xref: /openbmc/linux/arch/arm/mach-omap2/prm2xxx.c (revision 9cfc5c90)
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 "powerdomain.h"
22 #include "clockdomain.h"
23 #include "prm2xxx.h"
24 #include "cm2xxx_3xxx.h"
25 #include "prm-regbits-24xx.h"
26 
27 /*
28  * OMAP24xx PM_PWSTCTRL_*.POWERSTATE and PM_PWSTST_*.LASTSTATEENTERED bits -
29  * these are reversed from the bits used on OMAP3+
30  */
31 #define OMAP24XX_PWRDM_POWER_ON			0x0
32 #define OMAP24XX_PWRDM_POWER_RET		0x1
33 #define OMAP24XX_PWRDM_POWER_OFF		0x3
34 
35 /*
36  * omap2xxx_prm_reset_src_map - map from bits in the PRM_RSTST_WKUP
37  *   hardware register (which are specific to the OMAP2xxx SoCs) to
38  *   reset source ID bit shifts (which is an OMAP SoC-independent
39  *   enumeration)
40  */
41 static struct prm_reset_src_map omap2xxx_prm_reset_src_map[] = {
42 	{ OMAP_GLOBALCOLD_RST_SHIFT, OMAP_GLOBAL_COLD_RST_SRC_ID_SHIFT },
43 	{ OMAP_GLOBALWARM_RST_SHIFT, OMAP_GLOBAL_WARM_RST_SRC_ID_SHIFT },
44 	{ OMAP24XX_SECU_VIOL_RST_SHIFT, OMAP_SECU_VIOL_RST_SRC_ID_SHIFT },
45 	{ OMAP24XX_MPU_WD_RST_SHIFT, OMAP_MPU_WD_RST_SRC_ID_SHIFT },
46 	{ OMAP24XX_SECU_WD_RST_SHIFT, OMAP_SECU_WD_RST_SRC_ID_SHIFT },
47 	{ OMAP24XX_EXTWMPU_RST_SHIFT, OMAP_EXTWARM_RST_SRC_ID_SHIFT },
48 	{ -1, -1 },
49 };
50 
51 /**
52  * omap2xxx_prm_read_reset_sources - return the last SoC reset source
53  *
54  * Return a u32 representing the last reset sources of the SoC.  The
55  * returned reset source bits are standardized across OMAP SoCs.
56  */
57 static u32 omap2xxx_prm_read_reset_sources(void)
58 {
59 	struct prm_reset_src_map *p;
60 	u32 r = 0;
61 	u32 v;
62 
63 	v = omap2_prm_read_mod_reg(WKUP_MOD, OMAP2_RM_RSTST);
64 
65 	p = omap2xxx_prm_reset_src_map;
66 	while (p->reg_shift >= 0 && p->std_shift >= 0) {
67 		if (v & (1 << p->reg_shift))
68 			r |= 1 << p->std_shift;
69 		p++;
70 	}
71 
72 	return r;
73 }
74 
75 /**
76  * omap2xxx_pwrst_to_common_pwrst - convert OMAP2xxx pwrst to common pwrst
77  * @omap2xxx_pwrst: OMAP2xxx hardware power state to convert
78  *
79  * Return the common power state bits corresponding to the OMAP2xxx
80  * hardware power state bits @omap2xxx_pwrst, or -EINVAL upon error.
81  */
82 static int omap2xxx_pwrst_to_common_pwrst(u8 omap2xxx_pwrst)
83 {
84 	u8 pwrst;
85 
86 	switch (omap2xxx_pwrst) {
87 	case OMAP24XX_PWRDM_POWER_OFF:
88 		pwrst = PWRDM_POWER_OFF;
89 		break;
90 	case OMAP24XX_PWRDM_POWER_RET:
91 		pwrst = PWRDM_POWER_RET;
92 		break;
93 	case OMAP24XX_PWRDM_POWER_ON:
94 		pwrst = PWRDM_POWER_ON;
95 		break;
96 	default:
97 		return -EINVAL;
98 	}
99 
100 	return pwrst;
101 }
102 
103 /**
104  * omap2xxx_prm_dpll_reset - use DPLL reset to reboot the OMAP SoC
105  *
106  * Set the DPLL reset bit, which should reboot the SoC.  This is the
107  * recommended way to restart the SoC.  No return value.
108  */
109 static void omap2xxx_prm_dpll_reset(void)
110 {
111 	omap2_prm_set_mod_reg_bits(OMAP_RST_DPLL3_MASK, WKUP_MOD,
112 				   OMAP2_RM_RSTCTRL);
113 	/* OCP barrier */
114 	omap2_prm_read_mod_reg(WKUP_MOD, OMAP2_RM_RSTCTRL);
115 }
116 
117 /**
118  * omap2xxx_prm_clear_mod_irqs - clear wakeup status bits for a module
119  * @module: PRM module to clear wakeups from
120  * @regs: register offset to clear
121  * @wkst_mask: wakeup status mask to clear
122  *
123  * Clears wakeup status bits for a given module, so that the device can
124  * re-enter idle.
125  */
126 static int omap2xxx_prm_clear_mod_irqs(s16 module, u8 regs, u32 wkst_mask)
127 {
128 	u32 wkst;
129 
130 	wkst = omap2_prm_read_mod_reg(module, regs);
131 	wkst &= wkst_mask;
132 	omap2_prm_write_mod_reg(wkst, module, regs);
133 	return 0;
134 }
135 
136 int omap2xxx_clkdm_sleep(struct clockdomain *clkdm)
137 {
138 	omap2_prm_set_mod_reg_bits(OMAP24XX_FORCESTATE_MASK,
139 				   clkdm->pwrdm.ptr->prcm_offs,
140 				   OMAP2_PM_PWSTCTRL);
141 	return 0;
142 }
143 
144 int omap2xxx_clkdm_wakeup(struct clockdomain *clkdm)
145 {
146 	omap2_prm_clear_mod_reg_bits(OMAP24XX_FORCESTATE_MASK,
147 				     clkdm->pwrdm.ptr->prcm_offs,
148 				     OMAP2_PM_PWSTCTRL);
149 	return 0;
150 }
151 
152 static int omap2xxx_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
153 {
154 	u8 omap24xx_pwrst;
155 
156 	switch (pwrst) {
157 	case PWRDM_POWER_OFF:
158 		omap24xx_pwrst = OMAP24XX_PWRDM_POWER_OFF;
159 		break;
160 	case PWRDM_POWER_RET:
161 		omap24xx_pwrst = OMAP24XX_PWRDM_POWER_RET;
162 		break;
163 	case PWRDM_POWER_ON:
164 		omap24xx_pwrst = OMAP24XX_PWRDM_POWER_ON;
165 		break;
166 	default:
167 		return -EINVAL;
168 	}
169 
170 	omap2_prm_rmw_mod_reg_bits(OMAP_POWERSTATE_MASK,
171 				   (omap24xx_pwrst << OMAP_POWERSTATE_SHIFT),
172 				   pwrdm->prcm_offs, OMAP2_PM_PWSTCTRL);
173 	return 0;
174 }
175 
176 static int omap2xxx_pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
177 {
178 	u8 omap2xxx_pwrst;
179 
180 	omap2xxx_pwrst = omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
181 						       OMAP2_PM_PWSTCTRL,
182 						       OMAP_POWERSTATE_MASK);
183 
184 	return omap2xxx_pwrst_to_common_pwrst(omap2xxx_pwrst);
185 }
186 
187 static int omap2xxx_pwrdm_read_pwrst(struct powerdomain *pwrdm)
188 {
189 	u8 omap2xxx_pwrst;
190 
191 	omap2xxx_pwrst = omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
192 						       OMAP2_PM_PWSTST,
193 						       OMAP_POWERSTATEST_MASK);
194 
195 	return omap2xxx_pwrst_to_common_pwrst(omap2xxx_pwrst);
196 }
197 
198 struct pwrdm_ops omap2_pwrdm_operations = {
199 	.pwrdm_set_next_pwrst	= omap2xxx_pwrdm_set_next_pwrst,
200 	.pwrdm_read_next_pwrst	= omap2xxx_pwrdm_read_next_pwrst,
201 	.pwrdm_read_pwrst	= omap2xxx_pwrdm_read_pwrst,
202 	.pwrdm_set_logic_retst	= omap2_pwrdm_set_logic_retst,
203 	.pwrdm_set_mem_onst	= omap2_pwrdm_set_mem_onst,
204 	.pwrdm_set_mem_retst	= omap2_pwrdm_set_mem_retst,
205 	.pwrdm_read_mem_pwrst	= omap2_pwrdm_read_mem_pwrst,
206 	.pwrdm_read_mem_retst	= omap2_pwrdm_read_mem_retst,
207 	.pwrdm_wait_transition	= omap2_pwrdm_wait_transition,
208 };
209 
210 /*
211  *
212  */
213 
214 static struct prm_ll_data omap2xxx_prm_ll_data = {
215 	.read_reset_sources = &omap2xxx_prm_read_reset_sources,
216 	.assert_hardreset = &omap2_prm_assert_hardreset,
217 	.deassert_hardreset = &omap2_prm_deassert_hardreset,
218 	.is_hardreset_asserted = &omap2_prm_is_hardreset_asserted,
219 	.reset_system = &omap2xxx_prm_dpll_reset,
220 	.clear_mod_irqs = &omap2xxx_prm_clear_mod_irqs,
221 };
222 
223 int __init omap2xxx_prm_init(const struct omap_prcm_init_data *data)
224 {
225 	return prm_register(&omap2xxx_prm_ll_data);
226 }
227 
228 static void __exit omap2xxx_prm_exit(void)
229 {
230 	prm_unregister(&omap2xxx_prm_ll_data);
231 }
232 __exitcall(omap2xxx_prm_exit);
233