1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * OMAP4+ Power Management Routines
4 *
5 * Copyright (C) 2010-2013 Texas Instruments, Inc.
6 * Rajendra Nayak <rnayak@ti.com>
7 * Santosh Shilimkar <santosh.shilimkar@ti.com>
8 */
9
10 #include <linux/pm.h>
11 #include <linux/suspend.h>
12 #include <linux/module.h>
13 #include <linux/list.h>
14 #include <linux/err.h>
15 #include <linux/slab.h>
16 #include <asm/system_misc.h>
17
18 #include "soc.h"
19 #include "common.h"
20 #include "clockdomain.h"
21 #include "powerdomain.h"
22 #include "pm.h"
23
24 u16 pm44xx_errata;
25
26 struct power_state {
27 struct powerdomain *pwrdm;
28 u32 next_state;
29 u32 next_logic_state;
30 #ifdef CONFIG_SUSPEND
31 u32 saved_state;
32 u32 saved_logic_state;
33 #endif
34 struct list_head node;
35 };
36
37 /**
38 * struct static_dep_map - Static dependency map
39 * @from: from clockdomain
40 * @to: to clockdomain
41 */
42 struct static_dep_map {
43 const char *from;
44 const char *to;
45 };
46
47 static u32 cpu_suspend_state = PWRDM_POWER_OFF;
48
49 static LIST_HEAD(pwrst_list);
50
51 #ifdef CONFIG_SUSPEND
52 static int omap4_pm_suspend(void)
53 {
54 struct power_state *pwrst;
55 int state, ret = 0;
56 u32 cpu_id = smp_processor_id();
57
58 /* Save current powerdomain state */
59 list_for_each_entry(pwrst, &pwrst_list, node) {
60 pwrst->saved_state = pwrdm_read_next_pwrst(pwrst->pwrdm);
61 pwrst->saved_logic_state = pwrdm_read_logic_retst(pwrst->pwrdm);
62 }
63
64 /* Set targeted power domain states by suspend */
65 list_for_each_entry(pwrst, &pwrst_list, node) {
66 omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
67 pwrdm_set_logic_retst(pwrst->pwrdm, pwrst->next_logic_state);
68 }
69
70 /*
71 * For MPUSS to hit power domain retention(CSWR or OSWR),
72 * CPU0 and CPU1 power domains need to be in OFF or DORMANT state,
73 * since CPU power domain CSWR is not supported by hardware
74 * Only master CPU follows suspend path. All other CPUs follow
75 * CPU hotplug path in system wide suspend. On OMAP4, CPU power
76 * domain CSWR is not supported by hardware.
77 * More details can be found in OMAP4430 TRM section 4.3.4.2.
78 */
79 omap4_enter_lowpower(cpu_id, cpu_suspend_state, false);
80
81 /* Restore next powerdomain state */
82 list_for_each_entry(pwrst, &pwrst_list, node) {
83 state = pwrdm_read_prev_pwrst(pwrst->pwrdm);
84 if (state > pwrst->next_state) {
85 pr_info("Powerdomain (%s) didn't enter target state %d\n",
86 pwrst->pwrdm->name, pwrst->next_state);
87 ret = -1;
88 }
89 omap_set_pwrdm_state(pwrst->pwrdm, pwrst->saved_state);
90 pwrdm_set_logic_retst(pwrst->pwrdm, pwrst->saved_logic_state);
91 }
92 if (ret) {
93 pr_crit("Could not enter target state in pm_suspend\n");
94 /*
95 * OMAP4 chip PM currently works only with certain (newer)
96 * versions of bootloaders. This is due to missing code in the
97 * kernel to properly reset and initialize some devices.
98 * Warn the user about the bootloader version being one of the
99 * possible causes.
100 * http://www.spinics.net/lists/arm-kernel/msg218641.html
101 */
102 pr_debug("A possible cause could be an old bootloader - try u-boot >= v2012.07\n");
103 } else {
104 pr_info("Successfully put all powerdomains to target state\n");
105 }
106
107 return 0;
108 }
109 #else
110 #define omap4_pm_suspend NULL
111 #endif /* CONFIG_SUSPEND */
112
113 static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused)
114 {
115 struct power_state *pwrst;
116
117 if (!pwrdm->pwrsts)
118 return 0;
119
120 /*
121 * Skip CPU0 and CPU1 power domains. CPU1 is programmed
122 * through hotplug path and CPU0 explicitly programmed
123 * further down in the code path
124 */
125 if (!strncmp(pwrdm->name, "cpu", 3)) {
126 if (IS_PM44XX_ERRATUM(PM_OMAP4_CPU_OSWR_DISABLE))
127 cpu_suspend_state = PWRDM_POWER_RET;
128 return 0;
129 }
130
131 if (!strncmp(pwrdm->name, "core", 4) ||
132 !strncmp(pwrdm->name, "l4per", 5))
133 pwrdm_set_logic_retst(pwrdm, PWRDM_POWER_OFF);
134
135 pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC);
136 if (!pwrst)
137 return -ENOMEM;
138
139 pwrst->pwrdm = pwrdm;
140 pwrst->next_state = pwrdm_get_valid_lp_state(pwrdm, false,
141 PWRDM_POWER_RET);
142 pwrst->next_logic_state = pwrdm_get_valid_lp_state(pwrdm, true,
143 PWRDM_POWER_OFF);
144
145 list_add(&pwrst->node, &pwrst_list);
146
147 return omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
148 }
149
150 /**
151 * omap_default_idle - OMAP4 default ilde routine.'
152 *
153 * Implements OMAP4 memory, IO ordering requirements which can't be addressed
154 * with default cpu_do_idle() hook. Used by all CPUs with !CONFIG_CPU_IDLE and
155 * by secondary CPU with CONFIG_CPU_IDLE.
156 */
157 static void omap_default_idle(void)
158 {
159 omap_do_wfi();
160 }
161
162 /*
163 * The dynamic dependency between MPUSS -> MEMIF and
164 * MPUSS -> L4_PER/L3_* and DUCATI -> L3_* doesn't work as
165 * expected. The hardware recommendation is to enable static
166 * dependencies for these to avoid system lock ups or random crashes.
167 * The L4 wakeup depedency is added to workaround the OCP sync hardware
168 * BUG with 32K synctimer which lead to incorrect timer value read
169 * from the 32K counter. The BUG applies for GPTIMER1 and WDT2 which
170 * are part of L4 wakeup clockdomain.
171 */
172 static const struct static_dep_map omap4_static_dep_map[] = {
173 {.from = "mpuss_clkdm", .to = "l3_emif_clkdm"},
174 {.from = "mpuss_clkdm", .to = "l3_1_clkdm"},
175 {.from = "mpuss_clkdm", .to = "l3_2_clkdm"},
176 {.from = "ducati_clkdm", .to = "l3_1_clkdm"},
177 {.from = "ducati_clkdm", .to = "l3_2_clkdm"},
178 {.from = NULL} /* TERMINATION */
179 };
180
181 static const struct static_dep_map omap5_dra7_static_dep_map[] = {
182 {.from = "mpu_clkdm", .to = "emif_clkdm"},
183 {.from = NULL} /* TERMINATION */
184 };
185
186 /**
187 * omap4plus_init_static_deps() - Initialize a static dependency map
188 * @map: Mapping of clock domains
189 */
190 static inline int omap4plus_init_static_deps(const struct static_dep_map *map)
191 {
192 int ret;
193 struct clockdomain *from, *to;
194
195 if (!map)
196 return 0;
197
198 while (map->from) {
199 from = clkdm_lookup(map->from);
200 to = clkdm_lookup(map->to);
201 if (!from || !to) {
202 pr_err("Failed lookup %s or %s for wakeup dependency\n",
203 map->from, map->to);
204 return -EINVAL;
205 }
206 ret = clkdm_add_wkdep(from, to);
207 if (ret) {
208 pr_err("Failed to add %s -> %s wakeup dependency(%d)\n",
209 map->from, map->to, ret);
210 return ret;
211 }
212
213 map++;
214 }
215
216 return 0;
217 }
218
219 /**
220 * omap4_pm_init_early - Does early initialization necessary for OMAP4+ devices
221 *
222 * Initializes basic stuff for power management functionality.
223 */
224 int __init omap4_pm_init_early(void)
225 {
226 if (cpu_is_omap446x())
227 pm44xx_errata |= PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD;
228
229 if (soc_is_omap54xx() || soc_is_dra7xx())
230 pm44xx_errata |= PM_OMAP4_CPU_OSWR_DISABLE;
231
232 return 0;
233 }
234
235 /**
236 * omap4_pm_init - Init routine for OMAP4+ devices
237 *
238 * Initializes all powerdomain and clockdomain target states
239 * and all PRCM settings.
240 * Return: Returns the error code returned by called functions.
241 */
242 int __init omap4_pm_init(void)
243 {
244 int ret = 0;
245
246 if (omap_rev() == OMAP4430_REV_ES1_0) {
247 WARN(1, "Power Management not supported on OMAP4430 ES1.0\n");
248 return -ENODEV;
249 }
250
251 pr_info("Power Management for TI OMAP4+ devices.\n");
252
253 /*
254 * OMAP4 chip PM currently works only with certain (newer)
255 * versions of bootloaders. This is due to missing code in the
256 * kernel to properly reset and initialize some devices.
257 * http://www.spinics.net/lists/arm-kernel/msg218641.html
258 */
259 if (cpu_is_omap44xx())
260 pr_debug("OMAP4 PM: u-boot >= v2012.07 is required for full PM support\n");
261
262 ret = pwrdm_for_each(pwrdms_setup, NULL);
263 if (ret) {
264 pr_err("Failed to setup powerdomains.\n");
265 goto err2;
266 }
267
268 if (cpu_is_omap44xx())
269 ret = omap4plus_init_static_deps(omap4_static_dep_map);
270 else if (soc_is_omap54xx() || soc_is_dra7xx())
271 ret = omap4plus_init_static_deps(omap5_dra7_static_dep_map);
272
273 if (ret) {
274 pr_err("Failed to initialise static dependencies.\n");
275 goto err2;
276 }
277
278 ret = omap4_mpuss_init();
279 if (ret) {
280 pr_err("Failed to initialise OMAP4 MPUSS\n");
281 goto err2;
282 }
283
284 (void) clkdm_for_each(omap_pm_clkdms_setup, NULL);
285
286 omap_common_suspend_init(omap4_pm_suspend);
287
288 /* Overwrite the default cpu_do_idle() */
289 arm_pm_idle = omap_default_idle;
290
291 if (cpu_is_omap44xx() || soc_is_omap54xx())
292 omap4_idle_init();
293
294 err2:
295 return ret;
296 }
297
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