xref: /openbmc/linux/arch/arm/mach-davinci/pm.c (revision 6c33a6f4)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * DaVinci Power Management Routines
4  *
5  * Copyright (C) 2009 Texas Instruments, Inc. http://www.ti.com/
6  */
7 
8 #include <linux/pm.h>
9 #include <linux/suspend.h>
10 #include <linux/module.h>
11 #include <linux/platform_device.h>
12 #include <linux/clk.h>
13 #include <linux/spinlock.h>
14 
15 #include <asm/cacheflush.h>
16 #include <asm/delay.h>
17 #include <asm/io.h>
18 
19 #include <mach/common.h>
20 #include <mach/da8xx.h>
21 #include <mach/mux.h>
22 #include <mach/pm.h>
23 
24 #include "clock.h"
25 #include "psc.h"
26 #include "sram.h"
27 
28 #define DA850_PLL1_BASE		0x01e1a000
29 #define DEEPSLEEP_SLEEPCOUNT_MASK	0xFFFF
30 #define DEEPSLEEP_SLEEPCOUNT		128
31 
32 static void (*davinci_sram_suspend) (struct davinci_pm_config *);
33 static struct davinci_pm_config pm_config = {
34 	.sleepcount = DEEPSLEEP_SLEEPCOUNT,
35 	.ddrpsc_num = DA8XX_LPSC1_EMIF3C,
36 };
37 
38 static void davinci_sram_push(void *dest, void *src, unsigned int size)
39 {
40 	memcpy(dest, src, size);
41 	flush_icache_range((unsigned long)dest, (unsigned long)(dest + size));
42 }
43 
44 static void davinci_pm_suspend(void)
45 {
46 	unsigned val;
47 
48 	if (pm_config.cpupll_reg_base != pm_config.ddrpll_reg_base) {
49 
50 		/* Switch CPU PLL to bypass mode */
51 		val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
52 		val &= ~(PLLCTL_PLLENSRC | PLLCTL_PLLEN);
53 		__raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
54 
55 		udelay(PLL_BYPASS_TIME);
56 
57 		/* Powerdown CPU PLL */
58 		val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
59 		val |= PLLCTL_PLLPWRDN;
60 		__raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
61 	}
62 
63 	/* Configure sleep count in deep sleep register */
64 	val = __raw_readl(pm_config.deepsleep_reg);
65 	val &= ~DEEPSLEEP_SLEEPCOUNT_MASK,
66 	val |= pm_config.sleepcount;
67 	__raw_writel(val, pm_config.deepsleep_reg);
68 
69 	/* System goes to sleep in this call */
70 	davinci_sram_suspend(&pm_config);
71 
72 	if (pm_config.cpupll_reg_base != pm_config.ddrpll_reg_base) {
73 
74 		/* put CPU PLL in reset */
75 		val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
76 		val &= ~PLLCTL_PLLRST;
77 		__raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
78 
79 		/* put CPU PLL in power down */
80 		val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
81 		val &= ~PLLCTL_PLLPWRDN;
82 		__raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
83 
84 		/* wait for CPU PLL reset */
85 		udelay(PLL_RESET_TIME);
86 
87 		/* bring CPU PLL out of reset */
88 		val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
89 		val |= PLLCTL_PLLRST;
90 		__raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
91 
92 		/* Wait for CPU PLL to lock */
93 		udelay(PLL_LOCK_TIME);
94 
95 		/* Remove CPU PLL from bypass mode */
96 		val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
97 		val &= ~PLLCTL_PLLENSRC;
98 		val |= PLLCTL_PLLEN;
99 		__raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
100 	}
101 }
102 
103 static int davinci_pm_enter(suspend_state_t state)
104 {
105 	int ret = 0;
106 
107 	switch (state) {
108 	case PM_SUSPEND_MEM:
109 		davinci_pm_suspend();
110 		break;
111 	default:
112 		ret = -EINVAL;
113 	}
114 
115 	return ret;
116 }
117 
118 static const struct platform_suspend_ops davinci_pm_ops = {
119 	.enter		= davinci_pm_enter,
120 	.valid		= suspend_valid_only_mem,
121 };
122 
123 int __init davinci_pm_init(void)
124 {
125 	int ret;
126 
127 	ret = davinci_cfg_reg(DA850_RTC_ALARM);
128 	if (ret)
129 		return ret;
130 
131 	pm_config.ddr2_ctlr_base = da8xx_get_mem_ctlr();
132 	pm_config.deepsleep_reg = DA8XX_SYSCFG1_VIRT(DA8XX_DEEPSLEEP_REG);
133 
134 	pm_config.cpupll_reg_base = ioremap(DA8XX_PLL0_BASE, SZ_4K);
135 	if (!pm_config.cpupll_reg_base)
136 		return -ENOMEM;
137 
138 	pm_config.ddrpll_reg_base = ioremap(DA850_PLL1_BASE, SZ_4K);
139 	if (!pm_config.ddrpll_reg_base) {
140 		ret = -ENOMEM;
141 		goto no_ddrpll_mem;
142 	}
143 
144 	pm_config.ddrpsc_reg_base = ioremap(DA8XX_PSC1_BASE, SZ_4K);
145 	if (!pm_config.ddrpsc_reg_base) {
146 		ret = -ENOMEM;
147 		goto no_ddrpsc_mem;
148 	}
149 
150 	davinci_sram_suspend = sram_alloc(davinci_cpu_suspend_sz, NULL);
151 	if (!davinci_sram_suspend) {
152 		pr_err("PM: cannot allocate SRAM memory\n");
153 		ret = -ENOMEM;
154 		goto no_sram_mem;
155 	}
156 
157 	davinci_sram_push(davinci_sram_suspend, davinci_cpu_suspend,
158 						davinci_cpu_suspend_sz);
159 
160 	suspend_set_ops(&davinci_pm_ops);
161 
162 	return 0;
163 
164 no_sram_mem:
165 	iounmap(pm_config.ddrpsc_reg_base);
166 no_ddrpsc_mem:
167 	iounmap(pm_config.ddrpll_reg_base);
168 no_ddrpll_mem:
169 	iounmap(pm_config.cpupll_reg_base);
170 	return ret;
171 }
172