN | AT91_PMC_BIASEN, &pmc->uckr);
79 	while ((readl(&pmc->sr) & AT91_PMC_LOCKU) != AT91_PMC_LOCKU) {
80 		tmp_time = get_timer(0);
81 		if ((tmp_time - start_time) > EN_UPLL_TIMEOUT) {
82 			printf("ERROR: failed to enable UPLL\n");
83 			return -1;
84 		}
85 	}
86 
87 	return 0;
88 }
89 
90 int at91_upll_clk_disable(void)
91 {
92 	struct at91_pmc *pmc = (at91_pmc_t *)ATMEL_BASE_PMC;
93 	ulong start_time, tmp_time;
94 
95 	start_time = get_timer(0);
96 	writel(readl(&pmc->uckr) & ~AT91_PMC_UPLLEN, &pmc->uckr);
97 	while ((readl(&pmc->sr) & AT91_PMC_LOCKU) == AT91_PMC_LOCKU) {
98 		tmp_time = get_timer(0);
99 		if ((tmp_time - start_time) > EN_UPLL_TIMEOUT) {
100 			printf("ERROR: failed to stop UPLL\n");
101 			return -1;
102 		}
103 	}
104 
105 	return 0;
106 }
107 
108 void at91_usb_clk_init(u32 value)
109 {
110 	struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
111 
112 	writel(value, &pmc->usb);
113 }
114 
115 void at91_pllicpr_init(u32 icpr)
116 {
117 	struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
118 
119 	writel(icpr, &pmc->pllicpr);
120 }
121