xref: /openbmc/linux/arch/arm/mach-omap2/prm2xxx.c (revision 1dd24dae)
1 /*
2  * OMAP2xxx PRM module functions
3  *
4  * Copyright (C) 2010-2012 Texas Instruments, Inc.
5  * Copyright (C) 2010 Nokia Corporation
6  * Benoît Cousson
7  * Paul Walmsley
8  * Rajendra Nayak <rnayak@ti.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  */
14 
15 #include <linux/kernel.h>
16 #include <linux/errno.h>
17 #include <linux/err.h>
18 #include <linux/io.h>
19 #include <linux/irq.h>
20 
21 #include "soc.h"
22 #include "common.h"
23 #include "vp.h"
24 #include "powerdomain.h"
25 #include "clockdomain.h"
26 #include "prm2xxx.h"
27 #include "cm2xxx_3xxx.h"
28 #include "prm-regbits-24xx.h"
29 
30 /*
31  * OMAP24xx PM_PWSTCTRL_*.POWERSTATE and PM_PWSTST_*.LASTSTATEENTERED bits -
32  * these are reversed from the bits used on OMAP3+
33  */
34 #define OMAP24XX_PWRDM_POWER_ON			0x0
35 #define OMAP24XX_PWRDM_POWER_RET		0x1
36 #define OMAP24XX_PWRDM_POWER_OFF		0x3
37 
38 /*
39  * omap2xxx_prm_reset_src_map - map from bits in the PRM_RSTST_WKUP
40  *   hardware register (which are specific to the OMAP2xxx SoCs) to
41  *   reset source ID bit shifts (which is an OMAP SoC-independent
42  *   enumeration)
43  */
44 static struct prm_reset_src_map omap2xxx_prm_reset_src_map[] = {
45 	{ OMAP_GLOBALCOLD_RST_SHIFT, OMAP_GLOBAL_COLD_RST_SRC_ID_SHIFT },
46 	{ OMAP_GLOBALWARM_RST_SHIFT, OMAP_GLOBAL_WARM_RST_SRC_ID_SHIFT },
47 	{ OMAP24XX_SECU_VIOL_RST_SHIFT, OMAP_SECU_VIOL_RST_SRC_ID_SHIFT },
48 	{ OMAP24XX_MPU_WD_RST_SHIFT, OMAP_MPU_WD_RST_SRC_ID_SHIFT },
49 	{ OMAP24XX_SECU_WD_RST_SHIFT, OMAP_SECU_WD_RST_SRC_ID_SHIFT },
50 	{ OMAP24XX_EXTWMPU_RST_SHIFT, OMAP_EXTWARM_RST_SRC_ID_SHIFT },
51 	{ -1, -1 },
52 };
53 
54 /**
55  * omap2xxx_prm_read_reset_sources - return the last SoC reset source
56  *
57  * Return a u32 representing the last reset sources of the SoC.  The
58  * returned reset source bits are standardized across OMAP SoCs.
59  */
60 static u32 omap2xxx_prm_read_reset_sources(void)
61 {
62 	struct prm_reset_src_map *p;
63 	u32 r = 0;
64 	u32 v;
65 
66 	v = omap2_prm_read_mod_reg(WKUP_MOD, OMAP2_RM_RSTST);
67 
68 	p = omap2xxx_prm_reset_src_map;
69 	while (p->reg_shift >= 0 && p->std_shift >= 0) {
70 		if (v & (1 << p->reg_shift))
71 			r |= 1 << p->std_shift;
72 		p++;
73 	}
74 
75 	return r;
76 }
77 
78 /**
79  * omap2xxx_pwrst_to_common_pwrst - convert OMAP2xxx pwrst to common pwrst
80  * @omap2xxx_pwrst: OMAP2xxx hardware power state to convert
81  *
82  * Return the common power state bits corresponding to the OMAP2xxx
83  * hardware power state bits @omap2xxx_pwrst, or -EINVAL upon error.
84  */
85 static int omap2xxx_pwrst_to_common_pwrst(u8 omap2xxx_pwrst)
86 {
87 	u8 pwrst;
88 
89 	switch (omap2xxx_pwrst) {
90 	case OMAP24XX_PWRDM_POWER_OFF:
91 		pwrst = PWRDM_POWER_OFF;
92 		break;
93 	case OMAP24XX_PWRDM_POWER_RET:
94 		pwrst = PWRDM_POWER_RET;
95 		break;
96 	case OMAP24XX_PWRDM_POWER_ON:
97 		pwrst = PWRDM_POWER_ON;
98 		break;
99 	default:
100 		return -EINVAL;
101 	}
102 
103 	return pwrst;
104 }
105 
106 /**
107  * omap2xxx_prm_dpll_reset - use DPLL reset to reboot the OMAP SoC
108  *
109  * Set the DPLL reset bit, which should reboot the SoC.  This is the
110  * recommended way to restart the SoC.  No return value.
111  */
112 void omap2xxx_prm_dpll_reset(void)
113 {
114 	omap2_prm_set_mod_reg_bits(OMAP_RST_DPLL3_MASK, WKUP_MOD,
115 				   OMAP2_RM_RSTCTRL);
116 	/* OCP barrier */
117 	omap2_prm_read_mod_reg(WKUP_MOD, OMAP2_RM_RSTCTRL);
118 }
119 
120 int omap2xxx_clkdm_sleep(struct clockdomain *clkdm)
121 {
122 	omap2_prm_set_mod_reg_bits(OMAP24XX_FORCESTATE_MASK,
123 				   clkdm->pwrdm.ptr->prcm_offs,
124 				   OMAP2_PM_PWSTCTRL);
125 	return 0;
126 }
127 
128 int omap2xxx_clkdm_wakeup(struct clockdomain *clkdm)
129 {
130 	omap2_prm_clear_mod_reg_bits(OMAP24XX_FORCESTATE_MASK,
131 				     clkdm->pwrdm.ptr->prcm_offs,
132 				     OMAP2_PM_PWSTCTRL);
133 	return 0;
134 }
135 
136 static int omap2xxx_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
137 {
138 	u8 omap24xx_pwrst;
139 
140 	switch (pwrst) {
141 	case PWRDM_POWER_OFF:
142 		omap24xx_pwrst = OMAP24XX_PWRDM_POWER_OFF;
143 		break;
144 	case PWRDM_POWER_RET:
145 		omap24xx_pwrst = OMAP24XX_PWRDM_POWER_RET;
146 		break;
147 	case PWRDM_POWER_ON:
148 		omap24xx_pwrst = OMAP24XX_PWRDM_POWER_ON;
149 		break;
150 	default:
151 		return -EINVAL;
152 	}
153 
154 	omap2_prm_rmw_mod_reg_bits(OMAP_POWERSTATE_MASK,
155 				   (omap24xx_pwrst << OMAP_POWERSTATE_SHIFT),
156 				   pwrdm->prcm_offs, OMAP2_PM_PWSTCTRL);
157 	return 0;
158 }
159 
160 static int omap2xxx_pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
161 {
162 	u8 omap2xxx_pwrst;
163 
164 	omap2xxx_pwrst = omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
165 						       OMAP2_PM_PWSTCTRL,
166 						       OMAP_POWERSTATE_MASK);
167 
168 	return omap2xxx_pwrst_to_common_pwrst(omap2xxx_pwrst);
169 }
170 
171 static int omap2xxx_pwrdm_read_pwrst(struct powerdomain *pwrdm)
172 {
173 	u8 omap2xxx_pwrst;
174 
175 	omap2xxx_pwrst = omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
176 						       OMAP2_PM_PWSTST,
177 						       OMAP_POWERSTATEST_MASK);
178 
179 	return omap2xxx_pwrst_to_common_pwrst(omap2xxx_pwrst);
180 }
181 
182 struct pwrdm_ops omap2_pwrdm_operations = {
183 	.pwrdm_set_next_pwrst	= omap2xxx_pwrdm_set_next_pwrst,
184 	.pwrdm_read_next_pwrst	= omap2xxx_pwrdm_read_next_pwrst,
185 	.pwrdm_read_pwrst	= omap2xxx_pwrdm_read_pwrst,
186 	.pwrdm_set_logic_retst	= omap2_pwrdm_set_logic_retst,
187 	.pwrdm_set_mem_onst	= omap2_pwrdm_set_mem_onst,
188 	.pwrdm_set_mem_retst	= omap2_pwrdm_set_mem_retst,
189 	.pwrdm_read_mem_pwrst	= omap2_pwrdm_read_mem_pwrst,
190 	.pwrdm_read_mem_retst	= omap2_pwrdm_read_mem_retst,
191 	.pwrdm_wait_transition	= omap2_pwrdm_wait_transition,
192 };
193 
194 /*
195  *
196  */
197 
198 static struct prm_ll_data omap2xxx_prm_ll_data = {
199 	.read_reset_sources = &omap2xxx_prm_read_reset_sources,
200 };
201 
202 int __init omap2xxx_prm_init(void)
203 {
204 	if (!cpu_is_omap24xx())
205 		return 0;
206 
207 	return prm_register(&omap2xxx_prm_ll_data);
208 }
209 
210 static void __exit omap2xxx_prm_exit(void)
211 {
212 	if (!cpu_is_omap24xx())
213 		return;
214 
215 	/* Should never happen */
216 	WARN(prm_unregister(&omap2xxx_prm_ll_data),
217 	     "%s: prm_ll_data function pointer mismatch\n", __func__);
218 }
219 __exitcall(omap2xxx_prm_exit);
220