xref: /openbmc/linux/arch/arm/mach-omap2/prm2xxx.c (revision 55fd7e02)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * OMAP2xxx PRM module functions
4  *
5  * Copyright (C) 2010-2012 Texas Instruments, Inc.
6  * Copyright (C) 2010 Nokia Corporation
7  * Benoît Cousson
8  * Paul Walmsley
9  * Rajendra Nayak <rnayak@ti.com>
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/errno.h>
14 #include <linux/err.h>
15 #include <linux/io.h>
16 #include <linux/irq.h>
17 
18 #include "powerdomain.h"
19 #include "clockdomain.h"
20 #include "prm2xxx.h"
21 #include "cm2xxx_3xxx.h"
22 #include "prm-regbits-24xx.h"
23 
24 /*
25  * OMAP24xx PM_PWSTCTRL_*.POWERSTATE and PM_PWSTST_*.LASTSTATEENTERED bits -
26  * these are reversed from the bits used on OMAP3+
27  */
28 #define OMAP24XX_PWRDM_POWER_ON			0x0
29 #define OMAP24XX_PWRDM_POWER_RET		0x1
30 #define OMAP24XX_PWRDM_POWER_OFF		0x3
31 
32 /*
33  * omap2xxx_prm_reset_src_map - map from bits in the PRM_RSTST_WKUP
34  *   hardware register (which are specific to the OMAP2xxx SoCs) to
35  *   reset source ID bit shifts (which is an OMAP SoC-independent
36  *   enumeration)
37  */
38 static struct prm_reset_src_map omap2xxx_prm_reset_src_map[] = {
39 	{ OMAP_GLOBALCOLD_RST_SHIFT, OMAP_GLOBAL_COLD_RST_SRC_ID_SHIFT },
40 	{ OMAP_GLOBALWARM_RST_SHIFT, OMAP_GLOBAL_WARM_RST_SRC_ID_SHIFT },
41 	{ OMAP24XX_SECU_VIOL_RST_SHIFT, OMAP_SECU_VIOL_RST_SRC_ID_SHIFT },
42 	{ OMAP24XX_MPU_WD_RST_SHIFT, OMAP_MPU_WD_RST_SRC_ID_SHIFT },
43 	{ OMAP24XX_SECU_WD_RST_SHIFT, OMAP_SECU_WD_RST_SRC_ID_SHIFT },
44 	{ OMAP24XX_EXTWMPU_RST_SHIFT, OMAP_EXTWARM_RST_SRC_ID_SHIFT },
45 	{ -1, -1 },
46 };
47 
48 /**
49  * omap2xxx_prm_read_reset_sources - return the last SoC reset source
50  *
51  * Return a u32 representing the last reset sources of the SoC.  The
52  * returned reset source bits are standardized across OMAP SoCs.
53  */
54 static u32 omap2xxx_prm_read_reset_sources(void)
55 {
56 	struct prm_reset_src_map *p;
57 	u32 r = 0;
58 	u32 v;
59 
60 	v = omap2_prm_read_mod_reg(WKUP_MOD, OMAP2_RM_RSTST);
61 
62 	p = omap2xxx_prm_reset_src_map;
63 	while (p->reg_shift >= 0 && p->std_shift >= 0) {
64 		if (v & (1 << p->reg_shift))
65 			r |= 1 << p->std_shift;
66 		p++;
67 	}
68 
69 	return r;
70 }
71 
72 /**
73  * omap2xxx_pwrst_to_common_pwrst - convert OMAP2xxx pwrst to common pwrst
74  * @omap2xxx_pwrst: OMAP2xxx hardware power state to convert
75  *
76  * Return the common power state bits corresponding to the OMAP2xxx
77  * hardware power state bits @omap2xxx_pwrst, or -EINVAL upon error.
78  */
79 static int omap2xxx_pwrst_to_common_pwrst(u8 omap2xxx_pwrst)
80 {
81 	u8 pwrst;
82 
83 	switch (omap2xxx_pwrst) {
84 	case OMAP24XX_PWRDM_POWER_OFF:
85 		pwrst = PWRDM_POWER_OFF;
86 		break;
87 	case OMAP24XX_PWRDM_POWER_RET:
88 		pwrst = PWRDM_POWER_RET;
89 		break;
90 	case OMAP24XX_PWRDM_POWER_ON:
91 		pwrst = PWRDM_POWER_ON;
92 		break;
93 	default:
94 		return -EINVAL;
95 	}
96 
97 	return pwrst;
98 }
99 
100 /**
101  * omap2xxx_prm_dpll_reset - use DPLL reset to reboot the OMAP SoC
102  *
103  * Set the DPLL reset bit, which should reboot the SoC.  This is the
104  * recommended way to restart the SoC.  No return value.
105  */
106 static void omap2xxx_prm_dpll_reset(void)
107 {
108 	omap2_prm_set_mod_reg_bits(OMAP_RST_DPLL3_MASK, WKUP_MOD,
109 				   OMAP2_RM_RSTCTRL);
110 	/* OCP barrier */
111 	omap2_prm_read_mod_reg(WKUP_MOD, OMAP2_RM_RSTCTRL);
112 }
113 
114 /**
115  * omap2xxx_prm_clear_mod_irqs - clear wakeup status bits for a module
116  * @module: PRM module to clear wakeups from
117  * @regs: register offset to clear
118  * @wkst_mask: wakeup status mask to clear
119  *
120  * Clears wakeup status bits for a given module, so that the device can
121  * re-enter idle.
122  */
123 static int omap2xxx_prm_clear_mod_irqs(s16 module, u8 regs, u32 wkst_mask)
124 {
125 	u32 wkst;
126 
127 	wkst = omap2_prm_read_mod_reg(module, regs);
128 	wkst &= wkst_mask;
129 	omap2_prm_write_mod_reg(wkst, module, regs);
130 	return 0;
131 }
132 
133 int omap2xxx_clkdm_sleep(struct clockdomain *clkdm)
134 {
135 	omap2_prm_set_mod_reg_bits(OMAP24XX_FORCESTATE_MASK,
136 				   clkdm->pwrdm.ptr->prcm_offs,
137 				   OMAP2_PM_PWSTCTRL);
138 	return 0;
139 }
140 
141 int omap2xxx_clkdm_wakeup(struct clockdomain *clkdm)
142 {
143 	omap2_prm_clear_mod_reg_bits(OMAP24XX_FORCESTATE_MASK,
144 				     clkdm->pwrdm.ptr->prcm_offs,
145 				     OMAP2_PM_PWSTCTRL);
146 	return 0;
147 }
148 
149 static int omap2xxx_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
150 {
151 	u8 omap24xx_pwrst;
152 
153 	switch (pwrst) {
154 	case PWRDM_POWER_OFF:
155 		omap24xx_pwrst = OMAP24XX_PWRDM_POWER_OFF;
156 		break;
157 	case PWRDM_POWER_RET:
158 		omap24xx_pwrst = OMAP24XX_PWRDM_POWER_RET;
159 		break;
160 	case PWRDM_POWER_ON:
161 		omap24xx_pwrst = OMAP24XX_PWRDM_POWER_ON;
162 		break;
163 	default:
164 		return -EINVAL;
165 	}
166 
167 	omap2_prm_rmw_mod_reg_bits(OMAP_POWERSTATE_MASK,
168 				   (omap24xx_pwrst << OMAP_POWERSTATE_SHIFT),
169 				   pwrdm->prcm_offs, OMAP2_PM_PWSTCTRL);
170 	return 0;
171 }
172 
173 static int omap2xxx_pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
174 {
175 	u8 omap2xxx_pwrst;
176 
177 	omap2xxx_pwrst = omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
178 						       OMAP2_PM_PWSTCTRL,
179 						       OMAP_POWERSTATE_MASK);
180 
181 	return omap2xxx_pwrst_to_common_pwrst(omap2xxx_pwrst);
182 }
183 
184 static int omap2xxx_pwrdm_read_pwrst(struct powerdomain *pwrdm)
185 {
186 	u8 omap2xxx_pwrst;
187 
188 	omap2xxx_pwrst = omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
189 						       OMAP2_PM_PWSTST,
190 						       OMAP_POWERSTATEST_MASK);
191 
192 	return omap2xxx_pwrst_to_common_pwrst(omap2xxx_pwrst);
193 }
194 
195 struct pwrdm_ops omap2_pwrdm_operations = {
196 	.pwrdm_set_next_pwrst	= omap2xxx_pwrdm_set_next_pwrst,
197 	.pwrdm_read_next_pwrst	= omap2xxx_pwrdm_read_next_pwrst,
198 	.pwrdm_read_pwrst	= omap2xxx_pwrdm_read_pwrst,
199 	.pwrdm_set_logic_retst	= omap2_pwrdm_set_logic_retst,
200 	.pwrdm_set_mem_onst	= omap2_pwrdm_set_mem_onst,
201 	.pwrdm_set_mem_retst	= omap2_pwrdm_set_mem_retst,
202 	.pwrdm_read_mem_pwrst	= omap2_pwrdm_read_mem_pwrst,
203 	.pwrdm_read_mem_retst	= omap2_pwrdm_read_mem_retst,
204 	.pwrdm_wait_transition	= omap2_pwrdm_wait_transition,
205 };
206 
207 /*
208  *
209  */
210 
211 static struct prm_ll_data omap2xxx_prm_ll_data = {
212 	.read_reset_sources = &omap2xxx_prm_read_reset_sources,
213 	.assert_hardreset = &omap2_prm_assert_hardreset,
214 	.deassert_hardreset = &omap2_prm_deassert_hardreset,
215 	.is_hardreset_asserted = &omap2_prm_is_hardreset_asserted,
216 	.reset_system = &omap2xxx_prm_dpll_reset,
217 	.clear_mod_irqs = &omap2xxx_prm_clear_mod_irqs,
218 };
219 
220 int __init omap2xxx_prm_init(const struct omap_prcm_init_data *data)
221 {
222 	return prm_register(&omap2xxx_prm_ll_data);
223 }
224 
225 static void __exit omap2xxx_prm_exit(void)
226 {
227 	prm_unregister(&omap2xxx_prm_ll_data);
228 }
229 __exitcall(omap2xxx_prm_exit);
230