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