xref: /linux/arch/arm/mach-davinci/pm.c (revision 7aacf86b75bc5523d20fd9127104384fce51ce9c)
1 /*
2  * DaVinci Power Management Routines
3  *
4  * Copyright (C) 2009 Texas Instruments, Inc. http://www.ti.com/
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 
11 #include <linux/pm.h>
12 #include <linux/suspend.h>
13 #include <linux/module.h>
14 #include <linux/platform_device.h>
15 #include <linux/clk.h>
16 #include <linux/spinlock.h>
17 
18 #include <asm/cacheflush.h>
19 #include <asm/delay.h>
20 #include <asm/io.h>
21 
22 #include <mach/common.h>
23 #include <mach/da8xx.h>
24 #include <mach/mux.h>
25 #include <mach/pm.h>
26 
27 #include "clock.h"
28 #include "psc.h"
29 #include "sram.h"
30 
31 #define DA850_PLL1_BASE		0x01e1a000
32 #define DEEPSLEEP_SLEEPCOUNT_MASK	0xFFFF
33 #define DEEPSLEEP_SLEEPCOUNT		128
34 
35 static void (*davinci_sram_suspend) (struct davinci_pm_config *);
36 static struct davinci_pm_config pm_config = {
37 	.sleepcount = DEEPSLEEP_SLEEPCOUNT,
38 	.ddrpsc_num = DA8XX_LPSC1_EMIF3C,
39 };
40 
41 static void davinci_sram_push(void *dest, void *src, unsigned int size)
42 {
43 	memcpy(dest, src, size);
44 	flush_icache_range((unsigned long)dest, (unsigned long)(dest + size));
45 }
46 
47 static void davinci_pm_suspend(void)
48 {
49 	unsigned val;
50 
51 	if (pm_config.cpupll_reg_base != pm_config.ddrpll_reg_base) {
52 
53 		/* Switch CPU PLL to bypass mode */
54 		val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
55 		val &= ~(PLLCTL_PLLENSRC | PLLCTL_PLLEN);
56 		__raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
57 
58 		udelay(PLL_BYPASS_TIME);
59 
60 		/* Powerdown CPU PLL */
61 		val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
62 		val |= PLLCTL_PLLPWRDN;
63 		__raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
64 	}
65 
66 	/* Configure sleep count in deep sleep register */
67 	val = __raw_readl(pm_config.deepsleep_reg);
68 	val &= ~DEEPSLEEP_SLEEPCOUNT_MASK,
69 	val |= pm_config.sleepcount;
70 	__raw_writel(val, pm_config.deepsleep_reg);
71 
72 	/* System goes to sleep in this call */
73 	davinci_sram_suspend(&pm_config);
74 
75 	if (pm_config.cpupll_reg_base != pm_config.ddrpll_reg_base) {
76 
77 		/* put CPU PLL in reset */
78 		val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
79 		val &= ~PLLCTL_PLLRST;
80 		__raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
81 
82 		/* put CPU PLL in power down */
83 		val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
84 		val &= ~PLLCTL_PLLPWRDN;
85 		__raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
86 
87 		/* wait for CPU PLL reset */
88 		udelay(PLL_RESET_TIME);
89 
90 		/* bring CPU PLL out of reset */
91 		val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
92 		val |= PLLCTL_PLLRST;
93 		__raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
94 
95 		/* Wait for CPU PLL to lock */
96 		udelay(PLL_LOCK_TIME);
97 
98 		/* Remove CPU PLL from bypass mode */
99 		val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
100 		val &= ~PLLCTL_PLLENSRC;
101 		val |= PLLCTL_PLLEN;
102 		__raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
103 	}
104 }
105 
106 static int davinci_pm_enter(suspend_state_t state)
107 {
108 	int ret = 0;
109 
110 	switch (state) {
111 	case PM_SUSPEND_MEM:
112 		davinci_pm_suspend();
113 		break;
114 	default:
115 		ret = -EINVAL;
116 	}
117 
118 	return ret;
119 }
120 
121 static const struct platform_suspend_ops davinci_pm_ops = {
122 	.enter		= davinci_pm_enter,
123 	.valid		= suspend_valid_only_mem,
124 };
125 
126 int __init davinci_pm_init(void)
127 {
128 	int ret;
129 
130 	ret = davinci_cfg_reg(DA850_RTC_ALARM);
131 	if (ret)
132 		return ret;
133 
134 	pm_config.ddr2_ctlr_base = da8xx_get_mem_ctlr();
135 	pm_config.deepsleep_reg = DA8XX_SYSCFG1_VIRT(DA8XX_DEEPSLEEP_REG);
136 
137 	pm_config.cpupll_reg_base = ioremap(DA8XX_PLL0_BASE, SZ_4K);
138 	if (!pm_config.cpupll_reg_base)
139 		return -ENOMEM;
140 
141 	pm_config.ddrpll_reg_base = ioremap(DA850_PLL1_BASE, SZ_4K);
142 	if (!pm_config.ddrpll_reg_base) {
143 		ret = -ENOMEM;
144 		goto no_ddrpll_mem;
145 	}
146 
147 	pm_config.ddrpsc_reg_base = ioremap(DA8XX_PSC1_BASE, SZ_4K);
148 	if (!pm_config.ddrpsc_reg_base) {
149 		ret = -ENOMEM;
150 		goto no_ddrpsc_mem;
151 	}
152 
153 	davinci_sram_suspend = sram_alloc(davinci_cpu_suspend_sz, NULL);
154 	if (!davinci_sram_suspend) {
155 		pr_err("PM: cannot allocate SRAM memory\n");
156 		ret = -ENOMEM;
157 		goto no_sram_mem;
158 	}
159 
160 	davinci_sram_push(davinci_sram_suspend, davinci_cpu_suspend,
161 						davinci_cpu_suspend_sz);
162 
163 	suspend_set_ops(&davinci_pm_ops);
164 
165 	return 0;
166 
167 no_sram_mem:
168 	iounmap(pm_config.ddrpsc_reg_base);
169 no_ddrpsc_mem:
170 	iounmap(pm_config.ddrpll_reg_base);
171 no_ddrpll_mem:
172 	iounmap(pm_config.cpupll_reg_base);
173 	return ret;
174 }
175